骨髓基质干细胞联合血管束植入构筑血管化组织工程骨

Bone marrow stromal cells combined with vascular bundle implants in porous xenogeneic deproteinised cancellous bone to construct vascularized bone

目的研究兔骨髓基质干细胞（bonemarrowstromalcells，BMSCs）联合动静脉血管束植入异种脱蛋白松质骨（xenogeneicdeproteinisedcancellousbone，XDCB）构筑血管化组织工程骨，为构建组织工程化骨提供新的思路。方法从兔髂嵴抽骨髓培养制备兔BMSCs，将第3代BMSCs种植于多孔XDCB并进行成骨诱导2周。手术中分离兔隐动、静脉血管束（vascularbundle，VB），以备穿过有孔的XDCB中。取24只新西兰大白兔，其中12只游离双侧兔隐动静脉血管束，共24侧；另外12只兔仅切开股骨外皮肤植入异种骨，共24侧。实验分4组（n=12），A组为单纯材料植入皮下组（XDCB组），B组为干细胞植入材料组（XDCB＋BMSCs组），C组为血管束植入材料组（XDCB＋VB组），D组为干细胞＋血管束植入材料组（Ⅺ）CB＋BMSCs＋VB组），各组交叉配对。分别于术后2、4、8周行大体解剖、碱性磷酸酶（J岫）活性检测、茜素红（ARS）染色、组织切片等检查，观察各组移植物血管化情况。结果D组血管化组织工程骨组可见到血管新生、部分新生骨情况优于B组，也优于C组，而A组的异种骨中未测及相应血管化及成骨效能。结论BMSCs联合动静脉血管束植入XDCB构筑的血管化组织工程骨有一定的成骨效能，并且可见到材料内部血管化，为构建组织工程化骨提供了新的思路。

Objective To study the feasibility of vascularized bone constructed by bone marrow stromal cells （BMSCs）combined with vascular bundle implants in porous xenogeneic deproteinised cancellous bone （XDCB）. Methods BMSCs were prepared from bone marrow extracted from rabbit iliac crest. The third passage BMSCs were transplanted to XDCB for 2 weeks of osteogenesis. The 48 hind limbs of 24 New Zealand white rabbits were randomized into 4 groups （ n = 12）. In Group A XDCB was implanted into a subcutaneous pouch of the thigh （XDCB group）. In group B XDCB enriched with BMSCs was implanted subcutaneously （XDCB ＋ BMSCs group）. In group C the saphenous artery and vein vascular bundle was carefully harvested and channeled into the XDCB which was implanted subcutaneously （XDCB ＋ VB group）. In group D both BMSCs and vascular bundle were introduced into XDCB that was implanted （XDCB ＋ BMSCs ＋ VB group）. After 2, 4 and 8 weeks, the implants were harvested. Gross anatomic observation, alkaline phosphatase （ALP） activity, alizarin red S （ARS） staining and H＆E staining of tissue slices of the implants were carried out. Results Bone formations could be found in samples of all the groups except group A. Group D showed more robust angiogenesis and new bone-formation comparing to those of group B and C. No vascularization was observed in samples from group A. Conclusion Vascularized bone constructed by BMSCs combined with vascular bundle implants in porous XDCB can accelerate the vascularization and osteogenesis process of the implant. This approach provides a new idea for building tissue-engineered bone.