Characterization of CD4⁺/CD57⁺/CD27^– T cells. (A) CD4⁺ lymphocytes were gated on the CD57⁺/CD27^– profile for each patient sample and compared with the remaining bulk CD4⁺ population for that patient with respect to expression of various markers, including CCR7, CD45RA, CD28, DNAM1, TIGIT, CD45RO, KLRG1, CTLA4, TIM3, PD1, FASL, Granzyme B, and transcription factors EOMES, T-bet, GATA3, FOXP3, RORγT, and BCL6. Representative plots for markers are shown. (B) Respective geometric mean of fluorescent intensity (MFI) comparing CD57⁺/CD27^– CD4⁺ T cells to remaining bulk CD4⁺ T cells. (C) Production of IFN-γ, TNF, GM-CSF, IL-4, IL-10, IL-17A, and IL-22 are shown for a representative sample of the CD57⁺/CD27^– CD4⁺ T-cell population. The gating strategy used to identify positive or negative expression is illustrated. (D) Representative profile for each cytokine is shown for both CD57⁺/CD27^– CD4⁺ T cells and remaining CD4⁺ T cells with respect to percent of positive cells identified by the gating strategy shown in panel C. Median with interquartile range are illustrated. Statistical significance is denoted by *P < .05, **P < .01, ***P < .001, ****P < .0001.