NSGAb°DR1 mice reconstituted with IPEX hematopoietic stem cells causes mortality and multiorgan inflammation. (A) Longitudinal assessment of body weight change compared with weight at 10 weeks from 2 independent experiments. (B) Kaplan-Meier survival curve comparing reconstituted mice. The 18-week cutoff was selected based on 100% lethality in IPEX(DR1) mice by this time point in the first experimental cohort to compare variability across 2 independent experiments. Control(DR1) n = 10, IPEX(NSG) n = 10, IPEX(DR1) n = 19. (C) Human chimerism in spleen of reconstituted mice assessed by flow cytometry pooled from 2 experiments. Open circles are individual mice. Bars are the mean ± SEM. (D) Hematoxylin and eosin–stained sections from the lung, liver, small intestine (sm. int.), and colon of NSGAb°DR1 mice reconstituted with control bone marrow CD34⁺ HSCs or IPEX CD34⁺ HSCs, NSG mice reconstituted with IPEX CD34⁺ HSCs, and Foxp3^sf mice. Black arrowheads denote leukocyte infiltrate. Scale bars are 100 μm. Statistical analysis performed using 1-way ANOVA with Tukey’s multiple comparisons test (A,C), curve comparison using log-rank Mantel-Cox test (B). *P < .05, **P < .01.