Endothelial injury: cause and effect of alloimmune inflammation.

This review discusses the concept that endothelial cells may facilitate inflammation, but are also targets of the inflammatory response. Endothelial cells express several molecules that promote leukocyte recruitment, and other molecules, such as MHC class I that enable endothelial injury. Circulating alloantibodies produced following transplantation may also target the endothelium for injury. It has been shown that the expression of select protective genes within endothelial cells, including anti-apoptotic genes, may provide resistance to immune-mediated injury. Thus, an understanding of the mechanisms by which endothelial cells are injured and by which endothelial cells are protected is important for our understanding of allograft rejection.