The IgE repertoire in children and adolescents resolved at component level: a cross-sectional study

It is well known that allergy evolves at clinical level from the birth to adulthood, and this has been clearly demonstrated also at a level of sensitization. However, little information is available on the evolution of the IgE repertoire directed to single allergenic components. In this cross-sectional, observational study, the evolution of the IgE repertoire was analysed at component level.

Serum samples from 901 allergic patients, stratified in 6 groups according to age, were analysed by ImmunoCAP ISAC, a microarray chip that allows to identify the presence of specific IgE towards 103 different allergen components. Total IgE were also evaluated.

The behaviour of total IgE according to age strictly paralleled that of the sum of specific IgE directed to molecular components. As expected, food-related components (in particular those of milk and egg) were the most frequently recognized in the earliest ages, whereas specific IgE to plant allergens appeared invariably later. Nonetheless, IgE specific to mite components was the most represented in all age classes. Of note, specific IgE against cross-reacting allergens was virtually absent in the first years and tended to appear only after the age of 6.

Despite this was not a study performed on a cohort of patients followed up from birth to adolescence, the molecular patterns of allergen recognition resulted modified according to age. These findings may support, at molecular level, the clinical features of the allergic march.