Correction and measurement of the basic defects in cystic fibrosis

由遗传性疾病囊性纤维化(CF)引起的呼吸道疾病目前无法预防或治愈。目前的治疗方法(肺移植除外)只能减缓不可避免的肺健康下降。许多CF患者会因肺衰竭而过早死亡。我们开发了一种基因转移技术，将纠正基因(CFTR)导入到CF病变的呼吸道细胞中。我们已经用小鼠的呼吸道来测试和开发这种方法，以确定是否可以实现呼吸道细胞的长期遗传校正。这种基因作为一种小剂量的特殊递送颗粒(载体)被引入呼吸道，这种颗粒(载体)是使用高度修饰的HIV-1病毒成分构建的。如果最终在患有CF的人类身上取得成功，这种疾病应该被阻止，甚至治愈。我们最近的工作表明，我们已经能够将该基因插入到呼吸道祖细胞中，证实了我们的假设，即可以通过这种方式实现长期的基因表达。为了知道这种方法在人类身上是否安全有效，我们现在必须在绵羊(人体大小的肺)和绒猴(人体大小的肺)上测试这项技术，然后才能考虑临床试验。我们将对动物进行长达3年的监测，以确保基因的影响真正持久，我们将记录基因转移载体是如何从体内消失的。我们还发现了一种新的方法来检查呼吸道表面非常薄的流体层的细节。这种液体在CF呼吸道中太浅(允许细菌粘在一起并引发疾病)，因此成功的基因治疗应该使液体返回到适当的深度。这种方法使用来自同步加速器的X射线，我们预计它将在不需要牺牲动物来测量呼吸道表面的情况下发挥作用。如果成功，它也有可能被用来测试基因疗法是否有效，就像对患有CF的人类进行普通X光检查一样。

Airway disease caused by the genetic disease cystic fibrosis (CF) cannot currently be prevented or cured. Current treatments (other than lung transplant) can only slow the inevitable decline in lung health. Early death from lung failure occurs for many with CF. We have developed a gene transfer technique to introduce the corrective gene (CFTR) into CF-diseased airway cells. We have used airways in mice to test and develop this method, to determine if long-lasting genetic correction of the airway cells can be achieved. The gene is introduced into the airway as a single small dose of special delivery-particles (vector) that have been built using highly-modified components of the HIV-1 virus. If ultimately successful in humans with CF, the disease should be halted, or even cured. Our recent work indicates that we have been able to insert the gene into airway progenitor cells, confirming our hypothesis that long-lasting gene expression can be achieved this way. To know if the method would be safe and effective in humans, we must now test the technique in sheep (as a human-size lung) and in marmosets (as a human-like lung) before clinical trials could be considered. We will monitor animals for up to 3 years to be sure the effect of the gene is truly long-lasting, and we will document how the gene-transfer vector disappears from the body. We have also discovered a new way to examine the detail of the very thin fluid layer on the airway surface. This fluid is too shallow in CF airway (allowing bacteria to stick and start disease) and so a successful gene therapy should return the fluid to it's proper depth. This method uses X-ray light from a synchrotron, and we expect it will work without the need to sacrifice animals to measure the airway surface. If successful it also has potential to be used much like a normal X-ray in humans with CF, to test if a gene therapy has worked.