Mesenchymal Stem Cell-Macrophage Choreography Supporting Spinal Cord Repair.

Spinal cord injury results in destructive events that lead to tissue loss and functional impairments. A hallmark of spinal cord injury is the robust and persistent presence of inflammatory macrophages. Mesenchymal stem cells (MSCs) are known to benefit repair of the damaged spinal cord often associated with improved functional recovery. Transplanted MSCs immediately encounter the abundance of inflammatory macrophages in the injury site. It is known that MSCs interact closely and reciprocally with macrophages during tissue healing. Here, we will review the roles of (transplanted) MSCs and macrophages in spinal cord injury and repair. Molecular interactions between MSCs and macrophages and the deficiencies in our knowledge about the underlying mechanisms will be reviewed. We will discuss possible ways to benefit from the MSC-macrophage choreography for developing repair strategies for the spinal cord.