Date Published: 23 September 2005
Structural study will help develop new asthma and allergy treatments
The structure of a molecule that regulates levels of the key antibody involved in allergic reactions and asthma, IgE, has been revealed by researchers from Oxford University and King's College London. The study, published in Journal of Experimental Medicine, is expected to help in the developmemt of drugs to treat these two conditions.
IgE is thought to make certain cells of the immune system (mast cells) more sensitive to allergens, so lowering circulating levels of active IgE is a possible way of reducing the symptoms of allergies or allergic asthma.
The low-affinity receptor for IgE, called CD23, plays a dual role in the production of IgE. It can either inhibit or stimulate the antibody's production, depending whether it is attached or detached from the cell membrane.
Small molecules that bind to CD23 and prevent it from stimulating IgE production could be potential allergy and asthma treatments.
The researchers at Oxford and King's used nuclear magnetic resonance (NMR) spectroscopy to discover the structure of CD23. They also identified which parts of the molecule are used in the promotion of IgE production ? and therefore which regions inhibitors could bind to stop this process.
Professor Brian Sutton from King's, a co-researcher on the study, said:
" Currently a therapy that blocks IgE functioning is available, but it is expensive. Drugs that prevent the production of IgE might be a much cheaper way of treating allergies. We hope that this study will provide a structural basis for the development of such inhibitors."
Dr James McDonnell of Oxford's Department of Biochemistry, who led the study, said:
" This is an important step forward in understanding some of the underlying mechanisms of the allergic response. Our next challenge is to develop the therapeutic potential of this information"
Asthma UK funded part of the work. Dr Lyn Smurthwaite, their Research Development Manager said:
" The development of new therapies for people with asthma is an important part of Asthma UK's research programme. We welcomed the opportunity to be involved with this study and look forward to further advances that may be used to prevent the initiation of the allergic asthmatic response."
Main source: Oxford University, England (UK)