Immunopathogenesis of viral hepatitis C. Immunological markers of the disease progression

: Results of studies of immune response during hepatitis C virus (HCV) infection were reviewed in order to reveal immunologic markers of the disease progression. Genetic heterogeneity of HCV and immunogenetic features of the host determine heterogeneity of immune response to the virus and differences in the course of the disease and outcomes. Spontaneous elimination of HCV-infection in acute phase occurs due to vigorous and sustained multispecific Th1-response toviral antigens. During such response proliferation of virus-specific CD4+ T-cells and secretion of IFN-gamma by them are observed, otherwise chronic hepatitis develops. Great importance in persistence of HCV as well as in quantitative and functional suppression of HCV-specific CD8+ T-cells has increased number of CD4+ CD25+ regulatory T-cells. Cellular immune response plays a key role not only in the elimination of HCV, but also in liver pathology associated with HCV-infection. Progression of the process and shift to its chronic form are also associated with decrease of production of IFN-gamma, alpha, IL-2 by peripheral blood mononuclear cells and increase of TNF-alpha, IFN-gamma, IL-4, IL-2r levels in blood serum.