Fig. 8.

Elevated expression of IL-6R on TIGIT⁻ mTregs marks a subset of FOXP3⁺ RORγt⁺ TIGIT⁻ mTregs. (A) Expression of the canonical Th17 transcription factor RORγt was assessed on four healthy donors using intracellular flow cytometry. Data shown depicts the distribution of RORγt⁺ cells in CD45RA⁻ IL-6R^−/intTIGIT⁻; IL-6R^hiTIGIT⁻ and TIGIT⁺ CD127^lowCD25⁺ T cells; and in memory T effector cells (see gating strategy on Fig. 6). The histogram shown depicts an illustrative example of the expression of RORγt (stratified by CD45RA) on total CD4⁺ CD127^lowCD25⁺ T cells. Gating of RORγt⁺ cells as detected by mAb clone AFKJS-9 followed that of Ayyoub M et al. [4]. (B) Frequency of FOXP3⁺ cells was assessed within the RORγt⁻ and RORγt⁺ fractions of IL-6R^hiTIGIT⁻ mTregs, and in TIGIT⁺ mTregs. Illustrative histogram depicts the co-expression of FOXP3 and RORgt with TIGIT- CD45RA⁻ CD127^lowCD25⁺ T cells. Horizontal bars represent the median distribution of the assessed immune phenotypes in each group.