Martinez-Garcia Francisco Drusso, Fischer Tony, Hayn Alexander, Mierke Claudia Tanja, Burgess Janette Kay, Harmsen Martin Conrad
Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Hanzeplein 1 (EA11), 9713 GZ Groningen, The Netherlands.
W.J. Kolff Research Institute, University Medical Center Groningen, University of Groningen, A. Deusinglaan 1, 9713 AV Groningen, The Netherlands.
Gels. 2022 Aug 26;8(9):535. doi: 10.3390/gels8090535.
The extracellular matrix (ECM) is a three-dimensional, acellular scaffold of living tissues. Incorporating the ECM into cell culture models is a goal of cell biology studies and requires biocompatible materials that can mimic the ECM. Among such materials are hydrogels: polymeric networks that derive most of their mass from water. With the tuning of their properties, these polymer networks can resemble living tissues. The microarchitectural properties of hydrogels, such as porosity, pore size, fiber length, and surface topology can determine cell plasticity. The adequate characterization of these parameters requires reliable and reproducible methods. However, most methods were historically standardized using other biological specimens, such as 2D cell cultures, biopsies, or even animal models. Therefore, their translation comes with technical limitations when applied to hydrogel-based cell culture systems. In our current work, we have reviewed the most common techniques employed in the characterization of hydrogel microarchitectures. Our review provides a concise description of the underlying principles of each method and summarizes the collective data obtained from cell-free and cell-loaded hydrogels. The advantages and limitations of each technique are discussed, and comparisons are made. The information presented in our current work will be of interest to researchers who employ hydrogels as platforms for cell culture, 3D bioprinting, and other fields within hydrogel-based research.
细胞外基质（ECM）是活组织的三维无细胞支架。将ECM纳入细胞培养模型是细胞生物学研究的一个目标，这需要能够模拟ECM的生物相容性材料。水凝胶就是这类材料之一：其聚合物网络的大部分质量来自水。通过调整其特性，这些聚合物网络可以类似于活组织。水凝胶的微观结构特性，如孔隙率、孔径、纤维长度和表面拓扑结构，可以决定细胞的可塑性。对这些参数进行充分表征需要可靠且可重复的方法。然而，大多数方法在历史上是使用其他生物样本进行标准化的，如二维细胞培养、活检甚至动物模型。因此，当应用于基于水凝胶的细胞培养系统时，它们的转换存在技术局限性。在我们目前的工作中，我们回顾了用于表征水凝胶微观结构的最常用技术。我们的综述简要描述了每种方法的基本原理，并总结了从无细胞和负载细胞的水凝胶中获得的汇总数据。讨论了每种技术的优点和局限性，并进行了比较。我们目前工作中提供的信息将对那些将水凝胶用作细胞培养、三维生物打印以及基于水凝胶研究的其他领域平台的研究人员感兴趣。
