PP4 deficiency induces a severe block in B cell development.

<p>(A) Flow cytometric profiles of: total BM lymphocytes from WT and cKO mice analyzed for B220 vs CD43 expression (left panel); B220⁺CD43⁺ BM lymphocytes analyzed for CD24 vs BP-1 (middle panel); and B220⁺CD43⁻ BM lymphocytes analyzed for IgM vs IgD (right panel). (B) Quantitative cell count analysis of Frs. A to F cells from WT and cKO mice. (C) Quantitative cell count analysis of: splenic B220⁺ B cells from WT and cKO mice. (D) Flow cytometric profiles of BM, spleen and MLN lymphocytes from WT and cKO mice (n = 4/group) analyzed for B220 vs IgM; B220⁺ splenocytes analyzed for CD21 vs CD23; and peritoneal lymphocytes analyzed for IgM vs CD5, as indicated. For A-D, results are representative of three independent experiments. For B and C, data are the mean ± SD (n = 4) (*<i>p</i>≤0.05; **<i>p</i>≤0.005).