Warner-Lambert/Parke-Davis award lecture. Cytokine-mediated activation of vascular endothelium. Physiology and pathology.

The concept of endothelial cell activation has been extremely useful in understanding endothelial cell function. The morphologic definition of activation from the 1960s has been replaced by a cell biologic definition in the 1980s, but recent studies have suggested that these phenomena are two aspects of the same processes. Moreover, the initial distinction of endothelial cell activation, a beneficial reaction, from injury and dysfunction, a harmful sequence, has become more complex as clinical studies have revealed that activation can produce dysfunction, with or without injury. Most importantly, as our in vivo studies indicate, the concept of activation is a testable hypothesis, as modern immunochemical and molecular biologic techniques have been employed to bridge the gap between in vitro culture experiments and patient-based clinical research.