Supplementary Figure 1: Sorting gates for T_FH cells, T_FR cells and B cells.

(a) Schematic of Suppression assay. FoxP3-GFP reporter mice were immunized with NP-OVA and 7 days later dLN were harvested and CD19⁺ B cells and CD4⁺CXCR5⁺ICOS⁺FoxP3^-CD19^- T_FH cells were cultured with or without CD4⁺CXCR5⁺ICOS⁺FoxP3⁺CD19^- T_FR cells in the presence of anti-CD3/IgM. (b) Sort strategy for sorting T_FH and T_FR cells. (c) Class switch to IgG1 in suppression assays in which B and T_FH cells were cultured with or without T_FR cells along with NP-OVA.