Host genetics of severe influenza: from mouse Mx1 to human IRF7.

Host genetics of severe influenza: from mouse Mx1 to human IRF7. Curr Opin Immunol. 2016 Jan 4;38:109-120 Authors: Ciancanelli MJ, Abel L, Zhang SY, Casanova JL Abstract Influenza viruses cause mild to moderate respiratory illness in most people, and only rarely devastating or fatal infections. The virulence factors encoded by viral genes can explain seasonal or geographic differences at the population level but are unlikely to account for inter-individual clinical variability. Inherited or acquired immunodeficiencies may thus underlie severe cases of influenza. The crucial role of host genes was first demonstrated by forward genetics in inbred mice, with the identification of interferon (IFN)-α/β-inducible Mx1 as a canonical influenza susceptibility gene. Reverse genetics has subsequently characterized the in vivo role of other mouse genes involved in IFN-α/β and -λ immunity. A series of in vitro studies with mouse and human cells have also refined the cell-intrinsic mechanisms of protection against influenza viruses. Population-based human genetic studies have not yet uncovered variants with a significant impact. Interestingly, human primary immunodeficiencies affecting T and B cells were also not found to predispose to severe influenza. Recently however, human IRF7 was shown to be essential for IFN-α/β- and IFN-λ-dependent protective immunity against primary influenza in vivo, as inferred from a patient with life-threateni...
Source: Current Opinion in Immunology - Category: Allergy & Immunology Authors: Tags: Curr Opin Immunol Source Type: research