Generating teeth in vitro requires mimicking tooth developmental processes. Biomaterials are essential to support 3D tooth organoid formation, but their properties must be finely tuned to achieve the required biomimicry for tooth development. For the first time, we used bioorthogonally cross-linked hydrogels as defined 3D matrixes for tooth developmental engineering, and we highlighted how their properties play a pivotal role in enabling 3D tooth organoid formation in vitro. We prepared hydrogels by mixing gelatin precursors modified either with tetrazine (Tz) or norbornene (Nb) moieties. We tuned the hydrogel properties (E = 2–7 kPa; G′ = 500–1500 Pa) by varying the gelatin concentration (8% vs 12% w/V) and stoichiometric ratio (Tz:Nb = 1 vs 0.5). We encapsulated dental epithelial-mesenchymal cell pellets in a library of hydrogels and identified a hydrogel formulation that enabled successful growth kinetics and morphogenesis of tooth germs, introducing a defined tunable platform for tooth organoid engineering and modeling.

中文翻译：

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使用定义的生物正交交联水凝胶生成牙齿类器官


在体外生成牙齿需要模拟牙齿发育过程。生物材料对于支持 3D 牙齿类器官的形成至关重要，但必须对其特性进行微调，以实现牙齿发育所需的仿生学。我们首次使用生物正交交联水凝胶作为牙齿发育工程的定义 3D 基质，我们强调了它们的特性如何在体外实现 3D 牙齿类器官形成中发挥关键作用。我们通过将明胶前体与丁嗪 （Tz） 或降冰片烯 （Nb） 部分改性来制备水凝胶。我们调整了水凝胶特性 （E = 2–7 kPa;G′ = 500–1500 Pa），通过改变明胶浓度（8% 对 12% w/V）和化学计量比（Tz：Nb = 1 对 0.5）。我们将牙科上皮-间充质细胞沉淀封装在水凝胶库中，并确定了一种水凝胶配方，该配方能够成功实现牙齿胚芽的生长动力学和形态发生，为牙齿类器官工程和建模引入了一个定义的可调平台。