MAPT and Alzheimer disease: In addition, CK2 expression was significantly increased in neurons in the hippocampus, astrocytes, and primary neurons transfected with human tau in AD patients (Rosenberger et al., 2016), and CK2 is localized to hyperphosphorylation sites of NFT and tau (e.g., Ser396/404) (Iimoto et al., 1990; Masliah et al., 1992).