We describe a double-antibody radioimmunoassay for apolipoprotein B with use of monoclonal antibodies. Values for 32 patients with various lipid disorders, obtained with use of one of the monoclonal antibodies (464B1B6), were similar to those obtained with use of a polyclonal antiserum. When we used another monoclonal antibody (465C3D1) the values were significantly lower. Monoclonal antibody 4...

Lipoprotein(a) [Lp(a)] plays an important role in atherosclerosis. The biological effects of Lp(a) have been attributed either to apolipoprotein(a) or to its low-density lipoprotein-like particle. Lp(a) contains platelet-activating factor acetylhydrolase, an enzyme that exhibits a Ca2+-independent phospholipase A2 activity and is complexed to lipoproteins in plasma; thus, it is also referred to...

We investigated age- and sex-related differences in the structure and composition of two species of lipoproteins that contain apoprotein (apo) A-I (A-I Lp): lipoproteins containing apo A-I and apo A-II (Lp A-I/A-II), and lipoprotein containing apo A-I but no apo A-II (Lp A-I), which were isolated by immunoaffinity chromatography. Sixty normolipidemic volunteers were assigned to one of three gro...

The aim of the present study was to investigate the associations between total adiposity, body fat distribution, and plasma lipoprotein levels within groups of women defined on the basis of apolipoprotein E phenotypes, in order to verify whether apoE polymorphism could modify these associations. In women having only apolipoprotein E3 isoforms (n = 24), body fat mass, the waist: hip circumferenc...

We describe a disorder in which low-density lipoprotein (LDL)-cholesterol and apolipoprotein B are in low concentration (0.47 mmol/L and 0.28 g/L, respectively) and chylomicrons are still present in plasma after an 18-h fast. The d less than 1.006 fraction was isolated by flotation ultracentrifugation and the apolipoproteins were analyzed by electrophoresis, immunoblotting with anti-apolipoprot...

Plasma glutathione peroxidase (GSHPx) has been suggested to reduce submicromolar levels of free fatty acid hydroperoxides and phosphatidylcholine hydroperoxides (PC-OOH), and therefore these hydroperoxides are undetectable in human blood plasma. The capacity for the reduction should be about 2.5 microM as the level of glutathione in human plasma is about 5 microM. However, 2 h of aerobic incuba...

Lipoprotein(a) is an atherogenic lipoprotein whose function and plasma concentration reflect the structure and regulation of the apolipoprotein(a) gene. Apolipoprotein(a) is a close homologue of plasminogen, and their genes are tightly linked on chromosome 6. To further characterize these genes, we analyzed overlapping human genomic yeast artificial chromosome clones, which revealed a cluster o...

Apolipoprotein A-IV is found in mesenteric lymph chylomicrons, very low density lipoprotein particles, high density lipoprotein particles, and in the lipoprotein-free fraction of plasma. Apolipoprotein A-IV is polymorphic in a variety of species including human, dog, and horse. Efforts to estimate the impact of apolipoprotein A-IV structural variation on quantitative lipid levels in humans have...