This research sheds light on the complex patterns of allergy sensitisation and their implications for medical needs, highlighting the importance of understanding molecular allergens and their role in allergies. It employed a European Health Examination Survey cohort (n=1462) of Luxembourg, deep personal sIgE profiling, and an unsupervised computational method.
Among the key findings:
- 42.6% of participants reported physician-diagnosed allergies, with 44% testing positive for IgE against at least one allergen or extract.
- Sensitisation sources were primarily tree pollens (52.4%), grass pollens (51.8%), and mites (40.3%).
- The youngest group of participants (25–34 years old) represented a significant cluster (24.4%) with multi-sensitisation to respiratory sources which reflects the highest medical needs. Poly-sensitisation, especially in younger individuals, was linked to more severe symptoms and potential increased socioeconomic costs.
- The study found that participants with respiratory allergies often exhibited sensitisation to multiple molecular allergens within the same group, indicating a high likelihood of clinical reactivity, particularly evident in complex IgE patterns for grass pollen allergens like Phl p 1, 2, 5, and 6. This phenomenon of antibody responses evolving to complex patterns, known as "molecular spreading," was linked to grass pollen allergy, starting with the initiator allergen Phl p 1 and subsequently expanding to include Phl p 4, 5, and other allergens.
- Certain initiator allergens, such as Phl p 1 and Bet v 1, played central roles in the progression of atopy (genetic predisposition to allergies).
- The study's network analysis revealed a significant interconnectedness of the PR-10 allergen cluster with many other clusters. Notably, this central role was confirmed as the PR-10 allergens were found to coexist with other allergens from another cluster rather than forming a separate isolated cluster.
- The largest cluster, including a quarter of sensitised participants, was characterised not only by allergens from the PR-10 protein family but also by sensitisation to airborne signifier allergens from other clusters, such as grass pollen allergens (Phl p 1, Lol p1, Phl p 5) and house dust mite allergens (Der p 2, Der f 2, Der p 1).
- The study's strengths included a deep population-based knowledge database and an extensive IgE panel for analysing complex IgE profiles.
- The study utilised the ALEX² Allergy Xplorer, which provided an extra 200 data points compared to the Immuno Solid-phase Allergen Chip. These additional data points were instrumental in defining IgE clusters, including specific allergens like Fag s 1, Cor a 1.0103, Fra a 1/3, Der f 2, Der p 23, Der p 7, and Gly d 2.
- Importantly, the study's molecule-resolved approach ensured comparability with other research studies, enhancing the depth and precision of their analysis.