CD4 and HIV-1 infection: Although in the clinical setting IL-7 would presumably be associated with ART, as it was done in phase-1 studies in patients with chronic HIV-1 infection [29], [30], we deliberately avoided the use of virus-suppressive drugs in order to allow for an unbiased evaluation of the effects of IL-7 on CD4+ T-cell depletion, which is the hallmark of HIV-1/SIV-induced pathogenesis during primary infection.