Fig 1: S1PR2 fate-mapped GC B cells and GC Tfh cells are recalled in boost immunization as GC B cells, GC-derived CD44+ memory B cells and plasma cells, or Tfh and Th1 cells, respectively(A) S1pr2ERT2-creRosa26stop-flox-RFP mice recall experiment overview.(B) Relative frequency of S1PR2-RFP+ fate-mapped mILN B cells at day 49.(C) Relative frequency of S1PR2-RFP+ fate-mapped mILN GC B cells.(D) Relative frequency of GC phenotype within S1PR2-RFP+ fate-mapped mILN B cells.(E) Median flow cytometry plots of RBD+ S1PR2-RFP+ fate-mapped mILN B cell subsets.(F) Relative frequency of RBD+ S1PR2-RFP+ fate-mapped mILN B cell subsets at days 14 and 49, respectively.(G) Relative frequency of S1PR2-RFP+ fate-mapped plasma cells.(H) Relative frequency of S1PR2-RFP+ fate-mapped CD4+ FOXP3- cells.(I) Day 49 median flow cytometry plots of S1PR2-RFP+ fate-mapped mILN FOXP3- CD4+ cell subsets.(J) Relative frequency of S1PR2-RFP+ fate-mapped mILN FOXP3- CD4+ cell subsets.(K) Relative frequency of S1PR2-RFP+ fate-mapped mILN Th1 (TBET+ CXCR3+ CXCR5- PD1- CD44+ CD62L- FOXP3- CD4+) cells.For each time point, n = 5. For (C), (D), (H), and (K), the Mann-Whitney test was used. For (G), multiple Mann-Whitney tests per row were used, with p values corrected for multiple comparison analysis with the Holm-Šídák method. In (B)–(D), (G), (H), and (K), each symbol represents a biological replicate and the bar height the mean. In (F) and (J), bar heights represent mean, and error bars represent the standard deviation. Data are representative of two individual experiments.