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Background: IgE cross‐sensitization to major birch pollen allergen Bet v 1 and pathogenesis‐related (PR10) plant food allergens is responsible for the pollen‐food allergy syndrome. Methods: We designed a recombinant protein, AB‐PreS, consisting of non‐allergenic peptides derived from the IgE‐binding sites of Bet v 1 and the cross‐reactive apple allergen, Mal d 1, fused to the PreS domain of HBV surface protein as immunological carrier. AB‐PreS was expressed in E. coli and purified by chromatography. The allergenic and inflammatory activity of AB‐PreS was tested using basophils and PBMCs from birch pollen allergic patients. The ability of antibodies induced by immunization of rabbits with AB‐PreS and birch pollen extract‐based vaccines to inhibit allergic patients IgE binding to Bet v 1 and Mal d 1 was assessed by ELISA. Results: IgE‐binding experiments and basophil activation test revealed the hypoallergenic nature of AB‐PreS. AB‐PreS induced lower T‐cell activation and inflammatory cytokine production in cultured PBMCs from allergic patients. IgG antibodies induced by five injections with AB‐PreS inhibited allergic patients' IgE binding to Bet v 1 and Mal d 1 better than did IgG induced by up to 30 injections of six licensed birch pollen allergen extract‐based vaccines. Additionally, immunization with AB‐PreS induced HBV‐specific antibodies potentially protecting from infection with HBV. Conclusion: The recombinant AB‐PreS‐based vaccine is hypoallergenic and superior over currently registered allergen extract‐based vaccines regarding the induction of blocking antibodies to Bet v 1 and Mal d 1 in animals. [ABSTRACT FROM AUTHOR]

Background: Long‐time data of peanut allergy over time is sparse. We aimed to study the longitudinal development of sensitization to peanut extract and storage protein allergen molecules and associations with asthma status, airway and systemic inflammation markers. Methods: The Swedish birth cohort BAMSE followed 4089 participants with questionnaires, clinical investigations and blood sampling between 0 and 24 years. Information on (i) background factors at 2 months, (ii) peanut allergy symptoms and IgE data (ImmunoCAP) at 4, 8, 16, and 24 years, and (iii) IgE to storage proteins, lung function data including exhaled nitric oxide (FENO) as well as systemic inflammatory markers at 24 years of age were collected. Results: The prevalence of peanut extract sensitization, defined as IgE ≥ 0.35 kUA/L, was 5.4%, 8.0%, 7.5%, and 6.2% at 4, 8, 16, and 24 years of age, respectively. Between 8 and 24 years of age, (33/1565) participants developed IgE‐ab to peanut extract (median 1,4, range 0.7–2.6 kUA/L), and among those 85% were also sensitized to birch. Only six individuals developed sensitization to Ara h 2 (≥0.1 kUA/L) between 8 and 24 years of age, of whom three had an IgE‐ab level between 0.1–0.12 kUA/L. Storage protein sensitization was associated with elevated FENO, blood eosinophils and type 2 inflammation‐related systemic proteins. Conclusion: Sensitization to peanut extract after 4 years of age is mainly induced by birch cross‐sensitization and IgE to Ara h 2 rarely emerges after eight years of age. Storage protein sensitization is associated with respiratory and systemic inflammation. [ABSTRACT FROM AUTHOR]

Background: Factors predicting allergic sensitization in the first 6 months of life are poorly understood. We aimed to determine whether eczema, dry skin, and high transepidermal water loss (TEWL) at 3 months were associated with allergic sensitization at 6 months of age and, secondarily, to establish whether these characteristics predicted sensitization from 3 to 6 months of age. Methods: At 3 months of age, 1,994 infants from the population‐based PreventADALL birth cohort in Norway and Sweden were assessed for eczema and dry skin on the cheeks and/or extensors; impaired skin barrier function, defined as TEWL in the upper quartile (>9.4 g/m2/h), and allergen‐specific IgE levels <0.1 kUA/L, available in 830. At 6 months, we assessed allergic sensitization to any food (egg, cow's milk, peanut, wheat, soy) or inhalant (birch, timothy grass, dog, and cat) allergen by a skin prick test wheal diameter ≥2 mm larger than negative control. Results: Any sensitization was found in 198 of the 1,994 infants (9.9%), the majority to food allergens (n = 177, 8.9%). Eczema, dry skin, and high TEWL at 3 months increased the risk of sensitization at 6 months; adjusted odds ratios 4.20 (95% CI 2.93–6.04), 2.09 (95% CI 1.51–2.90) and 3.67 (95% CI 2.58–5.22), respectively. Eczema predicted sensitization with 55.6% sensitivity and 68.1% specificity; dry skin with 65.3% sensitivity and 57.3% specificity; and high TEWL with 61.7% sensitivity and 78.1% specificity. Conclusion: Eczema, dry skin, and high TEWL at 3 months predicted allergic sensitization at 6 months of age. [ABSTRACT FROM AUTHOR]

To the editor, Diagnosis of dog allergy in children relies mainly on clinical history and the presence of IgE antibodies (IgE) against dog dander. There were too few positive BAT responses for the minor allergens Can f 3 (n = 5), Can f 4 (n = 8), and Can f 6 (n = 5) to allow further analysis. Int Arch Allergy Immunol. 2013; 161 (1): 87 - 90. 4 Dahlen B, Nopp A, Johansson SG, Eduards M, Skedinger M, Adedoyin J. Basophil allergen threshold sensitivity, CD-sens, is a measure of allergen sensitivity in asthma. [Extracted from the article]

Current data indicate that the "bronchiolitis" diagnosis comprises more than one condition. Clinically, pathophysiologically, and even genetically three main clusters of patients can be identified among children suffering from severe bronchiolitis (or first wheezing episode): (a) respiratory syncytial virus (RSV)‐induced bronchiolitis, characterized by young age of the patient, mechanical obstruction of the airways due to mucus and cell debris, and increased risk of recurrent wheezing. For this illness, an effective prophylactic RSV‐specific monoclonal antibody is available; (b) rhinovirus‐induced wheezing, associated with atopic predisposition of the patient and high risk of subsequent asthma development, which may, however, be reversed with systemic corticosteroids in those with severe illness; and (c) wheeze due to other viruses, characteristically likely to be less frequent and severe. Clinically, it is important to distinguish between these partially overlapping patient groups as they are likely to respond to different treatments. It appears that the first episode of severe bronchiolitis in under 2‐year‐old children is a critical event and an important opportunity for designing secondary prevention strategies for asthma. As data have shown bronchiolitis cannot simply be diagnosed using a certain cutoff age, but instead, as we suggest, using the viral etiology as the differentiating factor. Respiratory syncytial virus‐induced bronchiolitis and rhinovirus‐induced first wheezing episode are the main clusters of severe bronchiolitis in less than 2‐year‐old children. It is important to distinguish these overlapping patient groups since they differ clinically, pathophysiologically, and genetically and are likely to respond to different treatments. The first episode of severe bronchiolitis appears to be a critical event and an opportunity for designing secondary prevention strategies for asthma. [ABSTRACT FROM AUTHOR]

First, regarding the definitions of bronchiolitis and wheeze, Manti et al state that bronchiolitis and wheezing are profoundly different clinical entities without overlap and therefore require different diagnostic and therapeutic approaches. 4 Lehtinen P, Ruohola A, Vanto T, Vuorinen T, Ruuskanen O, Jartti T. Prednisolone reduces recurrent wheezing after a first wheezing episode associated with rhinovirus infection or eczema. [Extracted from the article]