OBJECTIVETo prepare the oral solution of egg yolk hepatitis B virus (HBV)-specific transfer factor (EYHBV-TF) and evaluate its immunological activity as an immune regulator against hepatitis B.

METHODSFrom hens immunized with the Hepatitis B vaccine the egg yolk was isolated to extract the specific transfer factor EYHBV-TF, and its physicochemical properties were examined. Leukocyte adhesion inhibition test (LAI) was performed to detect the immunogenic activity of EYHBV-TF. The solution of EYHBV-TF was then administered orally in normal mice, and the specific cellular immune activity induced was assayed with delayed type skin hypersensitivity test (DTH), with the non-specific immune activity assessed with immune organ index. The immune responses induced by oral EYHBV-STF solution were compared with those by EYHBV-STF injection and by different dosages (injection and oral) of porcine spleen HBV-specific transfer factor (PSHBV-STF), porcine spleen nonspecific transfer factor, and egg yolk extracts from non-immunized hens.

RESULTSThe prepared EYHBV-STF oral solution, which met the standards for biological products, could inhibit leukocyte adhesion in vitro and significantly enhance mouse foot pad swelling, demonstrating its capability of transferring antigen-specific delayed type hypersensitivity reactions to naive recipient. EYHBV-STF oral solution also significantly improved the immune organ index in mice (P<0 01) with similar effects to those caused by EYHBV-STF injections and by PSHBV-STF injection and oral solution.

CONCLUSIONOrally administered EYHBV-STF and EYHBV-STF injection both possess hepatitis B antigen-specific cellular immune activity and can significantly enhance specific cellular immune responses.