GFAP and supranuclear palsy, progressive, 1: To investigate the presence of astrogliosis, microgliosis and synaptic engulfment by astrocytes and microglia in PSP, we immunostained 4-μm-thick FFPE sections from PSP and control frontal cortex with antibodies against astrocytes (glial fibrillary acidic protein, GFAP), microglia (CD68 or P2RY12), presynapses (synaptophysin (SYO) or synapsin-1 (SYN1)) and phosphorylated tau (AT8; Fig. 3a,b).