Additional file 1: of Enhanced IL-6/phosphorylated STAT3 signaling is related to the imbalance of circulating T follicular helper/T follicular regulatory cells in patients with rheumatoid arthritis

Figure S1. Gating strategy describing the Tfh and Tfr cells. In flow cytometry analysis, the gating strategy describing the Tfh and Tfr cells was as follows: (A) stained blood cells were gated for lymphocytes, which were further gated for CD3+ T cells. The CD3+ T cells were set to exclude the monocytes and further gated for CD4+ T cells. Then CD3+CD4+ T cells were further divided based on the expression of CXCR5, and CD4+CXCR5+ T cells were further gated for calculating the expression of PD-1, ICOS, IL-21, and pSTAT3. (B) To define Tfh and Tfr cells, CD4+ T cells were gated based on expression of CXCR5 and Foxp3. CXCR5+Foxp3− cells were defined as Tfh cells, while CXCR5+Foxp3+ cells were defined as Tfr cells. The cut off for Foxp3 in CD4+ cells was determined based on fluorescence minus one (FMO) and isotype control subjects of Foxp3. (TIF 166 kb