Mechanical Intercellular Communication via Matrix-Borne Cell Force Transmission During Vascular Network Formation.

Intercellular communication is critical to the formation and homeostatic function of all tissues. Previous work has shown that cells can communicate mechanically via the transmission of cell-generated forces through their surrounding extracellular matrix, but this process is not well understood. Here, mechanically defined, synthetic electrospun fibrous matrices are utilized in conjunction with a microfabrication-based cell patterning approach to examine mechanical intercellular communication (MIC) between endothelial cells (ECs) during their assembly into interconnected multicellular networks. It is found that cell force-mediated matrix displacements in deformable fibrous matrices underly directional extension and migration of neighboring ECs toward each other prior to the formation of stable cell-cell connections enriched with vascular endothelial cadherin (VE-cadherin). A critical role is also identified for calcium signaling mediated by focal adhesion kinase and mechanosensitive ion channels in MIC that extends to multicellular assembly of 3D vessel-like networks when ECs are embedded within fibrin hydrogels. These results illustrate a role for cell-generated forces and ECM mechanical properties in multicellular assembly of capillary-like EC networks and motivates the design of biomaterials that promote MIC for vascular tissue engineering.