Int J Sports Med 2009; 30(2): 80-86
DOI: 10.1055/s-0028-1103283
Physiology & Biochemistry

© Georg Thieme Verlag KG Stuttgart · New York

Identification of Darbepoetin Alfa in Human Plasma by Liquid Chromatography Coupled to Mass Spectrometry for Doping Control

F. Guan 1 , C. E. Uboh 2 , L. R. Soma 1 , E. Birksz 1 , J. Chen 1
  • 1School of Veterinary Medicine, University of Pennsylvania, Kennett Square, Pennsylvania, United States
  • 2PA Equine Toxicology and Research Center, Department of Chemistry, West Chester University, West Chester, Pennsylvania, United States
Further Information

Publication History

accepted after revision July 1, 2008

Publication Date:
28 January 2009 (online)

Abstract

Darbepoetin alfa (DPO) or Novel Erythropoiesis Erythropoiesis Stimulating Protein (NESP), an analog of recombinant human erythropoietin (rhEPO), is abused as a blood doping agent along with the latter in human sports. This paper describes a new method for unequivocal identification of DPO in human plasma. The analyte was extracted from plasma by immunoaffinity separation with anti-rhEPO antibodies, digested by trypsin followed by PNGase F, and analyzed by liquid chromatography coupled to tandem mass spectrometry. The deglycosylated tryptic peptide, T9, was employed in DPO identification using liquid chromatographic retention time and major product ions of the T9 peptide. The limit of detection of this method for DPO was 0.1 ng/mL in plasma, and that of identification was 0.2 ng/mL. This method is definitive and devoid of false positive results, providing “mass fingerprints” for identification of DPO in human plasma samples. Although this method is not applicable to identification of rhEPO in human plasma because it cannot differentiate rhEPO from endogenous EPO, it is the first successful attempt towards establishing a reliable and selective method for definitive identification of exogenously administered EPOs in doping control analyses.

References

  • 1 Bajla I, Hollander I, Gmeiner G, Reichel C. Quantitative analysis of images in erythropoietin doping control.  Med Biol Eng Comput. 2005;  43 403-409
  • 2 Belalcazar V, Gallego RG, Llop E, Segura J, Pascual JA. Assessing the instability of the isoelectric focusing patterns of erythropoietin in urine.  Electrophoresis. 2006;  27 4387-4395
  • 3 Beullens M, Delanghe JR, Bollen M. False-positive detection of rhEpo remains a real concern. Reply to comments.  Blood. 2006;  108 1779-1780
  • 4 Beullens M, Delanghe JR, Bollen M. False-positive detection of recombinant human erythropoietin in urine following strenuous physical exercise.  Blood. 2006;  107 4711-4713
  • 5 Cindric M, Bindila L, Cepo T, Peter-Katalinic J. Mass spectrometry-based glycoproteomic approach involving lysine derivatization for structural characterization of recombinant human erythropoietin.  J Proteome Res. 2006;  5 3066-3076
  • 6 Egrie JC, Browne JK. Development and characterization of novel erythropoiesis stimulating protein (NESP).  Br J Cancer. 2001;  84 3-10
  • 7 Guan F, Uboh C, Soma L, Birks E, Chen JW, Mitchell J, You YW, Rudy J, Xu F, Li XQ, Mbuy G. LC-MS/MS method for confirmation of recombinant human erythropoietin and darbepoetin alpha in equine plasma.  Anal Chem. 2007;  79 4627-4635
  • 8 Khan A, Baker MS. Non-specific binding of monoclonal human erythropoietin antibody AE7A5 to Excherichia coli and Saccharomyces cerevisiae proteins.  Clin Chim Acta. 2007;  379 173-175
  • 9 Khan A, Grinyer J, Truong ST, Breen EJ, Packer NH. New urinary EPO drug testing method using two-dimensional gel electrophoresis.  Clin Chim Acta. 2005;  358 119-130
  • 10 Khoshnoodi J, Hill S, Tryggvason K, Hudson B, Friedman DB. Identification of N-linked glycosylation sites in human nephrin using mass spectrometry.  J Mass Spectrom. 2007;  42 370-379
  • 11 Krantz SB. Erythropoietin.  Blood. 1991;  77 419-434
  • 12 Lamon S, Robinson N, Mangin P, Saugy M. Detection window of Darbepoetin-a following one single subcutaneous injection.  Clin Chim Acta. 2007;  379 145-149
  • 13 Lasne F. Double-blotting: a solution to the problem of nonspecific binding of secondary antibodies in immunoblotting procedures.  J Immunol Methods. 2003;  276 223-226
  • 14 Lasne F, Martin L, Crepin N, Ceaurriz J de. Detection of isoelectric profiles of erythropoietin in urine: differentiation of natural and administered recombinant hormones.  Anal Biochem. 2002;  311 119-126
  • 15 Lasne F, Ceaurriz J de. Recombinant erythropoietin in urine.  Nature. 2000;  405 635
  • 16 Leigh-Smith S. Blood boosting.  Br J Sports Med. 2004;  38 99-101
  • 17 Lippi G, Guidi G. Laboratory screening for erythropoietin abuse in sport: an emerging challenge.  Clin Chem Lab Med. 2000;  38 13-19
  • 18 Ma DD, Wei AQ, Dowton LA, Lau KS, Wu ZH, Ueda M. Assessment of an EIA for measuring human serum erythropoietin as compared with RIA and an in-vitro bioassay.  Br J Haematol. 1992;  80 431-436
  • 19 Mann M, Wilm M. Error-tolerant identification of peptides in sequence databases by peptide sequence tags.  Anal Chem. 1994;  66 4390-4399
  • 20 Pascual JA, Belalcazar V, Bolos C de, Gutierrez R, Llop E, Segura J. Recombinant erythropoietin and analogues: a challenge for doping control.  Ther Drug Monit. 2004;  26 175-179
  • 21 Stanley SM, Poljak A. Matrix-assisted laser-desorption time-of flight ionisation and high-performance liquid chromatography-electrospray ionisation mass spectral analyses of two glycosylated recombinant epoetins.  J Chromatogr B Analyt Technol Biomed Life Sci. 2003;  785 205-218
  • 22 Stubiger G, Marchetti M, Nagano M, Reichel C, Gmeiner G, Allmaier G. Characterisation of intact recombinant human erythropoietins applied in doping by means of planar gel electrophoretic techniques and matrix-assisted laser desorption/ionisation linear time-of-flight mass spectrometry.  Rapid Commun Mass Spectrom. 2005;  19 728-742
  • 23 Stubiger G, Marchetti M, Nagano M, Grimm R, Gmeiner G, Reichel C, Allmaier G. Characterization of N- and O-glycopeptides of recombinant human erythropoietins as potential biomarkers for doping analysis by means of microscale sample purification combined with MALDI-TOF and quadrupole IT/RTOF mass spectrometry.  J Sep Sci. 2005;  28 1764-1778
  • 24 Thevis M, Schaenzer W. Mass spectrometry in sports drug testing: structure characterization and analytical assays.  Mass Spectrom Rev. 2007;  26 79-107
  • 25 Thevis M, Schaenzer W. Identification and characterization of peptides and proteins in doping control analysis.  Curr Proteomics. 2005;  2 191-208
  • 26 Winearls CG. Recombinant human erythropoietin: 10 years of clinical experience.  Nephrol Dial Transplant. 1998;  13 ((Suppl. 2)) 3-8
  • 27 Wognum AW, Lam V, Goudsmit R, Krystal G. A specific in vitro bioassay for measuring erythropoietin levels in human serum and plasma.  Blood. 1990;  76 1323-1329
  • 28 Zhou GH, Luo GA, Zhou Y, Zhou KY, Zhang XD, Huang LQ. Application of capillary electrophoresis, liquid chromatography, electrospray-mass spectrometry and matrix-assisted laser desorption/ionization – time of flight – mass spectrometry to the characterization of recombinant human erythropoietin.  Electrophoresis. 1998;  19 2348-2355

Correspondence

Dr. F. GuanPhD 

School of Veterinary Medicine

University of Pennsylvania

220 East Rosedale Avenue

West Chester, PA 19382

United States

Phone: +610\436\35 01

Fax: +610\436\35 04

Email: guanf@vet.upenn.edu

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