Scientists based in China have created a monkey chimera with two sets of DNA, experimental work they say could ultimately benefit medical research and the conservation of endangered species. The monkey, which lived for 10 days before being euthanized, was made by combining stem cells from a cynomolgus monkey — also known as a crab-eating or long-tailed macaque, a primate used in biomedical research — with a genetically distinct embryo from the same monkey species. It’s the world’s first live birth of a primate chimera created with stem cells, the researchers said. A proof-of-concept study detailing the research, which published Thursday in the scientific journal Cell, said it was notable that the monkey was “substantially chimeric,” containing a varying but relatively high ratio of cells that grew out of the stem cells throughout its body. “It is encouraging that our live birth monkey chimera had a big contribution (of stem cells) to the brain, suggesting that indeed this approach should be valuable for modeling neurodegenerative diseases,” said study coauthor Miguel Esteban, principal investigator at the Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences. “Monkey chimeras also have enormous potential value for species conservation if they could be achieved between two types of nonhuman primate species, one of which is endangered,” he added. “If there is contribution of the donor cells from the endangered species to the germ line, one could envisage that through breeding animals of these species could be produced.” The term chimera originated from the monstrous hybrid creatures that populate Greek myths, and chimeric mice were first created in the 1960s and have been commonly used in biomedical research. Chimeric lab mice allow scientists to track how normal cells interact with genetically altered or mutated cells, which is useful for understanding biological processes and disease. But there are limitations with research on mice that make pursuing efforts with monkeys worthwhile, the scientists said. “Mice don’t reproduce many aspects of human disease, with their physiology so different from ours. In contrast, human and monkey are close evolutionary; so human diseases can be more faithfully modeled in monkeys,” said senior study author Liu Zhen of the Chinese Academy of Sciences. More controversial are human-animal chimeras, which contain some human cells, and some cells from other species. Scientists have created mouse embryos that are part human, and in 2021, scientists reported that they had grown human-monkey chimeric embryos. Scientists hope that part-human chimeras may one day help to fill the demand for organ transplants. In September, researchers reported that they had grown kidneys containing mostly human cells inside pig embryos. Liu said at a news briefing that it would be crossing an ethical red line to attempt to produce a monkey-human chimera beyond early embryonic stages of development. The percentage of stem cells in the monkey’s tissue ranged from 21% to 92%, with an average of 67% across the 26 different types of tissue that were tested, according to the study. The percentage was notably high in brain tissue. “It is a very important paper,” said Jacob Hanna, a professor of stem cell biology and embryology at the Weizmann Institute of Science in Israel who was not involved with the study. “This study may contribute to easier and better making of mutant monkeys, just like biologists have been doing for years with mice,” Hanna added. (SD-Agencies) 中国科学家成功构建了一只拥有两组DNA的嵌合猴，他们称这项实验将有利医学研究和濒危物种保护。 他们将来自一只犬齿猴（又称食蟹猴或长尾猕猴，用于生物医学研究）的干细胞注射入同一猴种一个基因独特的胚胎内，这只猴子存活10天后被安乐死。研究人员说，这是世界上首次用干细胞构建的活产嵌合体灵长动物。 周四发表在科学杂志《细胞》上的概念验证研究报告称，值得注意的是，这只猴子是“高比例嵌合体”，身体各部分含有数量不等但相对占比较高的由注射干细胞分化而成的细胞。 这项研究的共同作者、中科院广州生物医药与健康研究院首席研究员米格尔•埃斯特万说：“令人鼓舞的是，在我们的活产嵌合体猴体内（干细胞）对大脑有很大贡献，表明这种方法或可用于治疗神经退行性疾病。” 他补充说：“如果能在两种非人灵长类物种（其中一种濒临灭绝）之间实现嵌合体猴，那么嵌合体猴在物种保护方面也具有潜在的巨大价值。如果濒危物种的供体细胞对种系有贡献，通过繁殖可以复制濒危物种。” 嵌合体一词源于希腊神话中的怪异杂交生物，嵌合体小鼠最早出现在20世纪60年代，已普遍用于生物医学研究。 嵌合实验鼠让科学家能够追踪正常细胞如何与基因改变或突变细胞相互作用，这对理解生命过程和疾病非常有用。科学家说，由于小鼠研究存在局限性，嵌合体猴的研究显得意义重大。 该研究的资深作者中科院研究员刘真说：“因为小鼠生理机能与我们人类差别太大，它们无法再现很多人类疾病。由于人类和猴密切的进化关系，人类疾病可以更忠实地在猴身上还原。” 更具争议的是人兽嵌合体，这种嵌合体含有人类细胞和来自其他物种的细胞。科学家们已经培育出了具有部分人类细胞的小鼠胚胎，2021年科学家报告说，他们培育出了人猴嵌合胚胎。科学家希望人类嵌合体有朝一日能满足器官移植的需求。今年9月，研究人员报告说在猪胚胎中培育出了主要含有人体细胞的肾脏。 刘真在新闻通报会上说，构建猴与人类在早期胚胎发育阶段之后的嵌合体是越过伦理红线的行为。 研究显示，嵌合体猴组织中干细胞的比例从21%到92%不等，在26种不同类型的身体组织中，平均比例为67%，脑组织中比例尤其高。 以色列魏兹曼科学研究所干细胞生物学和胚胎学教授雅各布•汉纳说：“这是一篇非常重要的论文，研究有助于更好地制造基因突变猴，就像生物学家多年来所做的小鼠研究那样。” (Translated by Debra) Words to Learn 相关词汇 【干细胞】 gànxìbāo stem cell an unspecialized cell that gives rise to differentiated cells 【嵌合的】 qiànhé de chimeric containing tissue with two or more genetically distinct populations of cells | 