Difference in Susceptibility to Ak Leukemic Agent Between Two Substrains of Mice of G3H Line.

Abstract

Of 320 C3H mice (substrain Bittner), inoculated with filtered AK leukemic extracts, 28% developed leukemia. Of 162 C3H mice (substrain National Cancer Institute) inoculated simultaneously with the same extracts, only 4% developed leukemia. The incidence of parotid gland tumors, induced with the leukemic extracts in these 2 groups of C3H mice, was 10% versus 6%, respectively. Newborn C3H mice of the Bittner substrain are, therefore, substantially more susceptible to leukemogenic action of the cell-free AK leukemic agent, than those of the National Cancer Institute substrain, of the same line. Among the C3H mice which developed parotid tumors as a result of inoculation, at birth, with filtered Ak leukemic extracts, several developed also subcutaneous fibrosarcomas, usually near the groin, axilla, or within the abdominal wall. In one mouse, a medullary adrenal tumor also developed. Two mice, in addition to parotid gland tumors, developed carcinoma of the submaxillary gland arising in multiple small foci. In one instance, a bilateral parotid gland carcinoma developed simultaneously with leukemia.