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Aim: Molecular sensitization profile analyses of allergic individuals to the house dust mites (HDM) Blomia tropicalis and Dermatophagoides pteronyssinus from Brazil and Austria, in the attempt to comprehend the individual contribution of the molecular components in the diagnosis of HDM allergy. Methodology: These analyses were made using a new in vitro multiplex allergen assay which allows simultaneous measurement of specific IgE against the whole allergen extract as well its components. Results and Conclusion: The data showed that in Brazil the inclusion of the molecular components Blo t 5 and/or Blo t 21 major allergens and Blo t 2 can increase the sensitivity and specificity of the assay for the diagnosis of allergy to B. tropicalis, using matrix‐based methodologies. Also we highlighted, for the first time, the importance of Blo t 2 analysis for a sensitive diagnosis, since some individuals were sensitized only to this molecular component. Regarding the sensitization profile of individuals sensitized to D. pteronyssinus, we point out the importance of analyzing the molecular components Der p23 and Der p 7, in addition to Der p 1 and Der p 2 for an accurate diagnosis based on matrices. [ABSTRACT FROM AUTHOR]

Pollinosis is sub-diagnosed and rarely studied in tropical countries. Cashew tree pollen has been reported as an allergen source although the knowledge of its immunoglobulin E (IgE)-reactive molecules is lacking. Therefore, this work aimed to identify IgE-reactive molecules and provide a proteomic profile of this pollen. From the 830 proteins identified by shotgun analysis, 163 were annotated to gene ontology, and a list of 39 proteins filtered for high confidence was submitted to the Allfam database where nine were assigned to allergenic families. Thus, 12 patients from the northeast of Brazil with persistent allergic rhinitis and aggravation of symptoms during cashew flowering season were selected. Using a 2D-based approach, we identified 20 IgE-reactive proteins, four already recognized as allergens, including a homolog of the birch isoflavone-reductase (Bet v 6). IgE-reactivity against the extract in native form was confirmed for five patients in ELISA, with three being positive for Bet v 6. Herein, we present a group of patients with rhinitis exposed to cashew tree pollen with the first description of IgE-binding proteins and a proteomic profile of the whole pollen. Cashew tree pollen is considered an important trigger of rhinitis symptoms in clinical practice in the northeast of Brazil, and the elucidation of its allergenic molecules can improve the diagnostics and treatment for allergic patients.

Scope: Manioc (Manihot esculenta) is a tuber mainly consumed in the Southern Hemisphere and used worldwide by food and chemistry industry. We aimed to recombinantly produce and characterize the first manioc allergen and evaluate its IgE reactivity in sera of Brazilian and Italian patients., Methods and Results: The molecule, termed Man e5, was expressed in E. coli, characterized by amino acid analysis, mass spectrometry, circular dichroism, HPLC, and dynamic light scattering. A tertiary structural model of the protein was produced using bioinformatics and susceptibility to pepsin digestion was analyzed in vitro. Based on its high content of charged residues, heat stability, flexibility and lack of secondary structure elements, the allergen was determined a member of the intrinsically disordered protein family. Brazilian patients were selected based on manioc allergy and Italians based on latex allergy and sensitization to Hev b 5.71% of Brazilians and 40% of Italians were in vitro IgE positive to Man e5. Cross-inhibition assays suggest a possible involvement of this allergen in the latex-fruit syndrome., Conclusion: Man e5, the first purified allergen from manioc demonstrates IgE cross-reactivity with Hev b 5. Data suggest Hev b 5 might act as primary sensitizer and could therefore lead to allergic manifestations upon manioc consumption without prior exposition., (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)