The present invention demonstrates that VSV-G-pseudotyped lentivirus vectors efficiently transduce AEC in primary culture and in vivo with transduction favored by virus application from the apical side. Transduction efficiency in AEC increased with increasing MOI and greatly exceeded that achieved with a similarly pseudotyped MLV retrovirus vector. The present invention also demonstrates the successful in vivo transfer of genes through lentivirus vector transduction. Mammals injected with lentivirus vector via the trachea expressed the reporter protein in alveolar epithelial cells within 48 to 72 hours after infection.