Priming of polymorphonuclear leukocytes: a culprit in the initiation of endothelial cell injury

• Published in: American journal of physiology. Heart and circulatory physiology 2006-05, Vol.290 (5), p.H2051-H2058
• Main Authors: Jacobi, Jeanna, Sela, Shifra, Cohen, Hector I, Chezar, Judith, Kristal, Batya
• Format: Article
• Language: English
• Subjects: Cell Communication - immunology; Cells, Cultured; Coculture Techniques; Cytokines - immunology; Endothelial Cells - immunology; Endothelial Cells - pathology; Humans; Neutrophil Activation - immunology; Neutrophils - immunology; Neutrophils - pathology
• ISSN: 0363-6135; 1522-1539
• DOI: 10.1152/ajpheart.01040.2005

1 Eliachar Research Laboratory, 2 Pathology Laboratory, 3 Hematology Laboratory, and 4 Department of Nephrology and Hypertension, Western Galilee Hospital, Nahariya, and 5 Bruce Rappoport School of Medicine, Technion, Haifa, Israel Submitted 3 October 2005 ; accepted in final form 23 December 2005 Peripheral polymorphonuclear leukocytes (PMNL) in hemodialysis (HD) patients are primed, continually releasing and exposing the vascular endothelium to soluble factors such as reactive oxygen species and inflammatory mediators. To mimic the close proximity between PMNL and the endothelial monolayer and to monitor and characterize the influence of soluble mediators released from PMNL, we developed a novel cocultivation system using primary human umbilical vein endothelial cell (HUVEC) cultures and PMNL, with a sieve separating the two cell types to prevent direct adhesive effects. PMNL (10 6 ) from HD patients or from healthy normal controls were cocultivated with HUVEC (10 5 ) for 15 min, and endothelial cell injury was assessed by HUVEC morphology, cell detachment, and apoptosis. Proinflammatory changes were estimated by expression of HUVEC adhesion molecule P-selectin and by endothelial IL-8 and endothelial nitric oxide synthase mRNA. The levels of intracellular tissue factor reflected the procoagulant state, whereas NADPH oxidase activity served as an indicator for prooxidative changes in HUVEC. Mediators released from the primed PMNL triggered activation/dysfunction of endothelial cells, causing 1 ) an increase in endothelial cell detachment and apoptosis, 2 ) a proinflammatory state manifested by increased IL-8 mRNA expression and P-selectin on the endothelial surface, 3 ) activation of endothelial NADPH oxidase, 4 ) an increase in endothelial cell tissue factor that directly correlated with PMNL priming index, and 5 ) a decrease in endothelial nitric oxide synthase mRNA. Our data support a pathogenic link between PMNL priming and endothelial dysfunction, suggesting that PMNL priming is a potential new nontraditional risk factor for the development of atherosclerosis. cocultivation; nicotinamide adenine dinucleotide phosphate oxidase; polymorphonuclear leukocyte priming index Address for reprint requests and other correspondence: S. Sela, Eliachar Research and Microbiology Laboratories, Western Galilee Hospital, Nahariya Medical Center, Nahariya 22100, Israel (e-mail: Shifra.Sela{at}naharia.health.gov.il )