The primary goal of this project was to compare in vivo gene expression levels of the cytokine, IL-4, and its natural splice variant, IL-4δ2, in the lungs of mice. Intratracheal replication-deficient adenovirus-mediated gene delivery of mouse IL-4 or IL-4δ2 was utilized to create three mice overexpressing IL-4 and three overexpressing IL-4δ2 in their lungs. An additional three mice were similarly infected with control AdV-NULL virus not encoding a cytokine. 14 days postinfection, lung tissue was homogenized, total RNA extracted, and results analyzed. The data demonstrate that IL-4 and its splice variant differentially affect global gene expression which has implications for the use of targeted therapy for various diseases. The dataset consists of 9 microarray data tables corresponding to each of the samples. Additionally, a supplementary TAR file of the raw data is also available to download.