Validation of the Short-term Antimicrobial Action of Transplanted Bacteria

Unlike healthy control skin, the skin of patients with atopic dermatitis (AD) is frequently colonized by Staphylococcus aureus (S. aureus), putting these patients at increased risk of S. aureus skin infections. In addition, research in the investigator's lab has shown that these patients have fewer protective antimicrobial Staphylococcal species such as Staphylococcal epidermidis (S. epidermidis) that are known to produce antimicrobial peptides that play a role in protecting the skin from invading pathogens. In this study, the investigator will attempt to decrease S. aureus colonization and increase colonization by protective Staph species in AD patients. First the investigator will capture the bacteria on subjects' lesional AD skin. Next the investigator will selectively grow the subject's antimicrobial Staphylococcal colonies and place them into a base moisturizer. The moisturizer plus bacteria will be applied to one of the subject's arms, and the moisturizer alone (without bacteria) to the other arm. The investigator will then do a quantitative wash of the bacteria growing on each arm one day later in order to determine whether the S. aureus abundance was affected by the application of the transplanted bacteria.