Abstract
Neutrophil granulocytes (PMNs) adhere poorly to and are unable to locomote on collagen-coated glass; they are able to attach to and invade three-dimensional matrices of collagen fibres. Invasion is largely independent of adhesion to the fibres, does not occur by proteolysis of the gel, and is not affected by the presence of fibronectin or chondroitin sulphate. Invasion is reduced by increasing the concentration of collagen in the gel or by the presence of hyaluronic acid. It is proposed that in both these situations there is physical obstruction of PMN movement. The ability to locomote through tissues of very variable properties in vivo is important in the role of the PMN in inflammation.