图形化三维水凝胶基质应用于微血管组织构建的基础研究

项目名称： 图形化三维水凝胶基质应用于微血管组织构建的基础研究

项目编号： No.30800216

项目类型： 青年科学基金项目

立项/批准年度： 2009

项目学科： 生物科学

项目作者： 罗莹

作者单位： 北京大学

项目金额： 23万元

中文摘要： 图形化技术通过在材料基底加工生物化学或拓补形貌的有序图案，对细胞的空间形状、取向及组织形态实施调控。生物材料的图形化技术在现代细胞生物学和组织工程学研究中已经成为一种重要的加工细胞基底的方法。本项目重点研究了通过一种微塑形技术，在可降解的三维水凝胶基底加工出形貌结构，用以引导血管细胞的自组装和生长。利用经混合原位成形的透明质酸-葡聚糖复合水凝胶为模型材料，加工了出底部为胶原粘附区域、尺度可控（30-200 微米）的规整微槽图形。该基底对血管内皮细胞显示了高度的引导性能，而图形的几何特征则决定细胞的空间聚集方式和微血管生成过程。同时发现成纤维细胞可以与内皮细胞复合，形成能模拟血管发生机制的三维共培养系统。该体系将为体外研究血管发生、细胞与干细胞三维培养等工作提供极为便捷而实用的技术，有望推动相关领域的发展。我们还将水凝胶图形化技术应用于不可生物降解水凝胶，通过加工微槽图形引导细胞团在三明治系统中的定位。这种技术能使例如胰岛、微肝等组织封闭于水凝胶材料，为免疫隔离装置的设计开辟了一种全新的思路和方法，在干细胞移植中有着重要的应用前景。

中文关键词： 水凝胶；图形化；微血管；引导；内皮细胞

英文摘要： Investigating strategies to generate guidance cues in biomaterials to modulate the multicellular organization for promoting tissue morphogenesis has important implications for tissue engineering and regenerative medicine. We here demonstrate a facile approach to create structural patterns on biodegradable hydrogel matrices via a micromolding process to enable three-dimensional assembly and vessel morphogenesis of endothelial cells. Human umbilical cord vein endothelial cells (HUVECs), with or without stromal fibroblasts were cultured on hydrogel matrices made of hyaluronic acid and dextran containing microgrooves of different widths. It is found that by appropriately manipulating the microgroove geometry, the patterned matrices can support endothelial cells to assemble into microvessel-like structures in mono- and co-culture configurations. The study provides a basic model for investigating and engineering the microvessel tissue component for building vascularized tissue constructs. Taking advanatge of the micromolding technique, we also devised a method to create sandwiched cell arrays between hydrogel membranes. Speriod arregates were found able to automatically located in the microwell region patterned on the hydrogel matrices. The sandwich configuration would find important applications in cell/tissue transplantation, and in particular would establish a new way to faricate immunoisolation devices for use in safe transplantation of stem cell-derived tissues such as islets.

英文关键词： hydrogel; patterning; microvessel; guided; endothelial celll