Yuri Shunsuke, Nishikawa Masaki, Yanagawa Naomi, Jo Oak D, Yanagawa Norimoto
Medical and Research Services, Greater Los Angeles Veterans Affairs Healthcare System at Sepulveda, North Hills, CA 91343, USA; Department of Medicine, University of California at Los Angeles, David Geffen School of Medicine, Los Angeles, CA 90095, USA.
Medical and Research Services, Greater Los Angeles Veterans Affairs Healthcare System at Sepulveda, North Hills, CA 91343, USA; Department of Medicine, University of California at Los Angeles, David Geffen School of Medicine, Los Angeles, CA 90095, USA.
Stem Cell Reports. 2017 Feb 14;8(2):401-416. doi: 10.1016/j.stemcr.2016.12.011. Epub 2017 Jan 12.
A method to maintain and rebuild ureteric bud (UB)-like structures from UB cells in vitro could provide a useful tool for kidney regeneration. We aimed in our present study to establish a serum-free culture system that enables the expansion of UB progenitor cells, i.e., UB tip cells, and reconstruction of UB-like structures. We found that fibroblast growth factors or retinoic acid (RA) was sufficient for the survival of UB cells in serum-free condition, while the proliferation and maintenance of UB tip cells required glial cell-derived neurotrophic factor together with signaling from either WNT-β-catenin pathway or RA. The activation of WNT-β-catenin signaling in UB cells by endogenous WNT proteins required R-spondins. Together with Rho kinase inhibitor, our culture system facilitated the expansion of UB tip cells to form UB-like structures from dispersed single cells. The UB-like structures thus formed retained the original UB characteristics and integrated into the native embryonic kidneys.
一种在体外从输尿管芽（UB）细胞维持和重建类输尿管芽结构的方法可为肾脏再生提供有用工具。我们在本研究中的目标是建立一种无血清培养系统，该系统能够扩增UB祖细胞，即UB顶端细胞，并重建类输尿管芽结构。我们发现，成纤维细胞生长因子或视黄酸（RA）足以使UB细胞在无血清条件下存活，而UB顶端细胞的增殖和维持需要胶质细胞源性神经营养因子以及来自WNT-β-连环蛋白途径或RA的信号。内源性WNT蛋白激活UB细胞中的WNT-β-连环蛋白信号需要R-spondins。与Rho激酶抑制剂一起，我们的培养系统促进了UB顶端细胞的扩增，使其从分散的单细胞形成类输尿管芽结构。如此形成的类输尿管芽结构保留了原始UB的特征，并整合到天然胚胎肾脏中。
