Stem cell regenerative potential owing to the capacity to self-renew as well as differentiate into other cell types is a promising avenue in regenerative medicine. Stem cell niche not only provides physical scaffolding but also possess instructional capacity as it provides a milieu of biophysical and biochemical cues. Extracellular matrix (ECM) has been identified as a major dictator of stem cell lineage, thus understanding the structure of in vivo ECM pertaining to specific tissue differentiation will aid in devising in vitro strategies to improve the differentiation efficiency. In this review, we summarize details about the native architecture, composition and mechanical properties of in vivo ECM of the early embryonic stages and the later adult stages. Native ECM from adult tissues categorized on their origin from respective germ layers are discussed while engineering techniques employed to facilitate differentiation of stem cells into particular lineages are noted. Overall, we emphasize that in vitro strategies need to integrate tissue specific ECM biophysical cues for developing accurate artificial environments for optimizing stem cell differentiation.

中文翻译：

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ECM的差异化：基质结构，组成和力学性能的综述。

由于自我更新和分化成其他细胞类型的能力，干细胞具有再生潜力，这在再生医学中是一个有前途的途径。干细胞生态位不仅提供物理支架，而且还具有指导能力，因为它提供了生物物理和生化线索的环境。细胞外基质（ECM）已被确定为干细胞谱系的主要决定因素，因此了解与特定组织分化有关的体内ECM结构将有助于设计提高分化效率的体外策略。在这篇综述中，我们总结了早期胚胎阶段和成年后期体内ECM的天然结构，组成和力学性能的详细信息。讨论了将成年组织的天然ECM分类为成年组织的起源，这些成年组织分别来自各个细菌层，同时注意到了用于促进干细胞分化为特定谱系的工程技术。总体而言，我们强调体外策略需要整合组织特异性ECM生物物理线索，以开发精确的人工环境以优化干细胞分化。