In conclusion, our findings indicate that the innovative reverse genetics system for studying HBoV1 infection that we describe here will enable us to elucidate the mechanism of HBoV1 replication and pathogenesis in a polarized HAE. Our system mimics natural HBoV1 infection of the in vivo human cartilaginous airway epithelia. The pathogenesis of HBoV1 in co-infection with other respiratory viruses and in conditions of lung diseases is a focus of future study. [43] ), as well as NuLi-1 and CuFi-8 (Tissue and Cell Culture Core, Center for Gene Therapy, University of Iowa). NuLi-1 and CuFi-8 were immortalized from normal and cystic fibrosis human primary airway cells, respectively, by expressing hTERT and HPV E6/E7 genes [44] . Primary Clonetics normal human bronchial/tracheal epithelial cells (NHBE) were purchased from Lonza (Walkersville, MD). Cells were cultured in media following instructions provided by the supplier.