The effect of human neutrophil elastase and cathepsin G on the collagen of cartilage, tendon, and cornea.

The degradation of collagen in a number of inflammatory diseases is associated with infiltration of the tissues by neutrophil leucocytes. The neutrophil serine proteinases, elastase and cathepsin G, solubilize type II collagen from articular cartilage by an attack on the terminal peptides, destroying the inter- and intra-molecular crosslinks. Both enzymes also solubilize type IV collagen from kidney basement membrane. Elastase attacks the terminal peptides of type I collagen of tendon, cornea and skin, and also attacks the helical region of type I skin collagen. It seems probable that the neutrophil proteinases play an important role in collagen degradation in vivo in a variety of pathological conditions.