[Investigation on immunological factors of non- and low-responders to hepatitis B vaccine].

We investigated the immunological factors concerning the backgrounds of non- and low-responders who could not respond well to the hepatitis B (HB) vaccine. We injected 10 micrograms of the recombinant HB vaccine to the medical staffs of our hospital intramuscularly three times, 199 subjects of whom could receive the full course of immunization with the HB surface (HBs) antigen. We found that 14 subjects were non-responders whose titer of HBs antibody was under the 1.9 cut off index (C.I.) examined by radioimmunoassay (RIA) and 47 ones were low-responders whose titers were between 2.0 to 9.9 C.I. and the frequency of non- and low-responders was higher in males after the full course of HB vaccination. We chose 46 subjects and divided them into 4 groups according to the titer of HBs antibody at 8 and 28 weeks. We compared those groups to each other according to the amounts of total protein, gamma-globulin, IgG, IgA and IgM, numbers of peripheral white blood cells and lymphocytes, and percentages of peripheral lymphocyte and subsets of T cell including the examination by two-color flow cytometry using monoclonal antibodies. However we could not get any significant difference in any of those immunological factors by T assay. From these findings we suggest that the response to the HB vaccine does not depend on the quantity of the immunological factors before vaccination but on specific reactivity to HBs antigen after vaccination.