title: Determination of apolipoprotein B-48 in plasma by a competitive ELISA.
abstract: BACKGROUND
  Apolipoprotein B-48 (apoB-48) is produced by the small intestine, as part of chylomicrons, and appears to be a suitable marker for clinical studies of postprandial lipoproteins and related cardiovascular risk. Our aim was to develop, for routine analysis, an assay to quantify apoB-48 in plasma samples.
  
  
  METHODS
  A microtiter plate was coated with a C-terminal apoB-48-specific heptapeptide. Plasma samples were incubated with appropriate detergent to allow competition between immobilized antigen and plasma apoB-48. Appropriate calibration curves were obtained in the ELISA, using calibrated lymph and chylomicrons.
  
  
  RESULTS
  Treatment of plasma samples with the mild detergent Triton X-100 allowed an efficient competition between immobilized antigen and plasma apoB-48. No cross-reactivity was found with apoB-100, as checked by ELISA and Western blot analysis. Intra- and interassay CVs were 5.4% and 5. 5%, respectively. In healthy subjects, apoB-48 concentrations markedly increased in the postprandial state, in parallel with triglycerides.
  
  
  CONCLUSIONS
  This new ELISA allows determination of the concentration of apoB-48 in normolipidemic plasma.
authors.affiliation: Laboratoire Central, Hôpital Sainte-Marguerite, 270 Bd Sainte-Marguerite BP 29, 13274 Marseille Cedex 09, France.
authors.forename: A M
authors.initials: AM
authors.lastname: Lorec
authors.forename: C
authors.initials: C
authors.lastname: Juhel
authors.forename: Y
authors.initials: Y
authors.lastname: Pafumi
authors.forename: H
authors.initials: H
authors.lastname: Portugal
authors.forename: A M
authors.initials: AM
authors.lastname: Pauli
authors.forename: D
authors.initials: D
authors.lastname: Lairon
authors.forename: C
authors.initials: C
authors.lastname: Defoort
mesh_terms: D053283:Apolipoprotein B-48; D001055:Apolipoproteins B / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D015153:Blotting, Western; D003429:Cross Reactions; D003902:Detergents; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D017830:Octoxynol; D019518:Postprandial Period; D012016:Reference Values; D012680:Sensitivity and Specificity
chemical_list: D053283:Apolipoprotein B-48; D001055:Apolipoproteins B; D015415:Biomarkers; D003902:Detergents; D017830:Octoxynol