Amelioration of the progression of an atopic dermatitis-like skin lesion by silk peptide and identification of functional peptides.

The efficacy of silk peptide in treatment of atopic dermatitis was examined in a picryl chloride-induced atopic dermatitis model in NC/Nga mice. Silk peptide ameliorated the development of atopic dermatitis by lowering the serum IgE concentration. Treatment of cultured spleen cells with silk peptide reduced IgE production by enhancing the production of IFN-γ and reducing the level of IL-4. The functional peptides in the silk peptide were identified as mixture of GAGA sequences containing peptides by mass spectrometry and in vitro assay. Our findings indicate that silk peptide exerts an effect on atopic dermatitis by modulating the Th1/Th2 balance.