331 results on '"A Gaggar"'
Search Results
2. Interferon-dependent signaling is critical for viral clearance in airway neutrophils
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Camilla Margaroli, Timothy Fram, Nirmal S. Sharma, Siddharth B. Patel, Jennifer Tipper, Sarah W. Robison, Derek W. Russell, Seth D. Fortmann, Mudassir M. Banday, Yixel Soto-Vazquez, Tarek Abdalla, Sawanan Saitornuang, Matthew C. Madison, Sixto M. Leal Jr., Kevin S. Harrod, Nathaniel B. Erdmann, and Amit Gaggar
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Immunology ,Medicine - Abstract
Neutrophilic inflammation characterizes several respiratory viral infections, including COVID-19–related acute respiratory distress syndrome, although its contribution to disease pathogenesis remains poorly understood. Blood and airway immune cells from 52 patients with severe COVID-19 were phenotyped by flow cytometry. Samples and clinical data were collected at 2 separate time points to assess changes during ICU stay. Blockade of type I interferon and interferon-induced protein with tetratricopeptide repeats 3 (IFIT3) signaling was performed in vitro to determine their contribution to viral clearance in A2 neutrophils. We identified 2 neutrophil subpopulations (A1 and A2) in the airway compartment, where loss of the A2 subset correlated with increased viral burden and reduced 30-day survival. A2 neutrophils exhibited a discrete antiviral response with an increased interferon signature. Blockade of type I interferon attenuated viral clearance in A2 neutrophils and downregulated IFIT3 and key catabolic genes, demonstrating direct antiviral neutrophil function. Knockdown of IFIT3 in A2 neutrophils led to loss of IRF3 phosphorylation, with consequent reduced viral catabolism, providing the first discrete mechanism to our knowledge of type I interferon signaling in neutrophils. The identification of this neutrophil phenotype and its association with severe COVID-19 outcomes emphasizes its likely importance in other respiratory viral infections and potential for new therapeutic approaches in viral illness.
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- 2023
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3. Longitudinal liver sampling in patients with chronic hepatitis B starting antiviral therapy reveals hepatotoxic CD8+ T cells
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Shirin Nkongolo, Deeqa Mahamed, Adrian Kuipery, Juan D. Sanchez Vasquez, Samuel C. Kim, Aman Mehrotra, Anjali Patel, Christine Hu, Ian McGilvray, Jordan J. Feld, Scott Fung, Diana Chen, Jeffrey J. Wallin, Anuj Gaggar, Harry L.A. Janssen, and Adam J. Gehring
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Immunology ,Infectious disease ,Medicine - Abstract
Accumulation of activated immune cells results in nonspecific hepatocyte killing in chronic hepatitis B (CHB), leading to fibrosis and cirrhosis. This study aims to understand the underlying mechanisms in humans and to define whether these are driven by widespread activation or a subpopulation of immune cells. We enrolled CHB patients with active liver damage to receive antiviral therapy and performed longitudinal liver sampling using fine-needle aspiration to investigate mechanisms of CHB pathogenesis in the human liver. Single-cell sequencing of total liver cells revealed a distinct liver-resident, polyclonal CD8+ T cell population that was enriched at baseline and displayed a highly activated immune signature during liver damage. Cytokine combinations, identified by in silico prediction of ligand-receptor interaction, induced the activated phenotype in healthy liver CD8+ T cells, resulting in nonspecific Fas ligand–mediated killing of target cells. These results define a CD8+ T cell population in the human liver that can drive pathogenesis and a key pathway involved in their function in CHB patients.
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- 2023
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4. Glycocalyx heparan sulfate cleavage promotes endothelial cell angiopoietin-2 expression by impairing shear stress–related AMPK/FoxO1 signaling
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Robert P. Richter, Amit R. Ashtekar, Lei Zheng, Danielle Pretorius, Tripathi Kaushlendra, Ralph D. Sanderson, Amit Gaggar, and Jillian R. Richter
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Vascular biology ,Medicine - Abstract
Angiopoietin-2 (Ang-2) is a key mediator of vascular disease during sepsis, and elevated plasma levels of Ang-2 are associated with organ injury scores and poor clinical outcomes. We have previously observed that biomarkers of endothelial glycocalyx (EG) damage correlate with plasma Ang-2 levels, suggesting a potential mechanistic linkage between EG injury and Ang-2 expression during states of systemic inflammation. However, the cell signaling mechanisms regulating Ang-2 expression following EG damage are unknown. In the current study, we determined the temporal associations between plasma heparan sulfate (HS) levels as a marker of EG erosion and plasma Ang-2 levels in children with sepsis and in mouse models of sepsis. Second, we evaluated the role of shear stress–mediated 5′-adenosine monophosphate–activated protein kinase (AMPK) signaling in Ang-2 expression following enzymatic HS cleavage from the surface of human primary lung microvascular endothelial cells (HLMVECs). We found that plasma HS levels peaked before plasma Ang-2 levels in children and mice with sepsis. Further, we discovered that impaired AMPK signaling contributed to increased Ang-2 expression following HS cleavage from flow-conditioned HLMVECs, establishing a paradigm by which Ang-2 may be upregulated during sepsis.
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- 2022
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5. An in vivo model for extracellular vesicle–induced emphysema
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Camilla Margaroli, Matthew C. Madison, Liliana Viera, Derek W. Russell, Amit Gaggar, Kristopher R. Genschmer, and J. Edwin Blalock
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Pulmonology ,Medicine - Abstract
Chronic obstructive pulmonary disease (COPD) is a debilitating chronic disease and the third-leading cause of mortality worldwide. It is characterized by airway neutrophilia, promoting tissue injury through release of toxic mediators and proteases. Recently, it has been shown that neutrophil-derived extracellular vesicles (EVs) from lungs of patients with COPD can cause a neutrophil elastase–dependent (NE-dependent) COPD-like disease upon transfer to mouse airways. However, in vivo preclinical models elucidating the impact of EVs on disease are lacking, delaying opportunities for therapeutic testing. Here, we developed an in vivo preclinical mouse model of lung EV–induced COPD. EVs from in vivo LPS-activated mouse neutrophils induced COPD-like disease in naive recipients through an α-1 antitrypsin–resistant, NE-dependent mechanism. Together, these results show a key pathogenic and mechanistic role for neutrophil-derived EVs in a mouse model of COPD. Broadly, the in vivo model described herein could be leveraged to develop targeted therapies for severe lung disease.
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- 2022
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6. HLA-C and KIR permutations influence chronic obstructive pulmonary disease risk
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Takudzwa Mkorombindo, Thi K. Tran-Nguyen, Kaiyu Yuan, Yingze Zhang, Jianmin Xue, Gerard J. Criner, Young-il Kim, Joseph M. Pilewski, Amit Gaggar, Michael H. Cho, Frank C. Sciurba, and Steven R. Duncan
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Immunology ,Pulmonology ,Medicine - Abstract
A role for hereditary influences in the susceptibility for chronic obstructive pulmonary disease (COPD) is widely recognized. Cytotoxic lymphocytes are implicated in COPD pathogenesis, and functions of these leukocytes are modulated by interactions between their killer cell Ig-like receptors (KIR) and human leukocyte antigen–Class I (HLA–Class I) molecules on target cells. We hypothesized HLA–Class I and KIR inheritance affect risks for COPD. HLA–Class I alleles and KIR genotypes were defined by candidate gene analyses in multiple cohorts of patients with COPD (total n = 392) and control smokers with normal spirometry (total n = 342). Compared with controls, patients with COPD had overrepresentations of HLA-C*07 and activating KIR2DS1, with underrepresentations of HLA-C*12. Particular HLA-KIR permutations were synergistic; e.g., the presence of HLA-C*07 + KIR2DS1 + HLA-C12null versus HLAC*07null + KIR2DS1null + HLA-C12 was associated with COPD, especially among HLA-C1 allotype homozygotes. Cytotoxicity of COPD lymphocytes was more enhanced by KIR stimulation than those of controls and was correlated with lung function. These data show HLA-C and KIR polymorphisms strongly influence COPD susceptibility and highlight the importance of lymphocyte-mediated cytotoxicity in COPD pathogenesis. Findings here also indicate that HLA-KIR typing could stratify at-risk patients and raise possibilities that HLA-KIR axis modulation may have therapeutic potential.
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- 2021
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7. Large-scale viral genome analysis identifies novel clinical associations between hepatitis B virus and chronically infected patients
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Ondrej Podlaha, Edward Gane, Maurizia Brunetto, Scott Fung, Wan-Long Chuang, Calvin Q. Pan, Zhaoshi Jiang, Yang Liu, Neeru Bhardwaj, Prasenjit Mukherjee, John Flaherty, Anuj Gaggar, Mani Subramanian, Namiki Izumi, Shalimar, Young-Suk Lim, Patrick Marcellin, Maria Buti, Henry L. Y. Chan, and Kosh Agarwal
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Medicine ,Science - Abstract
Abstract Despite the high global prevalence of chronic hepatitis B (CHB) infection, datasets covering the whole hepatitis B viral genome from large patient cohorts are lacking, greatly limiting our understanding of the viral genetic factors involved in this deadly disease. We performed deep sequencing of viral samples from patients chronically infected with HBV to investigate the association between viral genome variation and patients’ clinical characteristics. We discovered novel viral variants strongly associated with viral load and HBeAg status. Patients with viral variants C1817T and A1838G had viral loads nearly three orders of magnitude lower than patients without those variants. These patients consequently experienced earlier viral suppression while on treatment. Furthermore, we identified novel variants that either independently or in combination with precore mutation G1896A were associated with the transition from HBeAg positive to the negative phase of infection. These observations are consistent with the hypothesis that mutation of the HBeAg open reading frame is an important factor driving CHB patient’s HBeAg status. This analysis provides a detailed picture of HBV genetic variation in the largest patient cohort to date and highlights the diversity of plausible molecular mechanisms through which viral variation affects clinical phenotype.
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- 2019
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8. A mechanism for matrikine regulation in acute inflammatory lung injury
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Sarah W. Robison, JinDong Li, Liliana Viera, Jonathan P. Blackburn, Rakesh P. Patel, J. Edwin Blalock, Amit Gaggar, and Xin Xu
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COVID-19 ,Inflammation ,Medicine - Abstract
Proline-glycine-proline (PGP) and its acetylated form (Ac-PGP) are neutrophil chemoattractants generated by collagen degradation, and they have been shown to play a role in chronic inflammatory disease. However, the mechanism for matrikine regulation in acute inflammation has not been well established. Here, we show that these peptides are actively transported from the lung by the oligopeptide transporter, PEPT2. Following intratracheal instillation of Ac-PGP in a mouse model, there was a rapid decline in concentration of the labeled peptide in the bronchoalveolar lavage (BAL) over time and redistribution to extrapulmonary sites. In vitro knockdown of the PEPT2 transporter in airway epithelia or use of a competitive inhibitor of PEPT2, cefadroxil, significantly reduced uptake of Ac-PGP. Animals that received intratracheal Ac-PGP plus cefadroxil had higher levels of Ac-PGP in BAL and lung tissue. Utilizing an acute LPS-induced lung injury model, we demonstrate that PEPT2 blockade enhanced pulmonary Ac-PGP levels and lung inflammation. We further validated this effect using clinical samples from patients with acute lung injury in coculture with airway epithelia. This is the first study to our knowledge to determine the in vitro and in vivo significance of active matrikine transport as a mechanism of modulating acute inflammation and to demonstrate that it may serve as a potential therapeutic target.
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- 2021
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9. Prolyl endopeptidase contributes to early neutrophilic inflammation in acute myocardial transplant rejection
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Gregory A. Payne, Nirmal S. Sharma, Charitharth V. Lal, Chunyan Song, Lingling Guo, Camilla Margaroli, Liliana Viera, Siva Kumar, Jindong Li, Dongqi Xing, Melanie Bosley, Xin Xu, J. Michael Wells, James F. George, Jose Tallaj, Massoud Leesar, J. Edwin Blalock, and Amit Gaggar
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Cardiology ,Transplantation ,Medicine - Abstract
Altered inflammation and tissue remodeling are cardinal features of cardiovascular disease and cardiac transplant rejection. Neutrophils have increasingly been understood to play a critical role in acute rejection and early allograft failure; however, discrete mechanisms that drive this damage remain poorly understood. Herein, we demonstrate that early acute cardiac rejection increases allograft prolyl endopeptidase (PE) in association with de novo production of the neutrophil proinflammatory matrikine proline-glycine-proline (PGP). In a heterotopic murine heart transplant model, PGP production and PE activity were associated with early neutrophil allograft invasion and allograft failure. Pharmacologic inhibition of PE with Z-Pro-prolinal reduced PGP, attenuated early neutrophil graft invasion, and reduced proinflammatory cytokine expression. Importantly, these changes helped preserve allograft rejection-free survival and function. Notably, within 2 independent patient cohorts, both PGP and PE activity were increased among patients with biopsy-proven rejection. The observed induction of PE and matrikine generation provide a link between neutrophilic inflammation and cardiovascular injury, represent a potential target to reduce allogenic immune responses, and uncover a mechanism of cardiovascular disease that has been previously unrecognized to our knowledge.
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- 2021
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10. Antiviral kinetics of tenofovir alafenamide and tenofovir disoproxil fumarate over 24 weeks in women of childbearing potential with chronic HBV.
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Calvin Q Pan, Ting-Tsung Chang, Si Hyun Bae, Maurizia Brunetto, Wai-Kay Seto, Carla S Coffin, Susanna K Tan, Shuyuan Mo, John F Flaherty, Anuj Gaggar, Mindie H Nguyen, Mustafa Kemal Çelen, Alexander Thompson, and Edward J Gane
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Medicine ,Science - Abstract
Background/purposeUse of tenofovir disoproxil fumarate (TDF) improves patient outcomes in preventing mother-to-child transmission (pMTCT) of the hepatitis B virus (HBV) in mothers with chronic HBV and high viral loads. Given the lack of data for tenofovir alafenamide (TAF) in pMTCT, rates of early viral suppression with TAF and TDF were evaluated in women of childbearing potential (WOCBP) participating in 2 randomized, double-blind, Phase 3 studies in chronic HBV.MethodsIn a patient subset meeting WOCBP criteria and with baseline HBV DNA >200,000 IU/mL, rates of viral suppression with TAF or TDF in achieving the target of HBV DNA ResultsIn 275 of 1298 (21%) patients meeting WOCBP criteria with high viral load, 93% and 96% had HBV DNA ConclusionsIn WOCBP with high VL, no differences were found between TAF and TDF in reducing HBV DNA to levels associated with lower transmission risk. These data support ongoing studies of TAF for pMTCT.
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- 2021
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11. Haemophilus influenzae persists in biofilm communities in a smoke-exposed ferret model of COPD
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Benjamin C. Hunt, Denise Stanford, Xin Xu, Jindong Li, Amit Gaggar, Steven M. Rowe, S. Vamsee Raju, and W. Edward Swords
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Medicine - Abstract
Rationale Non-typeable Haemophilus influenzae (NTHi) is a common inhabitant of the human nasopharynx and upper airways that can cause opportunistic infections of the airway mucosa including bronchopulmonary infections in patients with chronic obstructive pulmonary disease (COPD). It is clear that opportunistic infections contribute significantly to inflammatory exacerbations of COPD; however, there remains much to be learned regarding specific host and microbial determinants of persistence and/or clearance in this context. Methods In this study, we used a recently described ferret model for COPD, in which animals undergo chronic long-term exposure to cigarette smoke, to define host–pathogen interactions during COPD-related NTHi infections. Results NTHi bacteria colonised the lungs of smoke-exposed animals to a greater extent than controls, and elicited acute host inflammation and neutrophilic influx and activation, along with a significant increase in airway resistance and a decrease in inspiratory capacity consistent with inflammatory exacerbation; notably, these findings were not observed in air-exposed control animals. NTHi bacteria persisted within multicellular biofilm communities within the airway lumen, as evidenced by immunofluorescent detection of bacterial aggregates encased within a sialylated matrix as is typical of NTHi biofilms and differential bacterial gene expression consistent with the biofilm mode of growth. Conclusions Based on these results, we conclude that acute infection with NTHi initiates inflammatory exacerbation of COPD disease. The data also support the widely held hypothesis that NTHi bacteria persist within multicellular biofilm communities in the lungs of patients with COPD.
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- 2020
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12. The Matrikine Acetylated Proline-Glycine-Proline Couples Vascular Inflammation and Acute Cardiac Rejection
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Gregory A. Payne, Jindong Li, Xin Xu, Patricia Jackson, Hongwei Qin, David M. Pollock, J. Michael Wells, Suzanne Oparil, Massoud Leesar, Rakesh P. Patel, J. Edwin Blalock, and Amit Gaggar
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Medicine ,Science - Abstract
Abstract The extracellular matrix (ECM) is a dynamic, bioactive structure critical to organ development, structure and function. Excessive remodeling of the ECM is a hallmark of a variety of inflammatory conditions including vascular disease. Endothelin-1 (ET1) synthesis is understood to promote cardiovascular diseases including acute cardiac transplant rejection; however, the contribution of ECM-derived chemokines (matrikines) to vascular inflammation remains poorly understood. Herein we report that the matrikine acetylated Pro-Gly-Pro (PGP) stimulates vascular inflammation through activation of endothelial CXC Chemokine Receptor 2 (CXCR2) and production of endothelin-1 both in vitro and in vivo. As a proof of hypothesis, we demonstrate that coronary PGP levels associate with both circulating endothelin-1 and acute rejection in cardiac transplant patients (sensitivity of 100% and specificity of 86%). These findings establish PGP as a novel mediator in cardiovascular disease, and implicate bioactive matrix fragments as underappreciated agents potentially active in numerous conditions propagated by progressive vascular inflammation.
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- 2017
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13. Genomic modeling of hepatitis B virus integration frequency in the human genome.
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Ondrej Podlaha, George Wu, Bryan Downie, Raghuraman Ramamurthy, Anuj Gaggar, Mani Subramanian, Zhishen Ye, and Zhaoshi Jiang
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Medicine ,Science - Abstract
Hepatitis B infection is a world-wide public health burden causing serious liver complications. Previous studies suggest that hepatitis B integration into the human genome plays a crucial role in triggering oncogenic process and may also constitutively produce viral antigens. Despite the progress in HBV biology and sequencing technology, our fundamental understanding of how many hepatocytes in the liver actually carry viral integrations is still lacking. Herein we provide evidence that the HBV virus integrates with a lower-bound frequency of 0.84 per diploid genome in hepatitis B positive hepatocellular cancer patients. Moreover, we calculate that integrated viral DNA generates ~80% of the HBsAg transcripts in these patients. These results underscore the need to re-evaluate the clinical end-point and treatment strategies for chronic hepatitis B patients.
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- 2019
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14. Hepatitis B Surface Antigen Levels Can Be Used to Rule Out Cirrhosis in Hepatitis B e Antigen-Positive Chronic Hepatitis B
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Milan J. Sonneveld, Maria Buti, R.A. de Man, Rong-Nan Chien, R.J. de Knegt, Qing Xie, Bettina E. Hansen, Anuj Gaggar, Teerha Piratvisuth, Harry L.A. Janssen, Vedran Pavlovic, Stefan Zeuzem, H.L. Chan, Jidong Jia, Willem P. Brouwer, Cynthia Wat, and Gastroenterology & Hepatology
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0301 basic medicine ,Liver Cirrhosis ,medicine.medical_specialty ,HBsAg ,Hepatitis B virus ,Cirrhosis ,Gastroenterology ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,Hepatitis B, Chronic ,Randomized controlled trial ,SDG 3 - Good Health and Well-being ,Fibrosis ,law ,Internal medicine ,medicine ,Immunology and Allergy ,Humans ,Hepatitis B e Antigens ,Hepatitis B Surface Antigens ,business.industry ,Odds ratio ,Hepatitis B ,Hepatology ,medicine.disease ,030104 developmental biology ,Infectious Diseases ,DNA, Viral ,030211 gastroenterology & hepatology ,Hepatic fibrosis ,business - Abstract
Background Serum hepatitis B surface antigen (HBsAg) levels correlate with the duration of chronic hepatitis B virus (HBV) infection and may predict the extent of hepatic fibrosis. Methods We analyzed data from the SONIC-B database, which contains data from 8 global randomized trials and 2 large hepatology centers. Relationship between HBsAg levels and presence of significant fibrosis (Ishak 3–4) or cirrhosis (Ishak 5–6) were explored, and clinically relevant cutoffs were identified to rule out cirrhosis. Results The dataset included 2779 patients: 1866 hepatitis B e antigen (HBeAg)-positive; 322 with cirrhosis. Among HBeAg-positive patients, lower HBsAg levels were associated with higher rates of significant fibrosis (odds ratio [OR], 0.419; P < .001) and cirrhosis (OR, 0.435; P < .001). No relationship was observed among HBeAg-negative patients. Among HBeAg-positive patients, genotype-specific HBsAg cutoffs had excellent negative predictive values (>97%) and low misclassification rates (≤7.1%) and may therefore have utility in ruling out cirrhosis. Diagnostic performance of the HBsAg cutoffs was comparable among patients in whom cirrhosis could not be ruled out with fibrosis 4 (FIB-4). Conclusions Hepatitis B virus genotype-specific HBsAg cutoffs may have utility in ruling out presence of cirrhosis in HBeAg-positive patients with genotypes B, C, and D and can be an adjunct to FIB-4 to reduce the need for further testing.
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- 2022
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15. Natural Killer Cells in Cancer and Cancer Immunotherapy
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Ismail Gögenur, Hans Raskov, Shruti Gaggar, Adile Orhan, and Ali Salanti
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Cancer Research ,Adoptive cell transfer ,Receptors, Chimeric Antigen ,Innate immune system ,business.industry ,medicine.medical_treatment ,Cancer ,Immunotherapy ,CD8-Positive T-Lymphocytes ,medicine.disease ,Immunotherapy, Adoptive ,Chimeric antigen receptor ,Killer Cells, Natural ,Immune system ,Oncology ,Cancer immunotherapy ,Neoplasms ,medicine ,Cancer research ,Humans ,business ,CD8 - Abstract
The detection and killing of neoplastic cells require coordination of a variety of antitumor effector cells. Natural killer (NK) cells of the innate immune system are at the forefront of the body's defense systems and evidence suggests that the infiltration and cytotoxicity of NK cells in the cancer tissue influence treatment efficacy and survival. As powerful effectors in the anticancer immune response, NK cells rapidly recognize and kill transformed cells with little reactivity against healthy self-tissues, which highlights their potential role in cancer immunotherapy. Modern immunotherapeutic approaches include immune checkpoint inhibitors to revitalize dysfunctional T cells and adoptive cell transfer using CD8+ T cells with chimeric antigen receptors to enhance their functionality. However, treatment responses may be short-lived and risk of discontinuation due to adverse effects necessitates the development of safer immuno-oncologic therapies with improved outcomes. To this end, novel combinatorial interventions using T cells and NK cells and strategies for overcoming associated challenges are currently being investigated. This review summarizes the advances in the research on NK cells in cancer and cancer immunotherapy and discusses the possible implications for future cancer treatment.
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- 2021
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16. Safety, Pharmacokinetics, and Pharmacodynamics of the Oral TLR8 Agonist Selgantolimod in Chronic Hepatitis B
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Circe McDonald, Jeffrey J. Wallin, Anh Hoa Nguyen, Diana Y. Chen, Edward Gane, Priyanka Arora, Kumar Visvanathan, Hyung Joon Kim, Young-Suk Lim, Susanna K. Tan, Anuj Gaggar, Yoon Jun Kim, and Stuart K. Roberts
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Adult ,Male ,0301 basic medicine ,Agonist ,medicine.medical_specialty ,Sustained Virologic Response ,Nausea ,medicine.drug_class ,medicine.disease_cause ,Placebo ,Antiviral Agents ,Dizziness ,Gastroenterology ,03 medical and health sciences ,Hepatitis B, Chronic ,0302 clinical medicine ,Pharmacokinetics ,Internal medicine ,medicine ,Clinical endpoint ,Humans ,Adverse effect ,Hepatitis B virus ,Dose-Response Relationship, Drug ,Hepatology ,Interleukin-12 Subunit p40 ,business.industry ,Headache ,Middle Aged ,Interleukin 1 Receptor Antagonist Protein ,Pyrimidines ,030104 developmental biology ,Toll-Like Receptor 8 ,Pharmacodynamics ,Female ,030211 gastroenterology & hepatology ,medicine.symptom ,Hexanols ,business - Abstract
Background and aims In patients with chronic hepatitis B (CHB) infection, activation of toll-like receptor 8 may induce antiviral immunity and drive functional cure. Selgantolimod, a toll-like receptor 8 agonist, was evaluated in patients with CHB who were virally suppressed on oral antiviral treatment or viremic and not on oral antiviral treatment. Approach and results In this phase 1b study, patients were randomized 4:1 to receive either selgantolimod or placebo once weekly. Virally suppressed patients received either 1.5 mg (for 2 weeks) or 3 mg (for 2 weeks or 4 weeks). Viremic patients received 3 mg for 2 weeks. The primary endpoint was safety, as assessed by adverse events (AEs), laboratory abnormalities, and vital sign examination. Pharmacokinetic and pharmacodynamic parameters were assessed by plasma analysis. A total of 38 patients (28 virally suppressed, 10 viremic) were enrolled from six sites in Australia, New Zealand, and South Korea. Twenty patients (53%) experienced an AE and 32 (84%) had laboratory abnormalities, all of which were mild or moderate in severity. The most common AEs were headache (32%), nausea (24%), and dizziness (13%). With a half-life of 5 hours, no accumulation of selgantolimod was observed with multiple dosing. Selgantolimod induced transient dose-dependent increases in serum cytokines, including IL-12p40 and IL-1RA, which are important for the expansion and activity of multiple T- cell subsets and innate immunity. Conclusion Selgantolimod was safe and well-tolerated in virally suppressed and viremic patients with CHB and elicited cytokine responses consistent with target engagement. Further studies with longer durations of selgantolimod treatment are required to evaluate efficacy.
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- 2021
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17. Hepatitis B virus genome diversity in adolescents: Tenofovir disoproxil fumarate treatment effect and HBeAg serocon version
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Christophe Combet, Charlotte Hedskog, Neeru Bhardwaj, Fabien Zoulim, Evguenia S. Svarovskaia, Ondrej Podlaha, Karen F. Murray, Hongmei Mo, Anuj Gaggar, Centre de Recherche en Cancérologie de Lyon (UNICANCER/CRCL), Centre Léon Bérard [Lyon]-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
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Hepatitis B virus ,Adolescent ,Tenofovir ,[SDV]Life Sciences [q-bio] ,Population ,medicine.disease_cause ,Placebo ,Antiviral Agents ,Genome ,Nucleotide diversity ,03 medical and health sciences ,Basal (phylogenetics) ,Hepatitis B, Chronic ,0302 clinical medicine ,Virology ,medicine ,Humans ,Hepatitis B e Antigens ,030212 general & internal medicine ,Seroconversion ,education ,ComputingMilieux_MISCELLANEOUS ,education.field_of_study ,Hepatology ,business.industry ,Viral Load ,3. Good health ,Treatment Outcome ,Infectious Diseases ,DNA, Viral ,030211 gastroenterology & hepatology ,business ,human activities ,medicine.drug - Abstract
More systematic analysis of hepatitis B virus (HBV) genome diversity, linked with tenofovir disoproxil fumarate (TDF) treatment and HBeAg seroconversion, are needed. GS-US-174-0115 was a double-blind, placebo-controlled, Phase 3, 192-week clinical trial that evaluated TDF in adolescents with chronic hepatitis B (CHB). HBV full-genome deep sequencing was performed using Illumina MiSeq at baseline (BL; n = 85), Week 8 (W8; n = 80), Week 72 (W72; PBO only, n = 42), and treatment-free follow-up (TDF only, n = 25). The viral diversity was calculated using Shannon entropy and population nucleotide diversity with a 2% variant cutoff. Our data showed (i) a higher viral diversity in the X region at baseline than the core/polymerase/surface regions, (ii) higher core/surface viral diversity at baseline for patients with seroconversion, (iii) an expected reduction in viral diversity after 8 weeks of TDF treatment, and (iv) a drop in viral diversity at W72 for patients receiving placebo with a seroconversion (n = 7). The higher viral diversity in X was associated with higher baseline alanine aminotransferase (ALT) levels (p
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- 2021
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18. N-myc-interactor mediates microbiome induced epithelial to mesenchymal transition and is associated with chronic lung allograft dysfunction
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Jon Finan, Gary A. Visner, K. Patel, Edward B. O'Neill, Amit Gaggar, Archit Kumar, Nicole M Davis, Hari R. Mallidi, John Dunning, Andreas Seyfang, Grant D. Vestal, Nirmal S. Sharma, Jaskaran Sethi, Muling Lin, Hilary J. Goldberg, Feng Cheng, Mudassir M. Banday, and Antonio Coppolino
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Male ,0301 basic medicine ,Pulmonary and Respiratory Medicine ,Lung microbiome ,Epithelial-Mesenchymal Transition ,Down-Regulation ,03 medical and health sciences ,0302 clinical medicine ,Western blot ,Downregulation and upregulation ,RNA, Ribosomal, 16S ,Humans ,Medicine ,Microbiome ,Epithelial–mesenchymal transition ,N-myc-interactor ,Retrospective Studies ,Transplantation ,medicine.diagnostic_test ,business.industry ,Microbiota ,Intracellular Signaling Peptides and Proteins ,Epithelial Cells ,Middle Aged ,Amplicon ,Allografts ,Molecular biology ,030104 developmental biology ,Real-time polymerase chain reaction ,Gene Expression Regulation ,030228 respiratory system ,Chronic Disease ,Female ,Surgery ,Primary Graft Dysfunction ,Cardiology and Cardiovascular Medicine ,business ,Follow-Up Studies ,Lung Transplantation - Abstract
Background Recent evidence suggests a role for lung microbiome in occurrence of chronic lung allograft dysfunction (CLAD). However, the mechanisms linking the microbiome to CLAD are poorly delineated. We investigated a possible mechanism involved in microbial modulation of mucosal response leading to CLAD with the hypothesis that a Proteobacteria dominant lung microbiome would inhibit N-myc-interactor (NMI) expression and induce epithelial to mesenchymal transition (EMT). Methods Explant CLAD, non-CLAD, and healthy nontransplant lung tissue were collected, as well as bronchoalveolar lavage from 14 CLAD and matched non-CLAD subjects, which were followed by 16S rRNA amplicon sequencing and quantitative polymerase chain reaction (PCR) analysis. Pseudomonas aeruginosa (PsA) or PsA-lipopolysaccharide was cocultured with primary human bronchial epithelial cells (PBEC). Western blot analysis and quantitative reverse transcription (qRT) PCR was performed to evaluate NMI expression and EMT in explants and in PsA-exposed PBECs. These experiments were repeated after siRNA silencing and upregulation (plasmid vector) of EMT regulator NMI. Results 16S rRNA amplicon analyses revealed that CLAD patients have a higher abundance of phyla Proteobacteria and reduced abundance of the phyla Bacteroidetes . At the genera level, CLAD subjects had an increased abundance of genera Pseudomonas and reduced Prevotella . Human CLAD airway cells showed a downregulation of the N-myc-interactor gene and presence of EMT. Furthermore, exposure of human primary bronchial epithelial cells to PsA resulted in downregulation of NMI and induction of an EMT phenotype while NMI upregulation resulted in attenuation of this PsA-induced EMT response. Conclusions CLAD is associated with increased bacterial biomass and a Proteobacteria enriched airway microbiome and EMT. Proteobacteria such as PsA induces EMT in human bronchial epithelial cells via NMI, demonstrating a newly uncovered mechanism by which the microbiome induces cellular metaplasia .
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- 2021
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19. Ledipasvir/Sofosbuvir for 8, 12, or 24 Weeks in Hepatitis C Patients Undergoing Dialysis for End-Stage Renal Disease
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Cheng Yuan Peng, Hadas Dvory-Sobol, Sophia Lu, Peter Buggisch, Wan-Long Chuang, Anuj Gaggar, Christophe Moreno, Alessandra Mangia, Anu Osinusi, Luigi Biancone, Marianne Camargo, Meghan E. Sise, Tsung Hui Hu, Chen-Hua Liu, Brian J. Kirby, Wei Wen Su, and Robert H. Hyland
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Adult ,Male ,Ledipasvir ,medicine.medical_specialty ,Sustained Virologic Response ,Sofosbuvir ,medicine.medical_treatment ,Hepatitis C virus ,medicine.disease_cause ,Antiviral Agents ,Drug Administration Schedule ,End stage renal disease ,chemistry.chemical_compound ,Internal medicine ,medicine ,Humans ,Adverse effect ,Dialysis ,Aged ,Aged, 80 and over ,Fluorenes ,Hepatology ,business.industry ,Gastroenterology ,Hepatitis C ,Middle Aged ,medicine.disease ,Discontinuation ,Treatment Outcome ,chemistry ,Kidney Failure, Chronic ,Benzimidazoles ,Female ,business ,medicine.drug - Abstract
Introduction We evaluated 8, 12, or 24 weeks of ledipasvir/sofosbuvir in patients with hepatitis C virus and end-stage renal disease undergoing dialysis. Methods Primary efficacy end point was sustained virologic response 12 weeks after treatment. Primary safety end point was treatment discontinuation because of adverse events (AEs). Results Ninety-four percent (89/95) achieved sustained virologic response 12 weeks after treatment. Six patients died during treatment (n = 4) or before study completion (n = 2); no deaths were related to treatment. No patients discontinued treatment because of AEs. Thirteen percent had serious AEs; none were related to treatment. Discussion Treatment with ledipasvir/sofosbuvir was safe and effective in patients with end-stage renal disease undergoing dialysis.
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- 2021
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20. Switching away from Cigarettes across 12 Months among Adult Smokers Purchasing the JUUL System
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Dish Lamichhane, Erik M. Augustson, Gem M Le, Cameron Hatcher, Arzoo Gaggar, Saul Shiffman, Shivaani Prakash, and Nicholas I. Goldenson
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Adult ,Male ,Smokers ,Health (social science) ,Social Psychology ,business.industry ,Vaping ,Public Health, Environmental and Occupational Health ,Repeated measures design ,Mean age ,Electronic Nicotine Delivery Systems ,Logistic regression ,Smoking history ,Cigarette Smoking ,Cigarette smoking ,Humans ,Medicine ,Female ,Smoking Cessation ,Prospective Studies ,business ,Demography - Abstract
Objectives: In this study, we assessed complete switching away from cigarette smoking among adult smokers who purchased a JUUL Starter Kit (JSK). Methods: Adult (age ≥ 21) established smokers (smoked ≥ 100 lifetime cigarettes) who purchased a JSK in 2018 were invited to complete online surveys 1, 2, 3, 6, 9 and 12 months after initial JSK purchase. Point prevalence of switching (no past 30-day smoking) was assessed at each follow-up. Repeated measures logistic regression models evaluated associations of sociodemographic factors, baseline smoking characteristics and time-varying JUUL System ("JUUL") use characteristics and switching across the 12-month period. Results: Respondents (N = 17,986) were 55.0% male, 78.3% white, mean age = 32.65 years (SD = 10.81), mean baseline cigarettes/day = 11.10 (SD = 8.16). The proportion self-reporting switching increased over time: one-month (27.2%[3718/13,650]), 2-month (36.4%[4926/13,533]), 3-month (41.0%[5434/13,257]), 6-month (46.6%[5411/11,621]), 9-month (49.4%[6017/12,186]), and 12-month (51.2%[6106/11,919]); 33.1% reported switching at both 9-month and 12-month follow-ups. In prospective analyses, smokers with lower cigarette dependence, shorter smoking history, lower cigarette consumption, more frequent JUUL use, greater satisfaction from initial JUUL use, and higher JUUL dependence were significantly more likely to switch. Conclusions: Rates of switching with JUUL increased over time. Over 50% of respondents reported complete switching away from cigarettes 12 months following purchase. Greater use of and dependence on JUUL predicted switching.
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- 2021
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21. MicroRNA 219-5p inhibits alveolarization by reducing platelet derived growth factor receptor-alpha
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Gloria S. Pryhuber, Namasivayam Ambalavanan, Luhua Qiao, Amelia Freeman, Nelida Olave, Gabriel Rezonzew, Amit Gaggar, Charitharth Vivek Lal, Brian Halloran, Trent E. Tipple, and Samuel J. Gentle
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0301 basic medicine ,medicine.medical_specialty ,Receptor, Platelet-Derived Growth Factor alpha ,Platelet-Derived Growth Factor Receptor Alpha ,Alpha (ethology) ,In situ hybridization ,Cohort Studies ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Internal medicine ,microRNA ,medicine ,Animals ,Humans ,Prospective Studies ,Receptor ,Lung ,Hyperoxia ,lcsh:RC705-779 ,Continuous Positive Airway Pressure ,business.industry ,Research ,Infant, Newborn ,Infant ,lcsh:Diseases of the respiratory system ,medicine.disease ,Bronchopulmonary dysplasia ,microRNAs ,Mice, Inbred C57BL ,Pulmonary Alveoli ,030104 developmental biology ,Endocrinology ,medicine.anatomical_structure ,Animals, Newborn ,030220 oncology & carcinogenesis ,Lung development ,medicine.symptom ,business ,Infant, Premature - Abstract
BackgroundMicroRNA (miR) are small conserved RNA that regulate gene expression post-transcription. Previous genome-wide analysis studies in preterm infants indicate that pathways of miR 219-5p are important in infants with Bronchopulmonary Dysplasia (BPD).MethodsHere we report a prospective cohort study of extremely preterm neonates wherein infants diagnosed with severe BPD expressed increased airway miR-219-5p and decreased platelet derived growth factor receptor alpha (PDGFR-α), a target of mir-219-5p and a key regulator of alveolarization, compared to post-conception age-matched term infants.ResultsmiR-219-5p was highly expressed in the pulmonary epithelial lining in lungs of infants with BPD by in situhybridizationof human infant lungs. In both in vitro and in vivo (mouse) models of BPD, miR-219-5p was increased on exposure to hyperoxia compared with the normoxia control, with a complementary decrease of PDGFR-α. To further confirm the target relationship between miR‐219 and PDGFR-α, pulmonary epithelial cells (MLE12) and lung primary fibroblasts were treated with a mimic of miR-219-5p and a locked nucleic acid (LNA) based inhibitor of miR-219-5p. In comparison with the control group, the level of miR‐219 increased significantly after miR‐219 mimic treatment, while the level of PDGFR-α declined markedly. LNA exposure increased PDGFR-α. Moreover, in BPD mouse model, over-expression of miR-219-5p inhibited alveolar development, indicated by larger alveolar spaces accompanied by reduced septation.ConclusionsTaken together, our results demonstrate that increased miR-219-5p contributes to the pathogenesis of BPD by targeting and reducing PDGFR-α. The use of specific miRNA antagonists may be a therapeutic strategy for preventing the development of BPD.
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- 2021
22. Compassionate Use of Remdesivir for Patients with Severe Covid-19
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Jennifer Cunningham, Marta Mora-Rillo, Robert P. Myers, Gary M. Green, Polly Desai, Toshitaka Maeno, Antonella D’Arminio Monforte, Yoshikazu Mutoh, Emanuele Nicastri, Ilana Henne, Susanna K. Tan, Erika Asperges, Jonathan Grein, Saad Ismail, Alex Studemeister, Rentaro Oda, Anuj Gaggar, Anu Osinusi, Kikuo Yo, Erwan L’Her, Huyen Cao, Hideaki Kato, Duc Nguyen, Seema Ahmed, Daniel Shin, Marco Massari, John Redinski, Giuseppe Lapadula, Lijie Zhong, Shingo Chihara, Laura Telep, Alexander Zoufaly, Daniel Chelliah, Ewa Verweij, Timothy Flanigan, Lucinda Winterbourne, Robertino Mera, Eugenia Quiros-Roldan, Diana M. Brainard, Adam DeZure, Leighann Timbs, Norio Ohmagari, Stuart H. Cohen, Sumit Majumder, Richard Childs, François-Xavier Lescure, Jorge Bernett, Emon Elboudwarej, Yang Zhao, Anand Chokkalingam, Scott Sellers, George Diaz, Torsten Feldt, Margaret L. Green, Danny Chen, Antonella Castagna, Grein, J, Ohmagari, N, Shin, D, Diaz, G, Asperges, E, Castagna, A, Feldt, T, Green, G, Green, M, Lescure, F, Nicastri, E, Oda, R, Yo, K, Quiros-Roldan, E, Studemeister, A, Redinski, J, Ahmed, S, Bernett, J, Chelliah, D, Chen, D, Chihara, S, Cohen, S, Cunningham, J, D'Arminio Monforte, A, Ismail, S, Kato, H, Lapadula, G, L'Her, E, Maeno, T, Majumder, S, Massari, M, Mora-Rillo, M, Mutoh, Y, Nguyen, D, Verweij, E, Zoufaly, A, Osinusi, A, Dezure, A, Zhao, Y, Zhong, L, Chokkalingam, A, Elboudwarej, E, Telep, L, Timbs, L, Henne, I, Sellers, S, Cao, H, Tan, S, Winterbourne, L, Desai, P, Mera, R, Gaggar, A, Myers, R, Brainard, D, Childs, R, Flanigan, T, Grein, J., Ohmagari, N., Shin, D., Diaz, G., Asperges, E., Castagna, A., Feldt, T., Green, G., Green, M. L., Lescure, F. -X., Nicastri, E., Oda, R., Yo, K., Quiros-Roldan, E., Studemeister, A., Redinski, J., Ahmed, S., Bernett, J., Chelliah, D., Chen, D., Chihara, S., Cohen, S. H., Cunningham, J., D'Arminio Monforte, A., Ismail, S., Kato, H., Lapadula, G., L'Her, E., Maeno, T., Majumder, S., Massari, M., Mora-Rillo, M., Mutoh, Y., Nguyen, D., Verweij, E., Zoufaly, A., Osinusi, A. O., Dezure, A., Zhao, Y., Zhong, L., Chokkalingam, A., Elboudwarej, E., Telep, L., Timbs, L., Henne, I., Sellers, S., Cao, H., Tan, S. K., Winterbourne, L., Desai, P., Mera, R., Gaggar, A., Myers, R. P., Brainard, D. M., Childs, R., and Flanigan, T.
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Compassionate Use Trials ,Male ,viruses ,030204 cardiovascular system & hematology ,Pharmacology ,Medical and Health Sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Japan ,80 and over ,Medicine ,030212 general & internal medicine ,Viral ,Lung ,Polymerase ,Aged, 80 and over ,Alanine ,biology ,Respiration ,General Medicine ,Prodrug ,Middle Aged ,humanities ,Europe ,Infectious Diseases ,6.1 Pharmaceuticals ,Artificial ,Administration ,Original Article ,Administration, Intravenous ,Female ,Intravenous ,Coronavirus Infections ,Human ,Adenosine monophosphate ,United State ,Adult ,Canada ,Coronavirus disease 2019 (COVID-19) ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Clinical Trials and Supportive Activities ,Pneumonia, Viral ,Administration, Intravenou ,Antiviral Agents ,03 medical and health sciences ,Betacoronavirus ,Young Adult ,Clinical Research ,General & Internal Medicine ,Humans ,Pandemics ,Aged ,Antiviral Agent ,Betacoronaviru ,Pandemic ,business.industry ,Coronavirus Infection ,SARS-CoV-2 ,Prevention ,Compassionate Use ,Evaluation of treatments and therapeutic interventions ,COVID-19 ,Pneumonia ,Respiration, Artificial ,In vitro ,Adenosine Monophosphate ,United States ,COVID-19 Drug Treatment ,Coronavirus ,Emerging Infectious Diseases ,Good Health and Well Being ,chemistry ,biology.protein ,business - Abstract
Background Remdesivir, a nucleotide analogue prodrug that inhibits viral RNA polymerases, has shown in vitro activity against SARS-CoV-2. Methods We provided remdesivir on a compassionate-use basis to patients hospitalized with Covid-19, the illness caused by infection with SARS-CoV-2. Patients were those with confirmed SARS-CoV-2 infection who had an oxygen saturation of 94% or less while they were breathing ambient air or who were receiving oxygen support. Patients received a 10-day course of remdesivir, consisting of 200 mg administered intravenously on day 1, followed by 100 mg daily for the remaining 9 days of treatment. This report is based on data from patients who received remdesivir during the period from January 25, 2020, through March 7, 2020, and have clinical data for at least 1 subsequent day. Results Of the 61 patients who received at least one dose of remdesivir, data from 8 could not be analyzed (including 7 patients with no post-treatment data and 1 with a dosing error). Of the 53 patients whose data were analyzed, 22 were in the United States, 22 in Europe or Canada, and 9 in Japan. At baseline, 30 patients (57%) were receiving mechanical ventilation and 4 (8%) were receiving extracorporeal membrane oxygenation. During a median follow-up of 18 days, 36 patients (68%) had an improvement in oxygen-support class, including 17 of 30 patients (57%) receiving mechanical ventilation who were extubated. A total of 25 patients (47%) were discharged, and 7 patients (13%) died; mortality was 18% (6 of 34) among patients receiving invasive ventilation and 5% (1 of 19) among those not receiving invasive ventilation. Conclusions In this cohort of patients hospitalized for severe Covid-19 who were treated with compassionate-use remdesivir, clinical improvement was observed in 36 of 53 patients (68%). Measurement of efficacy will require ongoing randomized, placebo-controlled trials of remdesivir therapy. (Funded by Gilead Sciences.)
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- 2020
23. Genetic regulation of expression of leukotriene A4 hydrolase
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Tomasz Szul, Peter Castaldi, Michael H. Cho, J. Edwin Blalock, and Amit Gaggar
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Medicine - Abstract
In chronic inflammatory lung disorders such as chronic obstructive pulmonary disease (COPD), the concurrent organ-specific and systemic inflammatory responses lead to airway remodelling and vascular dysfunction. Although a major common risk factor for COPD, cigarette smoke alone cannot explain the progression of this disease; there is increasing evidence that genetic predisposition also plays a role in COPD susceptibility and progression. A key enzyme in chronic lung inflammation is leukotriene A4 hydrolase (LTA4H). With its aminopeptidase activity, LTA4H degrades the neutrophil chemoattractant tripeptide PGP. In this study, we used the luciferase reporter gene analysis system and quantitative trait locus analysis to explore the impact of single-nucleotide polymorphisms (SNPs) in the putative promoter region of LTA4H on LTA4H expression. We show that not only is the putative promoter of LTA4H larger than previously reported but also that SNPs in the expanded promoter region regulate expression of LTA4H both in cell-based systems and in peripheral blood samples from human subjects. These findings provide significant evidence for an active region upstream of the previously reported LTA4H promoter, which may have implications related to ongoing inflammatory processes in chronic lung disease.
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- 2016
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24. PNPLA3 polymorphisms are associated with raised alanine aminotransferase levels in hepatitis C virus genotype 3
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Tanvi Agrawal, Nirupma Trehanpati, Shyam Kottilil, Abhijit Choudhary, Sameer Shah, Anuj Gaggar, Padaki Nagaraja Rao, and Mani Subramanian
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Adult ,Genotype ,Hepatitis C virus ,India ,Single-nucleotide polymorphism ,Hepacivirus ,medicine.disease_cause ,Polymorphism, Single Nucleotide ,medicine ,Humans ,Allele ,Gene ,Genotyping ,business.industry ,Interleukins ,Gastroenterology ,Membrane Proteins ,virus diseases ,Alanine Transaminase ,Lipase ,Hepatitis C, Chronic ,Middle Aged ,digestive system diseases ,Interleukin 28B ,Immunology ,business ,Viral load - Abstract
Background and study aims Hepatitis C virus (HCV) infection is one of the leading causes of end-stage liver diseases. This study aimed to determine the association between polymorphisms in interleukin 28B (IL28B), PNPLA3, toll-like receptor 7 (TLR7), nucleotide-binding oligomerization domain-containing protein 2 (NOD2) and retinoic inducible gene-I (RIG-I) and HCV genotype and clinical presentation in an Indian population. Patients and methods A total of 500 patients with chronic HCV were enrolled in 19 centres across India. Genomic DNA was extracted from whole blood samples, and single nucleotide polymorphisms (SNPs) for IL28B, PNPLA3, TLR7, NOD2 and RIG-I genes were genotyped by real-time PCR using a TaqManSNP genotyping assay. Results The mean age of the patients was 45 + 13 years, and the most common genotype observed was HCV genotype 3 (54%), followed by genotype 1 (24%). Although the allelic frequencies of TLR7, NOD2 and RIG-I were in significant disequilibrium in HCV patients compared with those in controls, the PNPLA3 polymorphism correlated significantly with higher viral load and alanine aminotransferase (ALT) levels in genotype 3 patients. Patients with PNPLA3 CG/GG genotypes, along with IL28B genotype CC, had higher levels of ALT than those with other genotypes. Conclusion These results indicate that PNPLA3 polymorphisms are associated with higher ALT levels in HCV genotype 3 patients in India and can help in identifying people who are at greater risk of developing HCV-associated liver diseases.
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- 2020
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25. Child Sexual Abuse during COVID-19 Pandemic
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Jugal Kishore, Monica Lakhanpal Gaggar, and Jitender
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medicine.medical_specialty ,Coronavirus disease 2019 (COVID-19) ,Physical health ,Behaviour change communication ,03 medical and health sciences ,0302 clinical medicine ,Sexual abuse ,030225 pediatrics ,Child sexual abuse ,Pandemic ,medicine ,Asset (economics) ,Psychiatry ,Psychology ,030217 neurology & neurosurgery - Abstract
Prevalence of child sexual abuse during epidemic and disaster is common. There are evidences that children are victims of sexual exploitation during the lockdown period. They undergo multiple physical and mental injuries which could last lifelong. In presence of law, the child sexual abuse will not stop till the society is sensitive enough for the child emotional and physical health need. Responsibility of care lies not only on parents but also on everybody because they are the asset of nation. Mass awareness program along with behaviour change communication could be better solution during the Covid-19 pandemic. How to cite this article:Kishore J, Gaggar ML, JitenderChild Sexual Abuse during Covid 19 Pandemic. Int J Preven Curat Comm Med 2020; 6(1): 30-36. DOI: https://doi.org/10.24321/2454.325X.202005
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- 2020
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26. Twelve weeks of ledipasvir/sofosbuvir all‐oral regimen for patients with chronic hepatitis C genotype 2 infection: Integrated analysis of three clinical trials
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E.J. Gane, Wan-Long Chuang, Yoshito Itoh, Yoshiyuki Ueno, Joe Llewellyn, Nobuyuki Enomoto, Yasuhiro Asahina, Norifumi Kawada, Anuj Gaggar, Pei-Jer Chen, Chun-Jen Liu, Gerald Crans, Hongmei Mo, Jin Youn, Takuma Matsuda, Chen-Yu Wang, and Hadas Dvory-Sobol
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Ledipasvir ,medicine.medical_specialty ,Cirrhosis ,Hepatology ,Sofosbuvir ,business.industry ,Hepatitis C virus ,medicine.disease ,medicine.disease_cause ,Gastroenterology ,Clinical trial ,03 medical and health sciences ,chemistry.chemical_compound ,Regimen ,0302 clinical medicine ,Infectious Diseases ,chemistry ,030220 oncology & carcinogenesis ,Internal medicine ,Genotype ,medicine ,030211 gastroenterology & hepatology ,business ,Adverse effect ,medicine.drug - Abstract
Aim The combination of ledipasvir and sofosbuvir (LDV/SOF) has been approved for the treatment of various hepatitis C virus (HCV) genotypes across many countries. This article presents an integrated analysis of three prospective phase II/III trials in the Asia-Pacific region to evaluate the efficacy and safety of 12 weeks of LDV/SOF in HCV genotype 2 patients without cirrhosis or with compensated cirrhosis. Methods A total of 200 patients were included in the integrated analysis. The primary end-point was the rate of sustained virologic response for 12 weeks after the end of therapy (SVR12), analyzed by fibrosis stage, treatment history, HCV genotype subtype, and presence of baseline resistance-associated substitutions (RAS). Safety was evaluated by adverse events and laboratory abnormalities. Results Twelve weeks of treatment with LDV/SOF was associated with high SVR12 rates (overall 98%) in patients with genotype 2 HCV, irrespective of fibrosis stage, treatment history, genotype 2 subtype, and presence of baseline non-structural protein 5A resistance-associated substitution (NS5A RAS), and LDV/SOF was well tolerated. Conclusions Twelve weeks of treatment with LDV/SOF provides a highly effective and safe treatment for patients with genotype 2 HCV, including those with advanced fibrosis. As a ribavirin-free and protease inhibitor-free regimen with minimal on-treatment monitoring requirements, LDV/SOF can potentially play a crucial role in achieving the WHO's goal of HCV elimination.
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- 2020
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27. Damage to red blood cells during whole blood storage
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Jindong Li, John B. Holcomb, Marisa B. Marques, Joo-Yeun Oh, Xin Xu, Kristopher R. Genschmer, Amit Gaggar, Jan O. Jansen, Jean-Francois Pittet, and Rakesh P. Patel
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Erythrocytes ,Hematocrit ,Nitric Oxide ,Critical Care and Intensive Care Medicine ,medicine.disease_cause ,Hemolysis ,Nitric oxide ,Andrology ,Hemoglobins ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Cell-Derived Microparticles ,Humans ,Medicine ,Citrates ,Expiration ,Heme ,Whole blood ,medicine.diagnostic_test ,business.industry ,030208 emergency & critical care medicine ,Peroxiredoxins ,Carbon Dioxide ,medicine.disease ,Oxygen ,Oxidative Stress ,Glucose ,chemistry ,Blood Preservation ,Surgery ,business ,Packed red blood cells ,Oxidation-Reduction ,Oxidative stress - Abstract
Background Transfusion with stored whole blood (WB) is increasingly routine practice to resuscitate bleeding trauma patients. Storage of packed red blood cells (pRBC) results in multiple biochemical, structural, and metabolic changes, referred to as to the storage lesion that may mediate adverse effects associated with transfusion of older RBC units. These include increased hemolysis, oxidative stress, and accelerated scavenging of nitric oxide (NO). Whether similar changes occur to stored WB is unclear and are characterized in this study. Methods Ten WB units, in citrate-phosphate-dextrose, were purchased from the American Red Cross and changes in hemolysis (increased free hemoglobin, heme, and microparticles), oxidative stress indexed by redox cycling of peroxiredoxin-2 (Prx-2) and NO-scavenging kinetics were determined at different storage times until expiration. Results Microparticle number and free hemoglobin, but not heme, increased in a storage time-dependent manner. When normalized to the initial number of RBCs in stored WB units, hemolysis rates were similar to those reported for pRBCs. Prx-2 recycling kinetics were slower at expiration compared with earlier storage times. Rates of NO dioxygenation did not change with storage, but were decreased compared with freshly isolated RBCs. Conclusion Storage of WB results in changes associated with the pRBC storage lesion but not for all parameters tested. The relative rate of hemolysis (indexed by free hemoglobin and microparticles) and oxidative stress was similar to that of pRBCs. However, the absolute level of hemolysis products were lower due to lower hematocrit of stored WB units. The clinical significance of these findings requires further investigation.
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- 2020
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28. Diminished hepatic IFN response following HCV clearance triggers HBV reactivation in coinfection
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Yoshiyasu Karino, Johannes Vermehren, Xiaoming Cheng, Marcus M. Mücke, Shuhei Hige, Hiroshi Aikata, Takuro Uchida, Anuj Gaggar, Stefan Zeuzem, Pei-Jer Chen, T. Jake Liang, Chun-Jen Liu, Nami Mori, Yuchen Xia, Mitsutaka Osawa, Yuji Teraoka, Kazuaki Chayama, Michio Imamura, Keiji Tsuji, Vithika Suri, and Regina Umarova
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0301 basic medicine ,Hepatitis B virus ,Chemokine ,Viremia ,Hepacivirus ,medicine.disease_cause ,CCL5 ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Interferon ,medicine ,Animals ,Humans ,CXCL10 ,Chemokine CCL5 ,Hepatitis ,biology ,Coinfection ,business.industry ,virus diseases ,General Medicine ,Hepatitis B ,medicine.disease ,Hepatitis C ,Virology ,digestive system diseases ,Chemokine CXCL10 ,030104 developmental biology ,Liver ,030220 oncology & carcinogenesis ,Superinfection ,Commentary ,biology.protein ,Virus Activation ,Interferons ,business ,medicine.drug - Abstract
In patients with HBV and HCV coinfection, HBV reactivation leading to severe hepatitis has been reported with the use of direct-acting antivirals (DAAs) to treat HCV infection. Here we studied the molecular mechanisms behind this viral interaction. In coinfected cell culture and humanized mice, HBV replication was suppressed by HCV coinfection. In vitro, HBV suppression was attenuated when interferon (IFN) signaling was blocked. In vivo, HBV viremia, after initial suppression by HCV superinfection, rebounded following HCV clearance by DAA treatment that was accompanied by a reduced hepatic IFN response. Using blood samples of coinfected patients, IFN-stimulated gene products including C-X-C motif chemokine 10 (CXCL10), C-C motif chemokine ligand 5 (CCL5), and alanine aminotransferase (ALT) were identified to have predictive value for HBV reactivation after HCV clearance. Taken together, our data suggest that HBV reactivation is a result of diminished hepatic IFN response following HCV clearance and identify serologic markers that can predict HBV reactivation in DAA-treated HBV-HCV-coinfected persons.
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- 2020
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29. Human Fetal Lungs Harbor a Microbiome Signature
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Namasivayam Ambalavanan, Amit Gaggar, Soula Danopoulos, Micheal MacAogain, Sanjay H. Chotirmall, Denise Al Alam, Nur A'tikah Binte Mohamed Ali, Brendan H. Grubbs, David Warburton, and Charitharth Vivek Lal
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Pulmonary and Respiratory Medicine ,Pregnancy ,business.industry ,MEDLINE ,Gestational age ,RNA ,Ribosomal RNA ,Critical Care and Intensive Care Medicine ,medicine.disease ,Bioinformatics ,Metagenomics ,Correspondence ,Human fetal ,Medicine ,Microbiome ,business - Published
- 2020
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30. Effects of hyperoxia on alveolar and pulmonary vascular development in germ-free mice
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Gabriel Rezonzew, Xin Xu, Kalsang Dolma, Namasivayam Ambalavanan, Gregory A. Payne, Charitharth Vivek Lal, J. Edwin Blalock, Ameilia E. Freeman, Amit Gaggar, and Tamas Jilling
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0301 basic medicine ,Pulmonary and Respiratory Medicine ,Hyperoxia ,Lung microbiome ,Physiology ,business.industry ,Cell Biology ,respiratory system ,Microbial dysbiosis ,medicine.disease ,respiratory tract diseases ,Very preterm ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,030228 respiratory system ,Bronchopulmonary dysplasia ,Physiology (medical) ,Immunology ,medicine ,Microbiome ,medicine.symptom ,Airway ,business - Abstract
Airway microbial dysbiosis is associated with subsequent bronchopulmonary dysplasia (BPD) development in very preterm infants. However, the relationship of airway microbiome in normal pulmonary development has not been defined. To better understand the role of the airway microbiome, we compared normal and abnormal alveolar and pulmonary vascular development in mice with or without a microbiome. We hypothesized that the lungs of germ-free (GF) mice would have an exaggerated phenotypic response to hyperoxia compared with non–germ-free (NGF) mice. With the use of a novel gnotobiotic hyperoxia chamber, GF and NGF mice were exposed to either normoxia or hyperoxia. Alveolar morphometry, pulmonary mechanics, echocardiograms, inflammatory markers, and measures of pulmonary hypertension were studied. GF and NGF mice in normoxia showed no difference, whereas GF mice in hyperoxia showed protected lung structure and mechanics and decreased markers of inflammation compared with NGF mice. We speculate that an increase in abundance of pathogenic bacteria in NGF mice may play a role in BPD pathogenesis by regulating the proinflammatory signaling and neutrophilic inflammation in lungs. Manipulation of the airway microbiome may be a potential therapeutic intervention in BPD and other lung diseases.
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- 2020
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31. Matrix Metalloproteinase Activity in Pediatric Acute Lung Injury
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Michele YF Kong, Amit Gaggar, Yao Li, Margaret Winkler, J Edwin Blalock, JP Clancy
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Medicine - Abstract
Pediatric Acute Lung Injury (ALI) is associated with a high mortality and morbidity, and dysregulation of matrix metalloproteinases (MMPs) may play an important role in the pathogenesis and evolution of ALI. Here we examined MMP expression and activity in pediatric ALI compared with controls. MMP-8, -9, and to a lesser extent, MMP-2, -3, -11 and -12 were identified at higher levels in lung secretions of pediatric ALI patients compared with controls. Tissue Inhibitor of Matrix metalloproteinase-1 (TIMP-1), a natural inhibitor of MMPs was detected in most ALI samples, but MMP-9:TIMP-1 ratios were high relative to controls. In subjects who remained intubated for ≥10 days, MMP-9 activity decreased, with > 80% found in the latent form. In contrast, almost all MMP-8 detected at later disease course was constitutively active. Discriminating MMP-9:TIMP-1 ratios were found in those who had a prolonged ALI course. These results identify a specific repertoire of MMP isoforms in the lung secretions of pediatric ALI patients, and demonstrate inverse changes in MMPs -8 and -9 with protracted disease.
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- 2009
32. Characterization of the liver immune microenvironment in liver biopsies from patients with chronic HBV infection
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Lauri Diehl, Becket Feierbach, Ricardo Ramirez, Neeru Bhardwaj, Jeffrey J. Wallin, Nicholas van Buuren, Scott Turner, Samuel Kim, Dmytro Kornyeyev, H.L. Chan, Abhishek Aggarwal, Patrick Marcellin, Maria Buti, Simon P. Fletcher, Vithika Suri, Hongmei Mo, Anuj Gaggar, Christina Moon, Li Li, Nam Bui, and Diana Chen
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animal diseases ,Chronic HBV ,multiplex immunofluorescence ,Inflammation ,chemical and pharmacologic phenomena ,BCR, B-cell receptor ,Immunofluorescence ,CHB, chronic HBV infection ,Immune system ,Interferon ,Immune Microenvironment ,ALT, alanine aminotransferase ,TLS, tertiary lymphoid structures ,DEG, differentially expressed gene ,Internal Medicine ,medicine ,Immunology and Allergy ,CXCL10 ,Cytotoxic T cell ,TDF, tenofovir disoproxil fumarate ,Hepatology ,medicine.diagnostic_test ,business.industry ,Intrahepatic transcriptome ,Gastroenterology ,mIF, multiplex immunofluorescence ,ssGSEA, single sample gene set enrichment analysis ,Hepatitis B ,biochemical phenomena, metabolism, and nutrition ,medicine.disease ,FFPE, formalin-fixed paraffin-embedded ,PEG-IFNα, pegylated-interferon-α ,HBeAg ,TCR, T-cell receptor ,Immunology ,bacteria ,medicine.symptom ,business ,IHC, immunohistochemistry ,medicine.drug ,Research Article - Abstract
Background & Aims We aim to describe the liver immune microenvironment by analyzing liver biopsies from patients with chronic HBV infection (CHB). Host immune cell signatures and their corresponding localization were characterized by analyzing the intrahepatic transcriptome in combination with a custom multiplex immunofluorescence panel. Method Matching FFPE and fresh frozen liver biopsies were collected from immune active patients within the open-label phase IV study GS-US-174-0149. RNA-Seq was conducted on 53 CHB liver biopsies from 46 patients. Twenty-eight of the 53 samples had matched FFPE biopsies and were stained with a 12-plex panel including cell segmentation, immune and viral biomarkers. Corresponding serum samples were screened using the MSD Human V-plex Screen Service to identify peripheral correlates for the immune microenvironment. Results Using unsupervised clustering of the transcriptome, we reveal two unique liver immune signatures classified as immune high and immune low based on the quantification of the liver infiltrate gene signatures. Multiplex immunofluorescence analysis demonstrated large periportal lymphoid aggregates in immune high samples consisting of CD4 and CD8 T cells, B cells and macrophages. Differentiation of the high and low immune microenvironments was independent of HBeAg status and peripheral viral antigen levels. In addition, longitudinal analysis indicates that treatment and normalization of ALT correlates with a decrease in liver immune infiltrate and inflammation. Finally, we screened a panel of peripheral biomarkers and identified ICAM-1 and CXCL10 as biomarkers that strongly correlate with these unique immune microenvironments. Conclusion These data provide a description of immune phenotypes in patients with CHB and show that immune responses are downregulated in the liver following nucleotide analogue treatment. This may have important implications for both the safety and efficacy of immune modulator programs aimed at HBV cure. Lay summary Liver biopsies from patients with chronic hepatitis B were submitted to RNA-Seq and multiplex immunofluorescence and identified two different liver immune microenvironments: immune high and immune low. Immune high patients showed elevated immune pathways, including interferon signaling pathways, and increase presence of immune cells. Longitudinal analysis of biopsies from treatment experienced patients showed that treatment correlates with a marked decrease in inflammation and these findings may have important implications for both safety and efficacy of immune modulator programs for HBV cure., Graphical abstract, Highlights • Two different liver immune microenvironments were identified in patients with chronic hepatitis B: immune high and immune low. • Immune high patients had elevated immune pathway activity and immune cell signatures corresponding to B cells, T cells and macrophages. • Antiviral treatment and normalization of ALT correlates with a marked decrease in liver immune infiltrate and inflammation. • CXCL10 and ICAM-1 were identified as peripheral biomarkers that correlated with these differentiated immune microenvironments.
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- 2021
33. IDDF2021-ABS-0080 96-week efficacy and safety of tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide (TAF) switch vs. continued TDF treatment among virologically-suppressed hepatitis B patients of asian ethnicity
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Sang Hoon Ahn, Alnoor Ramji, Scott Fung, Chi-Yi Chen, Hie-Won Hann, Yang Zhao, Shalini Sethi, Wan-Long Chuang, Ho Bae, Leland J. Yee, John F. Flaherty, Carol Yee Kwan Chan, Young-Suk Lim, Xiaoli Ma, Pietro Lampertico, Yoon Jun Kim, Jia-Horng Kao, Anuj Gaggar, Edward Tam, Henry Lik-Yuen Chan, and June Sung Lee
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medicine.medical_specialty ,Tenofovir ,business.industry ,Internal medicine ,medicine ,Asian ethnicity ,Hepatitis B ,medicine.disease ,business ,Tenofovir alafenamide ,Gastroenterology ,medicine.drug - Published
- 2021
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34. IDDF2021-ABS-0078 Switching from tenofovir disoproxil fumarate (TDF) and/or other oral antivirals (OAVS) to tenofovir alafenamide (TAF) in virally suppressed chronic hepatitis B (CHB) patients with moderate or severe renal impairment, or with end-stage renal disease (ESRD)
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Sang Hoon Ahn, Giulio Marchesini, Carla S. Coffin, Wan-Long Chuang, Aric J. Hui, Yi-Hsang Huang, Yang Zhao, Susanna K. Tan, Tak Yin Owen Tsang, Magdy Elkhashab, Sayed-Mohammed Jafri, Chien-Hung Chen, Harry La Janssen, Jeong Heo, John F. Flaherty, Diana M. Brainard, Claire Fournier, Kosh Agarwal, Carol Yee Kwan Chan, Young-Suk Lim, Anuj Gaggar, Edward Gane, Vithika Suri, and Pietro Lampertico
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High rate ,medicine.medical_specialty ,Cirrhosis ,Tenofovir ,business.industry ,Osteoporosis ,urologic and male genital diseases ,medicine.disease ,Gastroenterology ,Tenofovir alafenamide ,End stage renal disease ,Chronic hepatitis ,Internal medicine ,Medicine ,Viral suppression ,business ,medicine.drug - Abstract
Background We have previously shown in renally impaired (RI) CHB patients, including those with ESRD on HD, that switching to TAF from TDF and/or other OAVs maintains high rates of viral suppression with stable bone and renal safety parameters at Week 48. Here we present the final Week 96 results. Methods In this study, virally suppressed CHB patients (HBV DNA Results Of 93 patients (mod-severe RI 78; ESRD on HD 15), most (74%) were male and Asian (77%), 51% ≥65 y, 83% HBeAg-negative, 34% cirrhosis, and median ALT 17 U/L. Up to 24% had osteoporosis at hip and/or spine, with most having comorbidities. Twelve (13%; 11 mod-severe RI and 1 ESRD) patients discontinued the study early (5-withdrew consent, 3-deaths [none treatment-related], 2-AE, 2-investigator decision). Viral suppression (HBV DNA Conclusions Renally-impaired CHB patients, including ESRD patients on HD, who were switched to TAF from TDF and/or other OAVs maintained high rates of viral suppression, and bone and renal parameters remained stable or slightly improved after 2 years of treatment.
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- 2021
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35. IDDF2021-ABS-0079 Switching from tenofovir disoproxil fumarate (TDF) and/or other oral antivirals (OAVS) to tenofovir alafenamide (TAF) in virally suppressed chronic hepatitis B (CHB) patients with hepatic impairment: final 2-year efficacy and safety results from a phase 2
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Harry La Janssen, Chun-Yen Lin, Aric J. Hui, Huy N. Trinh, Claire Fournier, Yang Zhao, Ho Bae, Vithika Suri, Stephen D. Ryder, John F. Flaherty, Young-Suk Lim, Anuj Gaggar, Carol Yee Kwan Chan, Susanna K. Tan, Dianna M Brainard, Jeong Heo, Wan-Long Chuang, and Tak Yin Owen Tsang
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medicine.medical_specialty ,Tenofovir ,business.industry ,Hepatic impairment ,Osteoporosis ,Phases of clinical research ,Aspiration pneumonia ,medicine.disease ,Tenofovir alafenamide ,Gastroenterology ,Respiratory failure ,Chronic hepatitis ,Internal medicine ,medicine ,business ,medicine.drug - Abstract
Background We have previously shown that in hepatically impaired CHB patients, switching to TAF from TDF and/or other OAVs maintains high rates of viral suppression with stable bone and renal safety parameters through 48 weeks. Here we present our final 2-year (Week 96) results. Methods In this Phase 2 study (NCT03180619), virally suppressed CHB patients (HBV DNA Results Of 31 patients enrolled, mean age was 55 y (29% ≥60 y), 68% male, 81% Asian, and 90% HBeAg-negative; median (Q1, Q3) CTP and MELD scores were 6 (5, 8) and 10 (7.5, 14.2), respectively, median eGFRCG98.5 mL/min; 19% had osteoporosis on spine DXA. Twenty-five (81%) patients completed 96 weeks of TAF treatment (6 discontinued early: 2-withdrew consent, 1-adverse event [AE; Grade 2 creatinine increase], 1-investigator decision, and 2-death [respiratory failure and aspiration pneumonia - both not treatment-related]). Week 96 efficacy/safety results are summarized in the Table. 96% of patients on TAF treatment had HBV DNA Conclusions At 2 years, CHB patients with hepatic impairment who were switched to TAF maintained high rates of viral suppression and normal ALT values while bone and renal parameters remained stable.
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- 2021
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36. Nontypeable Haemophilus influenzae redox recycling of protein thiols promotes resistance to oxidative killing and bacterial survival in biofilms in a smoke related infection model
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Xin Xu, Amit Gaggar, Benjamin C. Hunt, and W. Edward Swords
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biology ,Chemistry ,Biofilm ,Biofilm matrix ,Neutrophil extracellular traps ,Protein oxidation ,medicine.disease_cause ,biology.organism_classification ,Microbiology ,Haemophilus influenzae ,otorhinolaryngologic diseases ,medicine ,Peroxiredoxin ,Bacteria ,Oxidative stress - Abstract
Smoke exposure is a risk factor for community acquired pneumonia, which is typically caused by host adapted opportunists like nontypeable Haemophilus influenzae (NTHi). Genomic analyses of NTHi revealed homologs of enzymes involved in thiol metabolism, which can have key roles in oxidant resistance. Using a clinical NTHi isolate (NTHi 7P49H1), we generated isogenic mutant bacterial strains in which homologs of glutathione reductase (NTHI 0251), thiol peroxidase (NTHI 0361), thiol peroxidase (NTHI 0907), thioredoxin reductase (NTHI 1327) and glutaredoxin/peroxiredoxin (NTHI 0705) were inactivated. Bacterial protein analyses revealed significant increases in protein oxidation after oxidative stress for all the mutant strains. Similarly, each of these mutants were less resistant to oxidative killing compared with the parental strain; these phenotypes were reversed by genetic complementation. Quantitative confocal analysis of biofilms showed reducted biofilm thickness and density, and significant sensitization of bacteria within the biofilm structure to oxidative killing for thiol mutant strains. Smoke-exposed mice infected with NTHi 7P49H1 showed significantly increased lung bacterial load, as compared to control mice. Immunofluorescent staining of lung tissues showed NTHi communities on the lung mucosa, interspersed with host neutrophil extracellular traps; these bacteria had surface moieties associated with the Hi biofilm matrix, and transcript profiles consistent with NTHi biofilms. In contrast, infection with the panel of NTHi mutants showed significant decrease in lung bacterial load. Comparable results were observed in bactericidal assays with neutrophil extracellular traps in vitro. Thus, we conclude that thiol mediated redox homeostasis promotes persistence of NTHi within biofilm communities.ImportanceChronic bacterial respiratory infections are a significant problem for smoke exposed individuals, especially those with chronic obstructive pulmonary disease (COPD). These infections often persist despite antibiotic use. Thus, the bacteria remain and contribute to the development of inflammation and other respiratory problems. Respiratory bacteria often form biofilms within the lungs, while growing in a biofilm their antibiotic and oxidative stress resistance is incredibly heightened. It is well documented that redox homeostasis genes are upregulated during this phase of growth. Many common respiratory pathogens such as NTHi and Streptococcus pneumoniae are reliant on scavenging from the host the necessary components they need to maintain these redox systems. This work here begins to lay down the foundation for exploiting this requirement and thiol redox homeostasis pathways of these bacteria as a therapeutic target for managing chronic respiratory bacterial infections, which are resistant to traditional antibiotic treatments alone.
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- 2021
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37. Megakaryocytes are a Novel SARS-CoV-2 Infection Target and Risk Factor for Mortality and Multi-Organ Failure
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Andrew B. Crouse, Ram Prasad, Blake Frey, Maria B. Grant, Sivani B. Reddy, Sarah Sterrett, Nathan Erdmann, Vidya Sagar Hanumanthu, Michael J. Patton, Peng Li, Seth D. Fortmann, Cristiano P. Vieira, Amit Gaggar, Jeremy Zucker, Forest Huls, Matthew Might, Paul A. Goepfert, and Jason L. Floyd
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Mechanical ventilation ,business.industry ,medicine.medical_treatment ,Acute kidney injury ,medicine.disease ,S100A8 ,Herd immunity ,Respiratory failure ,Immunology ,Medicine ,Biomarker (medicine) ,Risk factor ,Calprotectin ,business - Abstract
Discovery of a biomarker for patients at high risk of progression to severe Coronavirus Disease 2019 (COVID-19) is critical for clinical management, particularly in areas of the world where widespread vaccine distribution and herd immunity have yet to be achieved. Herein, we characterize peripheral blood from 218 COVID-19 patients with flow cytometry and provide evidence that megakaryocytes are a target for infection by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). We demonstrate a positive correlation between infected megakaryocytes expressing the protein calprotectin (also called S100A8/A9), a known marker of COVID-19 severity. Additionally, we show that infected, calprotectin expressing megakaryocytes are correlated with COVID-19 severity and are a prognostic indicator of 30-day clinical outcomes including respiratory failure, thrombotic events, acute kidney injury (AKI), ICU admission, and mechanical ventilation. These findings represent a novel SARS-CoV-2 infection target with significant clinical implications as a biomarker for clinical outcomes associated with severe COVID-19.
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- 2021
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38. Proline-Glycine-Proline Peptides Are Critical in the Development of Smoke-induced Emphysema
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Xin Xu, Gert Folkerts, Liliana Viera, Mariam Sadik, George M. Solomon, Preston E. Bratcher, Tomasz Szul, J. Edwin Blalock, Amit Gaggar, J. Michael Wells, Mojtaba Abdul Roda, Tarek Abdalla, Carmel M. McNicholas, and Frank A. Redegeld
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0301 basic medicine ,Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Clinical Biochemistry ,Inflammation ,Stimulation ,03 medical and health sciences ,0302 clinical medicine ,Right ventricular hypertrophy ,Internal medicine ,medicine ,Macrophage ,CXC chemokine receptors ,Molecular Biology ,Smoke ,COPD ,Lung ,business.industry ,Cell Biology ,respiratory system ,medicine.disease ,respiratory tract diseases ,030104 developmental biology ,Endocrinology ,medicine.anatomical_structure ,030228 respiratory system ,medicine.symptom ,business - Abstract
Chronic obstructive pulmonary disease (COPD) is a major cause of mortality worldwide and is characterized by an excessive airway neutrophilic response. The neutrophil chemoattractant proline-glycine-proline (PGP) and its more potent acetylated form (acPGP) have been found to be elevated in patients with COPD and act via CXCR2. Here, we investigated the impact of neutralizing PGP peptides in a murine model for emphysema. The PGP-neutralizing peptide l-arginine-threonine-arginine (RTR) was used first in a 6-week model of cigarette smoke exposure, where it attenuated lung inflammation. Then, in a model of chronic smoke exposure, mice were exposed to cigarette smoke and RTR treatment was initiated after 10 weeks of smoke exposure. This treatment was continued together with smoke exposure for another 13 weeks, for a total of 23 weeks of smoke exposure. RTR significantly inhibited neutrophil and macrophage influx into the lungs in the 6-week model of exposure. RTR also attenuated the development of emphysema, normalized lung volumes, and reduced right ventricular hypertrophy in the chronic exposure model. Murine epithelia expressed CXCR2, and this expression was increased after smoke exposure. In vitro, human bronchial epithelial cells also demonstrated robust expression of CXCR2, and stimulation of primary human bronchial epithelial cells with acPGP led to increased release of MMP-9 and IL-8. Overall, these results provide evidence that acPGP plays a critical role during the development of emphysema in cigarette smoke-induced injury, and highlight a new epithelial mechanism by which acPGP augments neutrophilic inflammation.
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- 2019
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39. Anti-PD-1 blockade with nivolumab with and without therapeutic vaccination for virally suppressed chronic hepatitis B: A pilot study
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Anh Hoa Nguyen, Christian Schwabe, G. Mani Subramanian, Daniel Verdon, P. Rod Dunbar, Anna E. S. Brooks, Edward Gane, and Anuj Gaggar
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Adult ,Male ,0301 basic medicine ,Hepatitis B virus ,medicine.medical_specialty ,HBsAg ,T-Lymphocytes ,T cell ,Programmed Cell Death 1 Receptor ,Pilot Projects ,medicine.disease_cause ,Gastroenterology ,03 medical and health sciences ,Hepatitis B, Chronic ,0302 clinical medicine ,Antigen ,Internal medicine ,medicine ,Humans ,Hepatitis B Vaccines ,Hepatitis B e Antigens ,Adverse effect ,Immune Checkpoint Inhibitors ,Aged ,Hepatitis B Surface Antigens ,Hepatology ,business.industry ,Vaccination ,Middle Aged ,Blockade ,Nivolumab ,Treatment Outcome ,030104 developmental biology ,medicine.anatomical_structure ,HBeAg ,DNA, Viral ,Female ,030211 gastroenterology & hepatology ,business ,Follow-Up Studies ,New Zealand - Abstract
Background & Aims To evaluate the hypothesis that increasing T cell frequency and activity may provide durable control of hepatitis B virus (HBV), we administered nivolumab, a programmed death receptor 1 (PD-1) inhibitor, with or without GS-4774, an HBV therapeutic vaccine, in virally suppressed patients with HBV e antigen (HBeAg)-negative chronic HBV. Methods In a phase Ib study, patients received either a single dose of nivolumab at 0.1 mg/kg (n = 2) or 0.3 mg/kg (n = 12), or 40 yeast units of GS-4774 at baseline and week 4 and 0.3 mg/kg of nivolumab at week 4 (n = 10). The primary efficacy endpoint was mean change in HBV surface antigen (HBsAg) 12 weeks after nivolumab. Safety and immunologic changes were assessed through week 24. Results There were no grade 3 or 4 adverse events or serious adverse events. All assessed patients retained T cell PD-1 receptor occupancy 6–12 weeks post-infusion, with a mean total across 0.1 and 0.3 mg/kg cohorts of 76% (95% CI 75–77), and no significant differences were observed between cohorts (p = 0.839). Patients receiving 0.3 mg/kg nivolumab without and with GS-4774 had mean declines of −0.30 (95% CI −0.46 to −0.14) and −0.16 (95% CI −0.33 to 0.01) log10 IU/ml, respectively. Patients showed significant HBsAg declines from baseline (p = 0.035) with 3 patients experiencing declines of >0.5 log10 by the end of study. One patient, whose HBsAg went from baseline 1,173 IU/ml to undetectable at week 20, experienced an alanine aminotransferase flare (grade 3) at week 4 that resolved by week 8 and was accompanied by a significant increase in peripheral HBsAg-specific T cells at week 24. Conclusions In virally suppressed HBeAg-negative patients, checkpoint blockade was well-tolerated and led to HBsAg decline in most patients and sustained HBsAg loss in 1 patient. Lay summary Chronic hepatitis B virus infection (CHB) is characterized by a dysfunctional immune response. In patients with CHB, inhibitory receptors, such as programmed death receptor 1 (PD-1) are overexpressed on T cells, leading to an ineffective immune response in the liver. Herein, we show that the PD-1 inhibitor, nivolumab, is safe and effective for the treatment of virally suppressed patients with CHB. Australian New Zealand Clinical Trials Registry (http://www.anzctr.org.au/) number: ACTRN12615001133527.
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- 2019
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40. Durability of Hepatitis B Surface Antigen Loss With Nucleotide Analogue and Peginterferon Therapy in Patients With Chronic Hepatitis B
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Anna S. Lok, Maria Buti, John F. Flaherty, G. Mani Subramanian, Fabien Zoulim, Anuj Gaggar, Geoffrey Dusheiko, George Y. Wu, Patrick Marcellin, Henry Lik-Yuen Chan, Jenny C. Yang, Stephen Locarnini, Marc G. Ghany, University of Michigan [Ann Arbor], University of Michigan System, Centre de Recherche en Cancérologie de Lyon (UNICANCER/CRCL), Centre Léon Bérard [Lyon]-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Hospices Civils de Lyon (HCL), University College of London [London] (UCL), The Chinese University of Hong Kong [Hong Kong], Vall d'Hebron University Hospital [Barcelona], National Institutes of Health [Bethesda] (NIH), Gilead Sciences, Victorian Infectious Diseases Reference Laboratory, Hôpital Beaujon [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Université Paris Diderot - Paris 7 (UPD7), and Manship, Brigitte
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HBsAg ,medicine.medical_specialty ,Hepatology ,Combination therapy ,business.industry ,virus diseases ,[SDV.CAN]Life Sciences [q-bio]/Cancer ,Original Articles ,Hepatitis b surface antigen ,Gastroenterology ,Virus ,digestive system diseases ,Clinical trial ,Chronic hepatitis ,[SDV.CAN] Life Sciences [q-bio]/Cancer ,Internal medicine ,Medicine ,In patient ,lcsh:Diseases of the digestive system. Gastroenterology ,Original Article ,Seroconversion ,lcsh:RC799-869 ,business - Abstract
International audience; In patients with chronic hepatitis B (CHB), loss of hepatitis B surface antigen (HBsAg) is considered a functional cure. However, HBsAg loss is uncommon with existing therapies, and predictive factors associated with HBsAg seroreversion are unknown. Using pooled data from three phase 3 clinical trials of patients with CHB treated with nucleos(t)ide analogue (NUC) monotherapy or peginterferon (Peg-IFN) ± NUC combination therapy, we conducted a retrospective analysis to characterize patients who achieved sustained HBsAg loss, the predictors of HBsAg seroreversion, and the impact of hepatitis B surface antibody (anti-HBs) seroconversion on durability of HBsAg loss. In these three international trials, 1,381 adults with CHB received either NUC monotherapy for up to 10 years or Peg-IFN-containing regimens for up to 1 year. A total of 55 patients had confirmed HBsAg loss, defined as two or more consecutive negative-qualitative HBsAg results, with a minimum of one repeat result after the end of treatment. Throughout a median of 96 (quartile [Q]1, Q3, 46, 135) weeks follow-up after HBsAg loss, HBsAg loss was durable in 82% (n = 45) of patients, with 10 patients experiencing HBsAg seroreversion. Anti-HBs seroconversion was observed during follow-up in 78% of patients who lost HBsAg and in 60% of those who subsequently seroreverted. In analyzing predictors of HBsAg seroreversion, study treatment was significant, yet anti-HBs seroconversion and treatment duration after initial HBsAg loss were not. Risk of HBsAg seroreversion was observed to be lower if HBsAg loss was sustained through the off-treatment week 24 visit (8/10 seroreversions occurred by posttreatment week 24). Conclusion: HBsAg loss after NUC or Peg-IFN-containing regimens was durable in 82% of patients with CHB. Anti-HBs seroconversion and treatment duration after initial HBsAg loss were not significantly associated with durability of HBsAg loss.
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- 2019
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41. Benzyloxycarbonyl-proline-prolinal (ZPP): Dual complementary roles for neutrophil inhibition
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Brett D. Noerager, J.E. Blalock, Tomasz Szul, Matthew T. Hardison, Xin Xu, Preston E. Bratcher, Liliana Viera, Kristopher R. Genschmer, Derek W Russell, M. Abdul Roda, and Amit Gaggar
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Models, Molecular ,0301 basic medicine ,Chemokine ,Proline ,Neutrophils ,Biophysics ,Pharmacology ,Biochemistry ,Cystic fibrosis ,Article ,03 medical and health sciences ,0302 clinical medicine ,Prolyl endopeptidase ,medicine ,Animals ,Humans ,Receptor ,Molecular Biology ,Inflammation ,chemistry.chemical_classification ,Mice, Inbred BALB C ,Lung ,biology ,Chemistry ,Chemotaxis ,Sputum ,Cell Biology ,medicine.disease ,030104 developmental biology ,medicine.anatomical_structure ,Enzyme ,030220 oncology & carcinogenesis ,biology.protein ,Oligopeptides ,medicine.drug - Abstract
Neutrophil influx and activation contributes to organ damage in several major lung diseases. This inflammatory influx is initiated and propagated by both classical chemokines such as interleukin-8 and by downstream mediators such as the collagen fragment cum neutrophil chemokine Pro-Gly-Pro (PGP), which share use of the ELR + CXC receptor family. Benzyloxycarbonyl-proline-prolinal (ZPP) is known to suppress the PGP pathway via inhibition of prolyl endopeptidase (PE), the terminal enzyme in the generation of PGP from collagen. However, the structural homology of ZPP and PGP suggests that ZPP might also directly affect classical glutamate-leucine-arginine positive (ELR+) CXC chemokine signaling. In this investigation, we confirm that ZPP inhibits PE in vitro, demonstrate that ZPP inhibits both ELR + CXC and PGP-mediated chemotaxis in human and murine neutrophils, abrogates neutrophil influx induced by murine intratracheal challenge with LPS, and attenuates human neutrophil chemotaxis to sputum samples of human subjects with cystic fibrosis. Cumulatively, these data demonstrate that ZPP has dual, complementary inhibitory effects upon neutrophil chemokine/matrikine signaling which make it an attractive compound for clinical study of neutrophil inhibition in conditions (such as cystic fibrosis and chronic obstructive pulmonary disease) which evidence concurrent harmful increases of both chemokine and matrikine signaling.
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- 2019
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42. Differences among cigarette-only smokers compared to dual users of cigarettes and little cigars/cigarillos in the criminal justice population
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Kathleen Hodgin, Karen L. Cropsey, Peter S. Hendricks, Isabel C. Scarinci, Aaron Sellers, Samantha Schiavon, and Amit Gaggar
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Adult ,Male ,Cigar Smoking ,medicine.medical_treatment ,media_common.quotation_subject ,Population ,Ethnic group ,Medicine (miscellaneous) ,Toxicology ,Article ,Cigarette Smoking ,Nicotine ,medicine ,Humans ,education ,media_common ,education.field_of_study ,Smokers ,business.industry ,Prisoners ,Addiction ,Racial Groups ,Age Factors ,Cigarillo ,United States ,Educational attainment ,Psychiatry and Mental health ,Clinical Psychology ,Alabama ,Smoking cessation ,Female ,business ,medicine.drug ,Demography ,Criminal justice - Abstract
Introduction The FDA has restrictions on cigarettes; however, little cigars and cigarillos (LCCs) remain largely absent from these regulations. Due to their low prices and flavoring, many engage in dual use of both LCCs and cigarettes. Dual use is particularly prevalent among low income racial/ethnic minority groups. The purpose of this study was to (U.S. Department of Health and Human Services, 2014) conduct an exploratory examination among cigarette users compared to dual users on smoking characteristics; and (Centers for Disease Control and Prevention, 2016) to examine racial differences (White and Black) among cigarette users compared to dual users. Methods Participants (N = 500) were recruited from community corrections (i.e., parole/probation) and categorized as either cigarette-only (66.4%) or dual users (33.6%) if they used little cigars or cigarillos over a one-year period during a smoking cessation clinical trial. Results Dual users were more likely to be younger, Black, males with lower educational attainment compared to cigarette-only smokers. Smokers with increased nicotine dependence were 17% more likely to be cigarette-only smokers compared to dual users. Racial differences revealed that White/cigarette-only smokers were more likely to report non-menthol use and higher cigarette consumption at the end of treatment compared to Black/cigarette-only or Black/dual users. Conclusions This study contributes to our understanding of dual use among a disenfranchised group of smokers. Overall, dual users were more likely to be younger, Black, and male with lower reported nicotine dependence compared to cigarette-only users. Racial differences revealed that non-menthol smokers as well as smokers with greater cigarettes smoked at the end of treatment were more likely White/cigarette-only smokers.
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- 2019
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43. Optimisation of the use of APRI and FIB-4 to rule out cirrhosis in patients with chronic hepatitis B: results from the SONIC-B study
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Qing Xie, Maria Buti, Hannah Choi, Jidong Jia, Harry L.A. Janssen, Vedran Pavlovic, Stefan Zeuzem, H.L. Chan, Yun-Fan Liaw, Anuj Gaggar, Robert J. de Knegt, Teerha Piratvisuth, Milan J. Sonneveld, Willem P. Brouwer, Cynthia Wat, Bettina E. Hansen, and Gastroenterology & Hepatology
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Adult ,Blood Platelets ,Liver Cirrhosis ,Male ,medicine.medical_specialty ,Cirrhosis ,Biopsy ,Subgroup analysis ,Sensitivity and Specificity ,Severity of Illness Index ,Gastroenterology ,03 medical and health sciences ,Hepatitis B, Chronic ,0302 clinical medicine ,Chronic hepatitis ,SDG 3 - Good Health and Well-being ,Internal medicine ,Severity of illness ,medicine ,Humans ,Multicenter Studies as Topic ,Cutoff ,In patient ,Aspartate Aminotransferases ,Derivation ,Randomized Controlled Trials as Topic ,Hepatology ,business.industry ,Hepatitis B ,medicine.disease ,ROC Curve ,030220 oncology & carcinogenesis ,Female ,030211 gastroenterology & hepatology ,business ,Biomarkers - Abstract
Ruling out the presence of cirrhosis is important for the management of chronic hepatitis B. We aimed to study and optimise the performance of two non-invasive indices for ruling out cirrhosis: the aspartate aminotransferase-platelet ratio index (APRI) and fibrosis score based on four factors (FIB-4).We applied established cutoffs to rule in (APRI2·00; FIB-43·25) or rule out (APRI1·00; FIB-41·45) cirrhosis to data from eight global randomised trials that required baseline biopsy, and identified new cutoffs aiming for a sensitivity for detection of cirrhosis greater than 90% and a negative predictive value (NPV) of greater than 95% in the same dataset. We externally validated the new cutoffs using data from all consecutive biopsied patients from two tertiary referral hospitals in the Netherlands and Canada.In the derivation dataset (n=2926; of whom 1750 were Asian); 340 (12%) individuals had cirrhosis. The validation cohort consisted of 1034 individuals (of whom 575 were Asian), with 155 (15%) individuals with cirrhosis. Application of conventional cutoffs for FIB-4 in the derivation dataset yielded unclassifiable results in 686 (23%) individuals, and 139 (41%) of the 340 patients with cirrhosis were misclassified as having no cirrhosis. Similarly, conventional cutoffs for APRI in the derivation dataset yielded unclassifiable results in 706 (24%) individuals, and 153 (45%) were misclassified as having no cirrhosis. An APRI of 0·45 or less had sensitivity of 91·5%, an NPV of 95·4%, and misclassified 29 (9%) of 340 individuals with cirrhosis in the derivation dataset, but performance was reduced in the validation set (22 [14%] of 155 individuals with cirrhosis misclassified). A FIB-4 score of 0·70 had a sensitivity of 90·9%, an NPV of 96·6%, and misclassified 31 (9%) of individuals with cirrhosis in the derivation dataset. In the validation cohort, the same score gave a sensitivity of 94·2%, an NPV of 97·3%, and misclassified nine (6%) of the individuals with cirrhosis. Subgroup analysis indicated that the new FIB-4 cutoff performed acceptably in all subgroups except for individuals aged 30 years or younger.Conventional cutoffs for APRI and FIB-4 should not be used to guide management of patients with chronic hepatitis B due to high rates of misclassification. A newly identified and externally validated cutoff for FIB-4 (≤0·70) can be used to exclude cirrhosis in patients over 30 years of age.Foundation for Liver and Gastrointestinal Research, Rotterdam, Netherlands.
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- 2019
44. Gene expression profiling of human tissue-resident immune cells: Comparing blood and liver
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Andre Boonstra, Jun Hou, Simon P. Fletcher, Anuj Gaggar, Robert J. de Knegt, Marieke van der Heide-Mulder, Lauke L. Boeijen, Li Li, Gertine W. van Oord, and Gastroenterology & Hepatology
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Adult ,Male ,0301 basic medicine ,Immunology ,System Biology & Immunogenetics ,Cells: Natural Killer ,Brief Conclusive Report ,Tissue/System: Digestive ,Inflammation ,Biology ,Virus ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,Cells: T Lymphocytes ,Gene expression ,medicine ,Humans ,Immunology and Allergy ,Lymphocytes ,RNA, Messenger ,Gene ,Process: Lymphoid Cell Mediated Immunity ,Techniques: Multiparameter FACS ,Gene Expression Profiling ,Process: Gene Regulation ,Cell Biology ,Middle Aged ,Cell sorting ,Hepatitis B ,medicine.disease ,Gene expression profiling ,Tissue/System: Lymphoid ,030104 developmental biology ,Liver ,Process: Host‐Pathogen Interactions ,030220 oncology & carcinogenesis ,Female ,medicine.symptom ,Viral hepatitis ,Signal Transduction - Abstract
In this study, we describe a method to reliably characterize intrahepatic leukocyte populations using flow cytometry and next‐generation RNA sequencing on fresh human liver biopsies. Over the last decades, immune responses of viral hepatitis patients, and of other liver diseases, have been incompletely characterized. Most studies include peripheral blood samples only, foregoing the possibility to investigate the site of inflammation directly. Here, we show that with an optimized protocol that combines cell sorting and RNA sequencing, we can perform a side by side comparison of both intrahepatic and peripheral immune cells. Using core liver biopsies from chronic hepatitis B virus patients, we show that the expression levels of IFN‐stimulated genes and leukocyte‐specific genes are markedly different in the liver compartment as compared to the peripheral blood. These observations emphasize the need to sample the liver directly. The variation of gene expression profiles in these chronic hepatitis B patients was considerable, despite the uniform treatment with nucleotide analogs and absence of liver inflammation in these patients. Finally, we show that this method can provide a detailed characterization of previously undetected liver‐specific effects of novel candidate therapeutic compounds., The use of fluorescence‐activated cell sorting and next generation RNA sequencing to maximize the information yield of studies investigating tissue‐resident leukocytes in human liver.
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- 2019
45. Targeting prolyl endopeptidase with valproic acid as a potential modulator of neutrophilic inflammation.
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Mojtaba Abdul Roda, Mariam Sadik, Amit Gaggar, Matthew T Hardison, Michael J Jablonsky, Saskia Braber, James Edwin Blalock, Frank A Redegeld, Gert Folkerts, and Patricia L Jackson
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Medicine ,Science - Abstract
A novel neutrophil chemoattractant derived from collagen, proline-glycine-proline (PGP), has been recently characterized in chronic obstructive pulmonary disease (COPD). This peptide is derived via the proteolytic activity of matrix metalloproteases (MMP's)-8/9 and PE, enzymes produced by neutrophils and present in COPD serum and sputum. Valproic acid (VPA) is an inhibitor of PE and could possibly have an effect on the severity of chronic inflammation. Here the interaction site of VPA to PE and the resulting effect on the secondary structure of PE is investigated. Also, the potential inhibition of PGP-generation by VPA was examined in vitro and in vivo to improve our understanding of the biological role of VPA. UV-visible, fluorescence spectroscopy, CD and NMR were used to determine kinetic information and structural interactions between VPA and PE. In vitro, PGP generation was significantly inhibited by VPA. In vivo, VPA significantly reduced cigarette-smoke induced neutrophil influx. Investigating the molecular interaction between VPA and PE showed that VPA modified the secondary structure of PE, making substrate binding at the catalytic side of PE impossible. Revealing the molecular interaction VPA to PE may lead to a better understanding of the involvement of PE and PGP in inflammatory conditions. In addition, the model of VPA interaction with PE suggests that PE inhibitors have a great potential to serve as therapeutics in inflammatory disorders.
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- 2014
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46. Factors influencing the measurement of plasma/serum surfactant protein D levels by ELISA.
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Preston E Bratcher and Amit Gaggar
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Medicine ,Science - Abstract
Extensive variations in human surfactant protein D (SP-D) levels in circulation as measured by ELISA exist in the published literature. In order to determine the source of these variations, factors influencing the measurement by ELISA were explored.Peripheral blood from healthy individuals was collected into various vacutainers during the same blood draw. Recombinant SP-D was diluted into different matrices and used for a standard curve. Samples were analyzed by capture ELISA using one of two distinct detection antibodies.The type of matrix had some effects on detection of recombinant SP-D. The type of anticoagulant used and dilution factor had very little effect, except for in plasma collected in EDTA vacutainers. The extent of variation in published values seemed to be due to the ELISA configuration employed, and, in agreement with this, we found that by switching the detection antibody, there was a 50% decrease in the extrapolated SP-D value of serum and plasma samples. Storage of samples resulted in slight changes in measured SP-D levels.The ELISA configuration employed to measure circulating levels of SP-D has a significant effect on the extrapolated values. In both configurations tested, the use of EDTA as a coagulant resulted in inconsistent values, and we, therefore, suggest the avoidance of this anticoagulant when assaying for SP-D by ELISA. While the demonstrated effects of several factors on measurement of SP-D may not account for all the disparities amongst the previous studies, they stress that variations in methodologies for measuring the same protein can result in very inconsistent results.
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- 2014
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47. A whole recombinant yeast-based therapeutic vaccine elicits HBV X, S and Core specific T cells in mice and activates human T cells recognizing epitopes linked to viral clearance.
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Thomas H King, Charles B Kemmler, Zhimin Guo, Derrick Mann, Yingnian Lu, Claire Coeshott, Adam J Gehring, Antonio Bertoletti, Zi Z Ho, William Delaney, Anuj Gaggar, G Mani Subramanian, John G McHutchison, Shikha Shrivastava, Yu-Jin L Lee, Shyamasundaran Kottilil, Donald Bellgrau, Timothy Rodell, and David Apelian
- Subjects
Medicine ,Science - Abstract
Chronic hepatitis B infection (CHB) is characterized by sub-optimal T cell responses to viral antigens. A therapeutic vaccine capable of restoring these immune responses could potentially improve HBsAg seroconversion rates in the setting of direct acting antiviral therapies. A yeast-based immunotherapy (Tarmogen) platform was used to make a vaccine candidate expressing hepatitis B virus (HBV) X, surface (S), and Core antigens (X-S-Core). Murine and human immunogenicity models were used to evaluate the type and magnitude of HBV-Ag specific T cell responses elicited by the vaccine. C57BL/6J, BALB/c, and HLA-A*0201 transgenic mice immunized with yeast expressing X-S-Core showed T cell responses to X, S and Core when evaluated by lymphocyte proliferation assay, ELISpot, intracellular cytokine staining (ICS), or tumor challenge assays. Both CD4+ and CD8+ T cell responses were observed. Human T cells transduced with HBc18-27 and HBs183-91 specific T cell receptors (TCRs) produced interferon gamma (IFNγ following incubation with X-S-Core-pulsed dendritic cells (DCs). Furthermore, stimulation of peripheral blood mononuclear cells (PBMCs) isolated from CHB patients or from HBV vaccine recipients with autologous DCs pulsed with X-S-Core or a related product (S-Core) resulted in pronounced expansions of HBV Ag-specific T cells possessing a cytolytic phenotype. These data indicate that X-S-Core-expressing yeast elicit functional adaptive immune responses and supports the ongoing evaluation of this therapeutic vaccine in patients with CHB to enhance the induction of HBV-specific T cell responses.
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- 2014
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48. Cancer-Associated Fibroblasts and Tumor-Associated Macrophages in Cancer and Cancer Immunotherapy
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Hans Raskov, Adile Orhan, Shruti Gaggar, and Ismail Gögenur
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Tumor microenvironment ,Cancer Research ,Stromal cell ,cancer immunotherapy ,business.industry ,tumor-associated macrophages ,medicine.medical_treatment ,Cell ,Cancer ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,Review ,medicine.disease ,Immune system ,medicine.anatomical_structure ,Cancer immunotherapy ,Stroma ,Oncology ,Cancer research ,Medicine ,Cancer-Associated Fibroblasts ,tumor microenvironment ,business ,cancer-associated fibroblasts ,RC254-282 ,cancer biology - Abstract
Our understanding of the tumor microenvironment (TME), including the interplay between tumor cells, stromal cells, immune cells, and extracellular matrix components, is mandatory for the innovation of new therapeutic approaches in cancer. The cell-cell communication within the TME plays a pivotal role in the evolution and progression of cancer. Cancer-associated fibroblasts (CAF) and tumor-associated macrophages (TAM) are major cell populations in the stroma of all solid tumors and often exert protumorigenic functions; however, the origin and precise functions of CAF and TAM are still incompletely understood. CAF and TAM hold significant potential as therapeutic targets to improve outcomes in oncology when combined with existing therapies. The regulation of CAF/TAM communication and/or their differentiation could be of high impact for improving the future targeted treatment strategies. Nevertheless, there is much scope for research and innovation in this field with regards to the development of novel drugs. In this review, we elaborate on the current knowledge on CAF and TAM in cancer and cancer immunotherapy. Additionally, by focusing on their heterogenous functions in different stages and types of cancer, we explore their role as potential therapeutic targets and highlight certain aspects of their functions that need further research.
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- 2021
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49. HLA-C and KIR permutations influence chronic obstructive pulmonary disease risk
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Amit Gaggar, Michael H. Cho, Kaiyu Yuan, Thi K. Tran-Nguyen, Joseph M. Pilewski, Yingze Zhang, Jianmin Xue, Frank C. Sciurba, Gerard J. Criner, Steven R. Duncan, Young-il Kim, and Takudzwa Mkorombindo
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Male ,Candidate gene ,Pulmonology ,Immunology ,chemical and pharmacologic phenomena ,Human leukocyte antigen ,HLA-C Antigens ,NK cells ,Pathogenesis ,HLA-C ,Pulmonary Disease, Chronic Obstructive ,Receptors, KIR ,medicine ,otorhinolaryngologic diseases ,Cytotoxic T cell ,Humans ,Genetic Predisposition to Disease ,Genetic variation ,Allele ,Aged ,COPD ,Polymorphism, Genetic ,business.industry ,General Medicine ,Middle Aged ,Complex traits ,medicine.disease ,Allotype ,respiratory tract diseases ,Case-Control Studies ,Female ,business ,Research Article - Abstract
A role for hereditary influences in the susceptibility for chronic obstructive pulmonary disease (COPD) is widely recognized. Cytotoxic lymphocytes are implicated in COPD pathogenesis, and functions of these leukocytes are modulated by interactions between their killer-cell immunoglobulin-like receptors (KIR) and human leukocyte antigen (HLA)-Class I molecules on target cells. We hypothesized HLA-Class I and KIR inheritance affect risks for COPD. HLA-Class I alleles and KIR genotypes were defined by candidate gene analyses in multiple cohorts of COPD patients (total n=392) and control smokers with normal spirometry (total n=342). Compared to controls, COPD patients had over-representations of HLA-C*07 and activating KIR2DS1, with under-representations of HLA-C*12. Particular HLA-KIR permutations were synergistic; e.g. the presence of HLA-C*07 + KIR2DS1 + HLA-C12null vs. HLAC*07null + KIR2DS1null + HLA-C12 was associated with COPD, especially among HLA-C1 allotype homozygotes (OR=18.5, 95%CI=3.7-90.9, p
- Published
- 2021
50. Spatial mapping of SARS-CoV-2 and H1N1 lung injury identifies differential transcriptional signatures
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Nitin Arora, Yan Liang, Matthew C. Madison, Rakesh P. Patel, Sarah W Robison, Kathy Ton, Liang Zhang, Paul V. Benson, Nirmal S. Sharma, Camilla Margaroli, and Amit Gaggar
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ARDS ,Medicine (General) ,viruses ,Lung injury ,Lymphocyte Activation ,General Biochemistry, Genetics and Molecular Biology ,Transcriptome ,Influenza A Virus, H1N1 Subtype ,R5-920 ,Report ,Influenza, Human ,Macrophages, Alveolar ,medicine ,Coagulopathy ,Macrophage ,Humans ,skin and connective tissue diseases ,Lung ,Vascular tissue ,Metaplasia ,Respiratory Distress Syndrome ,Spatial Analysis ,business.industry ,SARS-CoV-2 ,spatial transcriptomics ,virus diseases ,COVID-19 ,respiratory system ,medicine.disease ,Squamous metaplasia ,respiratory tract diseases ,medicine.anatomical_structure ,Phenotype ,Alveolar Epithelial Cells ,Immunology ,Autopsy ,H1N1 influenza ,business - Abstract
Severe SARS-CoV-2 infection often leads to development of acute respiratory distress syndrome (ARDS), with profound pulmonary patho-histological changes post-mortem. It is not clear if ARDS from SARS-CoV-2 is similar to that observed in Influenza H1N1, another common viral cause of lung injury. Here, we analyze specific ARDS regions of interest utilizing a spatial transcriptomic platform on autopsy-derived lung tissue from patients with SARS-CoV-2 (n=3), H1N1 (n=3), and a dual infected individual (n=1). Enhanced gene signatures in alveolar epithelium, vascular tissue, and lung macrophages identify not only increased regional coagulopathy, but also increased extracellular remodeling, alternative macrophage activation, and squamous metaplasia of type II pneumocytes in SARS- CoV-2. Both the H1N1 and dual infected transcriptome demonstrated an enhanced antiviral response compared to SARS-CoV-2. Our results uncover regional transcriptional changes related to tissue damage/remodeling, altered cellular phenotype, and vascular injury active in SARS-CoV-2 and presents therapeutic targets for COVID-19 related ARDS., Graphical Abstract, Lung injury can be induced by viral infections, such as H1N1 and SARS-CoV-2 infections. Here, Margaroli et al investigate differential lung responses to both viruses. SARS-CoV-2 induced genes relate to tissue remodeling, while H1N1 profile is skewed towards anti-viral responses.
- Published
- 2021
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