The intervertebral disc is located between adjacent vertebral bodies, and is composed of peripheral annulus fibrosus, central gelatinous nucleus pulposus tissue and a thin layer of transparent cartilage endplates at the upper and lower ends. With the growth of age or genetic factors, it is easy to cause intervertebral disc degeneration.
intervertebral disc degeneration refers to the abnormal response of progressive structural failure mediated by cells. Clinically, it often develops into a series of painful spinal diseases, such as cervical spondylosis, discogenic low back pain, spinal stenosis and lumbar disc herniation. Because it is the largest non vascular structure in human body, it is difficult to repair itself after degradation or damage, and it is irreversible.
with the rise of the concept of regenerative medicine, stem cell therapy has been widely concerned in sports injury and orthopedic degenerative diseases. In view of this feature, researchers began to use stem cells to intervene in the process of intervertebral disc degeneration, in order to slow down the process of intervertebral disc degeneration or repair the disc.
intervertebral disc degeneration will lead to the imbalance of the internal environment, the loss of hydration, inflammation and extracellular matrix, which will lead to the reduction of intervertebral disc height and the destruction of annulus fibrosus. Stem cells have the ability of multi-directional differentiation and secretion of cytokines, which can repair and immune regulate the intervertebral disc from many aspects.
stem cells and nucleus pulposus cells can differentiate into nucleus pulposus like cells under non-contact co culture, and then produce proteoglycan and type II collagen. It was found that the proliferation of mesenchymal stem cells could be reduced by direct contact with mesenchymal stem cells.
activated stem cells can secrete a variety of cytokines, including anti-inflammatory factors and growth factors, promote the growth of intervertebral disc cells and the synthesis of extracellular matrix of nucleus pulposus, play an anti-inflammatory and nutritional role, thus improving the internal environment and relieving clinical symptoms.
Yim RL has systematically included 24 animal experiments for analysis: 862 intervertebral discs were treated with stem cell therapy. The results showed that stem cells from various sources successfully inhibited the development of intervertebral disc degeneration and significantly increased the height of intervertebral disc.
another mate analysis of Wang et al. Included a total of 22 animal experimental research projects. The results showed that the intervertebral disc height index increased, the expression of type II collagen mRNA increased, and the histological level of intervertebral disc degeneration decreased. It was considered that stem cell transplantation could effectively alleviate or prevent the degeneration process.
in recent years, some scholars have used stem cell therapy in clinical trials. In 2017, Noriega et al. Conducted a randomized controlled clinical study in which 24 patients with discogenic low back pain received allogeneic mesenchymal stem cell transplantation. After one year of follow-up, the symptoms and MRI disc degeneration were improved.
in the same year, Pettine et al. Implemented stem cell therapy on 26 patients with indications for disc replacement. MRI confirmed that the degree of intervertebral disc degeneration improved 12 months after transplantation. After 3 years of follow-up, the Oswestry disability index and visual analog score scores of 20 subjects were significantly improved, and no complications occurred. Luanban