Establishment of the premises for using the pro-form of bone morphogenetic protein (BMP-2) as a therapeutic tool

骨形态发生蛋白(BMP-2)自2002年开始临床应用。临床适应证主要为缓慢愈合的骨折。最近，有报道称BMP-2的应用伴随着不良反应。由于在我们的研究中，BMP-2的剂量明显低于临床应用的剂量，诱导了异位骨形成，副作用可能是由于剂量调整不足所致。对于与转化生长因子相关的转化生长因子，已经证实了前肽的潜伏期赋予作用。我们自己的数据间接表明，BMP-2的前肽可能会延缓成熟生长因子的活性。因此，ProBMP-2可能是一种迟效的治疗性蛋白，其过量效应可能被前肽内在地抵消。该提案的目的是测试ProBMP-2作为一种新型的、延缓作用的骨再生药物的给药前提。以下副主题将涉及：重组生产和复性真实的proBMP-2，分析载体材料(用于体内给药)和自旋标记(用于体内监测)对蛋白质结构和功能的影响，从载体材料中释放生长因子的测定，以及proBMP-2引起的生物反应的测定。

Bone morphogenetic protein (BMP-2) is in clinical use since 2002. Clinical indications are mainly slow healing fractures. Recently, the administration of BMP-2 has been reported to be accompanied by adverse side effects. Since in our studies significantly lower doses of BMP-2 than those applied in the clinic had induced ectopic bone formation, the side effects may be due to insufficient doses adjustment. For the related transforming growth factor-ß (TGF-ß), a latency conferring role of the pro-peptide has been demonstrated. Our own data indirectly suggest that the pro-peptide of BMP-2 may retard the activity of the mature growth factor. Thus, proBMP-2 may be a late acting therapeutic protein by which overdoses effects may be intrinsically counteracted by the pro-peptide. The objective of the proposal is testing the premises for administration of proBMP-2 as a novel, delayed acting drug for bone regeneration. The following subtopics will be dealt with: Optimization of recombinant production and refolding of authentic proBMP-2, analysis of the effect of carrier materials (for in vivo delivery) and spin labels (for in vivo monitoring) on structure and function of the protein, determination of growth factor release from the carrier material and determination of the biological responses elicited by proBMP-2.