Polybia paulista (Hymenoptera: Vespidae) is responsible for a high number of sting accidents and anaphylaxis events in Southeast Brazil, Argentina and Paraguay. The specific detection of allergy to the venom of this wasp is often hampered by the lack of recombinant allergens currently available for molecular diagnosis. Antigen 5 (~23 kDa) from P. paulista venom (Poly p 5) is a highly abundant and glycosylated allergenic protein that could be used for development of component-resolved diagnosis (CRD). Here, we describe the cloning and heterologous expression of the antigen 5 (rPoly p 5) from P. paulista venom using the eukaryotic system Pichia pastoris. The expression as a secreted protein yielded high levels of soluble rPoly p 5. The recombinant allergen was further purified to homogeneity (99%) using a two-step chromatographic procedure. Simultaneously, the native form of the allergen (nPoly p 5) was purified from the wasp venom by Ion exchange chromatography. The rPoly p 5 and nPoly p 5 were then submitted to a comparative analysis of IgE-mediated immunodetection using sera from patients previously diagnosed with sensitization to wasp venoms. Both rPoly p 5 and nPoly p 5 were recognized by specific IgE (sIgE) in the sera of the allergic individuals. The high levels of identity found between nPoly p 5 and rPoly p 5 by the alignment of its primary sequences as well as by 3-D models support the results obtained in the immunoblot. Overall, we showed that P. pastoris is a suitable system for production of soluble rPoly p 5 and that the recombinant allergen represents a potential candidate for molecular diagnosis of P.paulista venom allergy.

Purpose of Review: In Hymenoptera venom allergy, the research focus has moved from whole venoms to individual allergenic molecules. Api m 10 (icarapin) has been described as a major allergen of honeybee venom (HBV) with potentially high relevance for diagnostics and therapy of venom allergy. Here, we review recent studies on Api m 10 characteristics as well as its role in component-resolved diagnostics and potential implications for venom-specific immunotherapy (VIT). Recent Findings: Api m 10 is a major allergen of low abundance in HBV. It is an obviously unstable protein of unknown function that exhibits homologs in other insect species. Despite its low abundance in HBV, 35 to 72% of HBV-allergic patients show relevant sensitization to this allergen. Api m 10 is a marker allergen for HBV sensitization, which in many cases can help to identify primary sensitization to HBV and, hence, to discriminate between genuine sensitization and cross-reactivity. Moreover, Api m 10 might support personalized risk stratification in VIT, as dominant sensitization to Api m 10 has been identified as risk factor for treatment failure. This might be of particular importance since Api m 10 is strongly underrepresented in some therapeutic preparations commonly used for VIT. Summary: Although the role of Api m 10 in HBV allergy and tolerance induction during VIT is not fully understood, it certainly is a useful tool to unravel primary sensitization and individual sensitization profiles in component-resolved diagnostics (CRD). Moreover, a potential of Api m 10 to contribute to personalized treatment strategies in HBV allergy is emerging.