Kirby Giles T S, White Lisa J, Steck Roland, Berner Arne, Bogoevski Kristofor, Qutachi Omar, Jones Brendan, Saifzadeh Siamak, Hutmacher Dietmar W, Shakesheff Kevin M, Woodruff Maria A
Institute of Health and Biomedical Innovation (IHBI), Queensland University of Technology (QUT), Brisban, QLD 4006, Australia.
School of Pharmacy, University Park, The University of Nottingham, University Park, Nottingham NG7 2RD, UK.
Materials (Basel). 2016 Mar 31;9(4):259. doi: 10.3390/ma9040259.
This study trialled the controlled delivery of growth factors within a biodegradable scaffold in a large segmental bone defect model. We hypothesised that co-delivery of vascular endothelial growth factor (VEGF) and platelet derived growth factor (PDGF) followed by bone morphogenetic protein-2 (BMP-2) could be more effective in stimulating bone repair than the delivery of BMP-2 alone. Poly(lactic-co-glycolic acid) (PLGA ) based microparticles were used as a delivery system to achieve a controlled release of growth factors within a medical-grade Polycaprolactone (PCL) scaffold. The scaffolds were assessed in a well-established preclinical ovine tibial segmental defect measuring 3 cm. After six months, mechanical properties and bone tissue regeneration were assessed. Mineralised bone bridging of the defect was enhanced in growth factor treated groups. The inclusion of VEGF and PDGF (with BMP-2) had no significant effect on the amount of bone regeneration at the six-month time point in comparison to BMP-2 alone. However, regions treated with VEGF and PDGF showed increased vascularity. This study demonstrates an effective method for the controlled delivery of therapeutic growth factors , using microparticles.
本研究在一个大段骨缺损模型中，对生长因子在可生物降解支架内的可控递送进行了试验。我们假设，与单独递送骨形态发生蛋白-2（BMP-2）相比，血管内皮生长因子（VEGF）和血小板衍生生长因子（PDGF）联合递送后再递送BMP-2，在刺激骨修复方面可能更有效。基于聚乳酸-乙醇酸共聚物（PLGA）的微粒被用作递送系统，以在医用级聚己内酯（PCL）支架内实现生长因子的控释。在一个成熟的3厘米长的临床前绵羊胫骨节段性缺损模型中对支架进行评估。六个月后，评估力学性能和骨组织再生情况。生长因子治疗组缺损处的矿化骨桥接得到增强。与单独使用BMP-2相比，在六个月时间点时加入VEGF和PDGF（与BMP-2联合）对骨再生量没有显著影响。然而，用VEGF和PDGF处理的区域显示血管增多。本研究证明了一种使用微粒可控递送治疗性生长因子的有效方法。
