Genetic regulation of delayed-type hypersensitivity responses to poly (Tyr,Glu)-poly(DLAla)--poly(Lys): expression of the genetic defect in the induction and manifestation phases in H-2s and H-2f mice.

The genetic defect of H-2s and H-2s non-responder mouse strains in both the induction and manifestation phases of delayed-type hypersensitivity (DTH) responses to poly(LTyr,LGlu)-poly(DLAla)--poly(LLys)[(T,G)-A--L] was analysed. Utilizing an in vitro system to activate DTH effector T cells, we observed that non-adherent T cells of (H-2f X H-2b) F1 or (H-2s X H-2b)F1 responder mice, could not be activated on antigen bearing adherent cells of H-2f or H-2s haplotypes. On the other hand, these T cells were effectively sensitized on adherent cells derived from either F1 or parental (H-2b) responder mice. These results indicate that in these mouse strains the genetic defect, in the induction phase of DTH, is expressed at the level of the antigen presenting cell. In subsequent experiments, we were able to "correct' the non-responsiveness of H-2s recipients by transfer of educated and irradiated (H-2s X H-2b)F1 T cells together with normal F1 adherent cells. Normal non-adherent and nylon wool enriched T cells failed to restore these responses. Similarly, antigen-pulsed F1 irradiated peritoneal exudate cells could stimulate DTH responses in SJL recipients of (SJL X C57BL/6)F1 (T,G)-A--L educated cells. The genetic defect of H-2s mice in the manifestation phase of the DTH reaction is thus also expressed on the antigen presenting cell.