Directing the fate of human pluripotent stem cells (hPSCs) into different lineages requires variable starting conditions and components with undefined activities, introducing inconsistencies that confound reproducibility and assessment of specific perturbations. Here we introduce a simple, modular protocol for deriving the four main ectodermal lineages from hPSCs. By precisely varying FGF, BMP, WNT, and TGFβ pathway activity in a minimal, chemically defined medium, we show parallel, robust, and reproducible derivation of neuroectoderm, neural crest (NC), cranial placode (CP), and non-neural ectoderm in multiple hPSC lines, on different substrates independently of cell density. We highlight the utility of this system by interrogating the role of TFAP2 transcription factors in ectodermal differentiation, revealing the importance of TFAP2A in NC and CP specification, and performing a small-molecule screen that identified compounds that further enhance CP differentiation. This platform provides a simple stage for systematic derivation of the entire range of ectodermal cell types.

中文翻译：

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一个模块化的平台，用于将人类PSC分化为所有主要的表皮细胞系。

将人类多能干细胞（hPSC）的命运控制在不同的谱系中，需要可变的起始条件和具有不确定活动的成分，从而引入不一致之处，从而混淆了再现性和特定扰动的评估。在这里，我们介绍了一个简单的模块化协议，用于从hPSC派生四个主要的外胚层谱系。通过在最小的化学成分确定的培养基中精确改变FGF，BMP，WNT和TGFβ途径的活性，我们显示了神经外皮，神经c（NC），颅内斑（CP）和非神经外皮的平行，稳健且可重现的派生在多个hPSC系中，可以在不同的底物上独立于细胞密度。通过询问TFAP2转录因子在外胚层分化中的作用，我们强调了该系统的实用性，揭示了TFAP2A在NC和CP规范中的重要性，并进行了小分子筛选，确定了进一步增强CP分化的化合物。该平台为系统推导整个表皮细胞类型范围提供了一个简单的阶段。