Figure 3.

SRBC-induced GC formation in Cγ1^Cre/wtPtpn6^fl/fl mice is largely unaffected

Germinal center response was analyzed 5 days post intravenous SRBC immunization of Cγ1^Cre/wtPtpn6^fl/wt (fl/wt) and Cγ1^Cre/wtPtpn6^fl/fl (fl/fl) mice.

(A) Representative contour plots gating GC B cells from spleen (lymphocytes/singlets/live/CD138^-B220⁺CD38⁻Fas⁺). Right panel shows percentage of B220⁺ B cells and total numbers per spleen. Data are combined from two independent experiments.

(B) pSYK expression in GC B cells. Right panel shows pSYK median fluorescence intensity (MFI) in GC B cells; results are representative of two independent experiments. Gray histogram shows the fluorescence minus one (FMO) control for pSYK staining.

(C) Apoptosis rate based on the binding of Annexin V and 7-AAD, active caspase-3 in IgG1⁺, or IgM⁺ cells as in Figure 2. % of GC B cells; data are combined from two independent experiments.

(D) Spleen sections from Shp1^fl/wt (fl/wt) and Shp1^fl/fl (fl/fl) mice staining for B cell follicles (IgD, green), T cell zone (CD4, blue), and proliferating cells (Ki67 in red); scale bar, 200 μm. Positive area of Ki67⁺IgD^- was calculated as percentage of total splenic area. Each symbol corresponds to one animal; horizontal lines indicate the mean. n.s. not significant, ∗∗p < 0.01 (two-tailed t test).