Abstract:

BACKGROUND: Cytoskeleton is a carrier of cell growth, and its pore caliber is one of the most important factors to affect the curative effect of tissue engineered spinal cord.
OBJECTIVE: To explore the optimal pore size of poly lactic-co-glycolic acid (PLGA) scaffolds for tissue engineered spinal cord by in vitro culture of neural stem cells (NSCs) and various pore sizes of PLGA scaffolds.
METHODS: 50 µL (cell number 10¹⁰/L) NSCs suspension at passage 1 was separately seeded on 200-300 µm, 400-500 µm PLGA stent for 7 days. Two sorts of tissue engineered spinal cord were constructed in vitro. Thirty rat models of spinal cord injury were established, and then assigned to 3 groups. The detect sites of these models were filled with above-mentioned spinal cord immediately, but the blank control was not treated with any material. The cells growth and proliferation implanted on PLGA were observed by phase contrast microscope and scanning electron microscope. Relative number of NSCs in two tissue engineered spinal cords was measured by MTT assay. The effects of transplantation with tissue engineered spinal cord were evaluated by the BBB scale.
RESULTS AND CONCLUSION: Neural stem cells implanted on different pore size scaffolds were seen growing by phase contrast microscope and scanning electron microscope, with good histocompatibility. After 7-day coculture, absorbance was similar between 200-300 µm PLGA and 400-500 µm PLGA groups (P > 0.05). These indicated that the pore size had no effects on NSC number. At week 4 following transplantation, in the blank control group, neural function was recovered to different degrees in the 200-300 µm PLGA and 400-500 µm PLGA groups. BBB motor functional score was significantly increased (P < 0.05). The pore size of 200-300 µm utilized in fabricating tissue engineered spinal cord has the best transplantation effect as compared to others.