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Oral allergy syndrome (OAS) is one of the most common IgE-mediated allergic reactions. It is characterized by a number of symptoms induced by the exposure of the oral and pharyngeal mucosa to allergenic proteins belonging to class 1 or to class 2 food allergens. OAS occurring when patients sensitized to pollens are exposed to some fresh plant foods has been called pollen food allergy syndrome (PFAS). In the wake of PFAS, several different associations of allergenic sources have been progressively proposed and called syndromes. Molecular allergology has shown that these associations are based on IgE co-recognition taking place between homologous allergens present in different allergenic sources. In addition, the molecular approach reveals that some allergens involved in OAS are also responsible for systemic reactions, as in the case of some food Bet v 1-related proteins, lipid transfer proteins and gibberellin regulated proteins. Therefore, in the presence of a convincing history of OAS, it becomes crucial to perform a patient’s tailored molecule-based diagnosis in order to identify the individual IgE sensitization profile. This information allows the prediction of possible cross-reactions with homologous molecules contained in other sources. In addition, it allows the assessment of the risk of developing more severe symptoms on the basis of the features of the allergenic proteins to which the patient is sensitized. In this context, we aimed to provide an overview of the features of relevant plant allergenic molecules and their involvement in the clinical onset of OAS. The value of a personalized molecule-based approach to OAS diagnosis is also analyzed and discussed.

Cupressaceae pollen causes allergic reactions worldwide with long-lasting symptomatic periods. Currently, no cypress polcalcin is available for diagnostic purposes. With the aim to investigate the pattern of sensitization to a cypress polcalcin, a synthetic gene of Jun o 4, the Juniperus oxycedrus 4EF-hand polcalcin, was cloned and expressed in Escherichia coli. Its features were investigated in comparison with the grass 2EF-hand Phl p 7. Rhinitis was the symptom most frequently reported in a cohort of Italian patients sensitized to rJun o 4 and/or rPhl p 7. The detection of many pollen allergic patients sensitized to the cypress polcalcin, but negative to Phl p 7, indicates that Phl p 7 cannot be further considered a marker of sensitization towards all the polcalcins. A 4EF-hand cypress polcalcin claims the inclusion in allergy diagnostic tests. In addition, the sensitivity of polcalcins to gastrointestinal digestion is reported and discussed for the first time.

Background Non-specific lipid transfer proteins (LTPs) are important allergens in fruits, pollen, vegetables, nuts and latex. Due to their compact structure, LTPs are highly resistant to heat treatment. Here, Art v 3 from mugwort pollen and Pru p 3 from peach were used as model allergens to in-depth investigate structural and immunological properties upon thermal treatment at different buffer conditions. Methods Recombinant Art v 3 and Pru p 3 were purified from E. coli and incubated at 95 °C up to 120 min using sodium phosphate buffer pH 3.4 or 7.3. Physicochemical properties of allergens were analyzed in circular dichroism spectroscopy, Fourier transform infrared spectroscopy, dynamic light scattering, size exclusion chromatography, and mass spectrometry. The crystal structure of Art v 3.0201 was determined to 1.9 A resolution. IgG and IgE binding was investigated in ELISA using murine and LTP allergic patients’ sera. Results Highly pure and homogenous recombinant allergens were obtained from bacterial production. The crystal structure of Art v 3.0201 revealed an antiparallel four helix bundle with a C-terminal extension mediating an asymmetric, transient dimer interface and differently sized cavities. Both allergens showed high thermal stability at acidic conditions. In contrast, extensive heat treatment in neutral buffer induced irreversible structural changes due to lanthionine-based cysteine rearrangement. This fostered loss of the typical α-helical structure, increased molecular size and abrogation of IgG and IgE binding epitopes. Pru p 3 lost its structural integrity at shorter heat stress duration than Art v 3, which did however only partially affect the molecule’s IgE binding epitopes. Conclusion During thermal treatment, susceptibility to structural changes of the LTP-fold is highly dependent on the surrounding environment but also on intrinsic features of individual LTPs. This is a crucial fact to consider when processing LTP-containing food or food products as this will directly influence their allergenic potential.

Peach and apricot can cause allergic reactions with symptoms ranging from mild to very severe, including anaphylaxis. Sometimes subjects allergic to fruits of the Prunus genus have been reported to be also allergic to rubber latex products. The objective of this study is the characterization of a newly identified peach and apricot protein showing similarities with the allergens Hey b 5 from rubber latex and Man e 5 from manioc. This protein has been named ENEA on the basis of the single letter amino acid code of the first four N-terminal residues of the isolated molecule. It has been found in very variable amounts in different peach cultivars and batches. ENEA was isolated from peach pulp extracts by chromatographic separations and identified by direct protein sequencing. At that time, the full length sequence was available only for the homologous protein of the taxonomically closely related apricot, which was produced as a recombinant molecule in Escherichia coli. The following availability of the full length sequence of peach ENEA revealed a very high identity (97%) with the apricot homolog. Similarly to Hey b 5 and to Man e 5, the structural characterization indicated that ENEA is an intrinsically disordered protein. The immunological properties, investigated by dot blotting, the ABA system and the FABER test, showed that ENEA is recognized by specific IgE of allergic patients. In a selected population of 31 patients reporting allergic reactions to peach fruit and/or IgE positive to Hey b 5, 28 and 27 subjects resulted co-sensitized to rENEA and Hey b 5 in the ABA and ISAC test, respectively. In a random population of 3305 suspected allergic patients, analyzed with the FABER test, 17 of them were sensitized to rENEA and 10 of them were also positive to Hey b 5. In addition, both the natural molecule from peach and the recombinant protein of apricot partially inhibited the IgE binding to Hey b 5. In conclusion, a new peach and apricot IgE-binding protein, cross-reacting with the major latex allergen Hey b 5, has been identified. Its variable concentration in the fruit might explain some occasionally occurring allergic reactions. The apricot molecule has recently been registered by the WHO/ IUIS Allergen Nomenclature Sub-Committee with the allergen name Pru ar 5. The recombinant form of apricot ENEA, now available, will contribute to allergy diagnosis.

The presence in cypress pollen of an important allergen, belonging to the gibberellin-regulated protein (GRP) family, has been suggested for many years. However, it has never been isolated and sometimes the homologous peach allergen, Pru p 7, has been used as a surrogate to perform immunological investigations. The aim of this study has been the isolation and molecular characterization of the GRP contained in the Cupressus sempervirens pollen. This protein, named Cypmaclein, has been purified from the natural source using conventional biochemical methods consisting in different chromatographic separations. Cypmaclein has been identified by direct protein sequencing of the N-terminal region and of internal fragments of the molecule. In SDS-PAGE, its apparent molecular mass is slightly higher than that of Pru p 7. Nevertheless, the mass spectrometry experiments reveal that the exact molecular mass of Cypmaclein (6821.88 Da) is very close to that of Pru p 7 (6909.90 Da). Two regions of Cypmaclein have been sequenced providing 50% of its primary structure. A high overall sequence identity of Cypmaclein with all the analyzed GRP has been observed, although in the N-terminal region the high identity is limited to the homolog of Cryptomeria japonica. In circular dichroism experiments Cypmaclein produced a spectrum overlapping that of Pru p 7. However, the comparative analysis of Cypmaclein, Pru p 7 and Pun g 7 IgE reactivity revealed a behavior that was not completely overlapping, thus suggesting that the IgE epitopes are only partially shared. In single point highest inhibition achievable assays performed with the FABER test, Cypmaclein efficiently competed with the allergenic peach and pomegranate GRP in the binding of specific IgE of patients sensitized to Pru p 7. In conclusion, the natural cypress pollen GRP has been isolated for the first time, its structural features have been investigated and its cross-reactivity with Pru p 7 and Pun g 7 has been demonstrated. This protein is now available for further investigations aimed at understanding its clinical relevance in the allergy to cypress pollen. In addition, the prevalence of sensitization directly to Cypmaclein, and not limited to the homologs, can be defined.

Allergic reactions caused by 9kDa Lipid Transfer Proteins (9k-LTP), such as Pru p 3, have been widely investigated, whereas a possible contribution of components of 7kDa LTP (7k-LTP) sub-family in triggering allergic symptoms has been overlooked so far. With the aim to investigate the contribution of 7k-LTPs to the food allergies, we have identified, isolated and characterised a tomato seed 7k-LTP (Sola l 7k-LTP). The protein was purified by chromatographic separations, identified by direct protein sequencing and mass spectrometry and a molecular model was built. Functional evaluation of the allergen has been performed by skin testing. Sola l 7k-LTP consists of 68 amino acids producing a molecular mass of 7045Da and displays 41% sequence identity with Pru p 3, the allergenic 9k-LTP from peach. IgE antibodies specifically recognising Sola l 7k-LTP were found within the population claiming tomato ingestion-related symptoms, but also in subjects tolerant on tomato exposure. A few subjects were mono-sensitised to Sola l 7k-LTP, which is biologically active as shown by the positive skin test. In line with the immunological results, the molecular model shows structural similarities between the IgE binding regions of the two sub-families. Therefore, Sola l 7k-LTP shares some structural and immunological features with Pru p 3, but it also displays individual features that could be responsible for mono-specific IgE binding. In conclusion, Sola l 7k-LTP is a new identified allergenic LTP, the description of which may contribute to the improvement of allergy diagnosis and to the formulation of a safe and personalised diet. In addition, to avoid current confusing classifications, a new nomenclature policy for LTP sub-families is proposed in this paper. We now suggest that 7-kDa LTP (so far named LTP2) be renamed 7k-LTP and 9-kDa LTP (so far named LTP1) be renamed 9k-LTP.

Allergy to pomegranate is often associated with severe symptoms. Two allergens have previously been described: 9k-LTP Pun g 1 and pommaclein Pun g 7. This study describes the isolation of a chitinase III, identified by direct protein sequencing and mass spectrometry. It is a 29-kDa protein showing 69% sequence identity with the latex hevamine and IgE binding in dot blotting, immunoblotting and FABER(center dot) test. Chitinase-specific IgE were detected in 69 of 357 patients sensitized to one or more pomegranate allergenic preparations present on the FABER(center dot) test. Using this test, 19.2% of the patients sensitized to kiwifruit chitinase IV were also sensitized to pomegranate chitinase III, rather than to latex chitinase I (7.2%) with which it shares the N-terminal hevein-like domain. In conclusion, a new allergen has been identified, contributing to improving food allergy diagnosis. This study reveals the important role of chitinases III and IV as allergy sensitizers and prompts further investigations.

Knowledge of the structural properties of allergenic proteins is a necessary prerequisite to better understand the molecular bases of their action, and also to design targeted structural/functional modifications. Peamaclein is a recently identified 7 kDa peach allergen that has been associated with severe allergic reactions in sensitive subjects. This protein represents the first component of a new allergen family, which has no 3D structure available yet. Here, we report the first experimental data on the 3D-structure of Peamaclein. Almost 75% of the backbone resonances, including two helical stretches in the N-terminal region, and four out of six cysteine pairs have been assigned by 2D-NMR using a natural protein sample. Simulated gastrointestinal digestion experiments have highlighted that Peamaclein is even more resistant to digestion than the peach major allergen Pru p 3. Only the heat-denatured protein becomes sensitive to intestinal proteases. Similar to Pru p 3, Peamaclein keeps its native 3D-structure up to 90°C, but it becomes unfolded at temperatures of 100-120°C. Heat denaturation affects the immunological properties of both peach allergens, which lose at least partially their IgE-binding epitopes. In conclusion, the data collected in this study provide a first set of information on the molecular properties of Peamaclein. Future studies could lead to the possible use of the denatured form of this protein as a vaccine, and of the inclusion of cooked peach in the diet of subjects allergic to Peamaclein.

Kiwifruit is an important cause of allergy. Although several allergens have been identified in this food ( www.allergome.org ), data on the number and clinical relevance of kiwifruit allergenic proteins are still fragmentary. With the aim of providing a contribution to the description of the complete kiwifruit allergome, we have investigated the immunological features of pectin methylesterase (PME) and its inhibitor (PMEI) purified from the natural source. Specific IgE to PME (Act d 7) and PMEI (Act d 6) were recorded in patients with kiwifruit allergies by immunoblotting, multiplex microarray-based immunoassay and skin testing (ST). Compared to the results obtained by the microarray system, the percentage of subjects detected positive to Act d 6 was much higher in the immunoblotting. Conversely, a similar percentage of subjects positive to Act d 7 was estimated in both the in vitro tests. Few subjects compared to in vitro testing gave a positive response on ST. In the case of Act d 7 this could be ascribed to the glycan side chain recognized by cross-reactive carbohydrate determinants (CCD)-specific IgE. In fact, Act d 7 fell in the cluster of glycoallergens (including Api m 1, Cup a 1, Hor v 17, Ole e 1, Pla a 2) immobilized on the microarray and recognized by CCD-specific IgE. A comparative analysis of different kiwifruit allergens (Act d 1, 2, 5, 6, 7, 11) revealed that only Act d 7 fell in this cluster, whereas Act d 2, although reported to be glycosylated, fell outside, thus suggesting the lack of sugars bound to this molecule. The subsequent biochemical characterization confirmed that Act d 2 is not a glycoallergen. In conclusion, Act d 7 and 6 seem to be rarely involved in causing symptoms in kiwifruit allergic patients. Nevertheless they are useful to understand a single patient profile and the mechanism of protein allergenicity. In addition, in this study the use of a multiplex test system has provided more information than expected, thus contributing to both the immunological and biochemical characterization of the immobilized allergens.

The consumption of pomegranate is increasing as it is considered a health-promoting food. Nevertheless, it can trigger allergic reactions, sometimes severe. The LTP Pun g 1 is the only pomegranate allergen so far reported. Based on preliminary clinical observations, the main aim of this study was the investigation of still unknown allergens contained in this fruit. Pommaclein, a homologue of peamaclein, the peach allergen Pru p 7, was isolated, identified by protein sequencing, and characterized as an IgE-binding protein by different test systems. RP-HPLC protein profiles revealed significant variations of LTP and pommaclein content in the red pulp of selected cultivars and accessions. Conversely, the mesocarp appeared free of proteins and much richer in antioxidants. In conclusion, a new allergen has been identified, and it could contribute to improving allergy diagnosis. The study highlights that pomegranate mesocarp could represent a rich and safe source of nutraceuticals also for allergic subjects.

Diagnostic tests to detect allergic sensitization were introduced at the end of the nineteenth century but only in the late 1990s did the advent of molecular allergology revolutionize the approach to the allergic patient. Personalized Medicine, a medical procedure that separates patients into different groups with different medical decisions, practices and interventions has sanctioned this change. In fact, in the last few years molecular allergology and the observation that not every patient has the same allergic profile, even when allergic to the same allergenic source, has originated the concept “one size does not fit all”. This new approach requires the identification of still unknown allergens, but also the more detailed investigation of those already known. In depth studies of the structure–function relationships in allergenic molecules can reveal the structural determinants involved in the IgE-binding. Then, the knowledge of the epitope profile of each allergen and of the environmental/experimental conditions affecting the exposure of IgE-binding epitopes can provide important contributions to the understanding of cross-reaction processes and to the improvement of diagnosis, immunotherapy and the overall patient treatment. The evolution of diagnostic systems cannot ignore these new needs in this field.

Few apple cultivars are widespread in the markets worldwide. The characterisation of cultivars available only in local markets could reveal fruits with sufficiently low amounts of allergens to be tolerated by at least some allergic subjects. This study was focused on the characterisation of 10 ancient and 2 widespread apple cultivars cultivated in Southern Italy. Pomological characterisation showed good sensory features and high manipulation resistance for most of the selected ancient cultivars. Individual patterns of allergenic components were obtained when IgE, IgG and IgG4 inhibition tests were performed on a multiplexed allergen microarray, using sera from allergic subjects as probes. Results obtained allow the selection of potentially hypo- or hyper-allergenic apple cultivars. In addition, this study describes a possible use of allergen microarray technology to quickly investigate the potential allergenicity of specific foods that, after additional tests, can be considered for the inclusion in the diet of individual allergic subjects.

Background: Diagnosis and immunotherapy of house-dust mite (HDM) allergy is still based on natural allergen extracts. The aim of this study was to analyze commercially available Dermatophagoides pteronyssinus extracts from different manufacturers regarding allergen composition and content and whether variations may affect their allergenic activity. Methods: Antibodies specific for several D. pteronyssinus allergens (Der p 1, 2, 5, 7, 10 and 21) were used to analyze extracts from 10 different manufacturers by immunoblotting. Sandwich ELISAs were used to quantify Der p 1 and Der p 2 in the extracts. Mite-allergic patients (n = 45) were skin-tested with the extracts and tested for immunoglobulin E (IgE) reactivity to a panel of 10 mite allergens (Der p 1, 2, 4, 5, 7, 8, 10, 14, 20 and 21) by dot blot. Results: Only Der p 1 and Der p 2 were detected in all extracts but their concentrations and ratios showed high variability (Der p 1: 6.0–40.8 µg ml–1; Der p 2: 1.7–45.0 µg ml–1). At least 1 out of 4 allergens (i.e. Der p 5, 7, 10 and 21) was not detected in 8 of the studied extracts. Mite-allergic subjects showed different IgE reactivity profiles to the individual mite allergens, the extracts showed different allergenic activity in skin-prick tests and false-negative results. Conclusions: Commercially available D. pteronyssinus extracts lack important allergens, show great variability regarding allergen composition and content and some gave false-negative diagnostic test results in certain patients.

Purpose of review To define the role of IgE-microarray testing in atopic dermatitis where the multifunctional environmental factors implicated in the pathogenesis of the disease deserve a complex and exhaustive approach for the finest definition of relevant allergenic triggers, if any. Recent findings Allergenic factors involved in atopic dermatitis have been reported in inducing atopic dermatitis. Environmental triggers, such as aeroallergens, food allergens, bacterial, and fungal antigen, and the presence of IgE to self-antigens have been described as well. The usefulness of the microarray testing has been preliminary described. Summary As far as the number of potential triggers or worsening factors in atopic dermatitis is quite broad, we foresee a crucial role for the IgE microarray testing. The microarray testing is helpful in defining all additional reactivity the atopic dermatitis patient could have acquired in her/his allergic life, mostly related to inhalant allergens. Nevertheless, interpretation needs skills and thus this new technology should rather be reserved for the allergologist as it may lead to false conclusions if broadly used in general medicine. IgE microarray testing gives trustable results to define the nonallergic atopic dermatitis form because of the broad and comprehensive negative IgE testing.

To cite this article: D’Avino R, Bernardi ML, Wallner M, Palazzo P, Camardella L, Tuppo L, Alessandri C, Breiteneder H, Ferreira F, Ciardiello MA, Mari A. Kiwifruit Act d 11 is the first member of the ripening-related protein family identified as an allergen. Allergy 2011; 66: 870–877. Abstract Background: Kiwifruit is an important cause of food allergy. A high amount of a protein with a molecular mass compatible with that of Bet v 1 was observed in the kiwifruit extract. Objective: To identify and characterize kirola, the 17-kDa protein of green kiwifruit (Act d 11). Methods: Act d 11 was purified from green kiwifruit. Its primary structure was obtained by direct protein sequencing. The IgE binding was investigated by skin testing, immunoblotting, inhibition tests, and detection by the ISAC microarray in an Italian cohort and in selected Bet v 1-sensitized Austrian patients. A clinical evaluation of kiwi allergy was carried out. Results: Act d 11 was identified as a member of the major latex protein/ripening-related protein (MLP/RRP) family. IgE binding to Act d 11 was shown by all the applied testing. Patients tested positive for Act d 11 and reporting symptoms on kiwifruit exposure were found within the Bet v 1-positive subset rather than within the population selected for highly reliable history of allergic reactions to kiwifruit. Epidemiology of Act d 11 IgE reactivity was documented in the two cohorts. IgE co-recognition of Act d 11 within the Bet v 1-like molecules is documented using the microarray IgE inhibition assay. Conclusions: Act d 11 is the first member of the MLP/RRP protein family to be described as an allergen. It displays IgE co-recognition with allergens belonging to the PR-10 family, including Bet v 1.

IgE-mediated allergic diseases are among the most prevalent diseases worldwide. The use of extracts in the skin test and the additional use of IgE testing still represent the current basis for the diagnostic work-up. During the past 30 years, knowledge of the molecular structure of allergens has increased dramatically, and the characterization and production of allergenic molecules, as natural purified compounds or recombinant products, is allowing us to approach the allergy diagnostic work-up differently. Much of this is based on the adoption of microtechnology since the first release of a biochip for IgE detection. Its use has prompted the development of new concepts linked to the diagnosis of allergic diseases. This review describes the background of allergy diagnosis and the tools currently used for specific IgE detection. It gives insight into the most recent advancement in the field of biotechnology leading to allergenic molecule availability, microtechnology leading to the routine use of protein biochips for IgE detection, and how they should be combined with information technology.

Summary Background The availability of allergenic molecules and high-throughput microtechnologies allow the collection of a large number of IgE results at the same time in a single test. This can be carried out applying the test in the routine diagnostic work-up. Objective The aim of this study was to make a cross-sectional evaluation of the raw prevalence of IgE reactivity to allergenic molecules in serum samples from a cohort of Italian patients using an innovative tool. Methods The ISAC, a microarray system, has been used for specific IgE detection using 75 different allergenic molecules. Sera were collected from 23 077 unselected consecutive individuals complaining about any allergic disease. Results Sixteen thousand four hundred and eight of 23 077 patients had IgE to at least one of 75 allergenic molecules. The top-ranked molecules in this cohort were Cup a 1 (42.7%), Der f 2 (38.7%), and Phl p 1 (37.9%), whereas all the other allergens tested scored in a range between 36.8% and 0.04%, including the first food allergen, Pru p 3, ranked 15th (9.79%). Prevalence varied quite markedly depending on the age range considered, and showing a different behaviour in the lifetime sensitization process. Unsupervised two-way hierarchical clustering analysis generated distinctive patterns of reactivity as the result of IgE recognition of either homologous allergens belonging to different biological sources or non-homologous belonging to the same biological source. Conclusions Allergen-based microarray is a tool for the detection of IgE-related sensitization to panels of allergens and gives a more precise and comprehensive evaluation for an IgE-based epidemiology. This insight brings data for better understanding of the sensitization process.

Summary Background Oral food challenge (OFC) is the diagnostic ‘gold standard’ of food allergies but it is laborious and time consuming. Attempts to predict a positive OFC through specific IgE assays or conventional skin tests so far gave suboptimal results. Objective To test whether skin test with titration curves predict with enough confidence the outcome of an oral food challenge. Methods Children (n=47; mean age 6.2 ± 4.2 years) with suspected and diagnosed allergic reactions to hen's egg (HE) were examined through clinical history, physical examination, oral food challenge, conventional and end-point titrated skin tests with HE white extract and determination of serum specific IgE against HE white. Predictive decision points for a positive outcome of food challenges were calculated through receiver operating characteristic (ROC) analysis for HE white using IgE concentration, weal size and end-point titration (EPT). Results OFC was positive (Sampson's score 3) in 20/47 children (42.5%). The area under the ROC curve obtained with the EPT method was significantly bigger than the one obtained by measuring IgE-specific antibodies (0.99 vs. 0.83, P

Knowledge of the structural properties of allergenic proteins is a necessary prerequisite to better understand the molecular bases of their action, and also to design targeted structural/functional modifications. Peamaclein is a recently identified 7 kDa peach allergen that has been associated with severe allergic reactions in sensitive subjects. This protein represents the first component of a new allergen family, which has no 3D structure available yet. Here, we report the first experimental data on the 3D-structure of Peamaclein. Almost 75% of the backbone resonances, including two helical stretches in the N-terminal region, and four out of six cysteine pairs have been assigned by 2D-NMR using a natural protein sample. Simulated gastrointestinal digestion experiments have highlighted that Peamaclein is even more resistant to digestion than the peach major allergen Pru p 3. Only the heat-denatured protein becomes sensitive to intestinal proteases. Similar to Pru p 3, Peamaclein keeps its native 3D-structure up to 90°C, but it becomes unfolded at temperatures of 100-120°C. Heat denaturation affects the immunological properties of both peach allergens, which lose at least partially their IgE-binding epitopes. In conclusion, the data collected in this study provide a first set of information on the molecular properties of Peamaclein. Future studies could lead to the possible use of the denatured form of this protein as a vaccine, and of the inclusion of cooked peach in the diet of subjects allergic to Peamaclein. 2014 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 102: 416-425, 2014.

Background: FABER 244 is a new in vitro multiplex test for specific IgE detection using 122 molecular allergens and 122 allergenic extracts, coupled to chemically activated nanoparticles. Allergenic preparations, either produced in house or obtained from commercial providers, are individually coupled to nanobeads by means of optimized protocols to achieve maximum test performance. Aim: To measure the diagnostic accuracy of FABER 244-122-122 01 by comparing with the ImmunoCAP ISAC 112 (TFS, Sweden) in patients allergic to LTP proteins shared by both tests. Methods: A real life study as been set by analyzing the clinical records, and the FABER and ISAC test results from 94 consecutive patients referred to CAAM from March 2015 to August 2016. Data were extracted from the electronic medical record InterAll. The diagnostic accuracy measurement and test comparison were performed on 3 LTP proteins (Cor a 8, Jug r 3, Pru p 3) adopting the patients' symptoms as gold standard and MedCalc as software for statistical analysis. ISAC test Limit of Detection (LoD) was set to 0.3 ISU whereas FABER LoD was set to 0.01 FIU. In the overall analysis attention has been put on additional information coming from non-shared LTPs, Tri a 14 and Ara h 9 for ISAC, and Act d 10, Pun g 1, Sola l 6, Tri a 7k-LTP, Zea m 14 plus peanut and wheat extracts available on FABER. Results-Discussion: Both tests appear to be accurate and well aligned to each other for all three analyzed LTP proteins. In terms of sensitivity FABER performs better than ISAC on Cor a 8 (100% vs 73%), same as ISAC on Jug r 3 (100% both) and FABER better than ISAC on Pru p 3 (96% vs 91%). In terms of specificity FABER performs better than ISAC on Cor a 8 (96% vs 94%), same as ISAC on Jug r 3 (96%), whilst ISAC performs better on Pru p 3 (97% vs 92%). IgE detection by ISAC Ara h 9 and Tri a 14 was compensated by the peanut and wheat extracts, whereas info on additional food LTPs could be obtained from the FABER extended panel including 25 extracts from plant-derived foods bearing LTPs. Conclusions: FABER test is a new in vitro test for specific IgE detection, including molecules and extracts. Considering the food allergen group belonging to the LTP, FABER appears to be accurate and in good agreement with ISAC results. The specific advantage of FABER relies on the chance of testing patients to a broader panel of LTP as well as to a large number of extracts, complementing the results on single allergenic molecules.

Rotaviruses are one of the most important causes of gastroenteritis in children under 5 years old. Analysis of G and P rotavirus genotypes in circulation is crucial in evaluating the appropriacy of mass vaccination of children worldwide. Overall, 592 stool samples were collected in Tirana (Albania), the Salento peninsula (South Italy), and three different hospitals in Rome (Central Italy). Of the total samples, 31.3% were rotavirus positive in Albania, 78.3% in the Salento, and 40.3% in Rome. The samples collected in Tirana and Rome were G-P typed, whereas the samples collected in the Salento were only G typed. Overall, in Italy the most frequent combinations were G4 P[8] (54.5%), G1 P[8] (27.3%), and G2 P[4] (18.2%); in Albania they were G9 P[8] (72.1%), G4 P[8] (8.8%), G1 P[8] (5.9%), and G2 P[4] (2.9%). The prevalence in Albania of atypical combinations was 7.4% for G4 P[4] and 2.9% for G9 P[4]. Phylogenetic analysis was also performed to assess the genetic relatedness of the strains. J. Med. Virol. 82:510-518, 2010. (c) 2010 Wiley-Liss, Inc.

It is currently accepted that viral infections may influence the development of atopy. In the present study we evaluated serum IgE levels as well as the prevalence of symptoms indicative of atopic disease and EBV antibodies in 353 children aged from 1 month to 19 years. Antibodies against EBV were detected by immunofluorescence. IgE levels in serum were measured by enzyme immunoassay. Dividing the study population according to EBV seropositivity and age, we noted that the prevalence of high IgE levels (> 2 s.d.) was, in total, more frequent in the EBV negative (32.9%) than in the positive subjects (27.6%). Interestingly, this higher prevalence was found only in the groups aged under six, especially in the 7 to 29 month group, where it was statistically significant (p=0.037), whereas in the 6-19 year group the situation was reversed. Furthermore, selecting only the atopic children younger than 3 years of age with high IgE levels and clinical symptoms of atopy (wheezing and/or dermatitis) it was possible to demonstrate lower EBV seropositivity compared with the normal IgE controls for each group, even though these differences were not statistically significant. In conclusion, the results of our study suggest that, in our selected population, EBV infection in the first years of life is associated with a lower prevalence of high IgE levels.

Background From patients’ reports and our preliminary observations, a fully maturated cheese (Parmigiano-Reggiano; PR) seems to be well tolerated by a subset of cow’s milk (CM) allergic patients. Objective and Methods To biochemically and immunologically characterize PR samples at different maturation stage and to verify PR tolerability in CM allergic children. Seventy patients, with suspected CM allergy, were enrolled. IgE to CM, α-lactalbumin (ALA), β-lactoglobulin (BLG) and caseins (CAS) were tested using ImmunoCAP, ISAC103 and skin prick test. Patients underwent a double-blind, placebo-controlled food challenge with CM, and an open food challenge with 36 months-maturated PR. Extracts obtained from PR samples were biochemically analyzed in order to determine protein and peptide contents. Pepsin and trypsin-chymotrypsin-pepsin simulated digestions were applied to PR extracts. Each PR extract was investigated by IgE Single Point Highest Inhibition Achievable assay (SPHIAa). The efficiency analysis was carried out using CM and PR oral challenges as gold standards. Results The IgE binding to milk allergens was 100% inhibited by almost all PR preparations; the only difference was for CAS, mainly αS1-CAS. Sixteen patients sensitized to CM tolerated both CM and PR; 29 patients tolerated PR only; 21 patients, reacted to both CM and PR, whereas 4 patients reactive to CM refused to ingest PR. ROC analysis showed that the absence of IgE to BLG measured by ISAC could be a good marker of PR tolerance. The SPHIAa using digested PR preparations showed a marked effect on IgE binding to CAS and almost none on ALA and BLG. Conclusions 58% of patients clinically reactive to CM tolerated fully maturated PR. The preliminary digestion of CAS induced by PR maturation process, facilitating a further loss of allergenic reactivity during gut digestion, might explain the tolerance. This hypothesis seems to work when no IgE sensitization to ISAC BLG is detected.

Few apple cultivars are widespread in the markets worldwide. The characterisation of cultivars available only in local markets could reveal fruits with sufficiently low amounts of allergens to be tolerated by at least some allergic subjects. This study was focused on the characterisation of 10 ancient and 2 widespread apple cultivars cultivated in Southern Italy. Pomological characterisation showed good sensory features and high manipulation resistance for most of the selected ancient cultivars. Individual patterns of allergenic components were obtained when IgE, IgG and IgG4 inhibition tests were performed on a multiplexed allergen microarray, using sera from allergic subjects as probes. Results obtained allow the selection of potentially hypo- or hyper-allergenic apple cultivars. In addition, this study describes a possible use of allergen microarray technology to quickly investigate the potential allergenicity of specific foods that, after additional tests, can be considered for the inclusion in the diet of individual allergic subjects.

BACKGROUND: Hen's egg allergy ranks among the most frequent primary food allergies in children. We aimed to investigate sensitization profiles of egg allergic patients and compare in vitro IgE reactivities of eggs from ancient chicken breeds (Araucana and Maran) with those from conventional laying hen hybrids. METHODOLOGY: Egg allergic children (n = 25) were subjected to skin prick test, double blind placebo controlled food challenge, and sensitization profiles to Gal d 1-5 were determined by allergen microarray. IgE binding and biological activity of eggs from different chicken breeds were investigated by immunoblot, ELISA, and mediator release assays. PRINCIPAL FINDINGS: We found that Gal d 1 and Gal d 2 are generally major egg allergens, whereas Gal d 3-5 displayed high sensitization prevalence only in patients reacting to both, egg white and yolk. It seems that the onset of egg allergy is mediated by egg white allergens expanding to yolk sensitization in later stages of disease. Of note, egg white/yolk weight ratios were reduced in eggs from Auraucana and Maran chicken. As determined in IgE immunoblots and mass analysis, eggs from ancient chicken breeds did not differ in their protein composition. Similar IgE-binding was observed for all egg white preparations, while an elevated allergenicity was detected in egg yolk from Araucana chicken. CONCLUSION/SIGNIFICANCE: Our results on allergenicity and biological activity do not confirm the common assumption that aboriginal food might be less allergenic. Comprehensive diagnosis of egg allergy should distinguish between reactivity to hen's egg white and yolk fractions to avoid unnecessary dietary restrictions to improve life quality of the allergic child and its family.

Background Food allergy is becoming a major public health concern in recent times. Several sesame seed allergenic proteins have been identified. However, sensitization toward these proteins does not follow a common and unique pattern of clinical reactivity, as shown by the differential geographic recognition of single proteins. Objective To evaluate the sensitization profiles of 18 Italian individuals who experienced clinical symptoms after sesame seed consumption, including 4 anaphylactic reactions. Methods Using an in vitro approach, we adopted a 2-dimensional electrophoretic technique combined with immunoblotting analyses by using sera from 18 Italian sesame-allergic patients. Results We showed the prevalent and almost exclusive reactivity of the sesame 11S globulin. We shed light on the active role of the basic subunit of this globulin family. The limited accessibility of this polypeptide chain, unless the interchain disulphide bonds are cleaved, may be one of the reasons for its structural/functional stability and, thus, great potential for induction of IgE reactivity. Conclusions These results confirmed previous findings on the reactivity of the basic subunit of 11S globulin in various legume species. Moreover, this experimental approach proved to be useful for the noninvasive screening of specific reactivities in sensitized patients.

Hypersensitivity to hen egg (HE) is a common cause of food allergy in children. Clinical and serological crossreactivity between hen egg proteins and those of other birds eggs (turkey, duck, goose, sea-gull) have been described (1). Only serological cross-reactivity (2) but not clinical reactions to quail egg (QE) have been reported. Quail eggs are easy to buy in Italy and have been termed as appropriate for children suffering from HE allergy. We report a case of QE anaphylaxis in a child with HE allergy. D.G. is a 5-year-old boy, without a family history of allergic disease, born after a regular first pregnancy. He was breast-fed for 6 months and, after the fifth month, his feed included cow’s milk. At the age of 6 months, he developed atopic dermatitis and was diagnosed to be allergic to both cow’s milk and HE proteins. He was put on a diet without cow’s milk and HE until the age of 12 months. At that time, it was possible to include cow’s milk but not HE as he continued to show strong skin prick test (SPT) reactivity (>10 mm) to HE. From the age of 3 years, he developed allergic rhinitis and asthma episodes, mainly at home, during autumn. SPT and specific IgE showed dust mite sensitization (Table 1). Total IgE levels were 266 kU/ml. He was admitted to our hospital because of angio-edematous rash, rhinoconjunctivitis with edema of tarsal conjunctiva, wheezing and illness. These symptoms had arisen immediately after he had rubbed his face with his hand that had traces of QE and regressed in about 30 min after intramascular antihistaminic treatment and nebulized bronchodilator therapy. The child had never eaten any bird species nor had any pets or birds at home. The QE had been used for cooking, on the advice of the family doctor who did not consider QE dangerous in spite of the child’s HE allergy. Prick–prick tests (PPT) were strongly positive to both crude HE and QE white and yolk. SPT with HE white and yolk (Stallergenes S.A., Fresnes/Paris, France) as well as specific IgE for HE white and yolk (Pharmacia Upjohn AB, Uppsala, Sweden) were also strongly positive, while specific IgE for QE was not available. (Table 1). To evaluate if cutaneous cross-reactivity between HE and QE white and yolk was particular in this child or more common, we performed PPT with crude HE and QE egg white and yolk on 25 atopic children (mean age 47.8 months), 15 of who showed PPT positivity and allergy to HE. All children with PPT positive to egg white (n 1⁄4 15) and yolk (n 1⁄4 13) of HE showed positive PPT to QE also (for both egg white and yolk) and none of the children with negative PPT to HE showed PPT positive to QE (Spearman correlation 1.0; P < 0.0001).The SPT wheal mean diameter was 9.2 and 5.7 mm for HE white and yolk, 6.9 and 5.4 mm for QE white and yolk, respectively. Oral challenges with HE and QE were not carried out because of the lack of informed consent. We describe a child experiencing anaphylaxis at first contact with QE while reporting HE allergy. Furthermore, we show a strong correlation between HE and QE PPT positivity. Severe egg allergy by skin contact has been described (3) and wheezing has been possibly attributed to inhalation of egg proteins (4). As hen and quail belong to the same classification, Galliformes , this suggests the possible presence of crossreactive epitopes among the eggs of the two bird species and thus may explain the wide cross-reactivity, as already described for other bird eggs. In absence of oral challenges, we could not definitely establish clinical cross-reactivity between HE and QE. However, the child’s history, as well as the skin test correlations detected in the atopic group strongly recommend the avoidance of QE in children affected with HE allergy. AL LERGY 2 0 0 5 : 6 0 : 1 2 8 – 1 3 3 • COPYRIGHT a 2005 BLACKWELL MUNKSGAARD • ALL R IGHTS RESERVED • CONTRIBUT IONS TO THIS SECT ION WILL NOT UNDERGO PEER REV IEW, BUT WILL BE REV IEWED BY THE ASSOCIATE EDITORS •

The hygiene hypothesis proposes that declining exposure to infections may contribute to the allergy and asthma "epidemic", but studies to identify the infections involved have so far provided conflicting data. An alternative approach could be based on an attempt to identify the mechanisms common to several different infections, which may exert an atopy "protective" effect. One of these mechanisms may be fever, which is frequently associated with infections and may stimulate the synthesis of interferon-gamma. The aim of this study was to test whether the frequency of fever episodes in the first years of life are related to the development of atopy. Asthmatic (cases, n=317) and nonasthmatic children (controls, n=304) attending the outpatients' allergy clinic were enrolled. The number of fever episodes in the first 2 yrs of life was retrospectively assessed by parental report via a questionnaire completed by interview. Atopy was determined by skin-prick tests to 10 prevalent inhalant allergens at the time of examination. Fever episodes in the first or in the second year of life were significantly more frequent among children with asthma. However, this difference was totally accounted for by a subgroup of children who started wheezing in the first 12 months of life. A significant inverse association between fever episodes in the first 12 months of life and atopy was found among cases, but not in controls. The association persisted after adjusting for age, sex, daycare attendance and family history of atopic disease and this was totally accounted for by asthmatic children who started wheezing after the first 12 months of life. No significant association was found between fever episodes in the second year of life and atopy for cases and controls. The data presented here suggests that fever episodes early in life may affect the natural history of asthma by preventing the development of atopy and highlights the need to monitor fever episodes of any kind in longitudinal studies aimed at investigating the hygiene hypothesis prospectively.

Pyogenic abscess of the liver is uncommon child's pathology. The authors briefly describe a clinical picture characterized by beginning of an hepatic abscess dues to a germ that is not usually pathogen for men. It is often a mouth saprophyte.

Background IgE recognition of panallergens having highly conserved sequence regions, structure, and function and shared by inhalant and food allergen sources is often observed. Methods We evaluated the IgE recognition profile of profilins (Bet v 2, Cyn d 12, Hel a 2, Hev b 8, Mer a 1, Ole e 2, Par j 3, Phl p 12, Pho d 2), PR-10 proteins (Aln g 1, Api g 1, Bet v 1.0101, Bet v 1.0401, Cor a 1, Dau c 1 and Mal d 1.0108) and tropomyosins (Ani s 3, Der p 10, Hel as 1, Pen i 1, Pen m 1, Per a 7) using the Immuno-Solid phase Allergen Chip (ISAC) microarray system. The three panallergen groups were well represented among the allergenic molecules immobilized on the ISAC. Moreover, they are distributed in several taxonomical allergenic sources, either close or distant, and have a route of exposure being either inhalation or ingestion. Results 3,113 individuals (49.9% female) were selected on the basis of their reactivity to profilins, PR-10 or tropomyosins. 1,521 (48.8%) patients were reactive to profilins (77.6% Mer a 1 IgE+), 1,420 (45.6%) to PR-10 (92.5% Bet v 1 IgE+) and 632 (20.3%) to tropomyosins (68% Der p 10 IgE+). A significant direct relationship between different representative molecules within each group of panallergens was found. 2,688 patients (86.4%) recognized only one out of the three distinct groups of molecules as confirmed also by hierarchical clustering analysis. Conclusions Unless exposed to most of the allergens in the same or related allergenic sources, a preferential IgE response to distinct panallergens has been recorded. Allergen microarray IgE testing increases our knowledge of the IgE immune response and related epidemiological features within and between homologous molecules better describing the patients' immunological phenotypes.

Coeliac disease is the most frequent cause of chronic diarrhea (1:1000 children) in Italy. It often has atypical symptoms, so a sensitive and specific test is needed that can both simplify the ESPGAM criteria and monitor compliance of patients to their gluten free diet. The AEmA (anti endomysium antibody), found by Chorzelsky in 1984, appears to be a very sensitive and specific screening test in the diagnosis of coeliac disease (CD). Sera from 150 children, mean age 4 years (range 6 months to 20 years) were tested for endomysium antibodies (IgA class) and anti gliadin antibodies (IgG class). From our preliminary study IgA-AEmA seem to be more specific for CD than IgG class anti-gliaadin antibodies.

Identification, characterization, and purification of allergens are essential for the structural and immunologic studies needed to understand how these molecules induce specific IgE antibody production by the human immune system. Advances in molecular biology techniques have led to the production of recombinant allergens having constant properties, allowing detection of specific IgE directed against different molecular components of an allergenic source. Presence of homologous allergens in different sources is the reason for cross-reaction. Molecule-based diagnostic tools can lead to better interpretation of poly-sensitizations, observed by ST and in vitro tests using allergenic extracts as they were made before. Some examples IgE sensitization to major genuine allergens and panallergens will be presented.