Stem cell-mediated regeneration of the intervertebral disc: cellular and molecular challenges

Regenerative medicine and stem cells hold great promise for intervertebral disc (IVD) disease. The therapeutic implications of utilizing stem cells to repair degenerated discs and treat back pain are highly anticipated by both the clinical and scientific communities. Although the avascular environment of the IVD poses a challenge for stem cell-mediated regeneration, neuroprogenitor cells have been discovered within degenerated discs, allowing scientists to revisit the hostile environment of the IVD as a target for stem cell therapy. Issues now under investigation include the timing of cell delivery and manipulation of stem cells to make them more efficient and adaptive in the IVD niche. This review covers the mechanisms underlying disc degeneration as well as the molecular and cellular challenges involved in directing stem cells to the desired cell type for intradiscal transplantation.