Minor Allergens Research Articles

Three patterns of sensitization to mugwort, timothy, birch and their major allergen components revealed by Latent class analysis

BackgroundMugwort, timothy, and birch are commonly spread pollen allergens across China. Although several studies have described the rates of sensitization to mugwort, timothy, and birch in China, most of them just on specific whole-allergen extracts but little was known about the co-sensitization characteristics of its allergen components. This study aimed to explore the patterns of sensitization to mugwort, timothy, birch, and their major allergen components. MethodSerum specific IgE (sIgE) levels of allergen components of mugwort, timothy, birch, and cross-reactive carbohydrate determinants (CCD) were detected in 160 patients whose serum showed positive results to at least one of mugwort, timothy, and birch allergens via EUROBlotMaster system. Skin prick testing was utilized to assess the allergic reaction of grass, weed, and tree allergens. Latent class analysis was used to identify underlying patterns of sensitization to a series of allergen components and their corresponding extracts. Results88.8% of patients with allergic rhinitis and/or asthma were positive for mugwort-sIgE, 30% for timothy-sIgE, and 32.5% for birch-sIgE. By using the LCA model, three sensitization patterns as “Mugwort, Art v 4, Bet v 2 and Phl p 12 co-sensitized”, “Timothy, mugwort, and CCD co-sensitized”, “Mugwort and Art v 1 co-sensitized” were revealed based on optimal statistical fit in this study. Compared with other clusters, participants in “Mugwort, Art v 4, Bet v 2 and Phl p 12 co-sensitized” pattern were associated with higher sensitization rates of common grass and tree pollens allergen. The spearman’s coefficient between CCD and timothy was larger than the corresponding values of CCD with mugwort or birch. ConclusionCCD and profilin, as minor allergens in pollens, were associated with other pollen sIgE false positives presumably due to cross-reactivity. Patients sensitized with profilin had a significantly higher risk of sensitization to other pollens.

Management of Double Sensitization to Vespids in Europe.

Wasp allergy with a diagnostic profile of double sensitizations to vespid venom is a frequent clinical problem in areas where different genera of wasps are present. Identification of the insect responsible for serious reactions poses a diagnostic challenge as the only effective treatment to date is immunotherapy based on the specific venom. In southern Europe, the double sensitization to Vespula and Polistes venoms is highly frequent. It has been shown that the major allergenic proteins (Phospholipase A1 and Antigen 5) share sequences across the different genera and species, which would be the cause of cross-reactivity. Additionally, the minor allergens (Dipeptidyl-peptidases, Vitellogenins) have been found to share partial sequence identity. Furthermore, venom contains other homologous proteins whose allergenic nature still remains to be clarified. The traditional diagnostic tools available are insufficient to discriminate between allergy to Vespula and Polistes in a high number of cases. IgE inhibition is the technique that best identifies the cross-reactivity. When a double sensitization has indeed been shown to exist or great uncertainty surrounds the primary sensitization, therapy with two venoms is advisable to guarantee the safety of the patient. In this case, a strategy involving alternate administration that combines effectiveness with efficiency is possible.

Mapping Sequential IgE-Binding Epitopes on Major and Minor Egg Allergens

Introduction: Molecular studies of hen’s egg allergens help define allergic phenotypes, with IgE to sequential (linear) epitopes on the ovomucoid (OVM) protein associated with a persistent disease. Epitope profiles of other egg allergens are largely unknown. The objective of this study was to construct an epitope library spanning across 7 allergens and further evaluate sequential epitope-specific (ses-)IgE and ses-IgG₄ among baked-egg reactive or tolerant children. Methods: A Bead-Based Epitope Assay was used to identify informative IgE epitopes from 15-mer overlapping peptides covering the entire OVM and ovalbumin (OVA) proteins in 38 egg allergic children. An amalgamation of 12 B-cell epitope prediction tools was developed using experimentally identified epitopes. This ensemble was used to predict epitopes from ovotransferrin, lysozyme, serum albumin, vitellogenin-II fragment, and vitellogenin-1 precursor. Ses-IgE and ses-IgG₄ repertoires of 135 egg allergic children (82 reactive to baked-egg, the remaining 52 tolerant), 46 atopic controls, and 11 healthy subjects were compared. Results: 183 peptides from OVM and OVA were screened and used to create an aggregate algorithm, improving predictions of 12 individual tools. A final library of 65 sequential epitopes from 7 proteins was constructed. Egg allergic children had higher ses-IgE and lower ses-IgG₄ to predominantly OVM epitopes than both atopic and healthy controls. Baked-egg reactive children had similar ses-IgG₄ but greater ses-IgE than tolerant group. A combination of OVA-sIgE with ses-IgEs to OVM-023 and OVA-028 was the best predictor of reactive phenotype. Conclusion: We have created a comprehensive epitope library and showed that ses-IgE is a potential biomarker of baked-egg reactivity.

Identification of major and minor chicken allergens in dogs.

Allergens targeted by serum-specific immunoglobulin E (sIgE) in dogs clinically allergic to chicken have not been reported. To characterise the allergens targeted by sIgE in dogs sensitised and allergic to chicken. Sera from three dogs not sensitised to chicken, from 10 chicken sensitised dogs and from 12 chicken allergic dogs. Enzyme-linked immunosorbent assay (ELISA) and immunoblotting with a commercial chicken extract were utilized. The bands identified on immunoblotting were sequenced by mass spectrometry for allergen characterization. Using ELISA, we detected chicken-sIgE above the positive threshold in zero of three (0%) nonsensitised dogs, five of five (100%) chicken-sensitised dogs (a selection criterion), and in seven of 12 (58%) chicken-allergic dogs. Immunoblotting performed with the same extract revealed IgE-bound protein bands in 100% of all chicken-sensitised and -allergic dogs, respectively. To identify the allergens, we excised the corresponding bands on the electrophoretic gel, and submitted them for sequencing by mass spectrometry. We conclusively identified seven major allergens (serum albumin, pyruvate kinase M, enolase 3, creatine kinase M, lactate dehydrogenase A, glyceraldehyde-3-phosphate dehydrogenase and triose-phosphate isomerase) and one minor allergen (troponin C), which are relevant to dogs. We identified herein seven major chicken allergens for dogs, several of which are known to be cross-reactive allergens for humans. Based on their degree of sequence identity, these allergens exhibit the theoretical potential to be cross-reactive between poultry and mammalian meats; six of these allergens already are known to be cross-reactive between chicken and fish species. Future studies should address the clinical relevance and cross-reactivity potential of these chicken allergens in dogs.

Sensitization Profiles of Timothy Grass Pollen in Northern China.

PurposeGrass pollen is an important cause of IgE-mediated allergy in countries worldwide, especially within Europe. However, there has been no research on grass pollen allergy in northern China. We aimed to determine the status of grass pollen allergy and the sensitization patterns to Phleum pratense (P. pratense) in northern China.Patients and MethodsPollen data were collected for three geographic areas (Beijing, Shenmu, Shizuishan) in northern China. The study enrolled 101 patients (62 men; age range, 1–64 years; median age, 10 years) who had allergic rhinoconjunctivitis and/or asthma during the grass pollen season and positive skin prick test results positive to P. pratense. Serum-specific IgE (sIgE) against Phl p 1, Phl p 2, Phl p 5, Phl p 6, Phl p 7, Phl p 12 was measured by ImmunoCAP.ResultsThe pollen season of P. pratense was from June to September in Beijing, May to September in Shenmu and July to August in Shizuishan. P. pratense pollen accounted for 2–3% of the annual pollen index of total pollen counts. Among 101 patients with positive skin prick test results to P. pratense, 72% had detectable sIgE to P. pratense. Phl p 12 was the most frequently recognized component (45%), followed by Phl p 1 (22%), Phl p 5 (14%), Phl p 6 (8%) and Phl p 7 (3%). No patients had sIgE to Phl p 2. Ten sensitization patterns to the six components were observed. High rate of sIgE to Phl p 12 was positively correlated with co-sensitization to weed or tree pollen.ConclusionConsidering the pollen concentration, P. pratense was a minor pollen allergen in northern China and its pollen season overlapped with that of weed pollen. IgE sensitization to P. pratense was likely to be induced by cross-reactivity between grass pollen allergy and weed/tree pollen allergy.

Serum Albumin as a Cross-Reactive Component in Furry Animals May Be Related to the Allergic Symptoms of Patients with Rhinitis.

BackgroundThe prevalence of allergies has increased significantly in the past decade. Further research on allergic diseases caused by furry animals is of great importance for the clinical prevention, diagnosis and treatment of allergies.ObjectiveTo identify the sensitization profile and clinical association of various furry animal crude extracts and components based on component resolved diagnosis (CRD).MethodsA total of 211 patients with allergic rhinitis with sensitivities to cats and/or dogs were recruited, and the specific immunoglobulin E (sIgE) against various furry animals (such as dog/cat extracts and their components, pigeon, parrot, duck, chicken, sheep, rat, mouse, goose, cow and horse extracts) were measured to analyze the sensitization profiles, cross-reactivity and clinical relevance with regards to allergies.ResultsA total of 91.67% of cat-sensitized patients were sensitive to Fel d 1, while only 16.03% of cat-sensitized patients responded to Fel d 2. Can f 1 and Can f 5 were the major components of dogs, and the positive rates were 23.53% and 16.18%, respectively. Twenty percent of patients were sensitized to 10 other furry animals, and the positive rate was between 0% and 19.12%. There was a significant correlation between components (Can f 1–5 and Fel d 2) and 5 furry animals (mouse, sheep, Horse, rat, cow), especially between serum albumin (SA) (Can f 3, Fel d 2) and furry animals. Most of the animal crude extracts and components sensitization rates in patients who were SA-positive were significantly higher than that of patients who were SA-negative. In particular, for sensitization to mice, sheep, horses, rats and cows, more than 10-fold higher in patients who were SA-positive than in patients who were SA-negative. The VAS of symptoms and life of quality (LoQ) in the SA-sensitized patients was higher than that in unsensitized patients, and the patients with lipocalin sensitivities had a worse LoQ.ConclusionSerum albumin Fel d 2 and Can f 3, as minor allergens in cats and dogs, but not lipocalin or prostatic kallikrein, is associated with other furry animals presumably due to serum albumin cross-reactivity. Patients sensitized with serum albumin had a significantly higher risk of sensitization to other animals and had a higher rhinitis VAS score.

Ефективність алергенспецифічної імунотерапії пилковими алергенами в дітей із позиції молекулярної алергології

Мета роботи — встановити можливі причини неефективності алергенспецифічної імунотерапії (АСІТ) пилковими алергенами (бур’янів) у дітей із сезонним алергічним ринітом і/або бронхіальною астмою на підставі вивчення гіперчутливості до алергенів, аналізу анамнестичних даних. Матеріали та методи. Проведено алерготестування 192 дітей. 52 пацієнтам проведене анамнестичне опитування з акцентом на перехресну алергію та супутню патологію верхніх дихальних шляхів, а також на ефективність АСІТ. Статистична обробка результатів проведена в програмі Statistica for Windows 6.0. Результати. Серед хворих на поліноз переважала гіперчутливість до амброзії (56 %), циклахени (46 %) та соняшника (58 %). До злакових рослин (райграс, грястиця, вівсяниця) чутливі 10—20 % пацієнтів. 23 % дітей мають сенсибілізацію до 5 та більше алергенів (в середньому до 3,3 ± 0,4). 52 % дітей мають супутню харчову алергію, 15 % — синдром оральної алергії, третина дітей — аденоїдні вегетації, гіпертрофію глоткових мигдалин, у 13 % алергічний риніт ускладнювався синуситом. Незадовільний клінічний ефект АСІТ пилковими алергенами асоціювався з наявністю поєднаної пилково-грибкової сенсибілізації, перехресної харчової та пилкової алергії, із сенсибілізацією до 4 та більше пилкових алергенів, з полівалентною алергією, а також спостерігався при поєднанні алергічного риніту із синуситом (р < 0,05). Висновки. Перед початком АСІТ дітям із полінозами необхідно визначити групу ризику стосовно можливої неефективності цього методу терапії та рекомендувати їм визначення специфічних імуноглобулінів класу Е до мажорних та мінорних алергенів для прогнозування ефективності АСІТ.

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Characterization of New Allergens from the Venom of the European Paper Wasp Polistes dominula.

Discriminating Polistes dominula and Vespula spp. venom allergy is of growing importance worldwide, as systemic reactions to either species’ sting can lead to severe outcomes. Administering the correct allergen-specific immunotherapy is therefore a prerequisite to ensure the safety and health of venom-allergic patients. Component-resolved diagnostics of Hymenoptera venom allergy might be improved by adding additional allergens to the diagnostic allergen panel. Therefore, three potential new allergens from P. dominula venom—immune responsive protein 30 (IRP30), vascular endothelial growth factor C (VEGF C) and phospholipase A2 (PLA2)—were cloned, recombinantly produced and biochemically characterized. Sera sIgE titers of Hymenoptera venom-allergic patients were measured in vitro to assess the allergenicity and potential cross-reactivity of the venom proteins. IRP30 and VEGF C were classified as minor allergens, as sensitization rates lay around 20–40%. About 50% of P. dominula venom-allergic patients had measurable sIgE titers directed against PLA2 from P. dominula venom. Interestingly, PLA2 was unable to activate basophils of allergic patients, questioning its role in the context of clinically relevant sensitization. Although the obtained results hint to a questionable benefit of the characterized P. dominula venom proteins for improved diagnosis of venom-allergic patients, they can contribute to a deeper understanding of the molecular mechanisms of Hymenoptera venoms and to the identification of factors that determine the allergenic potential of proteins.

Component-Resolved Diagnosis of American Cockroach (Periplaneta americana) Allergy in Patients From Different Geographical Areas

Background: Manifestation of respiratory allergy to American cockroach (Periplaneta americana) is prominent in the subtropical and tropical areas. However, co-existing perennial indoor inhalant allergies frequently compromise clinical diagnosis of cockroach allergy, and the analysis of sensitization pattern is limited by the lack of Periplaneta allergens widely available for component-resolved diagnostics (CRD).Objective: To evaluate a collection of previously described recombinant Periplaneta allergens for CRD in cockroach allergy.Methods: A panel of nine recombinant Periplaneta allergens (Per a 1–5, 7–10) was generated, purified, and subjected to physicochemical characterization by applying circular dichroism (CD) spectroscopy, dynamic light scattering (DLS), amino acid (AA) analysis, and mass spectrometry (MS). Patients (n = 117) from India, Korea, Venezuela, and Iran, reporting perennial respiratory indoor allergies with IgE sensitization to cockroach (P. americana and/or Blattella germanica), were included. The sensitization profile was monitored by the experimental ImmunoCAP testing.Results: ImmunoCAP testing confirmed IgE sensitization to Periplaneta and/or Blattella extract in 98 of 117 patients (r = 0.95). Five out of 117 patients were sensitized to only one of the two cockroach species. Within the whole study group, the prevalence of sensitization to individual allergens varied from 4% (Per a 2) to 50% (Per a 9), with the highest IgE values to Per a 9. Patients from four countries displayed different sensitization profiles at which Per a 3 and Per a 9 were identified as major allergens in India and Korea. Periplaneta-derived lipocalin and myosin light chain were characterized as new minor allergens, designated as Per a 4 and Per a 8. Periplaneta extract showed higher diagnostic sensitivity than all individual components combined, suggesting the existence of allergens yet to be discovered.Conclusion: Utilization of a panel of purified Periplaneta allergens revealed highly heterogeneous sensitization patterns and allowed the classification of lipocalin and myosin light chain from Periplaneta as new minor allergens.

Humanized Mediator Release Assay as a Read-Out for Allergen Potency.

Mediator release assays analyze in vitro immunoglobulin E (IgE)-mediated degranulation and secretion of mediators by effector cells, such as mast cells and basophils, upon stimulation with serial dilutions of putative allergens. Therefore, these assays represent an essential tool that mimics the in vivo degranulation process, which occurs upon allergen exposure in sensitized patients or in skin prick tests. Additionally, these assays are usually employed to investigate the allergenic potential of proteins and the reactivity of patients' sera's reactivity. Herein, we describe a simple 2-day protocol using an immortalized rat basophil leukemia cell line transfected and humanized with the human high-affinity IgE plasma-membrane receptor (FcεRI). This variant of the mediator release assay is a robust, sensitive, and reproducible in vitro cell-based system without the need to immobilize the antigen to solid matrices. The protocol consists of the following steps: (1) complement inactivation of human sera, (2) harvesting, seeding, and passive sensitization of the cells, (3) stimulation with antigen to cause mediator release, and (4) measuring of β-hexosaminidase activity as a surrogate for the released inflammatory mediators, such as histamine. The assay represents a useful tool to assess the capacity of the allergen-IgE cross-linking to trigger cell degranulation and can be implemented to standardize allergen extracts, to compare patients' reactivity to minor or major allergens and to allergenic extracts (pollen, cat dander, etc.), to investigate the potency of allergen homologs, isoforms, and fold-variants (e.g., hypoallergenicity), as well as the effects of ligands on the allergenic activity. A more recent application includes the use of the assay to monitor the treatment efficacy in the course of allergen immunotherapy.

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.

Crystal structure of timothy grass allergen Phl p 12.0101 reveals an unusual profilin dimer

Timothy grass pollen is a source of potent allergens. Among them, Phl p 1 and Phl p 5 are thought to be the most important, as a majority of timothy grass-allergic individuals have IgE antibodies directed against these two allergens. The profilin from timothy grass (Phl p 12) has been registered as a minor allergen, with up to 35% of individuals in populations of grass pollen allergic patients showing IgE binding to Phl p 12. Profilins are primarily minor allergens and are known for a high likelihood of co-sensitization as well as cross-reactivity situations caused by their sequence and structure similarity. The crystal structure of Phl p 12.0101 was determined and it revealed that this allergen may form an unusual dimer not previously observed among any profilins. For example, the Phl p 12 dimer has a completely different geometry and interface when compared with the latex profilin (Hev b 8) dimer that has its crystal structure determined. The structure of Phl p 12.0101 is described in the context of allergenic sensitization and allergy diagnostics. Moreover, the structure of the Phl p 12.0101 dimer is discussed, taking into account the production of recombinant allergens and their storage.

Are the Terms Major and Minor Allergens Useful for Precision Allergology?

Are the Terms Major and Minor Allergens Useful for Precision Allergology?

Separation from major allergens and co-purification of two minor allergens in peanut extract

Peanut allergies can cause anaphylaxis and even death, with the four major allergens (Ara h 1, 2, 3, and 6) being responsible for serious reactions in the US, while the minor allergens, Ara h 8 and 9, are either associated with minor symptoms of the oral cavity or are generally less recognized by allergic people outside of the Mediterranean, and occasionally cause systemic allergic reactions. A protocol to separate major and minor allergens in extracts for diagnostics like skin prick tests may therefore be desirable.

Rare food allergens.

In food allergy, only a restricted number of protein families have been identified to contain allergenic proteins. These can be further grouped into major allergens, responsible for inducing allergic reactions in the majority of patients allergic to the food source, as compared to minor allergens only affecting a small number of food allergic patients. In addition, rare allergens have only been described for single cases so far. Rare allergens can derive from novel foods, including exotic varieties and foods not yet frequently consumed in certain regions. Also, new or modified processing strategies could induce a higher allergenicity in certain dietary proteins. And finally, low abundancy and/or low allergenic activity may also account for some rare allergens. For allergenic risk assessment, cross-reactivity of novel allergens with already known allergens is in place and facilitates the identification of potential new allergens, while de novo sensitization to yet undefined allergens can only be described retrospectively. This review presents some examples of recently identified rare allergens.

Major and minor allergen Ige reactivity of purple mud crab (Scylla tranquebarica) against a cross-reactive allergen in crustacean and molluscs in patients with a seafood allergy

Background: Crabs have been reported as a high exporter of protein and contains great nutritional value. Objective: It is necessary to identify the allergens and the cross-reactivity concerning the mud crab Scylla tranquebarica, shellfish, and mollusks for control of food safety and to facilitate in the identification and treatment of symptoms related to allergy. Methods: IgE extracted of serum from five patients who suffered from anaphylaxis due to crab and five healthy patients. It was taken for analysis via immunoblotting against 11 different crustaceans and molluscs. Results: Based on the analysis, the sera from the patients had responded specifically to a 38-kDa protein in all the crustaceans and molluscs, and it is known as tropomyosin. In certain absorption studies, the 38-kDa protein had exhibited to be the immunodominant epitopes among all crustaceans and molluscs. Sera from all five subjects with Scylla tranquebarica allergy showed IgE reactivates against crabs, prawns, and molluscs, but not to the chicken or murine muscle. Conclusions: Therefore, it can be concluded that the allergic epitopes on tropomyosin are preserved not only in shellfish but also in insects. Thus, a further examination should be done onto the patient with shrimp allergy to determine the potential cross-reactivity inhalant or sensitivity to ingested insects.

Molecular allergy diagnosis using pollen marker allergens and pollen panallergens: Five patterns seen in multiple test reactions topollen extracts.

Polysensitizations to tree, grass, and weed pollen are found in ~ 20% of pollen-allergic individuals. They are often based on broad IgE cross-reactivities to pollen panallergens belonging to highly conserved protein families: 1. profilins, 2. polcalcins (calcium-binding proteins in pollen), 3. cyclophilins. They represent highly conserved cross-reactive minor allergens present in all pollen species, but also in plant foods and other organisms. Despite being rarely clinically relevant they can hamper allergy diagnostic tests with extracts. In this situation, molecular allergy diagnosis is able to distinguish broad cross-reactivity due to allergen-specific IgE to pollen panallergens (i.e. profilins Bet v 2 or Phl p 12; polcalcins Bet v 4 or Phl p 7; and, in the future, cyclophilins Bet v 7 or Ole e 15) from primary IgE sensitizations to so-called marker allergens represented by important pollen major allergens: Bet v 1 for the birch and beech family (Fagales), Ole e 1 for olive and ash (Oleaceae), Phl p 1 for temperate climate grasses (Poaceae), Art v 1 for mugwort (Artemisia), Amb a 1 for Ambrosia species (Ambrosia). Five typical cases (A – E) with positive skin prick test results to tree, grass, and weed pollen extracts demonstrate typical patterns of IgE sensitization with a variable impact of pollen panallergens: A – profilins, B – polcalcins, C – profilins and polcalcins, D – presumably cyclophilins, E – primary polysensitization to tree, grass, and weed pollen without interference from profilins or polcalcins. Differences between pollen extract-based skin prick test diagnosis and molecular allergen-specific IgE testing are explained using the presented concept. This approach allows to reduce the number of allergen extracts – presuming they are also clinically relevant – for allergen immunotherapy (i.e., only tree and/or grass pollen extracts), particularly in pollen-polysensitized patients.

Identification and Characterization of IgE-Reactive Proteins and a New Allergen (Cica1.01) from Chickpea (Cicer arietinum).

Chickpea (Cicer arietinum) allergy has frequently been reported particularly in Spain and India. Nevertheless, chickpea allergens are poorly characterized. The authors aim to identify and characterize potential allergens from chickpea. Candidate proteins are selected by an in silico approach or immunoglobuline E (IgE)-testing. Potential allergens are prepared as recombinant or natural proteins and characterized for structural integrity by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), circular dichroism (CD)-spectroscopy, and mass spectrometry (MS) analysis. IgE-sensitization pattern of Spanish chickpea allergic and German peanut and birch pollen sensitized patients are investigated using chickpea extracts and purified proteins. Chickpea allergic patients show individual and heterogeneous IgE-sensitization profiles with extracts from raw and boiled chickpeas. Chickpea proteins pathogenesis related protein family 10 (PR-10), a late embryogenesis abundant protein (LEA/DC-8), and a vicilin-containing fraction, but not 2Salbumin, shows IgE reactivity with sera from chickpea, birch pollen, and peanut sensitized patients. Remarkably, allergenic vicilin, DC-8, and PR-10 are detected in the extract of boiled chickpeas. Several IgE-reactive chickpea allergens are identified. For the first time a yet not classified DC-8 protein is characterized as minor allergen (Cica1). Finally, the data suggest a potential risk for peanut allergic patients by IgE cross-reactivity with homologous chickpea proteins.

Allergy immunotherapy: Future directions for the 2020s.

Allergy immunotherapy (AIT), whether administered as subcutaneous immunotherapy or as sublingual immunotherapy (SLIT), is an effective treatment for sensitization to inhalant allergens. There remain, however, some important unresolved issues, such as the need for compelling evidence for or against the efficacy of treatment with multiple unrelated allergen extracts and optimal dosing with SLIT-liquid preparations. Both methods of AIT involve prolonged periods of treatment to achieve persisting benefit. This can be inconvenient and expensive, and failure to complete the period of prescribed treatment is common with both methods. New approaches are being developed and studied to make AIT more effective, safer, or more convenient. Among these approaches are using alternative routes of administration; using adjuvants, including vitamin D, Toll-like receptor ligand agonists, biologics, or probiotics; introducing additional SLIT tablets; defining the patterns of major and minor allergen sensitivity of patients and the content of allergen extracts to better match sensitization with treatment; and treating cats to reduce their allergen release. The allergen molecules themselves are being altered to make them less reactive with specific immunoglobulin E, both by creating allergoids and by using recombinant technology to produce modified allergen molecules. Which, if any, of these new approaches will become part of AIT practice in the next decade depends in part on their efficacy and in part on the availability of the resources to adequately study them.