Bone regeneration by BMP2-gene transduced mesenchymal stem cells.

该项目的目标是通过在骨髓中自体移植来源于间充质干细胞的成骨细胞来再生骨。(1)转BMP2基因的骨髓间充质干细胞的骨再生构建了含人BMP2基因的重组逆转录病毒载体。通过逆转录病毒介导的BMP2基因转导，将原代培养的大鼠骨髓间充质干细胞分化为成骨细胞。组织学分析表明，BMP2转导的骨髓干细胞接种于羟基磷灰石上可在体内形成新的骨形成。(2)新型骨再生支架制备了一种含羟基磷灰石颗粒的可水解聚轮烷交联的聚乙二醇水凝胶(PRX-HAP)。成骨细胞在PRX-HAP表面附着并存活。组织学分析显示，在PRX-HAPS与成骨样细胞队列之间的区域可见类骨样组织。PRX-HAPS在骨组织工程中具有巨大的潜力。(3)人骨髓基质细胞在患者自体血清中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能够支持其骨髓基质细胞的生长和分化。患者的自体血清可以在不丧失其向成骨细胞分化的潜能的情况下扩增BMSCs。患者自体血清可有效扩增骨髓间充质干细胞，安全地用于骨再生治疗。

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.