The Action of Anti-Ehrlich Ascites Tumor Antibody^*

The γ-globulin fraction of rabbit anti-Ehrlich ascites tumor serum was prepared by alcoholic fractionation. Preliminary treatment of the living ascites tumor with the γ-globulin and guinea pig complement prior to transplantation prevented tumor growth. Heating the complement (56° C., 30 min.) destroyed the inhibiting effect of the combination.

Attempts were made to characterize this effect on the tumor cells. The use of several histochemical technics revealed differences between these γ-globulin-complement (G-C)-treated tumor cells and those treated with one or the other of the components. By the neotetrazolium method and direct Warburg measurements, it was found that the G-C-treated cells were unable to utilize either their endogenous substrate or exogenous glucose; they were as capable of utilizing succinate as were the γ-globulin- or complement-treated cells. This action of G-C also occured with the Krebs ascites tumor and, to a variable degree, with some normal mouse tissues.

When G-C was injected intraperitoneally into mice bearing actively growing ascites tumor, the average survival time relative to untreated controls was approximately doubled, and intermediary effects were observed with the separate components. Progressive cellular degeneration with loss of cytoplasmic, nucleolar, and finally chromatin basophilia was observed in a histologic study of the in vivo G-C treated cells.