Because of their hypoimmunogenicity and their potential to create an immunosuppressive local microenvironment through the production of TGF-β, PGE-2, and HLA-G molecules [8], [38], BM-MSC are successfully employed to prevent graft-versus-host disease (GvHD) [11], [39], [40]. Here, HLA-G is linked to graft versus host disease.