Here (below) is a Swedish study about alpha-synuclein in the diagnostics of PD-related diseases. The small number of patients in the bioMuse study limited the conclusions. However, when bioMuse was started we did not have yet this Swedish study. Prof. Claassen has now the skills to do seed amplification and this is important to demonstrate if ATH434 works.

Parkinsonism Relat Disord

. 2023 Aug 14;105807.

doi: 10.1016/j.parkreldis.2023.105807. Online ahead of print.

α-Synuclein seed amplification assay as a diagnostic tool for parkinsonian disorders

Bárbara Fernandes Gomes ¹, Carly M Farris ², Yihua Ma ², Luis Concha-Marambio ², Russ Lebovitz ², Bengt Nellgård ³, Keti Dalla ³, Julius Constantinescu ⁴, Radu Constantinescu ⁴, Johan Gobom ⁵, Ulf Andreasson ⁵, Henrik Zetterberg ⁶, Kaj Blennow ⁵

Affiliations expand

• PMID: 37591709

DOI: 10.1016/j.parkreldis.2023.105807Free article

Abstract

Introduction: Synucleinopathies such as Parkinson's disease (PD) and multiple system atrophy (MSA) can be challenging to diagnose due to the symptom overlap with, for example, atypical parkinsonisms like progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). Seed amplification assays (SAA), developed for the detection of α-synuclein (αSyn) aggregates in CSF, have been successful when used as a biomarker evaluation for synucleinopathies. In this study, we investigated the potential of this assay to not only detect αSyn seeds in CSF, but also discriminate between movement disorders.

Methods: The αSyn-SAA was tested in a Scandinavian cohort composed of 129 CSF samples from patients with PD (n = 55), MSA (n = 27), CBD (n = 7), and PSP (n = 16), as well as healthy controls (HC, n = 24).

Results: The αSyn seed amplification assay (αSyn-SAA) was able to correctly identify all PD samples as positive (sensitivity of 100%) while also discriminating the PD group from HC (70.8% specificity, p < 0.0001) and tauopathies [CBD (71% specificity) and PSP (75% specificity), p < 0.0001)]. The αSyn-SAA was also able to identify almost all MSA samples as positive for αSyn aggregation (sensitivity of 92.6%). In general, this assay is able to discriminate between the synucleinopathies and tauopathies analyzed herein (p < 0.0001) despite the overlapping symptoms in these diseases.

Conclusion: These findings suggest the αSyn-SAA is a useful diagnostic tool for differentiating between different parkinsonian disorders, although further optimization may be needed.

Keywords: Alpha-synuclein; Atypical parkinsonian disorders; Biological assay; Biomarker; Parkinson's disease.