Role of T cells in Parkinson’s disease

Parkinson’s disease (PD) is the fastest growing neurodegenerative disorder worldwide and is characterised by the aggregation of α-synuclein and the progressive loss of dopaminergic neurons. Current therapies provide only symptomatic relief without altering disease progression and the challenges of PD diagnosis due to subtle early symptoms highlight the urgent need for a deeper understanding of disease mechanisms. Emerging evidence indicates that T cells of the adaptive immune system play a critical role in PD. This review examines the evidence for T-cell infiltration in the PD brain and the recognition of PD-associated autoantigens. We further examine experimental findings that provide insight into the mechanisms underlying T-cell-mediated neurodegeneration. Finally, we explore the emerging potential of T cells as both diagnostic biomarkers and therapeutic targets, highlighting their relevance for the development of novel disease-modifying strategies in PD.