Identification and characterization of influenza virus activators in the human lung

点击翻译按钮获取中文摘要

Influenza epidemics and intermittent pandemics threaten human health. This threat is not adequately met by currently available vaccines and antivirals due to the ever changing nature of influenza viruses. Vaccines need to be reformulated constantly to match the currently circulating viruses and resistance mutations in the viral genome can render antivirals ineffective. The identification of host cell factors that are required for viral spread but dispensable for cellular survival might define novel, attractive targets for intervention and may yield important insights into influenza pathogenesis. Activation of the viral hemagglutinin (HA) by a host cell protease is essential for viral infectivity. We have shown that the expression of the HA-activating protease TMPRSS2 is essential for H1N1 influenza A virus (IAV) spread in mice. Moreover, we and others have obtained evidence that TMPRSS2-related enzymes, termed alternative activators, can support IAV spread in cell culture and mice. However, it is currently unclear whether TMPRSS2 and/or alternative activators contribute to IAV spread in humans, and it is unknown which domains in these enzymes govern HA activation. Finally, the secondary structures of the mRNAs of HA-activating proteases and their implications for protein expression and antiviral intervention have not been examined. These questions will be addressed in the proposed project. For this, we will use state-of-the-art methodology, including SHAPE for determination of the secondary structure of mRNAs encoding HA-activating proteases, precision-cut lung slices (PCLS) and a macaque model for severe influenza in humans. The proposed studies will greatly benefit from the joint background of the project partners and their complementary expertise’s: The partners in Poland are experts in SHAPE analyses and the partners in Germany have access to key technology for assessment of IAV activation in the primate respiratory epithelium, including PCLS and a primate model for IAV infection.