ERAdP conditional KO mice exhibits loss of DCVs and impaired antibacterial ability. (A) Cross strategy of Vil-Cre and Cnep1r1^fl/fl mice. (B) DNA electrophoresis for loxP and Vil-Cre knock-in validation. (C)Cnep1r1 FISH of SI and colon of WT and Cnep1r1^ΔIEC mice. Red: Cnep1r1 probes; blue: DAPI. Scale bar: 70 μm. (D) Diagram of four patterns of Paneth cells normal (D₀), disordered (D₁), depleted (D₂), and diffuse (D₃). (E–I) Quantification of DCV numbers per Paneth cell (E), goblet cells per villus (F), ISC per crypt (G), Ki67⁺ cells per crypt (H), and Lyz⁺ puncta per crypt (I) of WT and Cnep1r1^ΔIEC mice (n = 6 mice for each group). (J) Immunofluorescence staining of ileums from littermate WT and Cnep1r1^ΔIEC mice. Red: lysozyme, green: WGA, and blue: DAPI. Scale bar: 20 μm. (K) Western blot for lysozyme and DEFA5 of ileal intestinal mucus layer. The intestinal contents from a 5-cm ileal segment were flushed with GuHCl and scraped using glass slides, followed by supernatant collection for western blot analysis. TFF3 secreted by goblet cells was used as a loading control. (L) AMP expression analysis with RNAseq of Cnep1r1^ΔIEC versus WT mice. (M) qPCR detection of ileal luminal commensal bacteria classified by phylum (n = 6 mice for each group). (N) Schematic diagram of S. Typhimurium stimulation and detection. Data in E–I and M are shown as means ± SEM; significance was determined by unpaired two-tailed Student’s t test (^*P < 0.05; ***P < 0.001; ns, not significant). Data in B, C, and E–M are representative of at least three independent experiments. Source data are available for this figure: SourceData FS2.