Specific immune lysis of paramyxovirus-infected cells by H-2-compatible thymus-derived lymphocytes.

Mice exposed to paramyxovirus (Sendai) generate specifically sensitized thymus-derived lymphocytes (T cells) which, in an in vitro 51Cr release assay, interact only with virus-infected target cells sharing strong transplantation antigens. Reciprocal exclusion of cytotoxic T-cell activity is found for Sendai virus, lymphocytic choriomeningitis virus and ectromelia virus. Immune T cells are detected as early as 3 days after intraperitoneal inoculation with a large dose of Sendai virus, and cytotoxicity is generally maximal on days 5-7. Lysis is restricted to interactions where sensitized lymphocytes and virus-infected target cells (fibroblasts, tumour cells or macrophages) are compatible at the K or the D locus of one H-2 haplotype. Identity of immune response (Ir) genes is neither sufficient nor necessary. Levels of T-cell responsiveness show some variation with H-2 type. Cytotoxic T-cell activity associated with H-2b is less than that recognized for H-2k or H-2d. These differences are, however, not obviously related to Ir gene control.