Endothelial cell polarization during lumen formation, tubulogenesis, and vessel maturation in 3D extracellular matrices

摘要: A fundamental event during vascular morphogenesis is the formation of endothelial cell (EC) lumens and tube networks in 3D extracellular matrices (ECM). This morphogenic step leads to rapid EC polarization in that apical and basal membrane domains are created, with fluid contacting the developing apical membrane surface, while ECM is in contact with the basal membrane surface. Interestingly, it has been difficult to identify specific apical vs. basal markers in ECs. This suggests that their ability to polarize is distinct from other cell types such as epithelial cells which have more extensive cell–cell junctional contacts and more specialized apical domains with exocrine abilities where substantial fluids can be generated and released apically. One key difference is that ECs in contact with blood must be flat in order to properly function and respond to fluid flow forces. Interestingly, our recent studies reveal that …