Step Up Skin Microbiome Understanding to Advance AD Treatment

Multiple factors such as physiology, environment, immune system, genotype, lifestyle, and pathobiology contribute to a person’s skin microbiota. Lawrence J. Green, MD, FAAD, a clinical professor of dermatology at the George Washington University School of Medicine in Washington D.C. offered an in depth exploration of the relationship between the skin microbiome and barrier function at the 2021 Fall Clinical Dermatology Conference being held October 21 to 24, 2021 in Las Vegas, Nevada, and virtually.¹ 

The interaction between skin commensals and barrier function of the skin can result in inflammation. That puts added importance on the role of the skin barrier since it prevents harmful substances from penetrating the stratum corneum, Green explained.

He pointed to study results² that showed the higher proportion of staphylococcus (with the greatest of S. Aureus) was correlated with worse atopic dermatitis (AD) flares. It was also demonstrated that AD flares are associated with lower the skin bacterial diversity. 

Skin that is affected by AD and unaffected by AD have different microbiomes, Green said. There is more staphylococcus on the skin of patients with AD. However, both have an abundance of firmicutes³. 

Green identified 4 agents that could help rebalance the micrbiome^4,5:

• Water
• Carbon sources
• Nitrogen sources
• Oligoelements

Prebiotics and postbiotics are nonliving agents that stimulate the growth of indigenous bacteria, which may help with flare ups according to Green. He noted that roseomonas mucosa was identified as the most common gram-negative skin organism in individuals without AD, but mostly absent in AD patients.^5,6

He highlighted the fact that strains of roseomonas mucosa can induct the Vitamin D pathway markers and may contribute to the suppression of staphylococcus (including MRSA). According to Green, this means the colonization of roseomonas mucosa to the skin may help as a probiotic for AD. 

He noted that La Roche-Posay Thermal Spring Water [LRP-TSW] can significantly reduce the disease severity of AD and staphylococcus genus while increasing the level of Xanthomonas genus⁷. The study found that an emollient in this prepared product with a high concentration of LRP-TSW has demonstrated positive impact on the microbiome of AD patients associated with longer time between AD flare ups when compared to a competitive emollient-prebiotic, according to Green⁷.

Understanding the skin microbiome may help physicians better treat AD patients, Green concluded. 

Disclosures:

Lawrence J. Green, MD, FAAD, is an investigator and advisor for Arcutis Biotherapeutics, Dermavant Sciences, Forte, and LaRoche-Posay.

Reference:

1. Green L. Considering the Skin Microbiome in the Management of Barrier Repair & Atopic Dermatitis. Presented at: 2021 Fall Clinical Dermatology Conference, October 21 to 24, 2021 in Las Vegas, Nevada and virtual. 
2. Kong HH, Oh J, Deming C, et al. Temporal shifts in the skin microbiome associated with disease flares and treatment in children with atopic dermatitis. Genome Res. 2012;22(5):850-859. doi:10.1101/gr.131029.111
3. Conners SB, Mongodin EF, Johnson MR, Montero CI, Nelson KE, Kelly RM. Microbial biochemistry, physiology, and biotechnology of hyperthermophilic Thermotoga species. FEMS Microbiology Reviews. 2006;30(6):872-905. doi:10.1111/j.1574-6976.2006.00039.x
4. Wackett LP, Dodge AG, Ellis LBM. Microbial genomics and the periodic table. Appl Environ Microbiol. 2004;70(2):647-655. doi:10.1128/AEM.70.2.647-655.2004
5. Myles IA, Williams KW, Reckhow JD, et al. Transplantation of human skin microbiota in models of atopic dermatitis. JCI Insight. 2016;1(10). doi:10.1172/jci.insight.86955
6. Li M, Hener P, Zhang Z, Kato S, Metzger D, Chambon P. Topical vitamin D3 and low-calcemic analogs induce thymic stromal lymphopoietin in mouse keratinocytes and trigger an atopic dermatitis. Proc Natl Acad Sci USA. 2006;103(31):11736-11741. doi:10.1073/pnas.0604575103
7. Seite S, Flores GE, Henley JB, et al. Microbiome of affected and unaffected skin of patients with atopic dermatitis before and after emollient treatment. J Drugs Dermatol. 2014;13(11):1365-1372.