H-2b restriction of the immune response to the pl26 Plasmodium falciparum antigen

Abstract

SUMMARY Inbred BALB/c (H-2d), CBA (H-2k) and C57Bl/6 (H-2%) mice immunized with Plasmodium falciparum schizonls or culture supernatcs develop antibodies of different anligcnic specificities. It has been observed that C57B1/6 mice were unable to produce deteelable antibodies against the pl26 antigen (native molecule and p73 or p50 processed fragments) compared with other inbred miee. Similar results were obtained using BALBeongenlc mice with a lack of p126 antibody response in H-2b mice, while H-2d and H-2k mice produced antibodies against the pl26. Lymphoeyte proliferation assays performed by incubation of spleen cells with immunopurified pl26 were positive for immunized BALB/c (H-2d) and congenic H-2d or H-2k mice. On the other hand, no lymphocyte stimulation was observed with either C57B1/6 (H-2b) or congenic H-2b miee. These results suggest an MHC restriction of the immune response against the entire pi 26 (found in schizonts) and its p73 and p50 naturally processed fragments (found in culture supernates).