KLRB1 and rheumatoid arthritis: However, there were no significant differences in the percentage of CD8+CD161+ T cells among HC PB, total RA PB, RA SF (17.75, 14.06–23.27%) and paired PB (18.12, 15.96–33.80%) (all P > 0.05) (Figures 1(c) and 2(b)).