Specifi c strategies have been developed to maximize uptake of vector into alveolar epithelial cells. It is possible to enhance lung transgene expression with the use of surface-active agents such as perfl urocarbon, which enhances the spread of vector and mixing within the epithelial lining fl uid [84] . Agents that reduce ubiquitination of AAV capsid proteins following endocytosis, such as tripeptide proteasome inhibitors, dramatically augment (>2,000-fold) AAV vector transduction in airway epithelia [85] .