Acceleration of distraction osteogenesis with recombinant human bone morphogenetic protein-2 transfected into normal mesenchymal cell.

制备了编码绿色荧光素蛋白与重组人骨形态发生蛋白-2（rhBMP-2）融合蛋白的质粒载体，用脂质体法转染小鼠成纤维细胞系C2 C12和NIH 3 T3，发现rhBMP-2的mRNA表达增加，激光扫描显微镜下可见GFP表达，免疫组化结果显示，转染GFP-rhBMP-2的C2 C12细胞ALP活性明显升高，I型胶原和转染的大鼠骨髓基质细胞的ALP活性明显升高，移植于大鼠肱二头肌股骨头及外固定器造成的5 mm股骨缺损处，放射性造影显示无骨形成，种植园后，将编码GFP-rhBMP-2的基因导入股骨干，每天延长0.5mm，共10天，结果相同。2转染正常骨髓间充质细胞，经免疫组化检测未见融合蛋白表达增加，转染细胞在体外培养条件下ALP活性略有增加，但未见异位成骨或骨形成加速，需要改变GFP-rhBM-2基因的结构，或将载体从质粒转换为病毒。

We made the plasmid vector coding fusion protein of green fluorescein protein and recombinant human bone morphogenetic protein-2(rhBMP-2).The plasmid vector were transfected into C2C12, and NIH3T3, fibroblast cell line of mouse with lipofection.Expression of mRNA of rhBMP-2 were increased.Transfected cells showed GFP expression with laser scanning microscopy, but no relation between expression of rhBMP-2 and GFP with immunohistological study.C2C12 cells transfected with GFP-rhBMP-2 shows increasing of ALP activity.Type I collagen and transfectd bone marrow stromal cells harvested from rat's femur, were transplantation into rat biceps femorins and 5mmfemoral bone defect made with external fixators.Rhoentogenographic study showed no bone formation.After plantation of transfected cells and collagen, lengthening of femur were done 0.5mm per day for 10days.The results were the same.Gene coding GFP-rhBMP-2 were transfected into normal mesenchymal cells, but did not show increaeing of production of fusion protein with immunohistochemically.Transfected cellsshowed slight increase of ALP activity under in vivocircumference, but dose not showed heterotopic bone formation or acceleration of bone formation.It needed to change the construction of GFP-rhBM-2 gene, or to swich the vector from plasmid to virus.