CD4 and Alzheimer disease: Compared to those in controls, activated CD8 T cells, activated dendritic cells, effector memory CD8 T cells, immature B cells, MDSCs, natural killer cells, natural killer T cells, plasmacytoid dendritic cells, regulatory T cells, type 1 T helper cells, and type 17 T helper cells were significantly elevated in AD, while effector memory CD4 T-cell levels were significantly decreased (Fig. 5A).