The Prognostic Significance in HIV Infection of Immune Activation Represented by Cell Surface Antigen and Plasma Activation Marker Changes

One hundred and eighteen HIV-infected homosexual men without AIDS and 40 control seronegative homosexual men were assessed for 23 parameters reflecting immune activation to determine prognostic significance for occurrence of AIDS. Samples cryopreserved in 1987–1989 were analyzed, with AIDS occurrence determined by mid-1992. Cell surface antigens assessed on the major lymphocyte subsets were HLA-DR, CD38, CD71, and CD25. Soluble serum molecules assessed were tumor necrosis factor alpha, soluble TNFα receptor II, soluble IL-2 receptor alpha, neopterin, and β2-microglobulin. Using a proportional hazards model, prognostic markers included decreased CD4 number and percentage; increased sIL-2R, neopterin, and β2M; increased percentage HLA-DR+ total lymphocytes and CD4+ cells; increased CD38+ total lymphocytes and CD8+ cells; increased CD71+ total lymphocytes and CD4+ cells; and decreased CD25+ total lymphocytes and CD19+ cells. After adjustment for CD4 cell levels, sIL-2R, neopterin, β2M, and CD25+ CD19 cells remained significant, indicating that additional information about AIDS risk was provided by these markers.