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SOLUBLE TRANSPLANTATION ANTIGENS FURTHER STUDIES OF THEIR TOLEROGENIC PROPERTIES

SUMMARY Further studies of the biological effects of solubilized partially purified H-2a antigen are reported. Twenty-eight of thirty preparations studied revealed activity in regularly inducing humoral tolerance (HT) in congenic B10.D2 mice. Cell-mediated activity was retained in HT mice, however, as revealed by skin graft rejection. HT was retained in one group of mice in the absence of continued antigen injection for 16 weeks. Daily treatment with 0.4 μg (protein) was as effective as 40 μg in the induction of humoral unresponsiveness, but a single injection of antigen at birth was ineffective in inducing a lasting HT. Preliminary evidence was obtained to indicate induction of HT in adult immunodeficient B10.D2 mice. These results are discussed in terms of present concepts of tolerance induction.