The increase in chemokines promoting T cell migration and extravasation along with the enhanced infiltration of CD4+ T cells into the brain parenchyma in FTLD-tau and mostly in PiD (that has brain atrophy and abnormalities in brain vasculature43,44), as well as the association between CD8+ T cell infiltration and pTau epitopes, altogether highlight a previously underestimated feature of the disease. The gene discussed is CD4; the disease is Brain atrophy.