ADF/ECARF Award 2018: The role of skin bacteria in atomic dermatitis and why diabetics are less prone to contact allergies

This year’s ADF/ECARF Award has been granted to two teams studying the interactions that occur within inflammatory skin diseases. In their award-winning study1, Dr Hansjörg Baurecht and his team of scientists from the University Medical Center Schleswig-Holstein describe the changes that occur in the bacterial colonies of the skin in people with atopic dermatitis. The research team of Dr Talkea Schmidt of the Mainz University Medical Center studied the effects of type 1 diabetes on allergic contact dermatitis2. The prize, endowed with €5,000, was presented at the 45th annual ADF Meeting (Arbeitsgemeinschaft Dermatologische Forschung – working group for dermatological research) in Zurich, Switzerland on 9 March.

The award-winners ADF/ECARF 2018: Dr. rer. nat. Hansjörg Baurecht (2.v.l.), Dr. rer. nat. Talkea Schmidt (3.v.l)

The skin microbiome – the community of all the microorganisms on the skin – has a different composition in people with atopic dermatitis and is less diverse than in people with healthy skin. This had already been observed in areas of the body typically affected by the disease, such as the creases in the arms or the back of the knees. The researchers in Kiehl successfully proved that, in people with atopic dermatitis, the microbiome is also altered on unaffected areas of the skin. As the skin progresses from healthy to dry and then to inflamed, the diversity of the bacteria and the amount of certain staphylococci decreases successively, while certain other strains increase, in particular S. aureus”, said Dr Hansjörg Baurecht. “The inflammation causes massive changes in the skin, regardless of the body area. The extent to which this occurs was unexpected.”

According to Professor Torsten Zuberbier, Director of the European Centre for Allergy Research Foundation (ECARF) and chairman of the jury, the study contributes to a better understanding of the interaction between the microbiome and skin function. He believes that the work is “important basic research for new therapies that may have an influence on the skin microbiome. The entire field is very exciting. We already know a lot from gastrointestinal research about health-promoting microorganisms such as lactobacilli and how they can be altered with food. In a similar way, special creams could be used to promote the ‘good’ bacteria on the skin.”

The award-winning research from the Mainz team also offers new insights. “The study provides additional findings about the link between allergies and autoimmune diseases,” said the chairman of the jury. Epidemiological studies have shown that people with autoimmune diseases, such as type 1 diabetes, psoriasis or rheumatoid arthritis, are less prone than healthy people to developing allergic contact dermatitis. Dr Schmidt’s team of researchers investigated these observations by examining the corresponding immune processes in animal models. To do this, they triggered a contact hypersensitivity reaction to a contact allergen in mice with diabetes by applying the sensitising substance to the ears of the animals. The scientists were able to demonstrate that the skin of the diabetic mice had a lower inflammatory response (less swelling, fewer inflammatory infiltrates) than the skin of the non-diabetic mice. They also proved that interleukin 10, a messenger substance, played a significant role in this process. The diabetic mice with less inflammation had higher levels of interleukin 10 than the control group with higher levels of inflammation. When interleukin 10 was blocked in the diabetic mice, inflammation increased.

The researchers hope that their work will aid in the development of better treatments for immune-mediated inflammatory diseases in future.

 

(1) Baurecht H, Rühlemann MC, Rodríguez E, Thielking F, Harder I, Erkens AS, Stölzl D, Ellinghaus E, Hotze M, Lieb W, Wang S, Heinsen FA, Franke A und Weidinger S (2018): Epidermal lipid composition, barrier integrity and eczematous inflammation are associated with skin microbiome configuration. Journal of Allergy and Clinical Immunology, https://doi.org/10.1016/j.jaci.2018.01.019
(2) Schmidt T, Lorenz N, Raker VK, Steinbrink K: How autoimmunity fights with allergy: Impaired development of allergic contact dermatitis in type I diabetic mice (unveröffentlichte Studie)