Figure 1.

IgA⁺ plasma cells are long-lived in the BM and siLP. Under homeostatic conditions, B6.Blimp1^+/GFP mice were euthanized, then siLP and BM cells were analyzed by flow cytometry to determine the degree of surface B220 expression on plasma cells of each isotype. (A) Shown are representative images of viable, Dump^-, IgD^-, CD138⁺, Blimp-^GFP+ plasma cells that were further differentiated by surface immunoglobulin isotype and then analyzed for frequency of B220 expression. (B) Graphical representation of data in (A) compiling data from 4 mice/group. (C) Mice were treated with BrdU in their drinking water continuously until euthanasia for 0, 1, 5, and 17 days. BM and siLP cells were then stained for plasma cell isotypes as in (A), followed by intracellular staining with an anti-BrdU antibody. Each experiment used 4 mice per group and is representative of 2-4 independent experiments.