Defects in repopulation of Rictor-deficient B cells in a competitive fitness model. BM cells of WT or Vav-Cre Rictor^fl/fl mice (CD45.2) were mixed with constant fractions of allotypically disparate WT CD45.1 marrow cells, and transferred into lethally irradiated CD45.1 recipients. Spleen (A) and BM (B-C) were analyzed 12 weeks after transplantation by counting cells of each organ and flow cytometry (n = 6 WT vs 6 cKO). Ratio of CD45.2⁺ B cells to CD45.1⁺ competitors in each recipient was calculated using flow analyses in the viable B220⁺ gates (left). Shown are representative fluorescence-activated cell sorter (FACS) profiles in the gates as indicated in the above panels (right). (C) Ratios of CD45.2⁺ IgM^- B cells and CD45.2⁺ IgM⁺ B cells to each CD45.1⁺ competitor in BM were calculated using flow cytometry as in (B).