Cell-mediated immunity to HBcAg in chronic HBV infection.

The role of hepatitis B core antigen (HBcAg) as a possible target of cell-mediated immune response in chronic hepatitis B virus (HBV) infection has been recently emphasized. Peripheral blood leukocytes (PBLs) from 35 chronic carriers of hepatitis B surface antigen (HBsAg) were studied in vitro for their immune response to a purified preparation of HBcAg isolated from circulating Dane particles. PBLs from all the studied HBsAg-positive patients yielded a stimulation index above 3, with values ranging from 3.1 to 38.1. None of the healthy seronegative subjects, taken as control group, had a stimulation index above 2, with a mean value +/- SD of 1.28 +/- 0.35. Levels of PBL stimulation correlated with the histologic activity of liver disease, and the differences reached statistical significance. These results indicate that lymphocyte response to HBcAg may be relevant in determining liver cell damage.