| Abstract: |
HCG preparations from several commercial sources were tested for their ability to inhibit mitogen-induced lymphocyte blastogenesis. Proven biologically active preparations were found to vary widely in their ability to suppress PHA response, in their toxicity to lymphocytes, and in their anti-tryptic activity. Since high concentrations of a low toxicity, low trypsin inhibitor-containing preparation did not suppress blastogenesis, we conclude that previous reports of HCG being a potent inhibitor of CMI are erroneous and the effect observed by others probably due to contaminants of the HCG preparations used in their assay systems. Our findings cast doubt on the validity of the hypothesis that HCG is a potent inhibitor of CMI and therefore of importance in the role of maternal tolerance to the fetal allograft and in escape of HCG-secreting tumors from the host immune system. © 1977 Springer-Verlag. |
