Department of Kidney Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811, Japan.
Department of Kidney Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811, Japan; Department of Urology, Kyushu University Graduate School of Medical Science, Fukuoka 812-8582, Japan.
Stem Cell Reports. 2019 Aug 13;13(2):322-337. doi: 10.1016/j.stemcr.2019.07.003. Epub 2019 Aug 1.
Kidney formation is regulated by the balance between maintenance and differentiation of nephron progenitor cells (NPCs). Now that directed differentiation of NPCs from human induced pluripotent stem cells (iPSCs) can be achieved, maintenance and propagation of NPCs in vitro should be beneficial for regenerative medicine. Although WNT and FGF signals were previously shown to be essential for NPC propagation, the requirement for BMP/TGFβ signaling remains controversial. Here we reveal that activin has superior effects to BMP7 on maintenance efficiency of human iPSC-derived NPCs. Activin expanded ITGA8/PDGFRA/SIX2-GFP NPCs by 5-fold per week at 80%-90% efficiency, and the propagated cells possessed robust capacity for nephron formation both in vitro and in vivo. The expanded cells also maintained their nephron-forming potential after freezing. Furthermore, the protocol was applicable to multiple non-GFP-tagged iPSC lines. Thus, our activin-based protocol will be applicable to a variety of research fields including disease modeling and drug screening.
肾脏的形成受到肾祖细胞（NPC）维持和分化之间平衡的调控。现在已经可以从人诱导多能干细胞（iPSC）中定向分化 NPC，因此 NPC 的体外维持和增殖应该有利于再生医学。尽管先前的研究表明 WNT 和 FGF 信号对于 NPC 的增殖是必需的，但 BMP/TGFβ 信号的需求仍然存在争议。在这里，我们揭示了激活素在维持人 iPSC 衍生 NPC 的效率方面比 BMP7 具有更好的效果。激活素以每周 5 倍的效率将 ITGA8/PDGFRA/SIX2-GFP NPC 扩增 5 倍，并且增殖的细胞具有强大的体外和体内肾形成能力。经过冷冻保存后，扩增的细胞仍保持其肾形成潜能。此外，该方案适用于多个非 GFP 标记的 iPSC 系。因此，我们基于激活素的方案将适用于多种研究领域，包括疾病建模和药物筛选。
