It was found that the intravenous injection of paired helical filaments (PHF)–tau protein from a human AD brain into 5×FAD transgenic mice could exacerbate neuroinflammation and Aβ and tau pathologies, showing increased p-tau immunoreactivity and increased deposits of Aβ40 and Aβ42 [66]. This evidence concerns the gene MAPT and Alzheimer disease.