[Disruption of blood-brain barrier in multiple sclerosis and neuromyelitis optica].

Pathological destruction of the blood-brain barrier(BBB) has been considered to be the initial key step of disease process in multiple sclerosis (MS) and neuromyelitis optica (NMO). The pathological findings using autopsy brain section from patients with secondary progressive (SP) MS or relapsing MS demonstrated a leaky BBB in active lesions and our recent data also showed that the sera from patients with relapsing MS or SPMS can induce the BBB breakdown. Recently, the disease-specific autoantibody "anti-aquaporin 4(AQP4) antibodies" was detected in the sera of NMO patients. Because the circulating anti-AQP4 antibodies need to pass through BBB in order to reach the astrocytic endfeets, where AQP4 localized, our recent studies demonstrated the detailed molecular mechanism of the BBB disruption in NMO.