Department of Mechanical Engineering, Stanford University, Stanford, CA 94305, USA.
Proc Natl Acad Sci U S A. 2010 Nov 30;107(48):20709-14. doi: 10.1073/pnas.1005211107. Epub 2010 Nov 11.
Cell encapsulating poly(ethylene glycol) hydrogels represent a promising approach for constructing 3D cultures designed to more closely approximate in vivo tissue environment. Improved strategies are needed, however, to optimally balance hydrogel permeability to support metabolic activities of encapsulated cells, while maintaining patternability to restore key aspects of tissue architecture. Herein, we have developed one such strategy incorporating hydrophobic nanoparticles to partially induce looser cross-linking density at the particle-hydrogel interface. Strikingly, our network design significantly increased hydrogel permeability, while only minimally affecting the matrix mechanical strength or prepolymer viscosity. This structural advantage improved viability and functions of encapsulated cells and permitted micron-scale structures to control over spatial distribution of incorporated cells. We expect that this design strategy holds promise for the development of more advanced artificial tissues that can promote high levels of cell metabolic activity and recapitulate key architectural features.
细胞包封聚乙二醇水凝胶代表了构建更接近体内组织环境的 3D 培养物的一种很有前途的方法。然而，需要改进策略，以最佳地平衡水凝胶的渗透性，以支持被包裹细胞的代谢活动，同时保持可成型性以恢复组织结构的关键方面。在这里，我们开发了一种策略，即将疏水性纳米颗粒整合到水凝胶中，以部分诱导颗粒-水凝胶界面处更疏松的交联密度。引人注目的是，我们的网络设计显著提高了水凝胶的渗透性，而对基质力学强度或预聚物粘度的影响最小。这种结构优势提高了被包裹细胞的活力和功能，并允许微米级结构控制掺入细胞的空间分布。我们预计，这种设计策略有望开发出更先进的人工组织，这些组织可以促进高水平的细胞代谢活动，并再现关键的结构特征。
