High Susceptibility of 1 to 14 Days Old C3H Mice to “Passage A” Leukemic Filtrates. ∗

Abstract

Summary

1. After 7 consecutive passages through newborn hosts, passage A leukemic filtrates could be inoculated successfully into suckling C3H mice 1 to 14 days old, inducing leukemia, but not parotid tumors, in 62% to 100% of the inoculated mice at 3.3 to 3.7 months average age. 2. The incidence of leukemia was higher in mice inoculated intraperitoneally (89%) than in those injected subcutaneously (69%). 3. Of 122 young, adult C3H mice inoculated intraperitoneally. or intracranially with leukemic filtrates. 37% developed leukemia (none parotid tumors) at 8.8 months average age. 4. Of 310 newborn C3H mice inoculated when less than 16 hours old with the same leukemic filtrates. 64% developed either leukemia (56%), or parotid tumors (8%), at 3.8 months average age. Two mice in this group developed both leukemia and parotid tumors.