Properties of Lipoproteins Responsible for High Affinity Binding to Cell Surface Receptors of Fibroblasts and Smooth Muscle Cells

Abstract

Our studies of cholesterol-induced hyperlipoproteinemia in various animal models have led to the identification of several unique lipoproteins. This discovery has provided an opportunity to explore the properties responsible for the binding of certain lipoproteins to cell surface receptors of cultured fibroblasts and arterial smooth muscle cells. After a brief description of the types of plasma lipoproteins used in these studies, we will present data to support the following conclusions: a) that specificity for lipoprotein binding to the high affinity receptor sites resides with the apoproteins; b) that either the B or the arginine-rich apoprotein (ARP) is responsible for this binding; c) that a similar stereospecific charged region or recognition site may be shared in common by the B and ARP; and d) that theARP-containing lipoproteins are more avidly bound to the receptor than are the apo-B-containing lipoproteins.