IMPAIRED ALVEOLAR MACROPHAGE ACCESSORY CELL-FUNCTION AND REDUCED INCIDENCE OF LYMPHOCYTIC ALVEOLITIS IN HIV-INFECTED PATIENTS WHO SMOKE

Objective: To determine the effects of smoking on alveolar macrophage (AM) accessory cell (AC) function and the incidence of lymphocytic alv eolitis in asymptomatic HIV-infected individuals. Methods: AM AC funct ion in smoking and nonsmoking HIV-positive volunteers was measured in concanavalin A and pokeweed mitogen assays. Mitogen-induced AM-T-cell adherence was determined. AM cytokine secretion was analyzed by interl eukin (IL)-6 bioassay and IL-1 enzyme-linked immunosorbent assay (ELIS A). The incidence of lymphocytic alveolitis in both groups was determi ned. Results: AM from smokers were significantly poorer AC than AM fro m nonsmokers. Though AM-T-cell adherence was unaffected by smoking, IL -1 and IL-6 secretion was significantly impaired. Lymphocytic alveolit is was significantly less common in HIV-infected smokers. Conclusion: Smoking reduces AM AC function in HIV-infected individuals, probably b y impairing secretion of cytokines important in T-cell proliferation. This may explain the decreased incidence of lymphocytic alveolitis in HIV-infected people who smoke.