The results presented in this article are only preliminary data. Currently, the most common vectors for gene transfer to the lung are replication-deficient adenoviruses. The major advantage of adenovectors is their excellent efficiency in gene transfer. However, gene expression is transient and the immunogenicity prevents repeated administrations. Moreover, the preparation of a gutless adenovirus with a more extended expression is technically demanding [42] . Figure 5 VP1 detection in type II cells. The cells were double-stained for VP1 and Pro-SP C as described in Materials and Methods. An SO lung is shown at the top row and ARDS lung in the bottom row. VP1 was detected by Cyte5 (red fluorescence, left panels) and Pro-SP C by FITC (green fluorescence, middle panels). The upper and lower right images show co-localization of both stainings inside alveolar type II cells (yellow). Shown at ×100 magnification After a detailed search of the literature data we can confirm that this is the first experiment in which an SV40 based vector was used for transduction of lung cells. The goal of our research was to provide a basis for the use of these vectors in face of their advantages over adenoviral vectors, as well as their limitations.