Abstract
In his preceding paper, the author stated that chick erythrocytes agglutination of mumps virus was inhibited considerably by human mother blood serum and human umbilical cord blood serum, and that the inhibitory action of the former was much stronger than that of the latter. The titres of chick erythrocytes agglutination were lowered to the same level by the action of crude culture filtrate of V. cholerae (R. D. E. by Burnet and others), but were not so much affected by heating at 60°C for 20 minutes. The complement fixing antibody in these sera seemed not to exist. At least, no definitely positive result were obtained.
In view of the above findings, it was considered that the so-called non-specific inhibitor was abundantly contained in the mother blood sera.
Further, the residuall inhibitor after R. D. E, treatment was also discussed.
The hemagglutination inhibition titre of human and experimental animal sera were found lowered by the R. D. E. treatment, but the residual inhibitory action was simultaneously noted to certain extent in almost all sera. But, when these sera were mixed with rabbit mumps virus immune serum, the effect of the R. D. E. treatment was not recognized in most cases. Since the so-called hemagglutination inhibitory antibody was least affected by the R. D. E. treatment as was in the case of influenza virus, the author was led to believe that the residual inhibitory titre of human serum is a natural antibody. However, the author failed to believe immediately that the residual inhibitory titre of animal serum is an antibody.
Criticizing the above facts, it was not necessarily easy to learn without further study that the human residual inhibitor means. It seemed very difficult for the author to regard the human residual inhibitory titre as the genuin hemagglutination inhibitory antibody unlesss the inhibitor in the non-mumps serum was completely destroyed by the R. D. E, treatment.
The experimental data on the control tests relative to the hemagglutination inhibition by mother and umbilical cord blood sera are scheduled to be published at a latet date.
