Garcia-Castillo, Maria DanielaChinnapen, Daniel J-Fte Welscher, Yvonne MGonzalez, RodrigoSoftic, SamirPacheco, MicheleMrsny, Randall JKahn, C Ronaldvon Andrian-Werburg, UlrichLau, JesperPentelute, Bradley LLencer, Wayne2018-07-252018Garcia-Castillo, M. D., D. J. Chinnapen, Y. M. te Welscher, R. J. Gonzalez, S. Softic, M. Pacheco, R. J. Mrsny, et al. 2018. “Mucosal absorption of therapeutic peptides by harnessing the endogenous sorting of glycosphingolipids.” eLife 7 (1): e34469. doi:10.7554/eLife.34469. http://dx.doi.org/10.7554/eLife.34469.http://nrs.harvard.edu/urn-3:HUL.InstRepos:37298259Transport of biologically active molecules across tight epithelial barriers is a major challenge preventing therapeutic peptides from oral drug delivery. Here, we identify a set of synthetic glycosphingolipids that harness the endogenous process of intracellular lipid-sorting to enable mucosal absorption of the incretin hormone GLP-1. Peptide cargoes covalently fused to glycosphingolipids with ceramide domains containing C6:0 or smaller fatty acids were transported with 20-100-fold greater efficiency across epithelial barriers in vitro and in vivo. This was explained by structure-function of the ceramide domain in intracellular sorting and by the affinity of the glycosphingolipid species for insertion into and retention in cell membranes. In mice, GLP-1 fused to short-chain glycosphingolipids was rapidly and systemically absorbed after gastric gavage to affect glucose tolerance with serum bioavailability comparable to intraperitoneal injection of GLP-1 alone. This is unprecedented for mucosal absorption of therapeutic peptides, and defines a technology with many other clinical applications.en-USglycolipids/gangliosideslipid sortingdrug deliveryGLP-1/ diabetesmembrane transportepithelial cellsMouseJournal Article2018-07-2510.7554/eLife.34469