Soluble ICAM-1 (sICAM-1) provokes PMN elastase release.
Elevated levels of soluble intercellular adhesion molecule-1 have been shown predictive of post-injury multiple organ failure. We hypothesized that sICAM-1 augments distant organ injury via its affect on the PMN and; thus, have examined neutrophil elastase and superoxide production in response to sICAM-1. To obtain soluble ICAM-1, Chinese Hamster Ovarian (CHO) cells were transfected with human ICAM-1 (cDNA vector CD1.8), lysed and centrifuged at 150,000g for 1 hr; supernatant was passed over an ICAM-1 affinity gradient, eluted with 0.1 mM glycine x HCl, and concentrated using an Amicon Spin-X filter. PMNs were incubated for 1 hr with sICAM-1 at 37 degrees C. Quiescent and PMA-activated PMNs served as negative and positive controls respectively. Elastase activity was measured by the cleavage of methoxy-succinyl-alalyl-alalyl-prolyl-valyl-p-nitroanilide. Superoxide production was determined by superoxide dismutase inhibitive ferricytochrome C reduction over a 5-60 min incubation. PMN incubation with sICAM-1 provoked marked increase in elastase release 10.43 +/- 2.90 (10(-6) U/hr) compared to control 1.64 +/- 0.57, and was equivalent to PMA-activated PMN elastase release 11.60 +/- 1.50 (10(-6) U/hr). In contrast, sICAM-1 alone did not promote spontaneous PMN superoxide production beyond buffer treated PMNs (0.25 +/- 0.09 nmole/2.5 x 10(5) PMN/min). In sum, sICAM-1 stimulates PMN elastase release in vitro. Clinically, this may represent a mechanism by which sICAM-1 participates in the genesis of post-injury multiple organ failure.
Barnett
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Department of Surgery, Denver General Hospital and the University of Colorado Health Sciences Center, USA.
Moore
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Moore
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Carl
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D000595:Amino Acid Sequence; D000818:Animals; D016466:CHO Cells; D002846:Chromatography, Affinity; D006224:Cricetinae; D004730:Endothelium, Vascular / Q000502:physiology; D006801:Humans; D066298:In Vitro Techniques; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis / Q000302:isolation & purification / Q000494:pharmacology*; D019272:Leukocyte Elastase; D008954:Models, Biological; D008969:Molecular Sequence Data; D009504:Neutrophils / Q000187:drug effects / Q000201:enzymology*; D010196:Pancreatic Elastase / Q000378:metabolism*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000302:isolation & purification / Q000494:pharmacology; D013379:Substrate Specificity; D013481:Superoxides / Q000097:blood; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014462:Ultrafiltration
D011994:Recombinant Proteins; D013481:Superoxides; D018799:Intercellular Adhesion Molecule-1; D010196:Pancreatic Elastase; D019272:Leukocyte Elastase; D013755:Tetradecanoylphorbol Acetate