Ilham Y Abdi1, Nour K Majbour1, Eline A J Willemse2, Wilma D J van de Berg3, Brit Mollenhauer4,5, Charlotte E Teunissen2, Omar M El-Agnaf1. 1. Neurological Disorders Research Centre, Qatar Biomedical Research Institute (QBRI), Hamad Bin Khalifa University (HBKU), Doha, Qatar. 2. Neurochemistry Laboratory, Department of Clinical Chemistry, Amsterdam Neuroscience, Amsterdam University Medical Center, Amsterdam, Netherlands. 3. Section Clinical Neuroanatomy and Biobanking, Department of Anatomy and Neurosciences, Amsterdam Neuroscience, Amsterdam University Medical Center, Vrije University Amsterdam, Amsterdam, Netherlands. 4. Paracelsus-Elena-Klinik, Klinikstraße, Kassel, Germany. 5. Department of Neurology, University Medical Center Göttingen, Göttingen, Germany.
Abstract
Background: The role of cerebrospinal fluid (CSF) alpha-synuclein as a potential biomarker has been challenged mainly due to variable preanalytical measures between laboratories. To evaluate the impact of the preanalytical factors contributing to such variability, the different subforms of alpha-synuclein need to be studied individually. Method: We investigated the effect of exposing CSF samples to several preanalytical sources of variability: (1) different polypropylene (PP) storage tubes; (2) use of non-ionic detergents; (3) multiple tube transfers; (4) multiple freeze-thaw cycles; and (5) delayed storage. CSF oligomeric- and total-alpha-synuclein levels were estimated using our in-house sandwich-based enzyme-linked immunosorbent assays. Results: Siliconized tubes provided the optimal preservation of CSF alpha-synuclein proteins among other tested polypropylene tubes. The use of tween-20 detergent significantly improved the recovery of oligomeric-alpha-synuclein, while multiple freeze-thaw cycles significantly lowered oligomeric-alpha-synuclein in CSF. Interestingly, oligomeric-alpha-synuclein levels remained relatively stable over multiple tube transfers and upon delayed storage. Conclusion: Our study showed for the first-time distinct impact of preanalytical factors on the different forms of CSF alpha-synuclein. These findings highlight the need for special considerations for the different forms of alpha-synuclein during CSF samples' collection and processing.
Background: The role of cerebrospinal fluid (CSF) alpha-synuclein as a potential biomarker has been challenged mainly due to variable preanalytical measures between laboratories. To evaluate the impact of the preanalytical factors contributing to such variability, the different subforms of alpha-synuclein need to be studied individually. Method: We investigated the effect of exposing CSF samples to several preanalytical sources of variability: (1) different polypropylene (PP) storage tubes; (2) use of non-ionic detergents; (3) multiple tube transfers; (4) multiple freeze-thaw cycles; and (5) delayed storage. CSF oligomeric- and total-alpha-synuclein levels were estimated using our in-house sandwich-based enzyme-linked immunosorbent assays. Results: Siliconized tubes provided the optimal preservation of CSF alpha-synuclein proteins among other tested polypropylene tubes. The use of tween-20 detergent significantly improved the recovery of oligomeric-alpha-synuclein, while multiple freeze-thaw cycles significantly lowered oligomeric-alpha-synuclein in CSF. Interestingly, oligomeric-alpha-synuclein levels remained relatively stable over multiple tube transfers and upon delayed storage. Conclusion: Our study showed for the first-time distinct impact of preanalytical factors on the different forms of CSF alpha-synuclein. These findings highlight the need for special considerations for the different forms of alpha-synuclein during CSF samples' collection and processing.
Authors: Lara Blömeke; Marlene Pils; Victoria Kraemer-Schulien; Alexandra Dybala; Anja Schaffrath; Andreas Kulawik; Fabian Rehn; Anneliese Cousin; Volker Nischwitz; Johannes Willbold; Rebecca Zack; Thomas F Tropea; Tuyen Bujnicki; Gültekin Tamgüney; Daniel Weintraub; David Irwin; Murray Grossman; David A Wolk; John Q Trojanowski; Oliver Bannach; Alice Chen-Plotkin; Dieter Willbold Journal: NPJ Parkinsons Dis Date: 2022-06-02