The percentage of CD4+CD161+ cells in the RA SF was significantly increased (36.71, 34.99–43.18%) as compared to HC PB (P < 0.001), total RA PB (P < 0.001), and paired RA PB (25.43, 20.33–30.04%; P < 0.001) (Figures 1(b) and 2(a)), while a significantly lower percentage of CD4−CD8−CD161+ cells was observed in the RA SF (35.50, 31.49–40.45%) than in HC PB (P < 0.001), total RA PB (P < 0.001), and paired PB (65.41, 53.91–71.36%; P < 0.001) (Figures 1(d) and 2(c)). This evidence concerns the gene KLRB1 and rheumatoid arthritis.