Study Rationale: Currently existing seed amplification assays (SAAs) in which pathological protein clumps from patient samples are amplified such that they can be more easily detected for the diagnosis of Parkinson's disease (PD) are not quantitative enough to follow disease progression or treatments. One possibility to improve SAAs is to convert them into a format in which the protein clumps can be individually counted, so-called digital assays. Here we will bring to maturity such a digital assay through further development and optimization of assay throughput and sensitivity.
Hypothesis: We will demonstrate that we can push the sensitivity of quantitative seed amplification assay (SAA)-based diagnosis of PD from CSF into the range where it can be applied in practice, and we will also explore a novel type of plate-based SAA for less invasive sample matrices, e.g. skin and saliva.
Study Design: We have already demonstrated that our microdroplet-based SAA is able to amplify patient-derived fibrils and now we need to optimize sensitivity. We will achieve this through an increase in the experimental throughput and the quality and homogeneity of the amplification through improved hardware. We will also introduce a pre-amplification step into the workflow in which the concentration of protein clumps in CSF is increased in a well-defined manner before entering the quantitative (digital) assay. We will also test new experimental conditions that we have invented for SAAs from skin and saliva.
Impact on Diagnosis/Treatment of Parkinson’s disease: Being able to follow the concentrations of alpha-synuclein aggregates in various body fluids and tissues of patients, ideally as little invasive as possible, will be a game-changing development in PD diagnosis and for the development of therapies. This will allow to monitor progress or regress of the disease.
Next Steps for Development: The next step would be the validation with a large cohort of patients in different stages, whereby each patient is followed over a longer time period. If such a study would show that our assay works, then the commercial development of the method would be the next step.