A powerful method for in vitro selection of normal versus cystic fibrosis airway epithelial cells

In preparation for a gene therapy approach to cystic fibrosis involving the precise repair of mutations on the CF gene by homologous recombination, we developed a method that would allow for selection of the CFTR+ cells originated in gene targeting experiments on CFTR- cells in vitro. The method is based on the differential sensitivity we observed between CFTR+ and CFTR- cells to agents stimulating cyclic adenosine monophosphate (cAMP). Controlled treatment with epinephrine or forskolin allows for selectively killing CFTR- cells. The efficiency of the selection method would make it suitable for rescuing the few corrected cells originated from rare homologous recombination events.