A Model for Epithelial Migration and Wound Healing in the Avian Embryo

It is increasingly clear that (collective) migration of epithelia plays an important role in morphogenesis and wound healing [6]. One of the interesting phenomena about epithelial migration is that the leading edge of the epithelia displays characteristics of both epithelia and cells undergoing EMT (epithelial-to-mesenchymal transition), so-called “partial” EMT. Developmental models in Drosophila and zebrafish have become important for studying signaling pathways involved in epithelial migration in recent years, but it is difficult to study the biomechanics of these systems. [2] Here, we revisit a little-used developmental model originally characterized by Chernoff [3] over two decades ago, which uses the area opaca (AO) of the chick embryo, an extraembryonic epithelium in birds which normally functions to spread across and encompass the nutritive yolk in a process called epiboly. We believe this model will be useful for studying epithelial migration because it is easily accessible and can be separated from the embryo to control the biomechanical environment.