Fig 2: S. Typhimurium flagellin TLR5-BCR linked coengagement–mediated antibody response entails GC-like B cell and plasma cell differentiation in Tcrß-/-Tcrd-/- mice.Tcrß-/-Tcrd-/- mice were injected intraperitoneally on day 0 with nil (alum, K207) or flagellin in alum (K210) and again at day 7 with PBS or flagellin in PBS, respectively. Mice were euthanized 7 days after the second injection (day 14). The spleen, mesenteric lymph nodes (MLNs), and Peyer’s patches mononuclear cells were analyzed by fluorescence-activated cell sorting for PNA+GL7+CD95+ GC-like B cells, as identified by staining with PNA and anti-CD19, anti-GL7, anti-CD95 (Fas), anti-Bcl6 (intracellular staining), anti-IgM, anti-IgG, and anti-IgA mAbs. Plasmablasts were identified by surface staining with anti-CD19 and anti-CD138 mAbs. AID and Blimp-1 expression were analyzed in B cells of the spleens, MLNs, and Peyer’s patches in nil-injected and flagellin-injected mice and were detected by intracellular staining with anti-AID and anti–Blimp-1 mAbs followed by flow cytometry analysis. Numbers are percentages of total mononuclear cells or total B cells. Data from additional nil-injected (n = 2 mice: K208 and K209) and flagellin-injected (n = 2 mice: K211 and K212) Tcrß-/-Tcrd-/- mice are displayed in fig. S15.