Standardization of Apolipoprotein Immunoassays by an Isotope Dilution Method

  • Philip Weech
  • Walter J. McConathy
  • Petar Alaupovic
  • James Fesmire
Conference paper

Abstract

Plasma lipoproteins consist of a mixture of lipid-protein particles differing in hydrated density, size and chemical composition (Nichols, 1967). The recognized existence of at least nine well-characterized apolipoproteins and their distribution throughout the entire density spectrum are further indications of the complex nature of this macromolecular system (Osborne and Brewer, 1977; Olofsson et al. 1978). As distinct constituents, the apolipoproteins represent suitable markers for the identification and differentiation of lipoprotein particles. To assess the physiological role of apolipoproteins in lipid transport processes and to evaluate the potential use of apolipoprotein profiles in clinical practice, various immunochemical procedures have been developed for the quantitative determination of almost all known plasma apolipoproteins (Alaupovic et al. 1978; Albers 1978). Although all three immunoassays, i.e., radioimmunoassay, radial immunodiffusion and electroimmunoassay, display a high degree of specificity, sensitivity and precision, the standardization of individual assays and the assessment of accuracy remain unsolved problems. To establish a standard for accuracy, we have applied a simple isotope dilution method to determine the A-II content in HDL3. This method also furnishes a standard for electroimmunoassay, not as a delipidized polypeptide but as a lipoprotein.

Keywords

Hydrated Urea Polyethylene Glycol Electrophoresis 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Alaupovic P, Curry MD, McConathy WJ (1978) Quantitative determination of human plasma apolipoproteins by electroimmunoassays. In: Carlson LA, Paoletti R, Sirtori CR, Weber G (eds) International Conference on Atherosclerosis. Raven Press, New York, pp 109–115Google Scholar
  2. Albers JJ (1978) An introduction to lipoprotein immunoassays. Test of the Month 4, No. 2Google Scholar
  3. Curry MD, Alaupovic P, Suenram CA (1976) Determination of apolipoprotein A and its constitutive A-I and A-II polypeptides by separate electroimmunoassays. Clin Chem 22: 315–322PubMedGoogle Scholar
  4. Horrocks DL (1975) Standardizing 125I source and determining 12I counting efficiencies of well-type gamma counting systems. Clin Chem 21: 370–375PubMedGoogle Scholar
  5. Nichols AV (1967) Human serum lipoproteins and their relationships. In: Lawrence TH, Gofman JW (eds) Advances in biological and medical physics. Vol 11, Academic Press, New York, pp 109–158Google Scholar
  6. Olofsson SO, McConathy WJ, Alaupovi P (1978) Isolation and partial characterization of a new acidic apolipoprotein (apolipoprotein F) from high density lipoproteins of human plasma. Biochemistry 17: 1032–1036PubMedCrossRefGoogle Scholar
  7. Osborne JC, Brewer HB, Jr (1977) The plasma lipoproteins. Adv. Protein Chem. 31: 253–337PubMedCrossRefGoogle Scholar
  8. Weech PK, McTaggart F, Mills GL (1978) Comparison of guinea-pig serum lipoproteins after iodination by two different methods. Biochem J 169: 687–695PubMedGoogle Scholar

Copyright information

© Springer-Verlag New York Inc. 1980

Authors and Affiliations

  • Philip Weech
  • Walter J. McConathy
  • Petar Alaupovic
  • James Fesmire

There are no affiliations available

Personalised recommendations