Evolution of tumor necrosis factor-alpha serum concentrations in HIV infected individuals treated with zidovudine

We studied the evolution of Tumor Necrosis Factor-alpha serum concentration (TNF-alpha) and CD4+ lymphocyte counts (CD4+) in a pilot cohort study of HIV-infected patients during the first year of zidovudine therapy. Data on 17 patients remaining asymptomatic during the one-year follow-up period (non progressors) were analysed. Serum samples were obtained at entry and at each follow-up visit (1, 3, 6, 9 and 12 months). TNF-alpha was quantified in pg/ml using a very sensitive radioimmunoassay (Medgenix). All patients had increased TNF-alpha at entry (median: 26.4 pg/ml). TNF-alpha decreased significantly as soon as the first month of therapy (median: 16 pg/ml). A steady state was then observed until Month 6 (median: 17.5 pg/ml), from which a slow increase appeared, without reaching the initial level (median at Month 9: 21.3, at Month 12: 19.8). During the same time, less sustained changes in CD4+ lymphocytes count and beta-2 microglobulin level were observed. The results of this pilot study suggest that, during HIV infection treated course, TNF-alpha could potentially be an additional surrogate marker to CD4+ lymphocyte count.