Virology
Abstract
Virus-induced respiratory tract infections are a major health burden in childhood, and available treatments are supportive rather than disease modifying. Rhinoviruses (RVs), the cause of approximately 80% of common colds, are detected in nearly half of all infants with bronchiolitis and the majority of children with an asthma exacerbation. Bronchiolitis in early life is a strong risk factor for the development of asthma. Here, we found that RV infection induced the expression of miRNA 122 (miR-122) in mouse lungs and in human airway epithelial cells. In vivo inhibition specifically in the lung reduced neutrophilic inflammation and CXCL2 expression, boosted innate IFN responses, and ameliorated airway hyperreactivity in the absence and in the presence of allergic lung inflammation. Inhibition of miR-122 in the lung increased the levels of suppressor of cytokine signaling 1 (SOCS1), which is an in vitro–validated target of miR-122. Importantly, gene silencing of SOCS1 in vivo completely reversed the protective effects of miR-122 inhibition on RV-induced lung disease. Higher miR-122 expression in nasopharyngeal aspirates was associated with a longer time on oxygen therapy and a higher rate of treatment failure in 87 infants hospitalized with moderately severe bronchiolitis. These results suggest that miR-122 promotes RV-induced lung disease via suppression of its target SOCS1 in vivo. Higher miR-122 expression was associated with worse clinical outcomes, highlighting the potential use of anti-miR-122 oligonucleotides, successfully trialed for treatment of hepatitis C, as potential therapeutics for RV-induced bronchiolitis and asthma exacerbations.
Authors
Adam M. Collison, Leon A. Sokulsky, Elizabeth Kepreotes, Ana Pereira de Siqueira, Matthew Morten, Michael R. Edwards, Ross P. Walton, Nathan W. Bartlett, Ming Yang, Thi Hiep Nguyen, Sebastian L. Johnston, Paul S. Foster, Joerg Mattes
Abstract
HIV-1 is capable of integrating its genome into that of its host cell. We examined the influence of the activation state of CD4+ T-cells, the effect of antiretroviral therapy (ART), and the clinical stage of HIV-1 infection on HIV-1 integration site features and selection. HIV-1 integration sites were sequenced from longitudinally sampled resting and activated CD4+ T-cells from 12 HIV-1 infected individuals. In total, 589 unique HIV-1 integration sites were analyzed: 147, 391, and 51 during primary, chronic, and late presentation of HIV-1 infection, respectively. As early as during primary HIV-1 infection and independent of the activation state of CD4+ T-cells collected on and off ART, HIV-1 integration sites were preferentially detected in recurrent integration genes (RIGs), genes associated with clonal expansion of latently HIV-1 infected CD4+ T-cells, cancer related genes, and highly expressed genes. The preference for cancer related genes was more pronounced at late stages of HIV-1 infection. Host genomic features of HIV-1 integration site selection remained stable during the course of HIV-1 infection in both resting and activated CD4+ T-cells. In summary, characteristic HIV-1 integration site features are pre-established as early as during primary HIV-1 infection and are found in both resting and activated CD4+ T-cells.
Authors
Yik Lim Kok, Valentina Vongrad, Sandra E. Chaudron, Mohaned Shilaih, Christine Leemann, Kathrin Neumann, Katharina Kusejko, Francesca Di Giallonardo, Herbert Kuster, Dominique L. Braun, Roger D. Kouyos, Huldrych F. Günthard, Karin J. Metzner
Abstract
In search of new prognostic markers, many mutation analyses of the HBV genome were performed. However, the Kozak sequence preceding precore was covered only infrequently in these analyses. In this study, HBV core promoter/precore region was sequenced in serum samples of European inactive HBV carriers (n=560). Quadruple mutation GCAC1809-1812TTCT was found with a high prevalence of 42% in the Kozak sequence preceding precore among all HBV genotypes. GCAC1809-1812TTCT was strongly associated with coexistence of basal core promoter (BCP) double mutation A1762T/G1764A and lower HBV DNA levels (p<0.0001). In vitro GCAC1809-1812TTCT leads to drastically diminished synthesis of pregenomic(pg)RNA, precore mRNA, core, HBsAg and HBeAg. Calculation of the pgRNA secondary structure suggests a destabilization of the pgRNA structure by A1762T/G1764A that is compensated by GCAC1809-1812TTCT. In 125 patients with HBV-related cirrhosis, GCAC1809-1812TTCT was not detected. While a strong association of GCAC1809-1812TTCT with inactive carrier status (p<0.0001) was observed, BCP double mutation was strongly correlated with cirrhosis (p<0.0001), but this was only observed in absence of GCAC1809-1812TTCT. In conclusion, our data reveal that GCAC1809-1812TTCT is highly prevalent in inactive carriers, and acts as a compensatory mutation for BCP double mutation. GCAC1809-1812TTCT seems to be a biomarker of good prognosis in HBV infection.
Authors
Kai-Henrik Peiffer, Catrina Spengler, Michael Basic, Bingfu Jiang, Lisa Kuhnhenn, Wiebke Obermann, Tobias Zahn, Mirco Glitscher, Alessandro Loglio, Floriana Facchetti, Gert Carra, Alica Kubesch, Johannes Vermehren, Viola Knop, Christiana Graf, Julia Dietz, Fabian Finkelmeier, Eva Herrmann, Jonel Trebicka, Arnold Grünweller, Stefan Zeuzem, Christoph Sarrazin, Pietro Lampertico, Eberhard Hildt
Abstract
The challenge of discovering a completely new human tumor virus of unknown phylogeny or sequence depends on detecting viral molecules and differentiating them from host molecules in the virus-associated neoplasm. We developed differential peptide subtraction (DPS) using differential mass-spectrometry (dMS) followed by targeted analysis to facilitate this discovery. We validated this approach by analyzing Merkel cell carcinoma (MCC), an aggressive human neoplasm, in which ~80% of cases are caused by the human Merkel cell polyomavirus (MCV). Approximately 20% of MCC have a high mutational burden and are negative for MCV, but are microscopically indistinguishable from virus positive cases. Using 23 (12 MCV positive, 11 MCV negative) formalin-fixed MCC, DPS identified both viral and human biomarkers (MCV Large T antigen, CDKN2AIP, SERPINB5 and TRIM29) that discriminates MCV positive and negative MCC. Statistical analysis of 498,131 dMS features not matching the human proteome by DPS revealed 562 (0.11%) to be up-regulated in virus-infected samples. Remarkably, four (20%) of the top 20 candidate MS spectra originated from MCV T oncoprotein peptides and confirmed by reverse translation degenerate oligonucleotide sequencing. DPS is a robust proteomic approach to identify novel viral sequences in infectious tumors when nucleic acid-based methods are not feasible.
Authors
Tuna Toptan, Pamela S. Cantrell, Xuemei Zeng, Yang Liu, Mai Sun, Nathan A. Yates, Yuan Chang, Patrick S. Moore
Abstract
Primary varicella-zoster virus (VZV) infection in adults is often complicated by severe pneumonia, which is difficult to treat and associated with high morbidity and mortality. Here, the simian varicella virus (SVV) nonhuman primate (NHP) model was used to investigate the pathogenesis of varicella pneumonia. SVV infection resulted in transient fever, viremia and robust virus replication in alveolar pneumocytes and bronchus-associated lymphoid tissue. Clearance of infectious virus from lungs coincided with robust innate immune responses, leading to recruitment of inflammatory cells, mainly neutrophils and lymphocytes, and finally severe acute lung injury. SVV infection caused neutrophil activation and formation of neutrophil extracellular traps (NETs) in vitro and in vivo. Notably, NETs were also detected in lung and blood specimens of varicella pneumonia patients. Lung pathology in the SVV NHP model was associated with dysregulated expression of alveolar epithelial cell tight junction proteins (claudin-2, claudin-10 and claudin-18) and alveolar endothelial adherens junction protein VE-cadherin. Importantly, factors released by activated neutrophils, including NETs, were sufficient to reduce claudin-18 and VE-cadherin expression in NHP lung slice cultures. Collectively, the data indicate that local inflammatory responses involving activated neutrophils contribute to impaired alveolar epithelial/endothelial barrier integrity in varicella pneumonia and possibly other virus-induced acute lung injuries.
Authors
Werner J.D. Ouwendijk, Henk Jan van den Ham, Mark W. Delany, Jeroen J.A. van Kampen, Gijsbert P. van Nierop, Tamana Mehraban, Fatiha Zaaraoui-Boutahar, Wilfred F.J. van IJcken, Judith M.A. van den Brand, Rory D. De Vries, Arno C. Andeweg, Georges M.G.M. Verjans
Abstract
A complete understanding of human immune responses to Ebola virus infection is limited by the availability of specimens and the requirement for biosafety level 4 (BSL-4) containment. In an effort to bridge this gap, we evaluated cryopreserved PBMCs from 4 patients who survived Ebola virus disease (EVD) using an established mass cytometry antibody panel to characterize various cell populations during both the acute and convalescent phases. Acute loss of nonclassical monocytes and myeloid DCs, especially CD1c+ DCs, was noted. Classical monocyte proliferation and CD38 upregulation on plasmacytoid DCs coincided with declining viral load. Unsupervised analysis of cell abundance demonstrated acute declines in monocytic, NK, and T cell populations, but some populations, many of myeloid origin, increased in abundance during the acute phase, suggesting emergency hematopoiesis. Despite cell losses during the acute phase, upregulation of Ki-67 correlated with recovery of cell populations over time. These data provide insights into the human immune response during EVD.
Authors
Anita K. McElroy, Rama S. Akondy, David R. Mcllwain, Han Chen, Zach Bjornson-Hooper, Nilanjan Mukherjee, Aneesh K. Mehta, Garry Nolan, Stuart T. Nichol, Christina F. Spiropoulou
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of human coronavirus disease 2019 (COVID-19), emerged in Wuhan, China in December 2019. The virus rapidly spread globally, resulting in a public-health crisis including more than 3.1 million cases and 224,000 deaths as of May 1, 2020. Here, we describe the identification and evaluation of commercially available reagents and assays for the molecular detection of SARS-CoV-2 in infected formalin fixed paraffin embedded (FFPE) cell pellets. We identified a suitable rabbit polyclonal anti-SARS-CoV spike protein antibody and a mouse monoclonal anti-SARS-CoV nucleocapsid protein (NP) antibody for cross detection of the respective SARS-CoV-2 proteins by immunohistochemistry (IHC) and immunofluorescence assay (IFA). Next, we established RNAscope in situ hybridization (ISH) to detect SARS-CoV-2 RNA. Furthermore, we established a multiplex fluorescence ISH (mFISH) to detect positive-sense SARS-CoV-2 RNA and negative-sense SARS-CoV-2 RNA (a replicative intermediate indicating viral replication). Finally, we developed a dual staining assay using IHC and ISH to detect SARS-CoV-2 antigen and RNA in the same FFPE section. These reagents and assays will accelerate COVID-19 pathogenesis studies in humans and in COVID-19 animal models.
Authors
Jun Liu, April M. Babka, Brian J. Kearney, Sheli R. Radoshitzky, Jens H. Kuhn, Xiankun Zeng
Abstract
Plasma viral load (VL) and CD4+ T-cell count are widely used as biomarkers of HIV-1 replication, pathogenesis, and response to antiretroviral therapy (ART). However, the clinical potential of cell-associated (CA) HIV-1 molecular markers is much less understood. Here, we measured CA HIV-1 RNA and DNA in HIV-infected individuals treated with temporary ART initiated during primary HIV-1 infection. We demonstrate significant predictive value of CA RNA for: (a) the virological and immunological response to early ART, (b) the magnitude and time to viral rebound after discontinuation of early ART, and (c) the disease progression in the absence of treatment. Remarkably, when adjusted for CA RNA, plasma VL no longer appeared as an independent predictor of any clinical endpoint in this cohort. The potential of CA RNA as an HIV-1 clinical marker, in particular as a predictive biomarker of virological control after stopping ART, should be explored in the context of HIV-1 curative interventions.
Authors
Alexander O. Pasternak, Marlous L. Grijsen, Ferdinand W. Wit, Margreet Bakker, Suzanne Jurriaans, Jan M. Prins, Ben Berkhout
Abstract
Recovery from measles results in life-long protective immunity. To understand induction of long-term immunity, rhesus macaques were studied for six months after infection with WT measles virus (MeV). Infection caused viremia and rash with clearance of infectious virus by 14 days. MeV RNA persisted in PBMCs for 30-90 days and in lymphoid tissue for 6 months most often in B cells but was rarely detected in BM. Antibody with neutralizing activity and binding specificity for MeV nucleocapsid (N), hemagglutinin (H) and fusion proteins appeared with the rash and avidity matured over 3-4 months. Lymph nodes had increasing numbers of MeV-specific antibody-secreting cells (ASCs) and germinal centers with late hyalinization. ASCs appeared in circulation with the rash and continued to appear along with peripheral Tfh cells for the study duration. ASCs in lymph nodes and PBMCs produced antibody to both H and N, with more H-specific ASCs in BM. From 14-21 days 20-100-fold more total ASCs than MeV-specific ASCs appeared in circulation suggesting mobilization of pre-existing ASCs. Therefore, persistence of MeV RNA in lymphoid tissue was accompanied by continued germinal center formation, ASC production, avidity maturation and accumulation of H-specific ASCs in BM to sustain neutralizing antibody and protective immunity.
Authors
Ashley N. Nelson, Wen-Hsuan W. Lin, Rupak Shivakoti, Nicole E. Putnam, Lisa M. Mangus, Robert J. Adams, Debra Hauer, Victoria K. Baxter, Diane E. Griffin
Abstract
To investigate the nationwide severe fever with thrombocytopenia syndrome virus (SFTSV) infection status, we isolated SFTSVs from severe fever with thrombocytopenia syndrome (SFTS)-suspected patients in 207 hospitals throughout South Korea between 2013 and April of 2017. A total of 116 SFTSVs were isolated from 3,137 SFTS-suspected patients with an overall 21.6% case fatality rate. Genetic characterization revealed that at least six genotypes of SFTSVs are co-circulating in South Korea with multiple reassortments among them. Of these, the genotype B-2 strains were the most prevalent (n = 48, 36.1%) followed by the A and F genotypes. Clinical and epidemiologic investigations revealed that genotype B strains were associated with the highest case-fatality rate (34.8%, 32/92), while genotype A caused only one fatality out of ten patients. Further, ferret infection studies demonstrated varied clinical manifestations and case mortality rates of different strains of SFTSV, which suggests this virus could exhibit genotype-dependent pathogenicity.Keywords: severe fever with thrombocytopenia syndrome virus (SFTSV), clinical manifestations, genotypes, pathogenesis
Authors
Seok-Min Yun, Su-Jin Park, Young-Il Kim, Sun-Whan Park, Min-Ah Yu, Hyeok-Il Kwon, Eun-Ha Kim, Kwang-Min Yu, Hye Won Jeong, Jungsang Ryou, Won-Ja Lee, Youngmee Jee, Joo-Yeon Lee, Young Ki Choi
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