Pneumococcal-specific CD4+ T-cell responses in peripheral blood during ART.

<p>Patients were analysed prior to initiation of ART and followed-up at 3, 6 and 12 mths ART for CD4⁺ T-cell responses. Responses from HIV-infected persons at 12 months ART were compared with HIV-negative persons recruited from the same community (<b>A</b>) <i>ex vivo</i> IFN-γ ELISpot responses to wild-type <i>Streptococcus pneumoniae</i> strain concentrated culture supernatant (CCS) (D39WT CCS) (0mth, n = 36; 3mths, n = 36; 6mths, n = 26; 12mths, n = 10; HIV-, 21) (<b>B</b>) <i>ex vivo</i> IFN-γ ELISpot responses to an isogenic pneumolysin (ply)-deficient mutant (D39Ply- CCS) (0mth, n = 36; 3mths, n = 36; 6mths, n = 26; 12mths, n = 10; HIV-, 21) (<b>C</b>) proliferative responses (8 day CFSE dilution assay) to D39WT CCS (0mth, n = 16; 6mths, n = 13; 12mths, n = 13; HIV-, 28) (<b>D</b>) proliferative responses to D39Ply- CCS (0mth, n = 17; 6mths, n = 14; 12mths, n = 13; HIV-, 28) (<b>E</b>) CD154 expression on activated CD4⁺ T cells in response to D39WT CCS (0mth, n = 33; 3mths, n = 30; 6mths, n = 30; 12mths, n = 16; HIV-, 29) (<b>F</b>) CD154 expression on activated CD4⁺ T cells in response to D39Ply- CCS (0mth, n = 30; 3mths, n = 29; 6mths, n = 28; 12mths, n = 14; HIV-, 29). Black horizontal bars represent median and IQR after background responses were substrated from all antigen-specific CD4⁺ T cell responses. Wilcoxon matched pairs were used to compare T-cell characteristics of HIV-infected persons on ART over time, and the Mann Whitney U test in the HIV-infected and HIV-uninfected comparisons. Representative flow cytometric data demonstrating CD4⁺ T-cell proliferative responses and CD154 expression and gating strategy are shown in <b><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0100640#pone.0100640.s001" target="_blank">Figure S1</a></b>.