Answers for Atopic Dermatitis and Allergies: What is the Role of the Skin Bacteriome?

Atopic Dermatitis (AD) is a chronic inflammatory skin condition marked by skin barrier dysfunction and immune dysregulation. Influenced by genetic, immunological and environmental factors, as well as the skin microbiome, AD often occurs alongside food allergies (FA). Research has investigated how the skin microbiome contributes to this.

What We Know:

• The 'Dual Allergen Exposure Hypothesis' posits that dermal exposure to allergens during the early life period can lead to FA development, whereas early consumption of allergenic foods promotes tolerance (Lack et al., 2003).

• During AD flare-ups, the skin microbiome composition changes: microbial diversity decreases as disease severity increases and generally the abundance of Staphylococcus aureus significantly rises. Approximately 70% of AD individuals are colonised with S. aureus on lesional skin and 30%–40% in non-lesional skin. Staphylococcus epidermidis communities are present in both flare and post-flare states (Totté et al., 2016).

Industry Impact and Potential:

• Mouse studies have shown that FA can develop through skin exposure to allergens due to compromised skin barriers in AD. This involves immune cell activation, increased allergen-specific antibodies and inflammation. Exposure to staphylococcal toxin (SEB) and allergens results in stronger allergic responses than exposure to allergens alone, suggesting that SEB may enhance food allergy development through AD-affected skin (Savinko et al., 2005).

• AD children colonised by S. aureus have a higher risk of FA compared to healthy controls. Infants aged 4-60 months colonised by S. aureus have an increased risk of developing peanut and egg allergies within their first 5 years, regardless of AD severity (Jones, Curran-Everett & Leung, 2016; Tsilochristou et al., 2019). 

• A deeper understanding of how the skin barrier and microbiome contribute to the development of AD and FA has sparked interest in skin-based interventions for allergy prevention. Several randomised controlled trials have examined prophylactic skin interventions from infancy to prevent AD, yielding mixed results. Future research should investigate how early-life shifts in skin microbiota affect AD and FA onset to refine intervention strategies and identify microbial biomarkers for high-risk infants. Although using skin microbes as biotherapeutics for AD shows promise, further investigation is needed to assess its potential for sustained clinical benefits  (Tham et al., 2024).

Our Solution:

At Sequential, we specialise in comprehensive Microbiome Product Testing tailored to meet your specific goals in formulating products, such as AD and FD treatment and prevention strategies. Our customised services empower businesses to confidently develop topical solutions. We facilitate microbiome studies to ensure these products maintain microbiome integrity, promoting efficacy and compatibility for healthier skin. 

References:

Jones, A.L., Curran-Everett, D. & Leung, D.Y.M. (2016) Food allergy is associated with Staphylococcus aureus colonization in children with atopic dermatitis. Journal of Allergy and Clinical Immunology. 137 (4), 1247-1248.e3. doi:10.1016/j.jaci.2016.01.010.

Lack, G., Fox, D., Northstone, K. & Golding, J. (2003) Factors Associated with the Development of Peanut Allergy in Childhood. New England Journal of Medicine. 348 (11), 977–985. doi:10.1056/NEJMoa013536.

Savinko, T., Lauerma, A., Lehtimäki, S., Gombert, M., Majuri, M.-L., Fyhrquist-Vanni, N., Dieu-Nosjean, M.-C., Kemeny, L., Wolff, H., Homey, B. & Alenius, H. (2005) Topical Superantigen Exposure Induces Epidermal Accumulation of CD8+ T Cells, a Mixed Th1/Th2-Type Dermatitis and Vigorous Production of IgE Antibodies in the Murine Model of Atopic Dermatitis1. The Journal of Immunology. 175 (12), 8320–8326. doi:10.4049/jimmunol.175.12.8320.

Tham, E.H., Chia, M., Riggioni, C., Nagarajan, N., Common, J.E.A. & Kong, H.H. (2024) The skin microbiome in pediatric atopic dermatitis and food allergy. Allergy. 79 (6), 1470–1484. doi:10.1111/all.16044.

Totté, J.E.E., van der Feltz, W.T., Hennekam, M., van Belkum, A., van Zuuren, E.J. & Pasmans, S.G.M.A. (2016) Prevalence and odds of Staphylococcus aureus carriage in atopic dermatitis: a systematic review and meta‐analysis. British Journal of Dermatology. 175 (4), 687–695. doi:10.1111/bjd.14566.

Tsilochristou, O., Toit, G. du, Sayre, P.H., Roberts, G., Lawson, K., et al. (2019) Association of Staphylococcus aureus colonization with food allergy occurs independently of eczema severity. Journal of Allergy and Clinical Immunology. 144 (2), 494–503. doi:10.1016/j.jaci.2019.04.025.