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It was nearly a decade in the making, but the first human trial using embryonic stem cells was approved on Friday. The trial, which will test a stem-cell-based treatment for spinal-cord injury, will begin later this summer and will use cells generated by Geron Corp. The approval marks the first time human stem cells, extracted and grown from embryos, will be transplanted into patients. Adult stem cells, which are present in many types of tissue, have been used in treatments for years — the most common being bone-marrow transplants in cancer care — but an embryonic study is a whole new thing....

It was nearly a decade in the making, but the first human trial using embryonic stem cells was approved on Friday. The trial, which will test a stem-cell-based treatment for spinal-cord injury, will begin later this summer and will use cells generated by Geron Corp. The approval marks the first time human stem cells, extracted and grown from embryos, will be transplanted into patients. Adult stem cells, which are present in many types of tissue, have been used in treatments for years — the most common being bone-marrow transplants in cancer care — but an embryonic study is a whole new thing. There's a good reason it's being greeted with so much excitement. Scientists believe that embryonic stem cells are more versatile than adult cells in generating the more than 200 different tissue types in the body. The need for healthy new cells is particularly acute in the case of spinal-cord injury, because once central-nervous-system tissue is destroyed, it does not regenerate — not in any significant way, at least. The Geron team began its work with what is known as a presidential stem-cell line — stem cells derived from discarded in vitro–fertilization embryos that already existed in 2001 when then President Bush decided to prohibit the use of federal funds to pursue human embryonic-stem-cell work. At the time, fewer than two dozen of these stem-cell lines were of good enough quality to use as a basis for human treatments.

這項工作已經進行了將近十年，但是星期五首次批准了使用胚胎幹細胞的首次人體試驗。該試驗將測試基於乾細胞的脊髓損傷治療方法，該試驗將於今年夏季晚些時候開始，並將使用Geron Corp.產生的細胞。批准標誌著人類首次從胚胎中提取和生長的人類幹細胞將首次獲得批准。被移植到病人身上。成年干細胞存在於許多類型的組織中，已經在治療中使用了多年（最常見的是癌症護理中的骨髓移植），但是胚胎研究是一門嶄新的事物。有一個很好的理由讓它感到如此興奮。科學家認為，胚胎幹細胞在體內產生200多種不同組織類型方面比成年細胞更具通用性。在脊髓損傷的情況下，對健康新細胞的需求尤其迫切，因為一旦中樞神經系統組織被破壞，它就不會再生-至少沒有任何重要的方式。 Geron小組從所謂的總統幹細胞系開始工作，這種干細胞係從2001年就已經存在的廢棄的體外受精胚胎衍生而來，當時布什總統決定禁止使用聯邦資金從事人類胚胎培養。幹細胞工作。當時，這些幹細胞系中只有不到十二種具有足夠好的質量，可以用作人類治療的基礎。