Interleukin 1 production by human monocytes in the course of HIV infection.

Interleukin 1 (IL-1) secretion was studied in cultures of peripheral blood monocytes originating from asymptomatic HIV carriers and patients with clinically apparent HIV infection, diagnosed as persistent, generalised lymphadenopathy (PGL) or AIDS-related complex (ARC). The spontaneous and LPS-stimulated release of the cytokine was studied. IL-1 was assayed using concanavalin A (Con A) thymocyte co-activation assay, applying colorimetric assay of proliferation. No disturbances in IL-1 release were detected in asymptomatic HIV carriers while monocytes of patients at the productive stage of infection (either from PGL or ARC patients) demonstrated marked spontaneous production of the cytokine. Monocytes of the patients responded to LPS stimulation in a normal fashion. Significant relationship was disclosed between spontaneous IL-1 release and a decrease in CD4 cell number in blood. The results may suggest that disturbances in monocyte function which develop following HIV infection may, at least in part, reflect a direct virus-cell interaction.