58 results on '"Egidio Brocca-Cofano"'
Search Results
2. T cell activation is insufficient to drive SIV disease progression
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Cristian Apetrei, Thaidra Gaufin, Egidio Brocca-Cofano, Ranjit Sivanandham, Paola Sette, Tianyu He, Sindhuja Sivanandham, Natalie Martinez Sosa, Kathryn J. Martin, Kevin D. Raehtz, Adam J. Kleinman, Audrey Valentine, Noah Krampe, Rajeev Gautam, Andrew A. Lackner, Alan L. Landay, Ruy M. Ribeiro, and Ivona Pandrea
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AIDS/HIV ,Infectious disease ,Medicine - Abstract
Resolution of T cell activation and inflammation is a key determinant of the lack of SIV disease progression in African green monkeys (AGMs). Although frequently considered together, T cell activation occurs in response to viral stimulation of acquired immunity, while inflammation reflects innate immune responses to mucosal injury. We dissociated T cell activation from inflammation through regulatory T cell (Treg) depletion with Ontak (interleukin-2 coupled with diphtheria toxin) during early SIV infection of AGMs. This intervention abolished control of T cell immune activation beyond the transition from acute to chronic infection. Ontak had no effect on gut barrier integrity, microbial translocation, inflammation, and hypercoagulation, despite increasing T cell activation. Ontak administration increased macrophage counts yet decreased their activation. Persistent T cell activation influenced SIV pathogenesis, shifting the ramp-up in viral replication to earlier time points, prolonging the high levels of replication, and delaying CD4+ T cell restoration yet without any clinical or biological sign of disease progression in Treg-depleted AGMs. Thus, by inducing T cell activation without damaging mucosal barrier integrity, we showed that systemic T cell activation per se is not sufficient to drive disease progression, which suggests that control of systemic inflammation (likely through maintenance of gut integrity) is the key determinant of lack of disease progression in natural hosts of SIVs.
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- 2023
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3. Pharmacokinetics and Immunological Effects of Romidepsin in Rhesus Macaques
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Adam J. Kleinman, Cuiling Xu, Mackenzie L. Cottrell, Ranjit Sivanandham, Egidio Brocca-Cofano, Tammy Dunsmore, Angela Kashuba, Ivona Pandrea, and Cristian Apetrei
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romidepsin ,histone deacetylase inhibitors ,latency reversing agents ,human immunodeficiency virus ,simian immunodeficiency virus ,HIV latency ,Immunologic diseases. Allergy ,RC581-607 - Abstract
HIV/SIV persistence in latent reservoirs requires lifelong antiretroviral treatment and calls for effective cure strategies. Romidepsin (RMD), a histone deacetylase inhibitor, was reported to reactivate HIV/SIV from reservoirs in virus-suppressed individuals. We characterized in detail the pharmacokinetics and safety profile of RMD in three SIV-naïve rhesus macaques which received two rounds of treatment. In plasma, RMD mean terminal half-life was 15.3 h. In comparison, RMD mean terminal half-life was much longer in tissues: 110 h in the lymph nodes (LNs) and 28 h in gastrointestinal tract. RMD administration was accompanied by transient liver and systemic toxicity. Isoflurane anesthesia induced near-immediate transient lymphopenia, which was further exacerbated and extended with the extensive immune modifications by RMD. The effect of RMD on circulating immune cells was complex: (i) slight increase in lymphocyte death rates; (ii) transient, robust increase in neutrophils; (iii) massive downregulation of lymphocyte surface markers; (iv) important migration of CD3+ T cells to the gut and LNs; and (v) hindrance to CD8+ T cell functionality, yet without reaching significance. Our results show that, in contrast to transient plasma concentrations, RMD has a long-term presence in tissues, with multiple immunomodulatory effects and minimal to moderate kidney, liver, and lymphocyte toxicities. As such, we concluded that RMD can be used for “shock and kill” approaches, preferentially in combination with other latency reversal agents or cytotoxic T lymphocyte boosting strategies with consideration taken for adverse effects.
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- 2020
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4. Kaposi’s Sarcoma Lesion Progression in BKV-Tat Transgenic Mice Is Increased by Inflammatory Cytokines and Blocked by Treatment with Anti-Tat Antibodies
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Egidio Brocca-Cofano, Cecilia Sgadari, Orietta Picconi, Clelia Palladino, Antonella Caputo, and Barbara Ensoli
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HIV-1 tat ,BKV/Tat transgenic mice ,KS-like lesions ,inflammatory cytokines ,anti-Tat antibodies ,KS regression ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Kaposi’s sarcoma (KS) is an angioproliferative tumor showing an increased frequency and aggressiveness in HIV-infected subjects (AIDS-KS), due to the combined effects of inflammatory cytokines (IC), angiogenic factors, and the HIV-1 Tat protein. While the introduction of effective combined antiretroviral regimens greatly improved AIDS-KS incidence and course, it continues to be an incurable disease and the development of new rational targeted therapies is warranted. We used the BKV/Tat transgenic mouse model to evaluate the effects of IC and anti-Tat antibodies (Abs) treatment on KS-like lesions arising in BKV/Tat mice. We demonstrated here that IC-treatment increases the severity and delays the regression of KS-like lesions. Further, anti-Tat Abs reduced KS-like lesion severity developing in IC-treated mice when anti-Tat Abs were administered at an early-stage of lesion development as compared to more advanced lesions. Early anti-Tat Abs treatment also accelerated KS-like lesion regression and reduced the rate of severe-grade lesions. This effect was more evident in the first weeks after Ab treatment, suggesting that a longer treatment with anti-Tat Abs might be even more effective, particularly if administered just after lesion development. Although preliminary, these results are encouraging, and the approach deserves further studies for the development of anti-Tat Ab-based therapies for AIDS-KS. Clinical studies specifically addressing the effect of anti-Tat antibodies in treating AIDS-KS are not yet available. Nevertheless, the effectiveness of anti-Tat antibodies in controlling HIV/AIDS progression, likely due to the neutralization of extracellular Tat activities, is suggested by several cross-sectional and longitudinal clinical studies, indicating that anti-Tat Ab treatment or Tat-based vaccines may be effective to treat AIDS-KS patients or prevent the tumor in individuals at risk.
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- 2022
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5. African green monkeys avoid SIV disease progression by preventing intestinal dysfunction and maintaining mucosal barrier integrity.
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Kevin D Raehtz, Fredrik Barrenäs, Cuiling Xu, Kathleen Busman-Sahay, Audrey Valentine, Lynn Law, Dongzhu Ma, Benjamin B Policicchio, Viskam Wijewardana, Egidio Brocca-Cofano, Anita Trichel, Michael Gale, Brandon F Keele, Jacob D Estes, Cristian Apetrei, and Ivona Pandrea
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Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
Unlike HIV infection, SIV infection is generally nonpathogenic in natural hosts, such as African green monkeys (AGMs), despite life-long high viral replication. Lack of disease progression was reportedly based on the ability of SIV-infected AGMs to prevent gut dysfunction, avoiding microbial translocation and the associated systemic immune activation and chronic inflammation. Yet, the maintenance of gut integrity has never been documented, and the mechanism(s) by which gut integrity is preserved are unknown. We sought to investigate the early events of SIV infection in AGMs, specifically examining the impact of SIVsab infection on the gut mucosa. Twenty-nine adult male AGMs were intrarectally infected with SIVsab92018 and serially sacrificed at well-defined stages of SIV infection, preramp-up (1-3 days post-infection (dpi)), ramp-up (4-6 dpi), peak viremia (9-12 dpi), and early chronic SIV infection (46-55 dpi), to assess the levels of immune activation, apoptosis, epithelial damage and microbial translocation in the GI tract and peripheral lymph nodes. Tissue viral loads, plasma cytokines and plasma markers of gut dysfunction were also measured throughout the course of early infection. While a strong, but transient, interferon-based inflammatory response was observed, the levels of plasma markers linked to enteropathy did not increase. Accordingly, no significant increases in apoptosis of either mucosal enterocytes or lymphocytes, and no damage to the mucosal epithelium were documented during early SIVsab infection of AGMs. These findings were supported by RNAseq of the gut tissue, which found no significant alterations in gene expression that would indicate microbial translocation. Thus, for the first time, we confirmed that gut epithelial integrity is preserved, with no evidence of microbial translocation, in AGMs throughout early SIVsab infection. This might protect AGMs from developing intestinal dysfunction and the subsequent chronic inflammation that drives both HIV disease progression and HIV-associated comorbidities.
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- 2020
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6. Increased excitability in tat-transgenic mice: Role of tat in HIV-related neurological disorders
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Silvia Zucchini, Anna Pittaluga, Egidio Brocca-Cofano, Maria Summa, Marina Fabris, Rita De Michele, Angela Bonaccorsi, Graziella Busatto, Giuseppe Barbanti-Brodano, Giuseppe Altavilla, Gianluca Verlengia, Pierangelo Cifelli, Alfredo Corallini, Antonella Caputo, and Michele Simonato
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HIV-1-tat-transgenic mice ,HIV-1 associated neurocognitive disorders ,Seizures ,Kainate ,Neurodegeneration ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
HIV-1 associated neurocognitive disorders (HAND) are a major complication of HIV-1 infection. The mechanism(s) underlying HAND are not completely understood but, based on in vitro studies, the HIV-1 Tat protein may play an important role. In this study, the effect of prolonged exposure to endogenously produced Tat in the brain was investigated using a tat-transgenic (TT) mouse model constitutively expressing the HIV-1 tat gene. We found that stimulus-evoked glutamate exocytosis in the hippocampus and cortex was significantly increased in TT as compared with wild-type control (CC) mice, while GABA exocytosis was unchanged in the hippocampus and decreased in the cortex. This suggests that Tat generates a latent hyper-excitability state, which favors the detrimental effects of neurotoxic and/or excitotoxic agents. To challenge this idea, TT mice were tested for susceptibility to kainate-induced seizures and neurodegeneration, and found to exhibit significantly greater responses to the convulsant agent than CC mice. These results support the concept that constitutive expression of tat in the brain generates a latent excitatory state, which may increase the negative effects of damaging insults. These events may play a key role in the development of HAND.
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- 2013
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7. Multi-dose Romidepsin Reactivates Replication Competent SIV in Post-antiretroviral Rhesus Macaque Controllers.
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Benjamin B Policicchio, Cuiling Xu, Egidio Brocca-Cofano, Kevin D Raehtz, Tianyu He, Dongzhu Ma, Hui Li, Ranjit Sivanandham, George S Haret-Richter, Tammy Dunsmore, Anita Trichel, John W Mellors, Beatrice H Hahn, George M Shaw, Ruy M Ribeiro, Ivona Pandrea, and Cristian Apetrei
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Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
Viruses that persist despite seemingly effective antiretroviral treatment (ART) and can reinitiate infection if treatment is stopped preclude definitive treatment of HIV-1 infected individuals, requiring lifelong ART. Among strategies proposed for targeting these viral reservoirs, the premise of the "shock and kill" strategy is to induce expression of latent proviruses [for example with histone deacetylase inhibitors (HDACis)] resulting in elimination of the affected cells through viral cytolysis or immune clearance mechanisms. Yet, ex vivo studies reported that HDACis have variable efficacy for reactivating latent proviruses, and hinder immune functions. We developed a nonhuman primate model of post-treatment control of SIV through early and prolonged administration of ART and performed in vivo reactivation experiments in controller RMs, evaluating the ability of the HDACi romidepsin (RMD) to reactivate SIV and the impact of RMD treatment on SIV-specific T cell responses. Ten RMs were IV-infected with a SIVsmmFTq transmitted-founder infectious molecular clone. Four RMs received conventional ART for >9 months, starting from 65 days post-infection. SIVsmmFTq plasma viremia was robustly controlled to
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- 2016
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8. Lack of Specific Regulatory T Cell Depletion and Cytoreduction Associated with Extensive Toxicity After Administration of Low and High Doses of Cyclophosphamide
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Cristian Apetrei, Adam J. Kleinman, Brandon F. Keele, Ivona Pandrea, Egidio Brocca-Cofano, Colin McAndrews, Ranjit Sivanandham, and Paola Sette
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CD4-Positive T-Lymphocytes ,0301 basic medicine ,Cyclophosphamide ,Regulatory T cell ,viruses ,Immunology ,Population ,Simian Acquired Immunodeficiency Syndrome ,Human immunodeficiency virus (HIV) ,HIV Infections ,Pathogenesis ,Virus Replication ,medicine.disease_cause ,T-Lymphocytes, Regulatory ,Treg depletion ,03 medical and health sciences ,0302 clinical medicine ,Virology ,medicine ,High doses ,Animals ,Humans ,030212 general & internal medicine ,education ,education.field_of_study ,business.industry ,Cytoreduction Surgical Procedures ,Viral Load ,Simian immunodeficiency virus ,Macaca mulatta ,030104 developmental biology ,Infectious Diseases ,medicine.anatomical_structure ,Anti-Retroviral Agents ,Toxicity ,Simian Immunodeficiency Virus ,business ,medicine.drug - Abstract
Up to 93% of the human immunodeficiency virus (HIV) latent reservoir comprised defective proviruses, suggesting that a functional cure is possible through the elimination of a small population of cells containing intact virus, instead of the entire reservoir. Cyclophosphamide (Cy) is an established chemotherapeutic agent for immune cell cancers. In high doses, Cy is a nonselective cytoreductor, used in allogeneic stem-cell transplantation, while in a low dose, metronomic schedule, Cy selectively depletes regulatory T cells (Tregs). We administered low and high doses to simian immunodeficiency virus (SIV)-infected rhesus macaques (RM) to assess their effects on the SIV reservoirs. As a Treg-depleting agent, Cy unselectively depleted Treg and total lymphocytes, resulting in minimal immune activation and no viral reactivation. As a cytoreductive agent, Cy induced massive viral reactivation in elite controller RMs without ART. However, when administered with antiretroviral therapy (ART), Cy had substantial adverse effects, including mortality. Our study thus dissuades further investigation of Cy as an HIV cure agent.
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- 2022
9. A Phase 1/1b Multicenter Ascending Dose Study to Evaluate the Safety of HA-1 Minor Histocompatibility Antigen-Reactive TCR-Modified T Cells (BSB-1001) in Patients Undergoing HLA-Matched Allogenic Hematopoietic Stem Cell Transplant (alloSCT) for MRD+ AML or ALL or Poor/Very Poor Risk MDS
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Sawa Ito, Christine Voigt, Tim Mayall, Mark J Shlomchik, Jennifer D Roy, Egidio Brocca Cofano, Stephanie Stras, David Apelian, Robert Keefe, and Warren D Shlomchik
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Transplantation ,Immunology ,Molecular Medicine ,Immunology and Allergy ,Cell Biology ,Hematology ,Biochemistry - Published
- 2022
10. Changes to the Simian Immunodeficiency Virus (SIV) Reservoir and Enhanced SIV-Specific Responses in a Rhesus Macaque Model of Functional Cure after Serial Rounds of Romidepsin Administrations
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Adam J. Kleinman, Sindhuja Sivanandham, Paola Sette, Ranjit Sivanandham, Benjamin B. Policicchio, Cuiling Xu, Ellen Penn, Egidio Brocca-Cofano, Quentin Le Hingrat, Dongzhu Ma, Ivona Pandrea, and Cristian Apetrei
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CD4-Positive T-Lymphocytes ,Immunology ,Simian Acquired Immunodeficiency Syndrome ,HIV Infections ,CD8-Positive T-Lymphocytes ,Viral Load ,Virus Replication ,Microbiology ,Macaca mulatta ,Anti-Retroviral Agents ,Virology ,Insect Science ,Depsipeptides ,Leukocytes, Mononuclear ,Animals ,Pathogenesis and Immunity ,Simian Immunodeficiency Virus ,Virus Activation - Abstract
HIV persistence requires lifelong antiretroviral therapy (ART), calling for a cure. The histone deacetylase inhibitor, romidepsin, is used in the “shock and kill” approach with the goal of reactivating virus and subsequently clearing infected cells through cell-mediated immune responses. We tested serial and double infusions of romidepsin in a rhesus macaque (RM) model of SIV functional cure, which controls virus without ART. Off ART, romidepsin reactivated SIV in all RMs. Subsequent infusions resulted in diminished reactivation, and two RMs did not reactivate the virus after the second or third infusions. Therefore, those two RMs received CD8-depleting antibody to assess the replication competence of the residual reservoir. The remaining RMs received double infusions, i.e., two doses separated by 48-h. Double infusions were well tolerated, induced immune activation, and effectively reactivated SIV. Although reactivation was gradually diminished, cell-associated viral DNA was minimally changed, and viral outgrowth occurred in 4/5 RMs. In the RM which did not reactivate after CD8 depletion, viral outgrowth was not detected in peripheral blood mononuclear cells (PBMC)-derived CD4(+) cells. The frequency of SIV-specific CD8(+) T cells increased after romidepsin administration, and the increased SIV-specific immune responses were associated, although not statistically, with the diminished reactivation. Thus, our data showing sequential decreases in viral reactivation with repeated romidepsin administrations with all RMs and absence of viral reactivation after CD8(+) T-cell depletion in one animal suggest that, in the context of healthy immune responses, romidepsin affected the inducible viral reservoir and gradually increased immune-mediated viral control. Given the disparities between the results of romidepsin administration to ART-suppressed SIVmac239-infected RMs and HIV-infected normal progressors compared to our immune-healthy model, our data suggest that improving immune function for greater SIV-specific responses should be the starting point of HIV cure strategies. IMPORTANCE HIV cure is sought after due to the prevalence of comorbidities that occur in persons with HIV. One of the most investigated HIV cure strategies is the “shock and kill” approach. Our study investigated the use of romidepsin, a histone deacetylase (HDAC) inhibitor, in our rhesus macaque model of functional cure, which allows for better resolution of viral reactivation due to the lack of antiretroviral therapy. We found that repeated rounds of romidepsin resulted in gradually diminished viral reactivation. One animal inevitably lacked replication-competent virus in the blood. With the accompanying enhancement of the SIV-specific immune response, our data suggest that there is a reduction of the viral reservoir in one animal by the cell-mediated immune response. With the differences observed between our model and persons living with HIV (PWH) treated with romidepsin, specifically in the context of a healthy immune system in our model, our data thereby indicate the importance of restoring the immune system for cure strategies.
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- 2022
11. Abstract 5189: High throughput single-cell based cloning reveals functional diversity of T cell receptors targeting minor histocompatibility antigen
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Sawa Ito, Constantinos G. Panousis, Alexander M. Rowe, Kedwin Ventura, Jennifer D. Roy, Stephanie Stras, Egidio Brocca-Cofano, Josh Kim, Mark J. Shlomchik, and Warren D. Shlomchik
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Cancer Research ,Oncology - Abstract
Hematopoietically-restricted minor histocompatibility antigens (miHAs) specific T cells can mediate graft-versus-leukemia and promote engraftment with a low risk of graft-vs-host disease in allogeneic stem cell transplantation (alloSCT). Thus the miHA are ideal targets for adoptive T cell immunotherapy for the recipient of alloSCT. We developed a novel single-cell based high-throughput technology (TCXpress) for cloning T cell receptors (TCRs) and successfully cloned multiple TCRs reactive against the miHA, HA-1 from a parous woman who was naturally immunized to HA-1 through pregnancy. We identified an HLA-A*02:01 woman homozygous for the non-immunogenic HA-1 alleles (R/R) who had pregnancies from an HA-1(H/R) father. TCRs were cloned from single-cell-sorted HA-1 dextramer+ (dexHA-1+) T cells from unstimulated peripheral blood mononuclear cells (PBMCs) and subsequently from CD8 cells cultured with HA-1 peptide-pulsed antigen-presenting cells (APCs). TCRs were re-expressed in reporter cells and analyzed for dextramer binding and CD69 upregulation after culture with peptide-pulsed APCs. TCR sequencing was performed to define CDR3 diversity. 48 dexHA-1+CD8+ T cells were single-cell sorted from 3.9 x10e7 PBMCs of a parous woman. Using TCXpress technology, we cloned 38 TCRs from 48 single-cell dexHA-1+CD8+ T cells. Of these 38, 16 unique TCRs, when expressed in Jurkat cells, were functionally reactive against HA-1(H) peptide by ELISpot. These TCRs had a broad range of EC50s as measured by CD69 upregulation when cultured with HA-1(H) peptide-pulsed T2 cells. CD8+ T cells from the same donor were expanded with autologous HA-1(H)-peptide pulsed APCs for one week. 704 additional TCRs were cloned from dexHA-1+ cells from these cultures. 440 clones were confirmed to bind HA-1 dextramer when expressed in CD8-expressing 293 cells. TCR sequencing of these 440 TCRs identified six additional unique anti-HA-1 TCRs. Several TCRs, when re-expressed in primary CD8+ T cells, killed HA-1+ target cells. TCR sequencing revealed that almost all dexHA-1+ CD8+ T cells used TRBV7-9, consistent with other anti-HA-1 TCR clones in previous reports. In summary, TCXpress technology has yielded 22 unique anti-HA-1 TCRs with a broad functional affinity from a single donor in only two experiments. Our data also highlight the wide range of TCR affinities that can arise from a natural immune response against a single allopeptide/HLA complex. We aim to apply this technology to clone and characterize TCRs against other miHAs, particularly those with expression relatively restricted to hematopoietic cells. Citation Format: Sawa Ito, Constantinos G. Panousis, Alexander M. Rowe, Kedwin Ventura, Jennifer D. Roy, Stephanie Stras, Egidio Brocca-Cofano, Josh Kim, Mark J. Shlomchik, Warren D. Shlomchik. High throughput single-cell based cloning reveals functional diversity of T cell receptors targeting minor histocompatibility antigen [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5189.
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- 2022
12. High Throughput Cloning of T Cell Receptors (TCRs) from Single Cells Reveals That TCRs Recognizing the Minor Histocompatibility Antigen HA-1 Have a Range of Affinities Despite Canonical Beta Chain Usage
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Sawa Ito, Constantinos G Panousis, Alexander M Rowe, Jennifer D Roy, Stephanie Stras, Jianjie Mi, Egidio Brocca-Cofano, Kedwin Ventura, Josh Kim, Mark J Shlomchik, and Warren D. Shlomchik
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Transplantation ,Molecular Medicine ,Immunology and Allergy ,Cell Biology ,Hematology - Published
- 2022
13. Nonhuman Primate Testing of the Impact of Different Regulatory T Cell Depletion Strategies on Reactivation and Clearance of Latent Simian Immunodeficiency Virus
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Adam J. Kleinman, Cristian Apetrei, Cuiling Xu, Benjamin B. Policicchio, Egidio Brocca-Cofano, Ivona Pandrea, Tianyu He, Ranjit Sivanandham, Julia Swarthout, Sindhuja Murali Kilapandal Venkatraman, Paola Sette, and Zhirui Wang
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CD4-Positive T-Lymphocytes ,Primates ,Receptors, CCR4 ,Regulatory T cell ,T cell ,Recombinant Fusion Proteins ,Immunology ,Biology ,CD8-Positive T-Lymphocytes ,medicine.disease_cause ,Microbiology ,T-Lymphocytes, Regulatory ,Virus ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,Immunotoxin ,Virology ,Lymphopenia ,medicine ,Animals ,Diphtheria Toxin ,IL-2 receptor ,030304 developmental biology ,Inflammation ,0303 health sciences ,Immunity, Cellular ,Interleukin-2 Receptor alpha Subunit ,Simian immunodeficiency virus ,Macaca mulatta ,Virus Latency ,medicine.anatomical_structure ,Anti-Retroviral Agents ,030220 oncology & carcinogenesis ,Insect Science ,Cytokines ,Interleukin-2 ,Pathogenesis and Immunity ,Simian Immunodeficiency Virus ,CD8 - Abstract
Regulatory T cells (Tregs) may be key contributors to the HIV/SIV latent reservoir, since they harbor high levels of HIV/SIV; reverse CD4(+) T cell immune activation status, increasing the pool of resting CD4(+) T cells; and impair CD8(+) T cell function, favoring HIV persistence. We tested the hypothesis that Treg depletion is a valid intervention toward an HIV cure by depleted Tregs in 14 rhesus macaque (RM) controllers infected with SIVsab, the virus that naturally infects sabaeus monkeys, through different strategies: administration of an anti-CCR4 immunotoxin, two doses of an anti-CD25 immunotoxin (interleukin-2 with diphtheria toxin [IL-2-DT]), or two combinations of both. All of these treatments resulted in significant depletion of the circulating Tregs (>70%) and their partial depletion in the gut (25%) and lymph nodes (>50%). The fractions of CD4(+) T cells expressing K(i)-67 increased up to 80% in experiments containing IL-2-DT and only 30% in anti-CCR4-treated RMs, paralleled by increases in the inflammatory cytokines. In the absence of ART, plasma virus rebounded to 10(3) vRNA copies/ml by day 10 after IL-2-DT administration. A large but transient boost of the SIV-specific CD8(+) T cell responses occurred in IL-2-DT-treated RMs. Such increases were minimal in the RMs receiving anti-CCR4-based regimens. Five RMs received IL-2-DT on ART, but treatment was discontinued because of high toxicity and lymphopenia. As such, while all treatments depleted a significant proportion of Tregs, the side effects in the presence of ART prevent their clinical use and call for different Treg depletion approaches. Thus, based on our data, Treg targeting as a strategy for HIV cure cannot be discarded. IMPORTANCE Regulatory T cells (Tregs) can decisively contribute to the establishment and persistence of the HIV reservoir, since they harbor high levels of HIV/SIV, increase the pool of resting CD4(+) T cells by reversing their immune activation status, and impair CD8(+) T cell function, favoring HIV persistence. We tested multiple Treg depletion strategies and showed that all of them are at least partially successful in depleting Tregs. As such, Treg depletion appears to be a valid intervention toward an HIV cure, reducing the size of the reservoir, reactivating the virus, and boosting cell-mediated immune responses. Yet, when Treg depletion was attempted in ART-suppressed animals, the treatment had to be discontinued due to high toxicity and lymphopenia. Therefore, while Treg targeting as a strategy for HIV cure cannot be discarded, the methodology for Treg depletion has to be revisited.
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- 2020
14. African green monkeys avoid SIV disease progression by preventing intestinal dysfunction and maintaining mucosal barrier integrity
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Michael Gale, Fredrik Barrenäs, Viskam Wijewardana, Kevin D. Raehtz, Ivona Pandrea, Egidio Brocca-Cofano, Lynn Law, Brandon F. Keele, Anita M. Trichel, Audrey Valentine, Jacob D. Estes, Cristian Apetrei, Kathleen Busman-Sahay, Dongzhu Ma, Cuiling Xu, and Benjamin B. Policicchio
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Male ,RNA viruses ,Simian Acquired Immunodeficiency Syndrome ,HIV Infections ,Pathology and Laboratory Medicine ,Epithelium ,White Blood Cells ,Immunodeficiency Viruses ,Animal Cells ,Interferon ,Chlorocebus aethiops ,Medicine and Health Sciences ,Enteropathy ,Biology (General) ,Intestinal Mucosa ,0303 health sciences ,T Cells ,030302 biochemistry & molecular biology ,virus diseases ,3. Good health ,Jejunum ,medicine.anatomical_structure ,SIV ,Medical Microbiology ,Viral Pathogens ,Viruses ,Disease Progression ,Simian Immunodeficiency Virus ,Pathogens ,Cellular Types ,Anatomy ,medicine.symptom ,Viral load ,Research Article ,medicine.drug ,QH301-705.5 ,Colon ,Immune Cells ,Immunology ,Viremia ,Inflammation ,Research and Analysis Methods ,Microbiology ,Microbiology in the medical area ,Immune Activation ,Epithelial Damage ,03 medical and health sciences ,Virology ,Retroviruses ,Genetics ,medicine ,Mikrobiologi inom det medicinska området ,Animals ,Humans ,Microbial Pathogens ,Immunohistochemistry Techniques ,Molecular Biology ,030304 developmental biology ,Blood Cells ,business.industry ,Lentivirus ,Organisms ,Immunity ,Biology and Life Sciences ,Cell Biology ,RC581-607 ,medicine.disease ,Viral Replication ,Gastrointestinal Microbiome ,Gastrointestinal Tract ,Histochemistry and Cytochemistry Techniques ,Mikrobiologi ,Biological Tissue ,Viral replication ,Bacterial Translocation ,HIV-1 ,Immunologic Techniques ,Parasitology ,Immunologic diseases. Allergy ,business ,Digestive System - Abstract
Unlike HIV infection, SIV infection is generally nonpathogenic in natural hosts, such as African green monkeys (AGMs), despite life-long high viral replication. Lack of disease progression was reportedly based on the ability of SIV-infected AGMs to prevent gut dysfunction, avoiding microbial translocation and the associated systemic immune activation and chronic inflammation. Yet, the maintenance of gut integrity has never been documented, and the mechanism(s) by which gut integrity is preserved are unknown. We sought to investigate the early events of SIV infection in AGMs, specifically examining the impact of SIVsab infection on the gut mucosa. Twenty-nine adult male AGMs were intrarectally infected with SIVsab92018 and serially sacrificed at well-defined stages of SIV infection, preramp-up (1–3 days post-infection (dpi)), ramp-up (4–6 dpi), peak viremia (9–12 dpi), and early chronic SIV infection (46–55 dpi), to assess the levels of immune activation, apoptosis, epithelial damage and microbial translocation in the GI tract and peripheral lymph nodes. Tissue viral loads, plasma cytokines and plasma markers of gut dysfunction were also measured throughout the course of early infection. While a strong, but transient, interferon-based inflammatory response was observed, the levels of plasma markers linked to enteropathy did not increase. Accordingly, no significant increases in apoptosis of either mucosal enterocytes or lymphocytes, and no damage to the mucosal epithelium were documented during early SIVsab infection of AGMs. These findings were supported by RNAseq of the gut tissue, which found no significant alterations in gene expression that would indicate microbial translocation. Thus, for the first time, we confirmed that gut epithelial integrity is preserved, with no evidence of microbial translocation, in AGMs throughout early SIVsab infection. This might protect AGMs from developing intestinal dysfunction and the subsequent chronic inflammation that drives both HIV disease progression and HIV-associated comorbidities., Author summary African nonhuman primates that are natural hosts to SIVs can provide us with unique insight into the pathogenesis of HIV disease due to their remarkable ability to avoid progression to AIDS, despite high levels of viral replication. A key question of SIV pathogenesis in natural hosts is whether the lack of disease progression is due to an exquisite ability to repair lesions occurring during the acute infection or to completely maintain the integrity of the mucosal barrier throughout the SIV infection. In pathogenic HIV/SIV infections of humans and macaques, the mucosal integrity is compromised during acute infection, leading to leakage of gut microbial byproducts and to the occurrence of chronic local and systemic inflammation, which plays a crucial role in driving progression to AIDS. Our study shows that the mucosal barrier integrity is never lost in African green monkeys, thereby avoiding the effects of chronic inflammation and disease progression.
- Published
- 2020
15. Different regimens of romidepsin administration for reversion of SIV latency in a rhesus macaque model of complete virus control
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E. Penn, Angela D. M. Kashuba, S. Murali Kilapandal Venkatraman, M. Cottrell, Ivona Pandrea, Benjamin B. Policicchio, T. Dunsmore, G. Haret-Richter, Cristian Apetrei, Adam J. Kleinman, Ranjit Sivanandham, Paola Sette, John W. Mellors, Chenjie Xu, K. Raehtz, A. Valentine, and Egidio Brocca-Cofano
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biology ,Epidemiology ,business.industry ,Immunology ,Public Health, Environmental and Occupational Health ,Reversion ,biology.organism_classification ,Virology ,Microbiology ,Virus ,QR1-502 ,Romidepsin ,Rhesus macaque ,Infectious Diseases ,Medicine ,Latency (engineering) ,Public aspects of medicine ,RA1-1270 ,business ,medicine.drug - Published
- 2019
16. Marginal Effects of Systemic CCR5 Blockade with Maraviroc on Oral Simian Immunodeficiency Virus Transmission to Infant Macaques
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Karam Musaitif, Dongzhu Ma, Brandon F. Keele, Cuiling Xu, Benjamin B. Policicchio, George S. Haret-Richter, Mackenzie L. Cottrell, Tammy Dunsmore, Cristian Apetrei, Kevin D. Raehtz, Ivona Pandrea, Ronald G. Collman, Egidio Brocca-Cofano, Katherine S. Wetzel, and Angela D. M. Kashuba
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0301 basic medicine ,Serum ,viruses ,Immunology ,Palatine Tonsil ,Clone (cell biology) ,Simian Acquired Immunodeficiency Syndrome ,Viremia ,Biology ,medicine.disease_cause ,Microbiology ,Peripheral blood mononuclear cell ,Virus ,Maraviroc ,03 medical and health sciences ,chemistry.chemical_compound ,Cyclohexanes ,Virology ,Medicine ,Animals ,Humans ,business.industry ,Infant ,virus diseases ,Simian immunodeficiency virus ,Triazoles ,Viral Load ,medicine.disease ,musculoskeletal system ,Macaca mulatta ,Infectious Disease Transmission, Vertical ,Blockade ,body regions ,030104 developmental biology ,medicine.anatomical_structure ,Treatment Outcome ,chemistry ,Insect Science ,Tonsil ,CCR5 Receptor Antagonists ,Pathogenesis and Immunity ,business ,Viral load ,human activities - Abstract
Current approaches do not eliminate all HIV-1 maternal-to-infant transmissions (MTIT); new prevention paradigms might help avert new infections. We administered Maraviroc (MVC) to rhesus macaques (RMs) to block CCR5-mediated entry, followed by repeated oral exposure of a CCR5-dependent clone of simian immunodeficiency virus (SIV)mac251 (SIVmac766). MVC significantly blocked the CCR5 coreceptor in peripheral blood mononuclear cells and tissue cells. All control animals and 60% of MVC-treated infant RMs became infected by the 6th challenge, with no significant difference between the number of exposures (p=0.15). At the time of viral exposures, MVC plasma and tissue (including tonsil) concentrations were within the range seen in humans receiving MVC as a therapeutic. Both treated and control RMs were infected with only a single transmitted/founder variant, consistent with the dose of virus typical of HIV-1 infection. The uninfected RMs expressed the lowest levels of CCR5 on the CD4+ T cells. Ramp-up viremia was significantly delayed (p=0.05) in the MVC-treated RMs, yet peak and postpeak viral loads were similar in treated and control RMs. In conclusion, in spite of apparent effective CCR5 blockade in infant RMs, MVC had marginal impact on acquisition and only a minimal impact on post infection delay of viremia following oral SIV infection. Newly developed, more effective CCR5 blockers may have a more dramatic impact on oral SIV transmission than MVC.ImportanceWe have previously suggested that the very low levels of simian immunodeficiency virus (SIV) maternal-to-infant transmissions (MTIT) in African nonhuman primates that are natural hosts of SIVs are due to a low availability of target cells (CCR5+ CD4+ T cells) in the oral mucosa of the infants, rather than maternal and milk factors. To confirm this new MTIT paradigm, we performed a proof of concept study, in which we therapeutically blocked CCR5 with maraviroc (MVC) and orally exposed MVC treated and naïve infant rhesus macaques to SIV. MVC had only a marginal effect on oral SIV transmission. However, the observation that the infant RMs that remained uninfected at the completion of the study, after 6 repeated viral challenges, had the lowest CCR5 expression on the CD4+ T cells prior to the MVC treatment, appear to confirm our hypothesis, also suggesting that the partial effect of MVC is due to a limited efficacy of the drug. Newly, more effective CCR5 inhibitors may have a better effect in preventing SIV and HIV transmission.
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- 2018
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17. Neutrophil extracellular trap production contributes to pathogenesis in SIV-infected nonhuman primates
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Egidio Brocca-Cofano, Noah Krampe, Ivona Pandrea, Elizabeth Falwell, Cristian Apetrei, Sindhuja Murali Kilapandal Venkatraman, Ranjit Sivanandham, Ruy M. Ribeiro, and Repositório da Universidade de Lisboa
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0301 basic medicine ,CD4-Positive T-Lymphocytes ,Neutrophils ,T cell ,animal diseases ,T cells ,Simian Acquired Immunodeficiency Syndrome ,Biology ,CD8-Positive T-Lymphocytes ,Peripheral blood mononuclear cell ,Extracellular Traps ,Pathogenesis ,AIDS/HIV ,03 medical and health sciences ,Tissue factor ,0302 clinical medicine ,Immune system ,medicine ,Animals ,Platelet ,virus diseases ,General Medicine ,Neutrophil extracellular traps ,030104 developmental biology ,medicine.anatomical_structure ,Anti-Retroviral Agents ,030220 oncology & carcinogenesis ,Immunology ,Simian Immunodeficiency Virus ,Macaca nemestrina ,CD8 ,Research Article - Abstract
Copyright © 2018 American Society for Clinical Investigation, Neutrophil extracellular traps (NETs) are involved in the pathogenesis of many infectious diseases, yet their dynamics and impact on HIV/SIV infection have not yet been assessed. We hypothesized that SIV infection and the related microbial translocation trigger NET activation and release (NETosis), and we investigated the interactions between NETs and immune cell populations and platelets. We compared and contrasted the levels of NETs between SIV-uninfected, SIV-infected, and SIV-infected antiretroviral-treated nonhuman primates. We also cocultured neutrophils from these animals with either peripheral blood mononuclear cells or platelets. Increased NET production was observed throughout SIV infection. In chronically infected animals, NETs were found in the gut, lung, and liver, and in the blood vessels of kidney and heart. Antiretroviral therapy (ART) decreased NETosis, albeit above preinfection levels. NETs captured CD4+ and CD8+ T cells, B cells, and monocytes, irrespective of their infection status, potentially contributing to the indiscriminate generalized immune cell loss characteristic to HIV/SIV infection, and limiting the CD4+ T cell recovery under ART. By capturing and facilitating aggregation of platelets, and through expression of increased tissue factor levels, NETs may also enhance HIV/SIV-related coagulopathy and promote cardiovascular comorbidities., This work was supported by the National Heart, Lung, and Blood Institute/National Institute of Diabetes and Digestive and Kidney Diseases/National Institute of Allergy and Infectious Diseases R01 grants HL117715 and HL123096 (to IP), DK113919 (to IP and CA), AI119346 (to CA), and RR025781 (to CA and IP).
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- 2017
18. Pathogenic Correlates of Simian Immunodeficiency Virus-Associated B Cell Dysfunction
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Cuiling Xu, Celia C. LaBranche, Alan L. Landay, Egidio Brocca-Cofano, David C. Montefiori, Basile Siewe, George S. Haret-Richter, Cristian Apetrei, David Kuhrt, Ivona Pandrea, and Jodi K. Craigo
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0301 basic medicine ,Immunology ,Population ,Naive B cell ,B-Lymphocyte Subsets ,Simian Acquired Immunodeficiency Syndrome ,HIV Infections ,Biology ,medicine.disease_cause ,Antibodies, Viral ,Microbiology ,03 medical and health sciences ,Epitopes ,0302 clinical medicine ,Immune system ,Virology ,Chlorocebus aethiops ,medicine ,Animals ,Humans ,Avidity ,Lymphocyte Count ,Memory B cell ,education ,B cell ,education.field_of_study ,B-Lymphocytes, Regulatory ,T-Lymphocytes, Helper-Inducer ,Simian immunodeficiency virus ,Antibodies, Neutralizing ,Immunity, Humoral ,Interleukin-10 ,030104 developmental biology ,medicine.anatomical_structure ,Insect Science ,biology.protein ,Disease Progression ,Pathogenesis and Immunity ,Simian Immunodeficiency Virus ,Antibody ,Macaca nemestrina ,Immunologic Memory ,030215 immunology - Abstract
We compared and contrasted pathogenic (in pig-tailed macaques [PTMs]) and nonpathogenic (in African green monkeys [AGMs]) SIVsab infections to assess the significance of the B cell dysfunction observed in simian (SIV) and human immunodeficiency virus (HIV) infections. We report that the loss of B cells is specifically associated with the pathogenic SIV infection, while in the natural hosts, in which SIV is nonpathogenic, B cells rapidly increase in both lymph nodes (LNs) and intestine. SIV-associated B cell dysfunction associated with the pathogenic SIV infection is characterized by loss of naive B cells, loss of resting memory B cells due to their redistribution to the gut, increases of the activated B cells and circulating tissue-like memory B cells, and expansion of the B regulatory cells (Bregs). While circulating B cells are virtually restored to preinfection levels during the chronic pathogenic SIV infection, restoration is mainly due to an expansion of the “exhausted,” virus-specific B cells, i.e., activated memory cells and tissue-like memory B cells. Despite of the B cell dysfunction, SIV-specific antibody (Ab) production was higher in the PTMs than in AGMs, with the caveat that rapid disease progression in PTMs was strongly associated with lack of anti-SIV Ab. Neutralization titers and the avidity and maturation of immune responses did not differ between pathogenic and nonpathogenic infections, with the exception of the conformational epitope recognition, which evolved from low to high conformations in the natural host. The patterns of humoral immune responses in the natural host are therefore more similar to those observed in HIV-infected subjects, suggesting that natural hosts may be more appropriate for modeling the immunization strategies aimed at preventing HIV disease progression. The numerous differences between the pathogenic and nonpathogenic infections with regard to dynamics of the memory B cell subsets point to their role in the pathogenesis of HIV/SIV infections and suggest that monitoring B cells may be a reliable approach for assessing disease progression. IMPORTANCE We report here that the HIV/SIV-associated B cell dysfunction (defined by loss of total and memory B cells, increased B regulatory cell [Breg] counts, and B cell activation and apoptosis) is specifically associated with pathogenic SIV infection and absent during the course of nonpathogenic SIV infection in natural nonhuman primate hosts. Alterations of the B cell population are not correlated with production of neutralizing antibodies, the levels of which are similar in the two species. Rapid progressive infections are associated with a severe impairment in SIV-specific antibody production. While we did not find major differences in avidity and maturation between the pathogenic and nonpathogenic SIV infections, we identified a major difference in conformational epitope recognition, with the nonpathogenic infection being characterized by an evolution from low to high conformations. B cell dysfunction should be considered in designing immunization strategies aimed at preventing HIV disease progression.
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- 2017
19. Loss of marginal zone B-cells in SHIVSF162P4 challenged rhesus macaques despite control of viremia to low or undetectable levels in chronic infection
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Katherine M. McKinnon, David Venzon, Thomas Musich, Thorsten Demberg, Marjorie Robert-Guroff, Egidio Brocca-Cofano, and Venkatramanan Mohanram
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Marginal zone B cells ,Lymphoid Tissue ,Simian Acquired Immunodeficiency Syndrome ,Viremia ,CD38 ,Article ,Immunophenotyping ,Antigens, CD ,Virology ,Rhesus macaque ,medicine ,Animals ,Lymphocyte Count ,B cell ,B-Lymphocytes ,CD40 ,biology ,Gene Expression Profiling ,Germinal center ,Marginal zone ,medicine.disease ,Macaca mulatta ,Simian–human immunodeficiency virus infection ,Chronic infection ,Ki-67 Antigen ,medicine.anatomical_structure ,Immunoglobulin M ,Proto-Oncogene Proteins c-bcl-2 ,B cell dysregulation ,Chronic Disease ,Immunology ,biology.protein ,Simian Immunodeficiency Virus ,Antibody - Abstract
Marginal zone (MZ) B cells generate T-independent antibody responses to pathogens before T-dependent antibodies arise in germinal centers. They have been identified in cynomolgus monkeys and monitored during acute SIV infection, yet have not been well-studied in rhesus macaques. Here we characterized rhesus macaque MZ B cells, present in secondary lymphoid tissue but not peripheral blood, as CD19(+), CD20(+), CD21(hi), IgM(+), CD22(+), CD38(+), BTLA(+), CD40(+), CCR6(+) and BCL-2(+). Compared to healthy macaques, SHIVSF162P4-infected animals showed decreased total B cells and MZ B cells and increased MZ B cell Ki-67 expression early in chronic infection. These changes persisted in late chronic infection, despite viremia reductions to low or undetectable levels. Expression levels of additional phenotypic markers and RNA PCR array analyses were in concert with continued low-level activation and diminished function of MZ B cells. We conclude that MZ B-cell dysregulation and dysfunction associated with SIV/HIV infection are not readily reversible.
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- 2015
20. Critical Role for the Adenosine Pathway in Controlling Simian Immunodeficiency Virus-Related Immune Activation and Inflammation in Gut Mucosal Tissues
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Delbert G. Gillespie, Ivona Pandrea, Cristian Apetrei, Jennifer L. Stock, Dongzhu Ma, Egidio Brocca-Cofano, Kevin D. Raehtz, Charles R. Rinaldo, Tianyu He, Bernard J.C. Macatangay, Cuiling Xu, Benjamin B. Policicchio, and Edwin K. Jackson
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Male ,Adenosine ,Dipeptidyl Peptidase 4 ,T-Lymphocytes ,Immunology ,Receptors, Antigen, T-Cell ,Simian Acquired Immunodeficiency Syndrome ,Inflammation ,Biology ,medicine.disease_cause ,Microbiology ,5'-nucleotidase ,Proinflammatory cytokine ,Adenosine deaminase ,Antigen ,Antigens, CD ,Virology ,Chlorocebus aethiops ,medicine ,Animals ,Humans ,5'-Nucleotidase ,Dipeptidyl peptidase-4 ,Apyrase ,Simian immunodeficiency virus ,Insect Science ,Chronic Disease ,biology.protein ,Cytokines ,Pathogenesis and Immunity ,Simian Immunodeficiency Virus ,Macaca nemestrina ,medicine.symptom ,medicine.drug - Abstract
The role of the adenosine (ADO) pathway in human immunodeficiency virus type 1/simian immunodeficiency virus (HIV-1/SIV) infection remains unclear. We compared SIVsab-induced changes of markers related to ADO production (CD39 and CD73) and breakdown (CD26 and adenosine deaminase) on T cells from blood, lymph nodes, and intestine collected from pigtailed macaques (PTMs) and African green monkeys (AGMs) that experience different SIVsab infection outcomes. We also measured ADO and inosine (INO) levels in tissues by mass spectrometry. Finally, we assessed the suppressive effect of ADO on proinflammatory cytokine production after T cell receptor stimulation. The baseline level of both CD39 and CD73 coexpression on regulatory T cells and ADO levels were higher in AGMs than in PTMs. Conversely, high INO levels associated with dramatic increases in CD26 expression and adenosine deaminase activity were observed in PTMs during chronic SIV infection. Immune activation and inflammation markers in the gut and periphery inversely correlated with ADO and directly correlated with INO. Ex vivo administration of ADO significantly suppressed proinflammatory cytokine production by T cells in both species. In conclusion, the opposite dynamics of ADO pathway-related markers and contrasting ADO/INO levels in species with divergent proinflammatory responses to SIV infection support a key role of ADO in controlling immune activation/inflammation in nonprogressive SIV infections. Changes in ADO levels predominately occurred in the gut, suggesting that the ADO pathway may be involved in sparing natural hosts of SIVs from developing SIV-related gut dysfunction. Focusing studies of the ADO pathway on mucosal sites of viral replication is warranted. IMPORTANCE The mechanisms responsible for the severe gut dysfunction characteristic of progressive HIV and SIV infection in humans and macaques are not completely elucidated. We report that ADO may play a key role in controlling immune activation/inflammation in nonprogressive SIV infections by limiting SIV-related gut inflammation. Conversely, in progressive SIV infection, significant degradation of ADO occurs, possibly due to an early increase of ADO deaminase complexing protein 2 (CD26) and adenosine deaminase. Our study supports therapeutic interventions to offset alterations of this pathway during progressive HIV/SIV infections. These potential approaches to control chronic immune activation and inflammation during pathogenic SIV infection may prevent HIV disease progression.
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- 2015
21. Antibody to the gp120 V1/V2 Loops and CD4+ and CD8+ T Cell Responses in Protection from SIVmac251 Vaginal Acquisition and Persistent Viremia
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Guido Ferrari, Shari N. Gordon, Barney S. Graham, Melvin N. Doster, Christopher B. Buck, David C. Montefiori, Michael Piatak, Poonam Pegu, Douglas R. Lowy, Jeffrey D. Lifson, Namal P.M. Liyanage, David Venzon, Monica Vaccari, Nicolas Çuburu, Marjorie Robert-Guroff, Brandon F. Keele, Anastasia Xenophontos, Egidio Brocca-Cofano, John T. Schiller, Rhonda C. Kines, Genoveffa Franchini, and Yongjun Guan
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CD4-Positive T-Lymphocytes ,animal diseases ,viruses ,T cell ,Genetic Vectors ,Molecular Sequence Data ,Immunology ,Simian Acquired Immunodeficiency Syndrome ,Priming (immunology) ,Viremia ,Alphapapillomavirus ,CD8-Positive T-Lymphocytes ,Antibodies, Viral ,Lymphocyte Depletion ,Article ,Virus ,Immune system ,Viral Envelope Proteins ,Antibody Specificity ,T-Lymphocyte Subsets ,Vaccines, DNA ,medicine ,Animals ,Immunology and Allergy ,Cytotoxic T cell ,Mucous Membrane ,biology ,Vaccination ,SAIDS Vaccines ,virus diseases ,medicine.disease ,Macaca mulatta ,Virology ,Peptide Fragments ,Disease Models, Animal ,medicine.anatomical_structure ,Vagina ,biology.protein ,Female ,Simian Immunodeficiency Virus ,Antibody ,CD8 - Abstract
The human papillomavirus pseudovirions (HPV-PsVs) approach is an effective gene-delivery system that can prime or boost an immune response in the vaginal tract of nonhuman primates and mice. Intravaginal vaccination with HPV-PsVs expressing SIV genes, combined with an i.m. gp120 protein injection, induced humoral and cellular SIV-specific responses in macaques. Priming systemic immune responses with i.m. immunization with ALVAC-SIV vaccines, followed by intravaginal HPV-PsV–SIV/gp120 boosting, expanded and/or recruited T cells in the female genital tract. Using a stringent repeated low-dose intravaginal challenge with the highly pathogenic SIVmac251, we show that although these regimens did not demonstrate significant protection from virus acquisition, they provided control of viremia in a number of animals. High-avidity Ab responses to the envelope gp120 V1/V2 region correlated with delayed SIVmac251 acquisition, whereas virus levels in mucosal tissues were inversely correlated with antienvelope CD4+ T cell responses. CD8+ T cell depletion in animals with controlled viremia caused an increase in tissue virus load in some animals, suggesting a role for CD8+ T cells in virus control. This study highlights the importance of CD8+ cells and antienvelope CD4+ T cells in curtailing virus replication and antienvelope V1/V2 Abs in preventing SIVmac251 acquisition.
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- 2014
22. Multimodality vaccination against clade C SHIV: Partial protection against mucosal challenges with a heterologous tier 2 virus
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Marjorie Robert-Guroff, Erwann P. Loret, James G. Else, Sandra J. Lee, Robert A. Rasmussen, Donald N. Forthal, Shannon Stock, Francois Villinger, Mingkui Zhou, Barbara C. Bachler, Victoria R. Polonis, Ruth M. Ruprecht, Welkin E. Johnson, Diego A. Vargas-Inchaustegui, Egidio Brocca Cofano, Girish Hemashettar, Siddappa N. Byrareddy, Shiu Lok Hu, and Samir K. Lakhashe
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Cellular immunity ,animal diseases ,viruses ,Gene Products, gag ,Heterologous ,Viremia ,HIV Antibodies ,Biology ,medicine.disease_cause ,Gene Products, nef ,Article ,Virus ,HIV Envelope Protein gp160 ,Immune system ,medicine ,Animals ,HIV vaccine ,Immunity, Mucosal ,AIDS Vaccines ,Immunity, Cellular ,Vaccines, Synthetic ,General Veterinary ,General Immunology and Microbiology ,Vaccination ,Public Health, Environmental and Occupational Health ,virus diseases ,Simian immunodeficiency virus ,medicine.disease ,Antibodies, Neutralizing ,Macaca mulatta ,Virology ,Recombinant Proteins ,Immunity, Humoral ,Infectious Diseases ,Immunology ,HIV-1 ,Molecular Medicine ,Simian Immunodeficiency Virus ,tat Gene Products, Human Immunodeficiency Virus - Abstract
We sought to test whether vaccine-induced immune responses could protect rhesus macaques (RMs) against upfront heterologous challenges with an R5 simian-human immunodeficiency virus, SHIV-2873Nip. This SHIV strain exhibits many properties of transmitted HIV-1, such as tier 2 phenotype (relatively difficult to neutralize), exclusive CCR5 tropism, and gradual disease progression in infected RMs. Since no human AIDS vaccine recipient is likely to encounter an HIV-1 strain that exactly matches the immunogens, we immunized the RMs with recombinant Env proteins heterologous to the challenge virus. For induction of immune responses against Gag, Tat, and Nef, we explored a strategy of immunization with overlapping synthetic peptides (OSP). The immune responses against Gag and Tat were finally boosted with recombinant proteins. The vaccinees and a group of ten control animals were given five low-dose intrarectal (i.r.) challenges with SHIV-2873Nip. All controls and seven out of eight vaccinees became systemically infected; there was no significant difference in viremia levels of vaccinees vs. controls. Prevention of viremia was observed in one vaccinee which showed strong boosting of virus-specific cellular immunity during virus exposures. The protected animal showed no challenge virus-specific neutralizing antibodies in the TZM-bl or A3R5 cell-based assays and had low-level ADCC activity after the virus exposures. Microarray data strongly supported a role for cellular immunity in the protected animal. Our study represents a case of protection against heterologous tier 2 SHIV-C by vaccine-induced, virus-specific cellular immune responses.
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- 2014
23. Inflammatory monocytes expressing tissue factor drive SIV and HIV coagulopathy
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George H. Richter, Irini Sereti, Egidio Brocca-Cofano, Ivo M.B. Francischetti, Cristian Apetrei, Alan Sher, Amrit Singh, Melissa E. Schechter, Ruy M. Ribeiro, Ivona Pandrea, Dongying Ma, Kevin W. Tosh, Russel Tracy, Bruno B. Andrade, Tianyu He, Virginia Sheikh, Kevin D. Raehtz, Benjamin B. Policicchio, and Repositório da Universidade de Lisboa
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Lipopolysaccharides ,0301 basic medicine ,Lipopolysaccharide Receptors ,Simian Acquired Immunodeficiency Syndrome ,ComputingMilieux_LEGALASPECTSOFCOMPUTING ,HIV Infections ,Inflammation ,Biology ,Antibodies, Viral ,medicine.disease_cause ,Monocytes ,Thromboplastin ,Proinflammatory cytokine ,03 medical and health sciences ,Tissue factor ,Chlorocebus aethiops ,medicine ,Animals ,Humans ,Receptor, PAR-1 ,GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries) ,Blood Coagulation ,Innate immune system ,Monocyte ,General Medicine ,Pigtail macaque ,Blood Coagulation Disorders ,Simian immunodeficiency virus ,biology.organism_classification ,Editorial ,030104 developmental biology ,medicine.anatomical_structure ,Anti-Retroviral Agents ,Chronic Disease ,Immunology ,Cytokines ,Simian Immunodeficiency Virus ,Tumor necrosis factor alpha ,Inflammation Mediators ,medicine.symptom ,Signal Transduction - Abstract
Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. http://www.sciencemag.org/about/science-licenses-journal-article-reuseThis is an article distributed under the terms of the Science Journals Default License, In HIV infection, persistent inflammation despite effective antiretroviral therapy is linked to increased risk of noninfectious chronic complications such as cardiovascular and thromboembolic disease. A better understanding of inflammatory and coagulation pathways in HIV infection is needed to optimize clinical care. Markers of monocyte activation and coagulation independently predict morbidity and mortality associated with non-AIDS events. We identified a specific subset of monocytes that express tissue factor (TF), persist after virological suppression, and trigger the coagulation cascade by activating factor X. This subset of monocytes expressing TF had a distinct gene signature with up-regulated innate immune markers and evidence of robust production of multiple proinflammatory cytokines, including interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and IL-6, ex vivo and in vitro upon lipopolysaccharide stimulation. We validated our findings in a nonhuman primate model, showing that TF-expressing inflammatory monocytes were associated with simian immunodeficiency virus (SIV)-related coagulopathy in the progressive [pigtail macaques (PTMs)] but not in the nonpathogenic (African green monkeys) SIV infection model. Last, Ixolaris, an anticoagulant that inhibits the TF pathway, was tested and potently blocked functional TF activity in vitro in HIV and SIV infection without affecting monocyte responses to Toll-like receptor stimulation. Strikingly, in vivo treatment of SIV-infected PTMs with Ixolaris was associated with significant decreases in D-dimer and immune activation. These data suggest that TF-expressing monocytes are at the epicenter of inflammation and coagulation in chronic HIV and SIV infection and may represent a potential therapeutic target., This study was supported by the NIH Intramural Research Program, National Institute of Allergy and Infectious Diseases, and Bench-to-Bedside award R01HL117715-10S1 (to I.S. and I.P.). Part of this project has been also funded with federal funds from the National Cancer Institute, NIH, under contract no. HHSN261200800001E. The NHP study has also been funded in part with federal funds from the NIH (R01 HL123096 and RO1 HL117715 to I.P., R01 AI119346 to C.A., and R01AI104373 to R.M.R.).
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- 2017
24. Modeling Aging in HIV Infection in Nonhuman Primate Models to Address an Emerging Challenge of the post-ART Era
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Elizabeth Falwell, Ivona Pandrea, Egidio Brocca-Cofano, and Tianyu He
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0301 basic medicine ,Senescence ,Human immunodeficiency virus (HIV) ,Biology ,medicine.disease_cause ,medicine.disease ,Virus ,Article ,Pathogenesis ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Immune system ,Acquired immunodeficiency syndrome (AIDS) ,Immunity ,Virology ,Immunology ,medicine ,030212 general & internal medicine ,Pathological - Abstract
The advent of antiretroviral therapy (ART) has dramatically improved both quality and length of life for subjects infected with human immunodeficiency virus (HIV), delaying or preventing progression to acquired immunodeficiency syndrome (AIDS). However, the virus induces aging-related changes to the immune system which confound treatment. Additionally, the normal physiologic events that occur during aging lead to deficiencies in immunity which not only exacerbate HIV pathogenesis but also trigger a variety of comorbidities. Here, the synergistic linkage between aging and HIV infection is examined in regard to the immunological and pathological mechanisms that drive both senescence and disease progression. The use of NHPs to investigate potential therapeutic strategies to control the deleterious consequences of aging with HIV infection is also reviewed.
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- 2017
25. Immune targeting of PD-1hi expressing cells during and after antiretroviral therapy in SIV-infected rhesus macaques
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Solomon Langermann, Eun Mi Lee, Katherine McKinnon, Thorsten Demberg, Alison Hogg, Linda Liu, Lauren Hudacik, Yongjun Sui, Peng Xiao, Janet DiPasquale, Ranajit Pal, David Venzon, Jay A. Berzofsky, Marjorie Robert-Guroff, Diego A. Vargas-Inchaustegui, and Egidio Brocca-Cofano
- Subjects
medicine.medical_treatment ,T cell ,T-Lymphocytes ,Programmed Cell Death 1 Receptor ,Simian Acquired Immunodeficiency Syndrome ,Viremia ,Biology ,Peripheral blood mononuclear cell ,Article ,Immunomodulation ,Antigen ,Antiretroviral Therapy, Highly Active ,Virology ,PD-1 ,medicine ,Animals ,Immunologic Factors ,Immunotherapy ,Viral Load ,medicine.disease ,Macaca mulatta ,Treg ,medicine.anatomical_structure ,Anti-Retroviral Agents ,Immunology ,Lymph ,Viral load ,CD8 ,ART - Abstract
High-level T cell expression of PD-1 during SIV infection is correlated with impaired proliferation and function. We evaluated the phenotype and distribution of T cells and Tregs during antiretroviral therapy plus PD-1 modulation (using a B7-DC-Ig fusion protein) and post-ART. Chronically SIV-infected rhesus macaques received: 11 weeks of ART (Group A); 11 weeks of ART plus B7-DC-Ig (Group B); 11 weeks of ART plus B7-DC-Ig, then 12 weeks of B7-DC-Ig alone (Group C). Continuous B7-DC-Ig treatment (Group C) decreased rebound viremia post-ART compared to pre-ART levels, associated with decreased PD-1(hi) expressing T cells and Tregs in PBMCs, and PD-1(hi) Tregs in lymph nodes. It transiently decreased expression of Ki67 and α4β7 in PBMC CD4(+) and CD8(+) Tregs for up to 8 weeks post-ART and maintained Ag-specific T-cell responses at low levels. Continued immune modulation targeting PD-1(hi) cells during and post-ART helps maintain lower viremia, keeps a favorable T cell/Treg repertoire and modulates antigen-specific responses.
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- 2013
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26. Impact of antibody quality and anamnestic response on viremia control post-challenge in a combined Tat/Env vaccine regimen in rhesus macaques
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Diego A. Vargas-Inchaustegui, Indresh K. Srivastava, David Venzon, Eun Mi Lee, Vaniambadi S. Kalyanaraman, David C. Montefiori, Janet DiPasquale, Thorsten Demberg, Irene Kalisz, Ruth M. Ruprecht, Stanley Aladi, Susan W. Barnett, Seraphin Kuate, Ranajit Pal, Marjorie Robert-Guroff, and Egidio Brocca-Cofano
- Subjects
HIV vaccine ,HIV Tat ,viruses ,Simian Acquired Immunodeficiency Syndrome ,chemical and pharmacologic phenomena ,Viremia ,Antibodies, Viral ,Article ,03 medical and health sciences ,0302 clinical medicine ,Adjuvants, Immunologic ,Virology ,Rhesus macaque ,SHIV challenge ,medicine ,Animals ,Humans ,Avidity ,Alum adjuvant ,Neutralizing antibody ,030304 developmental biology ,0303 health sciences ,biology ,Immunogenicity ,SAIDS Vaccines ,Gene Products, env ,virus diseases ,medicine.disease ,Antibodies, Neutralizing ,Macaca mulatta ,3. Good health ,HIV Envelope ,Gene Products, tat ,Immunology ,Humoral immunity ,biology.protein ,Alum Compounds ,Simian Immunodeficiency Virus ,Antibody ,ADCC ,Immunologic Memory ,030215 immunology - Abstract
Previously, priming rhesus macaques with Adenovirus type 5 host range mutant-recombinants encoding Tat and Env and boosting with Tat and Env protein in MPL-SE controlled chronic viremia by 4 logs following homologous intravenous SHIV89.6P challenge. Here we evaluated Tat, Env, and Tat/Env regimens for immunogenicity and protective efficacy using clade C Env, alum adjuvant, and a heterologous intrarectal SHIV1157ipd3N4 challenge. Despite induction of strong cellular and humoral immunity, Tat/Env group T and B-cell memory responses were not significantly enhanced over Tat- or Env-only groups. Lack of viremia control post-challenge was attributed to lower avidity Env antibodies and no anamnestic ADCC response or SHIV1157ipd3N4 neutralizing antibody development post-challenge. Poor biologic activity of the Tat immunogen may have impaired Tat immunity. In the absence of sterilizing immunity, strong anamnestic responses to heterologous virus can help control viremia. Both antibody breadth and optimal adjuvanticity are needed to elicit high-quality antibody for protective efficacy.
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- 2013
27. Dynamics of Memory B-Cell Populations in Blood, Lymph Nodes, and Bone Marrow during Antiretroviral Therapy and Envelope Boosting in Simian Immunodeficiency Virus SIVmac251-Infected Rhesus Macaques
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Katherine McKinnon, Vaniambadi S. Kalyanaraman, Thorsten Demberg, Marjorie Robert-Guroff, Irene Kalisz, Egidio Brocca-Cofano, Eun Mi Lee, Diego A. Vargas-Inchaustegui, David Venzon, Peng Xiao, and Janet DiPasquale
- Subjects
CD4-Positive T-Lymphocytes ,Male ,Plasma Cells ,Immunology ,Simian Acquired Immunodeficiency Syndrome ,Bone Marrow Cells ,Biology ,medicine.disease_cause ,Microbiology ,Macaque ,CD19 ,Viral Envelope Proteins ,Virology ,biology.animal ,medicine ,Animals ,Memory B cell ,Analysis of Variance ,B-Lymphocytes ,Membrane Glycoproteins ,Germinal center ,Viral Load ,Simian immunodeficiency virus ,Flow Cytometry ,Macaca mulatta ,medicine.anatomical_structure ,Anti-Retroviral Agents ,Insect Science ,Linear Models ,biology.protein ,Pathogenesis and Immunity ,Simian Immunodeficiency Virus ,Lymph Nodes ,Bone marrow ,Lymph ,Immunologic Memory ,Viral load - Abstract
Human immunodeficiency virus (HIV)/simian immunodeficiency virus (SIV) infection causes B-cell dysregulation and the loss of memory B cells in peripheral blood mononuclear cells (PBMC). These effects are not completely reversed by antiretroviral treatment (ART). To further elucidate B-cell changes during chronic SIV infection and treatment, we investigated memory B-cell subpopulations and plasma cells/plasmablasts (PC/PB) in blood, bone marrow, and lymph nodes of rhesus macaques during ART and upon release from ART. Macaques previously immunized with SIV recombinants and the gp120 protein were included to assess the effects of prior vaccination. ART was administered for 11 weeks, with or without gp120 boosting at week 9. Naïve and resting, activated, and tissue-like memory B cells and PC/PB were evaluated by flow cytometry. Antibody-secreting cells (ASC) and serum antibody titers were assessed. No lasting changes in B-cell memory subpopulations occurred in bone marrow and lymph nodes, but significant decreases in numbers of activated memory B cells and increases in numbers of tissue-like memory B cells persisted in PBMC. Macaque PC/PB were found to be either CD27 + or CD27 − and therefore were defined as CD19 + CD38 hi CD138 + . The numbers of these PC/PB were transiently increased in both PBMC and bone marrow following gp120 boosting of the unvaccinated and vaccinated macaque groups. Similarly, ASC numbers in PBMC and bone marrow of the two macaque groups also transiently increased following envelope boosting. Nevertheless, serum binding titers against SIVgp120 remained unchanged. Thus, even during chronic SIV infection, B cells respond to antigen, but long-term memory does not develop, perhaps due to germinal center destruction. Earlier and/or prolonged treatment to allow the generation of virus-specific long-term memory B cells should benefit ART/therapeutic vaccination regimens.
- Published
- 2012
28. Multi-dose Romidepsin Reactivates Replication Competent SIV in Post-antiretroviral Rhesus Macaque Controllers
- Author
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Ranjit Sivanandham, George S. Haret-Richter, Hui Li, Dongzhu Ma, Ivona Pandrea, Kevin D. Raehtz, Beatrice H. Hahn, Anita M. Trichel, George M. Shaw, Tianyu He, Cristian Apetrei, John W. Mellors, Ruy M. Ribeiro, Cuiling Xu, Benjamin B. Policicchio, Tammy Dunsmore, and Egidio Brocca-Cofano
- Subjects
0301 basic medicine ,Time Factors ,Physiology ,Simian Acquired Immunodeficiency Syndrome ,CD8-Positive T-Lymphocytes ,Virus Replication ,Romidepsin ,White Blood Cells ,0302 clinical medicine ,Animal Cells ,Immune Physiology ,Depsipeptides ,Medicine and Health Sciences ,Cytotoxic T cell ,Public and Occupational Health ,030212 general & internal medicine ,Biology (General) ,Immune Response ,Innate Immune System ,T Cells ,Vaccination and Immunization ,3. Good health ,Infectious Diseases ,medicine.anatomical_structure ,Anti-Retroviral Agents ,Cytokines ,RNA, Viral ,Simian Immunodeficiency Virus ,Cellular Types ,Research Article ,medicine.drug ,Infectious Disease Control ,QH301-705.5 ,Immune Cells ,T cell ,Immunology ,Antiretroviral Therapy ,Cytotoxic T cells ,Viremia ,Biology ,Microbiology ,Virus ,Immune Activation ,03 medical and health sciences ,Immune system ,Antiviral Therapy ,Virology ,Genetics ,medicine ,Animals ,Molecular Biology ,Blood Cells ,Immunity ,Biology and Life Sciences ,Cell Biology ,Molecular Development ,RC581-607 ,medicine.disease ,Macaca mulatta ,Viral Replication ,030104 developmental biology ,Viral replication ,Immune System ,Parasitology ,Preventive Medicine ,Immunologic diseases. Allergy ,CD8 ,Developmental Biology - Abstract
Viruses that persist despite seemingly effective antiretroviral treatment (ART) and can reinitiate infection if treatment is stopped preclude definitive treatment of HIV-1 infected individuals, requiring lifelong ART. Among strategies proposed for targeting these viral reservoirs, the premise of the “shock and kill” strategy is to induce expression of latent proviruses [for example with histone deacetylase inhibitors (HDACis)] resulting in elimination of the affected cells through viral cytolysis or immune clearance mechanisms. Yet, ex vivo studies reported that HDACis have variable efficacy for reactivating latent proviruses, and hinder immune functions. We developed a nonhuman primate model of post-treatment control of SIV through early and prolonged administration of ART and performed in vivo reactivation experiments in controller RMs, evaluating the ability of the HDACi romidepsin (RMD) to reactivate SIV and the impact of RMD treatment on SIV-specific T cell responses. Ten RMs were IV-infected with a SIVsmmFTq transmitted-founder infectious molecular clone. Four RMs received conventional ART for >9 months, starting from 65 days post-infection. SIVsmmFTq plasma viremia was robustly controlled to, Author Summary Antiretroviral therapy (ART) does not eradicate HIV-1 in infected individuals due to virus persistence in latently infected reservoir cells, despite apparently effective ART. The persistent virus and can rekindle infection when ART is interrupted. The goal of the “shock and kill” viral clearance strategy is to induce expression of latent proviruses and eliminate the infected cells through viral cytolysis or immune clearance mechanisms. Latency reversing agents (LRAs) tested to date have been reported to have variable effects, both on virus reactivation and on immune functions. We performed in vivo reactivation experiments in SIV-infected RMs that controlled viral replication after a period of ART to evaluate the ability of the histone deacetylase inhibitor romidepsin (RMD) to reactivate SIV and its impact on SIV-specific immune responses. Our results suggest that RMD treatment can increase virus expression in this setting, and that it does not markedly or durably impair the ability of SIV-specific T cells to control viral replication.
- Published
- 2016
29. Envelope residue 375 substitutions in simian–human immunodeficiency viruses enhance CD4 binding and replication in rhesus macaques
- Author
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Gerald H. Learn, Brandon F. Keele, Xingpei Hao, Jason Gorman, Sampa Santra, Ben Policicchio, Jeffrey D. Lifson, Barton F. Haynes, Claire Deleage, Hui Li, Gwo-Yu Chuang, Georgia D. Tomaras, Xiaoying Shen, Ivona Pandrea, Jacob D. Estes, Wenge Ding, Paul Hahn, George M. Shaw, Shuyi Wang, Hua-Xin Liao, Beatrice H. Hahn, Peter Kwong, Cristian Apetrei, Theodora Hatziioannou, Eunlim Kim, Robert W. Doms, Michael Farzan, Zahra F. Parker, Rui Kong, Egidio Brocca-Cofano, Fang Hua Lee, David C. Montefiori, Mark G. Lewis, Matthew R. Gardner, Joseph Sodroski, S. Munir Alam, and Elena Chertova
- Subjects
0301 basic medicine ,Antigenicity ,viruses ,030106 microbiology ,Mutation, Missense ,Simian Acquired Immunodeficiency Syndrome ,HIV Infections ,medicine.disease_cause ,Virus Replication ,Neutralization ,03 medical and health sciences ,Viral entry ,medicine ,Animals ,Humans ,Neutralizing antibody ,Immunodeficiency ,Multidisciplinary ,biology ,env Gene Products, Human Immunodeficiency Virus ,virus diseases ,Simian immunodeficiency virus ,medicine.disease ,Virology ,Macaca mulatta ,030104 developmental biology ,Viral replication ,PNAS Plus ,Amino Acid Substitution ,CD4 Antigens ,biology.protein ,HIV-1 ,Simian Immunodeficiency Virus ,Antibody - Abstract
Most simian-human immunodeficiency viruses (SHIVs) bearing envelope (Env) glycoproteins from primary HIV-1 strains fail to infect rhesus macaques (RMs). We hypothesized that inefficient Env binding to rhesus CD4 (rhCD4) limits virus entry and replication and could be enhanced by substituting naturally occurring simian immunodeficiency virus Env residues at position 375, which resides at a critical location in the CD4-binding pocket and is under strong positive evolutionary pressure across the broad spectrum of primate lentiviruses. SHIVs containing primary or transmitted/founder HIV-1 subtype A, B, C, or D Envs with genotypic variants at residue 375 were constructed and analyzed in vitro and in vivo. Bulky hydrophobic or basic amino acids substituted for serine-375 enhanced Env affinity for rhCD4, virus entry into cells bearing rhCD4, and virus replication in primary rhCD4 T cells without appreciably affecting antigenicity or antibody-mediated neutralization sensitivity. Twenty-four RMs inoculated with subtype A, B, C, or D SHIVs all became productively infected with different Env375 variants-S, M, Y, H, W, or F-that were differentially selected in different Env backbones. Notably, SHIVs replicated persistently at titers comparable to HIV-1 in humans and elicited autologous neutralizing antibody responses typical of HIV-1. Seven animals succumbed to AIDS. These findings identify Env-rhCD4 binding as a critical determinant for productive SHIV infection in RMs and validate a novel and generalizable strategy for constructing SHIVs with Env glycoproteins of interest, including those that in humans elicit broadly neutralizing antibodies or bind particular Ig germ-line B-cell receptors.
- Published
- 2016
30. Replicating Adenovirus-Simian Immunodeficiency Virus (SIV) Recombinant Priming and Envelope Protein Boosting Elicits Localized, Mucosal IgA Immunity in Rhesus Macaques Correlated with Delayed Acquisition following a Repeated Low-Dose Rectal SIV mac251 Challenge
- Author
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Marjorie Robert-Guroff, Jun Zhao, Brandon F. Keele, Seraphin Kuate, Peng Xiao, David C. Montefiori, Eun Mi Lee, Vaniambadi S. Kalyanaraman, Irene Kalisz, Claudio Fenizia, Michael A. Thomas, Janet DiPasquale, David Venzon, L. Jean Patterson, Egidio Brocca-Cofano, and Ranajit Pal
- Subjects
Antibody-dependent cell-mediated cytotoxicity ,Cellular immunity ,Immunology ,chemical and pharmacologic phenomena ,Viremia ,Simian immunodeficiency virus ,Biology ,medicine.disease_cause ,medicine.disease ,Microbiology ,Virology ,Macaque ,Immunity ,Insect Science ,biology.animal ,Humoral immunity ,medicine ,Avidity - Abstract
We have shown that sequential replicating adenovirus type 5 host range mutant human immunodeficiency virus/simian immunodeficiency virus (HIV/SIV) recombinant priming delivered first intranasally (i.n.) plus orally and then intratracheally (i.t.), followed by envelope protein boosting, elicits broad cellular immunity and functional, envelope-specific serum and mucosal antibodies that correlate with protection from high-dose SIV and simian/human immunodeficiency virus (SHIV) challenges in rhesus macaques. Here we extended these studies to compare the standard i.n./i.t. regimen with additional mucosal administration routes, including sublingual, rectal, and vaginal routes. Similar systemic cellular and humoral immunity was elicited by all immunization routes. Central and effector memory T cell responses were also elicited by the four immunization routes in bronchoalveolar lavage fluid and jejunal, rectal, and vaginal tissue samples. Cellular responses in vaginal tissue were more compartmentalized, being induced primarily by intravaginal administration. In contrast, all immunization routes elicited secretory IgA (sIgA) responses at multiple mucosal sites. Following a repeated low-dose intrarectal (i.r.) challenge with SIV mac251 at a dose transmitting one or two variants, protection against acquisition was not achieved except in one macaque in the i.r. immunized group. All immunized macaques exhibited reduced peak viremia compared to that of controls, correlated inversely with prechallenge serum antienvelope avidity, antibody-dependent cellular cytotoxicity (ADCC) titers, and percent antibody-dependent cell-mediated viral inhibition. Both antibody avidity and ADCC titers were correlated with the number of exposures required for infection. Notably, we show for the first time a significant correlation of vaccine-induced sIgA titers in rectal secretions with delayed acquisition. Further investigation of the characteristics and properties of the sIgA should elucidate the mechanism leading to this protective effect.
- Published
- 2012
31. Vaccine-elicited SIV and HIV envelope-specific IgA and IgG memory B cells in rhesus macaque peripheral blood correlate with functional antibody responses and reduced viremia
- Author
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L. Jean Patterson, Peng Xiao, Rachmat Hidajat, David Venzon, Thorsten Demberg, Mara Daltabuit-Test, Egidio Brocca-Cofano, Marjorie Robert-Guroff, and Katherine McKinnon
- Subjects
Enzyme-Linked Immunospot Assay ,Naive B cell ,Priming (immunology) ,Article ,Immunoglobulin G ,Viral Envelope Proteins ,medicine ,Animals ,Viremia ,Memory B cell ,B cell ,B-Lymphocytes ,CD40 ,General Veterinary ,General Immunology and Microbiology ,biology ,Public Health, Environmental and Occupational Health ,HIV ,Flow Cytometry ,Acquired immune system ,Macaca mulatta ,Virology ,Immunoglobulin A ,B-1 cell ,Infectious Diseases ,medicine.anatomical_structure ,Immunology ,biology.protein ,Molecular Medicine ,Simian Immunodeficiency Virus ,Immunologic Memory - Abstract
An effective HIV vaccine requires strong systemic and mucosal, cellular and humoral immunity. Numerous non-human primate studies have investigated memory T cells, but not memory B cells. Humoral immunologic memory is mediated by long-lived antibody-secreting plasma cells and differentiation of memory B cells into short-lived plasma blasts following re-exposure to immunizing antigen. Here we studied memory B cells in vaccinated rhesus macaques. PBMC were stimulated polyclonally using CD40 Ligand, IL-21 and CpG to induce B cell proliferation and differentiation into antibody secreting cells (ASC). Flow cytometry was used for phenotyping and evaluating proliferation by CFSE dilution. B cell responses were quantified by ELISPOT. Methodology was established using PBMC of vaccinated elite-controller macaques that exhibited strong, multi-functional antibody activities. Subsequently, memory B cells elicited by two replicating Ad-recombinant prime/envelope boost regimens were retrospectively evaluated pre- and post- SIV and SHIV challenges. The vaccine regimens induced SIV and HIV Env-specific IgG and IgA memory B cells. Prior to challenge, IgA memory B cells were more numerous than IgG memory B cells, reflecting the mucosal priming immunizations. Pre- and post-challenge memory B cells were correlated with functional antibody responses including antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cell-mediated viral inhibition (ADCVI) and transcytosis inhibition. Post-challenge, Env-specific IgG and IgA memory B cells were correlated with reduced chronic viremia. We conclude that functional antibody responses elicited by our prime/boost regimen were effectively incorporated into the memory B cell pool where they contributed to control of viremia following re-exposure to the immunizing antigen.
- Published
- 2011
32. Multiple Vaccine-Elicited Nonneutralizing Antienvelope Antibody Activities Contribute to Protective Efficacy by Reducing both Acute and Chronic Viremia following Simian/Human Immunodeficiency Virus SHIV89.6PChallenge in Rhesus Macaques
- Author
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Thorsten Demberg, Peng Xiao, Pamela A. Kozlowski, Rachmat Hidajat, David Venzon, L. Jean Patterson, Marjorie Robert-Guroff, Egidio Brocca-Cofano, and Jun Zhao
- Subjects
Male ,Immunology ,Immunization, Secondary ,Simian Acquired Immunodeficiency Syndrome ,HIV Infections ,Viremia ,HIV Antibodies ,medicine.disease_cause ,Microbiology ,Virus ,Virology ,Vaccines and Antiviral Agents ,medicine ,Animals ,Humans ,Avidity ,AIDS Vaccines ,Antibody-dependent cell-mediated cytotoxicity ,biology ,Rectum ,SAIDS Vaccines ,Gene Products, env ,HIV ,virus diseases ,Virus Internalization ,Simian immunodeficiency virus ,biology.organism_classification ,medicine.disease ,Macaca mulatta ,Transcytosis ,Insect Science ,Lentivirus ,biology.protein ,Immunization ,Simian Immunodeficiency Virus ,Antibody - Abstract
We have shown that following priming with replicating adenovirus type 5 host range mutant (Ad5hr)-human immunodeficiency virus (HIV)/simian immunodeficiency virus (SIV) recombinants, boosting with gp140 envelope protein enhances acute-phase protection against intravenous simian/human immunodeficiency virus (SHIV)89.6Pchallenge compared to results with priming and no boosting or boosting with an HIV polypeptide representing the CD4 binding site of gp120. We retrospectively analyzed antibodies in sera and rectal secretions from these same macaques, investigating the hypothesis that vaccine-elicited nonneutralizing antibodies contributed to the better protection. Compared to other immunized groups or controls, the gp140-boosted group exhibited significantly greater antibody activities mediating antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cell-mediated viral inhibition (ADCVI) in sera and transcytosis inhibition in rectal secretions. ADCC and ADCVI activities were directly correlated with antibody avidity, suggesting the importance of antibody maturation for functionality. Both ADCVI and percent ADCC killing prechallenge were significantly correlated with reduced acute viremia. The latter, as well as postchallenge ADCVI and ADCC, was also significantly correlated with reduced chronic viremia. We have previously demonstrated induction by the prime/boost regimen of mucosal antibodies that inhibit transcytosis of SIV across an intact epithelial cell layer. Here, antibody in rectal secretions was significantly correlated with transcytosis inhibition. Importantly, the transcytosis specific activity (percent inhibition/total secretory IgA and IgG) was strongly correlated with reduced chronic viremia, suggesting that mucosal antibody may help control cell-to-cell viral spread during the course of infection. Overall, the replicating Ad5hr-HIV/SIV priming/gp140 protein boosting approach elicited strong systemic and mucosal antibodies with multiple functional activities associated with control of both acute and chronic viremia.
- Published
- 2010
33. Interferon regulatory factor-1 acts as a powerful adjuvant in tat DNA based vaccination
- Author
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Giulia Marsili, Anna Lisa Remoli, Angela Battistini, Marco Sgarbanti, Arianna Castaldello, Antonella Caputo, and Egidio Brocca-Cofano
- Subjects
Cytotoxic ,Physiology ,Interferon Regulatory Factor-7 ,T-Lymphocytes ,medicine.medical_treatment ,Clinical Biochemistry ,Biology ,AIDS Vaccines ,Animals ,Cell Line ,Cysteine Endopeptidases ,Female ,HIV-1 ,Humans ,Immunization ,Interferon Regulatory Factor-1 ,Interferon Regulatory Factor-3 ,Mice ,T-Lymphocytes, Cytotoxic ,Vaccines, DNA ,Adjuvants, Immunologic ,tat Gene Products, Human Immunodeficiency Virus ,Cell Biology ,NO ,DNA vaccination ,Immune system ,Antigen ,Immunologic ,medicine ,Adjuvants ,Vaccines ,Immunogenicity ,DNA ,Virology ,Vaccination ,IRF1 ,Immunology ,tat Gene Products ,Adjuvant ,Human Immunodeficiency Virus - Abstract
Genetic vaccines are safe cost-effective approaches to immunization but DNA immunization is an inefficient process. There is, therefore, a pressing need for adjuvants capable of enhancing the immunogenicity and effectiveness of these vaccines. This is particularly important for diseases for which successful vaccines are still lacking, such as cancer and infectious diseases including HIV-1/AIDS. Here we report an approach to enhance the immunogenicity of DNA vaccines involving the use of transcription factors of the Interferon regulatory factor (IRF) family, specifically IRF-1, IRF-3, and IRF-7 using the tat gene as model antigen. Balb/c mice were immunized by three intramuscular inoculations, using a DNA prime-protein boost protocol, with a DNA encoding tat of HIV-1 and the indicated IRFs and immune responses were compared to those induced by vaccination with tat DNA alone. In vivo administration of plasmid DNA encoding IRF-1, or a mutated version of IRF-1 deleted of the DNA-binding domain, enhanced Tat-specific immune responses and shifted them towards a predominant T helper 1-type immune response with increased IFN-gamma production and cytotoxic T lymphocytes responses. Conversely, the use of IRF-3 or IRF-7 did not affect the tat-induced responses. These findings define IRF-1 and its mutated form as efficacious T helper 1-inducing adjuvants in the context of tat-based vaccination and also providing a new promising candidate for genetic vaccine development.
- Published
- 2010
34. Priming with a very low dose of DNA complexed with cationic block copolymers followed by protein boost elicits broad and long-lasting antigen-specific humoral and cellular responses in mice
- Author
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Barbara Ensoli, Luisa Tondelli, Michele Laus, Egidio Brocca-Cofano, Katia Sparnacci, Riccardo Gavioli, Antonella Caputo, Rita De Michele, Arianna Castaldello, Rebecca Voltan, Chiara Triulzi, Eva Reali, and Giuseppe Altavilla
- Subjects
Prime-boost ,HIV Antigens ,Polymers ,Priming (immunology) ,HIV Antibodies ,Biology ,DNA vaccination ,Injections, Intramuscular ,Mice ,chemistry.chemical_compound ,Immune system ,Adjuvants, Immunologic ,Cationic block copolymers ,Cations ,Vaccines, DNA ,Animals ,Cytotoxic T cell ,Cell Proliferation ,AIDS Vaccines ,Immunity, Cellular ,Mice, Inbred BALB C ,General Veterinary ,General Immunology and Microbiology ,Public Health, Environmental and Occupational Health ,Th1 Cells ,Molecular biology ,CTL ,Infectious Diseases ,chemistry ,Naked DNA ,Immunoglobulin G ,Humoral immunity ,Cytokines ,Molecular Medicine ,Female ,tat Gene Products, Human Immunodeficiency Virus ,Epitope Mapping ,Spleen ,DNA ,T-Lymphocytes, Cytotoxic - Abstract
Cationic block copolymers spontaneously assemble via electrostatic interactions with DNA molecules in aqueous solution giving rise to micellar structures that protect the DNA from enzymatic degradation both in vitro and in vivo. In addition, we have previously shown that they are safe, not immunogenic and greatly increased antigen-specific CTL responses following six intramuscular inoculations of a very low dose (1microg) of the vaccine DNA as compared to naked DNA. Nevertheless, they failed to elicit detectable humoral responses against the antigen. To gain further insight in the potential application of this technology, here we show that a shorter immunization protocol based on two DNA intramuscular inoculations of 1microg of DNA delivered by these copolymers and a protein boost elicits in mice broad (both humoral and cellular) and long-lasting responses and increases the antigen-specific Th1-type T cell responses and CTLs as compared to priming with naked DNA. These results indicate that cationic block copolymers represent a promising adjuvant and delivery technology for DNA vaccination strategies aimed at combating intracellular pathogens.
- Published
- 2009
35. The Tat protein broadens T cell responses directed to the HIV-1 antigens Gag and Env: Implications for the design of new vaccination strategies against AIDS
- Author
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Chiara Triulzi, Rebecca Voltan, Riccardo Gavioli, Indresh K. Srivastava, Aurelio Cafaro, Cinzia Fortini, Francesca Gagliardoni, Arianna Castaldello, Antonella Caputo, Barbara Ensoli, Susan W. Barnett, Eleonora Gallerani, Egidio Brocca Cofano, and Silvia Cellini
- Subjects
Cellular immunity ,Subdominant ,Ovalbumin ,T cell ,AIDS ,Vaccine ,Tat ,Epitopes, T-Lymphocyte ,HIV Envelope Protein gp120 ,Major histocompatibility complex ,Epitope ,NO ,Epitopes ,Mice ,Species Specificity ,Antigen ,medicine ,Animals ,Cells, Cultured ,AIDS Vaccines ,General Veterinary ,General Immunology and Microbiology ,biology ,env Gene Products, Human Immunodeficiency Virus ,Public Health, Environmental and Occupational Health ,Th1 Cells ,biology.organism_classification ,Virology ,Mice, Inbred C57BL ,CTL ,Infectious Diseases ,medicine.anatomical_structure ,Immunology ,Lentivirus ,HIV-1 ,biology.protein ,Molecular Medicine ,Immunization ,tat Gene Products, Human Immunodeficiency Virus ,Spleen ,T-Lymphocytes, Cytotoxic - Abstract
We have previously shown that the biologically active Tat protein targets and efficiently enters dendritic cells, and increases the proteolytic activities of the immunoproteasome, thereby favoring the generation and presentation of the subdominant MHC-I binding CTL epitopes of heterologous antigens. In the present study, we demonstrate that Tat broadens in vivo epitope-specific T cell responses directed to heterologous antigens including HIV structural proteins. Specifically, co-immunization of mice with OVA and Tat proteins induces CTL responses against subdominant and cryptic OVA-derived epitopes, which are not detected in mice vaccinated with OVA alone. Similarly, mice vaccinated with the HIV-1 Gag, Env or V2-deleted Env antigens in combination with Tat show Th1-type and CTL responses directed to a larger number of T cell epitopes, as compared to mice vaccinated with these proteins in absence of Tat. In contrast, Tat did not affect Th2-type responses to these structural HIV proteins. These results indicate that Tat is not only an antigen but also a novel Th1-type adjuvant capable of broadening in vivo the spectrum of epitopes recognized by T cells, and suggest that Tat can be considered an optimal co-antigen in the development of novel vaccination strategies against AIDS.
- Published
- 2008
36. Preparation and Characterization of Innovative Protein-coated Poly(Methylmethacrylate) Core-shell Nanoparticles for Vaccine Purposes
- Author
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Arianna Castaldello, Rebecca Voltan, Silvia Spaccasassi, Luisa Tondelli, Barbara Ensoli, Egidio Brocca-Cofano, Katia Sparnacci, Antonella Caputo, Michele Laus, Marco Ballestri, and Giuseppe Altavilla
- Subjects
Protein Denaturation ,Time Factors ,Cell Survival ,Chemistry, Pharmaceutical ,Drug Compounding ,Acrylic Resins ,Pharmaceutical Science ,Nanoparticle ,Emulsion polymerization ,Mice ,chemistry.chemical_compound ,Drug Stability ,Polymer chemistry ,medicine ,Animals ,Humans ,Polymethyl Methacrylate ,Trypsin ,Pharmacology (medical) ,Surface charge ,Particle Size ,Microparticle ,AIDS Vaccines ,Pharmacology ,Drug Carriers ,Immunity, Cellular ,Dose-Response Relationship, Drug ,Chemistry ,Organic Chemistry ,Mice, Inbred C57BL ,Solubility ,Covalent bond ,Antibody Formation ,Biophysics ,Nanoparticles ,Molecular Medicine ,Female ,Muramidase ,tat Gene Products, Human Immunodeficiency Virus ,Lysozyme ,Drug carrier ,Oxidation-Reduction ,Vaccine ,HeLa Cells ,Protein Binding ,Biotechnology ,medicine.drug - Abstract
Purpose. This study aims at developing novel core-shell poly(methylmethacrylate) (PMMA) nanoparticles as a delivery system for protein vaccine candidates. Materials and Methods. Anionic nanoparticles consisting of a core of PMMA and a shell deriving from Eudragit L100/55 were prepared by an innovative synthetic method based on emulsion polymerization. The formed nanoparticles were characterized for size, surface charge and ability to reversibly bind two basic model proteins (Lysozyme, Trypsin) and a vaccine relevant antigen (HIV-1 Tat), by means of cell-free studies. Their in vitro toxicity and capability to preserve the biological activity of the HIV-1 Tat protein were studied in cell culture systems. Finally, their safety and immunogenicity were investigated in the mouse model. Results. The nanoparticles had smooth surface, spherical shape and uniform size distribution with a mean diameter of 220 nm. The shell is characterized by covalently bound carboxyl groups negatively charged at physiological pH, able to reversibly adsorb large amounts (up to 20% w/w) of basic proteins (Lysozyme, Trypsin and HIV-1 Tat), mainly through specific electrostatic interactions. The nanoparticles were stable, not toxic to the cells, protected the HIV-1 Tat protein from oxidation, thus preserving its biological activity and increasing its shelf-life, and efficiently delivered and released it intracellularly. In vivo experiments showed that they are well tolerated and elicit strong immune responses against the delivered antigen in mice. Conclusions. This study demonstrates that these new nanoparticles provide a versatile platform for protein surface adsorption and a promising delivery system particularly when the maintenance of the biologically active conformation is required for vaccine efficacy.
- Published
- 2007
37. Red blood cell-mediated delivery of recombinant HIV-1 Tat protein in mice induces anti-Tat neutralizing antibodies and CTL
- Author
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Mauro Magnani, Barbara Ensoli, Sabrina Dominici, Giordano Serafini, Maria Elena Laguardia, Egidio Brocca-Cofano, Valeria Fiorelli, Riccardo Gavioli, Arianna Scoglio, Laura Chiarantini, Cinzia Fortini, Antonella Tripiciano, Antonella Caputo, and Aurelio Cafaro
- Subjects
Antibodies, Viral ,Transplantation, Autologous ,law.invention ,Mice ,law ,medicine ,Animals ,Cytotoxic T cell ,Biotinylation ,Immunization Schedule ,AIDS Vaccines ,General Veterinary ,General Immunology and Microbiology ,biology ,Public Health, Environmental and Occupational Health ,hemic and immune systems ,biology.organism_classification ,Virology ,Molecular biology ,Recombinant Proteins ,Red blood cell ,Cytolysis ,CTL ,Infectious Diseases ,medicine.anatomical_structure ,Antibody Formation ,Gene Products, tat ,Lentivirus ,HIV-1 ,biology.protein ,Recombinant DNA ,Molecular Medicine ,tat Gene Products, Human Immunodeficiency Virus ,Antibody ,Erythrocyte Transfusion ,T-Lymphocytes, Cytotoxic - Abstract
The immunotherapeutic potential of biologically active HIV-1 Tat protein coupled to autologous red blood cells (RBCs) was evaluated in a mouse model. HIV-1 Tat expressed in Escherichia coli and purified to homogeneity was found to be active in viral trans activation and efficiently internalised by monocyte-derived dendritic cells (MDDCs). The product of HIV-Tat biotinylation and coupling to RBCs by means of a biotin–avidin–biotin bridge, (RBC-Tat), showed no trans activation activity and was still efficiently internalized by MDDCs as compared to uncoupled Tat. Balb/c mice were then immunized with 10g of soluble Tat in complete Freund’s adjuvant or with 40 ng of Tat coupled on RBCs surface and boosted at week 3, 6 and 25 with 5g soluble Tat in incomplete Freund’s adjuvant or with 20 ng of RBC-coupled Tat, respectively. Anti-Tat antibody response was similar in both groups; however, 2/6 animals immunized with soluble Tat and 6/6 animals immunized with RBC-Tat developed anti-Tat neutralizing antibodies. In addition, at week 28 cytolytic anti-Tat CTLs were detected in all animals although they were slightly higher in mice immunized with RBC-Tat. These results indicate that RBC-mediated delivery of HIV-1 Tat, in amounts 250 times lower than soluble Tat, is safe and induces specific CTL responses and neutralizing antibodies. © 2002 Elsevier Science Ltd. All rights reserved.
- Published
- 2003
38. Increased excitability in tat-transgenic mice: Role of tat in HIV-related neurological disorders
- Author
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Giuseppe Barbanti-Brodano, Michele Simonato, Pierangelo Cifelli, Rita De Michele, Giuseppe Altavilla, Maria Summa, Egidio Brocca-Cofano, M. Fabris, Angela Bonaccorsi, Alfredo Corallini, Graziella Busatto, Silvia Zucchini, Anna Pittaluga, Antonella Caputo, and Gianluca Verlengia
- Subjects
Male ,Hippocampus ,Kainate receptor ,Transgenic ,Mice ,Economica ,Vesicular Glutamate Transport Proteins ,HIV-1 associated neurocognitive disorders ,HIV-1-tat-transgenic mice ,kainate ,neurodegeneration ,seizures ,analysis of variance ,animals ,brain ,Kainate ,Neurodegeneration ,Seizures ,Analysis of Variance ,Animals ,Brain ,Disease Models, Animal ,Dose-Response Relationship, Drug ,Gene Products, tat ,Kainic Acid ,Mice, Transgenic ,Nervous System Diseases ,Neurotransmitter Agents ,Statistics, Nonparametric ,tat Gene Products, Human Immunodeficiency Virus ,tat ,Statistics ,Glutamate receptor ,Neurology ,Drug ,tat Gene Products ,Human Immunodeficiency Virus ,Genetically modified mouse ,medicine.medical_specialty ,Socio-culturale ,Biology ,Exocytosis ,lcsh:RC321-571 ,Dose-Response Relationship ,Internal medicine ,medicine ,Gene Products ,Nonparametric ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Animal ,medicine.disease ,Cortex (botany) ,Endocrinology ,Disease Models ,Convulsant ,Neuroscience - Abstract
HIV-1 associated neurocognitive disorders (HAND) are a major complication of HIV-1 infection. The mechanism(s) underlying HAND are not completely understood but, based on in vitro studies, the HIV-1 Tat protein may play an important role. In this study, the effect of prolonged exposure to endogenously produced Tat in the brain was investigated using a tat-transgenic (TT) mouse model constitutively expressing the HIV-1 tat gene. We found that stimulus-evoked glutamate exocytosis in the hippocampus and cortex was significantly increased in TT as compared with wild-type control (CC) mice, while GABA exocytosis was unchanged in the hippocampus and decreased in the cortex. This suggests that Tat generates a latent hyper-excitability state, which favors the detrimental effects of neurotoxic and/or excitotoxic agents. To challenge this idea, TT mice were tested for susceptibility to kainate-induced seizures and neurodegeneration, and found to exhibit significantly greater responses to the convulsant agent than CC mice. These results support the concept that constitutive expression of tat in the brain generates a latent excitatory state, which may increase the negative effects of damaging insults. These events may play a key role in the development of HAND.
- Published
- 2013
39. HIV Envelope-Specific Antibody and Vaccine Efficacy
- Author
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Peng Xiao, Egidio Brocca-Cofano, and Marjorie Robert-Guroff
- Subjects
Antibody-dependent cell-mediated cytotoxicity ,Cellular immunity ,biology ,business.industry ,HIV envelope protein ,Vaccine efficacy ,Virology ,Vaccination ,Immunity ,biology.protein ,Medicine ,HIV vaccine ,business ,Neutralizing antibody - Abstract
Following transmission, the human immunodeficiency virus (HIV) initiates persistent infection by integrating into the genome of host cells. To date it has not been possible to clear these cells by anti-viral or immune therapy, during either active or latent infection. This makes design of an efficacious HIV vaccine exceedingly difficult, since complete prevention of infection, or “sterilizing immunity”, is required. As cellular immunity targets already infected cells, humoral immune responses which can prevent initial infection by means of anti-envelope neutralizing antibodies have been a prime focus of vaccine development. In proof of concept studies, passive administration of potent neutralizing antibodies has prevented infection of non-human primates by intravenous and mucosal routes (Mascola et al., 1999; Baba et al., 2000; Mascola et al., 2000; Parren et al., 2001), validating the research focus on neutralizing antibody induction. However, the task of designing an envelope vaccine is complicated by the extreme variability among HIV isolates, the propensity for neutralization escape resulting from immune pressure exerted by induced antibodies, conformational features of the HIV envelope which make immunogen design difficult, and additional envelope characteristics which effectively hide areas of vulnerability which might ordinarily be antibody targets. There are several excellent recent reviews covering the issue of broadly neutralizing antibodies (Mascola & Montefiori, 2010; Walker & Burton, 2010; Zolla-Pazner & Cardozo, 2010; McElrath & Haynes, 2010) and it is not the intent of this review to reproduce that information. Rather, we will briefly summarize some of the salient issues and approaches, and then discuss more extensively non-neutralizing anti-envelope antibodies. Broadly neutralizing antibodies are difficult to elicit by vaccination. But the HIV envelope protein is quite immunogenic, and an array of non-neutralizing antibodies is induced by both natural infection and vaccination. Through use of sensitive new methods, these antibodies have exhibited several functional activities associated with protection. In serum these include antibody-dependent cellular cytotoxicity (ADCC) (Weinhold, 1990) and antibody-dependent cell mediated viral inhibition (ADCVI) (Forthal et al., 2006). Secretory antibodies have also been associated with protection via mechanisms such as transcytosis inhibition (Bomsel et al., 1998). Augmented by high avidity and recall memory responses which improve their efficacy, these antibody activities can contribute in varying degrees to vaccine-induced protective efficacy. The main thrust of this review will be to examine these
- Published
- 2011
40. Early Short-Term Antiretroviral Therapy Is Associated with a Reduced Prevalence of CD8+FoxP3+ T Cells in Simian Immunodeficiency Virus-Infected Controller Rhesus Macaques
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Joseph J. Mattapallil, Mark K. Louder, John R. Mascola, Elizabeth A. Lybarger, Egidio Brocca Cofano, Jeffy George, Bernard A. P. Lafont, and Marjorie Robert-Guroff
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Anti-HIV Agents ,animal diseases ,CD8 Antigens ,Immunology ,Simian Acquired Immunodeficiency Syndrome ,chemical and pharmacologic phenomena ,Pathogenesis ,Biology ,medicine.disease_cause ,T-Lymphocytes, Regulatory ,Virus ,Interleukin 21 ,Immune system ,Virology ,Antiretroviral Therapy, Highly Active ,medicine ,Immune Tolerance ,Cytotoxic T cell ,Animals ,FOXP3 ,Forkhead Transcription Factors ,T lymphocyte ,Simian immunodeficiency virus ,Macaca mulatta ,Infectious Diseases ,CD8 - Abstract
Regulatory T cells contain a mix of CD4 and CD8 T cell subsets that can suppress immune activation and at the same time suppress immune responses, thereby contributing to disease progression. Recent studies have shown that an increased prevalence of CD8(+)FoxP3(+) T regulatory cells was associated with immune suppression and diminished viral control in simian immunodeficiency virus (SIV)-infected rhesus macaques. Preventing an increase in the prevalence of CD8 T regulatory subsets is likely to lead to a better long-term outcome. Here we show that short-term antiretroviral therapy initiated within 1 week after SIV infection was associated with lower viral set point and immune activation after withdrawal of therapy as compared to untreated animals. Early short-term treated controller animals were found to have better SIV-specific immune responses and a significantly lower prevalence of immunosuppressive CD8(+)FoxP3(+) T cells. Lower levels of CD8(+)FoxP3(+) T cells coincided with preservation of CD4(+)FoxP3(+) T cells at homeostatic levels, and significantly correlated with lower immune activation, suggesting a role for viral infection-driven immune activation in the expansion of CD8(+)FoxP3(+) T cells. Interestingly, initiation of continuous therapy later in infection did not reduce the increased prevalence of CD8(+)FoxP3(+) T cells to homeostatic levels. Taken together, our results suggest that early antiretroviral therapy preserves the integrity of the immune system leading to a lower viral set point in controller animals, and prevents alterations in the homeostatic balance between CD4(+) and CD8(+) T regulatory cells that could aid in better long-term outcome.
- Published
- 2011
41. Rapid SIV Env-specific mucosal and serum antibody induction augments cellular immunity in protecting immunized, elite-controller macaques against high dose heterologous SIV challenge
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L. Jean Patterson, Egidio Brocca-Cofano, Roger W. Wiseman, Marjorie Robert-Guroff, Robert A. Seder, Vaniambadi S. Kalyanaraman, Ulrike Wille-Reece, Ranajit Pal, Stephen Whitney, Jun Zhao, Irene Kalisz, Satya Dandekar, Peng Xiao, David C. Montefiori, Vanessa M. Hirsch, Mario Roederer, Eun Mi Lee, William K. Hu, and Mara Daltabuit-Test
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Serum ,Cellular immunity ,animal diseases ,T-Lymphocytes ,Simian Acquired Immunodeficiency Syndrome ,Heterologous ,Viremia ,Biology ,medicine.disease_cause ,Antibodies, Viral ,Macaque ,Virus ,Article ,Memory ,Virology ,biology.animal ,medicine ,Animals ,Immunity, Mucosal ,Immunity, Cellular ,virus diseases ,Simian immunodeficiency virus ,medicine.disease ,Antibodies, Neutralizing ,Macaca mulatta ,medicine.anatomical_structure ,Jejunum ,SIV ,Immunology ,Humoral immunity ,Virus sequestration ,Simian Immunodeficiency Virus ,Lymph Nodes ,Elite-control ,Multifaceted immunity ,Vaccine ,Memory T cell - Abstract
Three Indian rhesus macaques, Ad-SIV primed/protein boosted and exposed twice to high-dose mucosal SIV mac251 challenges, exhibited elite control of viremia over 6.5 years. They were negative for host factors associated with control of SIV infection. After a third intrarectal challenge with SIV smE660 , all controlled viremia, with one (macaque #5) maintaining undetectable viremia in blood. Acquisition was not blocked, but virus was contained in the jejunum and draining lymph nodes. Polyfunctional memory T cell responses and high-titered neutralizing and non-neutralizing serum and mucosal antibodies were present before and maintained post-challenge. The level of protection seen for animal #5 was predicted from analyses of gene transcription in jejunum 2 weeks post-challenge. Macaques #7 and #9, exhibiting lower pre-challenge cellular and humoral immunity, partially controlled the SIV smE660 challenge. Initial vaccine-induced control by macaque #5 extended to the SIV smE660 challenge due to multiple immune mechanisms that were boosted and augmented by cryptic SIV exposure.
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- 2010
42. The increase in intra-macrophage thiols induced by new pro-GSH molecules directs the Th1 skewing in ovalbumin immunized mice
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Maria Filomena Paoletti, Michael Smietana, Egidio Brocca-Cofano, Enrico Millo, Umberto Benatti, Sabrina Dominici, Mauro Magnani, Alessandra Fraternale, Antonella Caputo, Pascal Clayette, Joel Oiry, and Arianna Castaldello
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Immunology and Microbiology (all) ,Inbred C57BL ,Mice ,chemistry.chemical_compound ,Immunologic ,Cells, Cultured ,Immunity, Cellular ,Mice, Inbred ICR ,Cultured ,biology ,ELISPOT ,Inbred ICR ,Glutathione ,Infectious Diseases ,Interleukin 12 ,Veterinary (all) ,Molecular Medicine ,Female ,Public Health ,Macrophage redox state ,Oxidation-Reduction ,Ovalbumin ,Cells ,Pro-GSH molecules ,Th1/Th2 responses ,Adjuvants, Immunologic ,Animals ,Antibody Formation ,Immunoglobulin G ,Macrophages, Peritoneal ,Mice, Inbred C57BL ,Sulfhydryl Compounds ,Th2 Cells ,Public Health, Environmental and Occupational Health ,NO ,Immune system ,In vivo ,Peritoneal ,Splenocyte ,Adjuvants ,General Veterinary ,General Immunology and Microbiology ,Macrophage redox state, Th1/Th2 responses, Pro-GSH molecules ,Macrophages ,Environmental and Occupational Health ,Immunity ,Molecular biology ,In vitro ,chemistry ,biology.protein ,Cellular - Abstract
In the present work, the capacity of new pro-GSH molecules to increase the intra-macrophage thiol content in vitro and in vivo as well as to shift the immune response to Th1 in ovalbumin (Ova)-sensitized mice were examined. The molecules were the N-butanoyl GSH derivative, GSH-C4, and a pro-drug of N-acetylcysteine (NAC) and beta-mercaptoethylamine (MEA), I-152. In vitro, 2 h-incubation with both molecules was found to increase intra-macrophage thiol content; in vivo, Ova-sensitized mice pre-treated by intraperitoneal administration of the pro-GSH molecules showed an increase in plasma anti-Ova IgG2a and IgG2b, characterizing Th1 immune response, and a decrease in IgG1, typical of the Th2 response. Such findings were connected to a shift to a Th1 response also involving splenocyte IFN-γ production as revealed by ELISPOT assay and higher levels of IL-12 in circulation. Although immune responses are in vivo mediated both by dendritic cells and macrophages, the data reported in this paper corroborate the suggestion that the pro-GSH molecules, increasing the intra-cellular thiol pool, modulate the Th1/Th2 balance favouring Th1-type responses and may be employed as Th1-directing adjuvants in new vaccination protocols and as immunomodulators in those diseases where Th1 response patterns are compromised in favour of Th2.
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- 2010
43. Induction of humoral and enhanced cellular immune responses by novel core-shell nanosphere- and microsphere-based vaccine formulations following systemic and mucosal administration
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Luisa Tondelli, Rebecca Voltan, Antonella Caputo, Michele Laus, Arianna Castaldello, Francesca Bortolazzi, Barbara Ensoli, Egidio Brocca-Cofano, Riccardo Gavioli, Giuseppe Altavilla, and Katia Sparnacci
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Cellular immunity ,Biology ,Pharmacology ,HIV Antibodies ,Microbiology ,NO ,Interferon-gamma ,Mice ,Immune system ,Antigen ,Immunity ,Animals ,Alum adjuvant ,Immunity, Mucosal ,AIDS Vaccines ,Mice, Inbred BALB C ,General Veterinary ,General Immunology and Microbiology ,Immunogenicity ,Public Health, Environmental and Occupational Health ,Microspheres ,Infectious Diseases ,Humoral immunity ,Molecular Medicine ,Nasal administration ,Female ,Immunization ,Interleukin-4 ,Nanospheres - Abstract
Anionic surfactant-free polymeric core-shell nanospheres and microspheres were previously described with an inner core constituted by poly(methylmethacrylate) (PMMA) and a highly hydrophilic outer shell composed of a hydrosoluble co-polymer (Eudragit L100-55). The outer shell is tightly linked to the core and bears carboxylic groups capable of adsorbing high amounts (antigen loading ability of up to 20%, w/w) of native basic proteins, mainly by electrostatic interactions, while preserving their activity. In the present study we have evaluated in mice the safety and immunogenicity of new vaccine formulations composed of these nano- and microspheres and the HIV-1 Tat protein. Vaccines were administered by different routes, including intramuscular, subcutaneous or intranasal and the results were compared to immunization with Tat alone or with Tat delivered with the alum adjuvant. The data demonstrate that the nano- and microspheres/Tat formulations are safe and induce robust and long-lasting cellular and humoral responses in mice after systemic and/or mucosal immunization. These delivery systems may have great potential for novel Tat protein-based vaccines against HIV-1 and hold promise for other protein-based vaccines.
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- 2009
44. Identification of new HIV-1 Gag-specific cytotoxic T lymphocyte responses in BALB/c mice
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Silvia Cellini, Riccardo Gavioli, Federica Destro, Egidio Brocca Cofano, Eleonora Gallerani, Antonella Caputo, and Cinzia Fortini
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viruses ,T cell ,Molecular Sequence Data ,Short Report ,motifs ,Epitopes, T-Lymphocyte ,Gene Products, gag ,HIV Infections ,Biology ,Epitope ,lcsh:Infectious and parasitic diseases ,NO ,cell responses, TAT protein, peptides, epitopes, viremia, motifs ,Mice ,cell responses ,Immune system ,Antigen ,TAT protein ,Virology ,medicine ,Animals ,Cytotoxic T cell ,lcsh:RC109-216 ,Amino Acid Sequence ,AIDS Vaccines ,Mice, Inbred BALB C ,viremia ,epitopes ,Cytotoxicity Tests, Immunologic ,CTL ,Infectious Diseases ,medicine.anatomical_structure ,Epitope mapping ,Gene Products, tat ,Immunology ,HIV-1 ,peptides ,Epitope Mapping ,CD8 ,T-Lymphocytes, Cytotoxic - Abstract
BackgroundAs HIV-specific cytotoxic T cells play a key role during acute and chronic HIV-1 infection in humans, the ability of potential anti-HIV vaccines to elicit strong, broad T cell responses is likely to be crucial. The HIV-1 Gag antigen is widely considered a relevant antigen for the development of an anti-HIV vaccine since it is one of the most conserved viral proteins and is also known to induce T cell responses. In the majority of studies reporting Gag-specific cellular immune responses induced by Gag-based vaccines, only a small number of Gag T cell epitopes were tested in preclinical mouse models, thus giving an incomplete picture of the numerous possible cellular immune responses against this antigen. As is, this partial knowledge of epitope-specific T cell responses directed to Gag will unavoidably result in a limited preclinical evaluation of Gag-based vaccines.ResultsIn this study we identified new Gag CD8+ T cell epitopes in BALB/c mice vaccinated with the HIV-1 Gag antigen alone or in combination with the HIV-1 Tat protein, which was recently shown to broaden T cell responses directed to Gag. Specifically, we found that CTL responses to Gag may be directed to nine different CTL epitopes, and four of these were mapped as minimal CTL epitopes.ConclusionThese newly identified CTL epitopes should be considered in the preclinical evaluation of T cell responses induced by Gag-based vaccines in mice.
- Published
- 2008
45. Characterization of immune responses elicited in mice by intranasal co-immunization with HIV-1 Tat, gp140 DeltaV2Env and/or SIV Gag proteins and the nontoxicogenic heat-labile Escherichia coli enterotoxin
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Indresh K. Srivastava, Arianna Castaldello, Egidio Brocca-Cofano, Riccardo Gavioli, Aurelio Cafaro, Barbara Ensoli, Susan W. Barnett, Antonella Caputo, and Rebecca Voltan
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T-Lymphocytes ,Bacterial Toxins ,Gene Products, gag ,HIV Infections ,HIV Antibodies ,Enterotoxins ,Mice ,Immune system ,Antigen ,Adjuvants, Immunologic ,Immunity ,Animals ,Humans ,Immunity, Mucosal ,Administration, Intranasal ,Glycoproteins ,AIDS Vaccines ,Mice, Inbred BALB C ,General Veterinary ,General Immunology and Microbiology ,biology ,Escherichia coli Proteins ,Vaccination ,Public Health, Environmental and Occupational Health ,biology.organism_classification ,Virology ,Infectious Diseases ,Immunization ,Lentivirus ,Immunology ,Gene Products, tat ,biology.protein ,HIV-1 ,Molecular Medicine ,Female ,Simian Immunodeficiency Virus ,Antibody ,Viral load - Abstract
The development of a vaccine against HIV/AIDS capable of inducing broad humoral and cellular responses at both systemic and mucosal sites, able to stop or reduce viral infection at the portal of entry, represents the only realistic way to control the infection caused by HIV world-wide. The promising results obtained with the HIV-1 Tat-based vaccines in preclinical and clinical settings, the evidence that a broad immunity against HIV correlates with reduced viral load or virus control, as well as the availability of novel gp140 V2-loop deleted HIV-1 Env (DeltaV2Env) immunogens capable of inducing cross-reactive neutralizing antibodies, have led to the design of new vaccine strategies based on the combination of non-structural and structural proteins. In this study, we demonstrate that immunization with a biologically active HIV-1 Tat protein in combination with the oligomeric HIV-1 gp140 DeltaV2Env and/or SIV Gag proteins, delivered intranasally with the detoxified LTK63 mucosal adjuvant, whose safety has been recently shown in humans, elicits long-lasting local and systemic antibody and cellular immune responses against the co-administered antigens in a fashion similar to immune responses induced by vaccination with Tat, DeltaV2Env and Gag proteins alone. The results indicate lack of antigen interference implying that HIV-1 Tat is an optimal co-antigen for combined vaccine strategies employing DeltaV2Env and/or Gag proteins.
- Published
- 2007
46. DNA prime and protein boost immunization with innovative polymeric cationic core-shell nanoparticles elicits broad immune responses and strongly enhance cellular responses of HIV-1 tat DNA vaccination
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Giuseppe Altavilla, Katia Sparnacci, Chiara Triulzi, Riccardo Gavioli, Luisa Tondelli, Rebecca Voltan, Barbara Ensoli, Cinzia Fortini, Marco Ballestri, Antonella Caputo, Arianna Castaldello, Michele Laus, and Egidio Brocca-Cofano
- Subjects
Cellular immunity ,Polymers ,Immunization, Secondary ,Biology ,HIV Antibodies ,DNA vaccination ,Polyethylene Glycols ,chemistry.chemical_compound ,Mice ,Immune system ,Plasmid ,Drug Delivery Systems ,In vivo ,Cations ,Vaccines, DNA ,Animals ,Polymethyl Methacrylate ,Immunization Schedule ,AIDS Vaccines ,Mice, Inbred BALB C ,General Veterinary ,General Immunology and Microbiology ,Vaccination ,Public Health, Environmental and Occupational Health ,Cationic polymerization ,Th1 Cells ,Molecular biology ,In vitro ,Nanostructures ,Infectious Diseases ,chemistry ,Gene Products, tat ,Biophysics ,HIV-1 ,Molecular Medicine ,Female ,tat Gene Products, Human Immunodeficiency Virus ,DNA ,T-Lymphocytes, Cytotoxic - Abstract
Novel biocompatible core-shell cationic nanoparticles, composed of an inner hard core of poly(methylmethacrylate) (PMMA) and a hydrophilic tentacular shell bearing positively charged groups and poly(ethyleneglycol) chains covalently bound to the core, were prepared by emulsion polymerization and characterized in vitro and in vivo for DNA vaccine applications. The nanoparticles reversibly adsorbed large amounts of DNA, mainly through electrostatic interactions, preserved its functional structure, efficiently delivered it intracellularly, and were not toxic in vitro or in mice. Furthermore, two intramuscular (i.m.) immunizations (4 weeks apart) with a very low dose (1 mu g) of the plasmid pCV-tat delivered by these nanoparticles followed by one or two protein boosts induced significant antigen-specific humoral and cellular responses and greatly increased Th1-type T cell responses and CTLs against HIV-1 Tat. (c) 2006 Elsevier Ltd. All rights reserved.
- Published
- 2006
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47. Inhibition of human immunodeficiency virus type 1 tat-trans-activation-responsive region interaction by an antiviral quinolone derivative
- Author
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Arnaldo Fravolini, Sara N. Richter, Barbara Gatto, Giorgio Palù, Egidio Brocca-Cofano, Manlio Palumbo, Cristina Parolin, and Claudia Del Vecchio
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HIV-1 INFECTION ,Molecular Sequence Data ,ANTI-HIV AGENTS ,QUINOLONES ,Biology ,medicine.disease_cause ,Antiviral Agents ,Virus ,Tar (tobacco residue) ,In vivo ,Ciprofloxacin ,medicine ,Pharmacology (medical) ,Pyrroles ,Amino Acid Sequence ,Antibacterial agent ,HIV Long Terminal Repeat ,Pharmacology ,Mutation ,RNA ,Isoquinolines ,Molecular biology ,In vitro ,Infectious Diseases ,DNA, Viral ,Gene Products, tat ,HIV-1 ,RNA, Viral ,tat Gene Products, Human Immunodeficiency Virus ,Plasmids - Abstract
WM5, a 6-aminoquinolone derivative, binds with high affinity to the bulge of the trans -activation-responsive region (TAR), whereas it displays low binding affinity for the loop and stem regions of TAR and for random RNA and DNA sequences. Furthermore, WM5 disrupts the natural protein-nucleic acid complex with a 50% inhibitory concentration in the low micromolar range in both in vitro and in vivo assays.
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- 2004
48. Novel biocompatible anionic polymeric microspheres for the delivery of the HIV-1 Tat protein for vaccine application
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Barbara Ensoli, Antonella Caputo, Arianna Castaldello, Laura Chiarantini, Marco Marchisio, Aurelio Cafaro, Rita De Michele, Katia Sparnacci, Aurora Cerasi, Sabrina Dominici, Luisa Tondelli, Giuseppe Altavilla, Ulrika Rolen, Riccardo Gavioli, Mauro Magnani, Michele Laus, and Egidio Brocca-Cofano
- Subjects
Vinyl alcohol ,Cell Survival ,Protein Conformation ,Fluorescent Antibody Technique ,Biocompatible Materials ,Styrene ,chemistry.chemical_compound ,Mice ,Protein structure ,Drug Delivery Systems ,Drug Stability ,Phagocytosis ,Animals ,Humans ,Methyl methacrylate ,Particle Size ,Polyacrylamide gel electrophoresis ,Cells, Cultured ,Dispersion polymerization ,AIDS Vaccines ,Mice, Inbred BALB C ,General Veterinary ,General Immunology and Microbiology ,Public Health, Environmental and Occupational Health ,Biological activity ,Flow Cytometry ,Combinatorial chemistry ,Immunohistochemistry ,In vitro ,Microspheres ,Infectious Diseases ,chemistry ,Biochemistry ,Gene Products, tat ,HIV-1 ,Microscopy, Electron, Scanning ,Molecular Medicine ,Electrophoresis, Polyacrylamide Gel ,Female ,tat Gene Products, Human Immunodeficiency Virus ,Oxidation-Reduction - Abstract
Two novel classes of biocompatible core-shell anionic microspheres, composed of an inner hard insoluble core, either made of poly(styrene) (PS) or poly(methyl methacrylate) (PMMA), and a soft outer tentacular shell made of long soluble negatively charged arms derived from the steric stabilizer, hemisuccinated poly(vinyl alcohol) or Eudragit L100/55, respectively, were prepared by dispersion polymerization and characterized. Five types of these novel microspheres, two made of poly(styrene) and hemisuccinated poly(vinyl alcohol) (A4 and A7), and three made of poly(methyl methacrylate) and Eudragit L100/55 (1D, 1E, H1D), differing for chemical composition, size, and surface charge density were analyzed for the delivery of the HIV-1 Tat protein for vaccine applications. All microspheres reversibly adsorbed the native biologically active HIV-1 Tat protein preventing Tat from oxidation and maintaining its biological activity, therefore increasing the shelf-life of the Tat protein vaccine. The microspheres efficiently delivered Tat intracellularly, and were not toxic in vitro nor in mice, even after multiple administrations. These results indicate that these novel microparticles are safe and represent a promising delivery system for vaccination with Tat, as well as for other subunit vaccines, particularly when a native protein conformation is required.
- Published
- 2003
49. Immunization with low doses of HIV-1 tat DNA delivered by novel cationic block copolymers induces CTL responses against Tat
- Author
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Antonella Caputo, Riccardo Gavioli, Chiara Boarini, Giuseppe Altavilla, Fabiola Micheletti, Franco Lorenzini, Arianna Castaldello, Luisa Tondelli, Monica Betti, Egidio Brocca-Cofano, Aurelio Cafaro, Michele Laus, Barbara Ensoli, and Katia Sparnacci
- Subjects
Cellular immunity ,Recombinant Fusion Proteins ,Biology ,HIV Antibodies ,Lymphocyte Activation ,Transfection ,Injections, Intramuscular ,DNA vaccination ,Polyethylene Glycols ,chemistry.chemical_compound ,Mice ,Antibody Specificity ,Cations ,Vaccines, DNA ,Cytotoxic T cell ,Animals ,Deoxyribonuclease I ,Enzyme Inhibitors ,AIDS Vaccines ,Drug Carriers ,Immunity, Cellular ,Mice, Inbred BALB C ,General Veterinary ,General Immunology and Microbiology ,Vaccination ,Public Health, Environmental and Occupational Health ,Fibroblasts ,biology.organism_classification ,Virology ,CTL ,Nylons ,Infectious Diseases ,chemistry ,Naked DNA ,Genes, tat ,Delayed-Action Preparations ,Lentivirus ,Gene Products, tat ,HIV-1 ,Molecular Medicine ,Methacrylates ,Female ,tat Gene Products, Human Immunodeficiency Virus ,DNA ,Spleen ,T-Lymphocytes, Cytotoxic - Abstract
Cytotoxic T cell responses are key to the control of intracellular pathogens including HIV-1. In particular, HIV-1 vaccines based on regulatory proteins, such as Tat, are aimed at controlling HIV-1 replication and at blocking disease development by inducing cytotoxic T cell responses. Naked DNA is capable of inducing such responses but it requires several inoculations of high amounts of DNA, and/or prime-boost regimens. Here, we show that a novel class of cationic block copolymers protect the DNA from DNAse I digestion, and improve DNA delivery to antigen-presenting cells (APCs) after intramuscular (i.m.) vaccination. In particular, three cationic block copolymers (K1, K2 and K5) were used to deliver the HIV-1 pCV-tat DNA vaccine in BALB/c mice. The results indicate that vaccination with a very low dose (1 microg) of pCV-tat delivered by the cationic block copolymer K2 is safe and, as compared to naked DNA (up to 30 microg), greatly increases the CTL response against Tat, which was detected in all animals in the absence or in the presence of re-stimulation.
- Published
- 2003
50. B cell subpopulations alteration in pathogenic and nonpathogenic SIV infections (VIR7P.1061)
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Egidio Brocca Cofano, Basile Siewe, Dave Kurt, Cui Ling Xu, Jan Kristoff, Dongzhu Ma, George Sebastian Haret-Richter, David Montefiore, Alan Landay, Ivona Pandrea, and Cristian Apetrei
- Subjects
Immunology ,Immunology and Allergy - Abstract
SIV/HIV infection is associated with B cell dysfunction, the significance of which is not known. We compared the B cell dynamics in blood, lymph nodes (LNs) and gut during SIVsab pathogenic infection of pigtailed macaques (PTMs) and nonprogressive SIVsab infection of African green monkeys (AGMs) by monitoring the B cell subsets, B regulatory cells (Bregs), CD4+ T follicular helper (Tfh) cells, B cell immune activation, apoptosis, exhaustion and homing to the intestine. Binding anti-gp41 and neutralizing antibodies (Nabs) were also measured. Acute SIV infection induced a transient but significant loss of total circulating B cells in PTMs only. In AGMs, total B cell from LNs increased during chronic infection. B cells transiently increased in the gut and naïve subset decreased in all three compartments in both species. Memory B cell subsets showed a different dynamic for both species. Bregs increased in PTM, correlated with IL-10 expression. B cell proliferation occurred in both species. PTMs expressed high baseline levels of α4β7, high degree of B cell activation and apoptosis and high frequency of Tfh. The dynamics of Ab response was similar in both species, but rapid progressor PTMs lacked the ability to mount anti-gp41. Our data show that B cell dysfunction only occurs in pathogenic SIV infection. While B cell changes were not correlated with production of Nabs, rapid disease progression associated a severe incapacity to mount an anti-SIV Ab response.
- Published
- 2014
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