Activation of natural killer (NK) cells in vivo with H-2 and non-H-2 alloantigens.

Intraperitoneal inoculation of allogeneic lymphoid cells rapidly activates cytotoxic cells in the peritoneum which are nonadherent and express the NK-1, asialo-GM1, and Thy-1 antigens. Allogeneic spleen cells were very efficient at activating these natural killer (NK) cells, while allogeneic thymocytes were much less effective. Heat-killed allogeneic cells or sonicates also could augment NK activity.--Incompatbility at H-2K, H-2T-A, or H-2D readily evoked NK cell activity, while H-2S- and H-2I-E/C-associated a disparities did not. Non-H-2 differences also stimulated NK activity and augmentation was particularly evident in the Mls-disparate combinations. Thus, the same alloantigens which efficiently activate T cells also activate NK cells.