Department of Bioengineering, University of Washington, Seattle, Washington 98195, USA.
J Biomed Mater Res A. 2012 Jun;100(6):1605-14. doi: 10.1002/jbm.a.34102. Epub 2012 Mar 23.
The fabrication of biomimetic scaffolds is a critical component to fulfill the promise of functional tissue-engineered materials. We describe herein a simple technique, based on printed circuit board manufacturing, to produce novel templates for electrospinning scaffolds for tissue-engineering applications. This technique facilitates fabrication of electrospun scaffolds with templated architecture, which we defined as a scaffold's bulk mechanical properties being driven by its fiber architecture. Electrospun scaffolds with templated architectures were characterized with regard to fiber alignment and mechanical properties. Fast Fourier transform analysis revealed a high degree of fiber alignment along the conducting traces of the templates. Mechanical testing showed that scaffolds demonstrated tunable mechanical properties as a function of templated architecture. Fibroblast-seeded scaffolds were subjected to a peak strain of 3 or 10% at 0.5 Hz for 1 h. Exposing seeded scaffolds to the low strain magnitude (3%) significantly increased collagen I gene expression compared to the high strain magnitude (10%) in a scaffold architecture-dependent manner. These experiments indicate that scaffolds with templated architectures can be produced, and modulation of gene expression is possible with templated architectures. This technology holds promise for the long-term goal of creating tissue-engineered replacements with the biomechanical and biochemical make-up of native tissues.
仿生支架的制造是实现功能性组织工程材料的关键组成部分。我们在此描述了一种基于印刷电路板制造的简单技术,用于为组织工程应用的电纺支架生产新型模板。该技术便于制造具有模板结构的电纺支架,我们将其定义为支架的整体机械性能由其纤维结构驱动。对具有模板结构的电纺支架的纤维排列和机械性能进行了表征。快速傅里叶变换分析显示,纤维沿着模板的导电迹线高度取向。机械测试表明,支架的机械性能可以作为模板结构的函数进行调节。将纤维原代细胞接种到支架中,在 0.5 Hz 下以 3%或 10%的峰值应变进行 1 小时的拉伸。与高应变幅度(10%)相比,以支架结构依赖性的方式将接种支架暴露于低应变幅度(3%)下可显著增加胶原蛋白 I 基因的表达。这些实验表明,具有模板结构的支架可以被制造出来,并且可以通过模板结构来调节基因表达。该技术有望实现长期目标,即用具有生物力学和生物化学特性的组织工程替代物来替代天然组织。