CD8A and Alzheimer disease: Remarkably, CD45RA+ effector memory CD8 T cells (also called TEMRA CD8 T cells) are increased in the CSF and blood of patients diagnosed with mild cognitive impairment or AD, showed a higher propensity to secrete IFN-γ, and their numbers were positively correlated with worse cognitive performance, thus indicating its potential value as a biomarker of disease progression and severity [35].