Tunable Supramolecular Hydrogels for Selection of Lineage-Guiding Metabolites in Stem Cell Cultures
Tunable Supramolecular Hydrogels for Selection of Lineage-Guiding Metabolites in Stem Cell Cultures
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DOI：
10.1016/j.chempr.2016.07.001
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发表时间：
2016-08-11
期刊：
影响因子：
23.5
通讯作者：
Dalby, Matthew J.
中科院分区：
文献类型：
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作者：
Alakpa, Enateri V.;Jayawarna, Vineetha;Dalby, Matthew J.
众所周知，干细胞会根据培养它们的基质的化学和机械特性而分化。因此，具有可调特性的超分子生物材料非常适合干细胞分化的研究。在本报告中，我们利用这一现象，将干细胞在水凝胶中的分化与可变刚度和代谢组学分析相结合，以确定在分化过程中独特使用的特定生物活性脂质。为了实现这一目标，我们在不同硬度的超分子肽凝胶上培养血管周围干细胞，然后消耗代谢物。在软凝胶（1千帕）、硬凝胶（13千帕）和硬凝胶（32千帕）上，我们分别观察到神经元、软骨细胞和成骨细胞的分化，表明这些干细胞经历了刚度导向的命运选择。通过分析硬凝胶和硬凝胶分化过程中bbb600代谢物的浓度差异（分别关注软骨形成和成骨形成作为再生目标），我们发现特定脂质（分别是溶血磷脂酸和硫酸胆固醇）显著减少。因此，我们认为这些代谢物参与了分化过程。为了明确证明我们发现的脂质代谢物在驱动分化中发挥关键作用，我们随后证明，当将这些个体脂质饲喂到标准干细胞培养物中时，可以诱导向软骨细胞和成骨细胞表型的分化。我们的概念是利用超分子生物材料的设计作为一种策略来发现与治疗相关的细胞导向生物活性代谢物。
Stem cells are known to differentiate in response to the chemical and mechanical properties of the substrates on which they are cultured. Thus, supramolecular biomaterials with tunable properties are well suited for the study of stem cell differentiation. In this report, we exploited this phenomenon by combining stem cell differentiation in hydrogels with variable stiffness and metabolomics analysis to identify specific bioactive lipids that are uniquely used up during differentiation. To achieve this, we cultured perivascular stem cells on supramolecular peptide gels of different stiffness, and metabolite depletion followed. On soft (1 kPa), stiff (13 kPa), and rigid (32 kPa) gels, we observed neuronal, chondrogenic, and osteogenic differentiation, respectively, showing that these stem cells undergo stiffness-directed fate selection. By analyzing concentration variances of >600 metabolites during differentiation on the stiff and rigid gels (and focusing on chondrogenesis and osteogenesis as regenerative targets, respectively), we identified that specific lipids (lysophosphatidic acid and cholesterol sulfate, respectively), were significantly depleted. We propose that these metabolites are therefore involved in the differentiation process. In order to unequivocally demonstrate that the lipid metabolites that we identified play key roles in driving differentiation, we subsequently demonstrated that these individual lipids can, when fed to standard stem cell cultures, induce differentiation toward chondrocyte and osteoblast phenotypes. Our concept exploits the design of supramolecular biomaterials as a strategy for discovering cell-directing bioactive metabolites of therapeutic relevance.