Therefore, it is likely that the tau oligomers, which form prior to intracellular neurofibrillary tangles (NFTs), and represents an early stage in tangle formation, induce inflammation and trigger changes in BBB; thus, resulting in the transmigration of peripheral blood-borne cells into brain areas affected by neurofibrillary pathology in tauopathies. This evidence concerns the gene MAPT and tauopathy.