Extended Data Figure 9. Identifying Igj^high B cells with FACS and droplet scRNA-seq.

a, t-SNE visualization of all Cd79a-expressing cells present in the Tabula Muris Senis FACS dataset (17 tissues). Colored clusters as identified with the Seurat software toolkit. Igj^high B cell cluster 11 highlighted. n=10,867 cells. b, t-SNE in (a) colored by the Igj^high B cell markers Igj, Xbp1 and Derl3. c, GO terms enriched among the top 300 marker genes of Igj^high (n=129 cells) versus Igj^low(n=10,738 cells)(FACS). q-values estimated with Benjamini-Hochberg for each database separately, and for GO classes (molecular function, cellular component, biological process) independently. d, Distribution of Igj^high as percentages of Cd79a expressing cells per tissue. e, Percentage of Igj^high B cells of all Cd79a expressing cells across all tissues. n=5 (3mo) & n=4 (24mo) independent animals. T-test, means ± SEM. f, t-SNE visualization of all Cd79a-expressing cells present in the Tabula Muris Senis droplet dataset (17 tissues). Colored clusters as identified with the Seurat software toolkit. IgJ^high B cell cluster 5 highlighted. n=23,796 cells. g, t-SNE in (f) colored by the B cell marker Cd79a and Igj^high B cell marker Derl3. h, Percentage of Igj^high B cells of all Cd79a expressing cells across all tissues. i, Heatmap of the z-transformed Igj expression trajectories across bone (n=54), marrow (n=51), spleen (n=54), liver (n=50), GAT (n=52), kidney (n=52), heart (n=52), muscle (n=52). j, mRNA expression change of Igj in human visceral fat (20s n=25; 50s n=124; 70s n=12) and subcutaneous fat (20s n=32; 50s n=149; 70s n=13) (data from GTEx consortium). Boxplot (median, 1st and 3rd quartiles). k, Number of Igj^high B cells with successfully assembled B cell receptor locus, split by animal and immunoglobulin class. l, Clonally amplified Igj^high B cells as detected in animal 1 and 3, grouped by tissue of origin (color) and immunoglobulin class (shape).