MAPT and tauopathy: The predominant glial tau association of IBNC has similarities to the tau gliopathy reported for argyrophilic grain disease, progressive supranuclear palsy and corticobasal degeneration [22] but, in contrast to the predominant 3R tauopathy found in IBNC, these human neurodegenerations are all 4R tauopathies (Table 2).