IMMUNE-RESPONSE TO PORINS ISOLATED FROM SALMONELLA-TYPHI IN DIFFERENTMOUSE STRAINS

Outer membrane proteins (OMPs) are able to induce protection against t he challenge with S. typhi in a murine model. Both humoral and cellula r immunity are involved in the protective mechanisms. In order to dete rmine whether the responsiveness to S. typhi porins is genetically con trolled in mice, different strains were immunized i.p. with 30 mu g of OMPs isolated from S. typhi 9,12, Vi:d at days 0 and 7. On day 21, sp leen cells were recovered and the lymphoproliferative response to pori ns was assessed. The highest responses were found in mice with 11-2(k) and H-2(a) haplotypes (C3H/HeJ and A/J), intermediate responses were found in mice with H-2(b) haplotype (C57Bl/6) and the lowest repsonses in H-2(d) mice (Balb/c). These results demonstrate that the responsiv eness to S. typhi porins is in part controlled by the major histocompa tibility complex class II molecules and will help to further study the mechanisms of the immune response to these proteins.