VASCULAR ENDOTHELIAL CADHERIN AND ROLE IN (VE-CADHERIN) - CLONING ENDOTHELIAL CELL-CELL ADHESION

Objective: To identify proteins responsible for intercellular junction integrity in human umbilical vein endothelial cells (HUVEC), we produ ced a monoclonal antibody that recognized an endothelial cell-specific , junctionally restricted protein. We characterized and cloned the ant igen to study its functional properties. Methods: Tile size and cellul ar distribution of the antigen were determined by immunofluorescence a nd immunoprecipitation. The molecule was cloned and transfected into c ell Lines, and its role in cell-cell adhesion and growth rate was dete rmined. Results: Monoclonal antibody heel recognizes VE-cadherin, an e ndothelial cell-restricted cell adhesion molecule. VE-cadherin is loca lized to the borders between apposing endothelial cells but is diffuse ly distributed on subconfluent or migrating cells. Transfection of fib roblasts with VE-cadherin imparts to them the ability to adhere to eac h other in a calcium-dependent hemophilic manner. Expression of VE-cad herin over a several-log range does not change the growth rate of thes e cells. Conclusions: Despite the fact that VE cadherin is a ''nonclas sical'' cadherin by structure, it functions as a classic cadherin by i mparting to cells the ability to adhere in a calcium-dependent, homoph ilic manner. On HUVEC it appears to play a role in maintaining monolay er integrity.