Reduced number of immature B cells in the blood of Eμ/miR-125b-Tg mice. (A) Representative flow cytometric analysis of Hardy fractions for B cell progenitor subpopulations in the bone marrow of 8-week-old Eμ/miR-125b-Tg and control mice. Hardy fractions in bone marrow (A-F) were gated as follows: fraction A, pre/pro-B cell (B220+CD43+BP-1−CD24−); fraction BC, pro-B cells (B220+CD43+BP-1−CD24+ and B220+CD43+BP-1+CD24+); fraction D, pre-B cells (B220+CD43−IgM−IgD−); fraction E, immature B cells (B220+CD43−IgM+IgD−); and fraction F, mature B cells (B220+CD43−IgM+IgD+); the C′ fraction (B220+CD43+BP-1+CD24hi) was not resolved. (B) The frequency and number of each B-cell subpopulation in Eμ/miR-125b-Tg and control mice. (C) Representative flow cytometric analysis of immature and mature B-cell populations in peripheral blood of 8-week-old Eμ/miR-125b-Tg and control mice. Immature B cells were identified as B220+IgDlowIgMhigh, B220+CD93+, and B220+CD62Llow, and mature B cells were identified as B220+IgDhighIgMlow, B220+CD93−, and B220+CD62Lhigh. (D) The number and frequency of immature B cells (B220+CD93+) in the blood of Eμ/miR-125b-Tg and control mice. Bars represent mean values of pooled data. Data are pooled from 2 to 3 experiments and represent mean ± SEM (n = 8 mice per group). *P < .05; ***P < .001; NS, not significant.