Development of a novel, potent, safe, long-lasting lentivirus-based gene therapy for cystic fibrosis

囊性纤维化是一种常见的遗传性疾病，在英国有超过8000人患病。这是一种名为cftr的单一基因突变的结果，该基因导致肺部粘稠粘液的堆积。最终，肺部会反复感染和发炎，导致肺衰竭和过早死亡。目前所有的治疗方法都是针对症状的；没有治愈的方法。2001年，英国的三个研究小组成立了CF基因治疗联盟，以开发一种新的治疗方法，其基础是将新的(健康的)CFTR基因拷贝引入到CF患者的肺中。已经取得了许多进展，我们对这种方法的障碍已经了解了很多，但我们还不能为CF肺部疾病提供有效的基因治疗。这项研究应用的目的是使用一种新的基于慢病毒的基因疗法，我们认为这种病毒有可能更有效地将基因输送到肺部，并为CF肺部疾病提供一种有效的治疗方法。为了使携带Cf基因的慢病毒尽可能有效，它被两种名为F和HN的新外壳蛋白包裹，这一过程被称为“伪分型”。我们已经证明，当慢病毒带有F和HN的假型时，它在进入肺细胞时是有效的，它携带的基因可以在某些情况下表达数月，甚至数年。这种假型病毒表现出的另一个关键特征是它可以重复使用，这是我们以前在其他病毒中未曾见过的特性。这对于治疗慢性疾病有一个重要的优势，例如慢性纤维性心脏病，其影响持续到个人的一生。这项应用的目标是：i)改造病毒，使其适合患者使用；ii)改进病毒生产方法，使其能够生产出足够数量的病毒用于治疗；iii)了解与使用病毒相关的潜在副作用。这项研究项目长达18个月，我们希望在研究结束时选择出病毒的最终版本，我们可以在患者身上进行测试。如果我们成功地制造出这种病毒，并选择了一种合适的版本给患者，我们设想它可以通过一种名为雾化器的设备传递到CF患者的肺部，这种设备会产生一种可以呼吸的细雾。这种病毒效率的提高以及产生长期效应的能力意味着这可能形成一种新的、更有效的治疗CF的基础。

Cystic Fibrosis (CF) is a common genetic disease that affects over 8000 people in the UK. It is the result of a mutation in a single gene called CFTR that causes the build up of thick sticky mucus in the lungs. Eventually the lungs become repeatedly infected and inflamed, leading to lung failure and premature death. All current therapies are aimed at coping with the symptoms; there is no cure. In 2001, three research groups in the UK formed the CF Gene Therapy Consortium to develop a new kind of treatment based on introducing new (healthy) copies of the CFTR gene into the lungs of people with CF. Many advances have been made, and we have learned a great deal about the obstacles to this approach, but we are not yet in a position to offer an effective gene therapy for CF lung disease. The aim of this research application is to use a new kind of gene therapy based on a virus called lentivirus, which we think has the potential to be more efficient at delivering the gene into the lungs and to provide an effective treatment for CF lung disease. In order to make the lentivirus carrying the CF gene as effective as possible, it is wrapped up in two new coat proteins called F and HN, a process known as 'pseudotyping'. We have shown that when the lentivirus is pseudotyped with F and HN it is efficient at entering lung cells and the gene it carries can be expressed for many months, even years in some situations. Another key feature that this pseudotyped virus displays is that it can be repeatedly administered, a property we have not seen previously with other viruses. This has an important advantage for treating chronic diseases, such as CF where the effects last for the life-time of the individual. The objectives of this application are i) to engineer the virus so it is suitable for use in patients; ii) to improve virus production methods so that it can be made in sufficient quantities to use as a therapy; and iii) to understand the potential for side-effects associated with administering the virus. The research project is 18 months long and at the end of it we hope to have selected a final version of the virus that we can take forward to test in patients. If we are successful in manufacturing the virus and selecting a suitable version to give to patients, we envisage that it could be delivered to the lungs of CF individuals using a device called a nebuliser, which generates a fine mist that can be breathed in. The increased efficiency of this virus along with the ability to have an effect that is long-lived effect means that this could form the basis of a new, more effective treatment for CF.