Lipoproteins and Atherosclerosis Christopher K. Glass*†‡ and Joseph L. Witztum* Specialized Center of Research on Molecular Serum cholesterol is carried by several lipoprotein parti-Medicine and Atherosclerosis cles that perform the complex physiologic tasks of* Department of Medicine transporting dietary and endogenously produced lipids Division of Endocrinology and Metabolism(reviewed in Witztum and Steinberg, 1995). Chylomicrons† Department of Cellular and Molecular Medicine provide the primary means of transport of dietary lipids, University of California, San Diego while very low density lipoproteins (VLDL), low density 9500 Gilman Drive lipoproteins (LDL), and high density lipoproteins (HDL) La Jolla, California 92093 function to transport endogenous lipids. Triglyceriderich VLDL particles containing apolipoprotein B-100 (apo B-100) and apolipoprotein E (apo E) are synthesized by the liver and function to transport fatty acids to adi-