Longevity & AgingClonal CD8 T Cells Invade Parkinson's Disease Brain and Team Up With Reactive Astrocytes
Researchers at Columbia University used single-nucleus RNA sequencing, spatial transcriptomics, and T cell receptor (TCR) sequencing on postmortem brain tissue from Parkinson's disease (PD) patients to map immune cell activity in the substantia nigra (SN). They found that CD8+ T cells were significantly enriched in the PD SN, showed clonal expansion, and carried TCR sequences homologous to those known to react against α-synuclein. Spatially, these T cells co-localized with a disease-associated astrocyte population marked by CD44. Silencing CD44 in cultured astrocytes dampened neuroinflammatory gene expression, identifying CD44 as a potential therapeutic target. The study provides the most detailed molecular portrait yet of adaptive immune activity within the human PD brain.
