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Notes: Background The T cell reactivity to the major allergen of bee venom, phospholipase A2, has been thoroughly characterized. In contrast, only little is known about the human cellular response to major allergens from wasp venom.Objective To characterize the human T cell response to antigen 5 from Vespula vulgaris, Ves v 5.Methods Recombinant Ves v 5 was used to establish allergen-specific T cell lines (TCL) and T cell clones (TCC) from the peripheral blood of vespid-allergic and non-allergic individuals. Ves v 5-specific TCL were mapped for T cell epitopes using overlapping synthetic peptides representing the complete amino acid sequence of Ves v 5. Ves v 5-specific TCC were analysed for antigen-induced secretion of IL-4, IFN-γ and IL-10.Results Seventeen distinct T cell epitopes were recognized by allergic individuals among which Ves v 5181–192 was identified as a dominant T cell epitope. Partially different epitopes were observed in TCL from non-allergic subjects and the dominant epitope Ves v 5181–192 was not prevalent in these cultures. Ves v 5-specific TCC isolated from allergic individuals did not show the typical T helper type 2 (Th2)-like cytokine profile in response to specific stimulation, i.e. high amounts of IL-4 and low IFN-γ. TCC from non-allergic individuals showed a Th1-like cytokine pattern.Conclusions Our findings provide evidence that the allergic T cell response to Ves v 5 is not Th2-dominated and that different immunogenic sites on this major wasp venom allergen are recognized by allergic and non-allergic individuals.

Notes: Background Patients suffering from allergic rhinoconjunctivitis and dyspnoea during summer may exhibit these symptoms after contact with flowers or dietary products of the elderberry tree Sambucus nigra.Objective Patients with a history of summer hayfever were tested in a routine setting for sensitization to elderberry. Nine patients having allergic symptoms due to elderberry and specific sensitization were investigated in detail. We studied the responsible allergens in extracts from elderberry pollen, flowers and berries, and investigated cross-reactivity with allergens from birch, grass and mugwort.Methods Sera from patients were tested for IgE reactivity to elderberry proteins by one-dimensional (1D) and 2D electrophoresis/immunoblotting. Inhibition studies with defined allergens and elderberry-specific antibodies were used to evaluate cross-reactivity. The main elderberry allergen was purified by gel filtration and reversed-phase HPLC, and subjected to mass spectrometry. The in-gel-digested allergen was analysed by the MS/MS sequence analysis and peptide mapping. The N-terminal sequence of the predominant allergen was analysed.Results 0.6% of 3668 randomly tested patients showed positive skin prick test and/or RAST to elderberry. IgE in patients' sera detected a predominant allergen of 33.2 kDa in extracts from elderberry pollen, flowers and berries, with an isoelectric point at pH 7.0. Pre-incubation of sera with extracts from birch, mugwort or grass pollen rendered insignificant or no inhibition of IgE binding to blotted elderberry proteins. Specific mouse antisera reacted exclusively with proteins from elderberry. N-terminal sequence analysis, as well as MS/MS spectrometry of the purified elderberry allergen, indicated homology with ribosomal inactivating proteins (RIPs).Conclusion We present evidence that the elderberry plant S. nigra harbours allergenic potency. Independent methodologies argue for a significant homology of the predominant 33.2 kDa elderberry allergen with homology to RIPs. We conclude that this protein is a candidate for a major elderberry allergen with designation Sam n 1.

Notes: Background:  Germins and the related germin-like proteins (GLPs) are glycoproteins expressed in many plants in response to biotic and abiotic stress. To test the potential impact of germins and GLPs, recombinant germin from Triticum aestivum (tGermin) and GLPs from Arabidopsis thaliana (tGLP), both produced in transformed tobacco plants, were used.Methods:  Sera from 82 patients with type I allergy to birch, grass or mugwort pollen and/or wheat were tested in immunoblot for IgE binding to tGermin and tGLP, and the IgE reactivity after chemical and enzymatic deglycosylation was analysed. The biological activity of tGermin and tGLP was determined in a histamine release assay and in skin prick testing (SPT).Results:  In an immunoblotting assay, 24 out of 82 tested sera (29.26%) from allergic patients showed IgE-binding to tGermin, and 18 of these sera (21.95%) displayed also IgE-binding to tGLP. The deglycosylation experiments indicated that glycan moieties contribute significantly to the IgE-binding of tGermin and tGLP. Both tGermins and tGLP induced specifically histamine release in an invitro assay as well as in SPT.Conclusion:  Our in vitro and in vivo findings demonstrate that germin and GLPs are capable to bind IgE most likely via carbohydrate determinants, and represent allergenic molecules.

Notes: Background  Thaumetopoea processionea L. (order Lepidoptera), the oak processionary moth, is found in oak forests in most European countries. Its third to sixth larval instars are armed with poisonous hairs (setae) containing an urticating toxin (thaumetopoein) potentially harmful to humans. Because T. processionea infests trees at the edges of forests or standing alone people frequently come into contact with its setae. In the woodland bordering on the western suburbs of Vienna conditions favouring its increase have led to frequent outbreaks of lepidopterism.Objectives  To determine the incidence of lepidopterism in a suburban environment with three separate caterpillar-infested oak trees and to ascertain the frequency of the various symptoms of lepidopterism and the manner of contact with setae.Methods  We conducted a telephone survey of all the households/institutions located within 500 m of the infested trees. To gain more information on patients' symptoms and on situations likely to lead to increased contact with setae we asked those who reported cutaneous reactions to complete a questionnaire. As part of the environmental study we described the outbreak site, examined patients and, with tape-strip samples taken from the surface of the soil, looked for setae persisting in the environment.Results  Of 1025 people surveyed 57 (5·6%) reported one or more symptoms of lepidopterism: 55 (96%) reported pruritus, 54 (95%) dermatitis, eight (14%) conjunctivitis, eight (14%) pharyngitis and two (4%) respiratory distress. The questionnaire was returned by 37 (69%) of the individuals with dermatitis. Of those, 16% had reacted with weal formation, 49% with papular rash and 22% with toxic irritant dermatitis. In 13% of respondents it was not possible to define the reaction. The risk factor analysis showed that airborne contamination was the most important cause: 97% of people had frequently passed an infested tree, 57% lived near a tree (in a neighbouring garden) and 32% had a tree in their own garden. Direct contact with larvae was of minor importance (38%). In four of the tape-strip samples intact setae were identified 1 year after the infestation.Conclusions  Lepidopterism caused by T. processionea is a public health problem of increasing significance. In years with outbreaks of the pest it can reach epidemic proportions in communities located near infested trees. Contact with airborne setae was mainly responsible for the occurrence of the disease.