Fig. 5

Defining Tfh1 differentiation condition using blood CD4⁺ T cells from patients with pSjD. (a) Representative FACS plot showing CD4⁺ T cells isolated from pSjD patient, cultured for 5 days under various conditions: 1) no stimulation, 2) TCR stimulation with CD3/28 beads, 3) TCR and IL-6, 4) TCR and IL-12, and 5) TCR + TGF-β. CXCR5 expression increased after TCR and TGF-β stimulation compared to other cytokines, especially increasing CXCR3 positive Tfh1 population. Gray-colored areas represent isotype control. (b) Statistical analysis of increasing CXCR5⁺ expression after stimulation of each cytokine showed a significant increase of CXCR5 expression after TCR and TGF-β stimulation. (pSjD: n = 5, non-stimulation vs. TCR + TGF-β stimulation: p = 0.0003, by Friedman test). (c) Among increasing Tfh subsets, CXCR3⁺ Tfh1 cells were significantly increased after TCR + TGF-β stimulation. (p = 0.0008, by Friedman test). *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001.