T-CELL SUBSETS IN THE HYPORESPONSIVENESS TO HEPATITIS-B SURFACE-ANTIGEN (HBSAG) AND ANTIGEN-SPECIFIC SUPPRESSOR LYMPHOCYTES IN CHRONIC HEPATITIS-B VIRUS (HBV) INFECTION

In contrast to convalescent hepatitis B patients, who exhibit the ability to elicit a specific immune response to HBsAg [hepatitis B surface antigen], patients with chronic hepatitis B virus (HBV) infection are markedly hyporesponsive to HBsAg and show a decrease in the normal ratio of OKT4-positive (helper/inducer) to OKT8-positive (suppressor/cytotoxic) lymphocytes. The role of OKT4-positive and OKT8-positive cells on cellular immune response to HBsAg was evaluated in patients with chronic HBV infection and the ability of such patients to develop antigen-specific suppressor lymphocytes after in vitro sensitization to HBsAg. Elimination of OKT8-positive cells markedly improved the in vitro lymphocyte proliferative response to HBsAg without altering the reactivity of cells from the same donor to PPD [purified protein derivative] or Candida. The degree of responsiveness to HBsAg was not affected by the depletion of OKT4-positive cells. In vitro co-culture experiments, performed in the 7 chronically HBV-infected patients who showed a proliferative response when their PBM were cultured with purified HBsAg or PPD, have demonstrated that lymphocytes from chronic HBV carriers, stimulated with HBsAg, inhibit the response of autologous peripheral mononuclear cells to HBsAg but not to the unrelated antigen PPD.