Abstract: Objectives To establish allergic contact dermatitis (ACD) mouse models induced by dinitrofluorobenzene (DNFB) and fluorescein isothiocyanate (FITC), and investigate the pathogenesis of ACD. Methods Mice were sensitized by DNFB and FITC on the abdominal skin respectively, and challenged on the right ear, the left ear was treated with vehicle as the negative control. The thickness and degree of swelling of the ears were measured before and after the challenge. The histopathological changes were observed, and the expression levels of IL-2, IL-4, and IFN-γ in the ears and the lymph node cells (LNC) were detected with immunohistochemistry and ELISA, respectively. Results The thickness and swelling of right ears were significantly greater compared with the left ears (P<0.05). IL-2 was mainly expressed in the DNFB treated ears, and IL-4 in the FITC treated ears. In the LNC, IFN-γ was mainly expressed in the DNFB treated mice, and IL-4 in the FITC treated mice. Conclusions The Th1 ACD is induced by DNFB, and the Th2 ACD is induced by FITC. CD4⁺ and CD8⁺ T cells may play the key role in the pathogenesis of Th1 and Th2 ACD, respectively.

Key words: Dermatitis, allergic contact, Models, animal, Dinitrofluorobenzene, Fluorescein-5-isothiocyanate