Effects of Tributyltin on the Development of Atopic Dermatitis-Like Eruptions in DS-Nh Mice

Background: In the last few decades, numerous chemical compounds have been produced as a result of industrial development. At the same time, the number of atopic dermatitis (AD) patients has been increasing. It has been reported that tributyltin (TBT) compounds have effects not only on the reproductive system but also on the immune system. Objective: To investigate whether TBT has an effect on AD, we fed a diet containing TBT to DS-Nh mice, which spontaneously developed dermatitis under conventional conditions. Methods: DS-Nh mice fed TBT or a control diet were examined for skin changes, number of Staphylococcus aureus on the skin and serum IgE levels. To determine Th1/Th2 cytokine production by lymphocytes, lymphocytes of DS-Nh mice fed TBT and of controls were cultured with staphylococcal enterotoxin B and cytokine levels in the supernatants were measured by ELISA. We observed not only spontaneous dermatitis but also dermatitis induced by sensitization with 2,4,6-trinitrochlorobenzene (TNCB). Results and Conclusion: The AD-like lesions induced by TNCB sensitization were more severe in the mice fed TBT than in those fed the control diet. A greater increase in S. aureus on the skin was observed in the mice fed TBT than in the mice fed the control diet. A decrease in IFN-γ production and an increase in IL-5 and IL-13 production were observed in the mice fed the TBT diet and treated with TNCB. These findings suggest that the increase in S. aureus and the enhancement of Th2 response induced by TBT exacerbate the AD-like lesions in mice treated with TNCB.