The so-called component-resolved immunotherapy of allergies proposes an immunization tailored to the molecular sensitization profiles of individual patients.Objectives
We sought (1) to investigate the profiles of IgE sensitization toPhleum pratensein children with grass pollen allergy and (2) to define the compatibility of these profiles with a mixture of recombinant allergenic molecules ofP pratensepreviously proposed for specific immunotherapy.METHODS
We examined 200 children (age, 4-18 years; 126 boys) with allergic rhinitis, asthma, or both ascertained through validated questionnaires. Each child underwent skin prick testing (ALK-Abelló) and serum IgE assays (ImmunoCAP, Phadia) with 9 pollen extracts. Sera reacting againstP pratensewere tested for the individual molecules (rPhl p 1, rPhl p 2, rPhl p 4, nPhl p 4, rPhl p 5b, rPhl p 6, rPhl p 7, rPhl p 11, and Phl p 12). Through a combinatorial approach, the IgE individual sensitization profiles were matched against an experimental allergen-specific immunotherapy (SIT) preparation containing Phl p 1, Phl p 2, Phl p 5, and Phl p 6.Results
Among the 176 of 200 children with IgE sensitization toP pratenseextract, 39 profiles of sensitization to the 8 allergenic molecules tested (cutoff, 0.35 kU/L) were identified. This high heterogeneity was reduced by considering only 6 or 4P pratensemolecules but not by increasing the cutoff levels of IgE positivity. The molecular profile of the experimental SIT preparation matched that of 7 (4%) of 176 patients only; the remaining 169 patients were classified in 4 mismatch categories: underpowered (29%), overpowered (32%), underpowered/overpowered (32%), and unrelated (3%).Conclusions
IgE sensitization profiles toP pratenseare highly heterogeneous. Molecularly designed SIT preparations tailored to patients’ needs should consider this high heterogeneity and be driven by locally performed population studies.