In addition, the percentages of Tfh-like cells were positively correlated with anti-CCP antibodies (r = 0.36, P = 0.04; Figure 2c), but not with RF-IgM (r = 0.10, P = 0.58), RF-IgG (r = 0.33, P = 0.06) and RF-IgA (r = 0.12, P = 0.51; Figure 2d) among the RA patients with high frequency of Tfh-like cells. Here, CD40LG is linked to rheumatoid arthritis.