Cell-mediated immunity assayed by 51Cr release test in mice infected with mouse adenovirus

Abstract

Immune spleen cells (ISC) from mice immunized with a sublethal dose of mouse adenovirus (M-Ad) were shown by the 51Cr release test to be cytotoxic to target mouse embryonic cells or lymphoid cells infected with M-Ad. The number of ISC required for release of statistically significant amounts of 51Cr from target cells varied from 1 sample to another, ranging from 5 to .gtoreq. 30 ISC/target cells. When 24 h infected mouse embryonic cells were used as targets, the release of 51Cr became evident in 6 h after the addition of ISC to the cells, gradually increased with time and then leveled off. Cytolytic activity of M-Ad ISC is specific for M-Ad, since ISC do not lyse mouse embryonic cells infected with human adenovirus type 12 and vice versa. Kinetic study of the development of cell-mediated immunity to M-Ad assayed by 51Cr release showed that cytolytic activity of ISC in infected mice became detectable 4 days postinfection, reached it peak level about 7-10 days postinfection and fell to undetectable levels about 10 days thereafter.