Figure 5

Bcl-X expression significantly improves B cell viability but is insufficient to drive the maturation of transitional B cells Bone marrow derived from Bcl-X transgenic (WTtg) and non-transgenic (WT) mice were infected with MIGR1 control and IkBα-viruses in vitro and transferred to lethally-irradiated recipients. Splenocytes were isolated from the MIGR1 control and IkBα-transduced chimeras two and four weeks after bone marrow transplantation. (A) Cells were stained with PE-conjugated B220 antibody and analyzed by flow cytometry. (B) Cells were co-stained with biotin-conjugated CD21 and PE-conjugated CD23 antibodies and analyzed by flow cytometry. After gating on GFP+ population, the percentage of follicular B cells (CD21+/CD23+), marginal zone B cells (CD21+/CD23-), and transitional B cells (CD21-/CD23-) were enumerated. (C) Cells were co-stained with biotin-conjugated CD24 and PE-conjugated IgM antibodies and analyzed by flow cytometry. After gating on GFP+ cells, the percentage of Transitional immature B cells (CD24-hi, IgM+) and mature B cells (CD24-lo, IgM+) were enumerated.