Horseradish‐peroxidase‐conjugated anti‐erythropoietin antibodies for direct recombinant human erythropoietin detection: Proof of concept. Issue 3 (25th November 2020)

• Record Type: Journal Article
• Authors: Voss, Sven C.; Orie, Nelson N.; El‐Saftawy, Wesal; Saghbazarian, Stephanie; Al‐Kaabi, Alanoud; Georgakopoulos, Costas; Athanasiadou, Ioanna; Mohamed‐Ali, Vidya; Al‐Maadheed, Mohammed
• Is Part Of: Drug testing and analysis. Volume 13:Issue 3(2021)
• Page Start: 529
• Page End: 538
• Publication Date: 2020-11-25
• Subjects: antibody -- direct western blot -- doping -- electrophoresis -- EPO; Drugs -- Analysis -- Periodicals; Drug testing -- Periodicals; Chemistry, Forensic -- Periodicals; 615.1901
• DOI: 10.1002/dta.2957
• Languages: English
• ISSNs: 1942-7603

Abstract

Abstract: Antidoping testing for recombinant human erythropoietin (EPO) is routinely performed by gel electrophoresis followed by western blot analysis with primary and secondary antibodies. The two antibody steps add more than 24 h to the testing time of a purified sample. The aim of this study was to test the concept of using directly horseradish‐peroxidase (HRP)‐conjugated anti‐EPO primary antibody, without the need for a secondary antibody, to reduce the analysis time and eliminate non‐specific cross‐reactivity with secondary antibodies. An in‐house, periodate coupling (R&D systems, clone AE7A5) and three commercially available anti‐human EPO‐HRP conjugates from Genetex, Novus Biologicals and Santa Cruz were evaluated for specificity and sensitivity, using recombinant human EPO standards, negative human urine samples and urine samples from an EPO excretion study. The in‐house anti‐EPO‐HRP conjugate was performed as well as the current two‐step application of unconjugated primary and secondary antibodies used in routine analysis, with comparable specificity and sensitivity. The analysis time was markedly reduced for purified samples from 25 h with the routine method down to 7 h with the in‐house HRP conjugate. Of the three commercially available conjugates tested, only the Santa Cruz anti‐EPO‐HRP conjugate showed comparable specificity but had lower sensitivity to both the in‐house and the antibody combination currently applied routinely. The other two commercially available conjugates (Genetex and Novus Biologicals) did not show any visible bands with the EPO standards. The results clearly demonstrate the potential utility of a directly HRP‐conjugated anti‐EPO antibody to reduce analysis time for EPO in doping control. Abstract : Detection of EPO is usually performed by western blot with primary and secondary antibodies. The method evaluated here tested successfully the concept of using a directly horseradish‐peroxidase (HRP)‐conjugated anti‐EPO primary antibody and reduced the EPO primary antibody and the necessary analysis time from 25 to 7 h.