Shin Michael, Matsuda Kant, Ishii Osamu, Terai Hidetomi, Kaazempur-Mofrad Mohammed, Borenstein Jeffrey, Detmar Michael, Vacanti Joseph P
Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.
Biomed Microdevices. 2004 Dec;6(4):269-78. doi: 10.1023/B:BMMD.0000048559.29932.27.
One key challenge in regenerating vital organs is the survival of transplanted cells. To meet their metabolic requirements, transport by diffusion is insufficient, and a convective pathway, i.e., a vasculature, is required. Our laboratory pioneered the concept of engineering a vasculature using microfabrication in silicon and Pyrex. Here we report the extension of this concept and the development of a methodology to create an endothelialized network with a vascular geometry in a biocompatible polymer, poly(dimethyl siloxane) (PDMS). High-resolution PDMS templates were produced by replica-molding from micromachined silicon wafers. Closed channels were formed by bonding the patterned PDMS templates to flat PDMS sheets using an oxygen plasma. Human microvascular endothelial cells (HMEC-1) were cultured for 2 weeks in PDMS networks under dynamic flow. The HMEC-1 cells proliferated well in these confined geometries (channel widths ranging from 35 mum to 5 mm) and became confluent after four days. The HMEC-1 cells lined the channels as a monolayer and expressed markers for CD31 and von Willebrand factor (vWF). These results demonstrate that endothelial cells can be cultured in confined geometries, which is an important step towards developing an in vitro vasculature for tissue-engineered organs.
再生重要器官的一个关键挑战是移植细胞的存活。为了满足其代谢需求，通过扩散进行的物质运输是不够的，还需要一个对流途径，即脉管系统。我们实验室率先提出了利用硅和派热克斯玻璃中的微加工技术构建脉管系统的概念。在此，我们报告了这一概念的扩展以及一种方法的开发，该方法可在生物相容性聚合物聚二甲基硅氧烷（PDMS）中创建具有血管几何形状的内皮化网络。通过从微加工硅晶片进行复制模塑来制作高分辨率的PDMS模板。使用氧等离子体将图案化的PDMS模板与平坦的PDMS片材键合形成封闭通道。人微血管内皮细胞（HMEC-1）在动态流动下于PDMS网络中培养2周。HMEC-1细胞在这些受限的几何形状（通道宽度范围从35微米到5毫米）中增殖良好，并在四天后汇合。HMEC-1细胞作为单层排列在通道内，并表达CD31和血管性血友病因子（vWF）的标志物。这些结果表明内皮细胞可以在受限的几何形状中培养，这是朝着为组织工程器官开发体外脉管系统迈出的重要一步。
