Progress with stem cell therapies for tendon tissue regeneration.

Chronic musculoskeletal pain is very prevalent, and accounts for major health-care expenses. Many of the present therapeutic modalities are only partially effective, and great interest is now posed on regenerative medicine. The authors discuss the role of a variety of regenerative medicine options to induce and favor regeneration and healing of tendon tissue, focusing on the role of mesenchymal stem cell therapy and their derivatives. Stem cells, tissue engineering, and growth factors are new strategies for tendon repair and regeneration. MSCs not only can differentiate in tendon cells, but also secrete several cytokines that modulate inflammation and tissue healing. Future studies should be undertaken to overcome current obstacles to clinical translation. Further investigation of cell source, isolation, expansion, and differentiation methods, characterization of the tenogenic differentiation pathways, and clarifications of tendon-specific molecular markers are required. The role of donor variability, tendon type, and anatomic location also requires further understanding and research.