These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Neutrophil-mediated injury to endothelial cells. Enhancement by endotoxin and essential role of neutrophil elastase.
    Author: Smedly LA, Tonnesen MG, Sandhaus RA, Haslett C, Guthrie LA, Johnston RB, Henson PM, Worthen GS.
    Journal: J Clin Invest; 1986 Apr; 77(4):1233-43. PubMed ID: 3485659.
    Abstract:
    The neutrophil has been implicated as an important mediator of vascular injury, especially after endotoxemia. This study examines neutrophil-mediated injury to human microvascular endothelial cells in vitro. We found that neutrophils stimulated by formyl-methionyl-leucyl-phenylalanine (FMLP), the complement fragment C5a, or lipopolysaccharide (LPS) (1-1,000 ng/ml) alone produced minimal endothelial injury over a 4-h assay. In contrast, neutrophils incubated with endothelial cells in the presence of low concentrations of LPS (1-10 ng/ml) could then be stimulated by FMLP or C5a to produce marked endothelial injury. Injury was maximal at concentrations of 100 ng/ml LPS and 10(-7) M FMLP. Pretreatment of neutrophils with LPS resulted in a similar degree of injury, suggesting that LPS effects were largely on the neutrophil. Endothelial cell injury produced by LPS-exposed, FMLP-stimulated neutrophils had a time course similar to that induced by the addition of purified human neutrophil elastase, and different from that induced by hydrogen peroxide (H2O2). Further, neutrophil-mediated injury was not inhibited by scavengers of a variety of oxygen radical species, and occurred with neutrophils from a patient with chronic granulomatous disease, which produced no H2O2. In contrast, the specific serine elastase inhibitor methoxy-succinyl-alanyl-alanyl-prolyl-valyl-chloromethyl ketone inhibited 63% of the neutrophil-mediated injury and 64% of the neutrophil elastase-induced injury. However, neutrophil-mediated injury was not inhibited significantly by 50% serum, 50% plasma, or purified alpha 1 proteinase inhibitor. These results suggest that, in this system, chemotactic factor-stimulated human neutrophil injury of microvascular endothelial cells is enhanced by small amounts of LPS and may be mediated in large part by the action of neutrophil elastase.
    [Abstract] [Full Text] [Related] [New Search]