Session Information
Date: Monday, September 23, 2019
Session Title: Other
Session Time: 1:45pm-3:15pm
Location: Agora 2 West, Level 2
Objective: The goal of this study was to employ a novel highly sensitive dual-stain immunohistochemical (IHC) assay in the assessment of cutaneous pathological alpha-synuclein (aSyn) depositions in patients with idiopathic REM sleep behavior disorder (iRBD), Parkinson’s disease (PD), atypical parkinsonism and controls.The goal of this study was to employ a novel highly sensitive dual-stain immunohistochemical (IHC) assay in the assessment of cutaneous pathological alpha-synuclein (aSyn) depositions in patients with idiopathic REM sleep behavior disorder (iRBD), Parkinson’s disease (PD), atypical parkinsonism and controls.
Background: Development of therapeutic agents for PD is hampered by a lack of diagnostic tests that accurately identify patients with PD, especially early PD. While the definitive diagnosis of PD can only be made at autopsy upon demonstration of pathological central nervous system aSyn, recent findings suggest that detection of pathological aSyn deposition in skin biopsies can be used to identify patients with PD during life.
Method: Formalin-fixed, paraffin embedded paravertebral C7 area skin punch biopsies of 79 subjects (28 iRBD, 20 PD, 10 atypical parkinsonism, 21 controls) were bisected. A single slide from each bisected block was analyzed for pathological aSyn on the automated BenchMark ULTRA system using a novel chromogenic dual-stain IHC assay that enabled high contrast visualization of pathological aSyn.
Results: With two slides from one skin biopsy area per subject, pathological aSyn was observed in 60% of PD, 71% of iRBD, 20% of atypical parkinsonism, and 5% of control subjects. Full results based upon extensive sectioning of tissue blocks will be presented.
Conclusion: A novel IHC assay was developed to detect aSyn pathology associated with PD in the peripheral tissue. This tool has the potential to be developed into a diagnostic assay for synucleinopathies and selection of patients for clinical trials targeting aggregated aSyn.
To cite this abstract in AMA style:
T-S. Tsao, A. Al-Qassabi, A. Racolta, KI. Taylor, W. Zago, RB. Postuma, S. Dziadek. Automated Immunohistochemical Detection of Skin Depositions of Pathological alpha-Synuclein in Idiopathic REM Sleep Behavior Disorder and Parkinsonism [abstract]. Mov Disord. 2019; 34 (suppl 2). https://www.mdsabstracts.org/abstract/automated-immunohistochemical-detection-of-skin-depositions-of-pathological-alpha-synuclein-in-idiopathic-rem-sleep-behavior-disorder-and-parkinsonism/. Accessed June 14, 2025.« Back to 2019 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/automated-immunohistochemical-detection-of-skin-depositions-of-pathological-alpha-synuclein-in-idiopathic-rem-sleep-behavior-disorder-and-parkinsonism/