Abnormal monocyte function in patients with Kaposi's sarcoma.

Monocyte-mediated functions were evaluated in the peripheral blood mononuclear cells (PBMC) of 11 previously untreated patients with Kaposi's sarcoma in association with the acquired immune deficiency syndrome (KS/AIDS). All patients had lymphadenopathy, an abnormal OKT.4/OKT.8 ratio, and a good performance status; none had clinically apparent infections at the time of testing. Monocyte functional assessments included immunoregulatory activity in phytohemagglutinin-stimulated (PHA) lymphoblastogenesis assays, natural killer (NK) assays, Interleukin 2 (IL2) production assays and, quantitation of opsonized zymosan-induced chemiluminescence responses. A group of seven hemophilia patients who had been receiving concentrated blood products and who presented with evidence of an abnormal OKT.4/OKT.8 ratio were also investigated as controls. As a group, the patients with KS/AIDS had a significantly depressed response to PHA compared with normal control subjects and patients with hemophilia; this was significantly elevated by indomethacin or by the removal of glass adherent cells. PBMC from KS/AIDS patients also had an impaired ability to produce IL2 in PHA-stimulated cultures which was enhanced by the addition of indomethacin. NK function was also suppressed in both groups of patients, but could not be augmented by the removal of glass adherent monocytes. Chemiluminescence responses to opsonized zymosan were variable, but found to be significantly different from normal in the majority of patients studied. These results demonstrate that monocyte function can be abnormal in patients with KS/AIDS and might contribute to some of the immunologic impairment seen in these patients.