Abstract
Background:
Neuronal damage is the morphological substrate of persisting neurological disability. Neurofilaments (Nf) are specific cytoskeletal proteins of neurons and their quantification has shown encouraging results as a biomarker for axonal injury.
Methods:
We aimed at comparing a widely used conventional ELISA for Nf light chain (NfL) with an electrochemiluminescence-based method (ECL assay) and a newly developed single-molecule array (Simoa) method in clinically relevant cerebrospinal fluid (CSF) and serum samples.
Results:
Analytical sensitivity was 0.62 pg/mL for Simoa, 15.6 pg/mL for the ECL assay, and 78.0 pg/mL for the ELISA. Correlations between paired CSF and serum samples were strongest for Simoa (r=0.88, p<0.001) and the ECL assay (r=0.78, p<0.001) and weaker for ELISA measurements (r=0.38, p=0.030). CSF NfL measurements between the platforms were highly correlated (r=1.0, p<0.001). Serum NfL levels were highly related between ECL assay and Simoa (r=0.86, p<0.001), and this was less visible between ELISA-ECL assay (r=0.41, p=0.018) and ELISA-Simoa (r=0.43, p=0.013). Multiple sclerosis (MS) patients had significantly higher serum NfL levels than controls when measured with Simoa (p=0.001) but not with the other platforms.
Conclusions:
We found Simoa to be more sensitive than ELISA or the ECL assay. Our results support the feasibility of quantifying NfL in serum; the results correlate with the more-established CSF NfL test. The highly sensitive Simoa technology deserves further studies in larger patient cohorts to clarify whether serum NfL could be used in the future to measure disease severity and determine prognosis or response to treatment interventions in neurological diseases.
Acknowledgments:
We thank M. Limberg for technical assistance.
Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: The study was supported by grants from the Swiss MS Society, Swiss National Science Foundation (Grant/Award Number: ‘320030_160221’), Bayer (Switzerland) AG, Genzyme, Novartis, Swedish Research Council, VINNOVA, the Torsten Söderberg Foundation, the Knut and Alice Wallenberg Foundation, Swedish State Support for Clinical Research, and Frimurarestiftelsen.
Employment or leadership: None declared.
Honorarium: None declared.
Competing interests: The funding organization(s) played no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.
References
1. Teunissen CE, Khalil M. Neurofilaments as biomarkers in multiple sclerosis. Mult Scler 2012;18:552–6.10.1177/1352458512443092Search in Google Scholar PubMed
2. Deisenhammer F, Egg R, Giovannoni G, Hemmer B, Petzold A, Sellebjerg F, et al. EFNS guidelines on disease-specific CSF investigations. Eur J Neurol 2009;16:760–70.10.1111/j.1468-1331.2009.02595.xSearch in Google Scholar PubMed
3. Teunissen CE, Iacobaeus E, Khademi M, Brundin L, Norgren N, Koel-Simmelink MJ, et al. Combination of CSF N-acetylaspartate and neurofilaments in multiple sclerosis. Neurology 2009;72:1322–9.10.1212/WNL.0b013e3181a0fe3fSearch in Google Scholar PubMed
4. Norgren N, Karlsson JE, Rosengren L, Stigbrand T. Monoclonal antibodies selective for low molecular weight neurofilaments. Hybrid Hybridomics 2002;21:53–9.10.1089/15368590252917647Search in Google Scholar PubMed
5. Gaiottino J, Norgren N, Dobson R, Topping J, Nissim A, Malaspina A, et al. Increased neurofilament light chain blood levels in neurodegenerative neurological diseases. PLoS One 2013;8:e75091.10.1371/journal.pone.0075091Search in Google Scholar PubMed PubMed Central
6. Rissin DM, Kan CW, Campbell TG, Howes SC, Fournier DR, Song L, et al. Single-molecule enzyme-linked immunosorbent assay detects serum proteins at subfemtomolar concentrations. Nat Biotechnol 2010;28:595–9.10.1038/nbt.1641Search in Google Scholar PubMed PubMed Central
7. Wilson DH, Rissin DM, Kan CW, Fournier DR, Piech T, Campbell TG, et al. The simoa HD-1 analyzer: a novel fully automated digital immunoassay analyzer with single-molecule sensitivity and multiplexing. J Lab Autom 2015 [Epub ahead of print].10.1177/2211068215589580Search in Google Scholar PubMed
8. Teunissen CE, Petzold A, Bennett JL, Berven FS, Brundin L, Comabella M, et al. A consensus protocol for the standardization of cerebrospinal fluid collection and biobanking. Neurology 2009;73:1914–22.10.1212/WNL.0b013e3181c47cc2Search in Google Scholar PubMed PubMed Central
9. Valentin MA, Ma S, Zhao A, Legay F, Avrameas A. Validation of immunoassay for protein biomarkers: bioanalytical study plan implementation to support pre-clinical and clinical studies. J Pharm Biomed Anal 2011;55:869–77.10.1016/j.jpba.2011.03.033Search in Google Scholar PubMed
10. Lee JW, Devanarayan V, Barrett YC, Weiner R, Allinson J, Fountain S, et al. Fit-for-purpose method development and validation for successful biomarker measurement. Pharm Res 2006;23:312–28.10.1007/s11095-005-9045-3Search in Google Scholar PubMed
11. Andreasson U, Perret-Liaudet A, van Waalwijk van Doorn LJ, Blennow K, Chiasserini D, Engelborghs S, et al. A Practical Guide to Immunoassay Method Validation. Front Neurol 2015;6:179.10.3389/fneur.2015.00179Search in Google Scholar
12. Lu CH, Macdonald-Wallis C, Gray E, Pearce N, Petzold A, Norgren N, et al. Neurofilament light chain: a prognostic biomarker in amyotrophic lateral sclerosis. Neurology 2015;84:2247–57.10.1212/WNL.0000000000001642Search in Google Scholar
13. Lundberg M, Curbo S, Reiser K, Masterman T, Braesch-Andersen S, Arestrom I, et al. Methodological aspects of ELISA analysis of thioredoxin 1 in human plasma and cerebrospinal fluid. PLoS One 2014;9:e103554.10.1371/journal.pone.0103554Search in Google Scholar
14. Kuhle J, Pohl C, Mehling M, Edan G, Freedman MS, Hartung HP, et al. Lack of association between antimyelin antibodies and progression to multiple sclerosis. N Engl J Med 2007;356:371–8.10.1056/NEJMoa063602Search in Google Scholar
15. Brickshawana A, Hinson SR, Romero MF, Lucchinetti C, Guo Y, Buttmann M, et al. Investigation of the KIR4.1 potassium channel as a putative antigen in patients with multiple sclerosis: a comparative study. Lancet Neurol 2014;13:795–806.10.1016/S1474-4422(14)70141-3Search in Google Scholar
16. Teunissen CE, Malekzadeh A, Leurs C, Bridel C, Killestein J. Body fluid biomarkers for multiple sclerosis–the long road to clinical application. Nat Rev Neurol 2015;11:585–96.10.1038/nrneurol.2015.173Search in Google Scholar PubMed
©2016 Walter de Gruyter GmbH, Berlin/Boston
