Prevalence of IgE-Binding to Art v 1, Art v 4 and Amb a 1 in Mugwort-Allergic Patients

Abstract

Background: Mugwort (Artemisia vulgaris) represents an important source of weed pollen allergens. The objectives of the present study were (i) to analyze the IgE binding profiles in a group of mugwort-allergic patients, (ii) to identify individual marker allergens crucial for the diagnosis of mugwort allergy and (iii) to identify potential crossreactive allergens present in ragweed (Ambrosia artemisiifolia) pollen extract. Methods: Sera from 100 pediatric mugwort-allergic patients were analyzed for their IgE binding pattern to natural mugwort and ragweed pollen proteins, purified natural and recombinant Art v 1, recombinant Art v 4 and recombinant Amb a 1 using immunoblots and ELISA. Results: 91% of the patients’ sera tested displayed IgE binding to one or more mugwort pollen allergens in ELISA and 88% were positive in immunoblot. Purified natural Art v 1 was recognized by 79%, the recombinant protein by 39% of the patients tested and purified recombinant Art v 4 by 34% of the patients’ sera. 67% of the sera displayed crossreactive IgE to one or more ragweed pollen allergens. Recombinant Amb a 1 was noted in only 14% of the mugwort-allergic sera. Conclusions: Allergen-specific in vitro diagnosis was performed in 100 pediatric mugwort-allergic serum samples. Using two allergens (Art v 1 and Art v 4), 91% of the patients could be identified as mugwort pollen-sensitized patients by IgE in vitro tests. Crossreactivity to ragweed pollen allergens was demonstrated by in vitro experiments, suggesting a new important and potent allergen source expanding across Europe.

Structural, Functional, and Immunological Characterization of Profilin Panallergens Amb a 8, Art v 4, and Bet v 2

“…This is consistent with epidemiological studies that indicate that only a single allergenic source, probably that providing the highest profilin exposure, may be responsible for triggering IgE response to profilins (23). Moreover, IgE cross-reactivity to ragweed allergen Amb a 1 of sera derived from mugwort allergic patients living in the area with no ragweed exposure has been reported (46). In summary, our study provides evidence for the existence of a specific IgE response to well characterized profilins Art v 4 and Amb a 8 and demonstrates the differences in IgE binding between weed profilins and tree profilins, which are related to the structural differences of those proteins.…”

“…The recombinant profilins were recognized by IgE from some allergic patients, which is consistent with previous reports (21,27,45,46). Several studies have demonstrated that IgE from patients sensitized to one profilin binds to profilins from all other sources (40,41).…”

Mugwort-Sensitized Individuals from North Europe, South Europe and North America Show Different IgE Reactivity Patterns

“…However, no information about sensitization to whole mugwort pollen extract was given [8]. The prevalence of IgE reactivity to Art v 1 of 84% in mugwort-sensitized subjects from North Europe found in the present study is similar to the prevalence of 79% recently reported for mugwort-allergic subjects in Germany [22]. In the German study, 14% of the subjects were sensitized to Amb a 1; this percentage is also similar to the corresponding prevalence figures obtained for the European subjects in our study.…”

A Molecular Diagnostic Algorithm to Guide Pollen Immunotherapy in Southern Europe: Towards Component-Resolved Management of Allergic Diseases

“…On the other hand, nArt v 1 is considered a true major mugwort pollen allergen, accounting for IgE-sensitization in approximately 80% of mugwort-pollen-allergic patients [59,60]. Importantly, it is an effective marker of genuine sensitization to mugwort pollen, even when cross-reactivity to minor ragweed allergen Amb v 4 occurs [61].…”