Dysfunctional intestinal microvascular endothelial cells: Insights and therapeutic implications in gastrointestinal inflammation.

The intestinal microvascular endothelium plays a crucial role in orchestrating host responses to inflammation within the gastrointestinal tract. This review delves into the unique aspects of intestinal microvascular endothelial cells, distinct from those of larger vessels, in mediating leukocyte recruitment, maintaining barrier integrity, and regulating angiogenesis during inflammation. Specifically, their role in the pathogenesis of inflammatory bowel diseases, where dysregulated endothelial functions contribute to the disease progression, is reviewed. Furthermore, this review discusses the isolation technique for these cells and commonly used adhesion molecules for in vitro and in vivo experiments. In addition, we reviewed the development and therapeutic implications of a biologic agent targeting the interaction between α₄β₇ integrin on T lymphocytes and mucosal addressin cellular adhesion molecule-1 on gut endothelium. Notably, vedolizumab, a humanized monoclonal antibody against α₄β₇ integrin, has shown promising outcomes in inflammatory bowel diseases and other gastrointestinal inflammatory conditions, including chronic pouchitis, immune checkpoint inhibitor-induced colitis, and acute cellular rejection post-intestinal transplantation.