In 2019, SILAB established a research partnership with Dr Richard Gallo, an expert on skin microbiota in San Diego (UCSD), to improve understanding of the role of skin microbiota in the inflammatory process characteristic of compromised skin.
This work has been the subject of two publications in the prestigious scientific journals Cell Reports and The Journal of Allergy and Clinical Immunology. The involvement of skin microbiota, in particular opportunistic pathogenic bacteria such as Staphylococcus aureus (S. aureus), in skin diseases is now well established. More recently, studies reported an overrepresentation of the species Staphylococcus epidermidis (S. epidermidis) on compromised lesional skin.
This common commensal bacterium of the healthy skin microbiota with benefits for the host may be involved in the compromised skin phenotype. The objective of the work carried out in Dr Gallo’s team was to identify the role and mechanism of action of S. aureus and S. epidermidis in the pathogenesis of two inflammatory skin diseases: Netherton syndrome and atopic dermatitis. The results supported the existence of a pathogenic role for S. epidermidis in compromised skin, similar to S. aureus. The deleterious effects of these two species result from an interspecies communication through a sophisticated system known as quorum sensing. This system allows synchronisation of proteases secretion specific of each bacterial population. These virulence factors exacerbate the alterations in epidermal barrier function and inflammatory phenomenon characteristic of Netherton syndrome and atopic dermatitis.
Laura Cau, who was involved in the project at UCSD as part of scientific international volunteering funded by SILAB, explains: “These discoveries highlight the considerable influence of the interspecies communication within the epidermal ecosystem on skin health. They strengthen the understanding of the role of commensal microbiota in the development of inflammatory skin diseases”.