Cell-Based Therapies for Degenerative Disc Diseases

Intervertebral discs degeneration are responsible for most of cases of low back pain, which affects millions of people worldwide. Current clinical therapies for degenerative disc diseases involve medications or physiotherapy for mild to moderate degeneration, and surgeries for severe degeneration. However, current treatments aim to remove symptoms sometimes at the cost of mobility instead of restoring the biological function. Future therapy for disc repair is in development by biological strategies, including protein or growth factor injections, gene therapy or cell therapy approaches. Cell-based therapies provide the greatest hope, as it is a continuous source of cells and cytokine production, and the safety is superior compared to gene therapy. The choice of cell source includes chondrocytes, disc cells, embryonic stem cells, hematopoietic stem cells, and mesenchymal stem cells. Results of several clinical trials suggest that mesenchymal stem cells are the best choice of cell source for intervertebral discs regeneration. The remaining concern is that the harsh environment of the degenerated disc may have effect on the engraftment and differentiation of implanted cells. The timing of cell implantation may also have effect on the degree of disc regeneration, which may require an earlier intervention at mild to moderate level of disc degeneration to achieve satisfactory surgical outcome.