860 Microbiome therapy of atopic dermatitis by application of rationally selected human commensal skin bacteria

Disease severity in atopic dermatitis (AD) is negatively influenced by S. aureus (SA). SA can be inhibited by antimicrobial molecules made by some strains of coagulase-negative Staphylococcus (AM+CoNS). A lack of AM+CoNS correlates with SA abundance and disease severity in AD. A previous clinical trial showed autologous AM+CoNS could reduce SA on AD skin within 24 hrs. Recently, some CoNS were also found to inhibit expression of SA toxins by blocking quorum sensing through production of autoinducing peptides (AIPs). For this reason, a single strain of S. hominis(SHA9) that produces both AMs and an AIPwas selected for further testing of safety and potential therapeutic efficacy in mice and humans. Application ofSHA9 to OVA-sensitized Balb/c FLGft/ftmice reduced SA survival by >99% (P