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) 中國科學家成功構建了一只擁有兩組DNA的嵌合猴，他們稱這項實驗將有利醫學研究和瀕危物種保護。 他們將來自一只犬齒猴（又稱食蟹猴或長尾獼猴，用于生物醫學研究）的干細胞注射入同一猴種一個基因獨特的胚胎內，這只猴子存活10天后被安樂死。研究人員說，這是世界上首次用干細胞構建的活產嵌合體靈長動物。 周四發表在科學雜志《細胞》上的概念驗證研究報告稱，值得注意的是，這只猴子是“高比例嵌合體”，身體各部分含有數量不等但相對占比較高的由注射干細胞分化而成的細胞。 這項研究的共同作者、中科院廣州生物醫藥與健康研究院首席研究員米格爾?埃斯特萬說：“令人鼓舞的是，在我們的活產嵌合體猴體內（干細胞）對大腦有很大貢獻，表明這種方法或可用于治療神經退行性疾病。” 他補充說：“如果能在兩種非人靈長類物種（其中一種瀕臨滅絕）之間實現嵌合體猴，那么嵌合體猴在物種保護方面也具有潛在的巨大價值。如果瀕危物種的供體細胞對種系有貢獻，通過繁殖可以復制瀕危物種?！?/p> 嵌合體一詞源于希臘神話中的怪異雜交生物，嵌合體小鼠最早出現在20世紀60年代，已普遍用于生物醫學研究。 嵌合實驗鼠讓科學家能夠追蹤正常細胞如何與基因改變或突變細胞相互作用，這對理解生命過程和疾病非常有用?？茖W家說，由于小鼠研究存在局限性，嵌合體猴的研究顯得意義重大。 該研究的資深作者中科院研究員劉真說：“因為小鼠生理機能與我們人類差別太大，它們無法再現很多人類疾病。由于人類和猴密切的進化關系，人類疾病可以更忠實地在猴身上還原?！?/p> 更具爭議的是人獸嵌合體，這種嵌合體含有人類細胞和來自其他物種的細胞。科學家們已經培育出了具有部分人類細胞的小鼠胚胎，2021年科學家報告說，他們培育出了人猴嵌合胚胎。科學家希望人類嵌合體有朝一日能滿足器官移植的需求。今年9月，研究人員報告說在豬胚胎中培育出了主要含有人體細胞的腎臟。 劉真在新聞通報會上說，構建猴與人類在早期胚胎發育階段之后的嵌合體是越過倫理紅線的行為。 研究顯示，嵌合體猴組織中干細胞的比例從21%到92%不等，在26種不同類型的身體組織中，平均比例為67%，腦組織中比例尤其高。 以色列魏茲曼科學研究所干細胞生物學和胚胎學教授雅各布?漢納說：“這是一篇非常重要的論文，研究有助于更好地制造基因突變猴，就像生物學家多年來所做的小鼠研究那樣?！?/p> (Translated by Debra) Words to Learn 相關詞匯 【干細胞】 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 | 