CFTR gene delivery to human airway epithelia using parainfluenza virus 5 amplifying virus-like particles.

Parainfluenza virus 5 (PIV5)-derived amplifying virus-like particles (PIV5-AVLPs) are an efficient gene delivery platform with broad cell tropism. To investigate the feasibility of using PIV5-AVLPs for cystic fibrosis (CF) gene therapy, we generated AVLPs expressing enhanced green fluorescent protein (AVLP-eGFP) or a codon-optimized human cystic fibrosis transmembrane conductance regulator (CFTR) coding sequence and an mCherry reporter (AVLP-CFTR). We examined the transduction efficiency and persistence of transgene expression of AVLP-eGFP in primary cultures of non-CF and CF human airway epithelia (HAE). When applied to the apical surface of HAE, the AVLP-eGFP mainly transduced ciliated epithelial cells, with lesser targeting to secretory and basal cells. Reporter transgene expression gradually diminished over a 1-month time course. Transducing approximately 15% of CF airway epithelial cells with AVLP-CFTR was sufficient to restore CFTR-dependent short-circuit current to levels similar to non-CF epithelia. Our results demonstrate that PIV5-AVLPs delivered to the apical side of HAE efficiently transduce sufficient epithelial cells to restore functional CFTR expression. PIV5-based AVLPs provide a versatile platform for the delivery of a variety of genetic cargoes to the respiratory tract.