Figure 3. GC B cells were hypersensitive to H₂O₂.

(A) Density dot plots show gating for identification of plasmablasts, GC B cells, memory B cells, and naïve B cells in human tonsils. (B) Histogram overlays show p-SFK in each B cell population (shown in A) following 2 minutes of 3.3 mM of H₂O₂ (n=3, representative data shown). Color denotes median fold change in p-SFK expression compared to unstimulated (0 mM of H₂O₂). (C) Plots illustrate the median fold change in p-PLCγ, p-SYK, and p-SRC in H₂O₂-stimulated conditions compared to the unstimulated condition (arcsinh scale). Each point represents the average of three individual tonsil specimens (n=3) stimulated for 2 minutes with the indicated concentration of H₂O₂, except for the 0.04 mM and 0.12 mM H₂O₂ stimulated conditions (where n=2). Red squares represent GC B cells and blue circles represent naïve B cells. Error bars denote the standard deviation for each point.