180 The antimicrobial peptide derived from insulin-like growth factor-binding protein 5 promotes skin barrier function and relieves dermatitis-like symptoms in a mouse model of atopic dermatitis

The antimicrobial peptide derived from insulin-like growth factor-binding protein 5 (AMP-IBP5) displays antimicrobialactivities and immunomodulatory properties; however, its role in the regulation of skin barrier context atopic dermatitis (AD) remains unclear. Normal human keratinocytes were stimulated with AMP-IBP5 Western blot was used to analyze expression tight junction (TJ)-related proteins. Immunofluorescence staining examine intercellular distribution TJ-related Activation signaling pathways aPKC Rac1 evaluated by TJ function investigated measurement transepithelial electrical resistance (TER). BALB/c mice treated 2,4-dinitrochlorobenzene as AD mouse model. permeability assay immunofluorescence investigate vivo mice. We found that increased various proteins, including claudin-1, occludin zonula occludens 1 enhanced their along cell-cell borders. also improved shown increasing TER keratinocyte. In addition, phosphorylation Rac1, which are required for AMP-IBP5-mediated improvement barrier, evidenced inhibitory effects respective inhibitors on TER. mice, symptoms, recovered proteins function. Additionally, suppressed production inflammatory cytokines such IL-4, IL-13, IL-31, IL-33 TSLP. finding relieves symptoms enhances indicates a possible application treatment AD.