FIGURE 1.

Anti-insulin B cells in V_H125^SD.NOD can develop spontaneous GCs and undergo IgG class switch.

Spleen, mesenteric lymph nodes, pancreatic lymph nodes, and pancreas were harvested from female V_H125^SD.NOD mice, and cells were stained for flow cytometric analysis of GC and IgG subset markers. (A) Representative flow cytometry plots identifying GC B cells (B220⁺, CD19⁺, live, GL7^high, FAS^high) among insulin-binding and non-insulin-binding B cells in pancreatic lymph nodes. The frequency of (B) insulin-binding B cells among total B cells across each organ. The frequency of Ag-binding B cells (C) or the number of insulin-binding GC B cells (D) is shown. (E) Representative flow cytometry plots identifying class-switched cells among insulin-binding and non-insulin-binding B cells (B220⁺, CD19⁺, live) from pancreatic lymph nodes. (F) The frequency of IgG1⁺ (top) and IgG2b⁺ (bottom) among insulin-binding and non-insulin-binding B cells identified as in (D) is shown. The insulin-binding GC B cell frequency (C), cell number (D), and class-switched insulin-binding B cell frequency (F) are shown for mice that had >20 insulin-binding B cells in the parent gate. Eight- to seventeen-wk-old female NOD mice were used. n ≥ 6 mice per group, n ≥ 3 experiments (A–C) and n ≥ 3 mice per group, n ≥ 2 experiments (D and E). *p < 0.05, **p < 0.01, Mann-Whitney U test.