三维工程组织的动态模块组装与细胞调控机理研究

Controllable assembly of cell-laden modules is an efficient strategy for thefabrication of 3D engineered tissues (3DET). However, it is the prerequisite forthe development of desired 3DET to overcome the challenge of sustainable andefficient nutrient supplement for the cells during the formation of 3DET and tofind out the mechanism by which the microstructure and assembly interface of modules affect the activity and behaviors of the cells.This project is committed to fabricate 3DET dynamically by utilizing the strategy of module assembly combining with the supermolecular chemistry approach.Briefly, supermolecular assembly systems with controllable “breathing” function are going to be fabricated through reversible host-guest interactions usingchitosan based and cell-laden microgel or aerogel as modules. The dynamic assembly interfaces of modules are helpful for the diffusion and exchange of culture medium, which will accordingly achieve the sustainable and efficient nutrient supplement for the cells during the formation of 3DET. Also importantly, it will explore and disclose the machanism by which the microstructure and dynamic assembly interfaces of cell-laden modules affect the activity and behaviors of the cells, such as the viability, growth, proliferation and differentiation. This project will establish a supermolecular approach to overcome the current challenges in 3DET fabrication such as assembly manners of modules and nutrient supplement, and provide some ideas and direction for individual design of cell-laden modules and their assembly process in the future, laying a solid foundation for the fabrication of desired 3DET which possesses high cell activity, multiple cell types and high cell density.

载细胞模块的可控组装是构建三维工程组织（3DET）的有效策略，而解决在3DET形成过程中细胞的营养供给问题以及深入理解模块的微观结构与组装界面对细胞行为的调控机制是构建理想3DET的前提。本项目拟采用模块组装策略、借助超分子化学手段动态构建3DET，即以负载细胞的壳聚糖基微凝胶或气凝胶颗粒为模块，通过可逆的主客体相互作用动态构建具有可控“呼吸”功能的载细胞模块的超分子组装体系。模块的动态组装界面有利于培养液的扩散与交换，从而实现在3DET形成过程中持续有效的营养供给；通过调节模块的微观结构与动态组装过程，探明载细胞模块的微观结构与模块组装界面对细胞存活、生长、增殖与分化的影响及调控机理。本项目将为3DET构建的模块组装方式以及营养供给问题提供超分子化学的解决途径，并为未来个性化设计载细胞模块及其组装过程提供思路和方向，为最终构建具有高细胞活力、多细胞种类与高细胞密度的3DET奠定基础。

本项目旨在建立基于超分子模块组装策略构建三维工程组织的方法，并阐明模块组装过程中细胞调控机理。在具体实施过程中，本项目首先通过制备具有合适结构与功能的多孔微球构建了载细胞微模块，研究了载细胞微模块的本体性质与微观结构对细胞黏附、增殖、迁移、分化等行为的影响。其次通过一系列超分子水凝胶体系的构建探究了载细胞模块的超分子动态组装策略。最后以载细胞微模块为组装单元，采用声场驱动模块组装的策略构建了图案化三维工程组织，并深入研究了模块组装过程中细胞调控与组织形成的机理。载细胞多孔微球可为细胞提供三维生长环境，有利于维持细胞形态和功能，结合非接触式、非侵入式的声场驱动组装方式，很好地解决了工程化构建过程中对细胞活性的损伤问题，获得了高活性三维工程组织，为三维工程组织的构建提供了新的思路。本项目较好地完成了既定研究目标，并超额完成了在论文发表、专利申请和人才培养等研究成果方面的预定目标。