Mouse Hepatitis Virus 3 Binding to Macrophages Correlates with Resistance to Experimental Infection

Mouse hepatitis virus 3 (MHV3) infection of A/J and BALB/ c mice has been used as a model of resistance/susceptibility. A/J mice recover from a mild disease after 4–6 days of infection and the BALB/ c mice develop an acute hepatitis and die after 3–4 days of infection. In view of studying the MHV3 binding to cells or cell extracts, we performed an enzyme-linked immunosorbent assay-like virus-binding assay, preparing microplates with L929 cells, A/J or BALB/ c mouse macrophages and also with proteins extracted from these cells. Higher MHV3 bindings were observed to proteins of BALB/ c macrophages than to the A/J ones. The interferon-γ (IFN-γ) activation led to a reduction of MHV3 binding only to proteins of resistant A/J mouse macrophages. Our experiments contribute to the hypothesis that IFN-γ activation of macrophages plays an important role against MHV3 infection by downregulating the expression of viral receptors.