359 Skin deep and beyond: Function of Calprotectin (S100A8/A9)

Skin diseases affect 900 million people worldwide. colonization by Staphylococcus aureus ( S. aureus) is a hallmark of Atopic Dermatitis (AD), the most common inflammatory skin disease (ISD). The expression antimicrobial peptides (AMPs) such as S100A8 (A8), S100A9 (A9) and A8/A9 heterodimer Calprotectin (CP) was reported to be elevated in ISDs, which likely influences growth. In JunBΔep genetic mouse model AD, constitutive epidermal deletion JunB leads inflammation with myeloproliferative multi-organ involvement. Here, we show increased A8, A9 CP lesional skin, serum stool mice. Hence, assess contribution these AMPs S100a9-/- compound mutants. lesions were substantially improved mice decreased colonization. However, had aggravated systemic circulating Interleukin 17A (IL-17A) high Immunoglobulin E (IgE) levels. We also observed exacerbated bone loss prominent digit swelling immune cell infiltration These results reveal complex function development ISD/AD support role inter-organ crosstalk. Ongoing experiments aim identify A8- A9-expressing cells involved ISD critical targets connected A8/A9, ultimate goal prevent or ameliorate ISD.