Correlation between CD7 status and recovery of CD4 T cells on ART. CD7 expression in the CD8 T-cell compartment in PBMCs from adult subjects infected with HIV-1 on ART (n = 32) was assessed by 4-color flow cytometry, and the correlation between (A) CD7^high, (B) CD7^low, and (C) CD7^negative subset frequencies and CD4 T-cell counts was analyzed by linear regression. (D) A similar analysis was performed on PBMCs from 16 pediatric subjects infected with HIV-1 on ART. CD7 expression in CD8 T cells was analyzed in relation to both absolute CD4 T-cell counts (left) and the CD4 T-cell percentage (right). In the pediatric group the CD7^low and CD7^negative subsets were fused in the analysis because the CD7^negative subset frequency was very low.