Impaired phagocyte oxidative capacity in human immunodeficiency virus-infected children

Children infected with the human immunodeficiency virus (HIV) have T helper cell deficiency, but frequent bacterial infections suggest phagocyte dysfu nction. Whole blood chemiluminescence (CL) assays were used to measure the respiratory burst capacity of phagocytes from HN-infected children, perinat ally HIV-exposed but uninfected children, and normal healthy children. Phag ocytes were stimulated by zymosan opsonized with human complement with and without priming by platelet-activating factor (PAF) or FMLP. Activities of enzymes involved in the respiratory burst, oxidase and myeloperoxidase, wer e examined after opsonin receptor-independent stimulation with PMA. Unprime d CL responses to opsonized zymosan were decreased for HIV-infected childre n with severe CD4 lymphocyte suppression compared with healthy children (P = .03), and PAF-primed CL responses to opsonized zymosan were decreased in HIV-infected children with both moderate and severe CD4 lymphocyte suppress ion (P = .02 and P = .01, respectively), despite normal or increased activi ties of the respiratory burst enzymes. These impairments may contribute to secondary bacterial infections.