Abstract
IL-6 is known as a multifunctional cytokine regulating immune response and inflammation. Many studies have shown that IL-6 affects the nervous system. However, the involvement of IL-6 in the nervous system, particularly in the peripheral nervous system (PNS), remains incompletely understood. Here, we assessed the effect of rat anti-mouse IL-6 receptor monoclonal antibody (MR16-1) in the treatment of experimental sciatic nerve crush injury in mice. The mice were given a single intraperitoneal injection (2 mg/head) of MR16-1 or Rat IgG as a control antibody the day before nerve crush injury. Treatment with MR16-1 significantly promoted sciatic functional recovery, and histological remyelination was greater than that by Rat IgG treatment. Furthermore, IL-6 expression was confirmed in the nerve after nerve crush injury in the Rat IgG group, but not in the MR16-1 group. MR16-1 also decreased the number of infiltrating macrophages. Additionally, IL-6 decreased the expression of nerve growth factor (NGF) mRNA in cultured primary mouse Schwann cells, and this decrease in NGF expression by IL-6 was reversed with MR16-1. These findings suggest that MR16-1 may inhibit the infiltration of macrophages and the decrease of NGF in Schwann cells, resulting in the acceleration of nerve regeneration.
