H-2-associated specificity of virus-immune cytotoxic T cells from H-2 mutant and wild-type mice: M523 (H-2K^ka) and M505(H-2K^bd) do, M504 (H-2D^da) and M506(H-2K^fa) do not crossreact with wild-type H-2K or H-2D

B10.A(3R) (H-2K^b) mice infected with lymphocytic choriomeningitis virus (LCMV) or vaccinia virus generate cytotoxic T cells capable of specifically lysing virus-infected macrophage target cells from H-2K^b mutant mice M505 (H-2K^bd), and vice versa. Similarly, virus-immune B10.A(4R) (H-2K^k) T cells specifically lyse infected targets from M523 (H-2K^ka), and vice versa. In contrast, virus-specific cytotoxic T cells from neither M504 (H-2D^da) and B10.A(5R) (H-2D^d) nor M506 (H-2K^fa) and B10.M(11R) (H-2K^f) mutually crossreact at the cytotoxic effector-cell level. As far as tested, the crossreactivity patterns between wild-type and mutant K or D specificities are identical for LCMV- and vaccinia virus-immune spleen cells. Although this finding is no proof for either the altered self nor the dual recognition concept of T-cell recognition, it may be compatible with the latter model.