Figure 1

Flow cytometric analysis of lymphocyte populations in AUF1^-/- mice. (a) Single cell suspensions from spleen (SP), bone marrow (BM), lymph node (LN), peritoneal cavity (PerC), and thymus (Thy) of AUF1^-/- (KO) and wild-type (WT) littermates were stained with the indicated antibodies and analyzed. Numbers indicate the percentage of lymphoid cells in quadrants or enclosed within indicated gates. Contour plots gated for B220⁺ or CD3⁺ lymphocytes are indicated. Note decrease in FO B cells in AUF1^-/- spleens as represented by IgD^hiIgM^lo, CD21^intCD24^lo, or CD21^intCD23^hi gates. There is also an increase in the proportion of MZ B cells in KO spleens as represented by CD21^hiCD23^lo gate. (b) Splenic B cells were analyzed for IgD and IgM expression (left panels) and gated populations were then analyzed for CD21 expression (right panels). This analysis distinguishes five different splenic populations (from left to right): NF, IgM^highIgD^lowCD21^low; MZ, IgM^highIgD^lowCD21^high; FO-II, IgM^highIgD^highCD21^int; MZP, IgM^highIgD^highCD21^high; and FO-I, IgM^lowIgD^highCD21^int. Three mice were analyzed in each group. (c) Decreased CD23 expression in AUF1^-/- B cells (B220⁺) and FO B cells (IgM^loIgD^hi) from AUF1^-/- mice. (d) AUF1 expression in B cell subsets as determined by FACS (left panels) or immunoblot analysis (right panels). In immunoblot analysis, the staining with AUF1 shows three bands corresponding to the four isoforms of AUF1, and level of eIF4E is shown as a control. Numbers in parenthesis in (c) and (d) depict mean fluorescence intensity (MFI).