Bone marrow mesenchymal stem cells (BMSCs) are multipotent nonhematopoietic progenitor cells capable of differentiating into multiple lineages,such as bone,fat,and cartilage.BMSCs preferentially home to the damaged tissue and are beneficial to tissue repair.In vitro studies have shown that they do not induce immune response and can inhibit immune cells involved in alloantigen recognition and elimination.In animal models,BMSCs have been shown to induce peripheral tolerance and migrate to injured tissues,where they can inhibit the release of pro-inflammatory cytokines and promote the survival of damaged cells.The unique properties of MSCs suggest a role in cell therapy and treatment of immunomediated diseases.