Laboratory of Developmental Systems, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, 606-8507, Japan.
Laboratory for in vitro Histogenesis, RIKEN Center for Developmental Biology, Kobe, 650-0047, Japan.
Nat Commun. 2019 Aug 23;10(1):3802. doi: 10.1038/s41467-019-11702-y.
Limb development starts with the formation of limb buds (LBs), which consist of tissues from two different germ layers; the lateral plate mesoderm-derived mesenchyme and ectoderm-derived surface epithelium. Here, we report means for induction of an LB-like mesenchymal/epithelial complex tissues from murine pluripotent stem cells (PSCs) in vitro. The LB-like tissues selectively differentiate into forelimb- or hindlimb-type mesenchymes, depending on a concentration of retinoic acid. Comparative transcriptome analysis reveals that the LB-like tissues show similar gene expression pattern to that seen in LBs. We also show that manipulating BMP signaling enables us to induce a thickened epithelial structure similar to the apical ectodermal ridge. Finally, we demonstrate that the induced tissues can contribute to endogenous digit tissue after transplantation. This PSC technology offers a first step for creating an artificial limb bud in culture and might open the door to inducing other mesenchymal/epithelial complex tissues from PSCs.
肢体发育始于肢芽（LBs）的形成，肢芽由来自两个不同胚层的组织组成；侧板中胚层衍生的间充质和外胚层衍生的表面上皮。在这里，我们报告了从鼠多能干细胞（PSCs）体外诱导类似 LB 的间充质/上皮复合组织的方法。类似 LB 的组织选择性地分化为前肢或后肢型间充质，这取决于维甲酸的浓度。比较转录组分析表明，类似 LB 的组织表现出与 LB 中所见相似的基因表达模式。我们还表明，操纵 BMP 信号通路可使我们诱导出类似于顶外胚层嵴的增厚上皮结构。最后，我们证明诱导的组织在移植后可有助于内源性指组织的形成。该 PSC 技术为在培养中创建人工肢芽迈出了第一步，并可能为从 PSCs 诱导其他间充质/上皮复合组织开辟道路。
