title: Neuromyelitis optica: a demyelinating disease characterized by acute destruction and regeneration of perivascular astrocytes.
abstract: BACKGROUND
  A serum antibody directed against astrocytes is present in a high proportion of patients with neuromyelitis optica (NMO). The pathogenicity of the antibody is uncertain because no consistent astrocyte lesion is known to occur in NMO.
  
  
  OBJECTIVE
  To determine whether there is an astrocyte lesion in NMO and if this differs from astrocyte changes in multiple sclerosis (MS).
  
  
  METHODS
  Astrocyte pathology in early (still-myelinated) lesions and subacute NMO and MS lesions was examined immunohistochemically and in sections stained for astrocytes using routine histological techniques.
  
  
  RESULTS
  Demyelination in early NMO lesions is accompanied by oligodendrocyte apoptosis in a pattern identical to that seen in MS and this is preceded by an abrupt destruction of perivascular astrocytes. Reparative astrogliosis is effected by a population of unipolar, new astrocytes. Evidence of a different type of astrocyte lesion was found in MS.
  
  
  CONCLUSIONS
  The findings add to experimental evidence that the antibody is pathogenic. They also raise the possibility that demyelination in MS may be a bystander effect of an astrocyte lesion, i.e. that MS is not a disease primarily of myelin and oligodendrocytes.
authors.affiliation: The Institute of Clinical Neurosciences, Department of Medicine, The University of Sydney, NSW, Australia.
authors.forename: John D E
authors.initials: JD
authors.lastname: Parratt
authors.forename: John W
authors.initials: JW
authors.lastname: Prineas
mesh_terms: D000328:Adult; D000368:Aged; D051401:Aquaporin 4 / Q000276:immunology; D001253:Astrocytes / Q000473:pathology*; D001344:Autopsy; D001921:Brain / Q000473:pathology; D003165:Complement System Proteins / Q000032:analysis; D003711:Demyelinating Diseases / Q000473:pathology*; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006801:Humans; D007136:Immunoglobulins / Q000032:analysis; D007150:Immunohistochemistry; D007249:Inflammation / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000473:pathology; D009186:Myelin Sheath / Q000378:metabolism; D009416:Nerve Regeneration / Q000502:physiology; D009471:Neuromyelitis Optica / Q000473:pathology*; D009836:Oligodendroglia / Q000473:pathology; D009900:Optic Nerve / Q000473:pathology; D016612:Paraffin Embedding; D013116:Spinal Cord / Q000473:pathology; D055815:Young Adult
chemical_list: D051401:Aquaporin 4; D005904:Glial Fibrillary Acidic Protein; D007136:Immunoglobulins; D003165:Complement System Proteins