Apolipoprotein monoclonal antibodies

B. Mapping of Apolipoprotein B on Low-Density Lipoprotein Surfaces with Monoclonal Antibodies... 

Location of Epitopes Recognized by Monoclonal Antibodies against Apolipoprotein ... 

Most apolipoprotein B (apoB) in rat hepatocyte membranes is membrane-bound. Various data based on glycosylation specific monoclonal antibodies and carbohydrate-specific labelling suggest that membrane-bound apoB is more glycosylated than plasma lipoprotein apoB [30]. 

While lipoproteins are the products of many different genes, the major apolipoproteins share properties distinguishing them from most lipid-free and membrane-associated proteins. For example, apolipoproteins consist of a single polypeptide chain that has relatively little tertiary structure. Most apolipoproteins contain stretches of amphipathic alpha-helix, whose hydrophobic face can be turned to the lipid surface of the particle. The apolipoproteins are flexible, as is reflected in their unusually small free energy of unfolding. As these apolipoproteins expand and contract at the cell surface, different protein domains are exposed that are detectable with monoclonal antibodies. These properties reflect the role of apolipoproteins at the surface of lipoprotein particles whose size changes as they circulate. 

Koren E, Alaupovic P, Lee DM, Dashti N, Kloer HU, Wen G (1987) Selective isolation of human plasma low-density lipoprotein particles containing apohpoproteins B and E by use of a monoclonal antibody to apolipoprotein B. Biochemistry 26 2734-2746... 

Mapping of hpoprotein particles was obtained mainly with monoclonal antibodies. Stable mouse or rat hybridoma ceU lines have been developed in our laboratory, in collaboration with others, to produce monoclonal antibodies against human apolipoproteins B, A-I, A-II, C-III, E, and (a). 

Monoclonal antibodies can be used as first antibody in our immunoenzymometric assay. As any single epitope of an apolipoprotein may be more or less exposed depending on which particle one is examining, monoclonal antibodies can separate lipoproteins that may be similar by physicochemical criteria. 

Tl. Taddei-Peters, W. C., Butman, B. T., Jones, G. R., Venetta, T. M., Macomber, P. F., and Ransom, J. H., Quantification of lipoprotein(a) particles containing various apolipoprotein(a) isoforms by a monoclonal anti apo(a) capture antibody and a polyclonal anti-apolipoprotein B detection antibody sandwich enzyme immunoassay. Clin. Chem. (Winston-Salem, NC) 39, 1382-1389 (1993). 

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