Cd10 clone hi10a

For the CD34⁺ cells purification, bone marrow mononuclear cells were isolated by Ficoll-Paque Plus (GE HealthCare) density gradient centrifugation and stained using CD34 (clone 8G12; BD Biosciences) CD64 (clone 10.1; BioLegend) CD19 (clone SJ25C1; BioLegend) CD10 (clone HI10A; BioLegend) CD3 (clone OKT3; BioLegend) CD36 (clone CLB-IVC7; Sanquin Plesmanlaan) CD61 (clone RUU-PL7F12; BD Biosciences) for 15 min at RT. CD34⁺ CD64^- CD19^- CD10^- CD3^- CD36⁺ CD61⁺ cells were then sorted in a BD FACSAria II (BD Biosciences). Purified CD34⁺ cells were directly used for scRNA-seq analysis.

To determine the phenotype of B‐cells post‐stimulation, cells were stained with LIVE/DEAD™ Fixable Aqua Dead Cell Stain Kit (Thermo Fisher, Waltham, MA, USA) and then with anti‐human IgM BV605 (clone MHM88; Biolegend), IgG BV786 (clone G18‐145; BD), CD27 APC (clone 323; Biolegend), CD20 APC‐H7 (clone 2H7; BD), CD38 PE (clone HIT2; BD), CD19 PE‐CF594 (clone HIB19; BD), CD71 PE‐Cy7 (clone CY1G4; Biolegend), IgD BUV395 (clone IA6‐2; BD) and CD21 BUV737 (clone B‐Iy4; BD). The dump channel mix consisted of BV510‐labelled anti‐human CD3 (clone OKT3), CD10 (clone HI10a), CD14 (clone M5E2) and CD16 (clone 3G8), all from Biolegend. Samples were stained according to standard techniques and fixed briefly with 1% formaldehyde before acquiring data on an LSRFortessa flow cytometer (BD Biosciences). Data were analysed using FlowJo v10.5.3 (Tree Star, Inc., Ashland, OR, USA).