磷酸三钙-透明质酸-Ⅰ型胶原-骨髓基质细胞复合修复骨缺损的实验研究

目的观察由磷酸三钙人工骨(β-tricalciumphosphate,β-TCP)、透明质酸(hyaluronicacid,HA)、型胶原(type collagen,COL-)复合物作为诱导后的骨髓基质细胞(marrowstromalcells,MSCs)载体修复兔桡骨骨缺损的能力及作为自体骨移植替代物的可能性。方法获取新西兰大白兔MSCs,体外诱导培养后与β-TCP、HA、COL-结合形成复合物。将6月龄新西兰大白兔30只,手术制备双侧桡骨2cm骨缺损,8周后随机分为A、B及C组,A组(n=27侧),植入β-TCP-HA-COL--MSCs;B组(n=27侧),植入自体骨;C组(n=6侧),缺损空置作为空白对照。用扫描电镜观察β-TCP-HA-COL-结构。于4、8和12周各时间点分别处死动物6、9和15只;4、8周时A、B组各6侧,12周时A、B组各15侧;C组8周时6侧。进行大体观察、X线摄片、HE染色及无机质含量测定,对A、B组12周时标本进行成骨面积及生物力学测试,比较各组骨缺损的修复效果。结果MSCs在体外生长稳定,增殖能力强,可被诱导为成骨细胞。β-TCP-HA-COL-复合物呈多孔结构。各组各时间点大体观察、X线片、组织学及生物力学测试结果显示,随着时间的延长A、B组骨缺损可被修复,空白对照组不能修复。12周时成骨面积、生物力学测试,A、B组差异无统计学意义(P>0.05)。A组中的无机质含量在4、8和12周分别为75%、57%和42%。结论

AN EXPERIMENTAL STUDY ON REPAIRING BONE DEFECT WITH COMPOSITE OF β-TRICALCIUM PHOSPHATE-HYALURONIC ACID-TYPE I COLLAGEN-MARROW STROMAL CELLS

OBJECTIVE: To observe the ability to repair bilateral radius bone defect with the composite of beta-tricalcium phosphate (PTCP), hyaluronic acid (HA), type I collagen (COL-I) and induced marrow stromal cells (MSCs), and to investigate the feasibility of the composite as a bone substitute material. METHODS: The MSCs of the New Zealand white rabbits were induced into ostoblasts, then combined with beta-TCP, HA and COL-I. Thirty New Zealand white rabbits were made the bilateral radius bone defects of 2 cm and divided into groups A, B and C. After 8 weeks, beta-TCP-HA-COL-I-MSCs (group A, n=27 sides), autograft (group B, n=27 sides)and no implant (group C as control, n=6 sides) were implanted into the areas of bilateral radius bone defects, respectively. The structure of the composite was observed by scanning electron microscope. The repairing effect was observed by gross, histomorphology, X-ray examination, and the degradation rate of inorganic substance at 4, 8 and 12 weeks. The ostogenic area and biomechanics of group A were compared with those of group B at 12 weeks. RESULTS: The MSCs could stably grow in vitro, relatively rapidly proliferated, and could be induced into the ostoblasts. The composite was porous. The results of gross, histomorphology and X-ray showed that the bone defects were perfectly repaired in group A and group B, but not in group C. The ostogenic area or biomechanics had no statistically significant difference between groups A and B (P> 0.05). The weight of inorganic substance in group A were 75%, 57% and 42% at 4, 8, 12 weeks, respectively. CONCLUSION: MSCs can be used as seed cells in the bone tissue engineering. The composite has porous structure, no reactions of toxicity to the tissue and rapid degradation, and it is an ideal carrier of seed cells. The beta-TCP-HA-COL-I-MSCs composite has the high ability of repairing bone defect and can serve as an autograft substitute material.