Evaluation of two commercial peach extracts for skin prick testing in the diagnosis of hypersensitivity to lipid transfer protein. A multicenter study.

Summary: The clinical usefulness of two commercial peach extracts for SPT (by Lofarma SpA and ALK-Abellò, respectively) was compared in a multicenter study carried out in Italy. Peach allergic patients were tested with the two extracts in parallel and underwent the detection of IgE specific for all three peach allergens currently available (Pru p1, Pru p3, and Pru p4, respectively). The two extracts were almost identical in terms of sensitivity and specificity, being able to detect virtually all patients sensitized to stable peach allergens (lipid transfer protein (LTP) and, presumably, peamaclein) but scoring negative in patients exclusively sensitive to labile allergens (either PR-10 and/or profilin). Thus, the two extracts represent an excellent tool to carry out a preliminary component-resolved diagnosis of peach allergy at the first patient visit.

Sensitization to Gibberellin-Regulated Protein (Peamaclein) Among Italian Cypress Pollen-Sensitized Patients.

BACKGROUND AND OBJECTIVES: Peach gibberellin-regulated protein (peamaclein) has recently emerged as a relevant food allergen in cypress pollen-hypersensitive patients. Objective: We investigated monosensitization to peamaclein among Italian cypress pollen-allergic patients. MATERIAL AND METHODS: A total of 835 cypress pollen-hypersensitive patients from 28 Italian allergy centers underwent a thorough work-up to determine food-allergic reactions and performed skin prick testing with a commercial peach extract containing peamaclein. IgE to rPru p 3 was measured in peach reactors, and those with negative results were enrolled as potentially monosensitized to peamaclein. IgE reactivity to rPru p 7 was evaluated using immunoblot and an experimental ImmunoCAP with rPru p 7. RESULTS: Skin prick tests were positive to peach in 163 patients (19.5%); however, 127 (77.9%) were excluded because they reacted to Pru p 3. Twenty-four patients (14.7%) corresponding to 2.8% of the entire study population) were considered potentially monosensitized to peamaclein. No geographic preference was observed. Seventeen of the 24 patients (70.8%) had a history of food allergy, mainly to peach (n=15). Additional offending foods included other Rosaceae, citrus fruits, fig, melon, tree nuts, and kiwi. On peach immunoblot, only 3 of 18 putative peamaclein-allergic patients reacted to a band at about 7 kDa; an additional 4 patients reacted at about 50-60 kDa. Ten of 18 patients (56%) had a positive result for Pru p 7 on ImmunoCAP. CONCLUSION: Allergy and sensitization to peamaclein seem rare in Italy. Most patients react to peach, although other Rosaceae fruits and several citrus fruits may also be offending foods. Peach and cypress pollen probably also share cross-reacting allergens other than peamaclein.

Favorable Prognosis of Wheat Allergy in Adults.

BACKGROUND AND OBJECTIVE: Wheat ingestion can lead to disorders such as IgE-mediated food allergy and wheat-dependent exercise-induced anaphylaxis (WDEIA), both of which are associated with impaired quality of life and significant morbidity. Allergy to wheat is relatively benign in children, although its natural history in adults is still unknown. Objective: We used placebo-controlled challenge to evaluate the natural history of wheat hypersensitivity in atopic patients with adultonset wheat allergy. METHODS: We enrolled 13 patients from an initial cohort of adult patients with IgE-mediated wheat allergy (mean age, 40 years). After diagnosis, the patients observed a wheat-free diet and were followed as outpatients for 5 years to evaluate wheat exposure. Wheat-IgEtiters were determined at the end of follow-up, and a second wheat-challenge was performed. RESULTS: Ten out of 13 patients took part in the study. The mean period of wheat avoidance was 4.2 years. Three patients had spontaneously reintroduced wheat before the second evaluation, after a mean (IQR) of 28 (18-36) months, with only mild gastrointestinal discomfort at reintroduction. At the end of follow-up, 9 of the 10 patients were wheat-tolerant. Two patients had a history of WDEIA. We observed a reduction in IgE levels, with median (IQR) IgE falling from 2.77 (0.35-100) kU/L at diagnosis to 0.88 (0.1-20.8) kU/L. The association between IgE and a negative challenge result was not statistically significant. CONCLUSION: IgE-mediated wheat allergy in adults is benign and represents a temporary break in gastrointestinal tolerance. Future studies may improve our knowledge of wheat allergens, routes of and factors leading to sensitization, and prognostic biomarkers.

Hymenoptera Venom Allergy: Management of Children and Adults in Clinical Practice.

Hymenoptera venom allergy is an epidemiologically underestimated condition and a major cause of morbidity worldwide. Preventing future allergic reactions in patients who experience a systemic reaction is based on the correct management of the emergency followed by an accurate diagnosis, prescription of adrenaline autoinjectors, and, where indicated, specific venom immunotherapy. Some epidemiological studies highlight our poor knowledge of this disease and the frequent inadequacy of its management. Moreover, they emphasize the importance of such a life-saving treatment as specific immunotherapy. The availability of high-quality hymenoptera venom extracts for diagnostic and therapeutic use has dramatically improved the prognosis and quality of life of allergic patients. Subcutaneous venom immunotherapy is currently the most effective form of allergen-based immunotherapy, with a carry-over effect lasting up to several years after its interruption. This report on the management of hymenoptera venom-allergic children and adults was prepared by a panel of Italian experts. The main objective of this consensus document is to review the scientific evidence related to diagnosis, therapy, and management of patients allergic to hymenoptera venom. Thus, we can improve our knowledge of the disease and promote good clinical practices. The present document provides practical suggestions for correct diagnosis, prescription of emergency therapy and immunotherapy, and strategies for patient care.

Differences in chronic spontaneous urticaria between Europe and Central/South America: results of the multi-center real world AWARE study.

BACKGROUND: Global chronic urticaria (CU) disease experience and management is not well documented. This study descriptively compares these aspects among CU patients residing in Europe (EU) and Central and South America (C/SA). METHODS: AWARE (A World-wide Antihistamine-Refractory chronic urticaria patient Evaluation) is a global prospective, non-interventional study of CU in the real-world setting. Patients were ≥ 18 years with a diagnosis of H1-antihistamine-refractory CU for > 2 months. Differences between the EU and C/SA regions in demographic and clinical characteristics, quality of life (QoL), work and activity impairment, pharmacological treatment, and healthcare resource use were examined. RESULTS: In total, 4224 patients were included in the analysis (C/SA 492; EU 3732). Rates of untreated patients were greater in the C/SA region (45.1% vs. 31.9%; P < 0.005) and escalation to third-line therapy was rare in both regions. Differences in disease experience emerged, with C/SA patients more commonly experiencing angioedema (C/SA 50.8% vs. EU 46.1%; P = 0.03) or comorbid chronic inducible urticaria (C/SA 30% vs. EU 22%; P < 0.001). Correspondingly, rates of uncontrolled urticaria were higher among C/SA patients (82.8% vs. 77.5%; P = 0.017) and patients in the C/SA region showed significantly greater work and activity impairment (absenteeism: 10.4 ± 19.7 vs. 6.7 ± 19.0, P = 0.004; presenteeism: 30.3 ± 31.9 vs. 24.4 ± 25.8, P = 0.001; work productivity loss: 33.9 ± 33.9 vs. 26.5 ± 27.5, P < 0.001; activity impairment: 37.7 ± 34.7 vs. 32.7 ± 30.1, P = 0.001). However, QoL impairment was greater in the EU region (Dermatology Life Quality Index: C/SA 6.5 ± 5.9 vs. EU 8.3 ± 7.0; P < 0.001). There was a significant difference in use of healthcare resources, including emergency services (39.6% vs. 29.3%; P < 0.001), hospitalization (7.7% vs 21.9%; P < 0.001) general practitioners (31.7% vs 57.3%; P < 0.001), and additional allergists or dermatologists (50.6% vs. 47.3%, P < 0.001), among patients in the C/SA and EU region, respectively. In both regions, patients with a primary diagnosis of CU with angioedema had significantly greater impairment in work and non-work activities and healthcare resource utilization compared to those without angioedema. CONCLUSIONS: This study revealed that CU is a heterogeneous condition with differences in healthcare utilization and outcomes between EU and C/SA. However, overall there is a high unmet need of H1-antihistamine-refractory CU patients, which is associated with high use of healthcare resources, and has a large negative effect on QoL and work productivity.

EAACI Guidelines on Allergen Immunotherapy: Allergic rhinoconjunctivitis.

Allergic rhinoconjunctivitis (AR) is an allergic disorder of the nose and eyes affecting about a fifth of the general population. Symptoms of AR can be controlled with allergen avoidance measures and pharmacotherapy. However, many patients continue to have ongoing symptoms and an impaired quality of life; pharmacotherapy may also induce some side-effects. Allergen immunotherapy (AIT) represents the only currently available treatment that targets the underlying pathophysiology, and it may have a disease-modifying effect. Either the subcutaneous (SCIT) or sublingual (SLIT) routes may be used. This Guideline has been prepared by the European Academy of Allergy and Clinical Immunology's (EAACI) Taskforce on AIT for AR and is part of the EAACI presidential project "EAACI Guidelines on Allergen Immunotherapy." It aims to provide evidence-based clinical recommendations and has been informed by a formal systematic review and meta-analysis. Its generation has followed the Appraisal of Guidelines for Research and Evaluation (AGREE II) approach. The process included involvement of the full range of stakeholders. In general, broad evidence for the clinical efficacy of AIT for AR exists but a product-specific evaluation of evidence is recommended. In general, SCIT and SLIT are recommended for both seasonal and perennial AR for its short-term benefit. The strongest evidence for long-term benefit is documented for grass AIT (especially for the grass tablets) where long-term benefit is seen. To achieve long-term efficacy, it is recommended that a minimum of 3 years of therapy is used. Many gaps in the evidence base exist, particularly around long-term benefit and use in children.

Shrimp Allergy: Analysis of Commercially Available Extracts for In Vivo Diagnosis.

BACKGROUND AND OBJECTIVE: Skin prick testing (SPT) with commercial extracts is the first step in the diagnosis of shrimp allergy, although its clinical efficiency is unknown. Objective: To analyze the clinical usefulness of all commercial crustacean extracts available for SPT in Italy. METHODS: We performed a multicenter study of 157 shrimp-allergic patients who underwent SPT with 5 commercial crustacean extracts and with house dust mite (HDM) extract. Commercial extracts were analyzed using SDS-PAGE and compared with a freshly prepared in-house shrimp extract. IgE to Pen a 1/Pen m 1, Pen m 2, and Pen m 4 was determined, and immunoblot analysis was performed on a large number of sera. RESULTS: The skin reactions caused by commercial crustacean extracts were extremely heterogeneous, resulting in 32 clinical profiles, with marked differences in protein content and missing proteins at molecular weights corresponding to those of major shrimp allergens. Only strong Pen a 1/Pen m 1 reactors reacted to both HDM and all 5 commercial extracts in SPT. Most patients, including those who were tropomyosin-negative, reacted to HDM. Patients reacted to a large and variable array of proteins, and IgE reactivity was common at high molecular weights (>50 kDa). CONCLUSIONS: The in vivo diagnosis of shrimp allergy must continue to be based on SPT with fresh material. Shrimp-allergic patients frequently react to a number of ill-defined high-molecular-weight allergens, thus leaving currently available materials for component-resolved diagnosis largely insufficient. Mites and crustaceans probably share several allergens other than tropomyosin.

Clinical approach on challenge and desensitization procedures with aspirin in patients with ischemic heart disease and nonsteroidal anti-inflammatory drug hypersensitivity.

BACKGROUND: Hypersensitivity to acetylsalicylic acid (ASA) constitutes a serious problem for subjects with coronary artery disease. In such subjects, physicians have to choose the more appropriate procedure between challenge and desensitization. As the literature on this issue is sparse, this study aimed to establish in these subjects clinical criteria for eligibility for an ASA challenge and/or desensitization. METHODS: Collection and analysis of data on ASA challenges and desensitizations from 10 allergy centers, as well as consensus among the related physicians and an expert panel. RESULTS: Altogether, 310 subjects were assessed; 217 had histories of urticaria/angioedema, 50 of anaphylaxis, 26 of nonimmediate cutaneous eruptions, and 17 of bronchospasm related to ASA/nonsteroidal anti-inflammatory drugs (NSAID) intake. Specifically, 119 subjects had index reactions to ASA doses lower than 300 mg. Of the 310 subjects, 138 had an acute coronary syndrome (ACS), 101 of whom underwent desensitizations, whereas 172 suffered from a chronic ischemic heart disease (CIHD), 126 of whom underwent challenges. Overall, 163 subjects underwent challenges and 147 subjects underwent desensitizations; 86 of the latter had index reactions to ASA doses of 300 mg or less. Ten subjects reacted to challenges, seven at doses up to 500 mg, three at a cumulative dose of 110 mg. The desensitization failure rate was 1.4%. CONCLUSIONS: In patients with stable CIHD and histories of nonsevere hypersensitivity reactions to ASA/NSAIDs, an ASA challenge is advisable. Patients with an ACS and histories of hypersensitivity reactions to ASA, especially following doses lower than 100 mg, should directly undergo desensitization.

EAACI Molecular Allergology User's Guide.

The availability of allergen molecules ('components') from several protein families has advanced our understanding of immunoglobulin E (IgE)-mediated responses and enabled 'component-resolved diagnosis' (CRD). The European Academy of Allergy and Clinical Immunology (EAACI) Molecular Allergology User's Guide (MAUG) provides comprehensive information on important allergens and describes the diagnostic options using CRD. Part A of the EAACI MAUG introduces allergen molecules, families, composition of extracts, databases, and diagnostic IgE, skin, and basophil tests. Singleplex and multiplex IgE assays with components improve both sensitivity for low-abundance allergens and analytical specificity; IgE to individual allergens can yield information on clinical risks and distinguish cross-reactivity from true primary sensitization. Part B discusses the clinical and molecular aspects of IgE-mediated allergies to foods (including nuts, seeds, legumes, fruits, vegetables, cereal grains, milk, egg, meat, fish, and shellfish), inhalants (pollen, mold spores, mites, and animal dander), and Hymenoptera venom. Diagnostic algorithms and short case histories provide useful information for the clinical workup of allergic individuals targeted for CRD. Part C covers protein families containing ubiquitous, highly cross-reactive panallergens from plant (lipid transfer proteins, polcalcins, PR-10, profilins) and animal sources (lipocalins, parvalbumins, serum albumins, tropomyosins) and explains their diagnostic and clinical utility. Part D lists 100 important allergen molecules. In conclusion, IgE-mediated reactions and allergic diseases, including allergic rhinoconjunctivitis, asthma, food reactions, and insect sting reactions, are discussed from a novel molecular perspective. The EAACI MAUG documents the rapid progression of molecular allergology from basic research to its integration into clinical practice, a quantum leap in the management of allergic patients.

Hypersensitivity to Tomato (Lycopersicon esculentum) in Peach-Allergic Patients: rPrup 3 and rPrup 1 Are Predictive of Symptom Severity.

UNLABELLED: Background: The role of allergens in the severity of tomato allergy symptoms has not yet been studied. OBJECTIVES: To evaluate the relationship between severe allergic reactions to peach and tomato and between tomato allergy symptoms and the pattern of IgE positivity for rPru p 1, rPru p 3, rPru p 4, rBetv 1, rBetv 2, rBetv4, rPhl p 1, and rPhl p 12 in order to identify the role of recombinant allergens in the severity of reactions to tomato. METHODS: We studied peach-allergic patients with clinical reactions to tomato by performing an open food challenge, skin prick test, and determination of serum specific IgE to tomato and to recombinant peach, birch, and grass allergens. Statistical analysis was carried out to evaluate the relationship between the severity of tomato symptoms and IgE positivity to the different allergens and to peach-induced symptoms. RESULTS: We found a significant association between severe reactions to tomato and severe reactions to peach (P = .01 7) and levels of IgE to rPru p3 (P = .029) and between mild tomato allergy symptoms and levels of IgE to rPru p1 (P = .047), anti-rBetv 1 (P = .0414), anti-rBetv 2 (P = .0457), and Phleum pratense (P = .0022). CONCLUSION: We observed a significant relationship between peach and symptoms of tomato allergy. IgE positivity for rPru p3 seems to be a surrogate biochemical marker for severe tomato allergy, whereas the presence of anti-rPru p 1 IgE may be an indicator of mild tomato allergy.

Two cases of elevated tryptase in abdominal aortic aneurysm.

INTRODUCTION: From the literature, patients with a history of anaphylaxis to hymenoptera venom and positive specific IgE have shown a correlation between elevated tryptase levels and two clinical situations: systemic mastocytosis and an increased risk of reactions to venom immunotherapy or hymenoptera sting. Other clinical scenarios could explain elevated tryptase levels. MATERIAL AND METHODS: A 67 year old male (P1) and a 77 year old male (P2) were evaluated for previous severe anaphylaxis to hymenoptera sting. They underwent standard diagnostic work-up for hymenoptera venom allergy. Having found elevated tryptase levels, these were followed by a bone marrow biopsy to rule out systemic mastocytosis. RESULTS: P1: specific IgE and skin tests were positive for Vespula species; tryptase 52.8 ng/ml; P2: specific IgE and skin tests were positive for Vespa cabro and tryptase 153 ng/ml. Bone marrow biopsy results were negative for mastocytosis. We carried out magnetic resonance imaging, in P1 to better characterize the severe osteoporosis and in P2 because during physical examination a pulsating mass had been identified in the mesogastrium, and an aneurysm of the abdominal aorta which required surgical intervention in both patients was detected. Eight months after surgery, tryptase levels had diminished significantly (P1: 11.6 ng/ml and P2: 14.5 ng/ml). DISCUSSION: The elevated tryptase levels were correlated to abdominal aneurysm in both patients. In fact, post-surgery tryptase levels dramatically decreased. These two cases demonstrate that high tryptase levels in subjects with a history of hymenoptera venom anaphylaxis can be associated to undiagnosed aneurysmatic disease.

Baseline serum tryptase levels and adverse reactions to injection specific immunotherapy with airborne allergens: is there a relationship?

BACKGROUND: Elevated baseline serum tryptase levels are associated with severe systemic reactions following hymenoptera stings or venom immunotherapy. Little is known about baseline tryptase levels in patients with respiratory allergy and whether a relationship exists with systemic reactions induced by injection specific immunotherapy (SIT) with airborne allergens. The objective of this study was to measure tryptase levels in subjects with respiratory allergy and analyze the results in the light of tolerance/intolerance to injection SIT. METHODS: Baseline serum tryptase levels were measured in 106 adults allergic to different airborne allergens and in 40 normal controls. Thirty-one patients underwent injection SIT, and 15 of these 31 experienced at least one SIT-induced systemic reaction. RESULTS: Patients and normal controls showed similar median tryptase levels (2.98 vs. 3.13 ng/ml, respectively), although these were elevated in 6 patients (6%) versus 0 of 40 controls (0%). Tryptase levels did not differ between those patients with or without a history of systemic reactions (median 3.7 vs. 5.91 ng/ml, not significant). Three of 4 patients showing elevated tryptase levels belonged to the SIT-tolerant group. Elevated tryptase levels were not associated with specific allergens nor with distance from the specific pollen season. A bone marrow aspirate performed in the only patient with a history of systemic reactions following injection SIT and tryptase >11.4 ng/ml showed a normal morphology and phenotype. CONCLUSIONS: Unlike patients with hymenoptera venom allergy, in patients with respiratory allergy, elevated serum tryptase levels do not represent a risk factor for adverse reactions to SIT.

A study of HLA class I and class II 4-digit allele level in Stevens-Johnson syndrome and toxic epidermal necrolysis.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are represented by rare but life-threatening cutaneous adverse reactions to different drugs. Previous studies have found that in a Han Chinese population from Taiwan and other Asian Countries, a strong genetic association between HLA-class I alleles (B*15:02, B*58:01) and SJS and TEN was induced by carbamazepine and allopurinol, respectively. To identify genetic markers that covered the MHC region, we carried out a case-control association enrolling 20 Caucasian patients with SJS/TEN. Our patient series included 10 cases related to paracetamol, 7 to allopurinol and 3 to different drugs (plaquenil, itraconazol, nabumetone). Healthy controls were represented by 115 Caucasian bone marrow or stem cell donors. The HLA-A*, B*, C*, DRB1*, DQB1*, DQA1* and DPB1* genotyping were determined. The frequencies of HLA-A*33:03 as well as C*03:02 and C*08:01 were significantly higher in SJS/TEN patient subgroup showing allopurinol drug-induced severe cutaneous adverse reactions (SCAR) as compared to controls (28.6% vs 0%, P=0.00002, Pc=0.0011; 28.6% vs 0%, P=0.00002, Pc=0.001; 28.6% vs 0%, P=0.00002, Pc=0.001, respectively). In the same subgroup the frequencies of B*58:01, DRB1*15:02 and DRB1*13:02 alleles, although considerably higher than in control group (42.8% vs 5.2%, P=0.003; 28.6% vs 1.7%, P=0.005; 28.6% vs 3.5%, P=0.037, respectively), appeared no more statistically different after P correction (Pc=0.248; Pc=0.29; Pc=1.00, respectively). In addition, in 10 of the 20 SJS/TEN patient subgroup with paracetamol-induced SCAR no statistically significant association with HLA alleles could be found. However, in the same SJS/TEN patient subgroup showing allopurinol drug-induced SCAR, haplotype analysis indicated that B*58:01, DRB1*13:02 and DRB1*15:02 alleles, that in a single allele analysis lost statistical significance after P correction, may still confer susceptibility, because the B*58:01-DRB1*13:02 and DRB1*15:02-DQB1*05:02 are positively associated with the disease (14.2% vs 0.43%, P= 0.00001, Pc=0.00028; 14.2% vs 0.43%, P=0.00001, Pc=0.00028, respectively). Our results show that in contrast to SCAR-related to paracetamol, where HLA alleles do not appear to be involved, HLA molecules behave as a strong risk factor for SCAR-related to allopurinol even when a limited number of patients are considered.

Characterization of the T-cell epitopes of the major peach allergen Pru p 3.

BACKGROUND: Pru p 3 is the major peach allergen recognized by more than 90% of peach-allergic individuals of the Mediterranean area. Identification of the dominant Pru p 3 T-cell epitopes can improve our understanding of the immune responses against this protein and could be helpful in the development of hypoallergenic immunotherapy. For this purpose, we examined the phenotypes, specificities and cytokine secretion profiles of proliferating T cells in response to Pru p 3 in peach-allergic individuals. METHODS: Peripheral blood mononuclear cells from 15 peach-allergic patients were incubated with Pru p 3. The proliferation of antigen-specific T-cell lines (TCLs) was assessed by tritiated methylthymidine incorporation. T-cell epitopes were identified by analyzing the reactivity of TCLs against 8 overlapping peptides spanning the entire length of Pru p 3. We characterized the phenotype of Pru-p-3-specific TCLs by flow cytometry and analyzed their production of interleukin (IL) 4 and gamma-interferon (IFN-gamma) by ELISA. RESULTS: Ninety-two Pru-p-3-specific TCLs were isolated (stimulation index > or =5). These TCLs proliferated mainly in response to Pru p 3(12-27) and Pru p 3(57-72). Pru-p-3-specific TCLs were mainly CD4+ (81%) and expressed cell surface CD30. In addition, TCLs produced high levels of IL-4 and low levels of IFN-gamma, indicating a Th2 phenotype. CONCLUSIONS: Two immunodominant T-cell-reactive regions of Pru p 3 were identified: Pru p 3(12-27) and Pru p 3(57-72). These peptides showed a differential ability to elicit a Th2 response. Taken together, our results provide a better understanding of the immunological T-cell reactivity against Pru p 3.

Maize food allergy: a double-blind placebo-controlled study.

BACKGROUND: Maize allergy is not very common especially in Europe. The number of studies that address IgE mediated maize allergy is all too few. OBJECTIVE: Evaluate subjects with a history of maize allergy by double-blind, placebo-controlled food challenge; identify the spectrum of symptoms manifested during challenge; determine the lowest provocation dose (PD) during challenge; determine the performance characteristics of maize skin prick test and specific IgE. METHODS: Twenty-seven patients with a history of maize allergy were enrolled to be evaluated by skin test, specific IgE and double-blind placebo-controlled maize challenge. RESULTS: Forty-eight percent of the patients were challenge positive. PD range was 0.1-25 g. Fifty-four percent of the maize allergic subjects had a PD that was < or = 2.5 g; two subjects reacted to 100 mg of maize. Comparison of maize specific IgE levels and skin test results to the challenge results revealed the following (specific IgE level/skin testing): sensitivity 1.00/0.846, specificity 0.077/0.384, positive predictive value 0.520/0.579, and negative predictive value 1.00/0.714. CONCLUSION: Maize is a cause of IgE-mediated allergic reactions to foods in adults and children. Nearly half of the subjects recruited were confirmed by challenge to be allergic to maize. Twenty-three percent of the positive challenge patients manifested symptoms that involved two organ systems, thus fulfilling the criteria for maize induced anaphylaxis. Maize is allergenic and can pose a risk for symptomatic food allergy at a dose of 100 mg.

Influence of cultivar and processing on cherry (Prunus avium) allergenicity.

Oral allergy syndrome is an immediate food allergic event that affects lips, mouth, and pharynx, is often triggered by fruits and vegetables, and may be associated with pollinosis. Here, we report on the allergenic pattern of different varieties of cherry (Prunus avium) and results obtained by applying several technological processes to the selected varieties. Whole cherries were submitted to chemical peeling, thermal treatment, and syruping processes, and the relative protein extracts were analyzed by in vitro (sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting analysis) and in vivo tests (skin prick test). Electrophoretic analyses demonstrated that there was no marked difference among cherry cultivars. Chemical peeling successfully removed Pru av 3, a lipid transfer protein (LTP) responsible for oral allergy syndrome in patients without pollinosis, leading to the industrial production of cherry hypoallergenic derivatives. Furthermore, the syruping process removed almost all allergenic proteins to whom patients with pollinosis are responsive. In vivo tests confirmed electrophoretic results.

Screening the allergenic repertoires of wheat and maize with sera from double-blind, placebo-controlled food challenge positive patients.

BACKGROUND: Food allergy to wheat and maize is an increasing factor of deterioration of life quality, especially childhood and can, in rare cases, even induce anaphylaxis. Although omega-5 gliadin from wheat and maize lipid transfer protein have been characterized as major cereal allergens on the molecular level, the list of food allergens is far to be complete. METHODS: To identify the IgE-binding repertoires of wheat and maize we screened respective cDNA libraries displayed on phage surface with sera from patients with a confirmed food allergy. The study included six patients with a positive double-blind, placebo-controlled food challenge (DBPCFC) to wheat, nine patients with a positive DBPCFC to maize, and six patients with anaphylactic reactions after ingestion of wheat. RESULTS: The enriched sequences encoding IgE-binding proteins showed heterogeneous repertoires for both, wheat and maize. The selected wheat repertoire yielded 12, the maize repertoire 11 open reading frames. Among these we identified allergens belonging to already characterized allergens families, such as gliadin, profilin and beta-expansin. Besides, we found novel proteins with high cross-reactive potential, such as thioredoxins, as well as sequences that had so far not been related to cereal allergy at all. The IgE-binding capacity of some selected proteins was evaluated in vitro and cross-reactivity was demonstrated by competition ELISA. CONCLUSION: With regard to the heterogeneity of the characterized sequences as well as to the biochemical nature of the new allergens detected we conclude that wheat and maize-related food allergy is more complex than so far anticipated.