Fig. 1

Spontaneous colitis development in aged C57BL/6 mice with conditional depletion of Rabgef1 in IECs (i.e., Rabgef1^IEC-KO mice). a Representative RABGEF1 staining of colon sections from 8-week-old WT C57BL/6 mice. Pictures are representative of 1 of >6 mice analyzed, each of which gave similar results. b Efficiency and specificity of Cre-mediated Rabgef1 exon 3 deletion assessed by quantitative PCR in CD45⁺EpCAM⁻ leukocytes and CD45⁻EpCAM⁺ IECs. c, d Representative hematoxylin & eosin (H&E, top panels) and Periodic Acid Schiff (PAS, bottom panels) stainings of colon sections from 12-month-old Rabgef1^IEC-KO and littermate controls. Asterisks indicate inflammatory cell infiltrates and arrowhead shows eroded epithelial areas. e Colon histopathological score (n = 10–12 mice/group). b, e Data are shown as mean + SEM, as well as individual values, and are pooled from 2 (b) or >3 (e) independent experiments. P values were calculated using a one-way ANOVA with Tukey’s post hoc tests (b) and a Mann–Whitney test (e). ^***P < 0.001. Scale bars: 100 μm (a, c); 20 μm (d). WT wild-type