Anti-Aquaporin 4 antibodies present in patients with Neuromyelitis Optica reduces the water permeability of astrocytes plasma membrane.

LUCIANA MELAMUD; JUAN FERNADEZ; VALERIA RIVAROLA; CLAUDIA CAPURRO; ANDRES VILLA

Barcelona, España

Congreso; 10th International Congress of Neuroimmunology Sitges; 2010

Sociedad Española de Neurología

The current study evaluates the consequences of NMO-IgG binding to the plasma membrane expression pattern of AQP4 and its water permeability in well-differentiated astrocytes cultures. Immunocytochemical analysis and fluorescence videomicroscopy cell volume measurements showed that, independently of complement activation, long-term exposition to NMO positive sera induced a loss of NMO-IgG signal in the plasma membrane together with a significant reduction in water permeability. Furthermore, NMO-IgG affects a specific pool of AQP4. These results suggest that NMO-IgG-induced AQP4 down-regulation is a specific mechanism that may account for at least part of the pathogenic process.