聚碳酸亚丙酯/壳聚糖纳米纤维三维多孔支架复合骨髓间充质干细胞修复兔骨缺损

Propylene carbonate/chitosan nanofiber porous scaffolds composited with bone marrow mesenchymal stem cell for bone defect repair in rabbits

背景:骨组织工程细胞移植技术是近年来的研究热点,支架材料是其重要组成部分,同时也是三大要素中最有望取得突破性进展的环节,随着组织工程材料工艺的革新,有望为更好地修复骨缺损带来新的希望。目的:评价聚碳酸亚丙酯/壳聚糖纳米纤维(propylene carbonate/chitosan nanofibers,PPC/CSNF)三维多孔支架复合骨髓间充质干细胞(bone marrow mesenchymal stem cell,BMSCs)修复兔股骨髁部骨缺损的能力。方法:二次相分离法制作PPC/CSNF复合三维多孔支架,将第3代的BMSCs种植到复合材料上。36只新西兰大白兔右侧股骨髁制作直径6mm深10mm骨缺损,于缺损处实验组植入复合BMSCs的PPC/CSNF多孔支架,对照组植入单纯PPC/CSNF多孔支架,标准组于兔髂后上棘取自体松质骨移植于缺损部位,空白组不做处理。术后第4,8,12周取材,通过大体观察、放射学检查和组织学检查等方法评价其修复缺损情况。结果与结论:实验组放射学评价与标准组无显著差异,两组结果均优于对照组(P<0.05);实验组大体标本与标准组基本一致;实验组组织学检查新骨生成速度、生成量优于对照组(P<0.05);空白组不能自行修复骨缺损,最后缺损由纤维组织充填。结果显示PPC/CSNF多孔支架具有较好的细胞和组织相容性,复合兔BMSCs能加速新骨形成,可用于修复兔股骨髁部骨缺损。

BACKGROUND： Cell transplantation technique for bone tissue engineering is a hotspot in recent years. Scaffold material is an important component, which can obtain the most promising breakthrough among the three elements. With the innovative development of tissue engineering material technology, it is expected to bring a hope for better repair of bone defects. OBJECTIVE： To investigate the effect of propylene carbonate/chitosan nanofibers （PPC/CSNF） porous scaffolds combined with bone marrow mesenchymal stem cells （BMSCs） to repair bone defects in the femoral condyle of rabbits. METHODS： PPC/CSNF composite porous scaffold was processed by in situ phase separation, the third passage of BMSCs were cultured on the composite scaffold. Thirty-six New Zealand white rabbits were divided into experimental group, standard group, control group and blank group at random. A bone defect was made, 6 mm in diameter and 10 mm in depth, in the right femoral condyle of each rabbit. Then PPC/CSNF/BMSCs compound was planted into the defected position in the experimental group; autogenous bone in the standard group; PPC/CSNF scaffolds in the control group; and nothing in the blank group. The curative effect was evaluated by general observation, radiographic examination and histologic analysis at the 4th, 8th, and 12th week after operation. RESULTS AND CONCLUSION： Roentgenographically, the bone defects in the experimental groups and criterion groups exhibited new bone formation increased with time, which were apparently superior to that in the control group （P 0.05）. The quality of new bone formation was significantly different between the experimental and the control groups by histologic analysis. In the blank group, bone defect could not be repaired without proper treatment, finally filling only with fibrous tissue. PPC/CSNF porous scaffold composited with BMSCs has a good ability to accelerate the formation of new bone, and repair bone defect finally.