Kinetics of lymphocyte transformation in mice immunized with viable avirulent forms of Cryptococcus neoformans.
A murine model was developed to study the cell-mediated immune response of mice immunized with one of two live, avirulent forms of Cryptococcus neoformans: a nonencapsulated mutant and a thinly encapsulated pseudohyphal variant. A lymphocyte transformation assay was used to evaluate the cellular response of control and sensitized spleen cells after in vitro incubation with three merthiolate-killed whole-cell antigens of C. neoformans. An antigen-to-spleen cell ratio of 10:1 and 5 days of incubation of antigen-spleen cell mixtures were established as optimal conditions for maximum lymphocyte transformation. Maximum responses occurred from 2 to 3 weeks after the last of eight weekly intraperitoneal inoculations of C. neoformans. This assay provided an accurate, reproducible method of studying cell-mediated immunity to C. neoformans, and applications to the study of cryptococcal pathogenesis are proposed.
D000818:Animals; D003454:Cryptococcus / Q000276:immunology*; D003455:Cryptococcus neoformans / Q000276:immunology* / Q000472:pathogenicity; D004306:Dose-Response Relationship, Immunologic; D007114:Immunization; D007700:Kinetics; D008213:Lymphocyte Activation; D008297:Male; D051379:Mice; D013154:Spleen / Q000276:immunology