[Mesenchymal stem cells for treatment of graft-versus-host disease]

Steroid-refractory graft-versus-host disease (SR-GVHD) is one of the most important complication post allogeneic hematopoietic stem cell transplantation. Mesenchymal stem cells (MSCs) possess characteristic immunomodulatory features which are beneficial in the salvage treatment for SR-GVHD. Following the first case report in 2004, numerous clinical trials have shown encouraging results with MSC infusions for treating SR-GVHD. In Japan, two clinical trials have achieved favorable results, and subsequently in September 2015, MSC infusion became the first approved allogeneic cell therapy for SR-GVHD. Currently, MSCs are available at limited institutes, and all patients infused with MSCs have been registered in the post marketing survey. Based on the results of this survey, the establishment of guidelines for the proper use of MSCs is anticipated. Moreover, several groups have reported the efficacy of MSCs for chronic GVHD or GVHD prophylaxis. In the present review, current issues regarding the use of MSCs in the management of GVHD are summarized.