兔骨髓间充质干细胞修复膝关节软骨缺损的实验研究

Experimental study on regeneration of articular cartilage defects in rabbits with allogeneic bone marrow mesenchymal stem cells

目的研究由同种异体兔骨髓间充质干细胞(MSCs)诱导分化的软骨细胞和聚乳酸-聚乙醇酸共聚物(PLGA)双层支架构建复合体对兔软骨缺损的修复作用。方法用密度梯度离心法和贴壁培养法获得5月龄兔骨髓来源间充质干细胞,在体外培养并进行分化诱导后作为种子细胞复合双层PLGA构建成复合体。36只兔在股骨髁间制造骨软骨缺损模型,分成三组,A组植入复合体,B组植入单纯双层PLGA支架,C组植入自体骨软骨。第24周取材进行大体观察、组织学检查和Wakitani评分。结果 A组及C组植入物愈合良好,组织学检查见Ⅰ、Ⅱ型胶原纤维形成。A组可见透明软骨修复。Wakitani评分A组2.75,B组7.00,C组1.98,A、C组与B组间统计学分析单项指标得分差异有统计学意义(P<0.05),A组与C组间差异无统计学意义(P>0.05)。结论诱导兔MSCs+PLGA双层支架能较好地修复兔膝关节骨软骨损伤。

Objective To investigate the effects of mesenchymal stem cells （MSCs）combined with poly（ lactie-co-glycolic acid） （PLGA） in repairing articular cartilage defect in rabbit. Methods MSCs were isolated and purified from five-month rabbit, in vitro amplificated and cultured. The treated cells were seeded into PLGA. Cartilage defects were made at the intereondylar fossa of the distal femur in 36 rabbits and randomly divided into 3 groups, group A were implanted with the complex, group B were implanted with PLGA, and group C were implanted with autologous bone-cartilage graft. After 24 weeks the specimens were examined histologically for morphologic features, and stained immunohistochemically for type II collagen. Wakitani grade was assessed. Results The implants of group A and group C healed well. Hyaline cartilage was found in group A. Wakitani grade of group A was 2.75, that of group B was 7. 00, and of group C was 1.98. There was significant difference among all groups in statistics （ P 〈 0. 05）. There was no significant difference between group A and group C （P 〉 0. 05 ）. Conclusions The rabbit＇ s articular cartilage defect could be repaired well with MSCs and PLGA complex.