Abstract:
Generating human organs inside interspecies chimeras might one day produce patient-specific organs for clinical applications, but further advances in identifying human chimera-competent pluripotent stem (PS) cells are needed. Moreover, the potential for human PS cells to contribute to the brains in human-animal chimeras raises ethical questions. The use of non-human primate (NHP) chimera-competent PS cells would allow one to test interspecies organogenesis strategies while also bypassing such ethical concerns. Here, we provide the first evidence for a putative chimera-competent pluripotent state in NHPs. Using histone deacetylase (HDAC) and selective kinase inhibition, we converted the PS cells of an Old World monkey, the African Green monkey (aGM), to an ERK-independent cellular state that can be propagated in culture conditions similar to those that sustain chimera-competency in rodent cells. The obtained stem cell lines indefinitely self-renew in MEK inhibitor-containing culture media lacking serum replacement and FGF. Compared to conventional PS cells, the novel stem cells express elevated levels of KLF4, exhibit more intense nuclear staining for TFE3, and manifest increased mitochondrial membrane depolarization. These data are preliminary but indicate that the key to deriving primate chimera-competent PS cells is to shield cells from the activation of ERK, PKC, and WNT signaling. Because of the similarity of aGMs to humans, the more ethically palatable use of NHP cells, and the more similar gestation length between aGMs and large animals such as sheep, the aGM cell lines described herein will serve as a useful tool for evaluating the efficacy and safety of interspecies organogenesis strategies. Future studies will examine chimera-competency and generalizability to human cells.
摘要:
在种间嵌合体中产生人体器官可能有一天会产生用于临床应用的患者特异性器官,但在鉴定人类嵌合多能干细胞(PS)方面还需要进一步的进展.此外,人类PS细胞在人类-动物嵌合体中对大脑有贡献的潜力引发了伦理问题。使用非人灵长类动物(NHP)嵌合体有能力的PS细胞将允许人们测试种间器官发生策略,同时也绕过了此类伦理问题。这里,我们为NHPs中推定的嵌合型多能状态提供了第一个证据.使用组蛋白去乙酰化酶(HDAC)和选择性激酶抑制,我们转化了旧世界猴子的PS细胞,非洲绿猴(aGM)可以在类似于在啮齿动物细胞中维持嵌合体能力的培养条件下繁殖的不依赖ERK的细胞状态。获得的干细胞系在缺乏血清替代物和FGF的含有MEK抑制剂的培养基中无限自我更新。与传统的PS细胞相比,新型干细胞表达升高的KLF4水平,表现出更强烈的TFE3核染色,并表现出增加的线粒体膜去极化。这些数据是初步的,但表明衍生灵长类嵌合体有能力的PS细胞的关键是保护细胞免受ERK的激活,PKC,和WNT信号。由于aGM与人类相似,NHP细胞在伦理上更可口的使用,和更相似的妊娠长度之间的aGM和大型动物如绵羊,本文所述的aGM细胞系将用作评估种间器官发生策略的功效和安全性的有用工具。未来的研究将检查嵌合体能力和对人类细胞的普适性。