Figure 5. c-Rel protein level dynamics during terminal B cell differentiation.

(A and B) Intracellular flow cytometry data of c-Rel protein abundance. Representative flow cytometry histograms and relative median fluorescence intensities (MFIs) of intracellular c-Rel. Individual data points of 3 or more independent experiments are plotted. Bars and numbers below graphs are geometric means. The c-Rel protein fraction that is additionally present in c-Rel transgenic mice in comparison with respective control populations is highlighted in blue. (A) c-Rel levels in GCB cells (B220⁺/CD19⁺ CD95^hiCD38^lo) normalized to non-GCB (B, B220⁺/CD19⁺ CD38⁺CD95^–) of CD19Cre^I/+ controls. (B) c-Rel expression in plasma cells (PC, B220^loCD138⁺) normalized to B cells (B, B220⁺CD138^–) of CD19Cre^I/+ controls. (C and D) Intracellular flow cytometry staining of FLAG. (C) Histograms with percentage of FLAG-positive cells of 2 representative Rel^TG CD19Cre^I/+ mice. Light blue, B cells (B220⁺CD38⁺CD95^–); dark blue, GCB cells (B220⁺CD95^hiCD38^lo); gray filled, B cells of CD19Cre^I/+ control. Gate for FLAG-positive B cell population is displayed. (D) Percentage of FLAG-positive subpopulations in B cells and GCB cells. Individual data points (n = 7) and bars representing median values are shown. SPL, spleen; LN, lymph nodes; MLN, mesenteric lymph nodes; PP, Peyer’s patches; BM, bone marrow. See Supplemental Figure 7A.