Elastase human neutrophils

Protease from the class of serine proteases (hydrolases, peptidases). Other serine proteases are proteinase 3 (PR3) and cathepsin G. The neutrophil elastase or granulocyte elastase is a 30 kDa glycoprotein consisting of a single peptide chain with 218 amino acids and 4 disulfide bridges. It is formed by neutrophil granulocytes and their precursor cells.

The biological functions are not yet completely clear. Enzymatic function exists in the degradation of elastin and other scleroproteins, e.g., collagen types I, II, III, IV, VIII, IX, X, and XI, structural glycoproteins, and in the degradation of fibronectin, laminin, and proteoglycans. Furthermore, neutrophil elastase also indirectly stimulates the degradation of extracellular matrix proteins.

Other functions of serine proteases are primarily for defense against microbial pathogens. Physiological counterparts are alpha1-antitrypsin and alpha2-macroglobulin. If the amount of alpha1-antitrypsin is insufficient, elastase has a destructive effect (e.g., in emphysema).

Other diseases in which neutrophil elastase seems to play an important role are cystic fibrosis, shock lung (ARDS: adult respiratory distress syndrome), rheumatoid arthritis and infectious diseases.

1. Gehrig S et al (2014) Lack of neutrophil elastase reducesinflammation
   , mucus hypersecretion, and emphysema, but not mucus obstruction, in mice with cystic fibrosis-like lung disease. On J Respir Crit Care Med 189:1082-1092.

2. Tang FS et al (2015) Altered Innate Immune Responses in Neutrophils from Patients with Well- and Suboptimally Controlled Asthma. Mediators Inflamm doi: 10.1155/2015/219374.