SELECTED PLASMODIUM-FALCIPARUM SPECIFIC IMMUNE-RESPONSES ARE MAINTAINED IN AIDS ADULTS IN BURKINA-FASO

In tropical areas where Plasmodium falciparum malaria is endemic, co-i nfection with HIV-1 does not lead to a worsening of malaria, raising q uestions about the immunological interactions between both infections. Alterations of immune response to malaria during HIV-1 infection was investigated in the town of Bobo Dioulasso, Burkina Faso. Sixty-six ad ults were enrolled, including 37 HIV-1 positive subjects with <250 CD4 (+) cells/mu l and clinical AIDS, and 29 HIV-1 negative healthy subjec ts. In vitro lymphocyte proliferation and cytokine (IFN-gamma, IL-2 an d IL-4) production were assessed in isolated mononuclear cells (PBMC) in presence of PHA, PPD or three malarial antigens: the baculovirus-ex pressed protein fi om P. falciparum Merozoite Surface Protein-1, a P. falciparum in vitro culture and a crude schizont extract. Compared wit h healthy subjects, AIDS patients presented with decreased levels of c ell proliferation and of IFN-gamma and IL-2 production, in response to all antigens except the schizont extract. Similar levels of IL-4 prod uction were obtained in both groups. Mitogenic stimulation of whole bl ood cultures was also performed, and revealed similar trends in cytoki ne production as in PBMC cultures. These results show that some compon ents of the specific human immune responses to falciparum parasites ma y not be modified during AIDS, in spite of the strong cellular alterat ions induced by HIV, namely the decrease of the CD4(+) lymphocyte subs et.