Stimulation of arterial smooth muscle cell proliferation by remnant lipoprotein particles isolated by immuno-affinity chromatography with anti-apo A-I and anti-apo B-100.

Postprandial lipidemia, characterized by high plasma triglyceride-rich lipoprotein remnants, is associated with atherosclerosis. It has also been known that proliferation of vascular smooth muscle cells is crucial for the development of atherosclerosis. In this study, we investigated the direct effect of remnant lipoprotein particles, which consist of chylomicron remnants and very low density lipoprotein remnants, on vascular smooth muscle cell proliferation. Blood was collected from six patients with postprandial lipidemia two hours after their usual meal. Remnant lipoprotein particles were isolated from plasma by immuno-affinity chromatography containing two monoclonal antibodies, anti-apo A-I (H-12) and anti-apo B-100 (JI-H). Remnant lipoprotein particles, as well as betaVLDL, significantly stimulated the proliferation of porcine coronary artery smooth muscle cells in a concentration-dependent manner, whereas very low density lipoprotein (d < 1.006) was virtually ineffective. These observations are consistent with recent reports that triglyceride-rich lipoprotein remnants, which are rich in apo E as well, are atherogenic.