Alternatively Spliced Variants of Interleukin-4 Promote Inflammation Differentially

IL-4d2 is a natural splice variant of IL-4 which lacks the region encoded by the second exon. Numerous recent reports suggested that the expression levels of IL-4d2 change in various diseases, especially those with pulmonary involvement, but the effects of IL-4d2 on the lungs in vivo have never been studied. Replication-deficient adenovirus-mediated gene delivery of mouse IL-4d2 to mouse lungs in vivo was used, and the effects compared with similar adenoviral delivery of mouse IL-4 or with infection with a NULL viral construct. The objective was to determine whether full-length wild-type Interleukin-4 encoded by exons 1-4 (IL-4) and alternatively spliced variant econded by exons 1,3, and 4 (IL-4d2) differentially affect gene expression in the lungs in vivo. The results show that IL-4d2 and IL-4 affected global gene expression differentially. Keywords: Comparative analysis of gene delivery of alternative splice variants in vivo There were three mice overexpressing mouse IL-4 in their lungs, three mice overexpressing mouse IL-4d2 in their lungs, and three mice similarly infected with control AdV-NULL virus not encoding a cytokine.