Role of IL-6 in regulation of inflammation and stem cell differentiation in CNS trauma

Abstract

Interleukin-6 (IL-6) has been demonstrated to play a pivotal role in CNS trauma as a proinflammatory cytokine which regulates inflammatory response. Not only being a mediator of inflammation, but IL-6 induces neural stem/progenitor cells to undergo astrocytic differentiation selectively in the injured CNS. These effects are considered to coordinate to prevent the CNS repair after traumatic injury. Consistently, we previously reported that the administration of anti-IL-6 receptor antibody (MR16-1) immediately after spinal cord injury in mice decreased the number of invading inflammatory cells and the severity of connective tissue scar formation, and led to improved functional recovery. These findings suggest that neutralization of IL-6 signaling in the acute phase of SCI will be beneficial for CNS repair. A critical merit of this anti-IL-6 receptor antibody is that humanized antibody to human IL-6 receptor (MRA; Atlizumab) has already been reshaped. However, there are several studies which show beneficial aspects of IL-6 signaling in the pathology of CNS trauma. Further investigation of the mechanisms how MR16-1 reduces tissue damage should be required for clinical application.