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Cystic fibrosis transmembrane conductance regulator with a shortened R domain rescues the intestinal phenotype of CFTR-/- mice.

ABSTRACT: Gene transfer could provide a novel therapeutic approach for cystic fibrosis (CF), and adeno-associated virus (AAV) is a promising vector. However, the packaging capacity of AAV limits inclusion of the full-length cystic fibrosis transmembrane conductance regulator (CFTR) cDNA together with other regulatory and structural elements. To overcome AAV size constraints, we recently developed a shortened CFTR missing the N-terminal portion of the R domain (residues 708-759, CFTRΔR) and found that it retained regulated anion channel activity in vitro. To test the hypothesis that CFTRΔR could correct in vivo defects, we generated CFTR(-/-) mice bearing a transgene with a fatty acid binding protein promoter driving expression of human CFTRΔR in the intestine (CFTR(-/-);TgΔR). We found that intestinal crypts of CFTR(-/-);TgΔR mice expressed CFTRΔR and the intestine appeared histologically similar to that of WT mice. Moreover, like full-length CFTR transgene, the CFTRΔR transgene produced CFTR Cl(-) currents and rescued the CFTR(-/-) intestinal phenotype. These results indicate that the N-terminal part of the CFTR R domain is dispensable for in vivo intestinal physiology. Thus, CFTRΔR may have utility for AAV-mediated gene transfer in CF.

SUBMITTER: Ostedgaard LS

PROVIDER: S-EPMC3041073 | biostudies-other | 2011 Feb

REPOSITORIES: biostudies-other

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