Hymenoptera allergens: from venom to "venome"

Abstract

In Western Europe, Hymenoptera venom allergy (HVA) primarily relates to venoms of the honeybee and the common yellow jacket. In contrast to other allergen sources, only a few major components of Hymenoptera venoms had been characterized until recently. Improved expression systems and proteomic detection strategies have allowed the identification and characterization of a wide range of additional allergens. The field of HVA research has moved rapidly from focusing on venom extract and single major allergens to a molecular understanding of the entire "venome" as a system of unique and characteristic components. An increasing number of such components has been identified, characterized regarding function, and assessed for allergenic potential. Moreover, advanced expression strategies for recombinant production of venom allergens allow selective modification of molecules and provide insight into different types of immunoglobulin E reactivities and sensitization patterns. The obtained information contributes to an increased diagnostic precision in HVA and may serve for monitoring, re-evaluation, and improvement of current therapeutic strategies.

Keywords: allergen components; allergy; cross-reactivity; insect venom; recombinant allergens; sensitization.

Figure 1

Venom components and CCD. (A) Representative 2D-gel of the honeybee venom stained with Coomassie Brilliant Blue G-250 demonstrating the complexity of the venome (kindly provided by Dr. Nico Peiren, Laboratory of Zoophysiology, Ghent University, Belgium). (B) CCD sIgE-reactivity of rabbit anti-HRP serum with different Hymenoptera venoms in immunoblotting. Note the lack of CCD-reactivity in Polistes venom. (C) Schematic representation of xenobiotic core glycosylation as found in insects. This carries an additional α 1,3-linked fucose residue compared to plants having an additional β 1,2-linked xylose residue. (GlcNAc, N-acetylglucosamine; Man, mannose; Fuc, fucose). (D) Comparison of IgE antibody levels to glycosylated rApi m 1 (CG) and native purified Api m 1 in CCD negative HBV allergic patients (n = 89). Hatched horizontal and vertical lines indicate the 0.35 kUA/L cut-off and the hatched diagonal line represents a 1:1 ratio.