Pfizer 金援UK Peter Coffey 胚胎幹細胞 治療黃斑部病變（AMD）

幹細胞移植 首例治黃斑部病變手術成功發稿時間：2015/09/29 10:11 最新更新：2015/09/29 10:11 （中央社倫敦29日綜合外電報導）英國一間眼科醫院與美國輝瑞大藥廠（Pfizer）共同研發出一項創新治療，為罹患可能導致失明的老年性黃斑部病變患者，移植從胚胎幹細胞萃取的細胞，首位接受治療的患者手術成功。路透社報導，位於倫敦的莫菲爾眼科醫院（Moorfields Eye Hospital）表示，在針對治療「濕性」老年性黃斑部病變（AMD）的臨床試驗有10位患者參與，首位患者的手術結果相當「成功」。這項臨床試驗的目的，是測試移植從胚胎幹細胞萃取的視網膜色素上皮細胞（RPE）的安全性與效果。幹細胞是人體再生系統的主要母細胞，具自我更新能力並可分化成各種細胞。贊成使用胚胎幹細胞的科學家聲稱，幹細胞能扭轉醫療，能醫治失明、青少年糖尿病或其他嚴重傷害；但是另一派則基於幹細胞是從人類胚胎萃取而成，因而反對使用。醫師利用人體胚胎幹細胞轉化成視網膜色素上皮細胞，然後用這些幹細胞培養的新組織，注入患者的視網膜，來取代那些因眼疾受傷即將死亡的細胞。黃斑部位在眼球正後方的視網膜中心，是視覺最敏銳的部位。莫菲爾眼科醫院今天表示，首位患者在上月接受治療，「迄今沒有出現任何併發症」，手術團隊希望能在12月初以前判定初步視力恢復情形。老年性黃斑部病變占已開發國家所有失明或視力受損原因的近5成，好發於50歲以上的長者。依臨床病灶可分成乾性病變及濕性病變，大部份患者屬於乾性病變，濕性病變可能因脈絡膜新生血管產生黃斑部水腫、出血等現象，造成視力嚴重減退。（譯者：中央社陳怡君）

Stem cell trial aims to cure blindness 2015/9/29 Fergus Walsh  About one in four over-60s in the UK has age-related macular degeneration Surgeons in London have carried out a pioneering human embryonic stem cell operation in an ongoing trial to find a cure for blindness for many patients. The procedure was performed on a woman aged 60 at Moorfields Eye Hospital. It involved "seeding" a tiny patch with specialised eye cells and implanting it at the back of the retina. The London Project to Cure Blindness was established a decade ago to try to reverse vision loss in patients with age-related macular degeneration (AMD). Ten patients with the wet form of AMD will undergo the procedure. All will have suffered a sudden loss of vision as a result of defective blood vessels in the eye. They will be monitored for a year to check that the treatment is safe and whether their vision improves. The woman who was the patient - and does not wish to be named - had the operation last month. Prof Peter Coffey, of the UCL Institute of Ophthalmology, who is co-leading the London Project, said: "We won't know until at least Christmas how good her vision is and how long that may be maintained, but we can see the cells are there under the retina where they should be and they appear to be healthy." The cells being used form the retinal pigment epithelium (RPE) - the layer of cells that nourish and support the photoreceptors in the macula - the seeing part of the eye. In macular degeneration, the RPE cells die, and as a result the eye loses function. Patients with AMD lose their central vision, which becomes distorted and blurred. The cells used in the operation were originally derived from a donated early embryo - smaller than a pinhead - which has the potential to become any cell in the body. Prof Lyndon Da Cruz of Moorfields Eye Hospital, who carried out the surgery, said: "This is truly a regenerative project. In the past it's been impossible to replace lost neural cells. "If we can deliver the very layer of cells that is missing and give them their function back this would be of enormous benefit to people with the sight-threatening condition". If the treatment is successful, the scientists say, it would also help patients in the early stages of dry AMD, and could potentially halt their vision loss. AMD affects more than 600,000 people in the UK and is the leading cause of sight loss in the developed world. It is estimated that one in every 10 people over 65 has some degree of AMD. The team at Moorfields is working in partnership with the pharmaceutical company Pfizer, which is funding the trial. It is not known how much the one-off surgical treatment might cost, although the scientists involved point out that treating and dealing with sight loss is a huge burden on the NHS. It is not the first time that scientists have used stem cells derived from human embryos in patients with sight loss. In 2012, patients with Stargardt's disease - which leads to progression deterioration of vision - were injected with embryonic stem cells in a safety trial carried out in the US and UK - which also involved a team at Moorfields. Of more relevance to the current trial are the 40 AMD patients already treated at Moorfields with cells taken from their own eyes. Prof Da Cruz said "We saw extraordinary recovery, with some people being able to read again and drive, and that recovery being sustained for years." He explained that using the patient's own cells was complex and carried risks, which is why the London Project opted for the embryonic stem cell line, which can produce a limitless supply of specialist cells.

Prof Da Cruz said animal studies had shown that surgery to introduce the sheet of cells into the eye was feasible. So although the team cannot say whether this trial will work, the years of planning give them confidence that this treatment has huge potential. It is far too early to make any judgment, but if successful, it would be a stunning medical advance of huge implications. The results from the first patient, and subsequent volunteers, will be eagerly awaited.