Increased Soluble C 5b‐9 in CSF of Neuromyelitis Optica

Neuromyelitis optica ( NMO ) and multiple sclerosis ( MS ) are two of the autoimmune inflammatory demyelinating diseases in the central nervous system. Complement is thought to have an important role in pathogenesis of these diseases, especially in NMO . However, the change of terminal complement complex ( TCC , C 5b‐9) in patients with NMO is still unclear. Cerebrospinal fluid ( CSF ) C 3a, C 5a, s C 5b‐9 were measured by enzyme‐linked immunosorbent assay in patients with NMO ( n  = 26), MS ( n  = 25) and other neurological disease ( OND , n  = 19). CSF levels of C 5a in patients with NMO were higher than patients with OND ( P  =   0.006). Increased CSF s C 5b‐9 were found in the patients with NMO compared with patients with MS ( P  =   0.029) and OND ( P  =   0.0001). CSF s C 5b‐9 in patients with MS were also higher than patients with OND ( P  =   0.030). Patients with NMO revealed a trend to an increased disease disability with increased CSF s C 5b‐9 during relapse but not in MS ( NMO : P  =   0.006, MS: P  =   0.097). CSF levels of s C 5b‐9 are increased in patients with NMO and reflect the activation of complement in NMO .