IgE-binding Components Research Articles

Immunological Cross-Reactivity Involving Mollusc Species and Mite-Mollusc and Cross-Reactive Allergen PM Are Risk Factors of Mollusc Allergy.

Marine molluscs are seafood consumed worldwide and could cause food allergies, while investigation on their sensitizing components and cross-reactivity seems to be rare. Furthermore, allergy to mites may result in anaphylaxis in mollusc-allergic individuals owing to their cross-reactivity. The aim of the study was to identify cross-reactive allergens and investigate the cross-reactivity between different mollusc groups and mite-mollusc. The extracted mollusc and dust mite proteins were separated by SDS-PAGE, and IgE-binding components were recognized by immunoblotting with sera from patients sensitized to mollusc and mite. Cross-reactivity of different mollusc groups and mite-mollusc was assessed using ELISA and inhibition ELISA. The results of the immune detection, ELISA, and inhibition ELISA indicated that different mollusc groups and mite-mollusc showed varying degrees of cross-reactivity. The most frequently recognized cross-reactive protein was paramyosin from different mollusc groups and dust mite, while cross-reactive allergen paramyosin in the mite extract was identified and evaluated by MS and Allermatch, respectively. Inhibition ELISA studies also revealed that paramyosin played an important role in molluscan and mite-molluscan cross-reactivity. These findings contribute to a better understanding of the cross-reactivity involving mollusc species and mite-mollusc, which can be used to assist in the diagnosis and treatment of mite- and mollusc-allergic disorders.

Allergen components of Dermatophagoides farinae recognised by serum immunoglobulin (Ig)E in Thai dogs with atopic dermatitis

Dermatophagoides farinae (Der f) is a common allergen in dogs with atopic dermatitis (AD). However, the relevant components of Der f require further investigation. We aimed to provide data on the immunoglobulin (Ig)E-binding specific components of Der f for further diagnostic and therapeutic applications. Serum samples were collected from five healthy, nine Der f-allergic atopic and seven non-Der f-allergic atopic dogs identified based on an intradermal skin test. We explored the component profiles of Der f extracts through 2D gel electrophoresis and IgE immunoblotting. The IgE-binding components in both groups of atopic dogs were analysed by mass spectrometry. The majority of Der f-allergic atopic dogs recognised Der f Alternaria alternata allergen 10 (Der f Alt a 10), elongation factor 1-alpha (EF1-α), gelsolin-like allergen Der f 16, Der f 28 and Der f 2. Der f 3, Der f 10, Der f 20 and Der f 32 were recognised as minor allergens. Alpha-enolase, serine protease, arginine kinase and a few hypothetical proteins were recognised components in both groups of atopic dogs. Unexpectedly, Der f 15 (chitinase) was found to be a minor component. Multiple IgE-binding allergens of Der f were identified in Thai atopic dogs. We propose that the specific antigen set that is bound by IgE, comprising Der f Alt a 10, EF1-α, gelsolin-like Der f 16, Der f 28 and Der f 2, could be used for future diagnostics and immunotherapy platforms.

Identification the Cross-Reactive or Species-Specific Allergens of Tyrophagus putrescentiae and Development Molecular Diagnostic Kits for Allergic Diseases.

Mite allergens are considerable factors in the genesis of allergic diseases. The storage mite Tyrophagus putrescentiae (Tp) appears in contaminated foods and household surroundings. The current diagnostic tools for Tp allergy are mostly based on crude extracts and still contain shortcomings. This study aimed to investigate the immunoglobulin E (IgE)- responsiveness profiles of Tp-allergic patients and develop a molecular diagnostic method using recombinant allergens. Allergenic components were characterized as cross-reacting or species-specific allergens, in which the effective combinations of recombinant allergens were developed and analyzed in terms of the prediction accuracy for clinical diagnosis. Seven recombinant allergens were cloned and generated to detect the IgE responsiveness of the Tp allergy. A survey on the prevalence of mite allergy showed there were higher sensitizations with IgE responsiveness to house dust mites (HDM) (78.9–80.9%) than to storage mites Tp (35.6%). Prevalence of sensitization to Tp was higher in elderly subjects. The principal IgE-binding components of Tp were Tyr p 1, Tyr p 2 and Tyr p 3. Prediction accuracy for Tp allergy by IgE-responsiveness combination D (Tyr p 1, Tyr p 2 & Tyr p 3) was with high precision (100%). Avoiding the cross-reactivity of Dermatophagoides pteronyssinus, the prediction accuracy of IgE-responsiveness combination H+ (Tyr p 1, Tyr p 2, Tyr p 3, Tyr p 7, Tyr p 8, Tyr p 10 & Tyr p 20) was suitable for Tp-specific diagnosis. Panels of Tp allergens were generated and developed a diagnostic kit able beneficial to identify IgE-mediated Tp hypersensitivity.

Towards complete identification of allergens in Jack Jumper (Myrmecia pilosula) ant venom and their clinical relevance: An immunoproteomic approach.

The venomous stings of Jack Jumper ant (JJA; species of the Myrmecia pilosula taxonomic group) are a significant public health issue in parts of south-eastern and south-western Australia, causing anaphylaxis in approximately 3% of the population. Three allergenic peptides, Myr p 1, Myr p 2 and Myr p 3, and one histamine-releasing peptide, pilosulin 5, have been fully described, but there are at least 5 additional high molecular weight IgE-binding components that have not been identified. To identify IgE-binding components in JJA venom (JJAV) and to relate the IgE recognition of these components to relevant clinical parameters. Identification of IgE-binding components and determination of their sensitizing prevalence was performed using SDS-PAGE immunoblot assay and sera from 90 patients with confirmed allergy to JJAV. Tandem mass spectrometry was used for identification of novel JJAV components fractionated by size exclusion chromatography (SEC) and SDS-PAGE. Using SDS-PAGE immunoblot, 10 IgE-binding bands were identified in JJAV, two of which were recognized by 81% and 47% of the population studied. Mass spectrometry identified 17 novel JJAV proteins, including 2 glycoproteins, and confirmed the presence of 4 known Myr p and pilosulin peptides in JJAV. Most of the newly identified IgE-binding proteins were enzymes, including phospholipase A2 , hyaluronidase, arginine kinase and dipeptidyl peptidase IV. Correlations were found between recognition of certain IgE-binding bands with JJAV-specific IgE titre by ImmunoCAP, intradermal test threshold and treatment-related issues. This study has for the first time revealed the identity of various proteins with IgE-binding capacity in the venom of JJA and demonstrated their clinical relevance in the diagnosis and treatment of JJAV allergy.

Parasite allergens

Human IgE against helminths is a normal component of the whole protective response elicitesd during infection, when specific IgE to a great number of antigens is produced; however, few of those IgE binding components are actually allergens. In general, considering the strong Th2/IgE responses during helminth infections is intriguing that they are not usually associated with allergic symptoms, which probably (but not exclusively) depends on parasite-induced immunomodulation. However, allergic manifestations have been described during some helminth infections such as ascariasis, strongyloidiasis, anisakiasis and hydatidosis. In addition, there is evidence that helminthiases (e.g. ascariasis) can increase symptoms in allergic patients. Furthermore, allergic reactions during anti-helminth vaccination have been observed, a problem that also could be associated to the future use of parasite derived immunomodulators. Therefore, identification and characterization of helminth allergens is a matter of increasing research and a great number of IgE binding antigens have been found (www.allergen.org and www.allergome.org). Here we describe only a small group of them, for which allergenic activity (the ability to induce IgE mediated inflammation) have been clinical or experimentally demonstrated. Ascaris lumbricoides tropomyosin (Asc l 3) has strong allergenic activity; in the Tropics it has been associated with asthma and asthma severity, suggesting clinical relevance. In addition, due to its cross reactivity with mite tropomyosins this allergen could influence house dust mite (HDM) allergy diagnosis. Characterized Ascaris allergens also include the polyprotein As s 1 (ABA-1) and the Glutathione transferase As l 13. Other helminth allergens include Anisakis simplex Ani s 1, Ani s 4, Ani s 7 and Ani s 9; Necator americanus NaASP2q and Nacal1 and Schistosoma mansoni SmVAL4 and Sm22.6. Future work on helminth IgE binding antigens will help to understand several aspects of allergenicity and allergenic activity, among them the increasing finding of IgE binding molecules that not induce allergic symptoms.

Solenopsis geminata (tropical fire ant) anaphylaxis among Thai patients: its allergens and specific IgE-reactivity.

Specific IgE against Solenopsis invicta (imported fire ant) remains the current diagnostic tool for allergy to ants worldwide. However, S. invicta may not be the only cause of ant anaphylaxis in Thai patients. To characterize ant species causing anaphylaxis in Thai patients and to test allergenic reactivity to whole body extracts (WBE) of S. geminata (tropical fire ants) in patients with evidence of IgE-mediated ant anaphylaxis. Thirty-two patients with ant anaphylaxis were identified. The causative ants collected by the patients were subjected to species identification. Twelve patients with ant anaphylaxis and showed positive skin test or serum specific IgE to S. invicta and 14 control subjects were recruited. Whole body extraction from S. geminata was performed for protein characterization using SDS-PAGE and protein staining. IgE-immunoblotting and ELISA-specific IgE binding assays were performed on patients' sera and compared with controls. Of 32 patients with ant anaphylaxis, the most common causative ant identified was S. geminata (37.5%). Western blot analysis of crude S. geminata revealed 13 refined protein components that bound to patients' serum IgE. Three major allergens with molecular masses of 26, 55 and 75 kDa were identified. All 12 patients gave positive results for specific IgE to S. geminata with statistically significant higher absorbance units of 0.390 ± 0.044, compared to healthy control group (0.121 ± 0.010), P < 0.01. S. geminata is identified as the most common causative ant anaphylaxis in Thai patients. Its WBE comprises of 13 IgE-binding components and 3 major allergens (26, 55 and 75 kDa), which supported possible IgE-mediated mechanism.

Comparison of IgE-binding components between 2 house dust mites in adult allergic patients

Purpose: This study investigated the differences in the profile of IgE-binding components between Dermatophagoides pteronyssinus (Dp) and Dermatophagoides farina (Df) in respiratory allergic patients sensitized to Dp/Df. Methods: Eighteen patients with respiratory allergic diseases having higher levels of serum specific IgE to Df compared to those to Dp (> twice) were enrolled. IgE-immunoblot analysis using Dp and Df extracts were used to compare the IgE binding components. Study subjects were classified into 2 groups according to the results of IgE-immunoblot analysis: 6 subjects having IgE-binding components to group 1 and 2 allergens (group B) and 12 subjects not having them (group A). Results: Group A subjects were older (47.92± 8.51 vs. 35.50± 11.10, P = 0.039) and males were dominant (75% vs. 0% P = 0.009). IgEimmunoblot analysis demonstrated that all the group B subjects had IgE bindings to 2 major components, 14 and 25 kDa, while group A subjects had IgE bindings to high-molecular weight components ranging from 60–98 kDa. The enzyme-linked immunosorbent assay inhibition test showed a significant inhibition with additions of Df, not with Dp in group B subjects. Serum specific IgE levels to Dp and Df were significantly higher in group B than in group A, while its ratio (Df to Dp) was significantly higher in group A. No differences were noted in clinical parameters, total IgE, or eosinophil cationic protein levels. Conclusion: Heterogeneity of IgE binding patterns to Dp and Df extracts was noted according to the ratio of serum specific IgE (Df/ Dp). (Allergy Asthma Respir Dis 2016;4:199-204)

Vacuolar Serine Protease Is a Major Allergen of Fusarium proliferatum and an IgE-Cross Reactive Pan-Fungal Allergen.

PurposeFusarium species are among prevalent airborne fungi and causative agents of human respiratory atopic disorders. We previously identified a 36.5-kDa F. proliferatum component recognized by IgE antibodies in 9 (53%) of the 17 F. proliferatum-sensitized atopic serum samples. The purpose of this study is to characterize the 36.5-kDa allergen of F. proliferatum.MethodsCharacterization of allergens and determination of IgE cross-reactivity were performed by cDNA cloning/expression and immunoblot inhibition studies.ResultsBased on the finding that the 36.5-kDa IgE-binding component reacted with the mouse monoclonal antibody FUM20 against fungal vacuolar serine protease allergens, the cDNA of F. proliferatum vacuolar serine protease (Fus p 9.0101) was subsequently cloned. Nine serum samples from respiratory atopic patients with IgE binding to the vacuolar serine protease allergen of Penicillium chrysogenum (Pen ch 18) also showed IgE-immunoblot reactivity to rFus p 9.0101. The purified rFus p 9.0101 can inhibit IgE and FUM20 binding to the 36.5-kDa component of F. proliferatum. Thus, a novel and important Fus p 9.0101 was identified. The rPen ch 18 can inhibit IgE binding to Fus p 9.0101. It indicates that IgE cross-reactivity between Fus p 9.0101 and Pen ch 18 also exists. Furthermore, neither rFus p 9.0101 K88A nor rPen ch 18 K89A mutants inhibited IgE binding to rFus p 9.0101. Lys88 was considered a critical core amino acid in IgE binding to r Fus p 9.0101 and a residue responsible for IgE cross-reactivity between Fus p 9.0101 and Pen ch 18 allergens.ConclusionsResults obtained from this study indicate that vacuolar serine protease may be a major allergen of F. proliferatum and an important IgE cross-reactive pan-fungal allergen, and provide important bases for clinical diagnosis of fungal allergy.

Two new types of allergens from the cockroach, Periplaneta americana.

Periplaneta americana cockroach is an important source of inhalant indoor allergen resource, and there are more than twenty IgE-binding components identified in P. americana, but only nine allergens were characterized. Our knowledge about cockroach allergens remains poor. In this work, two novel allergen proteins Per a 11 (alpha-amylase) and Per a 12 (chitinase) with molecular weight around 55 and 45 kDa, respectively, were purified and characterized from the midgut of cockroaches. Their primary sequences were determined by Edman degradation, mass spectrometry, and cDNA cloning. Sera from 39 and 30 of 47 (83.0% and 63.8%) patients reacted to Per a 11 and Per a 12 on immunoblots, respectively. The allergenicity of Per a 11 and Per a 12 was further confirmed by competitive ELISA, basophil activation test (BAT), and skin prick test (SPT). They appear to be of importance for the allergic reactions induced by cockroach and have a potential for component-based diagnosis of allergy.

IgE- and T-lymphocyte-Dependent Hypersensitivity Responses Induced in Mice by Exposure to Shrimp (Fenneropenaeus chinensis) Proteins

Shellfish allergy is a common cause of food-induced anaphylaxis in the human, and shrimp is one of the most frequently reported causes of allergic reactions. To identify the immunoglobulin E (IgE)-binding proteins of Chinese shrimp (Fenneropenaeus chinensis), the crude extracts were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS–PAGE) and Western blotting. After exposure of shrimp extracts to mice, the levels of shrimp allergen-specific IgE were determined by indirect ELISA. Histological and immunohistochemical staining of intestinal tract were further performed for immunological analysis. IgE-binding components with molecular masses of 40, 37, 28, 22, and 20 kDa at a high frequency are supposed to be major allergens of F. chinensis. In vivo experiments showed that shrimp extracts could lead to allergen-specific IgE reactivity, and increase mast cell degranulation and numbers of T lymphocytes. IgE- and T-lymphocyte-dependent hypersensitivity plays important roles in allergic reactions triggered by F. chinensis allergens.

An IgE-Mediated Allergic Reaction Caused by Mulberry Fruit.

Mulberry (Morus spp.) is a widespread deciduous tree and its fruit is commonly eaten in Korea and eastern Asia. Some reports demonstrate that mulberry fruit is a food allergen in the Mediterranean area. However, there has been no report of systemic allergic reactions after ingesting mulberry fruit in Korea. An 18-year-old boy with a mulberry fruit allergy visited our allergy clinic. He had experienced generalized urticaria, chest tightness, breathing difficulty, and abdominal cramping after ingesting mulberry fruit. The patient had a positive skin reaction to mulberry fruit extract (mean wheal size, 5 mm). We performed an ELISA to detect specific IgE antibody (Ab) to mulberry fruit extract in the patient's serum compared to those of non-atopic healthy controls and birch-sensitized individuals. Specific IgE Ab to mulberry fruit extract was detected in the patient's serum, as compared to non-atopic healthy controls. Another subject, who was strongly sensitized to birch pollen, also had a positive serum-specific IgE Ab to mulberry fruit. We performed IgE immunoblot analysis using the patient's and the other subject's sera, who had serum-specific IgE to mulberry fruit, to identify the IgE-binding component. An identical IgE-binding component to mulberry extract was detected in the two subjects at around 17 kDa, and which might be PR 10 of Bet v 1. In conclusion, mulberry fruit could induce a systemic allergic reaction through an IgE-mediated mechanism, and cross-reactivity might occur between mulberry fruit and birch pollen.

The transaldolase, a novel allergen of Fusarium proliferatum, demonstrates IgE cross-reactivity with its human analogue.

Fusarium species are among airborne fungi and recognized as causative agents of human atopic disorders. However, Fusarium allergens have not been well characterized and the lack of information limits clinical diagnosis and treatment of fungal allergy. The purpose of this study is to identify and characterize important allergens of F. proliferatum. IgE-reacting F. proliferatum components were identified by immunoblot using serum samples from patients of respiratory atopic diseases. Characterization of allergens and determination of IgE cross-reactivity were performed by cDNA cloning, then homologous expression and immunoblot inhibition studies. We identified nine different F. proliferatum components that can be recognized by IgE antibodies in 17 (28%) of the 60 atopic sera tested. Components with molecular masses of about 43, 37.5 and 36.5 kDa with IgE-binding frequencies of about 88, 47 and 53%, respectively, were considered as important allergens of F. proliferatum. The 37.5 kDa IgE-binding component was putatively considered as a transaldolase protein of F. proliferatum. The full-length cDNA of F. proliferatum transaldolase was subsequently cloned. It encodes an open reading frame of 312 amino acids and has sequence identifies of 73 and 61%, respectively, with Cladosporium and human transaldolases. The purified recombinant F. proliferatum transaldolase can inhibit the IgE-binding against the 37.5 kDa component of F. proliferatum and the transaldolase allergen from Cladosporium cladosporioides. More importantly, the recombinant F. proliferatum transaldolase can inhibit IgE-binding against human transaldolase in a concentration-dependent manner. Thus, a novel and important F. proliferatum transaldolase allergen was identified. In addition to IgE cross-reactivity between the Fusarium and the Cladosporium transaldolase allergens, IgE cross-reactivity between the Fusarium and the human transaldolases also exists and might contribute to atopic manifestations in the absence of exogenous allergen exposure.

Environmental changes could enhance the biological effect of Hop J pollens on human airway epithelial cells

Environmental changes could enhance the biological effect of Hop J pollens on human airway epithelial cells

Detection of IgE binding component to infliximab in a patient with infliximab-induced anaphylaxis

Detection of IgE binding component to infliximab in a patient with infliximab-induced anaphylaxis

Paradoxical Increase of IgE Binding Components during Allergen-Specific Immunotherapy in Pollinosis Patients

Allergen-specific immunotherapy (SIT) reduces allergen specific IgE (sIgE) levels and achieves clinical and immunological tolerance by modulating innate and adaptive immunological responses. Increased temperature and CO2 concentrations caused by climate changes contribute to an increase of pollen count and allergenicity that influences clinical SIT outcomes. In this study, we investigated the changes of IgE binding components to tree and weed pollens in pollinosis patients who showed a paradoxical increase of serum sIgE level during pollen-SIT. We enrolled nine patients who showed an increasing pattern of serum sIgE level to alder, birch, ragweed and mugwort pollens by enzyme-linked immunosorbant assay. IgE immunoblot analysis confirmed the intensification or new generation of major IgE binding components that could be induced by climate change. The findings suggest that the regular monitoring of sIgE levels and symptom changes is required to improve the clinical outcomes of SIT in patients undergoing SIT for tree and weed pollens.Graphical

Identification of IgE binding components of two major weed pollens, ragweed and mugwort

Purpose: We investigated the causes, clinical features, and risk factors of bee venom anaphylaxis in Korea. Methods: The medical records of the diagnosis of anaphylaxis during a 5-year period from the 14 hospitals in Korea have been retrospectively reviewed. Cases of bee venom anaphylaxis were identified among anaphylaxis patients, and subgroup analyses were done. Results: A total of 291 patients were included. The common cause of bee species was vespid (24.6%) in bee venom anaphylaxis, followed by honeybee and vespid (8.8%), apitherapy (7.7%), and honeybee (2.0%), although the causative bee species were commonly unknown (56.9%). The severity of anaphylaxis was mostly mild-moderate (72.9%), and common clinical manifestations included cutaneous (80.6%), cardiovascular (39.2%), respiratory (38.1%), and gastrointestinal (13.1%) symptoms. Portable epinephrine auto-injectors were prescribed to 12.1% of the patients. Subject positive to both vespid and honeybee showed more severe symptoms and higher epinephrine use (P<0.05). The severity was significantly associated with older age, but not with gender, underlying allergic disease, or family history. Apitherapy-induced anaphylaxis showed a higher rate of hospitalization and epinephrine use than bee sting anaphylaxis (P<0.05). Conclusion: Vespid is the most common cause of bee venom anaphylaxis in Korea. It is suggested that positivity to honeybee and vespid may be associated with more severe symptoms. (Allergy Asthma Respir Dis 2014;2:344-351)

IgE reactivity to Acarus siro extract in Korean dust mite allergic patients

Although specific IgE to the storage mite Acarus siro is often detected, there are no detailed studies on IgE reactivity to A. siro in Korea. This study was undertaken to investigate the cross-reactivity to the mite species Dermatophagoides pteronyssinus, Dermatophagoides farinae, Tyrophagus putrescentiae, and A. siro in Korean mite allergic patients. Specific IgE values were determined for the four mite species and a competitive inhibition test was performed for mite extracts using the ImmunoCAP system. The IgE value to D. farinae was the highest among the four mite species tested. There was a strong correlation in the IgE value between house dust mites (D. pteronyssinus and D. farinae) and between storage mites (A. siro and T. putrescentiae). IgE reactivity to A. siro was inhibited by D. farinae and T. putrescentiae extract. Dermatophagoides farinae extract was the strongest inhibitor of IgE binding to A. siro extract, indicating that IgE reactivity to A. siro extract is a cross-reaction caused by sensitization to D. farinae. Strong IgE reactive components were observed in D. farinae and T. putrescentiae extract by SDS-PAGE and IgE immunoblotting. However, no strong IgE-binding component was observed for A. siro. Dermatophagoides farinae is the main source of mite allergens that cause sensitization in Korea. Serum IgE from some of the house dust mite-sensitized patients showed positive responses to storage mite allergens by cross-reaction. Therefore, it is necessary to pay special attention to the diagnosis of mite allergies.

Moving from peanut extract to peanut components: towards validation of component‐resolved IgE tests

Replacement of peanut extracts by recombinant peanut components is an important step in allergy serologic testing. Criteria are needed for the unbiased inclusion of patients into a study to validate such a replacement. Plasma samples from 64 peanut-positive children (42 reactors, 22 nonreactors in a double-blind, placebo-controlled food challenge) were used to compare IgE reactivity to six recombinant peanut allergens with reactivity to natural peanut proteins extracted at neutral or low pH. We tested the hypothesis that poor extractability of Ara h 9 and other basic allergens at neutral pH leads to under-representation of patients with such sensitization. IgE reactivity to the components did not fully explain IgE reactivity to peanut extract in 5 of 32 reactors with IgE to peanut extract ≤100kUA /l. IgE reactivity to components was stronger than to the extract in 11 plasma samples, which was largely due to a low Ara h 8 reactivity of the extract. IgE reactivity to Ara h 9 was much lower than reactivity to other basic proteins, some of which bound IgE well in the RAST, but lost IgE reactivity upon immunoblotting. Conventional peanut extracts are deficient in significant IgE-binding components. The inclusion of patients for a validation study should be based on serology performed with improved peanut reagents to avoid a bias against these under-represented, potentially important allergens. To judge clinical relevance of an allergen, the reagent used for inclusion of patients needs to be efficient in detecting IgE to this component.

Phytohemagglutinins augment red kidney bean (Phaseolus vulgaris L.) induced allergic manifestations

Red kidney bean (Phaseolus vulgaris L.), a commonly consumed bean has been reported to induce allergic reactions in susceptible individuals. Phytohemagglutinins (PHAs, mainly PHA-P) contribute a major proportion of red kidney bean seeds. However, their roles in red kidney bean induced allergic reactions are still to be explored. This study was carried out to understand the role of PHAs in allergic manifestations using BALB/c mice and cultures of splenocyte, RBL-2H3 cells as well as bone marrow mast cells (BMMCs). Also, the characterization of allergic components from PHA-P was studied by LC-MS/MS. Enhanced levels of specific IgE and IgG1, clinical scores, cytokines and chemokines, β-hexosaminidase, histamine, cysteinyl leukotriene, prostaglandin D2 and abrupt histological changes in the intestine, lung and spleen indicated a pivotal role of PHA-P in red kidney bean allergy. Further, LC-MS/MS study revealed two IgE binding components of PHA-P as PHA-L and PHA-E. Enhanced specific IgE/IgG1 and β-hexosaminidase level elucidated the possible role of PHA-L and PHA-E in allergic manifestations. Furthermore, in the presence of IgE inhibitor piceatannol, reduced β-hexosaminidase release to some extent was noticed. The up regulated expression of GATA-3 and T-bet expression was observed in PHA-L as well as PHA-E groups. Taken together, this study revealed the fact that allergenicity potential of red kidney bean may get augmented due to the presence of different phytohemagglutinins. Although food allergy is an immune provocation induced mainly by dietary allergenic protein components of the food, the role of dietary lectins in the food induced allergic manifestations cannot be ruled out. Here we provide the systematic evidences about the allergenic potential of PHAs and further disclosed the culprit components as PHA-L and PHA-E. It is an important finding that the PHA-L and PHA-E can cause allergic manifestations via not only the IgE mediated pathway but also the non-IgE mediated allergic reactions as evident by the Th1/Th2 cytokines and transcription factors. Further, the PHA-L seems to be more allergenic than the PHA-E. This article is part of a Special Issue entitled: Translational plant proteomics.

Hypersensitivity to Ailanthus altissima (tree of heaven) pollen: identification of a major IgE-binding component

Ailanthusaltissima or Ailanthusglandulosa (Simaroubaceae) is known as tree of heaven. It is a dioecious plant with staminate and pistillate flowers that grow on separate trees. In recent years, A.altissima has been frequently planted in numerous areas, especially in arid and semiarid lands of Iran and also used as an ornamental tree in several Iran cities including Kerman. The aim of this research was to identify IgE-binding proteins responsible for type I hypersensitivities of A. altissima pollen extract. In this study, pollen’s proteins were extracted and analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Total protein content of pollen extracts was measured by Bradford assay. Allergenicity of pollen extract was evaluated by skin test and immunoblotting. Results showed that total protein concentration of A.altissima pollen was found to be 1.34 μg μl−1. In A. altissima pollen extract, different protein fractions were identified by SDS-PAGE mostly at 42, 53.7, 63, 87.7, 100 and 120 kDa. Skin tests showed a delayed hypersensitivity. Immunoblotting of A. altissima pollen extract with pooled subject’s sera detected a major IgE-binding component of 42 kDa. Moreover, these results will provide a platform for cloning cDNA encoding allergenic protein from A.altissima pollen.