Mesenchymal stem cells targeting the GVHD

Acute graft-versus-host disease (GVHD) occurs after allogeneic hematopoietic stem cell transplant and is a reaction of donor immune cells against host tissues. About 35%-50% of hematopoietic stem cell transplant (HSCT) recipients will develop acute GVHD. It is associated with considerable morbidity and mortality, particularly in patients who do not respond to primary therapy, which usually consists of glucocorticoids(steroids). Most of the available second-line and third-line treatments for steroid-refractory acute GVHD induce severe immunodeficiency, which is commonly accompanied by lethal infectious complications. Mesenchymal stem cells (MSCs) have been shown to mediate immunomodulatory effects. The recently elucidated immunosuppressive potential of mesenchymal stem cells has set the stage for their clinical testing as cellular immunosuppressants, MSCs have been used in patients with steroid-refractory acute GVHD, and encouraging responses have been obtained in many studies. The utility of MSCs for the treatment of GVHD is becoming clear.