JCI insight JCI insight MUC17 is an essential small intestinal glycocalyx component that is disrupted in Crohn’s disease Layunta Elena Universidad de Zaragoza Jäverfelt Sofia van de Koolwijk Fleur C. Sivertsson Molly Dolan Brendan Arike Liisa Thulin Sara I.M. Vallance Bruce A. Pelaseyed Thaher 2025 research-article