T cell recognition in the mixed lymphocyte response. II. Ia-positive splenic adherent cells are required for non-I region-induced stimulation.
Ia-positive splenic adherent cells (SAC) have been shown to be the predominant stimulators of a mixed lymphocyte response (MLR) to whole H-2 differences, in which most of the proliferative response is directed against I region-encoded determinants. The present studies were undertaken to examine the ability of several purified lymphoid subpopulations to activate T cells in response to the non-H-2-linked MIs products or to products of the K or D regions of H-2. The results demonstrated that adherent cell-depleted populations of T and B cells were nonstimulatory, whereas SAC were potent stimulators for responses involving each of these genetic differences. Treatment of these SAC with anti-Ia and C abrogated their MLR-stimulating ability. In contrast, whereas treatment of SAC with anti-Ia and C abrogated their ability to stimulate an MLR directed against K or D region-encoded determinants, this treatment had no effect on their ability to generate a cytotoxic T lymphocyte response against these same determinants. These findings suggest that in addition to presenting allogeneic I region-encoded determinants, Ia-positive SAC also play a unique role in the presentation of non-I region-encoded alloantigens to proliferating T cells.
D000818:Animals; D002448:Cell Adhesion; D002469:Cell Separation; D006183:H-2 Antigens / Q000235:genetics; D000949:Histocompatibility Antigens Class II / Q000235:genetics; D007959:Lymphocyte Culture Test, Mixed; D051379:Mice; D008806:Mice, Inbred AKR; D008807:Mice, Inbred BALB C; D008811:Mice, Inbred DBA; D013154:Spleen / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
D006183:H-2 Antigens; D000949:Histocompatibility Antigens Class II