Fig. 1: S1PR1 expression correlates with improved IBD outcomes.

a S1PR1 expression in the IBD gene array expression dataset (GSE66407) from colon biopsies of UC (n = 101) and CD (n = 57) patients, compared to healthy control (HC, n = 55). The definition of the box plots can be found in the ‘Methods’ section. b Correlation between S1PR1 expression and endothelial markers (left) with statistical analysis (right) in GSE66407. c S1pr1 expression in the E-MTAB-9850 dataset from DSS-induced colitis mice during inflammatory (Inf_mid (n = 2), Inf_hi (n = 3)) and recovery stages (n = 3), compared to HC (n = 3). d Correlation between S1pr1 expression and endothelial markers (left) with statistical analysis (right) in dataset E-MTAB-9850. e S1PR1 expression from scRNA-seq analysis of UC (n = 2) and HC (n = 2) patients colon biopsies, showing cell type-specific clusters (GSE114374). f S1pr1 expression from scRNA-seq analysis of colitis mice colon biopsies cell (n = 10), type-specific cluster from dataset GSE148794. g immunofluorescence (IF) showing S1PR1 (violet) in ECs of IBD patients, co-staining CD31 (red) and CD3 (green) (n = 3). Scale bar, 20 μm. h IF showing S1pr1 (violet), in IEC of colitis mice (arrows) with co-staining CD31(red) and CD3 (green) (n = 5). Scale bar, 20  m. i Schematic of DSS-induced colitis mouse model treated with SAR247799 (1 mg/kg) or FTY720 (0.3 mg/kg) via intragastric gavage. j, Reesentative colon (left), and colon length quantification (right) (n = 6). k Body weight percentage, and (l), disease activity index (DAI) (n = 6). m Colonoscopy images (top), colon length (left bottom), Evans blue dye leakage from blood vessels (bottom right) after DSS treatment. n Blood routine test showing neutrophil, lymphocyte, monocyte, and eosinophil (right) and percentages (left) (n = 6). o Percentage and counts of CD3⁺ in CD45⁺, CD4⁺ and CD8⁺ cells in CD3⁺ populations in PBMCs and LPMCs (n = 6). Data are presented as mean ± SEM; Statistical analysis: two-sided Student’s t test (a, c, j, m–o); Spearman’s rank correlation analysis (b, d). Two-way ANOVA with multiple comparisons (k, l). For (k, l), the significance of Ctrl+Vehicle vs. DSS + Vehicle is shown as red, DSS + Vehicle vs. DSS + FTY720 or DSS + SAR is shown as cyan and blue p-value respectively. All experiments were repeated three times with consistent results.