Fig. 6

TLR2⁺ macrophages, pDCs, and PB in the small intestine bind PSA and induce IL-10 secretion. Gating strategy for mononuclear cells isolated from a duodenum (Duod) and b ileum (Ile) of WT and Rag mice analyzed for binding of fluorescent A488-conjugated PSA (left two plots). CD45⁻ intra-epithelial cells (CD45⁻ IEC: middle histogram) and CD45⁺ gated intra-epithelial leukocytes (CD45⁺ IEL: second right histogram) isolated from the a Duod and b Ile of WT (red) and Rag (blue) mice were analyzed for reactivity to PSA-A488. CD45⁺CD11c⁻B220⁺ B cells, PDCA1⁺ B220⁺CD11c⁺ pDCs and CD138⁺B220⁺ PB and B220^low PC isolated from a Duod and b Ile of WT mice were analyzed for PSA reactivity (right histogram). Flow cytometry plots show CD11c⁺PDCA1⁻ cDC, PDCA1⁺B220⁺ pDC, and B220⁺CD19⁺ B cells isolated from spleen, MLN, PP, IEL, or LP of WT mice were stimulated with c PSA or d LTA-SA (TLR2 agonist) and analyzed for IL-10 expression. e Plots summarize data from c and d and show % IL-10⁺ B cells (left), cDCs (middle), and pDCs (right) from spleen, MLN, PP, IEL, and LP stimulated with PSA or TLR2 (LTA-SA) (n = 3 mice). All data show mean ± SEM