In Vitro Cytotoxicity Studies of Murine Sarcoma Virus-Induced Immunity in Mice 2 3

Abstract

The kinetics of cell-mediated and humoral immune responses to murine sarcoma virus were studied by ⁵¹chromium-release cytotoxicity assays. Adult C57BL/6N, (BALB/c X C57BL/6)F₁, and BALB/cN mice were inoculated with 4 different stocks of Moloney murine sarcoma virus, and immune reactivity wasmeasured at various times after immunization by cytotoxic reaction against the Rauscher virus-induced lymphoma, RBL-5. In general, cellular reactivity reached a maximum approximately 14 days after virus administration; humoral antibody titers did not reach their maximum levels until after 30–40 days. Considerable differences between the strains of mice and between the virus stocks were observed in tumor growth patterns and immune reactivity. There wassome correlation between experimental groups of the lack of progressive tumor growth with the degree of immune reactivity. However, immune reactivity in individual mice could not clearly be related to tumor growth pattern.