Elevated CD4+/CD25+ T cell frequency and function during acute hepatitis C presage chronic evolution.

Hepatitis C virus (HCV) determines an acute hepatitis evolving to persistent infection in 50–80% of patients. Different mechanisms have been proposed to explain disease evolution, including viral escape, failure of the T helper immune network, and host genetic factors. Among CD4+ T cell subsets, lymphocytes expressing constitutively CD25 (interleukin 2 receptor alpha chain), namely T regulatory cells (Treg), appear to play a critical role in controlling chronic evolution of HCV mediated liver diseases. Here we investigate the frequency and functional activity of CD3+/CD4+/CD25+ Tregs in acute HCV infection in relation to its evolution over time