Iba1 and GFAP immunostains were also performed on brainstem (midbrain) sections of both unimmunized and immunized PSP cases which revealed reactive microglia (Fig. 6, third row) and reactive astrocytes with hypertrophic cellular processes (Fig. 6, bottom row) in all PSP cases consistent with the high PSP-tau burden in these regions. Here, GFAP is linked to supranuclear palsy, progressive, 1.