Researchers in Europe say they published a study (“Evolution and Predictive Value of IgE Responses toward a Comprehensive Panel of House Dust Mite Allergens during the First 2 Decades of Life”) in the Journal of Allergy & Clinical Immunology that identifies the molecular origins of allergy to house dust mites. The team was led by Prof. Paolo Maria Matricardi, head of the Molecular Allergology Group at the Department of Pediatric Pulmonology and Immunology of the Charité and included researchers from the Medical University of Vienna, led by Prof. Rudolf Valenta, and statisticians from Rome, Italy. The team examined the data and blood samples prospectively collected over 20 years from a cohort of 722 German children born in 1990. The children were monitored since their birth in the framework of the Multicenter Allergy Study (MAS). Purified or engineered molecules of the mite Dermatophagoides pteronyssinus were tested with nanotechnology procedures to characterize the origins and evolution of the antibody response during the children's first decades of life.

The scientists found that immunoglobulin E (IgE) antibodies against three dust mite molecules (Der p 1, Der p 2, and Der p 23) appeared early in the children's blood, often before the onset of their disease. In some (but not all) children, this first step was followed by a cascade of events involving other mite molecules through a phenomenon defined as molecular spreading. Children producing IgE to many molecules (polymolecular sensitization) had a higher risk of developing allergic rhinitis and asthma.

Earlier onset of allergic sensitization, high exposure to house dust mite allergens, and having one or both parents affected by hay fever increased the risk of polymolecular sensitization. Interestingly, healthy preschool children showing IgE antibodies to Der p 1 or Der p 23 developed asthma more frequently at school age. These and other molecules may be used for disease prevention in early life and to tailor allergen immunotherapy precisely in pediatric and adult patients, according to the scientists.

“Mite allergy develops in childhood like an avalanche. It starts early with only one or a very few molecules and then grows to many,” says Daniela Posa, first author of the publication. “The greater the spreading of molecular sensitization, the highest the risk of developing asthma.”

According to Prof. Matricardi, “Our findings open new perspectives to the use of mite allergen molecules for prediction, prevention, and therapy of allergic rhinitis and asthma caused or triggered by house dust mites.”