Evolution of naive T-cell subsets under HAART. Naive T-cell (CD45RA⁺, CD27⁺) frequencies (A) and numbers (B) were quantified in CD4⁺ and CD8⁺ peripheral T cells from HIV-–infected patients. Immunologic responder (IR; n = 13) as well as poor immunologic responder (PIR; n = 7) patients are compared with untreated infected persons (P). Statistical differences between groups are shown on top (*P < .05; **P < .01). The subgroups of patients analyzed are representative of their respective patient population described in Table 1 with respect to age, CD4 counts, and viral load.