Evidence for an interaction of lipoprotein lipase with artery wall proteoglycans

1. Artery wall proteoglycans-lipoprotein lipase binding characteristics were studied using bovine milk 125I-labelled lipoprotein lipase (LPL) and chondroitin sulphate-dermatan sulphate proteoglycans (PGs) purified from pig aorta. 2. The binding process was studied either by a soluble assay (gel filtration) or by an immobilized proteoglycan assay (ELISA). 3. The binding process was reversible, saturable and occurred at a stoichiometry 1:1. 4. The binding process involved ionic interactions between the positively charged groups of LPL and the negatively charged groups of PG carbohydrate chains. 5. The complex PG-LPL may lead to the production of remnant lipoproteins and, thereby, contribute to cholesteryl ester accumulation in the arterial wall.