Gene therapy approaches for intervertebral disc degeneration

Review of the literature concerning the development of gene therapy approaches for the treatment of intervertebral disc degeneration. To provide an overview of gene therapy principles, summarize the results of completed gene therapy studies, and discuss considerations for the direction of future research. Intervertebral disc degeneration is characterized by progressive loss of the proteoglycan matrix in the nucleus pulposus. Exogenous growth factors have been shown to transiently increase matrix synthesis. Gene therapy offers exciting potential to induce and sustain endogenous production of growth factors within the intervertebral disc and thus possibly alter the degenerative course. Published and presented scientific literature was examined. Several in vitro and in vivo studies have documented the capacity of gene therapy to favorably modify the biologic functions of intervertebral disc cells with the delivery of the cDNA for various growth factors. Currently, investigators are exploring the efficacy and safety of gene therapy in animal models of degeneration. With promising initial results and an immense potential clinical impact, gene therapy approaches for treatment of intervertebral disc degeneration will continue to receive dedicated research efforts.