CD4⁺ T-cell reconstitution after Ab-mediated CD4⁺ lymphocyte depletion in nonhuman primates. Peripheral blood (PB)– and lymph node (LN)–derived mononuclear cells were obtained from healthy SIV-uninfected sooty mangabeys (SMs) and rhesus macaques (RMs). (A) Flow cytometric staining of CD3⁺CD4⁺ T cells in PB of a representative SM (left panels) and RM (right panels) as measured before and at days 7 and 120 after Ab-mediated CD4⁺ lymphocyte depletion. (B) Fraction of CD3⁺CD4⁺ (left graph) and CD3⁺CD8⁺ (right graph) T cells, expressed as percentage variation from baseline, in the PB of SMs and RMs after CD4⁺ lymphocyte depletion. (C) Absolute number of CD3⁺CD4⁺ (left graph) and CD3⁺CD8⁺ (right graph) T cells in the PB of SMs and RMs after CD4⁺ lymphocyte depletion. (D) Fraction of CD3⁺CD4⁺ (left graph) and CD3⁺CD8⁺ (right graph) T cells, expressed as percentage variation from baseline, in the LN of SMs and RMs after CD4⁺ lymphocyte depletion. Values in panels B through D are means ± SD. SMs and RMs are shown as black squares and red triangles, respectively, and the dotted lines indicate the timing of anti-CD4 monoclonal antibody administrations.