Gut-associated IL-1R1⁺ CD4⁺ Lin⁻ LTi-like cells are located predominantly in the intestinal lamina propria.

<p>(A) Representative FACS scatter plots depicting IL-1R1⁺ cells as a percentage of total CD4⁺ or CD8⁺ cells in spleen and gut-associated compartments of WT C57BL/6J mice. Numbers represent percentage of CD4⁺ or CD8⁺ cells expressing IL-1R1. (B and C) Bar graph depicting IL-1R1⁺ cells as a percentage of total CD4⁺ (B) or CD8⁺ (C) cells in spleen and gut-associated compartments of WT C57BL/6J mice. Bar represents median; error bar represents standard error. Filled bars represent anti-IL-1R1 flurophore-conjugated antibodies; empty bars represent isotype control antibodies. Spl, spleen; MLN, mesenteric lymph nodes; SI, small intestine; IEL, intraepithelial lymphocytes; LPL, lamina propria lymphocytes. Data collected from three independent experiments. (D) Gating scheme for IL-1R1⁺ CD4⁺ cells. SSC, side scatter. FSC, forward scatter. Number is the percent of CD4⁺ CD3⁻ lymphocytes that are IL-1R1⁺ in WT C57BL/6J mice. (E) Scatter plot depicting IL-1R1⁺ CD4⁺ cells in Rag1^−/− C57BL/6J mice. Number is the percent of CD4⁺ lymphocytes that are IL-1R1⁺ in Rag1^−/− mice. Gated on CD4⁺ lymphocytes as in (D). (F) FACS histograms demonstrating expression of c-kit, CD127, RORγt, and Lin in WT C57BL/6J mice. Plots are gated on IL-1R1⁺ CD4⁺ cells. Empty, isotype control; filled, antibody. *, p<0.05; **, p<0.01; NS, not significant.