Studies on Cell Mediated Immunity in Hepatitis B Vaccinees

The combination of high doses of hepatitis B immunoglobulin (HBIG) and hepatitis B vaccine (HB vaccine) were injected for the prevention of maternal infant transmission of hepatitis in 185 infants whose mothers were hepatitis B carriers. Except for 9 patients who had intrauterine infection before birth, 176 infants recieved the first injection of HBIG within 48 hours after birth. These infants were protected from any perinatal transmission, and later underwent HB vaccination. As a results, the 176 cases were classified into a group of good responders, poor responders and non responders. The good responders were the infants who acquired the anti-HBs antibody easily by vaccination, and the poor or non responders were the infants who had difficulty in producting the anti-HBs antibody inspite of frequent vaccinations. This study was to compare the group of poor or non responders with the group of good responders in terms of some of the cellular immunity. Results: 1) Poor or non responders could be infected with HBV due to the lack of active immunization. In order to prevent the HBV infection in poor or non responders, continuation of HBIG injection was required every two to three months. 2) In vitro lymphoproliferative responses to PHA-P, Con-A, PWM, PPD or Cytomegalovirus antigen in peripheral lymphocytes were normal in all three groups. The response to HBsAg was significantly decreased in the poor or non responder groups. 3) The effector cells for HBsAg consisted mainly of T lymphocytes. These were classified as the T4 subset (helper/inducer T) which expressed TAC antigen (IL-2 receptor) by the stimulation with HBsAg. 4) From these results, the deficient production of the anti-HBs antibody and the low response to in vitro lymphoproliferative activity to HBsAg in poor or non responders were specific immunological dysfunctions for HBsAg