Microenvironmental cues control pancreas cell fate and beta-cell maturation

摘要 目前通过细胞替代治疗1型糖尿病的策略受到以下因素的限制： 供体胰岛短缺;人多能干细胞（hPSC）衍生的β（hPSC-β）细胞 代表了解决这一困境的一个有希望的解决方案。改进目前的方法， hPSC向功能性β细胞的分化，全面了解 内分泌发育和β细胞过程的分子程序 成熟仍然是必需的。我们的初步研究表明，整合素信号和 微环境刚度在协调胰岛和β细胞中起着不可或缺的作用 发展本建议试图阐明整合素和 微环境刚度在协调这些复杂过程中发挥作用。我们的目标是 揭示整合素信号在控制1）内分泌细胞命运中的机制 决定，2）胰岛发育和3）β细胞成熟。我们将结合使用 胰腺、胰岛和β细胞特异性缺失小鼠模型，以抑制整联蛋白亚基 β 1（Itgb1，整合素信号传导所必需的亚基）。我们还致力于促进体外 通过控制微环境刚度来促进hPSC-β细胞的成熟。实现 为此，我们建立了一种新的细胞培养平台，用于时间控制细胞增殖。 微环境刚度通过培养和分化hPSC-β祖细胞， 在这个平台上，我们将阐明微环境刚度对β细胞的作用， 成熟总之，我们的研究将提供一个更好的理解的作用， 整合素信号传导和微环境刚性在调节β细胞发育中的作用。这 将为未来的功能性hPSC-β生成策略提供信息。

ABSTRACT Current strategies for treating type 1 diabetes via cell replacement are limited by a shortage of donor islets; human pluripotent stem cell (hPSC)-derived β (hPSC-β) cells represent a promising solution to this dilemma. To improve current methodologies for the differentiation of hPSCs towards functional β-cells, a comprehensive understanding of the molecular programs for the processes of endocrine development and β-cells maturation is still required. Our preliminary studies suggested that integrin signaling and microenvironment stiffness play an integral role in coordinating islet and β-cell development. The present proposal seeks to elucidate the role that integrin and microenvironment stiffness play in coordinating these complex processes. We aim to uncover the mechanisms of integrin signaling in controlling 1) endocrine cell fate decision, 2) islet development, and 3) β-cell maturation. We will utilize a combination of pancreas-, islet-, and β-cell-specific deletion mouse models to inactivate integrin subunit β1 (Itgb1, a subunit essential for integrin signaling). We also aim to promote in vitro maturation of hPSC-β cells by controlling the microenvironments stiffness. To achieve this, we established a novel cell culture platform for temporal control of microenvironment stiffness. By culturing and differentiating the hPSC-β progenitors on this platform, we will elucidate the role which microenvironment stiffness plays on β-cell maturation. Together, our study will provide a greater understanding of the role of integrin signaling and microenvironment stiffness in regulating β-cell development. This will inform future functional hPSC-β generation strategies.