The Effects of Heterologous Anti-Thymocyte Sera in Mice: II. Quantitative Evaluation of IgM, IgG, and Their Subunits in Suppressing Homograft Reactions

摘要: Summary 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 suppressive activity IgM, IgG subunits. The preparation found contain most activity. A small amount present in IgM preparation. divalent F(ab) 2 subunit less than one-sixth as active intact while univalent Fab piece seemingly had no vivo effect. Maximal anti-thymocyte sera appeared be dependent on IgG, suggesting that mechanism action involved a biologic function determined by Fc part molecule. In addition, crude globulin contained more could accounted for basis content alone, implying different fractions act synergistic manner.