CD27⁺ and CD27⁻ antigen-specific memory CD4⁺ T cell subsets are polyfunctional.

<p>(A) Distribution of CD27⁺ and CD27⁻ memory CD4⁺ T cells from LTBI (n = 12) and BCG (n = 9) that produce IFN-γ, TNF-α or IL-2 upon stimulation with CW antigen. The antigen-specific T cells are CD28⁺, CCR7⁻ and CD45RA⁻. Each data point corresponds to a single donor. (B) Polyfunctional cytokine responses from CD27⁺ and CD27⁻ subsets in LTBI. Data are represented as the mean percentage of responding CD4⁺ T cells that are triple producers (3+), double producers (2+) or single producers (1+) of IFN-γ, TNF-α, and IL-2 and summarized by the pie charts. Each slice of the pie represents the fractions of the total response that consists of CD4⁺ T cells positive for a given function.