Harnessing the Potential of Mesenchymal Stem Cells for IVD Regeneration.

Intervertebral disc (IVD) degeneration is one of the leading causes of low back pain, which affects a large proportion of the global population at a huge socioeconomic burden. Current treatments focus primarily on symptomatic pain relief or surgery, but offer relatively poor long-term efficacy as they fail to address the pathogenesis of the underlying IVD degeneration. In order to offer improved clinical outcomes, a number of biological and regenerative therapies are currently being developed which target the disease at a molecular and cellular level and aim to restore IVD function. This review focusses on the considerations for development of cell-based therapies for IVD regeneration. In particular it focusses on the identification of novel progenitor cell populations within the IVD and the application of mesenchymal stem cells (MSCs) in IVD tissue engineering, which are being increasingly studied as they offer huge potential for tissue regeneration. Additionally it highlights how the growing understanding of the molecular phenotype of IVD cells is allowing tailored differentiation strategies to be developed and how MSC source and choice of growth factor influences cell phenotype and appropriate tissue formation. Finally, it reviews the range of functional biomaterials being developed to aid MSC delivery and differentiation, and discusses the potential impact the degenerate IVD microenvironmental niche may have on MSC behaviour following implantation.