EVs can cause constitutive tau proteins to change into their harmful versions when proteins like tau are released.366 Earlier, AD development was thought to be caused by interaction between brain cells.367 Numerous studies have found that EVs potentially transport harmful biomaterials inside the brain in recent years.368 For instance, endothelial cells, which are crucial parts of the blood-brain barrier (BBB), have been found to produce EVs that include β-amyloid (Fig. 6a) 343. Here, MAPT is linked to Alzheimer disease.