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Summary: Background. Gibberellin Regulated Proteins (GRPs) are small glycoproteins that induce allergy to various types of fruit. This study aimed to evaluate co-sensitization to cypress pollen and other molecules responsible for fruit allergy, such as nsLTP (Pru p 3), PR-10 (Bet v1), and Profilin (Bet v2). Methods. Sixty subjects sensitized to peach GRP (Pru p 7) were consecutively recruited from four Italian centers: 28 males and 32 females (mean age 37.9 years; range 11-79). Specific IgE for Pru p 7, Pru p 3, Bet v 1, Bet v 2, cypress pollen extract (Cup s), and Cup a 1 were determined in all subjects. Results. Sensitization rates to Cup s, Cup a 1, Pru p 3, Bet v 1, and Bet v 2 in the entire studied population were 90.0%, 83.3%, 45.8%, 40.0%, and 30.0%, respectively. In subjects residing in Northern Italy, the respective sensitization rates were 96.4%, 80.0%, 50.0%, 73.3%, and 40.0%, while in those residing in Southern Italy, they were 83.3%, 86.7%, 40.0%, 6.7%, and 20.0%. The only significant difference was observed for PR-10 (p less than 0.0001) Co-sensitization to PR-10 was found to be associated with a reduced risk of anaphylaxis (OR: 0.125). Allergic reactions were most commonly triggered by peach (26/40), followed by orange (12/40), with other foods being less frequently implicated. Conclusions. This study confirms a high association between sensitization to Pru p 7 and cypress pollen and highlights a high percentage of co-sensitization to nsLTP, PR-10, and profilin. PR-10 emerged as a protective factor against anaphylaxis.

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Today, allergies have become a serious problem. PR-10 proteins are clinically relevant allergens that have the ability to bind hydrophobic ligands, which can significantly increase their allergenicity potential. It has been recently shown that not only the birch pollen allergen Bet v 1 but also the alder pollen allergen Aln g 1, might act as a true sensitizer of the immune system. The current investigation is aimed at the further study of the allergenic and structural features of Aln g 1. By using qPCR, we showed that Aln g 1 was able to upregulate alarmins in epithelial cells, playing an important role in sensitization. With the use of CD-spectroscopy and ELISA assays with the sera of allergic patients, we demonstrated that Aln g 1 did not completely restore its structure after thermal denaturation, which led to a decrease in its IgE-binding capacity. Using site-directed mutagenesis, we revealed that the replacement of two residues (Asp27 and Leu30) in the structure of Aln g 1 led to a decrease in its ability to bind to both IgE from sera of allergic patients and lipid ligands. The obtained data open a prospect for the development of hypoallergenic variants of the major alder allergen Aln g 1 for allergen-specific immunotherapy.

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The hazel allergen Cor a 1 is a PR-10 protein, closely related to the major birch pollen allergen Bet v 1. Hazel allergies are caused by cross-reactive IgE antibodies originally directed against Bet v 1. Despite the importance of PR-10 proteins in allergy development, their function and localization in the plant remain largely elusive. Therefore, the presence of Cor a 1 mRNA and proteins was investigated in different tissues, i.e., the female flower, immature and mature nuts, catkins, and pollen. Four yet unknown Cor a 1 isoallergens, i.e., Cor a 1.0501-1.0801, and one new Cor a 1.03 variant were discovered and characterized. Depending on the isoallergen, the occurrence and level of mRNA expression varied in different tissues, suggesting different functions. Interestingly, Cor a 1.04 previously thought to be only present in nuts, was also detected in catkins and pollen. The corresponding Cor a 1 genes were expressed in Escherichia coli. The purified proteins were analysed by CD and NMR spectroscopy. Immunoblots and ELISAs to determine their allergenic potential showed that the new proteins reacted positively with sera from patients allergic to birch, hazel and elder pollen and were recognized as novel isoallergens/variants by the WHO/IUIS Allergen Nomenclature Sub-Committee.

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INTRODUCTION: Hazelnuts are a leading trigger of food allergy. To date, several molecular components of hazelnut are available for component-resolved diagnosis. However, little is known about how simultaneous sensitization to multiple allergens affects the severity of the hazelnut-induced reaction. In a previous study, our group demonstrated a lower risk of systemic reactions to peach in patients sensitized to both Pru p 3 and Pru p 1 than in the patient monosensitized to peach LTP. We aimed to assess whether this was also true in hazelnut allergy in a cohort of adult patients. METHODS: Patients were selected based on a history of symptoms such as urticaria, vomiting, diarrhea, asthma, and anaphylaxis indicative of hazelnut IgE-mediated food allergy and graded according to a clinical severity scale. For all patients, specific IgE was determined for Cor a 1 and Cor a 8 and, for most patients, also Cor a 9. Patients were offered an oral food challenge in open format (OFC) with a cocoa-based roasted hazelnut spread on a voluntary basis in order to prescribe an appropriate diet. RESULTS: A total of two hundred and fourteen patients were recruited. Among these, 43 patients were monosensitized to Cor a 8. One hundred and seventy-one patients were sensitized to Cor a 1 (79.9%), and, among them, 48/171 (28.1%) were also Cor a 8 positive. Cor a 9 was evaluated in 124/214 patients, testing positive in 21/124 (16.9%). Patients monosensitized to Cor a 8 experienced systemic reactions more frequently than those sensitized to Cor a 1 ± Cor a 8 (p < 0.00001), with significantly more severe reactions (p < 0.0005) and testing more frequently positive at OFC (p < 0.0001). Regarding Cor a 9, the sensitized patients were significantly younger (p = 0.0013) and showed reactions of similar severity to patients who tested Cor a 9 negative, and these reactions were milder than in patients monosensitized only to Cor a 8. DISCUSSION/CONCLUSION: Sensitization to Cor a 1 seems to protect from the development of the severe systemic reactions induced by Cor a 8 sensitization, Cor a 9 does not influence the severity of symptoms in adult patients. The OFC with roasted hazelnut may help in dietary guidance.

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Allergies related to kiwi consumption have become a growing health concern, with their prevalence on the rise. Many of these allergic reactions are attributed to cross-reactivity, particularly with the major allergen found in birch pollen. This cross-reactivity is associated with proteins belonging to the pathogenesis-related class 10 (PR-10) protein family. In our study, we determined the three-dimensional structures of the two PR-10 proteins in gold and green kiwi fruits, Act c 8 and Act d 8, using nuclear magnetic resonance (NMR) spectroscopy. The structures of both kiwi proteins closely resemble the major birch pollen allergen, Bet v 1, providing a molecular explanation for the observed immunological cross-reactivity between kiwi and birch pollen. Compared to Act d 11, however, a kiwi allergen that shares the same architecture as PR-10 proteins, structural differences are apparent. Moreover, despite both Act c 8 and Act d 8 containing multiple cysteine residues, no disulfide bridges are present within their structures. Instead, all the cysteines are accessible on the protein's surface and exposed to the surrounding solvent, where they are available for reactions with components of the natural food matrix. This structural characteristic sets Act c 8 and Act d 8 apart from other kiwi proteins with a high cysteine content. Furthermore, we demonstrate that pyrogallol, the most abundant phenolic compound found in kiwi, binds into the internal cavities of these two proteins, albeit with low affinity. Our research offers a foundation for further studies aimed at understanding allergic reactions associated with this fruit and exploring how interactions with the natural food matrix might be employed to enhance food safety.

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Summary: Background. LTP allergy is often a challenge for clinicians. We evaluated a multiplex diagnostic approach with diverse cofactors to stratify LTP syndrome risk. Methods. Of the 1,831 participants screened with 'Allergy Explorer-ALEX-2', 426 had reactions to at least one LTP. Data was gathered and recorded via an electronic database. Results. Reactivity to peach Pru p 3 was found in 77% of individuals with LTP allergy. Higher levels of specific IgE and concurrent sensitization to more than 5 molecules (50% of all LTP-sensitised participants, 62% of symptomatic cases) were significantly associated with an increased risk of severe reactions (p = 0.001). Several cofactors, either alone or in combination, also influenced patients' clinical outcomes. Some cofactors increased the risk of severe reactions, such as mono reactivity to LTP in 44.6% of cases (p = 0.001), FDEIA in 10.8% of patients (p = 0.001), and FDNIH in 11.5% (p = 0.005). On the other hand, reactivity to PR10 (24.2%; p = 0.001), profilin hypersensitivity (10.3%; p = 0.001), and/or atopic dermatitis (16.7%; p = 0.001) had a mitigating effect on symptom severity. Conclusions. Clinical severity of LTP syndrome is associated with an expanded IgE repertoire in terms of the number of LTP components recognized and increased IgE levels in individual molecules. Ara h 9, Cor a 8, and Mal d 3 showed the strongest association with clinical severity. In addition, several cofactors may either exacerbate (FDEIA, FDHIH, and LTP monoreactivity) or ameliorate (atopic dermatitis and co-sensitization to profilin and/or PR10) individual patient outcomes. These factors may be utilized for the daily clinical management of LTP syndrome.

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The term allergy was coined in 1906 by the Austrian scientist and pediatrician Clemens Freiherr von Pirquet. In 1976, Dietrich Kraft became the head of the Allergy and Immunology Research Group at the Department of General and Experimental Pathology of the University of Vienna. In 1983, Kraft proposed to replace natural extracts used in allergy diagnostic tests and vaccines with recombinant allergen molecules and persuaded Michael Breitenbach to contribute his expertise in molecular cloning as one of the mentors of this project. Thus, the foundation for the Vienna School of Molecular Allergology was laid. With the recruitment of Heimo Breiteneder as a young molecular biology researcher, the work began in earnest, resulting in the publication of the cloning of the first plant allergen Bet v 1 in 1989. Bet v 1 has become the subject of a very large number of basic scientific as well as clinical studies. Bet v 1 is also the founding member of the large Bet v 1-like superfamily of proteins with members-based on the ancient conserved Bet v 1 fold-being present in all three domains of life, i.e., archaea, bacteria and eukaryotes. This suggests that the Bet v 1 fold most likely already existed in the last universal common ancestor. The biological function of this protein was probably related to lipid binding. However, during evolution, a functional diversity within the Bet v 1-like superfamily was established. The superfamily comprises 25 families, one of which is the Bet v 1 family, which in turn is composed of 11 subfamilies. One of these, the PR-10-like subfamily of proteins, contains almost all of the Bet v 1 homologous allergens from pollen and plant foods. Structural and functional comparisons of Bet v 1 and its non-allergenic homologs of the superfamily will pave the way for a deeper understanding of the allergic sensitization process.

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PURPOSE OF REVIEW: A significant fraction of allergens bind small molecular ligands, and many of these compounds are classified as lipids. However, in most cases, we do not know the role that is played by the ligands in the allergic sensitization or allergic effector phases. RECENT FINDINGS: More effort is dedicated toward identification of allergens' ligands. This resulted in identification of some lipidic compounds that can play active immunomodulatory roles or impact allergens' molecular and allergic properties. Four allergen families (lipocalins, NPC2, nsLTP, and PR-10) are among the best characterized in terms of their ligand-binding properties. Allergens from these four families are able to bind many chemically diverse molecules. These molecules can directly interact with human immune system and/or affect conformation and stability of allergens. While there is more data on the allergens and their small molecular ligands, we are just starting to understand their role in allergy.

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Induced systemic resistance (ISR) is a mechanism involved in the plant defense response against pathogens. Certain members of the Bacillus genus are able to promote the ISR by maintaining a healthy photosynthetic apparatus, which prepares the plant for future stress situations. The goal of the present study was to analyze the effect of the inoculation of Bacillus on the expression of genes involved in plant responses to pathogens, as a part of the ISR, during the interaction of Capsicum chinense infected with PepGMV. The effects of the inoculation of the Bacillus strains in pepper plants infected with PepGMV were evaluated by observing the accumulation of viral DNA and the visible symptoms of pepper plants during a time-course experiment in greenhouse and in in vitro experiments. The relative expression of the defense genes CcNPR1, CcPR10, and CcCOI1 were also evaluated. The results showed that the plants inoculated with Bacillus subtilis K47, Bacillus cereus K46, and Bacillus sp. M9 had a reduction in the PepGMV viral titer, and the symptoms in these plants were less severe compared to the plants infected with PepGMV and non-inoculated with Bacillus. Additionally, an increase in the transcript levels of CcNPR1, CcPR10, and CcCOI1 was observed in plants inoculated with Bacillus strains. Our results suggest that the inoculation of Bacillus strains interferes with the viral replication, through the increase in the transcription of pathogenesis-related genes, which is reflected in a lowered plant symptomatology and an improved yield in the greenhouse, regardless of PepGMV infection status.

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Raw strawberries contain allergens that cause oral allergic syndrome. Fra a 1 is one of the major allergens in strawberries and might decrease their allergenicity by heating, likely due to structural changes in the allergen leading to decreased recognition of the allergens in the oral cavity. In the present study, to understand the relationship between allergen structure and allergenicity, the expression and purification of 15N-labeled Fra a 1 were examined and the sample was used for NMR analysis. Two isoforms, Fra a 1.01 and Fra a 1.02, were used and expressed in E. coli BL21(DE3) in M9 minimal medium. Fra a 1.02 was purified as a single protein by using the GST tag approach, whereas histidine × 6-tag (his6-tag) Fra a 1.02 was obtained both as the full-length (∼20 kDa) and a truncated (∼18 kDa) form. On the other hand, his6-tag Fra a 1.01 was purified as a homogeneous protein. 15N-labeled HSQC NMR spectra suggested that Fra a 1.02 was thermally denatured at lower temperatures than Fra a 1.01, despite the high amino acid sequence homology (79.4%) of these isoforms. Furthermore, the samples in the present study allowed us to analyze ligand binding that probably affects structural stability. In conclusion, GST tag was effective for obtaining a homogeneous protein when his6-tag failed to give a single form, and the present study provided a sample that could be used for NMR studies of the details of the allergenicity and structure of Fra a 1.

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BACKGROUND: White root rot disease in rubber trees, caused by the pathogenic fungi Rigidoporus microporus, is currently considered a major problem in rubber tree plantations worldwide. Only a few reports have mentioned the response of rubber trees occurring at the non-infection sites, which is crucial for the disease understanding and protecting the yield losses. RESULTS: Through a comparative proteomic study using the two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) technique, the present study reveals some distal-responsive proteins in rubber tree leaves during the plant-fungal pathogen interaction. From a total of 12 selected differentially expressed protein spots, several defense-related proteins such as molecular chaperones and ROS-detoxifying enzymes were identified. The expression of 6 candidate proteins was investigated at the transcript level by Reverse Transcription Quantitative PCR (RT-qPCR). In silico, a highly-expressed uncharacterized protein LOC110648447 found in rubber trees was predicted to be a protein in the pathogenesis-related protein 10 (PR-10) class. In silico promoter analysis and structural-related characterization of this novel PR-10 protein suggest that it plays a potential role in defending rubber trees against R. microporus infection. The promoter contains WRKY-, MYB-, and other defense-related cis-acting elements. The structural model of the novel PR-10 protein predicted by I-TASSER showed a topology of the Bet v 1 protein family, including a conserved active site and a ligand-binding hydrophobic cavity. CONCLUSIONS: A novel protein in the PR-10 group increased sharply in rubber tree leaves during interaction with the white root rot pathogen, potentially contributing to host defense. The results of this study provide information useful for white root rot disease management of rubber trees in the future.

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The pollen-food allergy syndrome, also known as oral allergy syndrome, is characterized by local reactions in the mouth and throat after consuming certain raw plant foods in individuals sensitized to pollen from grass, weeds, and trees. Birch-apple is the prototype of this syndrome, with apple, pear, and plum being the most commonly associated foods. Symptoms are usually limited to the oral cavity but can include systemic reactions, including anaphylaxis. Sensitization to pollen allergens, such as lipid transfer proteins, profilin, and PR-10 proteins, triggers this syndrome. Its prevalence varies by geographic region and the predominant pollen type, affecting between 30% and 60% of food allergies. Diagnosis involves a clinical history, skin tests, and, in ambiguous cases, double-blind, placebo-controlled oral food challenges. Treatment primarily involves avoiding trigger foods.

El síndrome de alergia a alimentos y pólenes, también conocido como síndrome polen-alimento o síndrome de alergia oral, se caracteriza por una reacción local en la boca y faringe después de ingerir ciertos alimentos vegetales crudos, en individuos sensibilizados al polen de hierbas, malezas y árboles. El abedul-manzana es el prototipo de este síndrome, siendo la manzana, pera y ciruela los alimentos más comúnmente asociados. Los síntomas suelen limitarse a la cavidad oral, pero pueden incluir reacciones sistémicas, incluida la anafilaxia. La sensibilización a alérgenos de polen, como las proteínas de transferencia de lípidos, profilina y proteínas PR-10, desencadena este síndrome. Su prevalencia varía según la región geográfica y el tipo de polen predominante, afectando entre el 30% y el 60% de las alergias alimentarias. El diagnóstico implica historia clínica, pruebas cutáneas y, en casos ambiguos, pruebas de provocación alimentaria oral. El tratamiento consiste principalmente en evitar los alimentos desencadenantes.

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Bean anthracnose caused by the hemibiotrophic fungus Colletotrichum lindemuthianum is one of the most important diseases of common bean (Phaseolus vulgaris) in the world. In the present study, the whole transcriptome of common bean infected with C. lindemuthianum during compatible and incompatible interactions was characterized at 48 and 72 hpi, corresponding to the biotrophy phase of the infection cycle. Our results highlight the prominent role of pathogenesis-related (PR) genes from the PR10/Bet vI family as well as a complex interplay of different plant hormone pathways including Ethylene, Salicylic acid (SA) and Jasmonic acid pathways. Gene Ontology enrichment analysis reveals that infected common bean seedlings responded by down-regulation of photosynthesis, ubiquitination-mediated proteolysis and cell wall modifications. In infected common bean, SA biosynthesis seems to be based on the PAL pathway instead of the ICS pathway, contrarily to what is described in Arabidopsis. Interestingly, ~30 NLR were up-regulated in both contexts. Overall, our results suggest that the difference between the compatible and incompatible reaction is more a question of timing and strength, than a massive difference in differentially expressed genes between these two contexts. Finally, we used RT-qPCR to validate the expression patterns of several genes, and the results showed an excellent agreement with deep sequencing.

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There are two major clinically described forms of IgE-dependent soy allergy: (i) a primary dietary form, linked to sensitization against soy storage proteins Gly m 5 and Glym 6, and (ii) a form included in birch-soy syndromes linked to Gly m 4, a PR-10-like allergen. This second form sometimes causes severe systemic reactions, even anaphylaxis, especially on consuming certain forms of soy such as soymilks or smoothies. Skin prick tests and specific IgE assays against soy whole extracts lack sensitivity. Assays of anti-Gly m 4, Gly m 5 and Gly m 6 specific IgEs have been developed to overcome this obstacle, but they unfortunately lack specificity, especially for anti-Gly m 4. We hypothesized that the basophil activation test (BAT) using molecular soy allergens Gly m 4, Gly m 5 and Gly m 6 would both remedy the lack of sensitivity of other tests and offer, through its mechanistic contribution, greater specificity than the assay of anti-Gly m 4 specific IgEs. This would enable the two types of soy allergy to be separately identified. In a characteristic clinical example of PR-10-induced anaphylactic reaction after consuming soymilk, we report preliminary results of Gly m 4-exclusive positivity of BAT supporting our hypothesis. It will be necessary to confirm these results on more patients in subsequent studies, and to specify the place of the BAT in an overall diagnostic strategy. Meanwhile, soy BAT using molecular allergens is a promising diagnostic tool for soy allergy and probably also for follow-up in specific immunotherapies.

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The apple fruit (Malus domestica L. Borkh) is one of the most popular fruits worldwide. Beyond their beneficial properties, apples contain proteins that trigger allergic reactions in susceptible consumers. Mal d1 to d4 are allergens present in a variety of different isoforms in apples. In this study, we used proteomics to quantify all four Mal d proteins in 52 apple genotypes with varying allergenic potentials. A total of 195, 17, 14, and 18 peptides were found to be related to Mal d1, d2, d3, and d4 proteins, respectively of which 25 different Mal d proteins could be unambiguously identified. The allergenic potential of the Mal d isoforms was characterized by comparing the isoform abundance with the allergenic score of genotypes from oral challenge tests. The detected Mal d peptides presumably have different IgE binding properties and could be used as potential molecular markers to discriminate between hypoallergenic and hyperallergenic cultivars.

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Tomato spotted wilt virus impacts negatively on a wide range of economically important plants, especially tomatoes. When plants facing any pathogen attack or infection, increase the transcription level of plant genes that are produced pathogenesis-related (PR) proteins. The aim of this study is a genome-wide identification of PR-10 superfamily and comparative analysis of PR-10 and Sw-5b gene functions against tomato responses to biotic stress (TSWV) to systemic resistance in tomato. Forty-five candidate genes were identified, with a length of 64-210 amino acid residues and a molecular weight of 7.6-24.4 kDa. The PR-10 gene was found on ten of the twelve chromosomes, and it was determined through a genetic ontology that they were involved in six biological processes and molecular activities, and nine cellular components. Analysis of the transcription level of PR-10 family members showed that the PR-10 gene (Solyc09g090980) has high expression levels in some parts of the tomato plant. PR-10 and Sw-5b gene transcription and activity in tomato leaves were strongly induced by TSWV infection, whereas H8 plants having the highest significantly upregulated expression of PR-10 and Sw-5b gene after the inoculation of TSWV, and TSWV inoculated in M82 plants showed significantly upregulated expression of PR-10 gene comparatively lower than H8 plants. There was no significant expression of Sw-5b gene of TSWV inoculated in M82 plants and then showed highly significant correlations between PR-10 and Sw-5b genes at different time points in H8 plants showed significant correlations compared to M82 plants after the inoculation of TSWV; a heat map showed that these two genes may also participate in regulating the defense response after the inoculation of TSWV in tomato.

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Pollen-food syndrome (PFS) is characterized by allergic sensitization to proteins of pollens of grasses, weeds, and trees, which produce a type I hypersensitivity reaction that is associated with the intake of plant-derived foods that are usually in raw form. The most frequently-associated protein families are: profilins, PR-10, and ns LTP; however, others such as thaumatins, isoflavones, reductases, and B1,2 glucanases have been documented. The prototype syndrome is birch-fruit-vegetables, and of these, the most common is birch-apple due to the fact that more than 70 % of patients who are sensitized to birch present symptoms associated with the intake of plant-derived foods. The symptoms are restricted to the oral cavity; however, some patients may present systemic symptoms, including anaphylaxis, so it is important to identify the type of protein that is involved since the type of reaction that the patient may present depends on that. In spite of everything, it is considered an entity that may be under diagnosed due to its complex diagnosis and treatment, since the procedure, in most cases, is an elimination diet, because treatment with immunotherapy is not yet available. The purpose of this review is to describe the pathophysiology, as well as the most common pollen-food syndromes.

El síndrome polen-alimento (SPA) se caracteriza por la sensibilización alérgica a proteínas de pólenes de pastos, malezas y árboles, que producen una reacción de hipersensibilidad de tipo I, asociada a la ingesta de alimentos derivados de plantas, usualmente en forma cruda. Las familias de proteínas que más frecuentemente están asociadas son las profilinas, las PR-10 y las ns LTP; sin embargo, se ha documentado otras, como las taumatinas, isoflavonas reductasas y las B1,2 gluconasas. El síndrome prototipo es el abedul-frutas-vegetales, y de ellos el más común es el abedul-manzana, debido a que más de 70 % de los pacientes sensibilizados al abedul presentan síntomas asociados a la ingesta de alimentos derivados de plantas. Los síntomas están restringidos a la cavidad oral; sin embargo, algunos pacientes pueden presentar síntomas sistémicos, incluso anafilaxia, por lo que es importante identificar el tipo de proteína implicada, ya que de eso depende el tipo de reacción que puede presentar el paciente. Pese a todo, se considera una entidad que puede estar subdiagnosticada debido a su valoración y tratamiento complejos, debido a que el procedimiento en la mayor parte de los casos es dieta de eliminación, ya que aún no está disponible el tratamiento con inmunoterapia. El objetivo de esta revisión es describir la fisiopatología, así como los síndromes polen-alimento más comunes.

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To successfully colonize the plants, the pathogenic microbes secrete a mass of effector proteins which manipulate host immunity. Apple valsa canker is a destructive disease caused by the weakly parasitic fungus Valsa mali. A previous study indicated that the V. mali effector protein 1 (VmEP1) is an essential virulence factor. However, the pathogenic mechanism of VmEP1 in V. mali remains poorly understood. In this study, we found that the apple (Malus domestica) pathogenesis-related 10 proteins (MdPR10) are the virulence target of VmEP1 using a yeast two-hybrid screening. By bimolecular fluorescence (BiFC) and coimmunoprecipitation (Co-IP), we confirmed that the VmEP1 interacts with MdPR10 in vivo. Silencing of MdPR10 notably enhanced the V. mali infection, and overexpression of MdPR10 markedly reduced its infection, which corroborates its positive role in plant immunity against V. mali. Furthermore, we showed that the co-expression of VmEP1 with MdPR10 compromised the MdPR10-mediated resistance to V. mali. Taken together, our results revealed a mechanism by which a V. mali effector protein suppresses the host immune responses by interfering with the MdPR10-mediated resistance to V. mali during the infection.

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BACKGROUND: Peanut and soybean allergies are listed as contraindication in the package leaflet of isotretinoin, a widely used treatment of acne vulgaris. Cross-reactivity between PR10-proteins in peanut, tree nuts, and soybean is particularly common in patients with birch pollinosis and may lead to anaphylactic reactions in sensitized patients after intake of soybean oil containing isotretinoin capsules. CASE PRESENTATION: Here, we describe a young man with hazelnut and birch pollen allergy, who experienced exercise-induced anaphylaxis after isotretinoin intake on the third day of treatment. A complete allergy work-up was carried out, and sensitization to both peanut and soybean PR10-proteins was confirmed. However, oral provocation with isotretinoin remained negative in the absence of intense physical activity and longterm treatment was well tolerated. CONCLUSION: To our knowledge, this is the first report of an exercise-induced anaphylaxis due to isotretinoin therapy. Our literature review to assess tolerability of isotretinoin in patients allergic to peanut, tree nuts or soybean revealed only one other case of anaphylaxis in a cashew-nut allergic patient sensitized to soybean PR10-protein Gly m 4. While there are no reports on soybean allergic patients treated with isotretinoin, the vast majority of peanut or tree nut allergic patients tolerated isotretinoin. Therefore, we conclude that sensitization to soybean, peanut or tree nuts should not preclude isotretinoin therapy. Particular caution is however warranted in patients with soybean sensitization. Pre-treatment oral challenges with isotretinoin may be recommended and physicians should be aware of the potential role of cofactors.

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Kiwifruits have become one of the most common food sources triggering allergic reactions. In patients suffering from birch pollen related food allergy, reactions result from initial sensitization to the birch (Betula verrucosa) pollen allergen Bet v 1, followed by immunological cross-reactivity to structurally homologous proteins in kiwifruit. Clinical symptoms range from scratching and itching of the oral cavity to more severe immunological reactions such as rhino conjunctivitis. In this work we assigned backbone and side chain 1H, 13C and 15N chemical shifts of the 17 kDa PR-10 allergens Act c 8.0101 and Act d 8.0101 from golden (Actinidia chinesis) and green (Actinidia deliciosa) kiwifruit by solution NMR spectroscopy. The chemical shift data confirm the characteristic Bet v 1 fold for both proteins, consisting of a seven-stranded antiparallel ß-sheet interrupted by two short α-helices, along with a long C-terminal α-helix. Our data provide the basis for determining the three-dimensional solution structures of these proteins and characterizing their immunological cross-reactivity on a structural basis.

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