HLA variants and their association with IgE-Mediated banana allergy: A cross-sectional study.

Background: Banana allergy is on the rise in tropical regions. Advances in genomics and candidate gene identification have increased interest in genetic factors in food allergies. However, the genetic basis of IgE-mediated banana allergy is underexplored. Objective: To characterize HLA variants and their association with IgE-mediated banana allergy. Methods: This cross-sectional study recruited banana-allergic adults, confirmed by allergology tests, with non-allergic individuals as controls. Genomic DNA extraction and sequencing BAM files for HLA typing were conducted. Allele frequency was calculated using the direct counting method, and odds ratio (OR) with 95 % confidence interval (CI) were determined. Fisher's exact or chi-square tests were used to assess associations with Bonferroni's correction for multiple tests. The allele frequency of the Thai population from The Allele Frequency Net Database was used to compute the allele enrichment ratio (ER). Results: A total of 59 cases and 64 controls were recruited. HLA genotyping indicated potential associations of HLA-B*15:25 (OR 11.872; p-value 0.027), HLA-C*04:03 (OR 7.636; p-value 0.033), and HLA-DQB1*06:09 (OR 11.558; p-value 0.039) with banana allergy. However, after Bonferroni correction, none of these associations reached statistical significance. Comparing allele frequency with the general population from The Allele Frequency Net Database, our ER analysis revealed a higher prevalence in the banana allergy group for B*15:25 (ER 1.849), C*04:03 (ER 1.332), and DQB1*06:09 (ER 6.602) alleles. Conclusions: This study provides initial genetic insights into banana allergy, suggesting potential links with specific HLA alleles. Despite 12 initially identifying alleles, none were statistically significant after multiple testing correction. Larger studies are needed to detect possible significant correlations.

[TWO SCHOOL-AGED CASES OF FRUIT GIBBERELLIN-REGULATED PROTEIN ALLERGY WHICH NEED INDIVIDUAL REMOVAL STRATEGY IN SCHOOL LUNCH].

Gibberellin-regulated protein (GRP) is a newly discovered allergen in systemic fruit allergies. The kind of fruits which cause allergy is extensive as GRP is universally included in plants. Two children with GRP allergy were reported. Case 1: A 6-year-old boy experienced anaphylaxis while running after school lunch, which included canned peaches. A skin prick test (SPT) and blood examination suggested that he had peach GRP allergy. Six months and three years later, he experienced a similar episode after eating apple and citrus flesh, respectively. Case 2: An 11-year-old boy experienced anaphylaxis while running after consuming canned peaches during school lunch. A SPT implied that he had peach GRP allergy. However, a similar episode occurred after eating strawberry flesh 18 months later.Patients with GRP allergy often have one or more allergies to fruits other than peaches, as in these cases, and relevant fruits differ depending on the case. Particularly, clinicians should recognize that apple and citrus fruits are frequently included in school lunches as fruit flesh and as flavoring or seasoning in ready-made sauces or dressings. Therefore, an appropriate removal strategy should be considered in school lunches depending on each case of GRP allergy.

Revisiting Fruit Allergy: Prevalence across the Globe, Diagnosis, and Current Management.

Fruit allergies manifest with a diverse array of clinical presentations, ranging from localized contact allergies and oral allergy syndrome to the potential for severe systemic reactions including anaphylaxis. The scope of population-level prevalence studies remains limited, largely derived from single-center or hospital-based investigations. In this comprehensive review, we conducted a systematic literature search spanning the years 2009 to 2023, with full acknowledgment of potential analytical biases, to provide a global overview of fruit allergy prevalence. The primary mechanistic underpinning of fruit allergies stems from cross-reactivity between aeroallergens and food allergens, a consequence of structurally similar epitopes-a phenomenon recognized as pollen food allergy syndrome (PFAS). In the era of molecular allergology, numerous studies have dissected allergen components with substantial clinical relevance. Within this review, we explore important allergenic molecules found in plant-based foods, scrutinize pertinent cross-reactivity patterns, and offer insights into management recommendations. Additionally, we compare guideline recommendations to enhance clinical understanding and inform decision making.

Prevalence, clinical presentation, and associated atopic diseases of pediatric fruit and vegetable allergy: A population-based study.

BACKGROUND: In children, fruit and vegetable allergies are often overlooked compared with well-known allergies such as those to eggs, milk, and shellfish. Therefore, this study aimed to analyze fruit and vegetable allergies in children, including prevalence, types of food allergens, clinical presentation, management, and associated comorbid atopic diseases. METHODS: In 2012, a nationwide, cross-sectional, random sampling questionnaire-based survey for common fruit and vegetable allergies was conducted in Taiwan. Information regarding these plant food allergies was collected. Physicians diagnosed food allergies according to the descriptions of convincing symptoms. Enrolled questionnaires were reviewed by expert pediatricians. RESULTS: A total of 9,982 valid questionnaires were analyzed. The overall prevalence of fruit and vegetable allergies was 5.6% (n = 560) and 3.0% (n = 304), respectively. The most common fruit allergen was mango, followed by kiwifruit, whereas taro and bamboo shoot were the most common vegetable allergens. Meanwhile, most allergic symptoms were of the mucocutaneous tissue, followed by the upper airway and gastrointestinal tract. Most only required avoidance of allergens and not medical treatment. Children with fruit or vegetable allergies had a higher percentage of comorbid atopic dermatitis, allergic rhinitis, and asthma than those without food allergies; additionally, the proportion of comorbid atopic diseases was similar between fruit and vegetable allergies and shellfish allergy. One child developed anaphylaxis due to a corn allergy. CONCLUSIONS: Fruits and vegetables are common food allergens in Taiwanese children who present with diverse and potentially severe symptoms. Children with plant food allergies had a percentage of comorbid atopic diseases similar to that of shellfish allergy, the most common allergen. These findings indicate the importance of considering fruit and vegetable allergies in children.

Determination of Severe Peach Allergens, Gibberellin-Regulated Protein, and Lipid Transfer Protein, Using Monoclonal Antibodies.

In this study, monoclonal antibodies against two major fruit allergens-gibberellin-regulated protein (GRP) and lipid transfer protein (LTP)-were established. Sandwich enzyme-linked immunosorbent assays (ELISAs) for the quantification of peach GRP and LTP were constructed using these antibodies. Both ELISAs reacted with the respective antigens when heated at 100ºC for 20 min, but not when reduced with sodium sulfite, indicating that GRP and LTP are heat-stable, while disulfide bonds play an important role in their native steric structures. GRP and LTP in peaches and peach-containing foods were quantified by these ELISAs. In both cases, there were few differences among peach cultivars normally available on the market; however, concentrations were higher when the peach was ripe. GRP was localized in the pulp of the peach, while LTP was present in the peel. They could be quantified in peach-containing beverages, as well as in dried and canned peaches. GRP in Japanese apricots could also be determined using this ELISA, as its amino acid sequence is the same as that of peach GRP. Then, high concentrations of GRP were detected in umeboshi, a traditional Japanese pickled apricot. Peach leaves were found to have a high LTP content, accordingly, LTP was also observed in lotions containing peach leaf extract. The ability to quantitatively detect GRP and LTP in this study will, therefore, contribute to the improvement of component-resolved diagnoses and quality of life in patients allergic to peaches.

Effect of pre-harvest and post-harvest conditions on the fruit allergenicity: A review.

Fruits are an important source of vitamins and antioxidants that can effectively delay aging and contribute to health and well-being of the human kind. However, they are growing to be one of the primary elicitors of food allergies around the world. Fruit allergens can induce an IgE-mediated (Immunoglobulin E) reaction, presenting with a symptom like localized oral allergy syndrome (OAS). Numerous studies showed that varying environmental and cultivation conditions can influence the fruit allergen content during flowering and ripening stages. Further, the variety, harvesting maturity, and storage conditions can also significantly influence the allergenicity potential. For example, unripe apples and tomatoes have lower levels of allergens compared to ripened fruits. Researchers have also reported that modified atmosphere packaging (MAP) can help reduce Mal d 3 content present in apples during storage. Post-harvest processing like peeling is also considered a good method to help reduce the overall allergenicity in few fruits whose peel might contain majority of the allergens. This review will discuss the overall influence of both pre-harvest and post-harvest factors on the fruit allergens. We will also discuss the progress regarding the cause, symptoms and diagnostic methods of fruit based allergies.

[SENSITIVITY OF FRUIT-SPECIFIC IgE SCREENING IN MULTI-PANEL ANTIBODY TESTING].

BACKGROUND: One of the strengths of multi-panel IgE testing is that it facilitates screening for IgE antibodies (Abs) in allergic patients by providing data on levels of IgE Abs to multiple allergens at the same time. Nonetheless, its diagnostic sensitivity for clinical use has not been well-studied. METHODS: We tested sera from 33 fruit-allergic patients. The sensitivity of determining IgE Abs to fruit allergens using the MAST Immunosystems (MAST) system and the View Allergy 39 (VA) system was calculated separately in patients sensitized to PR-10 or to profilin, and compared with that of single-panel IgE testing (ImmunoCAP system). RESULTS: In both the PR-10 sensitized and 31 profilin sensitized groups, the sensitivity of the IgE Abs to apple measured by VA (87%, and 83%, respectively) was almost identical to that of ImmunoCAP. On the other hand, the sensitivity of IgE Abs to peach measured by MAST (23% and 25%, respectively) was markedly lower than that of ImmunoCAP. CONCLUSIONS: The sensitivity of fruit IgE Abs in the MAST system was remarkably lower than that of the ImmunoCAP system. Caution is necessary in clinical practice when interpreting of the results of some multipanel IgE testing.

Evaluation of serum IgE in peach-allergic patients with systemic reaction by using recombinant Pru p 7 (gibberellin-regulated protein).

BACKGROUND: Lipid transfer protein (LTP) is a major fruit allergen. It has, however, recently been revealed that the systemic reaction in peach-allergic patients is related not only to LTP (Pru p 3) but also to gibberellin-regulated protein (Pru p 7). We investigated recombinant Pru p 7 (rPru p 7) for its potential use in worldwide standardization for the diagnosis of peach allergy. METHODS: Natural Pru p 7 (nPru p 7) was purified from peach crude extract using a monoclonal antibody affinity column. Complementary DNA for Pru p 7 was cloned and expressed in Escherichia coli and Pichia pastoris. Serum immunoglobulin (Ig) E in peach-allergic patients was examined by enzyme-linked immunosorbent assay (ELISA) using nPru p 7 and rPru p 7 (E. coli product: erPru p 7 and P. pastoris product: prPru p 7). RESULTS: Peach-allergic patients (n=27) were diagnosed and categorized into oral reaction (n=10) or systemic reaction (n=17). The nPru p 7 positivity based on serum IgE levels was 52% in the systemic-reaction group and 0% in the oral-reaction group (P<0.05). In the systemic-reaction group, there was no significant difference in reactivity between nPru p 7 and prPru p 7, but the reactivity of erPru p 7 was significantly lower than those of nPru p 7 and prPru p 7 (P<0.05). CONCLUSIONS: We found that prPru p 7 exhibited reactivity in ELISA comparable to that of nPru p 7 for the diagnosis of peach allergy with systemic reaction.

[ORAL AND SYSTEMIC SYMPTOMS IN CHILDREN WITH FRUIT ALLERGY].

BACKGROUND AND PURPOSE: The principal aim of this study was to clarify the clinical profile of pediatric patients with fruit allergies. SUBJECTS AND METHODS: We assigned 265 pediatric patients with fruit allergies who were receiving outpatient treatment at Aichi Children's Health and Medical Center and 32 who underwent kiwi or banana oral food chal- lenge (OFC) test to an oral symptom group or a systemic symptom group and retrospectively examined their clinical profiles and prognosis from their medical records. RESULTS: The most common cause of fruit allergy was kiwi (139 patients, 21% of all patients). Watermelon had the highest oral symptom induction rate (97%), whereas banana had the highest systemic reaction induction rate (46%). In the oral symptom group, the prevalence of hay fever was 54% and 66% of patients showed aller- gic reaction to multiple fruits. In contrast, in the systemic symptom group, the prevalence of pollen allergies was 24% and 77% of patients showed allergic reaction to a single fruit only. The results revealed that 65% of patients allergic to bananas had infant-onset allergy and seven among 20 patients were confirmed acquisition of tolerability by the OFC test. CONCLUSION: Our data suggest that there is a difference in the clinical profile and disease type between patients with oral symptoms and those with primarily systemic symptoms. It is important to differentiate between these patients for accurate diet guidance, safety management, and prognosis estimation.

An overview of fruit allergy and the causative allergens.

Plant allergens, being one of the most widespread allergenic substances, are hard to avoid. Hence, their identification and characterization are of prime importance for the diagnosis and treatment of food allergy. The reported allergies to fruits mainly evoke oral allergy syndrome caused by the presence of cross-reactive IgE to certain pollens and thus, allergy to fruits has also been linked to particular pollens. Many fruit allergies are being studied for their causative allergens, and are being characterized. Some tropical or exotic fruits are responsible for region-specific allergies for which only limited information is available, and generally lack allergen characterization. From a survey of the literature on fruit allergy, it is clear that some common fruits (apple, peach, musk melon, kiwi fruit, cherry, grape, strawberry, banana, custard apple, mango and pomegranate) and their allergens appear to be at the center of current research on food allergy. The present review focuses on common fruits reported as allergenic and their identified allergens; a brief description of allergens from six rare/tropical fruits is also covered.

Component-resolved diagnosis using microarray for diagnosing hypersensitivity to raw fruits in birch pollen sensitized children

PURPOSE: Recently, component-resolved diagnosis (CRD) using microarray technology has been introduced to the field of clinical allergy. This study was aimed to investigate the clinical usefulness of microarray-based IgE detection for diagnosing clinical raw fruit allergy in birch pollen-sensitized children. METHODS: Thirty-one children with allergic disease who had been sensitized to pollen were studied. A pollen-sensitized patient was defined as having an allergen-specific history with concomitant positive skin-prick tests (SPTs) to natural allergen extracts or positive allergen-specific IgE. All subjects underwent SPTs for pollen and fruit. In all subjects, specific IgE to pollen and fruit were measured by ImmunoCAP. Specific IgE antibodies to allergen components were determined by a customized allergen microarray (ISAC). RESULTS: Thirteen of the 31 patients (41.9%) had a history of fruit hypersensitivity with positive SPTs. Measuring IgE to allergen components by ISAC, all the 13 patients with fruit hypersensitivity were positive to at least one of Mal d 1, Pru p 1, Pru p 3, Act d 8, and Act d 2 compared to 12 of the 13 patients (92.3%) who had at least 1 positive IgE to fruits (apple, peach, and kiwi) using ImmunoCAP. The sensitivity of ISAC microarray was 100.0% for the diagnosis of fruit hypersensitivity, but its specificity was 27.7% (5/18). The sensitivity of ImmunoCAP was 92.3%, and its specificity was 83.3%. CONCLUSION: The sensitivity of allergen components tested using microarray for the diagnosis of clinical fruit hypersensitivity in children with pollen allergy was high; however, its specificity was low.

Prevalence of latex allergy in spina bifida patients in Singapore.

BACKGROUND: Latex allergy and its clinical presentation are rising in prevalence across the globe, especially amongst patients with spina bifida (SB). While studies have been well-established in Europe and America, data from Asia are limited. OBJECTIVE: The aim of this study is to investigate the scenario in Singapore. METHODS: 35 subjects with SB, aged 5 to 32 years answered a questionnaire and underwent skin prick test (SPT) using a latex solution, 3 common house dust mites and 3 commonly cross-reacting food allergens (banana, kiwi and avocado). We also noted the relation between latex sensitization with atopy and doctor-diagnosed allergy. The prevalence of cross-reactivity with fruits was also studied. RESULTS: Sensitization to latex (i.e. a positive SPT) was found in 16 (46%, 95% confidence interval 29%-63%) of the subjects. Only 5 (31%) of the subjects who were sensitized to latex had clinical manifestations. Atopy (i.e. positive SPT to house dust mites) was present in 23 (66%) of the subjects and 13 (57%) of them was also sensitized to latex. There was a positive trend between latex sensitization and atopy (81.2% vs. 52.6%, p = 0.076), as well as latex sensitization with those having both atopy and doctor-diagnosed allergy (i.e. asthma, allergic rhinitis, eczema, drug allergy) (93.8% vs. 63.2%, p = 0.032). Only 6 (38%) subjects had allergy to the food allergens tested. CONCLUSION: Almost half of the SB patients in Singapore are sensitized to latex. This number is comparable to that in Europe and America. Positive trend between latex sensitization and those with both atopy and doctor-diagnosed allergy (p = 0.032) is suggestive of a possible cause-effect relationship.

Molecular cloning, characterization, and expression of Cuc m 2, a major allergen in Cucumis melo.

BACKGROUND: Several studies reported the clinical features of IgE-mediated hypersensitivity after ingestion of melon. Melon allergy is a common IgE-mediated fruit allergy in Iran. This prompted us to investigate immunochemical and molecular properties of the major allergen in melon fruit, to compare the IgE-binding capacity of the natural protein with the recombinant allergen, and to determine cross-reactivity of the major allergen with closely-related allergens from other plants displaying clinical cross-reactivity with melon. METHODS: Identification and molecular characterization of the major melon allergen were performed using IgE immunoblotting, allergen-specific ELISA, affinity-based purifications, cross-inhibition assays, cloning, and expression of the allergen in Escherichia coli. RESULTS: Melon profilin was identified and isolated as a major IgE-binding component and designated as Cuc m 2. Sequencing corresponding cDNA revealed an open reading frame of 363 bp coding for 131 amino acid residues and two fragments of 171 bp and 383 bps for the 5'and 3' UTRs, respectively. Significant cross-reactivity was found between melon profilin and Cynodon dactylon, tomato, peach, and grape profilins in cross-inhibition assays. Although the highest degree of amino acid identity was revealed with watermelon profilin, there was no significant cross-reactivity between melon and watermelon profilins. CONCLUSION: Melon profilin is the major IgE-binding component in melon extract, and the recombinant and natural forms exhibited similar IgE-binding capacities. A part of the fruit-fruit and pollen-fruit cross-reactions could be explained by the presence of this conserved protein; however, sequence homology provides insufficient information to predict IgE cross-reactivity of profilins.

Prevalence of latex allergy in spina bifida patients in Singapore

BACKGROUND: Latex allergy and its clinical presentation are rising in prevalence across the globe, especially amongst patients with spina bifida (SB). While studies have been well-established in Europe and America, data from Asia are limited. OBJECTIVE: The aim of this study is to investigate the scenario in Singapore. METHODS: 35 subjects with SB, aged 5 to 32 years answered a questionnaire and underwent skin prick test (SPT) using a latex solution, 3 common house dust mites and 3 commonly cross-reacting food allergens (banana, kiwi and avocado). We also noted the relation between latex sensitization with atopy and doctor-diagnosed allergy. The prevalence of cross-reactivity with fruits was also studied. RESULTS: Sensitization to latex (i.e. a positive SPT) was found in 16 (46%, 95% confidence interval 29%-63%) of the subjects. Only 5 (31%) of the subjects who were sensitized to latex had clinical manifestations. Atopy (i.e. positive SPT to house dust mites) was present in 23 (66%) of the subjects and 13 (57%) of them was also sensitized to latex. There was a positive trend between latex sensitization and atopy (81.2% vs. 52.6%, p = 0.076), as well as latex sensitization with those having both atopy and doctor-diagnosed allergy (i.e. asthma, allergic rhinitis, eczema, drug allergy) (93.8% vs. 63.2%, p = 0.032). Only 6 (38%) subjects had allergy to the food allergens tested. CONCLUSION: Almost half of the SB patients in Singapore are sensitized to latex. This number is comparable to that in Europe and America. Positive trend between latex sensitization and those with both atopy and doctor-diagnosed allergy (p = 0.032) is suggestive of a possible cause-effect relationship.

Síndrome de alergia oral / Oral allergy syndrome

A síndrome de alergia oral (SAO) é uma condição caracterizada por sintomas alérgicos mediados por IgE, que se restringem à mucosa oral. Em situações em que as manifestações são decorrentes da ingestão de frutas e vegetais em indivíduos sensibilizados aos pólens, o termo mais específico é síndrome pólen-frutas (SPF). Uma vez que as porções proteicas dos alérgenos envolvidos são degradadas pelo calor e enzimas digestivas, os sintomas são imediatos, restringem-se geralmente à cavidade oral e a forma cozida ou processada dos mesmos alimentos costuma ser bem tolerada.