Multi-omics analyses reveal host-microbe interactions in atopic dermatitis and psoriasis

Area of Science:

• Dermatology
• Microbiome Research
• Immunology

Background:

• Atopic dermatitis (AD) and psoriasis (PSO) are chronic inflammatory skin diseases with significant patient burden.
• The role of the skin mycobiome and its interplay with bacteria and host immunity in AD and PSO is not well understood.

Purpose of the Study:

• To characterize the skin mycobiome in AD and PSO.
• To investigate the interactions between fungal and bacterial communities.
• To explore the relationship between the skin microbiome and host immune responses in AD and PSO.

Main Methods:

• Whole-metagenome shotgun sequencing was employed to profile microbial communities in skin samples from AD, PSO patients, and healthy controls.
• Fungal-bacterial co-occurrence networks were constructed using SparCC.
• Integration of host transcriptomic and microbial data was performed using O2PLS.

Main Results:

• Both AD and PSO exhibited altered Malassezia species composition and reduced fungal-bacterial connectivity in lesional skin.
• In AD, Malassezia arunalokei showed inverse correlation with Staphylococcus aureus and was linked to IL-17 signaling pathways, with decreased abundance correlating with disease severity.
• In PSO, altered Malassezia composition was associated with IL-17-driven inflammation and lipid metabolism.

Conclusions:

• Disrupted fungal-bacterial interactions in the skin microbiome contribute to immune activation in AD and PSO.
• Skin microbiome alterations, particularly fungal dysbiosis, are linked to disease severity in AD.
• These findings suggest potential for microbiome-based diagnostics and therapeutics for AD and PSO.