Extended Data Fig. 2.

(a) Principle of the FXR luciferase reporter assay used in Fig. 3a and b and Extended Data Fig. 2b. (b) Stably transfected HepG2 cells expressing luciferase under the control of an FXR-responsive element were treated with the indicated doses of CDCA. Luciferase units (luminescence) were normalized to cell viability assessed by Hoechst 33342 staining (fluorescence). Data representative of two independent experiments and presented as technical triplicates with medians connected. Weight loss (c) and clinical GVHD score (d) of survival experiment shown in Fig. 3. Mice transplanted transplanted with 10 × 10⁶ B6 BM cells alone or together with 1 × 10⁶ T cells from either Nr1h4^fl/fl (BM+T^WT) or Cd4^Cre Nr1h4^fl/fl (BM+T^ΔFXR) mice on a C57Bl/6N background. Data combined from three independent experiments (BM group n=20, BM+T groups n=30 per group) and connected as means ± S.D. (e) Survival of cohoused WT or nr1h4^−/−l (Δ FXR) B6 mice receiving BALBc BM+T. Data combined from three independent experiments (n=13 per group). Statistical significance was determined using log-rank test. (f-h) BALBc recipient mice transplanted with 10 × 10⁶ B6 BM cells alone or together with 1 × 10⁶ T cells from either Nr1h4^fl/fl (BM+T^WT) or Cd4^Cre Nr1h4^fl/fl (BM+T^ΔFXR) mice on a C57Bl/6N background. (f) Organ-specific and compound histopathological scores at day 28 post-transplant of transplanted mice with representative histology images (g). Data from one experiment (n=10 per group) and statistical significance was determined by by two-tailed Mann-Whitney test. (h) Production of IFNγ by CD4⁺ and CD8⁺ T cells in the smallI and large intestine lamina propria 14 days after transplant. Data combined from two (n=10 per group) and presented as mean ± S.D. Statistical significance was determined by by two-tailed Mann-Whitney test.