Xie Yubing, Yang Yong, Kang Xihai, Li Ruth, Volakis Leonithas I, Zhang Xulang, Lee L James, Kniss Douglas A
College of Nanoscale Science and Engineering, University of Albany, Albany, NY, USA.
Biotechnol Prog. 2009 Mar-Apr;25(2):535-42. doi: 10.1002/btpr.151.
Tissues are composed of multiple cell types in a well-organized three-dimensional (3D) microenvironment. To faithfully mimic the tissue in vivo, tissue-engineered constructs should have well-defined 3D chemical and spatial control over cell behavior to recapitulate developmental processes in tissue- and organ-specific differentiation and morphogenesis. It is a challenge to build a 3D complex from two-dimensional (2D) patterned structures with the presence of cells. In this study, embryonic stem (ES) cells grown on polymeric scaffolds with well-defined microstructure were constructed into a multilayer cell-scaffold complex using low pressure carbon dioxide (CO(2)) and nitrogen (N(2)). The mouse ES cells in the assembled constructs were viable, retained the ES cell-specific gene expression of Oct-4, and maintained the formation of embryoid bodies (EBs). In particular, cell viability was increased from 80% to 90% when CO(2) was replaced with N(2). The compressed gas-assisted bioassembly of stem cell-polymer constructs opens up a new avenue for tissue engineering and cell therapy.
组织由多种细胞类型组成，处于一个组织良好的三维（3D）微环境中。为了忠实地模拟体内组织，组织工程构建体应具备对细胞行为进行明确的3D化学和空间控制，以重现组织和器官特异性分化及形态发生过程中的发育进程。在有细胞存在的情况下，从二维（2D）图案化结构构建3D复合体是一项挑战。在本研究中，利用低压二氧化碳（CO₂）和氮气（N₂），将生长在具有明确微观结构的聚合物支架上的胚胎干细胞（ES细胞）构建成多层细胞-支架复合体。组装构建体中的小鼠ES细胞具有活力，保留了Oct-4的ES细胞特异性基因表达，并维持了胚状体（EB）的形成。特别地，当用N₂替代CO₂时，细胞活力从80%提高到了90%。干细胞-聚合物构建体的压缩气体辅助生物组装为组织工程和细胞治疗开辟了一条新途径。
