Staphylococcus Seed Grant Project

Staphylococcus aureus is gram-positive bacterial pathogen capable of asymptomatically colonizing about a third of the world population. This pathogen is the most common cause of nosocomial infections and a leading cause of death in hospitalized patients. The ability of S. aureus to colonize several environments is due to the presence of a variety of virulence factors that facilitate attachment, colonization, cell-cell interactions, tissue damage, dissemination through the body, and immune evasion. S. aureus infection is a frequent problem encountered by patients with Atopic Dermatitis (AD), with bacterial colonization observed on both lesional and nonlesional skin. AD, commonly known as eczema, is a complex disease. Its progression and severity depend on genetic risk factors (e.g. loss-of-function mutations in the gene encoding filaggrin), altered microbiota, and exposure to allergens. Another important factor, often neglected, is the effect of skin colonization by different strains of S. aureus, with distinct metabolic capability and pathogenicity. Although various S. aureus genomes are currently available in public repositories, the lack of information about the original source of isolation (AD skin, respiratory tract), patient clinical data, and the difficulty into obtaining available bacterial isolates, complicates strain characterization and AD contextualization. However, to accurately understand how interactions are established with the host and other bacteria and to develop targeted interventions, it is crucial to discriminate between different strains. We propose a comprehensive study to better characterize S. aureus strains from healthy people and patients with atopic dermatitis.