Regenerative Therapies in Cartilage and Bone: Current Patents, Technologies, and Emerging Applications

Regenerative medicine is a powerful interdisciplinary tool that allows novel therapeutic approaches to be developed for diseases with no effective treatment, and its potential has been substantially enhanced by recent advances. We review the latest strategies, patented and/or under clinical trial, for the development of therapies based on the formation of new bone and cartilaginous tissue from stem cells to replace injured, diseased, or poorly-developed tissue. Mesenchymal stem cells are the most widely used cell types. Strategies generally involve the extraction of stem cells from the patient, their expansion in culture, their reprogramming and, finally, implantation in the patient of alreadydifferentiated cells along with the matrix they form or another matrix or artificial scaffolding. In order to guarantee treatment success, the biomaterial transferred to the patients must be adequately anchored and sufficiently biocompatible. Patented protocols for stem cell differentiation include: using different types of exogenous factors or of specific ligands against receptors associated with various signaling routes, inducing differentiation by physical methods, or stimulating differentiation of the patient's stem cell population in situ. The complex range of methods and protocols in the literature suggest that we are at the starting point of an emerging area that promises to deliver a new platform superior to other technologies currently considered to be at the vanguard.