Institute for Biological Interfaces, Karlsruhe Institute of Technology, Campus North, P.O. Box 3640, 76021 Karlsruhe, Germany.
Biomed Microdevices. 2012 Apr;14(2):291-301. doi: 10.1007/s10544-011-9605-8.
Since three-dimensional (3D) cell culture models better reflect tissues in vivo in terms of cell shape and microenvironment compared to conventional monolayer cultures, 3D tissue culture substrates gain more importance for a wide range of biological applications like drug discovery, toxicological studies, cancer and stem cell research. In this study we developed a method for the fabrication of 3D cell culture substrates in a multiwell plate format by microstructuring the bottom of 96-well cell culture plates using an ultrasonic embossing process. The resulting microstructured area consists of cubic microcavities in which adherent multicellular aggregates can be formed. We performed the biological evaluation of the system with the liver-derived human cell-line HepG2 and compared the novel substrate with a commercially available 3D culture system comprising porous alginate sponges. Metabolic activity (alamarBlue® reduction) and induction of four biotransformation enzymes (EROD, ECOD, UGT, SULT) were determined by fluorimetry or HPLC. Our results revealed that HepG2 cells in microstructured plates showed a higher mitochondrial activity, as well as enzyme activity of ECOD and UGT after treatment with an inducer when compared to cells cultured in alginate sponges at otherwise comparable conditions. Since we have modified standard cell culture plates, the obtained system is adaptable to automated screening and might be useful for all kinds of cultures including adult, progenitor and stem cells which need a 3D culture configuration to restore or maintain the differentiated status.
由于三维（3D）细胞培养模型在细胞形状和微环境方面比传统的单层培养更能反映体内组织，因此 3D 组织培养基质在药物发现、毒理学研究、癌症和干细胞研究等广泛的生物学应用中变得更加重要。在这项研究中，我们开发了一种在 96 孔细胞培养板格式中制造 3D 细胞培养基质的方法，通过使用超声压印工艺对 96 孔细胞培养板的底部进行微结构处理。所得的微结构区域由立方微腔组成，其中可以形成贴壁的多细胞聚集体。我们用肝源性人细胞系 HepG2 对该系统进行了生物学评估，并将新型基质与一种商业上可用的包含多孔海藻酸盐海绵的 3D 培养系统进行了比较。通过荧光法或 HPLC 测定代谢活性（alamarBlue®还原）和四种生物转化酶（EROD、ECOD、UGT、SULT）的诱导。我们的结果表明，与在海藻酸盐海绵中培养的细胞相比，在微结构板中培养的 HepG2 细胞在诱导物处理后具有更高的线粒体活性以及 ECOD 和 UGT 的酶活性。由于我们已经对标准细胞培养板进行了修改，因此获得的系统可适用于自动化筛选，并且可能对包括成体、祖细胞和干细胞在内的各种培养物都有用，这些细胞需要 3D 培养结构来恢复或维持分化状态。
