Lipids and lipoproteins of serum and organ tissues in a case of familial hyperlipoproteinemia type II.

Lipids and lipoproteins of serum and various organ tissues of a patient with familial hyperlipoproteinemia homozygous Type II were studied. It was found that low density lipoprotein between densities of 1.006 and 1.063 was a major component of serum of the patient. The isolated low density lipoprotein appeared to be rather similar to that of normal human serum from the viewpoints of chemical composition and physico-chemical properties. Antibody against the low density lipoprotein of the patient reacted not only with the same lipoprotein, but also with normal human low density lipoproteins. Immunoelectrophoresis of the antibody gave a single precipitin line against only the low density lipoprotein. Immunofluorescent techniques using the fluorescein labeled antibody showed localization of low density lipoprotein in cytoplasm of hepatocytes of both the patient and other human. No fluorescences were found in other organ cells except in their capillary tubes and renal glomerulus in the hyperlipoproteinemia Type II. It was noted that tuberous xanthomata contained fairly large amounts of cholesterol and cholesterol ester. Fatty acid composition of neutral lipids and phospholipids from the serum low density lipoprotein, xanthomata, liver and other organ tissues were compared with each other. Chomesterol ester of the xanthomata contained much smaller amounts of polyunsaturated fatty acids as compared with those of the low density lipoprotein and other tissue. Also, composition of free fatty acids in liver differed from those of other tissues.