Abstract:

BACKGROUND: Sodium hyaluronate, as the matrix material of intervertebral disc tissue engineering scaffolds, can provide proteoglycan attachment points and increase deposition of proteoglycan, to make enough large porosity allowing the seed cell ingrowth.
OBJECTIVE: To observe the effect of bone mesenchymal stem cells (BMSCs) mixed with sodium hyaluronate solution in repair of disc degeneration in rabbits. 　
METHODS: The animal mode of degenerative intervertebral disc was built in rabbits by aspirating the nucleus pulposus (L1-2 and L3-4) through an posterolateral approach. Two weeks later, the mixture of BMSCs and sodium hyaluronate were injected into L3-4 discs using micro-injection syringe as study group, while sodium hyaluronate alone was injected into L1-2 as control group. At 2, 4, 8, 12 weeks after injection, the rabbit intervertebral disc was determined by plain radiography and histology.
RESULTS AND CONCLUSION: The intervertebral disc height was reduced in control group, and gradually reduced in experiment group at 2 weeks after injection and then raised. There were significant differences in disc height index between two groups (P< 0.05). Pathological examination showed the structure of the inner annulus fibrosus was significantly preserved in the experiment group, and the boundary between the nucleus and annulus could be clearly visualized. The implanted BMSCs proliferated and the pathological grading scores were significantly higher than control group. Expression of type Ⅱ collagen was significantly greater in the experiment group than in control group (P < 0.05). BMSCs transplanted into intervertebral discs are shown to well survive and proliferate. The mixture of BMSCs and sodium hyaluronate could decelerate disc degeneration and repair the degenerated intervertebral discs.