LYMPHOPROLIFERATIVE RESPONSES TO A MEROZOITE SURFACE-ANTIGEN OF PLASMODIUM-FALCIPARUM - PRELIMINARY EVIDENCE FOR SEASONAL ACTIVATION OF CD8+ HLA-DQ-RESTRICTED SUPPRESSOR CELLS/
Em. Riley et al., LYMPHOPROLIFERATIVE RESPONSES TO A MEROZOITE SURFACE-ANTIGEN OF PLASMODIUM-FALCIPARUM - PRELIMINARY EVIDENCE FOR SEASONAL ACTIVATION OF CD8+ HLA-DQ-RESTRICTED SUPPRESSOR CELLS/, Clinical and experimental immunology, 94(1), 1993, pp. 64-67
We have investigated the phenotype of human lymphocytes responding to
a defined Plasmodium falciparum malaria antigen in vitro. Cells were o
btained from the peripheral blood of malaria-immune donors from an end
emic area of West Africa and were tested for proliferation in response
to cloned fragments of a merozoite surface protein (PfMSP1). Depletio
n and inhibition studies indicated that the majority of proliferating
cells were CD4+ and restricted by HLA-DR or -DQ. A proportion of respo
nding cells appeared to be CD8+, but their response was dependent.on h
elp from CD4+ cells. In two donors there was evidence that low respons
es.could be enhanced by removal of CD8+ cells and/or blocking of antig
en presentation by anti-HLA-DQ antibodies. This phenomenon was observe
d in cells collected during the wet (malaria transmission) season but
not in cells collected from the same individual during the dry season.