Neuromyelitis Optica and Astrocyte Pathology

Neuromyelitis optica (NMO) due to aquaporin 4 (AQP4) antibodies (Ab) is associated with astrocyte destruction. To identify features of astrocyte pathology in NMO, investigators evaluated 23 autopsy cases with a clinical and pathologic diagnosis of NMO.

In addition to astrocytic lysis and AQP4 loss, they observed hypertrophic and dystrophic astrocytes, cytoplasmic vacuolation, and evidence of astrocytopathy extended beyond lesion edges. Rosenthal fibers (protein-aggregates within astrocytes) were similarly observed both within and outside demyelinated regions. Within reactive astrocytes, AQP4 mRNA transcription was upregulated. Astrocytopathic changes occurred both within and outside demyelinated tissues, in areas that lacked AQP4 loss or com…