title: Validation of a quantitative cerebrospinal fluid alpha-synuclein assay in a European-wide interlaboratory study.
abstract: Decreased levels of alpha-synuclein (aSyn) in cerebrospinal fluid (CSF) in Parkinson's disease and related synucleinopathies have been reported, however, not consistently in all cross-sectional studies. To test the performance of one recently released human-specific enzyme-linked immunosorbent assay (ELISA) for the quantification of aSyn in CSF, we carried out a round robin trial with 18 participating laboratories trained in CSF ELISA analyses within the BIOMARKAPD project in the EU Joint Program - Neurodegenerative Disease Research. CSF samples (homogeneous aliquots from pools) and ELISA kits (one lot) were provided centrally and data reported back to one laboratory for data analysis. Our study showed that although factors such as preanalytical sample handling and lot-to-lot variability were minimized by our study design, we identified high variation in absolute values of CSF aSyn even when the same samples and same lots of assays were applied. We further demonstrate that although absolute concentrations differ between laboratories the quantitative results are comparable. With further standardization this assay may become an attractive tool for comparing aSyn measurements in diverse settings. Recommendations for further validation experiments and improvement of the interlaboratory results obtained are given.
authors.affiliation: Department of Neuropathology, University Medical Center, Göttingen, Germany. Electronic address: n.kruse@med.uni-goettingen.de.
authors.forename: Niels
authors.initials: N
authors.lastname: Kruse
authors.affiliation: Clinical Neurochemistry Laboratory, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Sahlgrenska University Hospital, Mölndal, Sweden.
authors.forename: Staffan
authors.initials: S
authors.lastname: Persson
authors.affiliation: Department of Neurology, Institut Investigacions Biomediques, Hospital de Sant Pau, Barcelona, Spain; Centro de Investigación Biomédica en Red en enfermedades Neurodegenerativas-CIBERNED, Madrid, Spain.
authors.forename: Daniel
authors.initials: D
authors.lastname: Alcolea
authors.affiliation: Department of Autoimmunology & Biomarkers, Statens Serum Institut, Copenhagen S, Denmark.
authors.forename: Justyna M C
authors.initials: JM
authors.lastname: Bahl
authors.affiliation: Neurochemistry Laboratory, Department of Neurology, Faculty of Medicine, CHUC-Centro Hospitalar e Universitário de Coimbra, CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.
authors.forename: Ines
authors.initials: I
authors.lastname: Baldeiras
authors.affiliation: Department of Neuroscience (DINOGMI), Clinical Neurology Unit, Genoa, Italy.
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Capello
authors.affiliation: Centre for Memory Disturbances and Alzheimer's Centre-Laboratory of Clinical Neurochemistry, Department of Medicine, Section of Neurology, University of Perugia, Perugia, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Chiasserini
authors.affiliation: Neuropsychopharmacology Unit, IRCCS Cento S. Giovanni di Dio Fatebenefratelli, Brescia, Italy; Faculty of Psychology, eCampus University, Novedrate (Como), Italy.
authors.forename: Luisella
authors.initials: L
authors.lastname: Bocchio Chiavetto
authors.affiliation: Department of Neurology, University Medical Centre, Ljubljana, Slovenia.
authors.forename: Andreja
authors.initials: A
authors.lastname: Emersic
authors.affiliation: Reference Centre for Biological Markers of Dementia (BIODEM), Institute Born-Bunge, University of Antwerp, Antwerp, Belgium.
authors.forename: Sebastiaan
authors.initials: S
authors.lastname: Engelborghs
authors.affiliation: Department of Neuroscience, Health Science Institute, Dokuz Eylül University, Izmir, Turkey.
authors.forename: Erden
authors.initials: E
authors.lastname: Eren
authors.affiliation: Department of Neurology, Akershus University Hospital, Lørenskog, Norway.
authors.forename: Tormod
authors.initials: T
authors.lastname: Fladby
authors.affiliation: Laboratory of Alzheimer´s Neuroimaging and Epidemiology, IRCCS Centro S. Giovanni di Dio Fatebenefratelli, Brescia, Italy; Departments of Psychiatry and Internal Medicine, University Hospitals and University of Geneva, Geneva, Switzerland.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Frisoni
authors.affiliation: Centro de Investigación Biomédica en Red en enfermedades Neurodegenerativas-CIBERNED, Madrid, Spain; Instituto de Neurociencias de Alicante, Universidad Miguel Hernández-CSIC, Sant Joan d´Alcant, Spain.
authors.forename: María-Salud
authors.initials: MS
authors.lastname: García-Ayllón
authors.affiliation: Department of Neuroscience, Health Science Institute, Dokuz Eylül University, Izmir, Turkey.
authors.forename: Sermin
authors.initials: S
authors.lastname: Genc
authors.affiliation: 3rd Neurology Department, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Olymbia
authors.initials: O
authors.lastname: Gkatzima
authors.affiliation: Department of Autoimmunology & Biomarkers, Statens Serum Institut, Copenhagen S, Denmark; Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense C, Denmark.
authors.forename: Niels H H
authors.initials: NH
authors.lastname: Heegaard
authors.affiliation: Genomed, Diagnósticos de Medicina Molecular, Instituto de Medicina Molecular, Edificio Egas Moniz, Lisbon, Portugal.
authors.forename: André M
authors.initials: AM
authors.lastname: Janeiro
authors.affiliation: Institute of Neuroimmunology, Slovak Academy of Sciences, Bratislava, Slovakia.
authors.forename: Branislav
authors.initials: B
authors.lastname: Kováčech
authors.affiliation: Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, The Netherlands; Department of Laboratory Medicine, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: H Bea
authors.initials: HB
authors.lastname: Kuiperij
authors.affiliation: Neurochemistry Laboratory, Department of Neurology, Faculty of Medicine, CHUC-Centro Hospitalar e Universitário de Coimbra, CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Leitão
authors.affiliation: Department of Neurology, Institut Investigacions Biomediques, Hospital de Sant Pau, Barcelona, Spain; Centro de Investigación Biomédica en Red en enfermedades Neurodegenerativas-CIBERNED, Madrid, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Lleó
authors.affiliation: Instituto de Medicina Molecular, Edificio Egas Moniz, Lisbon, Portugal; Instituto Gulbenkian de Ciência, Oeiras, Portugal.
authors.forename: Madalena
authors.initials: M
authors.lastname: Martins
authors.affiliation: Instituto de Medicina Molecular, Edificio Egas Moniz, Lisbon, Portugal.
authors.forename: Mafalda
authors.initials: M
authors.lastname: Matos
authors.affiliation: Department of Neurology, Akershus University Hospital, Lørenskog, Norway.
authors.forename: Hanne M
authors.initials: HM
authors.lastname: Mollergard
authors.affiliation: Department of Neuroscience (DINOGMI), Clinical Neurology Unit, Genoa, Italy.
authors.forename: Flavio
authors.initials: F
authors.lastname: Nobili
authors.affiliation: Clinical Neurochemistry Laboratory, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Sahlgrenska University Hospital, Mölndal, Sweden.
authors.forename: Annika
authors.initials: A
authors.lastname: Öhrfelt
authors.affiliation: Centre for Memory Disturbances and Alzheimer's Centre-Laboratory of Clinical Neurochemistry, Department of Medicine, Section of Neurology, University of Perugia, Perugia, Italy.
authors.forename: Lucilla
authors.initials: L
authors.lastname: Parnetti
authors.affiliation: Neurochemistry Laboratory, Department of Neurology, Faculty of Medicine, CHUC-Centro Hospitalar e Universitário de Coimbra, CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.
authors.forename: Catarina Resende
authors.initials: CR
authors.lastname: de Oliveira
authors.affiliation: Department of Neurology, University Medical Centre, Ljubljana, Slovenia.
authors.forename: Uros
authors.initials: U
authors.lastname: Rot
authors.affiliation: Centro de Investigación Biomédica en Red en enfermedades Neurodegenerativas-CIBERNED, Madrid, Spain; Instituto de Neurociencias de Alicante, Universidad Miguel Hernández-CSIC, Sant Joan d´Alcant, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Sáez-Valero
authors.affiliation: Reference Centre for Biological Markers of Dementia (BIODEM), Institute Born-Bunge, University of Antwerp, Antwerp, Belgium.
authors.forename: Hanne
authors.initials: H
authors.lastname: Struyfs
authors.affiliation: Department of Autoimmunology & Biomarkers, Statens Serum Institut, Copenhagen S, Denmark.
authors.forename: Julia T
authors.initials: JT
authors.lastname: Tanassi
authors.affiliation: BioLegend, Inc., Dedham, MA, USA.
authors.forename: Peggy
authors.initials: P
authors.lastname: Taylor
authors.affiliation: 3rd Neurology Department, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Magda
authors.initials: M
authors.lastname: Tsolaki
authors.affiliation: ADx NeuroSciences NV, Gent, Belgium.
authors.forename: Eugeen
authors.initials: E
authors.lastname: Vanmechelen
authors.affiliation: Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, The Netherlands; Department of Laboratory Medicine, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Marcel M
authors.initials: MM
authors.lastname: Verbeek
authors.affiliation: Institute of Neuroimmunology, Slovak Academy of Sciences, Bratislava, Slovakia.
authors.forename: Norbert
authors.initials: N
authors.lastname: Zilka
authors.affiliation: Clinical Neurochemistry Laboratory, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Sahlgrenska University Hospital, Mölndal, Sweden.
authors.forename: Kaj
authors.initials: K
authors.lastname: Blennow
authors.affiliation: Clinical Neurochemistry Laboratory, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Sahlgrenska University Hospital, Mölndal, Sweden; Department of Molecular Neuroscience, UCL Institute of Neurology, London, UK.
authors.forename: Henrik
authors.initials: H
authors.lastname: Zetterberg
authors.affiliation: Department of Neuropathology, University Medical Center, Göttingen, Germany; Paracelsus-Elena-Klinik, Kassel, Germany; Department of Neurosurgery, University Medical Center, Göttingen, Germany.
authors.forename: Brit
authors.initials: B
authors.lastname: Mollenhauer
mesh_terms: D015415:Biomarkers / Q000134:cerebrospinal fluid; D004797:Enzyme-Linked Immunosorbent Assay; D005060:Europe; D005260:Female; D006801:Humans; D007391:International Cooperation; D008297:Male; D019636:Neurodegenerative Diseases / Q000134:cerebrospinal fluid*; D010300:Parkinson Disease / Q000134:cerebrospinal fluid*; D015203:Reproducibility of Results; D014481:United States; D051844:alpha-Synuclein / Q000134:cerebrospinal fluid*
chemical_list: D015415:Biomarkers; D051844:alpha-Synuclein
keywords: Alpha-synuclein; Biomarker; Cerebrospinal fluid; ELISA; Validation