scholarly journals Genetic variation in chromosome Y regulates susceptibility to influenza A virus infection

2017 ◽  
Vol 114 (13) ◽  
pp. 3491-3496 ◽  
Author(s):  
Dimitry N. Krementsov ◽  
Laure K. Case ◽  
Oliver Dienz ◽  
Abbas Raza ◽  
Qian Fang ◽  
...  

Males of many species, ranging from humans to insects, are more susceptible than females to parasitic, fungal, bacterial, and viral infections. One mechanism that has been proposed to account for this difference is the immunocompetence handicap model, which posits that the greater infectious disease burden in males is due to testosterone, which drives the development of secondary male sex characteristics at the expense of suppressing immunity. However, emerging data suggest that cell-intrinsic (chromosome X and Y) sex-specific factors also may contribute to the sex differences in infectious disease burden. Using a murine model of influenza A virus (IAV) infection and a panel of chromosome Y (ChrY) consomic strains on the C57BL/6J background, we present data showing that genetic variation in ChrY influences IAV pathogenesis in males. Specific ChrY variants increase susceptibility to IAV in males and augment pathogenic immune responses in the lung, including activation of proinflammatory IL-17–producing γδ T cells, without affecting viral replication. In addition, susceptibility to IAV segregates independent of copy number variation in multicopy ChrY gene families that influence susceptibility to other immunopathological phenotypes, including survival after infection with coxsackievirus B3. These results demonstrate a critical role for genetic variation in ChrY in regulating susceptibility to infectious disease.

2021 ◽  
Vol 13 (583) ◽  
pp. eabe5449
Author(s):  
Nicole Darricarrère ◽  
Yu Qiu ◽  
Masaru Kanekiyo ◽  
Adrian Creanga ◽  
Rebecca A. Gillespie ◽  
...  

Seasonal influenza vaccines confer protection against specific viral strains but have restricted breadth that limits their protective efficacy. The H1 and H3 subtypes of influenza A virus cause most of the seasonal epidemics observed in humans and are the major drivers of influenza A virus–associated mortality. The consequences of pandemic spread of COVID-19 underscore the public health importance of prospective vaccine development. Here, we show that headless hemagglutinin (HA) stabilized-stem immunogens presented on ferritin nanoparticles elicit broadly neutralizing antibody (bnAb) responses to diverse H1 and H3 viruses in nonhuman primates (NHPs) when delivered with a squalene-based oil-in-water emulsion adjuvant, AF03. The neutralization potency and breadth of antibodies isolated from NHPs were comparable to human bnAbs and extended to mismatched heterosubtypic influenza viruses. Although NHPs lack the immunoglobulin germline VH1-69 residues associated with the most prevalent human stem-directed bnAbs, other gene families compensated to generate bnAbs. Isolation and structural analyses of vaccine-induced bnAbs revealed extensive interaction with the fusion peptide on the HA stem, which is essential for viral entry. Antibodies elicited by these headless HA stabilized-stem vaccines neutralized diverse H1 and H3 influenza viruses and shared a mode of recognition analogous to human bnAbs, suggesting that these vaccines have the potential to confer broadly protective immunity against diverse viruses responsible for seasonal and pandemic influenza infections in humans.


2021 ◽  
Author(s):  
Ee-Hong Tam ◽  
Yen-Chin Liu ◽  
Chian-Huey Woung ◽  
Helene Minyi Liu ◽  
Guan-Hong Wu ◽  
...  

The NS1 protein of the influenza A virus plays a critical role in regulating several biological processes in cells, including the type I interferon (IFN) response. We previously profiled the cellular factors that interact with the NS1 protein of influenza A virus and found that the NS1 protein interacts with proteins involved in RNA splicing/processing, cell cycle regulation, and protein targeting processes, including 14-3-3ε. Since 14-3-3ε plays an important role in RIG-I translocation to MAVS to activate type I IFN expression, the interaction of the NS1 and 14-3-3ε proteins may prevent the RIG-I-mediated IFN response. In this study, we confirmed that the 14-3-3ε protein interacts with the N-terminal domain of the NS1 protein and that the NS1 protein inhibits RIG-I-mediated IFN-β promoter activation in 14-3-3ε-overexpressing cells. In addition, our results showed that knocking down 14-3-3ε can reduce IFN-β expression elicited by influenza A virus and enhance viral replication. Furthermore, we found that threonine in the 49 th amino acid position of the NS1 protein plays a role in the interaction with 14-3-3ε. Influenza A virus expressing C-terminus-truncated NS1 with T49A mutation dramatically increases IFN-β mRNA in infected cells and causes slower replication than that of virus without the T-to-A mutation. Collectively, this study demonstrates that 14-3-3ε is involved in influenza A virus-initiated IFN-β expression and that the interaction of the NS1 protein and 14-3-3ε may be one of the mechanisms for inhibiting type I IFN activation during influenza A virus infection. IMPORTANCE Influenza A virus is an important human pathogen causing severe respiratory disease. The virus has evolved several strategies to dysregulate the innate immune response and facilitate its replication. We demonstrate that the NS1 protein of influenza A virus interacts with the cellular chaperone protein 14-3-3ε, which plays a critical role in RIG-I translocation that induces type I IFN expression, and that NS1 protein prevents RIG-I translocation to mitochondrial membrane. The interaction site for 14-3-3ε is the RNA-binding domain (RBD) of the NS1 protein. Therefore, this research elucidates a novel mechanism by which the NS1 RBD mediates IFN-β suppression to facilitate influenza A viral replication. Additionally, the findings reveal the antiviral role of 14-3-3ε during influenza A virus infection.


2016 ◽  
Vol 113 (42) ◽  
pp. 11931-11936 ◽  
Author(s):  
Wenqian He ◽  
Gene S. Tan ◽  
Caitlin E. Mullarkey ◽  
Amanda J. Lee ◽  
Mannie Man Wai Lam ◽  
...  

The generation of strain-specific neutralizing antibodies against influenza A virus is known to confer potent protection against homologous infections. The majority of these antibodies bind to the hemagglutinin (HA) head domain and function by blocking the receptor binding site, preventing infection of host cells. Recently, elicitation of broadly neutralizing antibodies which target the conserved HA stalk domain has become a promising “universal” influenza virus vaccine strategy. The ability of these antibodies to elicit Fc-dependent effector functions has emerged as an important mechanism through which protection is achieved in vivo. However, the way in which Fc-dependent effector functions are regulated by polyclonal influenza virus-binding antibody mixtures in vivo has never been defined. Here, we demonstrate that interactions among viral glycoprotein-binding antibodies of varying specificities regulate the magnitude of antibody-dependent cell-mediated cytotoxicity induction. We show that the mechanism responsible for this phenotype relies upon competition for binding to HA on the surface of infected cells and virus particles. Nonneutralizing antibodies were poor inducers and did not inhibit antibody-dependent cell-mediated cytotoxicity. Interestingly, anti-neuraminidase antibodies weakly induced antibody-dependent cell-mediated cytotoxicity and enhanced induction in the presence of HA stalk-binding antibodies in an additive manner. Our data demonstrate that antibody specificity plays an important role in the regulation of ADCC, and that cross-talk among antibodies of varying specificities determines the magnitude of Fc receptor-mediated effector functions.


Cells ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 1399 ◽  
Author(s):  
Jianzhou Cui ◽  
Dhakshayini Morgan ◽  
Dao Han Cheng ◽  
Sok Lin Foo ◽  
Gracemary L. R. Yap ◽  
...  

Influenza viruses have been shown to use autophagy for their survival. However, the proteins and mechanisms involved in the autophagic process triggered by the influenza virus are unclear. Annexin-A1 (ANXA1) is an immunomodulatory protein involved in the regulation of the immune response and Influenza A virus (IAV) replication. In this study, using clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 (CRISPR associated protein 9) deletion of ANXA1, combined with the next-generation sequencing, we systematically analyzed the critical role of ANXA1 in IAV infection as well as the detailed processes governing IAV infection, such as macroautophagy. A number of differentially expressed genes were uniquely expressed in influenza A virus-infected A549 parental cells and A549 ∆ANXA1 cells, which were enriched in the immune system and infection-related pathways. Gene ontology and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway revealed the role of ANXA1 in autophagy. To validate this, the effect of mechanistic target of rapamycin (mTOR) inhibitors, starvation and influenza infection on autophagy was determined, and our results demonstrate that ANXA1 enhances autophagy induced by conventional autophagy inducers and influenza virus. These results will help us to understand the underlying mechanisms of IAV infection and provide a potential therapeutic target for restricting influenza viral replication and infection.


2015 ◽  
pp. gkv1078 ◽  
Author(s):  
Fang Li ◽  
Yuhai Chen ◽  
Zhaoyuan Zhang ◽  
Jing Ouyang ◽  
Yi Wang ◽  
...  

2008 ◽  
Vol 83 (4) ◽  
pp. 1611-1616 ◽  
Author(s):  
Rei-Lin Kuo ◽  
Robert M. Krug

ABSTRACT The NS1A protein of influenza A virus binds the cellular CPSF30 protein, thereby inhibiting the 3′-end processing of all cellular pre-mRNAs, including beta interferon pre-mRNA. X-ray crystallography identified the CPSF30-binding pocket on the influenza virus A/Udorn/72 (Ud) NS1A protein and the critical role of two hydrophobic NS1A amino acids outside the pocket, F103 and M106, in stabilizing the CPSF30-NS1A complex. Although the NS1A protein of the 1997 H5N1 influenza A/Hong Kong/483/97 (HK97) virus contains L (not F) at position 103 and I (not M) at position 106, it binds CPSF30 in vivo to a significant extent because cognate (HK97) internal proteins stabilize the CPSF30-NS1A complex in infected cells. Here we show that the cognate HK97 polymerase complex, containing the viral polymerase proteins (PB1, PB2, and PA) and the nucleocapsid protein (NP), is responsible for this stabilization. The noncognate Ud polymerase complex cannot carry out this stabilization, but it can stabilize CPSF30 binding to a mutated (F103L M106I) cognate Ud NS1A protein. These results suggested that the viral polymerase complex is an integral component of the CPSF30-NS1A protein complex in infected cells even when the cognate NS1A protein contains F103 and M106, and we show that this is indeed the case. Finally, we show that cognate PA protein and NP, but not cognate PB1 and PB2 proteins, are required for stabilizing the CPSF30-NS1A complex, indicating that the NS1A protein interacts primarily with its cognate PA protein and NP in a complex that includes the cellular CPSF30 protein.


2019 ◽  
Vol 77 (6) ◽  
Author(s):  
Fangzhao Chen ◽  
Teng Liu ◽  
Jiagui Xu ◽  
Yingna Huang ◽  
Shuwen Liu ◽  
...  

ABSTRACT Generally, influenza virus neuraminidase (NA) plays a critical role in the release stage of influenza virus. Recently, it has been found that NA may promote influenza virus to access the target cells. However, the mechanism remain unclear. Here, we reported that peramivir indeed possessed anti-influenza A virus (IAV) activity in the stage of viral entry. Importantly, we verified the critical residues of influenza NA involved in the viral entry. As a result, peramivir as an efficient NA inhibitor could suppress the initiation of IAV infection. Furthermore, mutational analysis showed NA might be associated with viral entry via amino acids residues R118, E119, D151, R152, W178, I222, E227, E276, R292 and R371. Our results demonstrated NA must contain the key amino acid residues can involve in IAV entry.


2011 ◽  
Vol 7 (11) ◽  
pp. e1002341 ◽  
Author(s):  
Toshihiro Ito ◽  
Ronald M. Allen ◽  
William F. Carson ◽  
Matthew Schaller ◽  
Karen A. Cavassani ◽  
...  

2017 ◽  
Vol 92 (1) ◽  
Author(s):  
Dylan A. Frabutt ◽  
Bin Wang ◽  
Sana Riaz ◽  
Richard C. Schwartz ◽  
Yong-Hui Zheng

ABSTRACT Innate immunity provides an immediate defense against infection after host cells sense danger signals from microbes. Endoplasmic reticulum (ER) stress arises from accumulation of misfolded/unfolded proteins when protein load overwhelms the ER folding capacity, which activates the unfolded protein response (UPR) to restore ER homeostasis. Here, we show that a mechanism for antiviral innate immunity is triggered after the ER stress pathway senses viral glycoproteins. When hemagglutinin (HA) glycoproteins from influenza A virus (IAV) are expressed in cells, ER stress is induced, resulting in rapid HA degradation via proteasomes. The ER-associated protein degradation (ERAD) pathway, an important UPR function for destruction of aberrant proteins, mediates HA degradation. Three class I α-mannosidases were identified to play a critical role in the degradation process, including EDEM1, EDEM2, and ERManI. HA degradation requires either ERManI enzymatic activity or EDEM1/EDEM2 enzymatic activity when ERManI is not expressed, indicating that demannosylation is a critical step for HA degradation. Silencing of EDEM1, EDEM2, and ERManI strongly increases HA expression and promotes IAV replication. Thus, the ER stress pathway senses influenza HA as “nonself” or misfolded protein and sorts HA to ERAD for degradation, resulting in inhibition of IAV replication. IMPORTANCE Viral nucleic acids are recognized as important inducers of innate antiviral immune responses that are sensed by multiple classes of sensors, but other inducers and sensors of viral innate immunity need to be identified and characterized. Here, we used IAV to investigate how host innate immunity is activated. We found that IAV HA glycoproteins induce ER stress, resulting in HA degradation via ERAD and consequent inhibition of IAV replication. In addition, we have identified three class I α-mannosidases, EDEM1, EDEM2, and ERManI, which play a critical role in initiating HA degradation. Knockdown of these proteins substantially increases HA expression and IAV replication. The enzymatic activities and joint actions of these mannosidases are required for this antiviral activity. Our results suggest that viral glycoproteins induce a strong innate antiviral response through activating the ER stress pathway during viral infection.


Sign in / Sign up

Export Citation Format

Share Document