MAPT and Alzheimer disease: Some studies with APP-transgenic mice (such as APPswe/PS1 Tg mice and 4- or 12-month old 3xTg-AD) showed that systemic LPS injection triggers microglia activation, leading to neuroinflammation, Aβ accumulation and/or tau pathology, synaptic loss and neurodegeneration with learning impairments, memory deficits, and cognitive decline [65,66,67].