Human leukocyte antigen class I-independent pathways may contribute to hepatitis B virus-induced liver disease after liver transplantation.

The proliferative response of peripheral blood lymphocytes to the HBcAg was compared with serological, molecular and immunohistochemical parameters of hepatitis B virus infection and with biochemical and histological parameters of liver disease in a patient who received a completely human leukocyte antigen class I-mismatched liver allograft for fulminant hepatitis. The proliferative response increased progressively after transplantation, as hepatitis B virus infection became reestablished in the hepatic allograft. Strikingly, the HBcAg-specific T cells suddenly disappeared from the peripheral blood immediately before the acute onset of a severe necroinflammatory liver disease in which more than 80% of the hepatocytes expressed HBcAg. These observations are compatible with the hypothesis that human leukocyte antigen class I-independent hepatitis B virus-specific T cells might play a previously unsuspected role in the pathogenesis of hepatitis B virus-induced liver disease.