Microglia, like a double-edged sword in AD, on the one hand, gather around NFTs in the brains of AD patients, engulf Aβ (Hickman et al., 2008), Tau (Luo et al., 2015), and abnormal synapses (Hansen et al., 2018), thereby exerting a neuroprotective effect. This evidence concerns the gene MAPT and Alzheimer disease.