Th2 immune response plays a critical role in the development of nickel-induced allergic contact dermatitis.

BACKGROUND: The precise roles of T helper (Th)1-type and Th2-type cytokine responses in nickel (Ni)-induced allergic contact dermatitis have not yet been clearly defined. We investigated the involvement of Th2 cytokines in Ni-induced contact hypersensitivity reaction using GATA-3 transgenic (Tg) mice. METHODS: A Ni-titanium (Ti) alloy was implanted under the skin of GATA-3 Tg mice. A Ni solution was then injected 1 month after sensitization. The ear swelling response was measured at several time points after the injection; the cytokine levels in the skin were measured at 48 h after injection, and the serum levels of IgE were measured 1 month after injection. In addition, purified CD4+ splenic cells obtained from the GATA-3 Tg mice sensitized with the Ni-Ti alloy were infused into Rag-2(-/-) mice, and the ear swelling response of these mice after a further challenge with Ni solution was also measured. RESULTS: Marked ear swelling and elevated serum IgE levels and skin tissue levels of IL-4 were observed in Ni-Ti-sensitized GATA-3 Tg mice. The Rag-2(-/-) mice transfused with the CD4+ splenic cells from the Ni-Ti alloy sensitized GATA-3 Tg mice showed a significantly more pronounced ear swelling response than the control mice. CONCLUSION: We confirmed the participation of Th2-type immune reactions in Ni-induced allergy using GATA-3 Tg mice.