Figure 1.

Flow cytometric analysis of mouse BM, splenic, and Peyer's patch plasma cells. (A) BM cells from an adult B6.Blimp^GFP/+ were isolated and stained for analysis by flow cytometry. Cells were pre-gated based on size using FSC-A by SSC-A then doublets were excluded by gating on FSC-W by SSC-W. Live cells were analyzed by gating on Zombie Aqua negative cells. Gating on IgD^- and Dump^- cells enriched for cells that include plasma cells. Plasma cells make up the CD138^high B220^+/- population and developing B cells are found in the CD138^low B220⁺ population. Both cell populations can be further analyzed for Blimp-GFP expression to confirm plasma cell identity. (B) Cells are pre-gated as in (A) to reveal a CD138^high Sca-1⁺ population. Further analysis of these cells reveals Blimp-GFP expression and both immature B220⁺ and mature B220^- plasma cells. (C) Splenic plasma cells were analyzed by pre-gating as in (A) then examining the CD138^high Sca-1⁺ cells for Blimp-GFP expression. (D) Representative Peyer's patch cells gated as in (C). Flow cytometric graphs shown are representative of >5 independent experiments of 3 or more mice per group.