title: Reduction in serum aquaporin-4 antibody titers during development of a tumor-like brain lesion in a patient with neuromyelitis optica: a serum antibody-consuming effect?
abstract: Neuromyelitis optica (NMO) is an inflammatory demyelinating disease of the CNS with severe involvement of the optic nerve and spinal cord. Highly specific serum IgG autoantibodies (NMO-IgG) that react with aquaporin-4 (AQP4), the most abundant CNS water channel protein, are found in patients with NMO. However, in vivo evidence combining the results of AQP4 antibody serum levels and brain pathology is lacking. We report a patient with NMO whose AQP4 antibody levels decreased simultaneously with clinical deterioration caused by the development of a tumor-like brain lesion. In the seminecrotic biopsied brain lesion, there was activated complement complex, whereas only very scattered immunoreactivity to AQP4 protein was detectable. The decrease in serum AQP4 antibody levels and the loss of AQP4 in the tumor-like lesion could represent a "serum antibody-consuming effect" during lesion formation.
authors: From the Departments of Neurology (FA-D) and Radiology (WK), SMZ-Ost Donauspital; Karl Landsteiner Institute for Neuroimmunological and Neurodegenerative Disorders (FA-D, WK); Institute of Neurology (RH, HB) and Center for Brain Research, Department of Neuroimmunology (HL), Medical University of Vienna, Vienna, Austria; and Neuroimmunology Group, Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom (PW, AV).
authors: Fahmy
authors: F
authors: Aboulenein-Djamshidian
authors: Romana
authors: R
authors: Höftberger
authors: Patrick
authors: P
authors: Waters
authors: Wolfgang
authors: W
authors: Krampla
authors: Hans
authors: H
authors: Lassmann
authors: Herbert
authors: H
authors: Budka
authors: Angela
authors: A
authors: Vincent
authors: Wolfgang
authors: W
authors: Kristoferitsch
mesh_terms: D000888:Antibodies, Anti-Idiotypic / Q000097:blood*; D051401:Aquaporin 4 / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D001932:Brain Neoplasms / Q000097:blood* / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008875:Middle Aged; D009471:Neuromyelitis Optica / Q000097:blood* / Q000175:diagnosis*
chemical_list: C496030:AQP4 protein, human; D000888:Antibodies, Anti-Idiotypic; D051401:Aquaporin 4; D015415:Biomarkers; D007074:Immunoglobulin G; C048844:anti-IgG