Department of Mechanical Engineering, University of Louisville, Louisville, KY 40292, USA.
Biomaterials. 2011 Mar;32(7):1872-9. doi: 10.1016/j.biomaterials.2010.11.023. Epub 2010 Dec 8.
The engineering of large (thickness > 100 μm) tissues requires a microvascular network to supply nutrients and remove waste. To produce microvasculature in vitro, a scaffold is required to mechanically support and stimulate endothelial cell (EC) adhesion and growth. Scaffolds for ECs are currently produced by patterning polymers or other biomaterials into configurations which often possess isotropic morphologies such as porous films and fibrous mats. We propose a new "direct-write" process for fabricating scaffolds composed of suspended polymer microfibers that are precisely oriented in 3D, providing directional architecture for selectively guiding cell growth along a desired pathway. The diameters of the fibers produced with this process were predictably and repeatably controlled through modulation of the system parameters, enabling production of fibers with microvascular-scale diameters (5-20 μm) from a variety of biodegradable polymers. These scaffolds were successfully seeded with ECs, which conformed to the geometry of the fibers and proliferated over the course of one week.
制造大厚度（> 100 μm）组织需要一个微血管网络来供应营养物质和清除废物。为了在体外产生微血管，需要支架来机械支撑和刺激内皮细胞（EC）的黏附和生长。目前，用于 EC 的支架是通过将聚合物或其他生物材料图案化制成具有各向同性形态的结构来生产的，例如多孔膜和纤维垫。我们提出了一种新的“直接写入”工艺，用于制造由悬浮聚合物微纤维组成的支架，这些纤维在 3D 中精确定向，为选择性地沿着所需路径引导细胞生长提供了定向结构。通过调节系统参数，可以可预测且可重复地控制该工艺产生的纤维直径，从而可以从各种可生物降解的聚合物中生产出具有微血管尺度直径（5-20 μm）的纤维。这些支架成功地接种了 EC，它们顺应纤维的几何形状，并在一周的时间内增殖。
