Relationship between interleukin-5 production and variations in eosinophil counts during HIV infection in West Africa: influence of Mycobacterium tuberculosis infection.

ABSTRACT

PIP: Eosinophils are important effectors of nonspecific immune response, with eosinophilia being a classic sign of helminthic infection, allergies, and some inflammatory processes. The authors explored whether perturbations in the production of interleukin-5 (IL-5) could account for the variations in eosinophil counts seen in HIV infection. The 491 study subjects were recruited between 1993 and 1995 in Bobo-Dioulasso, Burkina Faso. Eosinophil counts were significantly higher in CDC-B AIDS patients than in controls, but were dramatically lower among CDC-C stage subjects. Phorbol 12-myristate 13-acetate (PMA)+ionomycin-induced IL-5 production by peripheral blood mononuclear cells (PBMC) was decreased from the A stage of the disease, and significant correlations were observed between IL-5 production and eosinophil counts in tuberculosis (TB)-negative HIV-1-positive, TB-positive HIV-1-positive, and TB-positive HIV-negative patient groups. The production of IL-5 was not decreased among HIV-positive patients with TB, in contrast to HIV-positive patients without TB presenting with the same ranges of CD4+ counts. These data suggest that during HIV infection, impairment in IL-5 production is one factor associated with the paradoxal eosinopenia observed in tropical areas, but that IL-5 production during active TB is compensated by as yet unidentified cellular subsets.