(a) P2RY8 ligand bioassay using the indicated concentrations of Ggg, glutathione (GSH), GG-PP, or LTC4 with 50 ng/mL CXCL12 (n=4 biological replicates). (b, c) Transwell migration assays of tonsil cells towards CXCL12 mixed with the indicated concentrations of Ggg. Left plots, representative flow cytometry of CD19+ cells showing the gate for CD38+ IgD- GC B cells (b) or of CD4+ cells showing the gate for PD-1+, CXCR5+ Tfh cells (c). Right graphs show summary data for indicated cell types. (n=3 tonsils, 2 technical replicates each). (d) Internalization assay using cells expressing OX56 epitope-tagged P2RY8, read by measuring surface OX56 levels (representative flow cytometry histogram, left). Right graphs show summarized data for the indicated receptors (n=6 biological replicates, one-way ANOVA with Bonferroni’s multiple comparisons test). Data are pooled from 3 experiments (a,b,c,d). Graphs depict mean with s.d.