Fig. 2 |. CD8⁺ T cells enter the brain in patients with AD.

a, Confocal imaging of cerebral amyloid angiopathy (CAA) in the post-mortem brain of a patient with AD from cohort 3 shows CD8⁺ T cells in the perivascular space of Aβ⁺ blood vessels with cerebral amyloid angiopathy in three AD-affected hippocampi. Arrowheads indicate CD8⁺ T cells; asterisks indicate blood vessel lumen. Scale bars, 20 μm. b, Higher numbers of CD8⁺ T cells were detected in AD-affected than control hippocampi. Mean ± s.e.m.; unpaired two-sided t-test with Welch’s correction. c, A CD8⁺ T cell is shown associated with MAP2⁺ neuronal processes. d, CD8⁺ T cells are localized to the leptomeninges and adjacent to hippocampal AP plaques. Scale bar, 100 μm. Data in c, d were replicated in three independent experiments.