Skin commensal microbiota play a significant role in the pathogenesis of atopic dermatitis in both humans and dogs. While the pathogenesis of AD involves a complex interplay of genetic factors, skin barrier defects, and allergen sensitization, emerging evidence highlights the crucial role of commensal microbes in maintaining SKIN HOMEOSTASIS.
These microbes play a crucial role in modulating the immune system and defending against pathogens.
A recent study on atopic children demonstrated that a decrease in commensal microbes (dysbiosis) is linked to disruptions in the skin barrier, overgrowth of S. aureus and inflammation. Here are some key insights:
Healthy skin
In healthy skin, commensals such as coagulase-negative Staphylococcus (CoNS) and Malassezia produce compounds that inhibit the growth of S. aureus and stimulate the production of antimicrobial peptides.
Inflamed skin
Increased S. aureus colonization can stimulate increased secretion of virulence factors, leading to damage to the stratum corneum. Additionally, superantigens released by S. aureus can penetrate the epidermis, triggering pro-inflammatory cytokines.
Dogs
While canine microbiome research is limited compared to humans, findings from human studies highlight the pivotal role of commensal microbes in preserving skin homeostasis.
Reference
Tham et al. The skin microbiome in pediatric atopic dermatitis and food allergy. Allergy 2024
About the author
Dr. Aline Santana is a Brazilian veterinarian with over 12 years of experience in both research and private dermatology practice. In 2021, she completed her PhD in veterinary dermatology at the University of São Paulo (Brazil), with a sandwich period at the University of Minnesota, where she conducted research on the skin microbiome of cats. Since 2012, she has been an active member of the Brazilian Society of Veterinary Dermatology (SBDV). From 2015 to 2021, Dr. Santana served as the director of social media marketing, contributing to the organization's outreach and communication efforts.
