GZMK and Alzheimer disease: CD8+ T cells have also been found in the leptomeninges of AD patients9, and despite recent studies showing the abundance of meningeal immune cells and the role of CNS borders during neurodegenerative and neuroinflammatory diseases15, our results reveal that the number of CD103–CD8+ Trm cells does not change significantly and GrK secretion does not increase in the meninges, suggesting the brain is the main site of CD8+ Trm cell dysregulation.