Related Experiment Videos
Inhibition of influenza C viruses by human MxA protein
M Marschall1, A Zach, A Hechtfischer
1Institut für Klinische und Molekulare Virologie, Universität Erlangen-Nürnberg, Germany. mdmarsch@viro.med.uni-erlangen.de
Abstract:
Human MxA protein was analyzed for its ability to inhibit the replication of different influenza C viruses. Three laboratory derivatives of viral strain C/Ann Arbor/1/50 were investigated, namely the parental wild-type virus C/AA-wt, the persistent variant C/AA-pi and the highly cytopathogenic variant C/AA-cyt. In addition, strain C/Paris/214/91 isolated from an influenza patient was used. Multiplication of all four viruses was suppressed in MxA-expressing Vero cells, as indicated by a decrease in viral RNA synthesis, viral protein synthesis, virion production and induction of a cytopathic effect. Inhibition correlated with the level of MxA expression. Furthermore, inhibition was independent of cell clone-specific differences in expression of virus receptors, as demonstrated by receptor reconstitution experiments. Thus, human MxA protein has antiviral activity against influenza C viruses.
Insights
Human MxA protein effectively inhibits influenza C virus replication. This antiviral activity was observed across various virus strains and correlated with MxA expression levels in cells.
Area of Science:
- Virology
- Immunology
- Molecular Biology
Background:
- Influenza C viruses (ICV) are known human pathogens.
- The antiviral mechanisms against ICV are not fully understood.
- MxA protein is an interferon-induced GTPase with known antiviral properties against other viruses.
Purpose of the Study:
- To investigate the antiviral activity of human MxA protein against influenza C viruses.
- To determine if MxA protein can inhibit the replication of different ICV strains.
- To assess the correlation between MxA expression levels and viral inhibition.
Main Methods:
- Analysis of viral replication in MxA-expressing Vero cells using four different ICV strains (C/Ann Arbor/1/50 wild-type, persistent, and cytopathogenic variants, and C/Paris/214/91).
- Quantification of viral RNA synthesis, viral protein synthesis, and virion production.
- Assessment of cytopathic effects.
- Receptor reconstitution experiments to rule out receptor-dependent inhibition.
Main Results:
- Human MxA protein significantly suppressed the multiplication of all tested influenza C viruses.
- Inhibition was evidenced by reduced viral RNA and protein synthesis, decreased virion production, and diminished cytopathic effects.
- The degree of viral inhibition correlated directly with the level of MxA protein expression.
- MxA's antiviral effect was independent of cell clone-specific virus receptor expression.
Conclusions:
- Human MxA protein demonstrates significant antiviral activity against influenza C viruses.
- MxA protein is a potential host factor for controlling ICV infections.
- Further research into MxA-mediated immunity against ICV is warranted.