Atopic dermatitis microbiomes stratify into ecologic dermotypes enabling microbial virulence and disease severity

Area of Science:

• Microbiology
• Dermatology
• Immunology

Background:

• Atopic dermatitis (AD) affects up to 20% globally, presenting significant clinical variability.
• Limited understanding exists regarding molecular subtypes and predictive biomarkers for AD.
• Baseline skin microbiome configurations and their prognostic value in AD remain underexplored.

Purpose of the Study:

• To identify microbial signatures on AD skin that can predict disease progression.
• To establish microbiome-based biomarkers for stratifying AD patients.

Main Methods:

• Whole metagenome analysis of skin microbiomes from AD patients and controls.
• Sampling of nonlesional skin at two time points.
• Immunophenotyping and analysis of skin surface factors (natural moisturizing factors, antimicrobial peptides).

Main Results:

• Two distinct microbiome configurations (dermotypes A and B) were identified and validated across cohorts.
• Dermotype B, prevalent in AD patients, showed reduced microbial richness and enrichment of pathogenic Staphylococcus species.
• Dermotype B was associated with specific metabolic pathways, virulence genes, and clinical outcomes like increased itching and disease severity.

Conclusions:

• Distinct microbial profiles (dermotypes) contribute to AD heterogeneity.
• Microbiome configurations play a role in AD pathogenesis and inflammation.
• Dermotypes offer prognostic utility for microbiome-based disease stratification in AD.