Pluripotency of mesenchymal cells derived from synovial fluid in patients with temporomandibular joint disorder.

Mesenchymal stem cells are an interesting source of material for regenerative medicine. The present study aimed at characterizing the phenotype and differentiation potential of adherent synovial fluid-derived cells from temporomandibular joint (TMJ) disorder patients. Synovial fluid collection takes place during TMJ cavity irrigation arthrocentesis under local anesthesia. The synovial fluid-derived adherent cells were fibroblast-like and spindle-shaped. Ex vivo-expanded synovial fluid-derived cells were shown to express STRO-1 and CD146, previously found to be present in bone marrow mesenchymal stem cells. Further, they were identified as being capable of differentiating into a variety of cell types including osteoblasts, chondrocytes, adipocytes, and neurons. The present study demonstrates that human pluripotent cells can be isolated from synovial fluid. These synovial fluid-derived cells cannot only be derived from a very accessible resource, but are also capable of providing sufficient cells for potential clinical applications. These cells may play a role in the regenerative response during arthritic diseases and are promising candidates for developing novel cell-based therapeutic approaches for postnatal skeletal tissue repair.