Effect of Histolyticus Infection and Toxin on Transplantable Mouse Tumors. ∗

Abstract

Summary

When transplantable mouse sarcomas were infected experimentally with Cl. histolyticum, and the infection controlled by systemic injections of histolyticus antitoxin, the life span of some of the animals was prolonged for as long as 20 days beyond that of the non-infected tumor bearers. But in no instance did the infection completely destroy the tumor tissue. All surviving mice, treated eventually with penicillin in order to eradicate residual infection, developed large sarcomas. Under similar conditions, no such temporary regression was observed for transplantable mouse carcinomas.

When a study was made of the effect of histolyticus toxin on transplantable mouse tumors, it was found that systemic (intramuscular) injections of toxin were without effect, whereas repeated local injections of toxin, given either directly into the tumor mass or subeutaneously around the base of the tumor, resulted in marked regression of tumor tissue. But for the toxin preparations used, the effective dose approximated, very closely, the lethal dose, particularly when the toxin wras injected directly into the tumor mass. In no instance was there a permanent regression of the tumor.

In tissue culture, carcinoma cells were more resistant to the action of histolyticus toxin than sarcoma cells, just as normal epithelium seemed to be more resistant that stroma cells or fibroblasts. But normal and cancerous epithelium were equally resistant to concentrations of toxin that produced severe damage to sarcoma cells.