Hans S. Keirstead, Gabriel Nistor, Giovanna Bernal, Minodora Totoiu, Frank Cloutier, Kelly Sharp, and Oswald Steward
Human embryonic stem cells (hESCs) hold tremendous therapeutic promise, provided they can be harnessed to fulfill specific cellular or tissue functions. This week, Keirstead et al. show that after spinal cord injury in the rat, neuronal loss is compounded by the loss of oligodendrocytes both near and distant from the injury site. Using a 42 d protocol, the authors differentiated the H7 hESC line into OPCs. They then transplanted the oligodendrocyte progenitor cell (OPCs) into the site of a contusion injury that caused moderate hindlimb motor impairment. Cells transplanted at 7 d or 10 months after injury survived, differentiated into oligodendrocytes, and traveled a few millimeters from the site. However, only those transplanted 1 week after injury went on to remyelinate axons and improve locomotion.