Title

Regulation of P-selectin binding to the neutrophil P-selectin counter-receptor P-selectin glycoprotein ligand-1 by neutrophil elastase and cathepsin G

UMMS Affiliation

Department of Pediatrics

Date

9-1-2001

Document Type

Article

Medical Subject Headings

Amino Acid Sequence; Autocrine Communication; Cathepsin G; Cathepsins; Humans; Inflammation; Leukocyte Elastase; Membrane Glycoproteins; Metalloendopeptidases; Molecular Sequence Data; Neutrophils; P-Selectin; Platelet Glycoprotein GPIb-IX Complex; Protein Binding; Serine Endopeptidases

Disciplines

Hematology | Oncology | Pediatrics

Abstract

In the inflammatory response, leukocyte rolling before adhesion and transmigration through the blood vessel wall is mediated by specific cell surface adhesion receptors. Neutrophil rolling involves the interaction of P-selectin expressed on activated endothelium and its counter-receptor on neutrophils, P-selectin glycoprotein ligand-1 (PSGL-1). Here, it is reported that P-selectin binding to neutrophils is lost under conditions that cause the release of proteinases from neutrophil primary granules. Treatment of neutrophils with the purified neutrophil granule proteinases, cathepsin G and elastase, rapidly abolished their capacity to bind P-selectin. This inactivation corresponded to loss of the N-terminal domain of PSGL-1, as assessed by Western blot analysis. A loss of intact PSGL-1 protein from the surfaces of neutrophils after the induction of degranulation was also detected by Western blot analysis. Cathepsin G initially cleaved near the PSGL-1 N-terminus, whereas neutrophil elastase predominantly cleaved at a more C-terminal site within the protein mucin core. Consistent with this, cathepsin G cleaved a synthetic peptide based on the PSGL-1 N-terminus between Tyr-7/Leu-8. Under conditions producing neutrophil degranulation in incubations containing mixtures of platelets and neutrophils, the loss of PSGL-1, but not P-selectin, from platelet-neutrophil lysates was detected. Cathepsin G- or neutrophil elastase-mediated PSGL-1 proteolysis may constitute a potential autocrine mechanism for down-regulation of neutrophil adhesion to P-selectin.

Rights and Permissions

Citation: Blood. 2001 Sep 1;98(5):1440-7. doi 10.1182/blood.V98.5.1440

Related Resources

Link to article in PubMed

PubMed ID

11520793