Development of a therapeutic method of bone repair using BMP responding mesencbymal cells

1971年，Urist将从脱矿骨基质中提取的具有异位骨形成活性的蛋白质命名为骨形态发生蛋白(BMP)。这表明，骨祖细胞可以在BMP的响应下分化为成骨细胞，存在于肌肉和皮下组织中。人骨形成蛋白cDNAs于1988年首次被克隆，目前已有超过15个编码BMPs的cDNAs被克隆。最近，骨形态发生蛋白受体也被克隆出来。我们研究了BMP-2在骨骼间充质细胞分化调控中的作用。在本研究中，我们进行了多项实验，以探索一种新的骨修复治疗方法，获得了以下结果：1)通过原位杂交和免疫组织化学方法证实了BMP-2受体(IA、IB和II)在原代大鼠成骨细胞中的表达。2)我们利用不同的培养细胞观察了BMP-2对成骨细胞分化的影响，并证明了BMP-2对不同细胞类型的作用不同。3)我们开始证明BMP-2诱导成骨细胞在人肌肉和皮肤成纤维细胞中分化。4)我们将BMP-2IPGS与成骨前体细胞复合后移植到骨缺损中。这种方法比单纯移植BMP-2IPGS更有效地生成新骨。5)我们制备了针对BMP受体IA的抗体，但未能获得中和抗体。

In 1971, Urist gave name bone morphogenetic protein (BMP) for the protein which was extracted from demineralized bone matrix with bloactivity inducing ectopic bone formation. This indicates that osteoprogenitor cells, which can differentiate into osteoblasts in response to BMP, are present in muscle and subcutaneous tissue. Human BMP cDNAs were first cloned in 1988, and over 15 cDNAs encoding BMPs have been cloned at present. Recently BMP receptors have also cloned. We have investigated the role of BMP-2 in regulation of differentiation of skeletal mesenchymal cells. In the present study, we conducted several experiments to develop a novel therapeutic method of bone repair, and obtained the following results.1) We confirmed the expression of BMP receptors (IA, IB and II) in primary rat osteoblastic cells by in situ hybridization and immunohistochemistry.2) We investigated the effect of BMP-2 on osteoblast differentiation using various culture cells, and demonstrated that the effects of BMP-2 varied among cell types used.3) We demonstarted that BMP-2 induced osteoblast differentiation in human muscles and skin fibroblasts.4) We transplanted BMP-2IPGS complex with osteoprogenitor cells into bone defects. This method generated new bone more effectively than that simply transplanted BMP-2IPGS.5) We triad to make antibodies against BMP receptor IA, but could not obtain neutralizing antibodies.