Reyes Catherine D, Petrie Timothy A, Burns Kellie L, Schwartz Zvi, García Andrés J
Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA.
Biomaterials. 2007 Jul;28(21):3228-35. doi: 10.1016/j.biomaterials.2007.04.003. Epub 2007 Apr 5.
Implant osseointegration is a prerequisite for clinical success in orthopaedic and dental applications, many of which are restricted by loosening. Biomaterial surface modification approaches, including calcium-phosphate ceramic coatings and macro/microporosity, have had limited success in promoting integration. To improve osseointegration, titanium surfaces were coated with the glycine-phenylalanine-hydroxyproline-glycine-glutamate-arginine (GFOGER) collagen-mimetic peptide, selectively promoting alpha2beta1 integrin binding, a crucial event for osteoblastic differentiation. Titanium surfaces presenting GFOGER triggered osteoblastic differentiation and mineral deposition in bone marrow stromal cells, leading to enhanced osteoblastic function compared to unmodified titanium. Furthermore, this integrin-targeted coating significantly improved in vivo peri-implant bone regeneration and osseointegration, as characterized by bone-implant contact and mechanical fixation, compared to untreated titanium in a rat cortical bone-implant model. GFOGER-modified implants also significantly enhanced osseointegration compared to surfaces modified with full-length type I collagen, highlighting the importance of presenting specific biofunctional domains within the native ligand. In addition, this biomimetic implant coating is generated using a simple, single-step procedure that readily translates to a clinical environment with minimal processing and cytotoxicity concerns. Therefore, this study establishes a biologically active and clinically relevant implant-coating strategy that enhances bone repair and orthopaedic implant integration.
种植体骨整合是骨科和牙科应用临床成功的先决条件，其中许多应用都受到松动的限制。生物材料表面改性方法，包括磷酸钙陶瓷涂层和宏观/微观孔隙率，在促进整合方面取得的成功有限。为了改善骨整合，在钛表面涂覆了甘氨酸-苯丙氨酸-羟脯氨酸-甘氨酸-谷氨酸-精氨酸（GFOGER）胶原模拟肽，选择性促进α2β1整合素结合，这是成骨细胞分化的关键事件。呈现GFOGER的钛表面触发了骨髓基质细胞中的成骨细胞分化和矿物质沉积，与未改性的钛相比，导致成骨细胞功能增强。此外，在大鼠皮质骨-种植体模型中，与未处理的钛相比，这种靶向整合素的涂层显著改善了体内种植体周围的骨再生和骨整合，其特征为骨-种植体接触和机械固定。与用全长I型胶原改性的表面相比，GFOGER改性的种植体也显著增强了骨整合，突出了在天然配体中呈现特定生物功能域的重要性。此外，这种仿生种植体涂层是通过简单的单步程序生成的，很容易转化为临床环境，且对加工和细胞毒性的担忧最小。因此，本研究建立了一种具有生物活性且与临床相关的种植体涂层策略，可增强骨修复和骨科种植体整合。
