Increased concentrations of soluble tumor necrosis factor receptor 75 but not of soluble intercellular adhesion molecule-1 are associated with the decline of CD4+ lymphocytes in HIV infection.

Immune activation seems to be involved in the pathogenesis of human immunodeficiency virus (HIV) infection. The immune activation markers neopterin and beta 2-microglobulin can predict the future rate of the decrease in CD4+ T cells. In a longitudinal study, we assessed whether the decline in the CD4+ T-cell count is associated with increased concentrations of soluble intercellular adhesion molecule-1 (sICAM-1) and soluble tumor necrosis factor receptor 75 (sTNFR 75), compared to increased concentrations of beta 2-microglobulin and urinary neopterin. Forty-seven individuals representing all stages of HIV infection were followed-up for a mean of 12.7 months (range, 8 to 16 months). The percentage of the change of the CD4+ T-cell count from study entry to study end ranged from -97 to +98%; the median was -33%. Concentrations of urinary neopterin, sTNFR 75, and beta 2-microglobulin correlated with the percentage of the change of the CD4+ T-cell count from study entry to study end (r = -0.45, confidence interval (CI) -0.65 to -0.19; r = -0.42, 95% CI -0.63 to -0.15; and r = -0.416, 95% CI -0.62 to -0.15), but those of sICAM-1 did not. This difference was found despite significant correlations between sICAM-1 and sTNFR 75 and beta 2-microglobulin. Levels of sICAM-1 obtained at study entry correlated with levels of sICAM-1 obtained at study end (r = 0.46, 95% CI 0.17 to 0.68). In a multivariate linear regression analysis, urinary neopterin and sTNFR 75 were jointly significant for the percentage of the change of the CD4+ T-cell count. These results suggest that sTNFR 75 is a useful marker to estimate disease progression in HIV infection, whereas sICAM-1 does not seem to provide any information related to the decline of the CD4+ T-cell count.