title: An enzyme-linked immunosorbent assay method to measure human apolipoprotein E levels using commercially available reagents: effect of apolipoprotein E polymorphism on serum apolipoprotein E concentration.
abstract: A sensitive and specific enzyme-linked immunosorbent assay (ELISA) for human apolipoprotein E (apo E) quantification using commercially available reagents is described. The assay is a noncompetitive, sandwich ELISA in which the wells were coated with a monoclonal EO1 antibody anti-human apo E and detected with a polyclonal antibody-peroxidase conjugate anti-apo E. The mean apo E concentration in 168 middle-aged subjects randomly selected from general population was 51.7 +/- 12.4 mg/liter. Apo E levels were highly correlated with apo E phenotypes. Apo E polymorphism, which shows a modulating effect in the catabolism of apo E containing lipoproteins, may explain a large fraction, 18.5%, of the variability of serum apo E levels in middle-aged population. Isoforms apo E2 and apo E4 have an opposite effect on the regulation of serum apo E concentrations. Individuals that express apo E2 isoform present higher apo E levels (65.5 mg/liter for apo E2/E3), whereas the average of individuals with apo E4 is lower (42.8 mg/liter for apo E4/E3) than general population.
authors.affiliation: Unit of Experimental Research, Ciutat Sanitària i Universitària de Bellvitge, Barcelona, Spain.
authors.forename: V
authors.initials: V
authors.lastname: Gracia
authors.forename: C
authors.initials: C
authors.lastname: Fiol
authors.forename: I
authors.initials: I
authors.lastname: Hurtado
authors.forename: X
authors.initials: X
authors.lastname: Pintó
authors.forename: J M
authors.initials: JM
authors.lastname: Argimon
authors.forename: M J
authors.initials: MJ
authors.lastname: Castiñeiras
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D053329:Apolipoprotein E2; D053318:Apolipoprotein E3; D053327:Apolipoprotein E4; D001057:Apolipoproteins E / Q000097:blood* / Q000235:genetics*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods* / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D007202:Indicators and Reagents; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011110:Polymorphism, Genetic; D012016:Reference Values; D012680:Sensitivity and Specificity
chemical_list: D053329:Apolipoprotein E2; D053318:Apolipoprotein E3; D053327:Apolipoprotein E4; D001057:Apolipoproteins E; D007202:Indicators and Reagents; D008055:Lipids