兔髁突来源骨髓间充质干细胞体内对骨缺损修复的实验研究

目的:研究兔下颌骨髁突来源骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMMSCs)的体外分离、培养、鉴定及其体内成骨情况。方法:从兔下颌骨髁突中分离干细胞进行培养,对BMMSCs向成骨、成骨骼肌细胞的分化进行鉴定。实验组将BMMSCs复合于载黄芪多糖(APS)支架材料上,植入骨缺损区;对照组1植入单纯珊瑚羟基磷灰石(CHA)材料;对照组2植入APS/CHA复合材料;空白组不植入任何材料。应用组织学和扫描电镜观察,并比较植入材料与骨组织交界处的成骨修复情况。结果:细胞经过传代后形态一致,呈梭形;ALP染色呈阳性,成骨诱导后形成钙结节;成骨骼肌诱导后desmin免疫细胞化学染色阳性。植入体内修复骨缺损12周,实验组见大量新生骨及活跃的骨细胞;对照组1仅在材料表面见少量新骨形成;对照组2材料内有部分新骨形成;空白组基本未见骨修复。结论:从兔下颌骨髁突中分离、培养出的BMMSCs,具有体内、体外成骨的能力。

Biological Behaviour of Bone Marrow-derived Mesenchymal Stem Cells in Rabbit Mandibular Condyle

Objective: This study aimed to investigate and develop techniques to isolate and expand rabbit mandible condyle/bone-marrow-derived mesenchymal stem cells(BMMSCs) and verify their characteristics,multi-lineage differentiation,and in vivo tissue regeneration.Methods: BMMSCs were isolated from cancellous bone of rabbit condyle and cultured.Filling material to the bone defects were divided into four groups.In experiment group,the rabbit mandible defects were filled with BMMSCs/APS/CHA scaffold.In control group 1,filling material was CHA alone.In control group 2,bone defects were implanted with APS/CHA scaffold.In blank control group,bone defect kept void.At 4,8,and 12 weeks,animals were sacrificed respectively.Histology section and scanning electron microscopy were used to evaluate tissue regeneration.Results: BMMSCs were capable of forming adherent clonogenic cell colonies,single attached cell showing a typical fibroblast-like morphology.BMMSCs showed higher ALP activity.The myogenic potential was demonstrated by positive desmin expression.A huge amount of new bone and active bone cells appeared in the experimental group.In control group 1,only small amount of new bone seen on the surface of material.In control group 2,bone defects were repaired partially.In the blank group,almost no osteogenesis were revealed.Conclusion: Rabbit mandible condyle BMMSCs have the ability of bone formation in vivo and in vitro.