Mesenchymal Stem Cells for Treatment of Refractory Chronic Graft-versus-host Disease

• The efficacy of treatment for refractory cGVHD [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  The response criteria include complete response (CR), part response (PR), stable disease(SD) and progressive disease(PD). CR:cGVHD symptoms and signs disappear; PR:cGVHD symptoms and signs improve; SD:cGVHD symptoms and signs remain (without improvement or deterioration);PD: cGVHD symptoms and signs deteriorate.
  
  

• acute and late toxic side effects of MSCs treatment [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]
  Toxic side effects of treatment includes acute toxicity and late side effects. Acute toxicity principally involves the heart,live and kidney. Late toxic side effects involves principally the development of secondary tumors and relapse of the primary disease.
  
  

• infections [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]
  Infections will be mainly focused within the first 100 days after MSCs treatment.
  
  

Allogeneic hematopoietic stem cell transplantation(allo-HSCT) can cure many hematologic diseases. Although great progress has been made in the prevention and treatment of side effects associated with transplantation,chronic graft-versus-host disease(cGVHD) remains an important complication that occurs in about 50% patients. The mortality of cGVHD and its complication could reach up to 50%,and cGVHD seriously influence the quality of life. At present, glucocorticoids and cyclosporine (CsA) are the first line treatment of cGVHD, but their effective rates are only 50%. If first line treatment is ineffective, second line drugs would be taken, such as mycophenolate mofetil(MMF)and rituximab. The effective rates of second line drugs are 30%-61%. The effective rates and prognosis of refractory cGVHD are even worse.

Mesenchymal stem cells (MSCs) are a form of multipotent adult stem cells that can be isolated from bone marrow (BM), adipose tissue, and cord blood. Clinical applications of human MSCs are evolving rapidly with goals of improving hematopoietic engraftment, preventing and treating GVHD after allo-HSCT and so on. However, the efficacy of treatment of refractory cGVHD using expanded BM-derived MSCs from a third-party donor is rarely reported. If such treatment could be shown to be effective and safe, BM-derived MSCs could potentially be used as an universal donor material. This would have a major impact because the generation of donor-specific MSCs is time-consuming, costly, and often impractical if the clinical status of a patient is urgent.

In the present study, the investigators will prospectively evaluate the efficacy and safety of ex-vivo-expanded BM-derived MSCs from third-party donors in treating patients with refractory cGVHD.