Airway gene delivery barriers

Physical and other barriers that can impede effective airway gene delivery have been mostly studied for adenoviral vectors. Less informalion is available for other viral vectors and for nonviral vectors. However, it is likely that many of die same barriers affecting adenoviral vector-mediated transduction of epithelial cells will also be applicable to other vectors. Additionally, nonviral vectors might be more affected by barriers than viral vectors. For example, normal mucins can significantly impede cationic liposome-mediated transfection but have less effect on transduction mediated by adenoviral vectors (2). Similarly, surfactants can decrease eationic liposome-mediated transfection by disruption of the liposomes with subsequent decrease in gene transfer (12X whereas administration of adenoviral veetors in surfactant can enhance gene expression (13,14). 

Efficient gene delivery is significantly limited by the multitude of barriers that serve to protect the lung against particle and bacterial insult. The upper airways... 

Pickles RJ. 2004. Physical and biological barriers to viral vector-mediated delivery of genes to the airway epithelium. Proc Am Thorac Soc. 1 302-308. 

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