Increased Plasma Interleukin-32 Expression in Patients with Neuromyelitis Optica

Purpose Neuromyelitis optica (NMO) is a chronic inflammatory demyelinating disease of the central nervous system (CNS). The pathogenesis of NMO remains unclear. IL-32 is emerging as a critical molecule in the pathophysiology of immune-mediated chronic inflammatory diseases. Whether IL-32 levels are elevated in NMO patients is unclear. We aimed to determine whether IL-32 levels are elevated in NMO patients and explore its relationship with IL-6, IL-17, and Expanded Disability Status Scale (EDSS) scores. Methods Plasma IL-32 alpha, IL-6 and IL-17A were measured by enzyme-linked immunosorbent assay in NMO (n=26), MS (n=23) and 22 healthy controls. Results We found IL-32 alpha levels were higher in NMO patients compared with MS (p=0.020) and healthy controls (p=0.00001). IL-32 alpha levels were increased in MS patients compared with controls (p=0.009). IL-32 alpha positively correlated with IL-6 and IL-17A levels and EDSS scores in NMO patients. Conclusions In summary, plasma IL-32 alpha levels are associated with inflammatory responses in NMO patients.