Extended Data Fig. 2: Effects of B cell subset and age on the BCR repertoire.

a, Frequencies of isotype use from BCR sequencing data from sorted naive B cells (CD19⁺IgD⁺CD27⁻); CD19⁺CD27⁻IgD^- B cells; IgD⁺ memory, B1 and marginal-zone B cells (CD19⁺CD27⁺IgD⁺); IgD⁻ memory B cells (CD19⁺CD27⁺IgD⁻CD38⁻); and plasmablasts (CD19⁺CD27⁺IgD⁻CD38⁺) from 19 healthy individuals. b, Mean CDR3 lengths (left) and mean SHM per BCR (right) from cell-sorted B cell populations from healthy individuals (n = 19). c, Plasmablast frequency per patient in peripheral blood at enrolment as a percentage of CD19⁺ B cells. d, Distribution of patient ages within this study, grouped by disease. e–g, Correlations of the BCR repertoire in PBMCs with age in healthy individuals for the mean number of somatic hypermutations per BCR per bp (e), the percentage of BCRs per isotype (f) and percentage size of the largest cluster per sample (g). For b, c, P values were calculated by two-way ANOVA; *FDR < 0.05, **FDR < 0.005, ***FDR < 0.0005 (determined by the Šidák method). For e–g, P values were calculated by two-sided Wilcoxon test; *P <0.05, **P < 0.005, ***P < 0.0005, all other values not significant. Raw P values are provided in Supplementary Table 4. For all box plots, box lines show the 25th, 50th and 75th percentiles; whiskers show the upper and lower quartiles.