Wildemann B, Lübberstedt M, Haas N P, Raschke M, Schmidmaier G
Department of Trauma and Reconstructive Surgery, Charité-Campus Virchow, Humboldt-University of Berlin, Augustenburger Platz 1, Berlin 13353, Germany.
Biomaterials. 2004 Aug;25(17):3639-44. doi: 10.1016/j.biomaterials.2003.10.058.
Biodegradable coating of osteosynthetic materials with poly(D,L-lactide) (PDLLA) and incorporated growth factors has been used successfully as drug carrier to stimulate fracture healing in several rat and porcine models. A cold coating technique was used to incorporate growth factors without loss of activity during the coating process. The aim of this study was to investigate the activity of incorporated insulin like growth factor-I and transforming growth factor-beta 1 (TGF-beta1) after long-time storage (5 and 14 months at -20 degrees C). Primary human osteoblast-like cells (HOB) were cultured in a non-contact manner with titanium wires coated with PDLLA and IGF-I (33 microg) and TGF-beta1 (6 microg) for 0, 5, 10 and 15 days. Osteoblast culture without wires, with titanium wires or wires with the PDLLA coating served as control ( n=3 each time point and group). Cell vitality, cell proliferation and the production of procollagen 1 were measured. No differences in cell count and vitality were accessed in the two growth factor treated groups compared to the control groups at the same time point. Independently from the storage duration, the incorporated growth factors significantly stimulated the production of osteoblast specific type I collagen (CICP) compared to the controls. The results indicate, that the growth factors stimulated osteoblast to an enhanced collagen 1 production and that the coating method meets a major requirement for clinical use of growth factor-coated implants: biological activity of the incorporated growth factors for at least 14 months.
聚（D，L-丙交酯）（PDLLA）及掺入生长因子的骨合成材料可生物降解涂层，已成功用作药物载体，在多个大鼠和猪模型中促进骨折愈合。采用冷涂层技术在涂层过程中掺入生长因子且不损失其活性。本研究的目的是调查长时间储存（-20℃下5个月和14个月）后掺入的胰岛素样生长因子-I和转化生长因子-β1（TGF-β1）的活性。将原代人成骨样细胞（HOB）以非接触方式与涂有PDLLA以及IGF-I（33微克）和TGF-β1（6微克）的钛丝培养0、5、10和15天。不使用钛丝、仅使用钛丝或使用涂有PDLLA涂层的钛丝进行成骨细胞培养作为对照（每个时间点和每组n = 3）。测量细胞活力、细胞增殖和前胶原1的产生。与相同时间点的对照组相比，两个生长因子处理组在细胞计数和活力方面没有差异。与对照组相比，无论储存时间长短，掺入的生长因子均显著刺激成骨细胞特异性I型胶原蛋白（CICP）的产生。结果表明，生长因子刺激成骨细胞增加胶原蛋白1的产生，并且该涂层方法满足生长因子涂层植入物临床应用的一项主要要求：掺入的生长因子的生物活性至少持续14个月。
