NSP4, an elastase-related protease in human neutrophils with arginine specificity

NSP4 is stored in azurophil granules and released by activated neutrophils as active endoprotease with restricted specificity.

Whereas neutrophil elastase, cathepsin G, and proteinase 3 have been known as granule-associated serine proteases of neutrophils for decades, a fourth member, called neutrophil serine protease 4 (NSP4), was just recently described and provisionally characterized. In this study, we identified NSP4 as a novel azurophil granule protein of neutrophils by Western blot analyses of subcellular fractio...

PEGylated substrates of NSP4 protease: A tool to study protease specificity

Herein we present the synthesis of a novel type of peptidomimetics composed of repeating diaminopropionic acid residues modified with structurally diverse heterobifunctional polyethylene glycol chains (abbreviated as DAPEG). Based on the developed compounds, a library of fluorogenic substrates was synthesized. Further library deconvolution towards human neutrophil serine protease 4 (NSP4) yield...

Inhibition of neutrophil elastase by alpha1-protease inhibitor at the surface of human polymorphonuclear neutrophils.

The uncontrolled proteolytic activity in lung secretions during lung inflammatory diseases might be due to the resistance of membrane-bound proteases to inhibition. We have used a new fluorogenic neutrophil elastase substrate to measure the activity of free and membrane-bound human neutrophil elastase (HNE) in the presence of alpha1-protease inhibitor (alpha1-Pi), the main physiological inhibit...

Inhibition of Neutrophil Elastase by 1-Protease Inhibitor at the Surface of Human Polymorphonuclear Neutrophils

Elastase inhibitor. Characterization of the human elastase inhibitor molecule associated with monocytes, macrophages, and neutrophils

A fast-acting inhibitor of serine elastase has been detected at high levels in human neutrophils, fresh monocytes, matured monocytes, and macrophages. The elastase inhibitor was isolated from large scale cultures of the monocyte-like cell line U937 by DNase chromatography, disulfide exchange, Phenyl-Sepharose, Red A-agarose, and DEAE HPLC chromatography with an average yield of 480 micrograms f...