A novel study on the immunomodulatory effect of umbilical cord derived mesenchymal stem cells pretreated with traditional Chinese medicine Asarinin

Allogeneic hematopoietic stem cell transplantation (HSCT) remains the key for the treatment of malignant hematological diseases, and acute graft-versus-host disease (aGVHD) that might occur after allogenic transplantation can be life threatening and promote disease recurrence. GVHD damages the various parts of the body by upregulating T helper 1 cytokines (Th1) cytokines and stimulating CD4?CD8 + T cells. GVHD can exhibit significant immunoregulatory effects, but could be easily affected by the mesenchymal stem cells (MSC) environment, and hence the MSC immunosuppressive effects on GVHD remain unpredictable. Hence, to better understand the role of MSC in the prevention and treatment of GVHD, umbilical cord derived mesenchymal stem cells (UC-MSC) were pretreated with Chinese medicine Asarinin and IFN-gamma. In the mix lymphocyte reaction, we found that Asarinin pretreated UC-MSC can exert significantly greater inhibition towards the proliferation of CD4 and CD8 + T cells, down-regulate Th1 type cytokines, up-regulate Th2 type cytokines, and reduce the inflammatory damage to liver, lung and intestine of aGVHD mice model. Moreover, Asarinin can cooperate with IFN-gamma to promote UC-MSC to secrete indoleamine 2,3-dioxygenase (IDO). Our findings establish that Asarinin pre-treated UC-MSC can significantly promote the immunosuppressive effects of MSC on aGVHD after hematopoietic stem cell transplantation.