The early stages of Parkinson’s disease (PD) are characterized by the misfolding and aggregation of alpha-synuclein (α-syn) in the brain. While these events are linked to changes in cellular homeostasis, the precise mechanisms leading to the later selective degeneration of dopaminergic neurons are not fully understood, largely due to limitations in current PD models. To overcome these challenges, we have developed induced pluripotent stem cell (iPSC)-derived midbrain organoids as a more advanced and accurate model to investigate the dynamics of early α-syn pathology.
In our experimental setup, we induce endogenous α-syn aggregation in these midbrain organoids by treating them with α-syn preformed fibrils (PFFs). We have already performed initial analyses of the early cellular responses five days after PFF treatment using immunostainings and single-cell RNA sequencing.
To further elucidate the intricate cellular responses within their native three-dimensional context, we now plan to perform spatial transcriptomics at single-cell resolution using Stereo-seq on these PFF-treated midbrain organoids. The data generated from the Stereo-seq analysis will then be integrated with our existing single-cell transcriptomic data. This integrative approach is designed to significantly increase the resolution for localizing transcripts within the organoid structure. More importantly, it will enable us to study the response of specific cell types, in direct relation to their spatial location within the organoid and their proximity to the distributed α-syn fibrils.
This project will leverage our established iPSC-derived midbrain organoid model and the power of spatially-resolved transcriptomics to provide novel insights into the molecular mechanisms driving the initial stages of α-syn pathology and cellular vulnerability in a human-relevant context.
