State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering , Xi'an Jiaotong University , Xi'an , Shaanxi 710049 , People's Republic of China.
Bioinspired Engineering & Biomechanics Center (BEBC) , Xi'an Jiaotong University , Xi'an , Shaanxi 710049 , P. R. China.
ACS Appl Mater Interfaces. 2018 Apr 18;10(15):12374-12389. doi: 10.1021/acsami.7b17751. Epub 2018 Apr 5.
In vivo, cells are located in a dynamic, three-dimensional (3D) cell microenvironment, and various biomaterials have been used to engineer 3D cell microenvironments in vitro to study the effects of the cell microenvironment on the regulation of cell fate. However, conventional hydrogels can only mimic the static cell microenvironment without any synchronous regulations. Therefore, novel hydrogels that are capable of responding to specific stimuli (e.g., light, temperature, pH, and magnetic and electrical stimulations) have emerged as versatile platforms to precisely mimic the dynamic native 3D cell microenvironment. Among these novel hydrogels, photoresponsive hydrogels (PRHs) that are capable of changing their physical and chemical properties after exposure to light irradiation enable the dynamic, native cell microenvironment to be mimicked and show great promise in deciphering the unknown mechanisms of the 3D cell microenvironment in regulating the cell fate. Several reviews have already summarized the advances of PRHs and have focused on specific photosensitive chemical groups and photoresponsive elements or on the reaction categories and mechanism of PRHs. However, a holistic view of novel PRHs, which highlights the multiple physical and chemical properties that can be tuned by remote light activation, as well as their applications in engineering a dynamic cell microenvironment for the regulation of cell behaviors in vitro is still missing and is the focus of this review.
在体内，细胞位于动态的三维 (3D) 细胞微环境中，各种生物材料已被用于体外工程 3D 细胞微环境，以研究细胞微环境对细胞命运调控的影响。然而，传统的水凝胶只能模拟静态的细胞微环境，而没有任何同步的调节。因此，能够响应特定刺激（例如光、温度、pH 值以及磁和电刺激）的新型水凝胶作为多功能平台出现，能够精确模拟动态天然 3D 细胞微环境。在这些新型水凝胶中，光响应水凝胶 (PRH) 在暴露于光照射后能够改变其物理和化学性质，从而能够模拟动态的天然细胞微环境，并在破译 3D 细胞微环境调节细胞命运的未知机制方面显示出巨大的潜力。已经有几篇综述总结了 PRH 的进展，并侧重于特定的光敏感化学基团和光响应元件，或 PRH 的反应类别和机制。然而，仍然缺少对新型 PRH 的整体观点，即强调可以通过远程光激活来调节的多种物理和化学性质，以及它们在体外工程动态细胞微环境以调节细胞行为方面的应用，这是本综述的重点。
