MAPT and Alzheimer disease: In line with this Aβ-tau synergetic theory, our AD-like NHP model induced by hTau overexpression in monkey hippocampi did display scattered intracellular Aβ accumulation, occasional parenchymal Aβ plaque-like deposits, and significant Aβ clearance deficits, as revealed by immunostaining and CSF Aβ measurements.