Virologies
Abstract
Nipah virus (NiV), a bat-borne paramyxovirus, results in neurological and respiratory diseases with high mortality in humans and animals. Developing vaccines is crucial against the diseases. Previous few studies focused on fusion (F) protein alone as the immunogen. Numerous NiV strains have been identified, including two representative strains from Malaysia (NiV-M) and Bangladesh (NiV-B), which differ significantly from the other. In this study, an F protein sequence with the potential to prevent different NiV strain infections was designed by bioinformatics analysis after an in-depth study of NiV sequences in GenBank. Then, a chimpanzee adenovirus vector vaccine and a DNA vaccine were developed. High levels of immune responses were detected by AdC68-F, pVAX1-F and a prime-boost strategy (pVAX1-F/AdC68-F) in mice. After high titers of humoral responses were induced, the hamsters were challenged by the lethal NiV-M and NiV-B strains, respectively. It was reassuring that the vaccinated hamsters did not show any clinical signs and survived 21 days after infection with either strain of NiV, and no virus was detected in different tissues either. These results indicated that vaccines provided complete protection against representative strains of NiV infection and had the potential to be developed as a broad-spectrum vaccine for human use.
Authors
Mingqing Lu, Yanfeng Yao, Hang Liu, Xuekai Zhang, Xuejie Li, Yuanhua Liu, Yun Peng, Tong Chen, Yun Sun, Ge Gao, Miaoyu Chen, Jiaxuan Zhao, XiaoYu Zhang, Chunhong Yin, Weiwei Guo, Peipei Yang, Xue Hu, Juhong Rao, Entao Li, Gary Wong, Zhiming Yuan, Sandra Chiu, Chao Shan, Jiaming Lan
Abstract
Optimal lung repair and regeneration is essential for recovery from viral infections including influenza A virus (IAV). We have previously demonstrated that acute inflammation and mortality induced by IAV is under circadian control. However, it is not known if the influence of the circadian clock persists beyond the acute outcomes. Here, we utilize the UK Biobank to demonstrate an association between poor circadian rhythms and morbidity from lower respiratory tract infections including the need for hospitalization and post-discharge mortality; this persists even after adjusting for common confounding factors. Further, we use a combination of lung organoid assays, single cell RNA sequencing (Sc-seq) and IAV infection in different models of clock disruption to investigate the role of the circadian clock in lung repair and regeneration. We show for the first time that lung organoids have a functional circadian clock, and the disruption of this clock impairs regenerative capacity. Finally, we find that the circadian clock acts through distinct pathways in mediating lung regeneration- in tracheal cells via the Wnt/β-catenin pathway and through IL1β in alveolar epithelial cells. We speculate, that adding a circadian dimension to the critical process of lung repair and regeneration will lead to novel therapies and improve outcomes.
Authors
Amruta Naik, Kaitlyn M. Forrest, Oindrila Paul, Yasmine Issah, Utham Kashyap Valekunja, Soon Yew Tang, Akhilesh B. Reddy, Elizabeth J. Hennessy, Thomas G. Brooks, Fatima N. Chaudhry, Apoorva Babu, Michael P. Morley, Jarod A. Zepp, Gregory R. Grant, Garret FitzGerald, Amita Sehgal, G. Scott Worthen, David B. Frank, Edward E. Morrisey, Shaon Sengupta
Abstract
Antiviral immunity often requires CD8+ cytotoxic T lymphocytes (CTLs) that actively migrate and search for virus-infected targets. Regulatory T cells (Tregs) have been shown to suppress CTL responses, but it is not known whether this is also mediated by effects on CTL motility. Here, we used intravital 2-photon microscopy in the Friend retrovirus (FV) mouse model to define the impact of Tregs on CTL motility throughout the course of acute infection. Virus-specific CTLs were very motile and had frequent short contacts with target cells at their peak cytotoxic activity. However, when Tregs were activated and expanded in late-acute FV infection, CTLs became significantly less motile and contacts with target cells were prolonged. This phenotype was associated with development of functional CTL exhaustion. Tregs had direct contacts with CTLs in vivo and, importantly, their experimental depletion restored CTL motility. Our findings identify an effect of Tregs on CTL motility as part of their mechanism of functional impairment in chronic viral infections. Future studies must address the underlying molecular mechanisms.
Authors
Daniela Mittermüller, Lucas Otto, Zoë Long, Andreas Kraus, Alexander Beer, Anja Hasenberg, Gennadiy Zelinskyy, Jaana Westmeier, Kim J. Hasenkrug, Ulf Dittmer, Matthias Gunzer
Abstract
Influenza A virus (IAV) infection is commonly complicated by secondary bacterial infections, leading to increased morbidity and mortality. Our recent work demonstrates that IAV disrupts airway homeostasis, leading to airway pathophysiology resembling cystic fibrosis disease through diminished cystic fibrosis transmembrane conductance regulator (CFTR) function. Here, we use human airway organotypic cultures to investigate how IAV alters the airway microenvironment to increase susceptibility to secondary infection with Streptococcus pneumoniae (Spn). We observed that IAV-induced CFTR dysfunction and airway surface liquid acidification is central to increasing susceptibility to Spn. Additionally, we observed that IAV induced profound transcriptional changes in the airway epithelium and proteomic changes in the airway surface liquid in both CFTR dependent and independent manners. These changes correspond to multiple diminished host defense pathways and altered airway epithelial function. Collectively, these findings highlight both the importance of CFTR function during infectious challenge and demonstrate a central role for the lung epithelium in secondary bacterial infections following IAV.
Authors
Erin Y. Earnhardt, Jennifer L. Tipper, Adonis D'Mello, Ming-Yuan Jian, Elijah S. Conway, James A. Mobley, Carlos J. Orihuela, Hervé Tettelin, Kevin S. Harrod
Abstract
Respiratory syncytial virus (RSV) infection causes significant morbidity and mortality in infants, immunocompromised, and older individuals. There is an urgent need for effective antivirals and vaccines for high risk individuals. We used two complementary in vivo models to analyze RSV-associated human lung pathology and human immune correlates of protection. RSV infection resulted in widespread human lung epithelial damage, a pro-inflammatory innate immune response, and elicited a natural adaptive human immune response that conferred protective immunity. We demonstrated a key role for human T cells in controlling RSV infection. Specifically, primed human CD8+ T cells or CD4+ T cells effectively and independently control RSV replication in human lung tissue in the absence of an RSV-specific antibody response. These preclinical data support the development of RSV vaccines which also elicit effective T cell responses to improve RSV vaccine efficacy.
Authors
Chandrav De, Raymond J. Pickles, Wenbo Yao, Baolin Liao, Allison E. Boone, Mingyu Choi, Diana M. Battaglia, Frederic B. Askin, Jason K. Whitmire, Guido Silvestri, J. Victor Garcia, Angela Wahl
Abstract
Hepatitis delta virus (HDV), a satellite virus of HBV, is regarded as the most severe type of hepatitis virus because of the substantial morbidity and mortality. The IFN system is the first line of defense against viral infections and an essential element of antiviral immunity; however, the role of the hepatic IFN system in controlling HBV-HDV infection remains poorly understood. Herein, we showed that HDV infection of human hepatocytes induced a potent and persistent activation of the IFN system whereas HBV was inert in triggering hepatic antiviral response. Moreover, we demonstrated that HDV-induced constitutive activation of the hepatic IFN system resulted in a potent suppression of HBV while modestly inhibiting HDV. Thus, these pathogens are equipped with distinctive immunogenicity and varying sensitivity to the antiviral effectors of IFN, leading to the establishment of a paradoxical mode of viral interference wherein HDV, the superinfectant, outcompetes HBV, the primary pathogen. Furthermore, our study revealed that HDV-induced constitutive IFN system activation led to a state of IFN refractoriness, rendering therapeutic IFNs ineffective. The present study provides potentially novel insights into the role of the hepatic IFN system in regulating HBV-HDV infection dynamics and its therapeutic implications through elucidating the molecular basis underlying the inefficacy of IFN-based antiviral strategies against HBV-HDV infection.
Authors
Takeshi Chida, Yuji Ishida, Sho Morioka, Go Sugahara, Christine Han, Bill Lam, Chihiro Yamasaki, Remi Sugahara, Meng Li, Yasuhito Tanaka, T. Jake Liang, Chise Tateno, Takeshi Saito
Abstract
Human T lymphotropic virus type 1–assoicated (HTLV-1–associated) myelopathy/tropical spastic paraparesis (HAM/TSP) is a neuroinflammatory disease caused by the persistent proliferation of HTLV-1–infected T cells. Here, we performed a T cell receptor (TCR) repertoire analysis focused on HTLV-1–infected cells to identify and track the infected T cell clones that are preserved in patients with HAM/TSP and migrate to the CNS. TCRβ repertoire analysis revealed higher clonal expansion in HTLV-1–infected cells compared with noninfected cells from patients with HAM/TSP and asymptomatic carriers (ACs). TCR clonality in HTLV-1–infected cells was similar in patients with HAM/TSP and ACs. Longitudinal analysis showed that the TCR repertoire signature in HTLV-1–infected cells remained stable, and highly expanded infected clones were preserved within each patient with HAM/TSP over years. Expanded HTLV-1–infected clones revealed different distributions between cerebrospinal fluid (CSF) and peripheral blood and were enriched in the CSF of patients with HAM/TSP. Cluster analysis showed similarity in TCRβ sequences in HTLV-1–infected cells, suggesting that they proliferate after common antigen stimulation. Our results indicate that exploring TCR repertoires of HTLV-1–infected cells can elucidate individual clonal dynamics and identify potential pathogenic clones expanded in the CNS.
Authors
Satoshi Nozuma, Eiji Matsuura, Masakazu Tanaka, Daisuke Kodama, Toshio Matsuzaki, Akiko Yoshimura, Yusuke Sakiyama, Shingo Nakahata, Kazuhiro Morishita, Yoshimi Enose-Akahata, Steven Jacoboson, Ryuji Kubota, Hiroshi Takashima
Abstract
Rhesus cytomegalovirus (RhCMV)-based vaccine vectors induce immune responses that protect ~60% of rhesus macaques (RMs) from SIVmac239 challenge. This efficacy depends on induction of effector memory (EM)-biased CD8+ T cells recognizing SIV peptides presented by major histocompatibility complex (MHC)-E instead of MHC-Ia. The phenotype, durability, and efficacy of RhCMV/SIV-elicited cellular immune responses were maintained when vector spread was severely reduced by deleting the anti-host intrinsic immunity factor pp71. Here, we examined the impact of an even more stringent attenuation strategy on vector-induced immune protection against SIV. Fusion of the FK506-binding protein (FKBP) degradation domain to Rh108, the orthologue of the essential human CMV (HCMV) late gene transcription factor UL79, generated RhCMV/SIV vectors that conditionally replicate only when the FK506-analog Shield-1 is present. Despite lacking in vivo dissemination and reduced innate and B cell responses to vaccination, Rh108-deficient 68-1 RhCMV/SIV vectors elicited high frequency, durable, EM-biased, SIV-specific T cell responses in RhCMV-seropositive RM at doses of ≥106 PFU. Strikingly, elicited CD8+ T cells exclusively targeted MHC-Ia-restricted epitopes and failed to protect against SIVmac239 challenge. Thus, Rh108-dependent late gene expression is required for both induction of MHC-E-restricted T cells and protection against SIV.
Authors
Scott G. Hansen, Jennie L. Womack, Wilma Perez, Kimberli A. Schmidt, Emily Marshall, Ravi F. Iyer, Hillary Cleveland-Rubeor, Claire E. Otero, Husam Taher, Nathan H. Vande Burgt, Richard Barfield, Kurt T. Randall, David Morrow, Colette M. Hughes, Andrea N. Selseth, Roxanne M. Gilbride, Julia C. Ford, Patrizia Caposio, Alice Tarantal, Cliburn Chan, Daniel Malouli, Peter A. Barry, Sallie R. Permar, Louis J. Picker, Klaus Frueh
Abstract
Type 1 diabetes (T1D) is an autoimmune disease resulting in pancreatic β-cell destruction. Coxsackievirus B3 (CVB3) infection and melanoma differentiation-associated protein 5 (MDA5)-dependent antiviral responses are linked with T1D development. Mutations within IFIH1, encoding for MDA5, are correlated with T1D susceptibility, but how these mutations contribute to T1D remains unclear. Utilizing non-obese diabetic (NOD) mice lacking Ifih1 expression (KO) or containing an in-frame deletion within the ATPase site of the helicase 1 domain of MDA5 (ΔHel1), we tested the hypothesis that partial or complete loss-of-function mutations in MDA5 would delay T1D by impairing proinflammatory pancreatic macrophage and T cell responses. Spontaneous T1D developed in female NOD and KO mice similarly, but was significantly delayed in ΔHel1 mice that may be partly due to a concomitant increase in myeloid-derived suppressor cells. Interestingly, KO male mice had increased spontaneous T1D compared to NOD mice. While NOD and KO mice developed CVB3-accelerated T1D, ΔHel1 mice were protected partly due to decreased type I interferons, pancreatic-infiltrating TNF+ macrophages, IFN-γ+ CD4+ T cells, and perforin+ CD8+ T cells. Furthermore, ΔHel1 MDA5 protein had reduced ATP hydrolysis compared to wild-type MDA5. Our results suggest dampened MDA5 function delays T1D, yet loss of MDA5 promotes T1D.
Authors
Samuel I. Blum, Jared P. Taylor, Jessie M. Barra, Ashley R. Burg, Qiao Shang, Shihong Qiu, Oren Shechter, Aleah R. Hayes, Todd J. Green, Aron M. Geurts, Yi-Guang Chen, Hubert M. Tse
Abstract
In spite of the rollout of oral pre-exposure prophylaxis (PrEP), the rate of new HIV infections remains a major health crisis. In the United States, new infections occur predominantly in men having sex with men (MSM) in rural settings where access to PrEP can be limited. As an alternative congruent with MSM sexual behavior, we have optimized and tested tenofovir (TFV) and analog-based iso-osmolar and hypo-osmolar (HOsm) rectal douches for efficacy against rectal simian/human immunodeficiency virus (SHIV) infection of macaques. Single TFV HOsm high-dose douches achieved peak plasma TFV levels similar to daily oral PrEP, while other formulations yielded lower concentrations. Rectal tissue TFV-diphosphate (TFV-DP) concentrations at the portal of virus entry, however, were markedly higher after HOsm douching than daily oral PrEP. Repeated douches led to significantly higher plasma TFV and higher TFV-DP concentrations in rectal tissue at 24 hours compared with single douches, without detectable mucosal or systemic toxicity. Using stringent repeated intrarectal SHIV exposures, single HOsm high-dose douches delivered greater protection from virus acquisition for more than 24 hours compared with oral PrEP. Our results demonstrate a rapid delivery of protective TFV doses to the rectal portal of virus entry as a potential low-cost and safe PrEP alternative.
Authors
Peng Xiao, Sanjeev Gumber, Mark A. Marzinke, Thuy Hoang, Rohan Myers, Abhijit A. Date, Justin Hanes, Laura M. Ensign, Lin Wang, Lisa C. Rohan, Richard Cone, Edward J. Fuchs, Craig W. Hendrix, Francois Villinger
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