Paving the way of systems biology and precision medicine in allergic diseases: the MeDALL success story: Mechanisms of the Development of ALLergy; EU FP7-CP-IP; Project No: 261357; 2010-2015.

MeDALL(Mechanisms of the Development of ALLergy; EU FP7-CP-IP; Project No: 261357; 2010-2015) has proposed an innovative approach to develop early indicators for the prediction, diagnosis, prevention and targets for therapy. MeDALLhas linked epidemiological, clinical and basic research using a stepwise, large-scale and integrative approach: MeDALLdata of precisely phenotyped children followed in 14 birth cohorts spread across Europe were combined with systems biology ( omics, IgE measurement using microarrays) and environmental data. Multimorbidityin the same child is more common than expected by chance alone, suggesting that these diseases share causal mechanisms irrespective of IgE sensitization. IgE sensitization should be considered differently in monosensitized and polysensitized individuals. Allergic multimorbiditiesand IgE polysensitization are often associated with the persistence or severity of allergic diseases. Environmental exposures are relevant for the development of allergy-related diseases. To complement the population-based studies in children, MeDALLincluded mechanistic experimental animal studies and in vitro studies in humans. The integration of multimorbiditiesand polysensitization has resulted in a new classification framework of allergic diseases that could help to improve the understanding of genetic and epigenetic mechanisms of allergy as well as to better manage allergic diseases. Ethics and gender were considered. MeDALLhas deployed translational activities within the EU agenda.