Resumen: The intestine is under constant exposure to chemicals, antigens, and microorganisms from the external environment. Apical aspects of transporting epithelial cells (enterocytes) form a brush-border membrane (BBM), shaped by packed microvilli coated with a dense glycocalyx. We present evidence showing that the glycocalyx forms an epithelial barrier that prevents exogenous molecules and live bacteria from gaining access to BBM. We use a multi-omics approach to investigate the function and regulation of membrane mucins exposed on the BBM during postnatal development of the mouse small intestine. Muc17 is identified as a major membrane mucin in the glycocalyx that is specifically upregulated by IL-22 as part of an epithelial defense repertoire during weaning. High levels of IL-22 at time of weaning reprogram neonatal postmitotic progenitor enterocytes to differentiate into Muc17-expressing enterocytes, as found in the adult intestine during homeostasis. Our findings propose a role for Muc17 in epithelial barrier function in the small intestine. Idioma: Inglés DOI: 10.1016/j.celrep.2021.108757 Año: 2021 Publicado en: Cell Reports 34, 7 (2021), 108757 [24 pp.] ISSN: 2211-1247 Factor impacto JCR: 9.995 (2021) Categ. JCR: CELL BIOLOGY rank: 33 / 195 = 0.169 (2021) - Q1 - T1 Factor impacto CITESCORE: 15.1 - Biochemistry, Genetics and Molecular Biology (Q1)