CCR6 and rheumatoid arthritis: In addition, and concordant with previous work,21,22,44,45 we found that within CD103− T cells in PsA SF, CD8+ MAIT cells and conventional Tc17-like (CD8+CD161+CCR6+) cells were significantly enriched, as well as CD4+ Treg and Th17-like (CD4+CD161+CCR6+) cells, while cytotoxic CD8+ and cytotoxic/proliferative CD4+ T cells were significantly enhanced in RA.