Endothelial cell apoptosis in sepsis.

OBJECTIVE: To discuss a potential role for endothelial cell apoptosis in the pathogenesis of sepsis. DATA SOURCES: Studies published in biomedical journals and studies from the authors' laboratory. STUDY SELECTION: In vitro and in vivo studies of endothelial cell apoptosis in endotoxin and sepsis models. DATA EXTRACTION AND SYNTHESIS: Relevant studies that investigate the role of apoptosis in endotoxemia and sepsis are presented. The divergent results of the different studies and the potential reasons for the discrepant findings are presented. The importance of apoptosis in sepsis and the potential impact on endothelial cells and organ function are highlighted.
CONCLUSIONS: Apoptosis is an important mechanism of lymphocyte and gastrointestinal epithelial cell death in sepsis. Although abundant in vitro studies indicate that endothelial cell apoptosis can occur in response to certain pathogenic organisms (e.g., Rickettsia rickettsii), data documenting endothelial cell apoptosis in in vivo models of sepsis are lacking. Because endothelial cells that undergo apoptosis detach from the vessel basement membrane, enter the circulation, and are rapidly cleared, it may be difficult to detect endothelial cell apoptosis in in vivo models of sepsis. The impact of endothelial cell apoptosis in sepsis may either be detrimental or beneficial to host survival, depending on the particular pathogen.