TGFB1 and HIV-1 infection: We did not observe any relationship between plasma TGF-β1 levels during subacute or chronic HIV-1 infection and viral load or CD4+ T cell count in the relatively small cohort of individuals studied here, but in larger studies systemic TGF-β1 has been found to be inversely correlated with CD4 count (26, 27), likewise circulating TGF-β concentrations in individuals with nonprogressive HIV-1 infection are reported to be lower than in progressors (26).