Inhibition of spontaneous AKR leukemia by multiple inoculations of Corynebacterium parvum.

In previous studies we have shown that AKR mice could be protected from spontaneous leukemia by specific immunotherapy in combination with splenectomy. In this experiment we investigated the effects of nonspecific immunotherapy with C. parvum in a similar regimen. It was found that bi-weekly, ip inoculations of 0.7 mg of C. parvum could significantly protect AKR mice from spontaneous tumors, and that splenectomy could not modify this effect. Thus, the spleen does not appear to play a determinant role in mediating the protective effects of C. parvum, as had been suggested in other systems.