title: Inability of Some Commercial Assays to Measure Suppression of Glucagon Secretion.
abstract: Glucagon levels are increasingly being included as endpoints in clinical study design and more than 400 current diabetes-related clinical trials have glucagon as an outcome measure. The reliability of immune-based technologies used to measure endogenous glucagon concentrations is, therefore, important. We studied the ability of immunoassays based on four different technologies to detect changes in levels of glucagon under conditions where glucagon levels are strongly suppressed. To our surprise, the most advanced technological methods, employing electrochemiluminescence or homogeneous time resolved fluorescence (HTRF) detection, were not capable of detecting the suppression induced by a glucose clamp (6 mmol/L) with or without atropine in five healthy male participants, whereas a radioimmunoassay and a spectrophotometry-based ELISA were. In summary, measurement of glucagon is challenging even when state-of-the-art immune-based technologies are used. Clinical researchers using glucagon as outcome measures may need to reconsider the validity of their chosen glucagon assay. The current study demonstrates that the most advanced approach is not necessarily the best when measuring a low-abundant peptide such as glucagon in humans.
authors.affiliation: Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark.
authors.forename: Nicolai J
authors.initials: NJ
authors.lastname: Wewer Albrechtsen
authors.affiliation: Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark.
authors.forename: Simon
authors.initials: S
authors.lastname: Veedfald
authors.affiliation: Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark.
authors.forename: Astrid
authors.initials: A
authors.lastname: Plamboeck
authors.affiliation: Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark.
authors.forename: Carolyn F
authors.initials: CF
authors.lastname: Deacon
authors.affiliation: Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark.
authors.forename: Bolette
authors.initials: B
authors.lastname: Hartmann
authors.affiliation: Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; Center for Diabetes Research, Gentofte Hospital, University of Copenhagen, 2900 Hellerup, Denmark.
authors.forename: Filip K
authors.initials: FK
authors.lastname: Knop
authors.affiliation: Center for Diabetes Research, Gentofte Hospital, University of Copenhagen, 2900 Hellerup, Denmark.
authors.forename: Tina
authors.initials: T
authors.lastname: Vilsboll
authors.affiliation: Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark.
authors.forename: Jens J
authors.initials: JJ
authors.lastname: Holst
mesh_terms: D000328:Adult; D001285:Atropine / Q000737:chemistry; D004563:Electrochemistry / Q000379:methods; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005453:Fluorescence; D005934:Glucagon / Q000032:analysis* / Q000097:blood / Q000378:metabolism*; D015309:Glucose Clamp Technique; D064368:Healthy Volunteers; D006403:Hematologic Tests / Q000379:methods*; D006801:Humans; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D049449:Luminescence; D008297:Male; D011863:Radioimmunoassay / Q000379:methods; D015203:Reproducibility of Results
chemical_list: D007328:Insulin; D001285:Atropine; D005934:Glucagon
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