Proteolytic Cleavage of ICAM-1 by Human Neutrophil Elastase

Human leukocyte elastase (HLE) participates in tissue destruction in a number of inflammatory disorders, including rheumatoid arthritis and cystic fibrosis. Since HLE has been shown to bind to Mac-1, and ICAM-1 plays a key role during the recruitment and the activation of leukocytes at inflamed site...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of immunology (1950) 1998-12, Vol.161 (11), p.6398-6405
Main Authors: Champagne, Benoit, Tremblay, Pierre, Cantin, Andre, St. Pierre, Yves
Format: Article
Language:English
Subjects:
Adolescent
Adult
Female
Humans
Hydrolysis
Intercellular Adhesion Molecule-1 - isolation & purification
Intercellular Adhesion Molecule-1 - metabolism
Leukocyte Elastase - metabolism
Male
Protein Processing, Post-Translational - immunology
Solubility
Sputum - enzymology
U937 Cells
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Human leukocyte elastase (HLE) participates in tissue destruction in a number of inflammatory disorders, including rheumatoid arthritis and cystic fibrosis. Since HLE has been shown to bind to Mac-1, and ICAM-1 plays a key role during the recruitment and the activation of leukocytes at inflamed sites, we investigated the capacity of HLE to cleave ICAM-1. Flow-cytometric analyses showed a dose-dependent cleavage of ICAM-1 by HLE on different human cell lines. The cleavage was completely inhibited by alpha1-antitrypsin, a natural HLE protease inhibitor. The ability of HLE to degrade ICAM-1 was further confirmed by electrophoretic analysis using a soluble form of ICAM-1 (D1-D5). Enzymatic removal of N-linked glycosylation did not significantly modulate ICAM-1 cleavage by HLE, while removal of sialic acid residues partially reduced the sensitivity of ICAM-1 to HLE. We further showed that sputum of cystic fibrosis patients contains high levels of HLE activity capable of cleavage of cell surface ICAM-1. The cleavage induced by incubation of cells with the sputum sample was totally inhibited by alpha1-antitrypsin and the specific peptidic HLE inhibitor N-methoxysuccinyl-Ala-Ala-Pro-Val-chloromethylketone. Moreover, the cleavage of ICAM-1 was concomitant to that of CD4 at the surface of the same cell, at the same amplitude, and at all HLE concentrations. The capacity of HLE to modulate the expression of ICAM-1 on the surface of leukocytes by proteolytic cleavage brings support to the hypothesis that overproduction of HLE can cause severe immunologic lung disorders by affecting intercellular adhesion.
ISSN:0022-1767
1550-6606
DOI:10.4049/jimmunol.161.11.6398