THE ROLE OF HEPATITIS-C VIRUS-SPECIFIC CD4-LYMPHOCYTES IN ACUTE AND CHRONIC HEPATITIS-C( T)

Since the discovery of hepatitis C virus it has become clear that chro nic hepatitis C is a major health problem throughout the world. Becaus e antiviral agents are of limited Value in the treatment of chronic he patitis C, research has focused on the antiviral immune response for t he development of both a protective vaccine and effective immunotherap ies for established chronic infection. Antiviral antibodies are presen t in almost all patients with chronic hepatitis C but do not seem to b e virus neutralizing, probably due to the high mutational rate of vira l envelope proteins. Studies on the antiviral T cell response have rev ealed the presence of virus-specific CD4(+) helper and CD8(+) cytotoxi c T cells in a substantial proportion of patients with chronic hepatit is C. Recent studies describe an association between strong CD4(+) T h elper cell activity to certain hepatitis C virus antigens and a self-l imited course of acute hepatitis C and possibly also a sustained respo nse to treatment with interferon-alpha. Therapeutic manipulation of th e virus-specific T cell response may thus develop into a new approach for prevention and treatment of hepatitis C virus infection.