The Effects of Heterologous Anti-Thymocyte Sera in Mice

[摘要] Rabbit anti-mouse thymocyte serum was separated into its immunoglobulin fractions. Two parameters of homograft reactivity, the graft- vs. -host reaction and skin graft rejection, were used to assay the suppressive activity of IgM, IgG and IgG subunits. The IgG preparation was found to contain the most activity. A small amount of activity was present in the IgM preparation. The divalent F(ab)2 subunit was less than one-sixth as active as intact IgG while the univalent Fab piece seemingly had no in vivo effect. Maximal anti-thymocyte sera activity appeared to be dependent on intact IgG, suggesting that its mechanism of action involved a biologic function determined by the Fc part of the molecule. In addition, the crude globulin preparation contained more activity than could be accounted for on the basis of its IgG content alone, implying that different immunoglobulin fractions act in a synergistic manner.

[学科分类] 生物科学（综合）