226 results on '"Dittmer DP"'
Search Results
2. Viral infections associated with oral cancers and diseases in the context of HIV: a workshop report
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Speicher, DJ, primary, Ramirez-Amador, V, additional, Dittmer, DP, additional, Webster-Cyriaque, J, additional, Goodman, MT, additional, and Moscicki, A-B, additional
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- 2016
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3. The Oral HIV/AIDS Research Alliance Program: lessons learned and future directions.
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Shiboski, CH, Webster‐Cyriaque, JY, Ghannoum, M, Dittmer, DP, and Greenspan, JS
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ORAL disease diagnosis ,MEDICAL research ,DRUG therapy for AIDS ,ANTIRETROVIRAL agents ,AIDS-related opportunistic infections ,COLLECTION & preservation of biological specimens ,ORAL manifestations of general diseases ,CLINICAL trials ,CLINICAL pathology ,HIV infections ,RESEARCH methodology ,PAPILLOMAVIRUS diseases ,PRIORITY (Philosophy) ,RESEARCH evaluation ,THRUSH (Mouth disease) ,PREVENTION ,DIAGNOSIS ,SOCIETIES - Abstract
The Oral HIV/ AIDS Research Alliance ( OHARA) was established in 2006 to provide the capacity to investigate the oral complications associated with HIV/ AIDS within the ACTG infrastructure. Its goals were to explore the effects of potent antiretroviral therapy ( ART) on the development of opportunistic infections, and variation and resistance of opportunistic pathogens in the context of immune suppression and long-term ART. The objectives of this talk, presented as part of a plenary session at the 7th World Workshop on Oral Health and Disease in AIDS, were to (i) provide an overview of OHARA's most recent research agenda, and how it evolved since OHARA's inception; (ii) describe OHARA's main accomplishments, including examples of research protocols completed and their key findings; and (iii) describe spin-off projects derived from OHARA, lessons learned, and future directions. OHARA has met its central goal and made key contributions to the field in several ways: (i) by developing/updating diagnostic criteria for oral disease endpoints commonly measured in OHARA protocols and in HIV/ AIDS research in general and has creating standardized training modules, both for measuring these oral disease endpoints across clinical specialties, and for collecting oral fluid specimens; (ii) by implementing a total of nine protocols, six of which are completed. Three protocols involved domestic research sites, while three involved international research sites (in Africa, India, and South America); (iii) and by developing and validating a number of laboratory assays used in its protocols and in the field of oral HIV/ AIDS research. [ABSTRACT FROM AUTHOR]
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- 2016
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4. Exploring Kaposi's sarcoma-associated herpesvirus latent genes' role in viral lymphomagenesis using transgenic mice
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Sin, S-H, primary, Fakhari, FD, additional, and Dittmer, DP, additional
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- 2009
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5. Profiling of cellular and viral microRNAs in Kaposi sarcoma and viral-associated lymphoma
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Dittmer, DP, primary, O'Hara, AJ, additional, Wang, L, additional, Dezube, BJ, additional, Harrington, W, additional, and Damania, B, additional
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- 2009
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6. Interferon-γ production by neutrophils during bacterial pneumonia in mice.
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Yamada M, Gomez JC, Chugh PE, Lowell CA, Dinauer MC, Dittmer DP, Doerschuk CM, Yamada, Mitsuhiro, Gomez, John C, Chugh, Pauline E, Lowell, Clifford A, Dinauer, Mary C, Dittmer, Dirk P, and Doerschuk, Claire M
- Abstract
Rationale: Neutrophils are usually the first circulating leukocytes to respond during bacterial pneumonia. Their expression of oxidants, proteases, and other mediators present in granules is well documented, but their ability to produce mediators through transcription and translation after migration to an inflammatory site has been appreciated only more recently. Interferon (IFN)-γ is a cytokine with many functions important in host defense and immunity.Objectives: To examine the expression and function of IFN-γ in bacterial pneumonias.Methods: IFN-γ mRNA and protein were measured in digests of mouse lungs with 24-hour bacterial pneumonia. Bacterial clearance was studied with IFN-γ-deficient mice.Measurements and Main Results: Streptococcus pneumoniae and Staphylococcus aureus each induce expression of IFN-γ mRNA and protein by neutrophils by 24 hours. Only neutrophils that have migrated into pneumonic tissue produce IFN-γ. Deficiency of Hck/Fgr/Lyn, Rac2, or gp91(phox) prevents IFN-γ production. IFN-γ enhances bacterial clearance and is required for formation of neutrophil extracellular traps. In contrast, Pseudomonas aeruginosa and Escherichia coli induce production of IFN-γ mRNA but not protein. During pneumonia induced by E. coli but not S. pneumoniae, neutrophils produce microRNAs that target the 3' untranslated region of the IFN-γ gene.Conclusions: S. pneumoniae and S. aureus, but not P. aeruginosa and E. coli, induce emigrated neutrophils to produce IFN-γ within 24 hours. Hck/Fgr/Lyn, Rac2, and NADPH oxidase are required for IFN-γ production. IFN-γ facilitates bacterial clearance at least in part through regulating formation of neutrophil extracellular traps. Differential expression by neutrophils of microRNAs that target the 3' untranslated region of the IFN-γ gene may contribute to the pathogen-specific regulation of translation. [ABSTRACT FROM AUTHOR]- Published
- 2011
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7. Targeted therapy for Kaposi's sarcoma and Kaposi's sarcoma-associated herpesvirus.
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Dittmer DP, Krown SE, Dittmer, Dirk P, and Krown, Susan E
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- 2007
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8. AIDS related malignancies in Brazil.
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Sampaio J, Brites C, Araujo I, Bacchi CE, Dittmer DP, Tanaka PY, Harrington W Jr., Netto EM, Sampaio, Julio, Brites, Carlos, Araujo, Iguaracyra, Bacchi, Carlos E, Dittmer, Dirk P, Tanaka, Paula Y, Harrington, William Jr, and Netto, Eduardo M
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- 2007
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9. An Appraisal of Non-AIDS-Defining Cancers: Comment on 'Spectrum of Cancer Risk Late After AIDS Onset in the United States'.
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Dittmer DP
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- 2010
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10. More on HIV-associated Kaposi's sarcoma.
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Krown SE, Lee JY, Dittmer DP, AIDS Malignancy Consortium, Krown, Susan E, Lee, Jeannette Y, and Dittmer, Dirk P
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- 2008
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11. Is inflammation key in Kaposi sarcoma?
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Dittmer DP
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- Humans, Herpesvirus 8, Human, Sarcoma, Kaposi pathology, Sarcoma, Kaposi immunology, Inflammation pathology
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- 2024
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12. CD81 fusion alters SARS-CoV-2 Spike trafficking.
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Cone AS, Zhou Y, McNamara RP, Eason AB, Arias GF, Landis JT, Shifflett KW, Chambers MG, Yuan R, Willcox S, Griffith JD, and Dittmer DP
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- Animals, Humans, Mice, Antibodies, Viral immunology, Antibodies, Viral blood, COVID-19 virology, COVID-19 immunology, Extracellular Vesicles metabolism, Protein Transport, SARS-CoV-2 genetics, SARS-CoV-2 immunology, SARS-CoV-2 metabolism, Spike Glycoprotein, Coronavirus metabolism, Spike Glycoprotein, Coronavirus genetics, Tetraspanin 28 metabolism, Tetraspanin 28 genetics
- Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic caused the biggest public health crises in recent history. Many expect future coronavirus introductions into the human population. Hence, it is essential to understand the basic biology of these viruses. In natural infection, the SARS-CoV-2 Spike (S) glycoprotein is co-expressed with all other viral proteins, which modify cellular compartments to maximize virion assembly. By comparison, most of S is degraded when the protein is expressed in isolation, as in current molecular vaccines. To probe the maturation pathway of S, we redirected its maturation by fusing S to the tetraspanin protein CD81. CD81 is a defining constituent of extracellular vesicles (EVs) or exosomes. EVs are generated in large numbers by all cells, extruded into blood and lymph, and transfer cargo between cells and systemically (estimated 10
12 EVs per mL plasma). EVs, like platelets, can be transfused between unrelated donors. When fusing the proline-stabilized form of strain Delta S into the flexible, large extracellular loop of CD81 rather than being degraded in the lysosome, S was extruded into EVs. CD81-S fusion containing EVs were produced in large numbers and could be isolated to high purity. Purified CD81::S EVs bound ACE2, and S displayed on individual EV was observed by cryogenic electron microscopy (EM). The CD81::S-fusion EVs were non-toxic and elicited an anti-S trimer and anti-RBD antibody response in mice. This report shows a design path to maximize viral glycoprotein assembly and release without relying on the co-expression of potentially pathogenic nonstructural viral proteins., Importance: The severe acute respiratory syndrome coronavirus 2 pandemic caused the biggest public health crises in recent history. To understand the maturation pathway of S, we fused S to the tetraspanin protein CD81. The resulting molecule is secreted in extracellular vesicles and induces antibodies in mice. This may be a general design path for viral glycoprotein vaccines., Competing Interests: D.P.D., A.S.C., R.P.M., and Y.Z. declare competing interests with respect to the possible commercialization (WO 2024/ 073397) of some of the information presented. These are managed by the University of North Carolina. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or conflict with the subject matter or materials discussed in the paper apart from those disclosed.- Published
- 2024
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13. Cotargeting EBV lytic as well as latent cycle antigens increases T-cell potency against lymphoma.
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Sharma S, Mehta NU, Sauer T, Rollins LA, Dittmer DP, and Rooney CM
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- Humans, Animals, Mice, Epstein-Barr Virus Infections immunology, Epstein-Barr Virus Infections complications, Lymphoma immunology, Lymphoma therapy, Hodgkin Disease immunology, Hodgkin Disease therapy, Hodgkin Disease virology, Virus Latency, Herpesvirus 4, Human immunology, Antigens, Viral immunology, T-Lymphocytes immunology, T-Lymphocytes metabolism
- Abstract
Abstract: The remarkable efficacy of Epstein-Barr virus (EBV)-specific T cells for the treatment of posttransplant lymphomas has not been reproduced for EBV-positive (EBV+) malignancies outside the transplant setting. This is because of, in part, the heterogeneous expression and poor immunogenicity of the viral antigens expressed, namely latent membrane proteins 1 and 2, EBV nuclear antigen 1, and BamHI A rightward reading frame 1 (type-2 [T2] latency). However, EBV lytic cycle proteins are also expressed in certain EBV+ malignancies and, because several EBV lytic cycle proteins are abundantly expressed, have oncogenic activity, and likely contribute to malignancy, we sought and identified viral lytic-cycle transcripts in EBV+ Hodgkin lymphoma biopsies. This provided the rationale for broadening the target antigen-specific repertoire of EBV-specific T cells (EBVSTs) for therapy. We stimulated, peripheral blood mononuclear cells from healthy donors and patients with EBV+ lymphoma with both lytic and latent cycle proteins to produce broad repertoire (BR) EBVSTs. Compared with T2 antigen-specific EBVSTs, BR-EBVSTs more rapidly cleared autologous EBV+ tumors in NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ (NSG) mice and produced higher levels of proinflammatory cytokines that should reactivate the immunosuppressive tumor microenvironment leading to epitope spreading. Our results confirm that lytic cycle antigens are clinically relevant targets for EBV+ lymphoma and underpin the rationale for integrating BR-EBVSTs as a therapeutic approach for relapsed/refractory EBV+ lymphoma (www.clinicaltrials.gov identifiers: #NCT01555892 and #NCT04664179), as well as for other EBV-associated malignancies., (© 2024 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)
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- 2024
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14. The complete Kaposi sarcoma-associated herpesvirus genome induces early-onset, metastatic angiosarcoma in transgenic mice.
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Sin SH, Eason AB, Kim Y, Schneider JW, Damania B, and Dittmer DP
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- Animals, Mice, Genome, Viral, Humans, Antigens, Viral genetics, Nuclear Proteins genetics, Nuclear Proteins metabolism, Vascular Endothelial Growth Factor A metabolism, Vascular Endothelial Growth Factor A genetics, Ganciclovir therapeutic use, Ganciclovir pharmacology, Interleukin-10 genetics, Herpesvirus 8, Human genetics, Herpesvirus 8, Human pathogenicity, Mice, Transgenic, Hemangiosarcoma virology, Hemangiosarcoma genetics, Hemangiosarcoma pathology, Sarcoma, Kaposi virology, Sarcoma, Kaposi pathology, Disease Models, Animal
- Abstract
Kaposi sarcoma (KS) is the most common cancer in persons living with HIV. It is caused by KS-associated herpesvirus (KSHV). There exists no animal model for KS. Pronuclear injection of the 170,000-bp viral genome induces early-onset, aggressive angiosarcoma in transgenic mice. The tumors are histopathologically indistinguishable from human KS. As in human KS, all tumor cells express the viral latency-associated nuclear antigen (LANA). The tumors transcribe most viral genes, whereas endothelial cells in other organs only transcribe the viral latent genes. The tumor cells are of endothelial lineage and exhibit the same molecular pattern of pathway activation as KS, namely phosphatidylinositol 3-kinase (PI3K)/Akt/mTOR, interleukin-10 (IL-10), and vascular endothelial growth factor (VEGF). The KSHV-induced tumors are more aggressive than Ha-ras-induced angiosarcomas. Overall survival is increased by prophylactic ganciclovir. Thus, whole-virus KSHV-transgenic mice represent an accurate model for KS and open the door for the genetic dissection of KS pathogenesis and evaluation of therapies, including vaccines., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)
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- 2024
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15. Assessment of the safety of nivolumab in people living with HIV with advanced cancer on antiretroviral therapy: the AIDS Malignancy Consortium 095 Study.
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Rajdev L, Jackie Wang CC, Joshi H, Lensing S, Lee J, Ramos JC, Baiocchi R, Ratner L, Rubinstein PG, Ambinder R, Henry D, Streicher H, Little RF, Chiao E, Dittmer DP, Einstein MH, Cesarman E, Mitsuyasu R, and Sparano JA
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- Humans, Nivolumab adverse effects, CD4 Lymphocyte Count, Viral Load, Acquired Immunodeficiency Syndrome drug therapy, HIV Infections complications, HIV Infections drug therapy, Sarcoma, Kaposi drug therapy
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Background: Although immunotherapy has emerged as a therapeutic strategy for many cancers, there are limited studies establishing the safety and efficacy in people living with HIV (PLWH) and cancer., Methods: PLWH and solid tumors or Kaposi sarcoma (KS) receiving antiretroviral therapy and a suppressed HIV viral load received nivolumab at 3 mg/kg every 2 weeks, in two dose deescalation cohorts stratified by CD4 count (stratum 1: CD4 count > 200/µL and stratum 2: CD4 count 100-199/µL). An expansion cohort of 24 participants with a CD4 count > 200/µL was then enrolled., Results: A total of 36 PLWH received nivolumab, including 15 with KS and 21 with a variety of other solid tumors. None of the first 12 participants had dose-limiting toxicity in both CD4 strata, and five patients (14%) overall had grade 3 or higher immune related adverse events. Objective partial response occurred in nine PLWH and cancer (25%), including in six of 15 with KS (40%; 95% CI, 16.3-64.7). The median duration of response was 9.0 months overall and 12.5 months in KS. Responses were observed regardless of PDL1 expression. There were no significant changes in CD4 count or HIV viral load., Conclusions: Nivolumab has a safety profile in PLWH similar to HIV-negative subjects with cancer, and also efficacy in KS. Plasma HIV remained suppressed and CD4 counts remained stable during treatment and antiretroviral therapy, indicating no adverse impact on immune function., Trial Registration: ClinicalTrials.gov Identifier: NCT02408861., (© 2023 American Cancer Society.)
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- 2024
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16. A prospective cohort study identifies two types of HIV+ Kaposi Sarcoma lesions: proliferative and inflammatory.
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Moorad R, Kasonkanji E, Gumulira J, Gondwe Y, Dewey M, Pan Y, Peng A, Pluta LJ, Kudowa E, Nyasosela R, Tomoka T, Tweya H, Heller T, Gugsa S, Phiri S, Moore DT, Damania B, Painschab M, Hosseinipour MC, and Dittmer DP
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- Humans, HIV, Prospective Studies, Sarcoma, Kaposi complications, Sarcoma, Kaposi drug therapy, Sarcoma, Kaposi epidemiology, HIV Infections complications, HIV Infections drug therapy, HIV Infections epidemiology, Herpesvirus 8, Human physiology
- Abstract
Kaposi sarcoma (KS) is the most common cancer in people living with HIV (PLWH) in many countries where KS-associated herpesvirus is endemic. Treatment has changed little in 20 years, but the disease presentation has. This prospective cohort study enrolled 122 human immunodeficiency virus (HIV) positive KS patients between 2017 and 2019 in Malawi. Participants were treated with bleomycin, vincristine and combination antiretroviral therapy, the local standard of care. One-year overall survival was 61%, and progression-free survival was 58%. The 48-week complete response rate was 35%. RNAseq (n = 78) differentiated two types of KS lesions, those with marked endothelial characteristics and those enriched in inflammatory transcripts. This suggests that different KS lesions are in different disease states consistent with the known heterogeneous clinical response to treatment. In contrast to earlier cohorts, the plasma HIV viral load of KS patients in our study was highly variable. A total of 25% of participants had no detectable HIV; all had detectable KSHV viral load. Our study affirms that many KS cases today develop in PLWH with well-controlled HIV infection and that different KS lesions have differing molecular compositions. Further studies are needed to develop predictive biomarkers for this disease., (© 2023 UICC.)
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- 2023
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17. Pediatric HIV+ Kaposi sarcoma exhibits clinical, virological, and molecular features different from the adult disease.
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Caro-Vegas C, Peng A, Juarez A, Silverstein A, Kamiyango W, Villiera J, McAtee CL, Mzikamanda R, Tomoka T, Peckham-Gregory EC, Moorad R, Kovarik CL, Campbell LR, Mehta PS, Kazembe PN, Allen CE, Scheurer ME, Ozuah NW, Dittmer DP, and El-Mallawany NK
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- United States, Humans, Child, Adult, Cross-Sectional Studies, Virus Replication, Sarcoma, Kaposi, Herpesvirus 8, Human genetics, HIV Infections drug therapy
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BACKGROUNDKaposi sarcoma (KS) is among the most common childhood cancers in Eastern and Central Africa. Pediatric KS has a distinctive clinical presentation compared with adult KS, which includes a tendency for primary lymph node involvement, a considerable proportion of patients lacking cutaneous lesions, and a potential for fulminant disease. The molecular mechanisms or correlates for these disease features are unknown.METHODSThis was a cross-sectional study. All cases were confirmed by IHC for KS-associated herpesvirus (KSHV) LANA protein. Baseline blood samples were profiled for HIV and KSHV genome copy numbers by qPCR and secreted cytokines by ELISA. Biopsies were characterized for viral and human transcription, and KSHV genomes were determined when possible.RESULTSSeventy participants with pediatric KS were enrolled between June 2013 and August 2019 in Malawi and compared with adult patients with KS. They exhibited high KSHV genome copy numbers and IL-6/IL-10 levels. Four biopsies (16%) had a viral transcription pattern consistent with lytic viral replication.CONCLUSIONThe unique features of pediatric KS may contribute to the specific clinical manifestations and may direct future treatment options.FUNDINGUS National Institutes of Health U54-CA-254569, PO1-CA019014, U54-CA254564, RO1-CA23958.
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- 2023
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18. The Poisson distribution model fits UMI-based single-cell RNA-sequencing data.
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Pan Y, Landis JT, Moorad R, Wu D, Marron JS, and Dittmer DP
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- Sequence Analysis, RNA methods, Poisson Distribution, Cluster Analysis, Gene Expression Profiling methods, Single-Cell Analysis methods, RNA genetics
- Abstract
Background: Modeling of single cell RNA-sequencing (scRNA-seq) data remains challenging due to a high percentage of zeros and data heterogeneity, so improved modeling has strong potential to benefit many downstream data analyses. The existing zero-inflated or over-dispersed models are based on aggregations at either the gene or the cell level. However, they typically lose accuracy due to a too crude aggregation at those two levels., Results: We avoid the crude approximations entailed by such aggregation through proposing an independent Poisson distribution (IPD) particularly at each individual entry in the scRNA-seq data matrix. This approach naturally and intuitively models the large number of zeros as matrix entries with a very small Poisson parameter. The critical challenge of cell clustering is approached via a novel data representation as Departures from a simple homogeneous IPD (DIPD) to capture the per-gene-per-cell intrinsic heterogeneity generated by cell clusters. Our experiments using real data and crafted experiments show that using DIPD as a data representation for scRNA-seq data can uncover novel cell subtypes that are missed or can only be found by careful parameter tuning using conventional methods., Conclusions: This new method has multiple advantages, including (1) no need for prior feature selection or manual optimization of hyperparameters; (2) flexibility to combine with and improve upon other methods, such as Seurat. Another novel contribution is the use of crafted experiments as part of the validation of our newly developed DIPD-based clustering pipeline. This new clustering pipeline is implemented in the R (CRAN) package scpoisson., (© 2023. The Author(s).)
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- 2023
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19. Large-scale heparin-based bind-and-elute chromatography identifies two biologically distinct populations of extracellular vesicles.
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Zhou Y, Yuan R, Cone AS, Shifflett KW, Arias GF, Peng A, Chambers MG, McNamara RP, Willcox S, Landis JT, Pan Y, Griffith J, and Dittmer DP
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- Tandem Mass Spectrometry, Endothelial Cells, Chromatography, Affinity methods, Heparin pharmacology, Heparin analysis, Heparin chemistry, Extracellular Vesicles chemistry
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Purifying extracellular vesicles (EVs) has been challenging because EVs are heterogeneous in cargo yet share similar sizes and densities. Most surface marker-based affinity separation methods are limited to research or diagnostic scales. We report that heparin chromatography can separate purified EVs into two distinct subpopulations as ascertained by MS/MS: a non-heparin-binding (NHB) fraction that contains classical EV markers such as tetraspanins and a heparin-binding (HB) fraction enriched in fibronectins and histones. Both fractions were similarly fusogenic but induced different transcriptional responses in endothelial cells. While EVs that were purified by conventional, non-affinity methods alone induced ERK1/2 phosphorylation and Ki67, the NHB fraction did not. This result suggests heparin chromatography as an additional novel fractionation step that is inherently scalable, does not lead to loss of material, and separates inflammatory and pyrogenic EVs from unreactive EVs, which will improve clinical applications., (© 2023 The Authors. Journal of Extracellular Vesicles published by Wiley Periodicals, LLC on behalf of the International Society for Extracellular Vesicles.)
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- 2023
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20. Metatranscriptomics analysis reveals a novel transcriptional and translational landscape during Middle East respiratory syndrome coronavirus infection.
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Fritch EJ, Sanders W, Sims AC, Herring LE, Barker NK, Schepmoes AA, Weitz KK, Texier JR, Dittmer DP, Graves LM, Smith RD, Waters KM, Moorman NJ, Baric RS, and Graham RL
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Among all RNA viruses, coronavirus RNA transcription is the most complex and involves a process termed "discontinuous transcription" that results in the production of a set of 3'-nested, co-terminal genomic and subgenomic RNAs during infection. While the expression of the classic canonical set of subgenomic RNAs depends on the recognition of a 6- to 7-nt transcription regulatory core sequence (TRS), here, we use deep sequence and metagenomics analysis strategies and show that the coronavirus transcriptome is even more vast and more complex than previously appreciated and involves the production of leader-containing transcripts that have canonical and noncanonical leader-body junctions. Moreover, by ribosome protection and proteomics analyses, we show that both positive- and negative-sense transcripts are translationally active. The data support the hypothesis that the coronavirus proteome is much vaster than previously noted in the literature., Competing Interests: The authors declare no competing interests., (© 2023 The Author(s).)
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- 2023
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21. Today's Kaposi sarcoma is not the same as it was 40 years ago, or is it?
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Damania B and Dittmer DP
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- Humans, Viral Load, Sarcoma, Kaposi, Herpesvirus 8, Human
- Abstract
This review will provide an overview of the notion that Kaposi sarcoma (KS) is a disease that manifests under diverse and divergent circumstances. We begin with a historical introduction of KS and KS-associated herpesvirus (KSHV), highlight the diversity of clinical presentations of KS, summarize what we know about the cell of origin for this tumor, explore KSHV viral load as a potential biomarker for acute KSHV infections and KS-associated complications, and discuss immune modulators that impact KSHV infection, KSHV persistence, and KS disease., (© 2023 Wiley Periodicals LLC.)
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- 2023
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22. Comparative electrokinetic properties of extracellular vesicles produced by yeast and bacteria.
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Rogers NMK, McCumber AW, McMillan HM, McNamara RP, Dittmer DP, Kuehn MJ, Hendren CO, and Wiesner MR
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- Bacteria, Saccharomyces cerevisiae, Extracellular Vesicles chemistry
- Abstract
Extracellular vesicles (EVs) are nano-sized, biocolloidal proteoliposomes that have been shown to be produced by all cell types studied to date and are ubiquitous in the environment. Extensive literature on colloidal particles has demonstrated the implications of surface chemistry on transport behavior. Hence, one may anticipate that physicochemical properties of EVs, particularly surface charge-associated properties, may influence EV transport and specificity of interactions with surfaces. Here we compare the surface chemistry of EVs as expressed by zeta potential (calculated from electrophoretic mobility measurements). The zeta potentials of EVs produced by Pseudomonas fluorescens, Staphylococcus aureus, and Saccharomyces cerevisiae were largely unaffected by changes in ionic strength and electrolyte type, but were affected by changes in pH. The addition of humic acid altered the calculated zeta potential of the EVs, especially for those from S. cerevisiae. Differences in zeta potential were compared between EVs and their respective parent cell with no consistent trend emerging; however, significant differences were discovered between the different cell types and their EVs. These findings imply that, while EV surface charge (as estimated from zeta potential) is relatively insensitive to the evaluated environmental conditions, EVs from different organisms can differ regarding which conditions will cause colloidal instability., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)
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- 2023
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23. Intra-Host Evolution Provides for the Continuous Emergence of SARS-CoV-2 Variants.
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Landis JT, Moorad R, Pluta LJ, Caro-Vegas C, McNamara RP, Eason AB, Bailey A, Villamor FCS, Juarez A, Wong JP, Yang B, Broussard GS, Damania B, and Dittmer DP
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- Humans, Reinfection, Family, Mutation, Spike Glycoprotein, Coronavirus genetics, SARS-CoV-2 genetics, COVID-19
- Abstract
Variants of concern (VOC) in SARS-CoV-2 refer to viruses whose viral genomes differ from the ancestor virus by ≥3 single-nucleotide variants (SNVs) and that show the potential for higher transmissibility and/or worse clinical progression. VOC have the potential to disrupt ongoing public health measures and vaccine efforts. Still, too little is known regarding how frequently new viral variants emerge and under what circumstances. We report a study to determine the degree of SARS-CoV-2 sequence evolution in 94 patients and to estimate the frequency at which highly diverse variants emerge. Two cases accumulated ≥9 SNVs over a 2-week period and one case accumulated 23 SNVs over 3 weeks, including three nonsynonymous mutations in the spike protein (D138H, E554D, D614G). The remainder of the infected patients did not show signs of intra-host evolution. We estimate that in as much as 2% of hospitalized COVID-19 cases, variants with multiple mutations in the spike glycoprotein emerge in as little as 1 month of persistent intra-host virus replication. This suggests the continued local emergence of variants with multiple nonsynonymous SNVs, even in patients without overt immune deficiency. Surveillance by sequencing for (i) viremic COVID-19 patients, (ii) patients suspected of reinfection, and (iii) patients with diminished immune function may offer broad public health benefits. IMPORTANCE New SARS-CoV-2 variants can potentially disrupt ongoing public health measures and vaccine efforts. Still, little is known regarding how frequently new viral variants emerge and under what circumstances. Based on this study, we estimate that in hospitalized COVID-19 cases, variants with multiple mutations may emerge locally in as little as 1 month, even in patients without overt immune deficiency. Surveillance by sequencing for continuously shedding patients, patients suspected of reinfection, and patients with diminished immune function may offer broad public health benefits.
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- 2023
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24. Infant rhesus macaques immunized against SARS-CoV-2 are protected against heterologous virus challenge 1 year later.
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Milligan EC, Olstad K, Williams CA, Mallory M, Cano P, Cross KA, Munt JE, Garrido C, Lindesmith L, Watanabe J, Usachenko JL, Hopkins L, Immareddy R, Shaan Lakshmanappa Y, Elizaldi SR, Roh JW, Sammak RL, Pollard RE, Yee JL, Herbek S, Scobey T, Miehlke D, Fouda G, Ferrari G, Gao H, Shen X, Kozlowski PA, Montefiori D, Hudgens MG, Edwards DK, Carfi A, Corbett KS, Graham BS, Fox CB, Tomai M, Iyer SS, Baric R, Reader R, Dittmer DP, Van Rompay KKA, Permar SR, and De Paris K
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- Animals, Humans, Infant, SARS-CoV-2, COVID-19 Vaccines, Macaca mulatta, BNT162 Vaccine, Antibodies, Viral, Antibodies, Neutralizing, COVID-19, Viral Vaccines
- Abstract
The U.S. Food and Drug Administration only gave emergency use authorization of the BNT162b2 and mRNA-1273 SARS-CoV-2 vaccines for infants 6 months and older in June 2022. Yet questions regarding the durability of vaccine efficacy, especially against emerging variants, in this age group remain. We demonstrated previously that a two-dose regimen of stabilized prefusion Washington SARS-CoV-2 S-2P spike (S) protein encoded by mRNA encapsulated in lipid nanoparticles (mRNA-LNP) or purified S-2P mixed with 3M-052, a synthetic Toll-like receptor (TLR) 7/8 agonist, in a squalene emulsion (Protein+3M-052-SE) was safe and immunogenic in infant rhesus macaques. Here, we demonstrate that broadly neutralizing and spike-binding antibodies against variants of concern (VOCs), as well as T cell responses, persisted for 12 months. At 1 year, corresponding to human toddler age, we challenged vaccinated rhesus macaques and age-matched nonvaccinated controls intranasally and intratracheally with a high dose of heterologous SARS-CoV-2 B.1.617.2 (Delta). Seven of eight control rhesus macaques exhibited severe interstitial pneumonia and high virus replication in the upper and lower respiratory tract. In contrast, vaccinated rhesus macaques had faster viral clearance with mild to no pneumonia. Neutralizing and binding antibody responses to the B.1.617.2 variant at the day of challenge correlated with lung pathology and reduced virus replication. Overall, the Protein+3M-052-SE vaccine provided superior protection to the mRNA-LNP vaccine, emphasizing opportunities for optimization of current vaccine platforms. The observed efficacy of both vaccines 1 year after vaccination supports the implementation of an early-life SARS-CoV-2 vaccine.
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- 2023
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25. Genetic subgroups inform on pathobiology in adult and pediatric Burkitt lymphoma.
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Thomas N, Dreval K, Gerhard DS, Hilton LK, Abramson JS, Ambinder RF, Barta S, Bartlett NL, Bethony J, Bhatia K, Bowen J, Bryan AC, Cesarman E, Casper C, Chadburn A, Cruz M, Dittmer DP, Dyer MA, Farinha P, Gastier-Foster JM, Gerrie AS, Grande BM, Greiner T, Griner NB, Gross TG, Harris NL, Irvin JD, Jaffe ES, Henry D, Huppi R, Leal FE, Lee MS, Martin JP, Martin MR, Mbulaiteye SM, Mitsuyasu R, Morris V, Mullighan CG, Mungall AJ, Mungall K, Mutyaba I, Nokta M, Namirembe C, Noy A, Ogwang MD, Omoding A, Orem J, Ott G, Petrello H, Pittaluga S, Phelan JD, Ramos JC, Ratner L, Reynolds SJ, Rubinstein PG, Sissolak G, Slack G, Soudi S, Swerdlow SH, Traverse-Glehen A, Wilson WH, Wong J, Yarchoan R, ZenKlusen JC, Marra MA, Staudt LM, Scott DW, and Morin RD
- Subjects
- Child, Humans, Adult, Herpesvirus 4, Human, Mutation, Burkitt Lymphoma pathology, Epstein-Barr Virus Infections, Lymphoma, Large B-Cell, Diffuse pathology
- Abstract
Burkitt lymphoma (BL) accounts for most pediatric non-Hodgkin lymphomas, being less common but significantly more lethal when diagnosed in adults. Much of the knowledge of the genetics of BL thus far has originated from the study of pediatric BL (pBL), leaving its relationship to adult BL (aBL) and other adult lymphomas not fully explored. We sought to more thoroughly identify the somatic changes that underlie lymphomagenesis in aBL and any molecular features that associate with clinical disparities within and between pBL and aBL. Through comprehensive whole-genome sequencing of 230 BL and 295 diffuse large B-cell lymphoma (DLBCL) tumors, we identified additional significantly mutated genes, including more genetic features that associate with tumor Epstein-Barr virus status, and unraveled new distinct subgroupings within BL and DLBCL with 3 predominantly comprising BLs: DGG-BL (DDX3X, GNA13, and GNAI2), IC-BL (ID3 and CCND3), and Q53-BL (quiet TP53). Each BL subgroup is characterized by combinations of common driver and noncoding mutations caused by aberrant somatic hypermutation. The largest subgroups of BL cases, IC-BL and DGG-BL, are further characterized by distinct biological and gene expression differences. IC-BL and DGG-BL and their prototypical genetic features (ID3 and TP53) had significant associations with patient outcomes that were different among aBL and pBL cohorts. These findings highlight shared pathogenesis between aBL and pBL, and establish genetic subtypes within BL that serve to delineate tumors with distinct molecular features, providing a new framework for epidemiologic, diagnostic, and therapeutic strategies., (Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)
- Published
- 2023
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26. Barrier-to-autointegration factor 1 promotes gammaherpesvirus reactivation from latency.
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Broussard G, Ni G, Zhang Z, Li Q, Cano P, Dittmer DP, and Damania B
- Subjects
- Humans, Herpesvirus 4, Human genetics, Nucleotidyltransferases, Virus Latency genetics, Virus Replication, Epstein-Barr Virus Infections, Gammaherpesvirinae genetics, Herpesvirus 8, Human genetics
- Abstract
Gammaherpesviruses, including Kaposi sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV), are DNA viruses that are globally associated with human cancers and establish lifelong latency in the human population. Detection of gammaherpesviral infection by the cGAS-STING innate immune DNA-sensing pathway is critical for suppressing viral reactivation from latency, a process that promotes viral pathogenesis and transmission. We report that barrier-to-autointegration factor 1 (BAF)-mediated suppression of the cGAS-STING signaling pathway is necessary for reactivation of KSHV and EBV. We demonstrate a role for BAF in destabilizing cGAS expression and show that inhibiting BAF expression in latently infected, reactivating, or uninfected cells leads to increased type I interferon-mediated antiviral responses and decreased viral replication. Furthermore, BAF overexpression resulted in decreased cGAS expression at the protein level. These results establish BAF as a key regulator of the lifecycle of gammaherpesviruses and a potential target for treating viral infections and malignancies., (© 2023. The Author(s).)
- Published
- 2023
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27. Cardiovascular Disease and Thrombosis in HIV Infection.
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Perkins MV, Joseph SB, Dittmer DP, and Mackman N
- Subjects
- Humans, Aged, Inflammation complications, HIV Infections complications, HIV Infections diagnosis, HIV Infections drug therapy, Cardiovascular Diseases diagnosis, Cardiovascular Diseases epidemiology, Cardiovascular Diseases etiology, Thrombosis etiology, Thrombosis complications, Atherosclerosis epidemiology, Atherosclerosis complications
- Abstract
HIV infection has transitioned from an acute, fatal disease to a chronic one managed by antiretroviral therapy. Thus, the aging population of people living with HIV (PLWH) continues to expand. HIV infection results in a dysregulated immune system, wherein CD4
+ T cells are depleted, particularly in the gastrointestinal tract, disrupting the gut epithelial barrier. Long-term HIV infection is associated with chronic inflammation through potentially direct mechanisms caused by viral replication or exposure to viral proteins and indirect mechanisms resulting from increased translocation of microbial products from the intestine or exposure to antiretroviral therapy. Chronic inflammation (as marked by IL [interleukin]-6 and CRP [C-reactive protein]) in PLWH promotes endothelial cell dysfunction and atherosclerosis. PLWH show significantly increased rates of cardiovascular disease, such as myocardial infarction (risk ratio, 1.79 [95% CI, 1.54-2.08]) and stroke (risk ratio, 2.56 [95% CI, 1.43-4.61]). In addition, PLWH have increased levels of the coagulation biomarker D-dimer and have a two to ten-fold increased risk of venous thromboembolism compared with the general population. Several small clinical trials analyzed the effect of different antithrombotic agents on platelet activation, coagulation, inflammation, and immune cell activation. Although some markers for coagulation were reduced, most agents failed to reduce inflammatory markers in PLWH. More studies are needed to understand the underlying mechanisms driving inflammation in PLWH to create better therapies for lowering chronic inflammation in PLWH. Such therapies can potentially reduce atherosclerosis, cardiovascular disease, and thrombosis rates in PLWH and thus overall mortality in this population.- Published
- 2023
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28. Extracellular Vesicle Isolation by a Tangential-Flow Filtration-Based Large-Scale Purification Method.
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Yuan R, Zhou Y, Arias GF, and Dittmer DP
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- Filtration methods, Ultracentrifugation, Centrifugation, Culture Media, Conditioned metabolism, Chromatography, Gel, Extracellular Vesicles metabolism
- Abstract
Extracellular vesicle (EV) isolation from conditioned cell culture medium has been a challenging topic. It is particularly difficult to obtain pure and intact EVs at a large scale. The commonly used methods such as differential centrifugation, ultracentrifugation, size exclusion chromatography, polyethylene glycol (PEG) precipitation, filtration, and affinity-based purification each have their advantages and limitations. Here, we present a tangential-flow filtration (TFF) based, multi-step purification protocol that combines filtration, PEG precipitation, and Capto Core 700 multimodal chromatography (MMC) to isolate EVs at high purity from large volumes of cell culture conditioned medium. Inserting the TFF step before PEG precipitation removes proteins, which may aggregate in subsequent steps and co-purify with EVs., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2023
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29. Scaling Biosafety Up During and Down After the COVID-19 Pandemic.
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Dittmer DP, Eason AB, and Juarez A
- Abstract
Purpose: The aim of this work was to review and analyze changes to the practice of biosafety imposed by pandemics., Methods: A narrative review of the COVID-19 pandemic that began in 2020 and prior pandemics from the perspective of a working virologist., Results: By definition, pandemics, outbreaks, and other emergencies are transient phenomena. They manifest as waves of events that induce unforeseen needs and present unknown challenges. After a pandemic, the return to normality is as crucial as the scale-up during the exponential growth phase. The COVID-19 pandemic presents an example to study operational biosafety and biocontainment issues during community transmission of infectious agents with established pandemic potential, the propensity to induce severe disease, and the ability to disrupt aspects of human society., Conclusions: Scaling down heightened biocontainment measures after a pandemic is as important as scaling up during a pandemic. The availability of preventive vaccines, and therapeutic drug regimens, should be considered in risk assessments for laboratory studies. There exists the need to preserve situational memory at the personal and institutional levels that can be served by professional societies., Competing Interests: No competing financial interests exist., (Copyright 2022, ABSA International 2022.)
- Published
- 2022
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30. Mitochondrial protein, TBRG4, modulates KSHV and EBV reactivation from latency.
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Zhang H, Wong JP, Ni G, Cano P, Dittmer DP, and Damania B
- Subjects
- Humans, Reactive Oxygen Species metabolism, RNA-Binding Proteins metabolism, Herpesvirus 4, Human physiology, Herpesvirus 8, Human physiology, Mitochondrial Proteins metabolism, Virus Latency
- Abstract
Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr (EBV) are gammaherpesviruses associated with multiple human malignancies. KSHV is the etiological agent of Kaposi's Sarcoma, primary effusion lymphoma (PEL) and multicentric Castleman's disease (MCD). EBV is associated with Burkitt's lymphoma (BL), Hodgkin's lymphoma (HL), nasopharyngeal carcinoma (NPC) and gastric carcinoma (GC). KSHV and EBV establish life-long latency in the human host with intermittent periods of lytic reactivation. Here, we identified a cellular factor named transforming growth factor-beta regulator 4 (TBRG4) that plays a role in the gammaherpesvirus lifecycle. We find that TBRG4, a protein that is localized to the mitochondria, can regulate lytic reactivation from latency of both KSHV and EBV. Knockdown of TBRG4 in cells latently infected with KSHV or EBV induced viral lytic gene transcription and replication. TBRG4 deficiency causes mitochondrial stress and increases reactive oxygen species (ROS) production. Treatment with a ROS scavenger decreased viral reactivation from latency in TBRG4-depleted cells. These data suggest that TBRG4 serves as a cellular repressor of KSHV and EBV reactivation through the regulation of ROS production., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Zhang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2022
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31. AMC-070: Lenalidomide Is Safe and Effective in HIV-Associated Kaposi Sarcoma.
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Reid EG, Shimabukuro K, Moore P, Ambinder RF, Bui JD, Han S, Martínez-Maza O, Dittmer DP, Aboulafia D, Chiao EY, Maurer T, Baiocchi R, Mitsuyasu R, and Wachsman W
- Subjects
- Cytokines therapeutic use, Humans, Lenalidomide adverse effects, HIV Infections complications, HIV Infections drug therapy, Herpesvirus 8, Human, Sarcoma, Kaposi drug therapy, Sarcoma, Kaposi etiology, Sarcoma, Kaposi pathology
- Abstract
Purpose: Kaposi sarcoma (KS), an endothelial cell tumor associated with KS herpesvirus (KSHV), remains among the most common malignancies occurring with HIV infection (HIV-KS). As an oral anti-inflammatory, antiangiogenic, and immunomodulatory agent, lenalidomide is potentially an attractive alternative to standard chemotherapy for KS., Experimental Design: The primary objectives of this phase I/II trial were to determine the maximum tolerated dose (MTD) and response rates for lenalidomide in HIV-KS. Secondary objectives included correlating response with natural killer (NK) and T-cell subsets, plasma cytokines, viral copy number, and KSHV gene expression in biopsies. Four dose levels of oral lenalidomide taken 21 consecutive days of 28-day cycles were evaluated in adults with HIV-KS on antiretroviral therapy with controlled viremia., Results: Fifteen and 23 participants enrolled in phases I and II, respectively, 76% of whom had received prior KS therapy. The MTD was not reached, declaring 25 mg as the recommended phase II dose (RP2D). The most frequent adverse events were neutropenia, fatigue, leukopenia, and diarrhea. Of the 25 evaluable participants receiving RP2D, 60% responded. Correlative studies performed in a subset of participants demonstrated a significant increase in proportions of blood T cells with T-regulatory phenotype, and plasma cytokines trended toward a less inflammatory pattern. Clinical response was associated with loss of KSHV transcription., Conclusions: Lenalidomide is active in HIV-KS. The most common adverse events were manageable. With 60% of participants receiving RP2D obtaining a partial response and <10% discontinuing due to adverse events, the response and tolerability to lenalidomide support its use in HIV-KS. See related commentary by Henry and Maki, p. 2485., (©2022 American Association for Cancer Research.)
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- 2022
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32. Exosome-Encased Nucleic Acid Scaffold Chemotherapeutic Agents for Superior Anti-Tumor and Anti-Angiogenesis Activity.
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McNamara RP, Eason AB, Zhou Y, Bigi R, Griffith JD, Costantini LM, Rudek MA, Anders NM, Damania BA, and Dittmer DP
- Abstract
Extracellular vesicles (EVs), or exosomes, play a pivotal role in tumor growth and metastasis, such as in the case of Kaposi Sarcoma. By loading tumor-derived EVs with chemotherapeutic drugs, we noted that their pro-tumor/pro-angiogenic phenotype was converted into an anti-tumor phenotype in vivo . Drug concentration in EVs was significantly higher than in clinically approved liposome formulation, as retention was facilitated by the presence of miRNAs inside the natural EVs. This demonstrates a new mechanism by which to increase the payload capacity of nanoparticles. By exploiting the targeting preferences of tumor-derived EVs, chemotherapeutics can be directed to specifically poison the cells and the microenvironment that enables metastasis., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)
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- 2022
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33. Molecular profiling of breast and lung cancer in women with HIV reveals high tumor mutational burden.
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Caro-Vegas C, Ramirez C, Landis J, Adimora AA, Strickler H, French AL, Ofotokun I, Fischl M, Seaberg EC, Wang CJ, Spence AB, and Dittmer DP
- Subjects
- Biomarkers, Tumor, Female, High-Throughput Nucleotide Sequencing, Humans, Mutation, HIV Infections complications, Lung Neoplasms genetics
- Abstract
Objective: This study compared the mutation profile and tumor mutational burden (TMB) in women with HIV (WWH) diagnosed with lung adenocarcinoma (n = 8) or breast ductal neoplasm (n = 13) who were enrolled into the Women's Interagency HIV Study (WIHS)., Design: Previous studies tended to focus on single institutions based on sample availability. This study is based on a representative, multicenter cohort that represents the racial and ethnic composition of women with HIV in the United States., Methods: The study sequenced the complete human exome of n = 26 cancer samples from HIV-positive women, using Ion torrent next-generation sequencing. The study cohort was compared with a HIV-negative cohort obtained from the Genomic Data Commons Data Portal of the NCI., Results: There were no differences in known cancer mutations between breast cancer and lung cancer that developed in WWH and those that developed in HIV-negative (HIV-) women; however, WWH presented a significantly higher TMB in comparison to HIV- patients. Seventy-five percent of lung cancers and 61% of breast cancers were defined as TMB-high (more than 10 mutation/mb of DNA)., Conclusion: This study affirms the recommendation that WWH be included in clinical trials of novel treatments for these cancers. Although these data are preliminary, the high TMB in WLHV suggests, paradoxically, that this immune challenged population may benefit greatly from immune checkpoint inhibitor therapies., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)
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- 2022
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34. Imaging of surface microdomains on individual extracellular vesicles in 3-D.
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McNamara RP, Zhou Y, Eason AB, Landis JT, Chambers MG, Willcox S, Peterson TA, Schouest B, Maness NJ, MacLean AG, Costantini LM, Griffith JD, and Dittmer DP
- Subjects
- Biological Transport, Biomarkers analysis, Microscopy, Tetraspanins analysis, Extracellular Vesicles chemistry
- Abstract
Extracellular vesicles (EVs) are secreted from all cell types and are intimately involved in tissue homeostasis. They are being explored as vaccine and gene therapy platforms, as well as potential biomarkers. As their size is below the diffraction limit of light microscopy, direct visualizations have been daunting and single-particle studies under physiological conditions have been hampered. Here, direct stochastic optical reconstruction microscopy (dSTORM) was employed to visualize EVs in three-dimensions and to localize molecule clusters such as the tetraspanins CD81 and CD9 on the surface of individual EVs. These studies demonstrate the existence of membrane microdomains on EVs. These were confirmed by Cryo-EM. Individual particle visualization provided insights into the heterogeneity, structure, and complexity of EVs not previously appreciated., (© 2022 The Authors. Journal of Extracellular Vesicles published by Wiley Periodicals, LLC on behalf of the International Society for Extracellular Vesicles.)
- Published
- 2022
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35. Whole-genome sequencing of Kaposi sarcoma-associated herpesvirus (KSHV/HHV8) reveals evidence for two African lineages.
- Author
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Moorad R, Juarez A, Landis JT, Pluta LJ, Perkins M, Cheves A, and Dittmer DP
- Subjects
- Adult, Cell Line, Female, Gene Expression Regulation, Viral, Herpesviridae Infections diagnosis, Herpesvirus 8, Human isolation & purification, High-Throughput Nucleotide Sequencing, Humans, Male, Middle Aged, Phenotype, Phylogeny, Recombination, Genetic, Genome, Viral, Genomics methods, Genotype, Herpesviridae Infections virology, Herpesvirus 8, Human classification, Herpesvirus 8, Human genetics, Sarcoma, Kaposi virology
- Abstract
Kaposi sarcoma (KS)-associated herpesvirus (KSHV/HHV-8) was first sequenced from the body cavity (BC) lymphoma cell line, BC-1, in 1996. Few other KSHV genomes have been reported. Our knowledge of sequence variation for this virus remains spotty. This study reports additional genomes from historical US patient samples and from African KS biopsies. It describes an assay that spans regions of the virus that cannot be covered by short read sequencing. These include the terminal repeats, the LANA repeats, and the origins of replication. A phylogenetic analysis, based on 107 genomes, identified three distinct clades; one containing isolates from USA/Europe/Japan collected in the 1990s and two of Sub-Saharan Africa isolates collected since 2010. This analysis indicates that the KSHV strains circulating today differ from the isolates collected at the height of the AIDS epidemic. This analysis helps experimental designs and potential vaccine studies., (Copyright © 2022 Elsevier Inc. All rights reserved.)
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- 2022
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36. Evidence for Multiple Subpopulations of Herpesvirus-Latently Infected Cells.
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Landis JT, Tuck R, Pan Y, Mosso CN, Eason AB, Moorad R, Marron JS, and Dittmer DP
- Subjects
- Humans, Interleukin-6 metabolism, RNA, Messenger metabolism, Virus Latency, Gene Expression Regulation, Viral, Viral Proteins metabolism, Sarcoma, Kaposi, Lymphoma, Primary Effusion, Herpesvirus 8, Human genetics, Herpesviridae genetics, Herpesviridae metabolism
- Abstract
Kaposi's sarcoma-associated herpesvirus (KSHV)-associated primary effusion lymphomas (PEL) are traditionally viewed as homogenous regarding viral transcription and lineage of origin, but so far this contention has not been explored at the single-cell level. Single-cell RNA sequencing of latently infected PEL supports the existence of multiple subpopulations even within a single cell line. At most 1% of the cells showed evidence of near-complete lytic transcription. The majority of cells only expressed the canonical viral latent transcripts: those originating from the latency locus, the viral interferon regulatory factor locus, and the viral lncRNA nut-1/Pan/T1.1; however, a significant fraction of cells showed various degrees of more permissive transcription, and some showed no evidence of KSHV transcripts whatsoever. Levels of viral interleukin-6 (IL-6)/K2 mRNA emerged as the most distinguishing feature to subset KSHV-infected PEL. One newly uncovered phenotype is the existence of BCBL-1 cells that readily adhered to fibronectin and that displayed mesenchymal lineage-like characteristics. IMPORTANCE Latency is the defining characteristic of the Herpesviridae and central to the tumorigenesis phenotype of Kaposi's sarcoma-associated herpesvirus (KSHV). KSHV-driven primary effusion lymphomas (PEL) rapidly develop resistance to therapy, suggesting tumor instability and plasticity. At any given time, a fraction of PEL cells spontaneously reactivate KSHV, suggesting transcriptional heterogeneity even within a clonal cell line under optimal growth conditions. This study employed single-cell mRNA sequencing to explore the within-population variability of KSHV transcription and how it relates to host cell transcription. Individual clonal PEL cells exhibited differing patterns of viral transcription. Most cells showed the canonical pattern of KSHV latency (LANA, vCyc, vFLIP, Kaposin, and vIRFs), but a significant fraction evidenced extended viral gene transcription, including of the viral IL-6 homolog, open reading frame K2. This study suggests new targets of intervention for PEL. It establishes a conceptual framework to design KSHV cure studies analogous to those for HIV.
- Published
- 2022
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37. The ORF45 Protein of Kaposi Sarcoma-Associated Herpesvirus Is an Inhibitor of p53 Signaling during Viral Reactivation.
- Author
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Alzhanova D, Meyo JO, Juarez A, and Dittmer DP
- Subjects
- Castleman Disease, DNA-Binding Proteins metabolism, Gene Expression Regulation, Viral, Humans, Lymphoma, Primary Effusion virology, Sarcoma, Kaposi virology, Signal Transduction, Tumor Suppressor Protein p53 genetics, Ubiquitin-Specific Peptidase 7 genetics, Ubiquitin-Specific Peptidase 7 metabolism, Viral Proteins metabolism, Herpesvirus 8, Human genetics, Herpesvirus 8, Human physiology, Immediate-Early Proteins genetics, Immediate-Early Proteins metabolism, Open Reading Frames, Tumor Suppressor Protein p53 metabolism
- Abstract
Kaposi sarcoma-associated herpesvirus (KSHV) is a carcinogenic double-stranded DNA virus and the etiological agent of Kaposi sarcoma (KS), primary effusion lymphoma (PEL), and multicentric Castleman's disease (MCD). To prevent premature apoptosis and support its replication cycle, KSHV expresses a series of open reading frames (ORFs) that regulate signaling by the p53 tumor suppressor protein. Here, we describe a novel viral inhibitor of p53 encoded by KSHV ORF45 and identify its mechanism of action. ORF45 binds to p53 and prevents its interactions with USP7, a p53 deubiquitinase. This results in decreased p53 accumulation, localization of p53 to the cytoplasm, and diminished transcriptional activity. IMPORTANCE Unlike in other cancers, the tumor suppressor protein p53 is rarely mutated in Kaposi sarcoma (KS). Rather, Kaposi sarcoma-associated herpesvirus (KSHV) inactivates p53 through multiple viral proteins. One possible therapeutic approach to KS is the activation of p53, which would result in apoptosis and tumor regression. In this regard, it is important to understand all the mechanisms used by KSHV to modulate p53 signaling. This work describes a novel inhibitor of p53 signaling and a potential drug target, ORF45, and identifies the mechanisms of its action.
- Published
- 2021
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38. Impact of Anti-PD-1 and Anti-CTLA-4 on the Human Immunodeficiency Virus (HIV) Reservoir in People Living With HIV With Cancer on Antiretroviral Therapy: The AIDS Malignancy Consortium 095 Study.
- Author
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Rasmussen TA, Rajdev L, Rhodes A, Dantanarayana A, Tennakoon S, Chea S, Spelman T, Lensing S, Rutishauser R, Bakkour S, Busch M, Siliciano JD, Siliciano RF, Einstein MH, Dittmer DP, Chiao E, Deeks SG, Durand C, and Lewin SR
- Subjects
- CTLA-4 Antigen, Humans, Programmed Cell Death 1 Receptor, Virus Latency, Acquired Immunodeficiency Syndrome, HIV Infections complications, HIV Infections drug therapy, HIV-1, Neoplasms
- Abstract
Background: Antibodies to programmed cell death 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) may perturb human immunodeficiency virus (HIV) persistence during antiretroviral therapy (ART) by reversing HIV latency and/or boosting HIV-specific immunity, leading to clearance of infected cells. We tested this hypothesis in a clinical trial of anti-PD-1 alone or in combination with anti-CTLA-4 in people living with HIV (PLWH) and cancer., Methods: This was a substudy of the AIDS Malignancy Consortium 095 Study. ART-suppressed PLWH with advanced malignancies were assigned to nivolumab (anti-PD-1) with or without ipilimumab (anti-CTLA-4). In samples obtained preinfusion and 1 and 7 days after the first and fourth doses of immune checkpoint blockade (ICB), we quantified cell-associated unspliced (CA-US) HIV RNA and HIV DNA. Plasma HIV RNA was quantified during the first treatment cycle. Quantitative viral outgrowth assay (QVOA) to estimate the frequency of replication-competent HIV was performed before and after ICB for participants with samples available., Results: Of 40 participants, 33 received nivolumab and 7 nivolumab plus ipilimumab. Whereas CA-US HIV RNA did not change with nivolumab monotherapy, we detected a median 1.44-fold increase (interquartile range, 1.16-1.89) after the first dose of nivolumab and ipilimumab combination therapy (P = .031). There was no decrease in the frequency of cells containing replication-competent HIV, but in the 2 individuals on combination ICB for whom we had longitudinal QVOA, we detected decreases of 97% and 64% compared to baseline., Conclusions: Anti-PD-1 alone showed no effect on HIV latency or the latent HIV reservoir, but the combination of anti-PD-1 and anti-CTL-4 induced a modest increase in CA-US HIV RNA and may potentially eliminate cells containing replication-competent HIV., Clinical Trials Registration: NCT02408861., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)
- Published
- 2021
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39. Direct Stochastic Optical Reconstruction Microscopy of Extracellular Vesicles in Three Dimensions.
- Author
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Chambers MG, McNamara RP, and Dittmer DP
- Subjects
- Microscopy, Exosomes, Extracellular Vesicles
- Abstract
Extracellular vesicles (EVs) are released by all cell types and play an important role in cell signaling and homeostasis. The visualization of EVs often require indirect methods due to their small diameter (40-250 nm), which is beneath the diffraction limit of typical light microscopy. We have developed a super-resolution microscopy-based visualization of EVs to bypass the diffraction limit in both two and three dimensions. Using this approach, we can resolve the three-dimensional shape of EVs to within +/- 20 nm resolution on the XY-axis and +/- 50 nm resolution along the Z-axis. In conclusion, we propose that super-resolution microscopy be considered as a characterization method of EVs, including exosomes, as well as enveloped viruses.
- Published
- 2021
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40. Combined Inhibition of Akt and mTOR Is Effective Against Non-Hodgkin Lymphomas.
- Author
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Rivera-Soto R, Yu Y, Dittmer DP, and Damania B
- Abstract
Non-Hodgkin lymphoma (NHL) are a diverse group of hematological malignancies comprised of over 60 subtypes. These subtypes range from indolent to aggressive. The PI3K/Akt/mTOR pathway has been shown to contribute to cell survival and proliferation and is constitutively active in most NHL. MK-7075 (miransertib) and MK-4440 are small molecules that effectively inhibit Akt and have entered clinical development. Using in vitro and in vivo models of NHL, we explored targeting the kinase Akt with miransertib and MK-4440 alone or in combination with the mTORC1 inhibitor, rapamycin (sirolimus). Both Akt inhibitors inhibited the pathway and NHL proliferation in a subtype-dependent manner. However, these compounds had a minimal effect on the viability of primary B-cells. Importantly, the combination of miransertib and sirolimus synergistically reduced cell proliferation in NHL, including in one indolent subtype, e.g., follicular lymphoma (FL), and two aggressive subtypes, e.g., diffuse large B-cell lymphoma (DLBCL) and primary effusion lymphoma (PEL). To establish in vivo efficacy, we used several xenograft models of FL, DLBCL, and PEL. The results obtained in vivo were consistent with the in vitro studies. The FL xenograft was highly sensitive to the inhibition of Akt alone; however, the tumor burden of PEL xenografts was only significantly reduced when both Akt and mTORC1 were targeted. These data suggest that targeting the PI3K/Akt/mTOR pathway with Akt inhibitors such as miransertib in combination with mTOR inhibitors serves as a broadly applicable therapeutic in NHL., Competing Interests: YY worked for ArQule, Inc, now a wholly owned subsidiary of Merck & Co., Inc. BD served as an advisor to ArQule, Inc. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Rivera-Soto, Yu, Dittmer and Damania.)
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- 2021
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41. Novel modulators of p53-signaling encoded by unknown genes of emerging viruses.
- Author
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Alzhanova D, Corcoran K, Bailey AG, Long K, Taft-Benz S, Graham RL, Broussard GS, Heise M, Neumann G, Halfmann P, Kawaoka Y, Baric RS, Damania B, and Dittmer DP
- Subjects
- Chikungunya virus genetics, Chikungunya virus metabolism, Coronavirus genetics, Coronavirus metabolism, Ebolavirus genetics, Ebolavirus metabolism, Herpesvirus 8, Human genetics, Herpesvirus 8, Human metabolism, Humans, Influenza A virus genetics, Influenza A virus metabolism, Open Reading Frames, RNA Viruses genetics, Tumor Suppressor Protein p53 genetics, Viral Nonstructural Proteins metabolism, Zika Virus genetics, Zika Virus metabolism, Communicable Diseases, Emerging virology, RNA Viruses metabolism, Signal Transduction genetics, Tumor Suppressor Protein p53 metabolism
- Abstract
The p53 transcription factor plays a key role both in cancer and in the cell-intrinsic response to infections. The ORFEOME project hypothesized that novel p53-virus interactions reside in hitherto uncharacterized, unknown, or hypothetical open reading frames (orfs) of human viruses. Hence, 172 orfs of unknown function from the emerging viruses SARS-Coronavirus, MERS-Coronavirus, influenza, Ebola, Zika (ZIKV), Chikungunya and Kaposi Sarcoma-associated herpesvirus (KSHV) were de novo synthesized, validated and tested in a functional screen of p53 signaling. This screen revealed novel mechanisms of p53 virus interactions and two viral proteins KSHV orf10 and ZIKV NS2A binding to p53. Originally identified as the target of small DNA tumor viruses, these experiments reinforce the notion that all viruses, including RNA viruses, interfere with p53 functions. These results validate this resource for analogous systems biology approaches to identify functional properties of uncharacterized viral proteins, long non-coding RNAs and micro RNAs., Competing Interests: The authors have declared that no competing interests exist. Author Kathleen Corcoran was unable to confirm their authorship contributions. On their behalf, the corresponding author has reported their contributions to the best of their knowledge.
- Published
- 2021
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42. High-Density Amplicon Sequencing Identifies Community Spread and Ongoing Evolution of SARS-CoV-2 in the Southern United States.
- Author
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McNamara RP, Caro-Vegas C, Landis JT, Moorad R, Pluta LJ, Eason AB, Thompson C, Bailey A, Villamor FCS, Lange PT, Wong JP, Seltzer T, Seltzer J, Zhou Y, Vahrson W, Juarez A, Meyo JO, Calabre T, Broussard G, Rivera-Soto R, Chappell DL, Baric RS, Damania B, Miller MB, and Dittmer DP
- Subjects
- COVID-19, High-Throughput Nucleotide Sequencing, Humans, Pandemics, Phylogeny, SARS-CoV-2, United States, Betacoronavirus genetics, Coronavirus Infections epidemiology, Coronavirus Infections transmission, Pneumonia, Viral epidemiology, Pneumonia, Viral transmission, Spike Glycoprotein, Coronavirus genetics
- Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is constantly evolving. Prior studies focused on high-case-density locations, such as the northern and western metropolitan areas of the United States. This study demonstrates continued SARS-CoV-2 evolution in a suburban southern region of the United States by high-density amplicon sequencing of symptomatic cases. 57% of strains carry the spike D614G variant, which is associated with higher genome copy numbers, and its prevalence expands with time. Four strains carry a deletion in a predicted stem loop of the 3' UTR. The data are consistent with community spread within local populations and the larger continental United States. The data instill confidence in current testing sensitivity and validate "testing by sequencing" as an option to uncover cases, particularly nonstandard coronavirus disease 2019 (COVID-19) clinical presentations. This study contributes to the understanding of COVID-19 through an extensive set of genomes from a non-urban setting and informs vaccine design by defining D614G as a dominant and emergent SARS-CoV-2 isolate in the United States., Competing Interests: Declaration of Interests M.B.M. serves on the advisory boards for Curetis, Luminex Molecular Diagnostics, Cepheid, BioFire Diagnostics, and QIAGEN and as a consultant to Shield Diagnostics., (Copyright © 2020 The Author(s). Published by Elsevier Inc. All rights reserved.)
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- 2020
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43. Extracellular vesicles in virus infection and pathogenesis.
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McNamara RP and Dittmer DP
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- Biomarkers analysis, Chronic Disease, Extracellular Vesicles physiology, Humans, Signal Transduction, Virus Latency, Virus Replication, Extracellular Vesicles immunology, Extracellular Vesicles virology, Virus Diseases physiopathology, Viruses pathogenicity
- Abstract
Viruses are obligate intracellular parasites that usurp cellular signaling networks to promote pathogen spread and disease progression. Signaling through extracellular vesicles (EVs) is an emerging field of study in the virus-host interaction network. EVs relay information both locally and distally through incorporated contents, typically without tripping innate immune sensors. Therefore, this extracellular signaling axis presents itself as a tantalizing target for promoting a favorable niche for the pathogen(s) takeover of the host, particularly for chronic infections. From the incorporation of virus-encoded molecules such as micro RNAs and proteins/enzymes to the envelopment of entire infectious particles, evolutionary distinct viruses have shown a remarkable ability to converge on this means of communication. In this review, we will cover the recent advances in this field and explore how EV can be used as potential biomarkers for chronic, persistent, or latent virus infections., (Copyright © 2020 Elsevier B.V. All rights reserved.)
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- 2020
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44. SARS-CoV-2 Seroprevalence among a Southern U.S. Population Indicates Limited Asymptomatic Spread under Physical Distancing Measures.
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Barzin A, Schmitz JL, Rosin S, Sirpal R, Almond M, Robinette C, Wells S, Hudgens M, Olshan A, Deen S, Krejci P, Quackenbush E, Chronowski K, Cornaby C, Goins J, Butler L, Aucoin J, Boyer K, Faulk J, Alston-Johnson D, Page C, Zhou Y, Fiscus L, Damania B, Dittmer DP, and Peden DB
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- Antibodies, Viral blood, Betacoronavirus immunology, Betacoronavirus isolation & purification, COVID-19, Cohort Studies, Coronavirus Infections diagnosis, Coronavirus Infections epidemiology, Female, Humans, Male, Mandatory Programs, North Carolina epidemiology, Pneumonia, Viral diagnosis, Pneumonia, Viral epidemiology, SARS-CoV-2, Seroepidemiologic Studies, Asymptomatic Diseases epidemiology, Coronavirus Infections prevention & control, Coronavirus Infections transmission, Pandemics prevention & control, Pneumonia, Viral prevention & control, Pneumonia, Viral transmission
- Abstract
Characterizing the asymptomatic spread of SARS-CoV-2 is important for understanding the COVID-19 pandemic. This study was aimed at determining asymptomatic spread of SARS-CoV-2 in a suburban, Southern U.S. population during a period of state restrictions and physical distancing mandates. This is one of the first published seroprevalence studies from North Carolina and included multicenter, primary care, and emergency care facilities serving a low-density, suburban and rural population since description of the North Carolina state index case introducing the SARS-CoV-2 respiratory pathogen to this population. To estimate point seroprevalence of SARS-CoV-2 among asymptomatic individuals over time, two cohort studies were examined. The first cohort study, named ScreenNC, was comprised of outpatient clinics, and the second cohort study, named ScreenNC2, was comprised of inpatients unrelated to COVID-19. Asymptomatic infection by SARS-CoV-2 (with no clinical symptoms) was examined using an Emergency Use Authorization (EUA)-approved antibody test (Abbott) for the presence of SARS-CoV-2 IgG. This assay as performed under CLIA had a reported specificity/sensitivity of 100%/99.6%. ScreenNC identified 24 out of 2,973 (0.8%) positive individuals among asymptomatic participants accessing health care during 28 April to 19 June 2020, which was increasing over time. A separate cohort, ScreenNC2, sampled from 3 March to 4 June 2020, identified 10 out of 1,449 (0.7%) positive participants. IMPORTANCE This study suggests limited but accelerating asymptomatic spread of SARS-CoV-2. Asymptomatic infections, like symptomatic infections, disproportionately affected vulnerable communities in this population, and seroprevalence was higher in African American participants than in White participants. The low, overall prevalence may reflect the success of shelter-in-place mandates at the time this study was performed and of maintaining effective physical distancing practices among suburban populations. Under these public health measures and aggressive case finding, outbreak clusters did not spread into the general population., (Copyright © 2020 Barzin et al.)
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- 2020
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45. Modern Techniques for the Isolation of Extracellular Vesicles and Viruses.
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McNamara RP and Dittmer DP
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- Animals, Cell Communication, Exosomes, Extracellular Space physiology, Humans, Nanoparticles, Extracellular Vesicles chemistry, Viruses isolation & purification
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Extracellular signaling is pivotal to maintain organismal homeostasis. A quickly emerging field of interest within extracellular signaling is the study of extracellular vesicles (EV), which act as messaging vehicles for nucleic acids, proteins, metabolites, lipids, etc. from donor cells to recipient cells. This transfer of biologically active material within a vesicular body is similar to the infection of a cell through a virus particle, which transfers genetic material from one cell to another to preserve an infection state, and viruses are known to modulate EV. Although considerable heterogeneity exists within EV and viruses, this review focuses on those that are small (< 200 nm in diameter) and of relatively low density (< 1.3 g/mL). A multitude of isolation methods for EV and virus particles exist. In this review, we present an update on methods for their isolation, purification, and phenotypic characterization. We hope that the information we provide will be of use to basic science and clinical investigators, as well as biotechnologists in this emerging field. Graphical Abstract.
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- 2020
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46. Purification Methods and the Presence of RNA in Virus Particles and Extracellular Vesicles.
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Zhou Y, McNamara RP, and Dittmer DP
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- Exosomes metabolism, MicroRNAs metabolism, RNA, Messenger metabolism, RNA, Viral metabolism, Viruses genetics, Viruses metabolism, Extracellular Vesicles metabolism, RNA metabolism, Virion isolation & purification, Virion metabolism
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The fields of extracellular vesicles (EV) and virus infections are marred in a debate on whether a particular mRNA or non-coding RNA (i.e., miRNA) is packaged into a virus particle or copurifying EV and similarly, whether a particular mRNA or non-coding RNA is contained in meaningful numbers within an EV. Key in settling this debate, is whether the purification methods are adequate to separate virus particles, EV and contaminant soluble RNA and RNA:protein complexes. Differential centrifugation/ultracentrifugation and precipitating agents like polyethylene glycol are widely utilized for both EV and virus purifications. EV are known to co-sediment with virions and other particulates, such as defective interfering particles and protein aggregates. Here, we discuss how encased RNAs from a heterogeneous mixture of particles can be distinguished by different purification methods. This is particularly important for subsequent interpretation of whether the RNA associated phenotype is contributed solely by virus or EV particles or a mixture of both. We also discuss the discrepancy of miRNA abundance in EV from different input material.
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- 2020
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47. Early Progression and Immune Reconstitution Inflammatory Syndrome During Treatment of Mild-To-Moderate Kaposi Sarcoma in Sub-Saharan Africa and South America: Incidence, Long-Term Outcomes, and Effects of Early Chemotherapy.
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Nyirenda M, Ngongondo M, Kang M, Umbleja T, Krown SE, Godfrey C, Samaneka W, Mngqibisa R, Hoagland B, Mwelase N, Caruso S, Martinez-Maza O, Dittmer DP, Borok M, Hosseinipour MC, and Campbell TB
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- Adult, Africa South of the Sahara, Anti-HIV Agents therapeutic use, Antineoplastic Agents, Phytogenic therapeutic use, CD4 Lymphocyte Count, Disease Progression, Etoposide therapeutic use, Female, Humans, Immune Reconstitution Inflammatory Syndrome pathology, Male, Sarcoma, Kaposi pathology, South America, Treatment Outcome, Anti-HIV Agents adverse effects, Antiretroviral Therapy, Highly Active adverse effects, HIV Infections drug therapy, Immune Reconstitution Inflammatory Syndrome chemically induced, Sarcoma, Kaposi drug therapy
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Background: Early progression of AIDS-associated Kaposi sarcoma (KS-PD) and immune reconstitution inflammatory syndrome (KS-IRIS) sometimes occur after the initiation of antiretroviral therapy (ART)., Methods: Early KS-PD and KS-IRIS were assessed in the A5264/AMC-067 trial in which participants with mild-to-moderate AIDS-KS were randomized to initiate ART with either immediate or as-needed oral etoposide. Early KS-PD was defined as tumor progression within 12 weeks of ART initiation. When investigators had concern that early KS-PD was KS-IRIS, additional evaluations were performed. Suspected KS-IRIS was defined as early KS-PD accompanied by a CD4 count increase of ≥50 cells per cubic millimeter or plasma HIV-1 RNA decrease of ≥0.5 log10 copies/mL. Clinical outcome was a composite end point categorized as failure, stable, and response at 48 and 96 weeks compared with baseline., Results: Fifty of 190 participants had early KS-PD (27%): 28 had KS-IRIS and 22 were not evaluated for KS-IRIS. Early KS-PD and KS-IRIS incidences with immediate etoposide versus ART alone were 16% versus 39%, and 7% versus 21%, respectively. Week 48 clinical outcome was 45% failure, 18% stable, and 37% response for no early KS-PD; 82% failure, 2% stable, and 16% response for early KS-PD; and 88% failure, 0% stable, and 12% response for KS-IRIS. Cumulative incidence of KS tumor response by week 96 was 64% for no early KS-PD, 22% with early KS-PD, and 18% with KS-IRIS., Conclusions: Early KS-PD, including suspected KS-IRIS, was common after starting ART for AIDS-KS and was associated with worse long-term clinical outcomes. Starting ART concurrently with etoposide reduced the incidence of both early KS-PD and KS-IRIS compared with ART alone.
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- 2020
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48. Burden of respiratory viral infection in persons with human immunodeficiency virus.
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Sellers SA, Dover KL, Bailey AG, Cheves A, Eason AB, Popowitch EB, Miller MB, Wohl DA, Dittmer DP, and Fischer WA
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- Cost of Illness, Female, HIV genetics, Hospitalization statistics & numerical data, Humans, Male, Middle Aged, Pneumonia, Viral epidemiology, Prevalence, Prospective Studies, Respiratory Tract Infections complications, Tertiary Care Centers statistics & numerical data, Viruses classification, Viruses isolation & purification, Viruses pathogenicity, HIV Infections epidemiology, HIV Infections virology, High-Throughput Nucleotide Sequencing, Respiratory Tract Infections epidemiology, Respiratory Tract Infections virology, Viruses genetics
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This study was conducted to determine the prevalence of respiratory viral infections (RVI) in persons living with HIV (PLH) admitted with a respiratory complaint using real-time reverse transcription polymerase chain reaction and primer-independent next-generation sequencing (NGS). Of 82 subjects, respiratory viruses were the most common pathogen identified in 27 (33%), followed by fungus and bacteria in 8 (10%) and 4 (5%) subjects, respectively. Among subjects with RVI, 11 (41%) required ICU admission and 16 (59%) required mechanical ventilation. The proportion of respiratory viruses identified, and the associated complicated hospital course highlights the significant role that RVIs play in the lung health of PLH., (© 2020 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.)
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- 2020
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49. Pathogenesis of Aging and Age-related Comorbidities in People with HIV: Highlights from the HIV ACTION Workshop.
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Gabuzda D, Jamieson BD, Collman RG, Lederman MM, Burdo TH, Deeks SG, Dittmer DP, Fox HS, Funderburg NT, Pahwa SG, Pandrea I, Wilson CC, and Hunt PW
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People with HIV (PWH) experience accentuated biological aging, as defined by markers of inflammation, immune dysfunction, and the epigenetic clock. They also have an elevated risk of multiple age-associated comorbidities. To discuss current knowledge, research gaps, and priorities in aging and age-related comorbidities in treated HIV infection, the NIH program staff organized a workshop held in Bethesda, Maryland in September 2019. This review article describes highlights of discussions led by the Pathogenesis/Basic Science Research working group that focused on three high priority topics: immunopathogenesis; the microbiome/virome; and aging and senescence. We summarize knowledge in these fields and describe key questions for research on the pathogenesis of aging and age-related comorbidities in PWH. Understanding the drivers and mechanisms underlying accentuated biological aging is a high priority that will help identify potential therapeutic targets to improve healthspan in older PWH., Competing Interests: Nicholas Funderberg serves as a consultant for Gilead. Michael M. Lederman is the senior editor for Pathogens and Immunity. Steven G. Deeks, Dirk P. Dittmer, Nicholas T. Funderburg, and Peter W. Hunt serve as associate editors for Pathogens and Immunity., (© Pathogens and Immunity 2020.)
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- 2020
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50. Kaposi Sarcoma-Associated Herpesvirus Infection and Endemic Burkitt Lymphoma.
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Oluoch PO, Oduor CI, Forconi CS, Ong'echa JM, Münz C, Dittmer DP, Bailey JA, and Moormann AM
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- Adolescent, Age Factors, Burkitt Lymphoma epidemiology, Burkitt Lymphoma physiopathology, Child, Child, Preschool, Coinfection, Female, Herpesviridae Infections epidemiology, Herpesviridae Infections physiopathology, Humans, Infant, Kenya epidemiology, Male, Sarcoma, Kaposi epidemiology, Sarcoma, Kaposi physiopathology, Seroepidemiologic Studies, Burkitt Lymphoma etiology, Burkitt Lymphoma genetics, Herpesviridae genetics, Herpesviridae Infections etiology, Herpesviridae Infections genetics, Sarcoma, Kaposi complications, Sarcoma, Kaposi genetics
- Abstract
Background: Endemic Burkitt lymphoma (eBL) is associated with Epstein-Barr virus (EBV) and Plasmodium falciparum malaria coinfections. However, the role of Kaposi sarcoma-associated herpesvirus (KSHV), also endemic in Africa, has not been evaluated as a cofactor in eBL pathogenesis., Methods: Multiplexed seroprofiles for EBV, malaria, and KSHV were generated for 266 eBL patients, 78 non-eBL cancers, and 202 healthy children. KSHV and EBV loads were quantified by PCR., Results: KSHV seroprevalence did not differ by study group but was associated with age. Seropositivity, defined by K8.1/LANA or in combination with 5 other KSHV antigens (ORF59, ORF65, ORF61, ORF38, and K5) was associated with antimalarial antibody levels to AMA1 (odds ratio [OR], 2.41, P < .001; OR, 2.07, P < .001) and MSP1 (OR, 2.41, P = .0006; OR, 5.78, P < .001), respectively. KSHV loads did not correlate with antibody levels nor differ across groups but were significantly lower in children with detectable EBV viremia (P = .014)., Conclusions: Although KSHV-EBV dual infection does not increase eBL risk, EBV appears to suppress reactivation of KSHV while malaria exposure is associated with KSHV infection and/or reactivation. Both EBV and malaria should, therefore, be considered as potential effect modifiers for KSHV-associated cancers in sub-Saharan Africa., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)
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- 2020
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