IL-25 target for asthma attacks caused by colds

A small molecule called interleukin-25 might play a central role in asthma attacks brought on by the common cold. The cytokine has been implicated in a sequence of biological events triggered by rhinoviruses – the predominant cause for the common cold – which could cause these life-threatening attacks. Interleukin-25 (IL-25) is induced by rhinovirus infection, instigating the production of other type-2 cytokines, driving the type-2 immune response – inflammation of the airways and increased mucus production. Scientists compared cells from the lungs of asthmatics to cells from healthy volunteers, finding that when infected with a rhinovirus, asthmatic lung cells produce around 10-fold higher levels of IL-25. Nasal secretions from asthmatics infected with a rhinovirus had a higher level of IL-25 than infected healthy volunteers. "Our research has shown for the first time that the cells that line the airways of asthmatics are more prone to producing a small molecule called IL-25, which then appears to trigger a chain of events that causes attacks,” said Dr Nathan Bartlett, Honorary Lecturer at the National Heart and Lung Institute, Imperial College London. “By targeting this molecule at the top of the cascade, we could potentially discover a much-needed new treatment to control this potentially life-threatening reaction in asthma sufferers." Recent trials have shown that antibodies that block individual type-2 cytokines have modest therapeutic effects. “The next steps are to test blocking IL-25 in humans, and to investigate other possible pathways that could be important in asthma attacks and pool this knowledge to develop effective treatments,” said Professor Sebastian Johnson from the National Heart and Lung Institute. The work, which included researchers at King’s College London, has been published in Science Translational Medicine. Rhinovirus induced IL-25 asthma exacerbation drives type-2 immunity and allergic pulmonary inflammation