英國首次用基因編輯治好白血病女孩

A treatment that uses “molecular scissors” to edit genes has been used for the first time by UK medics successfully to treat a one-year-old girl with an “incurable” form of leukaemia.

英國醫生第一次依靠使用“分子剪刀”修改基因的療法，成功地治癒了一名患有“無法治癒的”白血病的1歲女孩。

The case at Great Ormond Street Hospital in London involved the creation of “designer immune cells” programmed to hunt and kill the disease. The girl, called Layla, is now cancer free and doing well, according to the hospital.

倫敦大奧蒙德街醫院(Great Ormond Street Hospital)的這一病例，生成經過設計的“人工培育的免疫細胞”去捕捉並治療疾病。醫院稱，這個名叫“萊拉”(Layla)的女孩目前擺脫了癌症，身體狀況很不錯。

The breakthrough will add to excitement over the fast-emerging field of gene-editing — a type of genetic engineering in which DNA is inserted, replaced or removed from genes to fix faults or fight disease.

這次突破將令人對基因編輯這一快速發展的新興領域感到更加興奮。基因編輯是基因工程的一種，向基因中插入DNA，替換或取下其中的DNA，從而修復缺陷或戰勝疾病。

Gene-editing has caused controversy because of its potential to be used in ethically dubious ways, such as the creation of “designer babies”. However, the London success helps show why many scientists are so enthusiastic about the technology.

基因編輯引發了爭議，因爲它可能導致令人產生道德疑慮的用法，比如生成“設計嬰兒”。然而，這家倫敦醫院的成功也證明，爲何很多科學家那麼熱衷於這項技術。

The so-called UCART19 cells used at Great Ormond Street had shown promise in animals but had never been used in humans before they were administered as a last-ditch attempt to save Layla after other drugs failed.

大奧蒙德街醫院使用的所謂UCART19細胞在動物身上已顯出良好前景，但除了此次爲救活萊拉而做的最後努力之前，該細胞從未應用於人體。此前在萊拉身上使用的其他藥物全部失敗了。

The treatment, developed by a French biotech company called Cellectis, consisted of 1ml of UCART19 cells injected into Layla’s bloodstream. After several weeks it was clear the leukaemia cells were disappearing.

這一療法是由法國生物科技公司Cellectis開發出來的，把1毫升的UCART19細胞注入了萊拉的血流中。幾周後，白血病細胞明顯開始消失。

The treatment is similar to cancer therapies in development using modified T-cells from companies including Novartis of Switzerland and Juno and Kite of the US. However, whereas others use cells extracted from the patient’s own blood, UCART19 cells come from healthy donors.

該療法類似於瑞士的諾華製藥(Novartis)以及美國的Juno和Kite等公司開發的使用修飾T細胞治療癌症的辦法。然而，其他療法使用從病人自身血液中提取的細胞，而UCART19細胞則來自於健康的捐獻者。

This overcomes the problem of many leukaemia patients not having enough healthy T-cells — a type of white blood cell that fights off disease — to be harvested after chemotherapy.

這就克服了從化療後的許多白血病患者體內難以提取到足量健康T細胞的難題。T細胞是一種能夠對抗疾病的白血細胞。

A further possible advantage is that donor cells can be mass produced for use in any patient, making them potentially more affordable than rival treatments that must be personalised for each individual. High costs are viewed as one of the biggest drawbacks of the so-called CAR-T therapies under development by Novartis, Juno and Kite.

一個更有可能的優勢在於，捐贈細胞可以大規模生產，並用於任何患者，與因患者而異的其他療法相比，在成本上更低。諾華製藥、Juno和Kite正在研製中的所謂CAR-T療法的最大缺點之一，就是被認爲價格太高。