Fig 1: H&E staining, endoscopic views and IHC validation of APCDD1 overexpression in pediatric CD lesion sites (a) H&E staining of control and CD samples (magnification ×400, scale bar = 25 μm). (b) Endoscopic views of control and CD groups. (c) Expression of APCDD1 in control and CD samples (n = 5, magnification ×400, scale bar = 25 μm). (d) Quantification of APCDD1 expression in healthy control and CD samples. Case1: terminal ileum; Case2: duodenal bulb; Case3: terminal ileum; Case4: descending colon; Case5: terminal ileum; Case6: descending colon. ***, p < 0.001.