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

Postprandial lipidemia, characterized by high plasma triglyceride-rich lipo protein remnants, is associated with atherosclerosis. It has also been know n that proliferation of Vascular smooth muscle cells is crucial for the dev elopment of atherosclerosis. In this study, we investigated the direct effe ct of remnant]lipoprotein particles, which consist of chylomicron remnants and very low density lipoprotein remnants, on vascular smooth muscle cell p roliferation. Blood was collected from six patients with postprandial lipid emia two hours after their usual meal. Remnant lipoprotein particles were i solated from plasma by immune-affinity chromatography containing two monocl onal antibodies, anti-ape A-I (H-12) and anti-ape B-100 (JI-H). Remnant lip oprotein particles, as well as beta VLDL, significantly stimulated the prol iferation of porcine coronary artery smooth muscle cells in a concentration -dependent manner, whereas very low density lipoprotein (d < 1.006) was vir tually ineffective. These observations are consistent with recent reports t hat triglyceride-rich lipoprotein remnants, which are rich in apo E as well , are atherogenic.