NOVEL METHOD FOR MUCOSAL GENE DELIVERY

通过受体介导的内吞作用将基因输送到靶细胞 这是一种非常吸引人的基因治疗策略。许多目标是 基因治疗是一种上皮细胞，它能使多种重要的 器官。例如，呼吸道细胞是主要的表达部位。 囊性纤维化跨膜电导调节剂(CFTR)，它 是囊性纤维化中的病变。上皮细胞有一个顶端 面向管腔的表面，以及面向下层的基侧表面 细胞。理想情况下，人们希望通过顶端或顶端传递基因 上皮细胞的管腔表面。例如，在肺部，有一种 可以通过引入呼吸道来传递基因，通过 灌输，甚至雾化。然而，根尖的表面 大多数上皮细胞对基因传递构成了强大的障碍。 大多数给药方法，如脂质体或病毒载体，非常有效 当应用于极化良好的上皮的根尖表面时，效果不佳 培养中的细胞，尤其是体内的细胞。这些受体通常是 用于受体介导的基因传递的基因都位于 基准面。根尖表面包含很少的受体， 高效地内吞。一种已用于基底外侧的受体 基因传递是聚合免疫球蛋白受体(PIgR)，它是 在表达CFTR的呼吸道细胞上尤其丰富。通常， PIgR的胞外结构域在根尖表面被切割， 这使得这种受体很难用于顶端基因的摄取。我们 我发现了一种新的方法来使用pIgR来寻找有效的顶端基因 领悟。在这项试点拨款提案中，我们将在培养的 呼吸道上皮细胞和整个大鼠肺内。

Delivery of genes to target cells by receptor-mediated endocytosis is a very appealing strategy for gene therapy. Many of the targets for gene therapy are epithelial cells that line a variety of important organs. For instance, airway cells are the main site of expression of the cystic fibrosis transmembrane conductance regulator (CFTR), which is the lesion in cystic fibrosis. Epithelial cells have an apical surface facing the lumen, and a basolateral surface facing underlying cells. Ideally, one would like to deliver genes through the apical or luminal surface of epithelial cells. In the lung, for instance, one could deliver the genes by introduction into the airways, via instillation or even aerosolization. However, the apical surface of most epithelial cells presents a formidable barrier to gene delivery. Most delivery methods, such as liposomes or viral vectors, work very poorly when applied to the apical surface of well polarized epithelial cells in culture or especially in vivo. The receptors that are usually used for receptor-mediated gene delivery are all located at the basolateral surface. The apical surface contains few receptors that are efficiently endocytosed. One receptor that has been used for basolateral gene delivery is the polymeric immunoglobulin receptor (pIgR), which is particularly abundant on the airway cells that express CFTR. Ordinarily, the extracellular domain of pIgR is cleaved off at the apical surface, which makes this receptor difficult to use for apical gene uptake. We have found a novel method to use the pIgR for effective apical gene uptake. In this pilot grant proposal we will test this in cultured airway epithelial cells and in the lungs of whole rats.