• FluTrackers.com Inc. does not provide medical advice. Information on this web site is collected from various internet resources, and the FluTrackers board of directors makes no warranty to the safety, efficacy, correctness or completeness of the information posted on this site by any author or poster. The information collated here is for instructional and/or discussion purposes only and is NOT intended to diagnose or treat any disease, illness, or other medical condition. Every individual reader or poster should seek advice from their personal physician/healthcare practitioner before considering or using any interventions that are discussed on this website. By continuing to access this website you agree to consult your personal physican before using any interventions posted on this website, and you agree to hold harmless FluTrackers.com Inc., the board of directors, the members, and all authors and posters for any effects from use of any medication, supplement, vitamin or other substance, device, intervention, etc. mentioned in posts on this website, or other internet venues referenced in posts on this website.
  • We are not asking for any donations. Do not donate to any entity who says they are raising funds for us.

J Leukoc Biol. PB1-F2 protein of highly pathogenic influenza A (H7N9) virus selectively suppresses RNA-induced NLRP3 inflammasome activation through

tetano

Editor, Senior Moderator
J Leukoc Biol. 2020 May 9. doi: 10.1002/JLB.4AB0420-694R. [Epub ahead of print]
PB1-F2 protein of highly pathogenic influenza A (H7N9) virus selectively suppresses RNA-induced NLRP3 inflammasome activation through inhibition of MAVS-NLRP3 interaction.


Cheung PH[SUP]1[/SUP], Ye ZW[SUP]2[/SUP], Lee TT[SUP]1[/SUP], Chen H[SUP]2[/SUP], Chan CP[SUP]1[/SUP], Jin DY[SUP]1[/SUP].

Author information




Abstract

Infection with seasonal as well as highly pathogenic avian influenza A virus (IAV) causes significant morbidity and mortality worldwide. As a major virulence factor, PB1-F2 protein of IAV affects the severity of disease through multiple mechanisms including perturbation of host innate immune response. Macrophages are known to phagocytose extracellular PB1-F2 protein aggregate, leading to hyperactivation of NLRP3 inflammasome and excessive production of IL-1β and IL-18. On the other hand, when expressed intracellularly PB1-F2 suppresses NLRP3 inflammasome maturation. How extracellular and intracellular PB1-F2 orchestrates to drive viral pathogenesis remains unclear. In this study, we demonstrated the suppression of NLRP3 inflammasome activation and IL-1β secretion by PB1-F2 of highly pathogenic influenza A (H7N9) virus in infected human monocyte-derived macrophages. Mechanistically, H7N9 PB1-F2 selectively mitigated RNA-induced NLRP3 inflammasome activation by inhibiting the interaction between NLRP3 and MAVS. Intracellular PB1-F2 of H7N9 virus did not affect extracellular PB1-F2-induced NLRP3 inflammasome maturation. In contrast, PB1-F2 of WSN laboratory strain of human IAV effectively suppressed IL-1β processing and secretion induced by various stimuli including NLRP3, AIM2, and pro-IL-1β. This subtype-specific effect of PB1-F2 on inflammasome activation correlates with the induction of a proinflammatory cytokine storm by H7N9 but not WSN virus. Our findings on selective suppression of MAVS-dependent activation of NLRP3 inflammasome by H7N9 PB1-F2 have implications in viral pathogenesis and antiviral development.
?2020 Society for Leukocyte Biology.



KEYWORDS:

H7N9 virus; MAVS; NLRP3; PB1-F2 virulence factor; avian influenza A virus; inflammasome activation


PMID:32386456DOI:10.1002/JLB.4AB0420-694R
 
Back
Top Bottom