Expression of the costimulatory CD28 antigen on the peripheral blood lymphocytes T CD8+ in the patients with chronic hepatitis C

Virus-specific activation of the CD8+cytotoxic T lymphocytes, which may affect the extension of histopathological damage in chronic hepatitis C, is closely related to the role of the so called "costimulatory antigens", particularly CD28, allocated on the surface of the T lymphocytes. This study evaluated the display of CD28 antigen on circulating T lymphocytes CD8+ in patients with chronic hepatitis C. The eventual correlation between CD28 expression, viral load, aminotransferase levels and degree of histological damage was also studied. According to our data, the prevalence of circulating TCD8+ CD28+ cells didn't differ among anti-HCV positive, HBV positive subjects and healthy controls. In HCV-positive subjects, prevalence of TCD8+ CD28+ cells was higher in patients with chronic persistent hepatitis than in chronic active cases with a significant negative correlation with the Knodell histological "score". Further studies are required to ascertain the role of CD28+ expression in those subjects with severe hepatic histological damage due to chronic hepatitis C.