Proteomic profiling of the weed feverfew, a neglected pollen allergen source

Isabel Pablos,Claudia Asam,Barbara Bohle,Stephanie Eichhorn,Ulrike Gartner,Christof Ebner,Gabriele Gadermaier,Naveen Arora,Martin Wolf,Fatima Ferreira,Stefan Vieths,Peter Briza

doi:10.1038/s41598-017-06213-z

Abstract

Feverfew (Parthenium hysterophorus), an invasive weed from the Asteraceae family, has been reported as allergen source. Despite its relevance, knowledge of allergens is restricted to a partial sequence of a hydroxyproline-rich glycoprotein. We aimed to obtain the entire sequence for recombinant production and characterize feverfew pollen using proteomics and immunological assays. Par h 1, a defensin-proline fusion allergen was obtained by cDNA cloning and recombinantly produced in E. coli. Using two complementary proteomic strategies, a total of 258 proteins were identified in feverfew pollen among those 47 proteins belonging to allergenic families. Feverfew sensitized patients’ sera from India revealed IgE reactivity with a pectate lyase, PR-1 protein and thioredoxin in immonoblot. In ELISA, recombinant Par h 1 was recognized by 60 and 40% of Austrian and Indian sera, respectively. Inhibition assays demonstrated the presence of IgE cross-reactive Par h 1, pectate lyase, lipid-transfer protein, profilin and polcalcin in feverfew pollen. This study reveals significant data on the allergenic composition of feverfew pollen and makes recombinant Par h 1 available for cross-reactivity studies. Feverfew might become a global player in weed pollen allergy and inclusion of standardized extracts in routine allergy diagnosis is suggested in exposed populations.

Highlights

Parthenium hysterophorus is an herbaceous weed from the Asteraceae family
Sequence of Par h 1 was obtained from total feverfew pollen RNA by nested PCR with degenerated primers followed by 5′RLM-RACE protocols
The novel allergen was officially acknowledged by the Immunological Societies (IUIS) allergen nomenclature sub-committee and is listed as Par h 1.0101

Summary

Introduction

Parthenium hysterophorus is an herbaceous weed from the Asteraceae family. It is recognized with different common names like feverfew, congress grass, the “Scourge of India”, or bitter weed. In a study involving 810 rhinitis patients from Bangalore, southern India, 38% were skin prick test positive to feverfew[5], while 100 pollen allergic patients from Cuba showed a sensitization prevalence of 79% to feverfew[6]. There are observations suggesting a high risk of allergic reaction due to IgE cross-reactivity with other botanical related weeds, e.g. feverfew sensitized patients who were never exposed to ragweed showed positive skin prick tests to ragweed extract[9]. Though at present we lack epidemiologic studies on sensitization prevalence, we should be aware that the allergenicity of feverfew is likely to increase on a global basis due to climatic changes and the tremendous invasive capacity of this weed[2]. IgE immunoblot analysis and ELISA experiments were performed to investigate antibody binding and cross-reactivity with relevant allergenic molecules from mugwort and ragweed pollen

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