Evaluating integrin function in models of angiogenesis and vascular permeability.

All vascular biological processes are influenced to some degree by integrins expressed on endothelial cells, vascular smooth muscle cells, fibroblasts, platelets, or other circulating cells. In particular, angiogenesis requires cells to process signals from their microenvironment and respond by altering their cell-cell and cell-matrix adhesion, events which allow migration and vascular remodeling over the period of days to weeks. On the other hand, endothelial cells can respond to a permeability stimulus and alter their junctional adhesion molecules or vesicular transport machinery within seconds or minutes. This chapter will discuss the current understanding of how integrins participate in these processes, and explore the in vitro and in vivo models available to study the role of integrin function during angiogenesis and vascular leak.