Correlation between high-molecular-weight Fc gamma-receptor-blocking factors in serum and renal allograft survival.

In this study, we have demonstrated the occurrence of IgG class noncytotoxic, lymphocyte Fc gamma-receptor-blocking antibodies in a proportion of sera obtained from transfused uremic patients. The presence of these antibodies was not found to correlate with subsequent renal allograft survival. Serum fractionation studies did however reveal a striking correlation between graft survival and Fc gamma-receptor blocking mediated by a serum factor(s) with a sedimentation coefficient of greater than 19S. The precise nature of this factor remains to be clarified.