Endothelial barrier integrity, tight-junction expression, phosphorylated tau (pTau), and Aβ42/Aβ40 production and distribution between compartments were assessed using immunofluorescence imaging and ELISA.<h4>Results</h4>The neurospheroid-grafted endothelial barrier construct captured key AD-associated phenotypes. Here, MAPT is linked to Alzheimer disease.