Fig. 1.
(a) Box plots showing proportions of programmed death receptor-1 (PD-1) on all CD8+ and CD4+ T cells and on antigen-specific CD8+CD107a+ and CD4+CD154+ subsets as indicated. Median with interquartile ranges indicated. Median Env-specific CD4+CD154+ T cells responses was zero, i.e. PD-1 fractions listed are from Env-responders only. Differences in PD-1 between antigen-specific subsets (Wilcoxon) indicated, *P < 0·01, **P = 0·01 and ***not significant (n.s.). (b) Fluorescence activated cell sorter analyses scatter plots gated on live gate lymphocytes/CD3+/CD8+ showing PD-1 fractions and HIV-specific responses of CD8+ T cells defined by CD107a expression after stimulation with Env and Gag peptide panels as indicated. Background thresholds for both markers indicated based on relevant controls. Left scatters illustrate Env- and Gag-responses of a slow progressor with a CD4 change rate at −12 × 106 CD4+ T cells/l/year and E/G ratio of 12·0. Right scatters depict a rapid progressor with CD4 change rate at −186 × 106 CD4+ T cells/l/year and an E/G ratio at 81·3.