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The article discusses use of allergen‐specific immunotherapy (AIT) to cure allergic diseases by attacking their antigen‐specific immunologic mechanisms. Topics include better standardization of allergen products for diagnosis and therapy with molecular allergology, selection of molecules in order to identify genuine sensitization to the allergen, and producing recombinant molecules with hybrid technology.

The article reports on studies linking helminthic infections and allergic asthma. The link has been long established, but a series of recent studies show that helminthic infection has a much broader range of effects than previously thought. Early infection was seen as a prevention against later allergic reactions, with deworming contributing to onset of asthma later in childhood. A study published in this issue of the journal demonstrates that reducing helminthiases did not increase allergic symptoms, exercise-induced asthma or atopic sensitisation.

Objectives: Detection of allergen-specific immunoglobulin E (sIgE) is important for the diagnosis of allergy. IgE sensitization is commonly demonstrated in vivo by skin prick testing (SPT), or in vitro utilizing automated systems. Recently, HYCOR® Biomedical launched its new system for allergen sIgE testing called the NOVEOS™ Immunoanalyzer. This study aims to evaluate the analytical performance of the NOVEOS system in a bi-center study at Philipps-University Marburg (Site-1) and Charité Medical University Berlin (Site-2), respectively. Methods: The analytical performance was evaluated based on the guidelines I/LA20-A3, EP5-A3, EP17-A2, EP6-A, EP7-A3, and EP9-A3 of the Clinical and Laboratory Standards Institute (CLSI). Results: The conducted repeatability and within-laboratory precision tests provided acceptable performance with 3.0%–11.9% coefficient of variation across both sites. The limit of blank (LoB) and limit of detection (LoD) were <0.1 kU/L at both centers. A within-parameter linearity for all tested allergens was reported at both sites. Of note, no significant interference was observed for high levels of biotin, methylprednisolone, diphenhydramine, omalizumab, or ranitidine. Method comparison between the NOVEOS calibration and the latest World Health Organization (WHO) reference standard showed good agreement at both sites. Conclusions: The results from the analytical performance of the NOVEOS allergen sIgE assay and instrument testing at both sites were comparable. Overall, a good precision and linearity as well as a detection limit <0.1 kU/L were observed, with minimal impact of common interfering substances on patient recoveries. The NOVEOS is calibrated to the latest WHO reference standard and adds benefits like a small sample size and para-magnetic microparticles that improve upon third-generation allergen sIgE assays' design and performance. [ABSTRACT FROM AUTHOR]

Background Previous studies of serum total IgE (t-IgE) were not able to discriminate well-enough atopic from non-atopic subjects, that is, with or without serum-specific IgE antibodies to allergens. Objectives To model growth curves of the total IgE levels in children without atopic sensitization (hereafter defined as 'normal' t-IgE levels) and to test their usefulness in predicting atopic sensitization. Methods The German Multicentre Allergy Study ( MAS), a birth cohort with 1314 recruited newborns, began in 1990 and examined the participants until age 20 years. Total and specific IgE (t-IgE, s-IgE) were analyzed with a fluorescent enzyme immunoassay Immuno CAP ( TFS, Sweden) at ages 1, 2, 3, 5, 6, 7, 10, 13, and 20 years. Participants were classified as 'never atopic' if all their available serum samples had negative response (cutoff: <0.35 kUA/L) for s-IgE to the nine common foodborne and airborne allergenic extracts (milk, egg, soy, wheat, house dust mite, cat, dog, birch, and grass) tested in the MAS birth cohort. By contrast, participants were defined as atopic if they had, for at least at one available serum sample, s-IgE≥0.35 kUA/L to at least one allergenic extract tested. The evolution of t-IgE levels in the 'never atopic' children was described by growth curves, estimated by exploiting a quantile regression model. A 'reference' percentile, based on the t-IgE value measured at age 5 years, was assigned to each child with no IgE sensitization at that age. Upward deviations from the own 'reference' quantile of t-IgE in atopic and 'never atopic' children were calculated and a ROC analysis was used to identify the best cutoff point for predicting atopic sensitization. Results Overall, 1113 of 1314 children were included in this analysis. Of these, 469 were 'never atopic' and 644 atopic. Quantile trajectories of t-IgE levels in 'never atopic' subjects were stable from 5 years of age, increased to a plateau at age 10-13 years, and decreased slightly afterward. The onset of atopic s-IgE responses was characterized by an upward deviation of serum t-IgE levels from their 'reference' trajectory. T-IgE quantiles predicted the onset of atopy with high efficiency ( AUC>80%). ROC analysis showed that deviations from the t-IgE level 'reference' quantile above 0.32, 0.41, 0.42, 0.30, and 0.58 kU/L (log-units) at 6, 7, 10, 13, and 20 years of age, respectively, predicted an atopic sensitization. Conclusion The growth curves of 'normal' serum t-IgE concentrations were estimated in 'never atopic' children; for each individual who was non-atopic at 5 years of age a 'reference' quantile was identified that represented the individual's 'normal' level of t-IgE production. Upward deviations of observed t-IgE levels from the own 'reference' quantile, from 6 to 20 years of age, predicted at each year the occurrence of atopic sensitization. Clinical Implications The trajectory of t-IgE levels can be elaborated since age 5 years in non-atopic children. A child whose t-IgE levels are consistently higher than those predicted by his/her growth curve may have developed atopic sensitization. [ABSTRACT FROM AUTHOR]

Background There is a need to establish the effectiveness, cost-effectiveness, and safety of allergen immunotherapy ( AIT) for the prevention of allergic disease. Methods Two reviewers independently screened nine international biomedical databases. Studies were quantitatively synthesized using random-effects meta-analyses. Results A total of 32 studies satisfied the inclusion criteria. Overall, meta-analysis found no conclusive evidence that AIT reduced the risk of developing a first allergic disease over the short term ( RR = 0.30; 95% CI: 0.04-2.09) and no randomized controlled evidence was found in relation to its longer-term effects for this outcome. There was, however, a reduction in the short-term risk of those with allergic rhinitis developing asthma ( RR = 0.40; 95% CI: 0.30-0.54), with this finding being robust to a pre-specified sensitivity analysis. We found inconclusive evidence that this benefit was maintained over the longer term: RR = 0.62; 95% CI: 0.31-1.23. There was evidence that the risk of new sensitization was reduced over the short term, but this was not confirmed in the sensitivity analysis: RR = 0.72; 95% CI: 0.24-2.18. There was no clear evidence of any longer-term reduction in the risk of sensitization: RR = 0.47; 95% CI: 0.08-2.77. AIT appeared to have an acceptable side effect profile. Conclusions AIT did not result in a statistically significant reduction in the risk of developing a first allergic disease. There was, however, evidence of a reduced short-term risk of developing asthma in those with allergic rhinitis, but it is unclear whether this benefit was maintained over the longer term. We are unable to comment on the cost-effectiveness of AIT. [ABSTRACT FROM AUTHOR]