CFTR-mRNA delivery: a novel alternative for cystic fibrosis 'gene therapy'

Bangel-Ruland N, Tomczak K, Fernández EF, Leier G, Leciejewski B, Rudolph C, Rosenecker J, Weber WM

Abstract

BACKGROUND\nCystic Fibrosis (CF) is the most frequent lethal genetic disease in the Caucasian population. CF is caused by a defective gene coding for the cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP- and ATP-dependent Cl(-) channel and central regulatory protein in epithelia. CFTR influences the fluid composition of the mucus in the respiratory tract. The most common mutation inducing CF, ∆F508, impairs CFTR processing within the cell and thus prevents functional CFTR expression in the apical membrane. The aim of this study is to investigate the functional restoration of CFTR in human CF airway epithelia after transfection with optimized wtCFTR-mRNA.\nMETHODS\nWe used primary cultured human nasal epithelial (HNE) cells and the human bronchial epithelial cell line CFBE41o(-) that stably expresses ∆F508-CFTR and carried out transepithelial Ussing chamber measurements after transfection with optimized wtCFTR-mRNA. We confirmed the obtained data using immunofluorescence and protein biochemical approaches.\nRESULTS\nTransfection of the CFBE41o(-) cells with wtCFTR-mRNA restored cAMP-induced CFTR currents similar to the values seen in control cells (16HBE14o(-) ). Using immunofluorescence approaches we demonstrated that a considerable amount of CFTR is located at the apical surface or nearby regions in the CF cells after transfection. Western blot analyses of wtCFTR-mRNA transfected CFBE41o(-) cells confirmed these findings. Furthermore, we demonstrated physiological relevance by using primary cultured HNE cells and showed a nearly doubled increase in cAMP-stimulated CFTR current after transfection.\nCONCLUSION\nFrom these data we conclude that CFTR-mRNA transfection could be a novel alternative for gene therapy to restore impaired CFTR function. This article is protected by copyright. All rights reserved.