The chemotactic properties of cartilage glycosaminoglycans for polymorphonuclear neutrophils

Cartilage breakdown products have been tested for their effects on the locomotion of rat polymorphonuclear neutrophils in vitro. Chondroitin sulphate, keratan sulphate and hyaluronic acid were used in checkerboard migration assays to differentiate chemotaxis from chemokinesis. All test substances showed both chemokinetic and chemotactic activities. The same substances were then injected intradermally to determine their effects on vascular permeability and leukocyte accumulation in vivo. There was no significant effect on vascular permeability 30 minutes after injection as measured by a dye-leakage method. Histological examination of skin sections taken 6 hours after injection showed modest accumulations of polymorphonuclear neutrophils. It is suggested that cartilage breakdown products may account for the persistence of polymorphonuclear neutrophils in some chronic inflammatory joint diseases.