Lipoprotein preparation, human

Fig. 4 a. Precipitation lines formed by Ouchterlony agar diffusion technic with serum from normal subject (1), patients with Tangier disease (2, 3) and patient with a-jS-lipoproteinemia (4) against rabhit antibodies prepared against human lipoproteins of density 1.063—1.21 ( anti-HDL ). Both precipitation lines at (1) are attributed to HDL... 

Fig. 4 b. Arrangement same as in fig. 4 a, except rabbit antibodies were prepared against human lipoproteins of density <1.063 ( anti-LDL ). Here both patients with Tangier disease demonstrated LDL, which was further shown by immunoelectrophoresis. Plates prepared by Dr. R. I. Levy. Source Hoffman and Fredrickson (1965). (Reproduced with kind permission of The American Journal of... 

The incorporation of A-acetylneuraminic acid from the CMP-nucleotide derivative into neuraminidase-treated human lipoproteins of very low density was catalysed by preparations from porcine liver microsomes. The activity of the CMP-A -acetylneuraminic acidiglycoprotein sialyltransferase present in rat-liver microsomes has been shown to be stimulated by UDP, but to be inhibited by CMP. The functions of glycosyltransferases in the processes of recognition and binding of asialoglycoproteins in liver have been investigated. ... 

In many sera there exists either a host of lipoprotein species which give rise to closely spaced boundaries or an actual continuum of lipoproteins with respect to flotation rate. This complicates the problem of the determination of the concentration of individual lipoprotein species. Figure 6 is a reproduction of the analytical ultracentrifuge film record of a human lipoprotein concentrate (Preparative Type 1), showing a broad deflection... 

Oncley, J.L., Gurd, F.R.N. and Melin, M. (1950). Preparation and properties of serum and plasma proteins XXV. Composition and properties on human serum d-lipoprotein. J. Am. Chem. Soc. 72, 458-464. 

Human plasma lipoproteins and lipoprotein deficient plasma (LPDS) were prepared from normal plasma of healthy individuals by differential ultracentrifugation on KBr gradients (16). 

Chocolate has antioxidant properties for low-density lipoproteins and hence could prevent heart disease. Foods and beverages derived from cocoa beans have been consumed by humans since 460 a.d. Cocoa pods from the cocoa tree (Theobroma cacao) are harvested and the beans removed and fermented. Dried and roasted beans contain about 300 chemicals including caffeine, theobromine, and phenethylamine. Chocolate liquor is prepared by finely grinding the nib of the cocoa bean and is the basis for all chocolate products. Cocoa powder is made by removing part of the cocoabutter from the liquor. Bittersweet chocolate, sometimes called dark chocolate, contains between 15 and 60% chocolate liquor, the remainder being cocoa butter, sugar, and other additives. Milk chocolate is the predominant form of chocolate consumed in the U.S. and typically contains 10 to 12% chocolate liquor. 

Phenolic compounds also have important antioxidant properties, protecting food from oxidation [9]. The antioxidant properties of phenolic compounds can have an impact on human health and they are regarded as having a protective effect against low-density lipoprotein (LDL) oxidation and cardiovascular diseases [3], Recently phenolic compounds have been widely used in cosmetic preparations to delay aging [10]. 

It is likely that the major site of uptake of apoE-containing remnants of the triglyceride-rich lipoproteins is the liver. As apoC is removed and the apoE apoC ratio rises, so the remnant lipoprotein becomes more amenable to hepatic uptake by specific receptors (S25, S28, W16, W17). VLDL remnants and IDL also experience apoE-mediated binding by apoB,E receptors in hepatic cell membrane preparations (H35, Mil). The smallest apoE-rich VLDL subfractions from normolipidemic human plasma compete with LDL for fibroblast (apoB-100,E) receptors in vitro (T10) and in cultured fibroblasts (F17, G2, 17). ... 

A 9-methoxyellipticine (2)-low density lipoprotein (LDL) complex was formulated by Soula and co-workers (742) and found to be 10 times more active than 2 against L1210 and P388 leukemia in vitro. This activity seems to depend on the LDL high-affinity receptor since LDL reduces the antitumor activity. The complex was prepared by adding 2 to a dimyristoyl phosphatidylcholine, cho-lesteryl oleate-stabilized microemulsion and then fusing with human LDL. 

An alternative to the formulation of the unsubstituted ZnPc is through its non-covalent binding to bovine serum albumin (BSA). BSA-delivered ZnPc readily redistributes from BSA to high density lipoproteins after intravenous administration, as has been shown for liposomal preparations of ZnPc [56]. Tumor control was obtained at 0.5 jumol kg both in EMT-6 tumor-bearing Balb/c mice and in T 380 human colon carcinoma in nude mice [69]. 

ZnPc has also been complexed with human low-density lipoprotein (LDL). This results in higher tumor uptake and tumor-muscle ratio as compared with the DPPC liposome preparation [56,70]. 

Schmid, K. 1953, Preparation and properties of serum and plasma proteins. XXIX. Separation from human plasma of polysaccharides, peptides and proteins of low molecular weight. Crystallization of an acid lipoprotein. Journal of The American. Chemical. Society 75, 60-68. 

Three specific human monoclonal IgG autoantibodies that recognize oxidized MDA-LDL have been prepared using phage libraries (S6). Such a panel of antibodies may be of value in defining the composition of arteriosclerotic plaques in various stages of development (G2). They may also be directed at cells, lipoproteins, and matrix molecules in a way that can help identify the source of OxLDL in humans. Such human antibodies may also be used in assays. There is still a good deal of research needed to sort out these questions. 

Attempts have been made in the author s laboratory to obtain a lipid-free water-soluble product from the d < 1.019 and d 1.019-1.063 low-density human serum lipoproteins by using the ethanol-ether procedure successfully applied to the high-density class (Scanu et al., 1958a). The precipitate obtained proved insoluble in the various buffered media alone or in the presence of 1-4 M urea. Banaszak and McDonald (1962) attempted separation of the protein moiety of d 1.019-1.063 serum lipoproteins by a pentane extraction of a lyophilized preparation. The product obtained, insoluble in common buffer solutions, was solubilized in carbonate buffer of pH 10.2 in the presence of 4 M urea, leading to prompt formation of a gel, which persisted after removal of urea by dialysis. 

For separation and quantitation of human serum lipoproteins, several technics are currently used. These technics include preparative ultracentrifugation (1-3), gel filtration (1,4), selective precipitation with polyanion/divalent cation reagents (1,5), electrophoresis (1,6), affinity choromatography (7), and ultrafiltration (8). For effective separation of all major lipoprotein classes, a combination procedure consisting of several technics above mentioned is frequently used. Therefore, this leads to difficulties, that is, the loss and alteration or decomposition of lipoprotein components due to time consuming experimental procedures. ... 

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