IL-17 Modulates Immune Dysregulation and Skin Barrier Dysfunction in Oxazolone-Induced Dermatitis Murine Models

Abstract

BACKGROUND: Atopic dermatitis (AD) and contact dermatitis (CD) are known as T cell-mediated eczematous disorders. Interleukin (IL)-17 is expressed by Th17 cells, and involved in the recruitment of inflammatory cells into the AD and CD skin. In this study, we investigated whether IL-17 regulates immune dysregulation and skin barrier dysfunction in oxazolone-induced AD and CD-like murine model.MATERIALS AND METHODS: IL-17-/- and wild type mice were used to make oxazolone-induced AD and CD-like murine model. The ear swelling was measured by micrometer, and the skin biopsies were obtained for RNA isolation and histology. Quantitative real-time PCR analysis was performed to quantify mRNA expression of Th2 cytokines and antimicrobial peptides (AMPs). A vapometer, electron and confocal microscopy were used to evaluate structural changes in skin barrier.RESULT: Our data showed that AD and CD responses were alleviated in IL-17-/-mice. It was evidenced by reduced ear swelling, inflammatory cell infiltration and Th2 cytokines as inflammatory dysregulation in both IL-17-/-mice AD and CD. Skin barrier dysfunction was also characterized by reduced transepidermal water loss (TEWL) and lamellar bodies clustering, while increased lipid distribution in both IL-17-/-mice AD and CD. However, the inductions of AMP and barrier genes were significantly diminished in IL-17-/-mice AD only.CONCLUSION: These studies indic4ate that IL-17 gene may play a role to modulate immune dysregulation and skin barrier dysfunction in oxazolone-induced AD and CD