Heparin and heparan sulphate are inhibitors of human leucocyte elastase

Abstract

1. Heparin and heparan sulphate strongly inhibited human leucocyte elastase activity in an automated assay using the soluble substrate, n-succinyl-(L-alanine)3-p-nitroanilide (50% inhibition of 250 microliters of 10 micrograms of human leucocyte elastase/ml was obtained with 80 microliters of 2.8 micrograms of heparin/ml and 8 micrograms of heparan sulphate/ml). Less significant inhibition at the same concentrations was seen with the other glycosaminoglycans tested: hyaluronic acid and chondroitin sulphates A-C. 2. Heparin and heparan sulphate also strongly inhibited human leucocyte elastase activity towards insoluble human lung elastin, as determined by an e.l.i.s.a. for soluble elastin-derived peptides released by elastolytic activity on the elastin. This inhibition was shown not to be due to a direct interference of the glycosaminoglycans in the e.l.i.s.a. nor to the inhibition causing a change in the size of the elastin-derived peptides. However, unlike the chromogenic assay with n-succinyl-(L-alanine)3-p-nitroanilide as substrate, where heparin was the more effective inhibitor, in this assay system heparan sulphate was the more effective inhibitor (50% inhibition of 100 microliters of 50 ng of human leucocyte elastase/ml was obtained with 100 microliters of 4.5 micrograms of heparin/ml and 0.8 microgram of heparan sulphate/ml). These results suggest that heparin and heparan sulphate, as components of cellular and basement membranes, are likely to have a role in protecting structural proteins, such as elastin, from the proteolytic activity of human leucocyte elastase.(ABSTRACT TRUNCATED AT 250 WORDS)

Neutrophil elastase depends on serglycin proteoglycan for localization in granules

“…This is in line with the stronger binding and inhibition of neutrophil elastase by heparin compared with chondroitin sulfate in vitro. [46][47][48] In cytotoxic lymphocytes, like in neutrophils, serglycin has chondroitin sulfate side chains attached, and only a single granule protein has been found to be dependent on serglycin for proper localization here, 7 indicating that selectivity in serglycin-mediated localization in granules is associated with the nature of glycosaminoglycan side chains.…”

The effects of heparin on the adhesion of human peripheral blood mononuclear cells to human stimulated umbilical vein endothelial cells

“…However, a possible immunomodulatory function is suggested, as increasing evidence, both experimental and clinical, indicates heparin to possess a range of anti-in¯ammatory properties (reviewed by Jaques, 1979;Tyrrell et al, 1999). Many of these e ects may be mediated through the ability of this large, negatively charged molecule to bind and inactivate an array of in¯ammatory proteins, including certain complement components (Matzner et al, 1984;Strunk & Colten, 1976), chemokines (Miller & Krangel, 1992) and products of activated granulocytes (Fredens et al, 1991;Redini et al, 1988;Walsh et al, 1991b) as well as thrombin, a known proin¯ammatory mediator which acts through PAR-1 receptor activation. In addition, heparin is known to bind a number of adhesion molecules involved in leucocyte tra cking into tissues, including mac-1 (CD11b/CD18; Diamond et al, 1995) and L-selectin (Koenig et al, 1998) on in¯ammatory cells and the endothelial adhesion molecules P-selectin (Revelle et al, 1996;Skinner et al, 1991) and platelet endothelial adhesion molecule-1 (PECAM-1; Watt et al, 1993).…”

Immunocytochemical evidence for extra-cellular initiation of elastase-induced bronchial secretory cell metaplasia in hamsters

“…HNE is a basic glycoprotein [24] and mucin, which is negatively charged due to its content of sialic acid and sulphate groups, is a target for enzymatic degradation by HNE [25]. The possibility that HNE may be rendered immunologically negative by surface-associated mucus [26], or by sulphated glycoconjugates [27,28], cannot be ruled out.…”