WE HAVE previously presented evidence relating certain lipoprotein molecules of the serum of human beings and experimental animals with the development of atherosclerosis.1 It is the purpose of this report to evaluate a clinical follow-up study which has further amplified this relationship.
The basic premise of this research was that there might be a defect in the molecules which transport fats and cholesterol that could be more intimately related to the pathogenesis of atherosclerosis than are the total analytical levels of the various lipids themselves, e. g., serum cholesterol levels. Since cholesterol, its esters, neutral fat, and phospholipids are all transported in the blood via giant lipoprotein molecules, it was necessary to develop a technique for measuring both the types and the concentration of lipoproteins present in a small sample of blood from an individual patient. The ultracentrifuge has proved highly useful for this purpose. In the ultracentrifuge, under