782 Fucosyltransferase 1 plays a protective role in the development of atopic dermatitis-like disease in mice

Epidermal surface lipids, mostly ceramides, cholesterol, and fatty acids play an essential role in skin barrier function. The abnormalities of epidermal lipids were observed in patients with atopic dermatitis (AD). In our previous study, we showed that epidermal fucosylation was abnormal in patients with AD, compared with healthy control subjects. However, the biological function of α(1,2)–fucosylation by fucosyltransferase 1 (Fut1) in skin remains mostly unknown. Here, we found that Fut1-deficient mice had lower levels of epidermal lipids, compared to WT mice, suggesting that α(1,2)–fucosylation may be involved in the regulation of epidermal lipid compositions. Furthermore, using a MC903-induced AD-like mouse model, Fut1-deficient mice showed higher serum IgE levels, compared to WT mice. The production of AD-associated cytokines such as interleukin-4 (IL-4) and IL-6 in skin lesions was significantly higher in Fut1-deficient mice than in WT mice. MC903-induced epidermal and dermal thickening were greater in Fut1-deficient mice compared to WT mice. Infiltration of CD4+ T cells, Gr-1+cells (neutrophils), and mast cells into lesion skin was significantly higher in Fut1-deficient mice than in WT mice. Thus, these findings reveal that barrier dysfunction in α(1,2)–fucosylation-deficient skin may be related with the severity of atopic dermatitis.