Fig. 1

Detection of circulating Tfh cells by flow cytometry. PBMCs were isolated from IgAV patients (n = 27) and age- and gender-matched healthy controls (HC; n = 15), stained with fluorophore-conjugated antibody targeting indicated proteins, and analyzed by flow cytometry. a The gating strategy to identify CD4⁺CXCR5⁺, CD4⁺CXCR5⁺ICOS⁺, CD4⁺CXCR5⁺ICOS⁺PD-1⁺, CD4⁺CXCR5⁺ICOS^highPD-1^high, and CD4⁺CXCR5⁺ICOS⁻PD-1⁺ Tfh cells. b The gating strategy to identify CXCR5 + CD45RA-IL-21+ Tfh cells