148646 20260418110657.0 doi 10.1172/jci.insight.181481 sideral 141885 ART-2025-141885 eng Layunta, Elena Universidad de Zaragoza (orcid)0000-0001-5573-6144 MUC17 is an essential small intestinal glycocalyx component that is disrupted in Crohn’s disease 2025 Access copy available to the general public Unrestricted Crohn's disease (CD) is the chronic inflammation of the terminal ileum and colon triggered by a dysregulated immune response to bacteria, but insights into specific molecular perturbations at the critical bacteria-epithelium interface are limited. Here we report that the membrane mucin MUC17 protected small intestinal enterocytes against commensal and pathogenic bacteria. In non-inflamed CD ileum, reduced MUC17 levels and a compromised glycocalyx barrier allowed recurrent bacterial contact with enterocytes. Muc17 deletion in mice rendered the small intestine particularly prone to atypical bacterial infection while maintaining resistance to colitis. The loss of Muc17 resulted in spontaneous deterioration of epithelial homeostasis and in the extra-intestinal translocation of bacteria. Finally, Muc17-deficient mice harbored specific small intestinal bacterial taxa observed in CD patients. Our findings highlight MUC17 as an essential regiospecific line of defense in the small intestine with relevance for early epithelial defects in CD. info:eu-repo/semantics/openAccess by https://creativecommons.org/licenses/by/4.0/deed.es 6.1 2024 MEDICINE, RESEARCH & EXPERIMENTAL 34 / 195 = 0.174 2024 Q1 T1 2.917 2024 Medicine (miscellaneous) 2024 Q1 11.5 2024 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Jäverfelt, Sofia van de Koolwijk, Fleur C. Sivertsson, Molly Dolan, Brendan Arike, Liisa Thulin, Sara I.M. Vallance, Bruce A. Pelaseyed, Thaher 1001 025 Universidad de Zaragoza Dpto. Anatom.,Embri.Genét.Ani. Área Anatom.Anatom.Patológ.Com 10, 3 (2025), 181481e [16 pp.] JCI insight JCI insight 2379-3708 9492777 http://zaguan.unizar.es/record/148646/files/texto_completo.pdf Versión publicada 958016 http://zaguan.unizar.es/record/148646/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:148646 articulos driver 2026-04-18-11:05:07 ARTICLE