Bone regeneration by BMP2-gene transduced mesenchymal stem cells.

本课题的研究目的是通过自体骨髓间充质干细胞来源的成骨细胞移植来实现骨再生。我们进行了如下研究。（1）BMP-2基因转染骨髓间充质干细胞的骨再生研究逆转录病毒介导BMP 2基因转染原代培养的大鼠骨髓间充质干细胞，使其向成骨细胞分化。组织学分析显示，BMP 2转导的骨髓干细胞接种在羟基磷灰石上后，体内可形成新骨。（2）新型骨再生支架我们制备了一种由可水解的含羟基磷灰石颗粒的聚轮烷交联的聚乙二醇（PEG）水凝胶（PRX-HAp）。观察到成骨细胞在PRX-HAp表面附着并存活。组织学分析显示，在PRX-HAps和成骨细胞样细胞队列之间的区域观察到类骨质组织。PRX-HAps在骨组织工程中具有巨大的应用潜力。（3）自体血清对人骨髓基质细胞的扩增为了克服牛血清的风险，我们检测了患者的自体血清是否可以支持他/她的骨髓基质细胞（BMSCs）的生长和分化。患者的自体血清可以扩增BMSCs而不丧失其成骨分化的潜力。患者自体血清可有效扩增骨髓间充质干细胞，并可安全用于骨再生治疗。

The goals of this project is regeneration of bone by autotransplantation of osteoblastic cells derived from mesenchymal stem cells in bone marrow. We have performed studies as follows.(1)Bone regeneration by BMP2-gene transduced mesenchymal stem cellsWe generated recombinant retrovirus vector including human BMP2 cDNA. Primary cultured rat mesenchymal stem cells were differentiated into osteoblasts by retrovirus mediated gene transduction of BMP2. Histological analysis showed that the newly bone formation in vivo by transplantation of BMP2-transduced bone marrow stem cells seeded on hydroxyapatite.(2)Novel scaffold for bone regenerationWe produced a poly (ethylene glycol)(PEG) hydrogel cross-linked by a hydrolyzable polyrotaxane containing hydroxyapatite particles (PRX-HAp). Osteoblasts were observed to attach and survive on the surface of PRX-HAp. Histological analysis showed that osteoid-like tissues were seen in the region between PRX-HAps and a queue of osteoblast-like cells. The PRX-HAps have the great potential for bone tissue engineering.(3)Expansion of human bone marrow stromal cells with patient's autologus serumTo overcome the risk of bovine serum, we examined whether a patient's autologous serum could support the growth and differentiation of his/her bone marrow stromal cells (BMSCs). A patient's autologous serum could expand BMSCs without losing their potentiality for osteoblastic differentiation. Patients' autologous serum could be efficient to expand BMSCs and to be utilized safely for bone regeneration therapy.