根据英国《卫报》报道，在不久前亚特兰大举行的神经科学协会年会上，美国科学家首次展示了一种针对帕金森氏病的基因疗法，这种疗法可以实质性地缓解病患的症状而无需在患者体内植入任何器件。帕金森氏病是由于大脑中控制运动的部位缺失负责产生多巴胺的细胞。症状包括震颤以及肌无力。500人中即有一人患上这种疾病。
这项技术由美国生物技术公司Neurologix研发，主要是向患者大脑注入一种非致病性腺伴随病毒，持续时间大约100分钟，这种病毒被设计成可以打开一个控制多巴胺（一种神经递质）产生的基因。
在一期临床试验选择的参试病人来自纽约Presbyterian医院，他们患有晚期帕金森氏病，对任何目前的疗法均无反应。应用这种基因疗法后结果发现，根据帕金森氏病统一评价标准（UPDRS）计算，所有12名参试病人的症状都有至少25%的临床改善。12人中的9人平均临床改善度为37%，其中更有5人改善程度介于40%～65%之间，并且一年随访结果并未发现副作用。研究者称就目前的数据来看这种基因疗法可与目前的一些治疗方法如深度脑部刺激术相媲美，而且前者更简单，仅在局部麻醉的情况下即可施行，不会在患者体内植入任何器件。
研究者下一步的计划是尝试修正患者原有细胞，使其产生多巴胺，或者移植能够产生多巴胺的细胞来治疗这种疾病。
Gene therapy raises hope for Parkinson's sufferers
· Virus treatment found to boost all patients tested
· US study may pave way to less invasive procedure
Alok Jha, science correspondent
Wednesday October 18, 2006
The Guardian
Scientists have shown that the first gene-based therapy developed for Parkinson's disease substantially alleviates the symptoms of the condition without the need to leave any devices in the body.
The experimental treatment, carried out recently for the first time in humans by American scientists, involved infusing the brain for 100 minutes with a harmless virus that switched on a gene controlling the production of dopamine, a neurotransmitter chemical.
Parkinson's disease is caused by the loss of dopamine-producing cells in the part of the brain that controls movement. Symptoms include shaking and muscle weakness. One in 500 people suffers from the disease and around 10,000 people are diagnosed in the UK every year, mostly over the age of 50.
The results of the phase one clinical trial of the gene therapy, developed by the American biotech company Neurologix, found all 12 patients showed a clinical improvement of 25% as calculated on the Unified Parkinson's Disease Rating Scale (UPDRS) - a measure devised by doctors to track the long-term progress of Parkinson's patients. Nine of the 12 showed an average improvement of 37%, and five of those improved between 40% and 65%.
Phase one trials are designed to show that a new therapy is safe. A few patients are usually given different doses. Before it can be used widely the treatment must undergo two further stages of tests involving larger groups of patients over several years.
Current treatments for Parkinson's disease include directly replacing the lost dopamine, or inserting electrodes into the brain to stimulate it to produce it (deep brain stimulation). The electrodes stay in permanently, powered by an implanted pacemaker. "The next stage is to try and either empower the cells that are there to produce their own dopamine, or to put in cells that will produce dopamine themselves," said Kieran Breen, director of research at the Parkinson's Disease Society.
Matthew During of Neurologix used patients at the New York-Presbyterian Hospital with advanced Parkinson's disease who were not responding to any current treatments. Each patient received an infusion of the non-pathogenic adeno-- associated virus via a catheter inserted into the subthalamic nucleus, a part of the deep brain known to function abnormally in Parkinson's patients. The virus, which was designed to switch on a gene involved in making dopamine, was only exposed to half of each patient's brain
The results were presented yesterday at the Annual Meeting of the Society of Neuroscience in Atlanta.
The patients reported no side effects a year after the therapy, and all showed improved UPDRS scores on the side of their body that correlated to the treated part of their brain. The untreated side of the brain showed no improvement.
"This gene therapy trial is particularly unique and the clinical data unusually promising because the treatment was confined to just one side of the brain," said Dr During. In the next stage the company plans to infuse the treatment into both sides of the brain.
He added that the research aimed to work out whether it was possible to reset a specific group of overactive cells.
"The interim UPDRS scores are highly promising and, if they are borne out with additional data, would be comparable to results seen with deep brain stimulation. Unlike deep brain stimulation, however, our gene therapy approach is much simpler, can be carried out entirely under local anaesthesia, and avoids leaving any devices in the body," he said.
Dr Breen said the work being done by Neurologix was important to get past the current regime of just giving Parkinson's patients doses of dopamine. "We need to move on to the next stage which is to modify the function of the nerve cells."
http://www.guardian.co.uk/medicine/story/0,,1924703,00.html
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