title: Establishment of the first WHO Erythropoietin antibody reference panel: Report of an international collaborative study.
abstract: A panel of 9 fully human monoclonal antibodies against human erythropoietin (EPO) with defined characteristics (non-neutralizing, neutralizing, various isotypes, affinities) representative of those evident in antibody-mediated pure red cell aplasia (PRCA) and non-PRCA patients were formulated and lyophilized. The panel was evaluated in a multi-centre international collaborative study comprising eighteen different laboratories using different assay platforms including those in routine use. These included binding assays, some based on use of novel technologies and neutralization assays predominantly employing EPO responsive cell-lines. Results showed that detection and titre varied depending on antibody characteristics and the method used. Only selective assay platforms were capable of detecting the diverse repertoire of EPO antibodies in the panel indicating that some clinically relevant antibodies are likely to be missed in some assays. Importantly, the clinical samples from PRCA patients were distinguished as antibody-positive and the healthy donor serum as antibody negative across all different platforms tested. For neutralization, data was generally consistent across the assays for the different samples regardless of the cell-line and the assay conditions. The heterogeneity in data from the study clearly indicated the need for reference standards for consistency in detecting and measuring EPO antibodies across different assay platforms for monitoring the safety and efficacy of erythropoiesis stimulating agents. Therefore, the WHO ECBS at its meeting in October'15 established the EPO antibody panel, available from NIBSC, to facilitate decision-making on assay selection for testing antibodies against human EPO, for evaluating assay performance of antibody assays for clinical use, for assay validation and for standardization.
authors.affiliation: Biotherapeutics Group, NIBSC, Blanche Lane, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK. Electronic address: Meenu.Wadhwa@nibsc.org.
authors.forename: Meenu
authors.initials: M
authors.lastname: Wadhwa
authors.affiliation: Medical Sciences Clinical Immunology, Amgen, Inc., 1 Amgen Center Drive, Thousand Oaks, CA, USA.
authors.forename: Daniel T
authors.initials: DT
authors.lastname: Mytych
authors.affiliation: Biotherapeutics Group, NIBSC, Blanche Lane, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK.
authors.forename: Chris
authors.initials: C
authors.lastname: Bird
authors.affiliation: Department of Pharmacokinetics and Drug Metabolism, Amgen, Inc., 1 Amgen Center Drive, Thousand Oaks, CA, USA.
authors.forename: Troy
authors.initials: T
authors.lastname: Barger
authors.affiliation: Technology Development and Infrastructure, NIBSC, Blanche Lane, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK.
authors.forename: Thomas
authors.initials: T
authors.lastname: Dougall
authors.affiliation: Department of Pharmacokinetics and Drug Metabolism, Amgen, Inc., 1 Amgen Center Drive, Thousand Oaks, CA, USA.
authors.forename: Hong
authors.initials: H
authors.lastname: Han
authors.affiliation: Technology Development and Infrastructure, NIBSC, Blanche Lane, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Rigsby
authors.affiliation: IPM Biotech, Lademannbogen 61, 22339, Hamburg, Germany.
authors.forename: Arno
authors.initials: A
authors.lastname: Kromminga
authors.affiliation: Biotherapeutics Group, NIBSC, Blanche Lane, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK.
authors.forename: Robin
authors.initials: R
authors.lastname: Thorpe
mesh_terms: D000906:Antibodies / Q000097:blood* / Q000276:immunology*; D000911:Antibodies, Monoclonal / Q000276:immunology; D000915:Antibody Affinity; D004921:Erythropoietin / Q000276:immunology*; D006801:Humans; D007118:Immunoassay / Q000379:methods / Q000592:standards*; D012010:Red-Cell Aplasia, Pure / Q000276:immunology; D012015:Reference Standards; D014944:World Health Organization
chemical_list: D000906:Antibodies; D000911:Antibodies, Monoclonal; C554270:EPO protein, human; D004921:Erythropoietin
keywords: Antibody assays; Antibody reference reagents; Assay performance; Immunogenicity; Selection; Validation