Fig. 1

Identification of B cell subsets according to Bm1-5 classification system. a and b Gating strategy for CD19⁺ B cells using an initial CD19/SSC plot and refinement of the gate using a plot of FSC vs SSC. c Bm1-5 classification from double staining for IgD and CD38 (unswitched memory Bm1: IgD⁺CD38⁻; naïve Bm2: IgD⁺CD38⁺; transitional Bm2′: IgD⁺CD38^hi; plasmablasts Bm3 + Bm4: IgD⁻CD38^hi; post-germinal memory/early eBm5: IgD⁻CD38⁺; and resting memory/late Bm5: IgD⁻CD38⁻)