Fig. 4From: Enhanced IL-6/phosphorylated STAT3 signaling is related to the imbalance of circulating T follicular helper/T follicular regulatory cells in patients with rheumatoid arthritisCorrelation between phosphorylated STAT3 (pSTAT3) expression and serum IL-6 level. The expression of pSTAT3 in CD4+CXCR5+ follicular helper T (Tfh) cells was positively correlated with serum IL-6 level (r = 0.425, P = 0.005)Back to article page