title: Isoelectric focusing of apolipoproteins in immobilized pH gradients: improved determination of apolipoprotein E phenotypes.
abstract: A method for isoelectric focusing of apolipoprotein E in an immobilized pH gradient with added carrier ampholytes has been developed. This method is an improvement over conventional isoelectric focusing of apolipoprotein E with respect to resolution, reproducibility, and simplicity. Since monosialo isoforms are resolved from the normally cofocusing asialo isoforms, unique patterns are obtained for all 6 common apolipoprotein E phenotypes. The method can also be applied to the screening of apolipoprotein A and C isoforms. Delipidated very low density lipoproteins (VLDL) have been used as the source of apolipoprotein E and C. Apolipoprotein A isoforms were focused directly from detergent-treated serum. Immunodetection of apolipoprotein E using capillary transfer was found to be compatible with the described method.
authors.affiliation: Medizinische Universitätsklinik, Abteilung Sport- und Leistungsmedizin, Freiburg, Federal Republic of Germany.
authors.forename: M W
authors.initials: MW
authors.lastname: Baumstark
authors.forename: A
authors.initials: A
authors.lastname: Berg
authors.forename: M
authors.initials: M
authors.lastname: Halle
authors.forename: J
authors.initials: J
authors.lastname: Keul
mesh_terms: D001053:Apolipoproteins / Q000097:blood* / Q000302:isolation & purification; D001057:Apolipoproteins E / Q000097:blood* / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D006863:Hydrogen-Ion Concentration; D015151:Immunoblotting / Q000379:methods; D007525:Isoelectric Focusing / Q000379:methods; D010641:Phenotype
chemical_list: D001053:Apolipoproteins; D001057:Apolipoproteins E