Fig. 7.

Reactive astrogliosis in two degenerative diseases. a High magnification image of autopsy specimen from a person with longstanding Alzheimer’s disease immunohistochemically stained for GFAP. Section of cerebral cortex shows an amyloid senile plaque with a pale unstained center (Aβ) ringed by dense layers of reactive astrocytic processes (arrows) that circumferentially surround the plaque as if forming a scar-like barrier around it. b High magnification image of autopsy specimen from a person with Creutzfeldt–Jakob disease (CJD) transmissible spongiform encephalopathy. Section of cerebral cortex shows pronounced neuron loss and severe diffuse reactive astrogliosis. Most of the cortex is packed with gemistocytic astrocytes, while spongiform change is relatively minimal in this area. Scale bars a, b 10 μm