Core Viewpoint - Japan's Cabinet Office has reached a consensus to allow the use of human iPS cells to create fertilized eggs for non-reproductive, scientifically valid research purposes, with a cultivation period limited to 14 days and a prohibition on implanting fertilized eggs into human or animal uteri [1][2][4]. Group 1: Research Guidelines - The new guidelines permit the creation and handling of fertilized eggs only for non-reproductive and scientifically reasonable research purposes, with a maximum cultivation period of 14 days [2][4]. - The aim of allowing research on fertilized eggs is to gain insights into the mechanisms of early reproduction, which could help identify causes of infertility and genetic diseases [2][3]. Group 2: Historical Context and Developments - Previously, research using iPS cells was limited to creating sperm and eggs, but the new guidelines expand this to include fertilized eggs, provided existing rules for fertilized egg research are followed [2][3]. - Japan has been at the forefront of research in using iPS cells for reproductive mechanisms, with successful experiments in mice leading to the creation of offspring [2][3]. Group 3: Ethical Considerations - The report emphasizes the need for ethical consistency regardless of the source of the fertilized egg, as stated by experts involved in the ethical review [3][4]. - The cultivation of fertilized eggs is restricted to 14 days due to the onset of significant developmental processes, marking the beginning of individual development [4]. Group 4: International Context - The guidelines are based on international standards, with some regions like California allowing similar research under specific ethical reviews [4]. - The discussion of life ethics and the establishment of rules can enhance Japan's international standing in the field of stem cell research [4].

你肝脏（大阪大学提供） 武部教授小组从以往的研究中发现，维生素C和胆红素是形成肝脏结构的重要物质。他们将iPS细 胞分化为肝细胞后，分为两组，一组添加胆红素，另一组添加维生素C。胆红素是从细胞外添 加，而维生素C则通过改变基因使细胞自身能够合成。 大阪大学的武部贵则教授等利用iPS细胞制造出迷你肝脏 当将添加了胆红素和维生素C的肝细胞混合培养时，便形成了结构和功能与人类肝脏相似的类器 官。收集多个这种类器官，移植到处于肝衰竭状态的小鼠体内，结果显示其存活率及氨的分解能 力得到了提高。 今后，研究团队计划将这种类器官大型化，制作人工肝脏并进行临床试验，力争作为肝衰竭等疾 病的治疗方法尽早实现应用。研究成果已发表在英国科学期刊《自然》上。 武部教授等开发的迷 大阪大学武部贵则教授等人利用iPS细胞制造出了再现人类肝脏结构和功能的"类器官"。今后，研 究团队计划将这种类器官大型化，制作人工肝脏并进行临床试验，力争作为肝衰竭等疾病的治疗 方法尽早实现应用…… 大阪大学武部贵则教授等人的研究小组利用iPS细胞制造出了再现人类肝脏结构和功能的"类器官 （迷你器官）"。他们发现了在形成肝脏结构过程中至关重要的两种物质，并添 ...