Fig. 3.

A substantial number of B cells lose sIgA expression in V_HQ52^NT mice. (A) Absolute number of CD19⁺ B cells in BM, inguinal LNs and SP of controls (n = 6), and V_HQ52^NT HT (n = 7) mice. (B) Frequency of splenic CD19⁺-gated sIgA⁺ B cells in representative V_HQ52^NT-HT HT animals and littermate controls, as determined by flow cytometric analysis. Numbers indicate percentage of sIgA⁺ B cells. (C) Pie chart representation of Vκ gene rearrangement analysis obtained from splenic IgM⁺ B cells of controls (n = 2) and IgA⁺ B cells of V_HQ52^NT-HT mice (n = 6). Each colored segment represents a unique rearrangement. Segment size defines frequency of individual Vκ rearrangements. (D) Representative flow cytometric analysis of SP B cells in controls (n = 6) and V_HQ52^NT-HT mice (n = 7) stained for sIgM and sIgA, respectively. Numbers indicate frequencies of CD19⁺-gated boxed B cells. (E) Frequency of sIgM⁺ and sIgA⁺ cells among B220⁺ B cells in lymphoid organs of V_HQ52^NT-HT mice (n = 7). (F) Representative flow cytometric analysis of cell suspensions from SP and peritoneal cavity lavages of V_HQ52^NT-HT mice, gating, respectively, on sIgM⁺ and sIgA⁺ B cells. Numbers indicate frequency of boxed B-cell subsets.