Percentages of circulating and proliferating Treg in TD and No TD volunteers.
A) Percentage of CD4+ T cells positive for FoxP3 expression and B) percentage of CD4+ FoxP3+ T cells positive for CTLA-4 and CD25 in PBMC obtained pre-challenge and at multiple time-points after challenge (TD n = 6; No TD n = 6). C) Percentage of CD4+ FoxP3+ CTLA-4+ CD25+ T cells expressing Ki67 (a marker of proliferation) ex vivo (TD n = 2, No TD n = 3). Values are shown as the mean +/- SEM. Scatter plots showing D) the percentage of CD4+ T cells positive for FoxP3 expression and E) the percentage of CD4+ FoxP3+ T cells positive for CTLA-4 and CD25 in PBMC obtained pre-challenge and at multiple time-points after challenge (TD n = 6; No TD n = 6). F) the percentage of CD4+ FoxP3+ CTLA-4+ CD25+ T cells expressing Ki67 (a marker of proliferation) ex vivo (TD n = 2, No TD n = 3). Means are indicated with a black horizontal line. P-values were determined using a mixed effects regression model. TD (blue squares); No TD (red circles). Values from multiple time-points were grouped together in time segments (1–4, 5–9, 10–14, and 21–28 days post-challenge) to account for variability in the samples available from each volunteer. Some volunteers had samples from multiple time-points in a time-segment resulting in more data points than the corresponding number of volunteers.
