Abstract
Cell migration across epithelial barriers occurs in diverse developmental, immunological, and pathological contexts. Here, we investigate the contribution of heterotypic adhesion between migrating cells and epithelial "substrate" cells to transepithelial migration. Using an in silico model inspired by the migration of primordial germ cells across the midgut epithelium in the Drosophila embryo, we show that heterotypic adhesion modulates migration efficiency in a nonmonotonic manner, revealing the existence of an optimal adhesion regime. Consistent with this prediction, in vivo overexpression of E-cadherin in germ cells accelerated their exit from the midgut relative to controls. Beyond providing experimentally testable predictions, our model integrates and explains previous observations on the role of heterotypic adhesion in cell-on-cell migration, offering a framework for understanding transepithelial migration across biological contexts.
