Objective: To assess intravitam frequency and type of misfolded α-synuclein aggregates (syn-seeds) in participants with clinically defined primary tauopathies, such as progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS), by α-synuclein seed amplification assay (synSAA).
Background: Amprion’s synSAA can distinguish two types of syn-seeds in cerebrospinal fluid (CSF): Type1 are associated with Lewy bodies (LB) and predominantly found in Parkinson’s disease and dementia with LB, and Type2 are associated with glial cytoplasmic inclusions predominantly found in multiple system atrophy (MSA). Clinically defined synucleinopathies and tauopathies (particularly PSP) are often misdiagnosed in early disease stages due to complex clinical presentations with overlapping symptoms.
Method: Pathology-confirmed cases included 41 subjects from University of Pennsylvania; clinical cases included 161 participants (123 PSP, 33 CBS, 5 undetermined tauopathy [UT]) from Paracelsus-Elena Klinik, a specialized movement disorder clinic in Kassel, Germany. Clinical diagnoses were finalized after comprehensive clinical evaluation according to established criteria. CSF samples were analyzed by synSAA at Amprion. Positive samples (synSAA+) with high (≥45,000RFU) and intermediate (≥3,000RFU & <45,000RFU) maximum fluorescence indicate Type1 and Type2 syn-seeds, respectively. Kinetic amplification parameters were analyzed.
Results: 92.8% (13/14) of synSAA+ pathology-confirmed cases had LB disease and/or Alzheimer’s disease co-pathology. Syn-seeds were detected in 28.1% of clinically defined tauopathy cases. 87.9% of synSAA+ clinically defined PSP (29) and 100% of synSAA+ clinically defined CBS (11) and UT (1) cases were found to have Type1 syn-seeds. Interestingly, 9.1% of synSAA+ clinically defined PSP (3) cases were found to have Type2 syn-seeds.
Conclusion: In agreement with prior studies using pathology-confirmed samples, synSAA is highly specific for syn-seeds in the context of co-pathologies. synSAA can identify syn-seeds intravitam to aid early identification of synuclein pathology to both accelerate the time to final diagnosis and aid differential diagnosis.
To cite this abstract in AMA style:
C. Farris, S. Weber, Y. Ma, M. Starke, D. Irwin, A. Siderowf, B. Mollenhauer, L. Concha. Identification of Alpha-synuclein Pathology in Primary Tauopathies by Seed Amplification Assay [abstract]. Mov Disord. 2026; 41 (suppl 1). https://www.mdsabstracts.org/abstract/identification-of-alpha-synuclein-pathology-in-primary-tauopathies-by-seed-amplification-assay/. Accessed October 1, 2026.« Back to 2026 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/identification-of-alpha-synuclein-pathology-in-primary-tauopathies-by-seed-amplification-assay/