Division of Nephrology, Department of Medicine; and.
Department of Developmental Biology, Washington University in St. Louis School of Medicine, St. Louis, Missouri.
Clin J Am Soc Nephrol. 2020 Apr 7;15(4):550-556. doi: 10.2215/CJN.07470619. Epub 2020 Jan 28.
Methods to differentiate human pluripotent stem cells into kidney organoids were first introduced about 5 years ago, and since that time, the field has grown substantially. Protocols are producing increasingly complex three-dimensional structures, have been used to model human kidney disease, and have been adapted for high-throughput screening. Over this same time frame, technologies for massively parallel, single-cell RNA sequencing (scRNA-seq) have matured. Now, both of these powerful approaches are being combined to better understand how kidney organoids can be applied to the understanding of kidney development and disease. There are several reasons why this is a synergistic combination. Kidney organoids are complicated and contain many different cell types of variable maturity. scRNA-seq is an unbiased technology that can comprehensively categorize cell types, making it ideally suited to catalog all cell types present in organoids. These same characteristics also make scRNA-seq a powerful approach for quantitative comparisons between protocols, batches, and pluripotent cell lines as it becomes clear that reproducibility and quality can vary across all three variables. Lineage trajectories can be reconstructed using scRNA-seq data, enabling the rational adjustment of differentiation strategies to promote maturation of desired kidney cell types or inhibit differentiation of undesired off-target cell types. Here, we review the ways that scRNA-seq has been successfully applied in the organoid field and predict future applications for this powerful technique. We also review other developing single-cell technologies and discuss how they may be combined, using "multiomic" approaches, to improve our understanding of kidney organoid differentiation and usefulness in modeling development, disease, and toxicity testing.
大约 5 年前首次引入了将人类多能干细胞分化为肾类器官的方法，此后该领域取得了实质性的发展。各种方案生成的肾类器官结构越来越复杂，已被用于模拟人类肾脏疾病，并被用于高通量筛选。在此期间，用于大规模平行单细胞 RNA 测序（scRNA-seq）的技术也日趋成熟。现在，这两种强大的方法正在结合使用，以更好地了解肾类器官如何应用于理解肾脏发育和疾病。这是一个协同组合，原因有几个。肾类器官结构复杂，包含许多不同成熟程度的细胞类型。scRNA-seq 是一种无偏的技术，可以全面分类细胞类型，非常适合对类器官中存在的所有细胞类型进行分类。scRNA-seq 还具有定量比较不同方案、批次和多能细胞系的强大功能，因为越来越明显的是，这三个变量都存在可变性和重复性问题。可以使用 scRNA-seq 数据重建谱系轨迹，从而可以合理地调整分化策略，以促进所需的肾脏细胞类型的成熟或抑制不需要的非靶细胞类型的分化。在这里，我们回顾了 scRNA-seq 在类器官领域的成功应用，并预测了这一强大技术的未来应用。我们还回顾了其他正在发展的单细胞技术，并讨论了如何结合使用这些技术，采用“多组学”方法，以提高我们对肾类器官分化的理解以及在发育、疾病和毒性测试建模中的应用。
