Role of natural killer (NK) cells in the production of the murine T lymphocyte allorecognition repertoire.

Limiting dilution cultures of alloreactive (anti-H2Kb) CTL were established from thymocyte or spleen cell pools of C3H/HeJ and their congenic bg/bg partner, or of SJL/J and their congenic bg/bg partner. CTL populations in these cultures were assayed for cross-reactive lysis of a panel of splenic Con A blasts of H2Kbm mutant mice. There was some slight elevation of frequency of CTLp in the thymocyte lymphoid pool of bg/bg mice; more strikingly, the repertoire of anti-H2Kb specificities was clearly altered in both strains in the bg/bg animals. There was apparently an increased diversity (more specificities represented at higher frequencies) in the thymocyte pool and a decreased diversity in the spleen cell CTLp pool in animals with the bg/bg marker. Similar shifts in the allorecognition repertoire of normal C3H/HeJ mice were produced by inoculation of neonatal mice with a rabbit anti-NK heteroantibody (antiasialo GM1). Preabsorption of this serum such that it lost anti-NK activity also abolished this effect of in vivo neonatal injection. Furthermore, injection of bg/bg bone marrow-reconstituted C3H/HeJ (bg/+) mice with a C3H spleen cell-derived NK line also caused a shift in the allorecognition repertoire toward that seen in the normal littermate control animals.