A recent study by a team of scientists at the WIMM, led by Professor Graham Ogg and in collaboration with Professor Branch Moody in Harvard, have identified that a protein within bee and wasp venom activates a new pathway of inflammation in the skin.
Honey beeThe protein is an enzyme called phospholipase which causes damage in the skin by breaking down the membranes of cells in to their constituent lipid parts (or fats). The lipids are then recognised by the immune system as a sign of danger, leading to a rapid immune defence response and skin inflammation.
What is particularly intriguing is that this pathway may be part of a broader system of how we detect breaches in the barrier of the skin. The body must have good ways to detect when skin barrier is compromised, so that it can respond appropriately to clear microbes and start the process of repair and healing.
By sensing the lipid products of damaged cell membranes, the immune system can detect when skin cells have been destroyed, and then mobilise other parts of the response as required. For example, it may that the barrier breach is accompanied by a local bacterial infection of the skin which will need to be recognised and cleared by the relevant cells of the immune system which are dedicated to carrying out this task.
By understanding how the body detects breaches in the skin, the work is likely to provide insights in to other skin diseases in which we know there is skin barrier compromise.
Ruby tailed waspThis type of damage to the skin is often found in a range of diseases including eczema, one of the most common skin diseases in the UK, which is also linked with asthma, hay fever and food allergies. Many patients with eczema have impaired barrier function of the skin which is thought to lead to entry of irritants, infections and airborne allergens, resulting in often long-term and distressing skin symptoms.
A further interesting question is how the bees and wasps protect themselves from the damaging effects of the phospholipase within their own sting venom. It is likely that there are inhibitor systems in the venom which can temporarily inactivate the phospholipase until it has been injected into the unfortunate victim.
Graham Ogg’s team is aiming to understand these control systems in order to develop new approaches to treat different types of inflammation associated with skin barrier compromise. Therefore as well as providing essential roles in our environment, bees also have the capacity to teach us about our own immune system.
It is hoped that the findings of the current work, which were published in the Journal of Experimental Medicine in February 2015 (volume 212, p149-63), will eventually lead to better understanding and treatments of allergies, eczema and other skin diseases.
Post edited by Bryony Graham.
The Ogg lab are grateful for funding from the MRC, Misses Barrie Charitable Trust, and the British Skin Foundation.
Many thanks also to the Wellcome Trust for the images provided under Creative Commons license http://creativecommons.org/licenses/by-nc-nd/4.0/