R-mandelonitrile-lyase, homolog to Pru d 10, is a major peach allergen in peach allergic Spanish population.

BACKGROUND AND OBJECTIVE: Peach allergy is a prevalent cause of food allergy. Despite the repertoire of allergens available for molecular diagnosis, there are still patients with undetectable IgE levels to peach allergens but presenting symptoms after its ingestion. The objective of this study was to investigate the allergenic profile in a patient population with symptoms produced by peach. METHODS: An exploratory retrospective study was performed with patients presenting symptoms after the ingestion of peach. Forty-two patients were included in the study. The allergenic profile of individual patients was investigated by immunoblot. A serum pool was prepared with the sera that recognized a 70 kDa band. This pool was used to detect this protein in peach peel and pulp and to identify the 70 kDa protein in 2D immunoblot. Spots recognized in the 2D immunoblot were sequenced by LC-MS/MS. Inhibition studies were performed between peach peel and almond. RESULTS: Twenty-two patients (52.4%) recognized the 70 kDa protein in immunoblot. This protein was recognized in peel and pulp. Two different spots were observed in 2D-PAGE, both were identified as (R)-mandelonitrile lyases (RML) with high amino acid similarity with Pru du 10. Peach RML were partially inhibited with an almond extract. No association was found between any reported symptom and sensitization to RML. RML-sensitized patients were older and reported pollen associated respiratory symptoms more frequently than negative patients. CONCLUSION: A new peach allergen, a RML, homologous of Pru du 10, recognized by 52% of the population has been identified.

Sensitization to Vitis vinifera Pollen in a Wine Production Area: Identification of the Allergens Involved.

BACKGROUND: Vine cultivation is widely distributed in La Rioja, Spain (37% of all crops) and is associated with exposure of the general population to vine pollen. The aims of this study were to investigate the prevalence of sensitization to Vitis vinifera pollen in persons with respiratory allergy in the general population and to identify the allergens involved. MATERIALS AND METHODS: The study population comprised patients who came to the hospital between September 2019 and January 2020 with suspected respiratory allergy. All patients underwent skin prick testing with a panel of standardized aeroallergens, profilin, lipid transfer protein (LTP), and V vinifera pollen extract and prick-prick testing with fresh grapes. The in vitro study included specific IgE by ImmunoCap and ELISA, allergenic profile by immunoblot with individual sera from patients positive to V vinifera pollen extract, and 2D immunoblot with a pool of sera. The spots recognized by IgE were identified using mass spectrometry. RESULTS: A total of 151 patients were included. Of these, 124 were positive to some of the allergens tested. Thirty-four (27.4%) were positive to vine pollen in the skin prick tests. The serology study revealed positive results in 20 patients. Five vine pollen allergens were identified, and profilin was the most prevalent (30%). The other 4 allergens could be considered specific to this pollen. CONCLUSIONS: Sensitization to vine pollen was frequent in the general population in a vine growing area. The clinical relevance of this finding is unknown owing to sensitization to other pollens in the vine pollen-positive patients. Five new vine pollen allergens were identified.

Sensitization to Vitis vinifera Pollen in a Wine Production Area: Identification of the Allergens Involved

Background: Vine cultivation is widely distributed in La Rioja, Spain (37% of all crops) and is associated with exposure of the general population to vine pollen. The aims of this study were to investigate the prevalence of sensitization to Vitis vinifera pollen in persons with respiratory allergy in the general population and to identify the allergens involved. Materials and Methods: The study population comprised patients who came to the hospital between September 2019 and January 2020 with suspected respiratory allergy. All patients underwent skin prick testing with a panel of standardized aeroallergens, profilin, lipid transfer protein (LTP), and V vinifera pollen extract and prick-prick testing with fresh grapes. The in vitro study included specific IgE by ImmunoCap and ELISA, allergenic profile by immunoblot with individual sera from patients positive to V vinifera pollen extract, and 2D immunoblot with a pool of sera. The spots recognized by IgE were identified using mass spectrometry. Results: A total of 151 patients were included. Of these, 124 were positive to some of the allergens tested. Thirty-four (27.4%) were positive to vine pollen in the skin prick tests. The serology study revealed positive results in 20 patients. Five vine pollen allergens were identified, and profilin was the most prevalent (30%). The other 4 allergens could be considered specific to this pollen. Conclusions: Sensitization to vine pollen was frequent in the general population in a vine growing area. The clinical relevance of this finding is unknown owing to sensitization to other pollens in the vine pollen–positive patients. Five new vine pollen allergens were identified (AU)

Antecedentes: El cultivo de la vid está ampliamente distribuido en La Rioja (37% de los cultivos), lo que supone una exposición de la población general al polen de esta planta. El objetivo de este estudio fue investigar la prevalencia de sensibilización al polen de Vitis vinifera en la población general con alergia respiratoria e identificar los alérgenos implicados. Materiales y métodos: Se incluyeron en el estudio pacientes que acudieron al hospital entre septiembre de 2019 y enero de 2020 con sospecha de alergia respiratoria. A todos ellos se les realizó una prueba cutánea con el panel de aeroalérgenos estandarizados, profilina, LTP, extracto de polen de V. vinifera y Prick prick con uva. El estudio in vitro incluyó IgE específica mediante ImmunoCap y ELISA, perfil alergénico por inmunoblot con sueros individuales de pacientes positivos al extracto de polen de V. vinifera e inmunoblot 2D con un pool de sueros. Las proteínas reconocidas por la IgE fueron identificadas por espectrometría de masas. Resultados: Se incluyeron un total de 151 pacientes. De ellos, 124 fueron positivos a algunos de los alérgenos analizados. 34 (27,4%) fueron positivos a polen de vid por prueba cutánea. 20 fueron positivos tras el estudio serológico. Se identificaron 5 alérgenos del polen de la vid, siendo la profilina el más prevalente (30%). Los otros 4 alérgenos podrían considerarse específicos de este polen. Conclusión: Se detectó una alta sensibilización al polen de vid en la población general en una zona de viñedos. Se desconoce la relevancia clínica debido a la sensibilización a otros pólenes en los pacientes positivos a polen de vid. Se identificaron 5 nuevos alérgenos del polen de la vid (AU)

Relevance of Allergenic Sensitization to Cynodon dactylon and Phragmites communis: Cross-reactivity With Pooideae Grasses.

BACKGROUND AND OBJECTIVES: The homologous group of sweet grasses belongs to the Pooideae subfamily, but grass pollen species from other subfamilies can also cause allergy, such as Cynodon dactylon (Chloridoideae) and Phragmites communis (Arundinoideae). C dactylon and P communis have not been included in the sweet grasses homologous group because of their low cross-reactivity with other grasses. The aims of this study were to investigate the profile of sensitization to C dactylon and P communis in patients sensitized to grasses and to analyze cross-reactivity between these 2 species and temperate grasses. METHODS: Patients were skin prick tested with a grass mixture (GM). Specific IgE to GM, C dactylon, P communis, Cyn d 1, and Phl p 1 was measured by ImmunoCAP. A pool of sera was used for the immunoblot assays. Cross-reactivity was studied by ELISA and immunoblot inhibition. RESULTS: Thirty patients had sIgE to GM. Twenty-four (80%) had positive results for C dactylon, 27 (90%) for P communis, 22 (73.3%) for nCyn d 1, and 92.9% for rPhl p 1. Bands were detected in the 3 extracts by immunoblot. Inhibition of GM was not observed with C dactylon or P communis by immunoblot or ELISA inhibition. When C dactylon or P communis were used in the solid phase, GM produced almost complete inhibition. CONCLUSIONS: Eighty percent of patients sensitized to grasses were also sensitized to C dactylon and 90% were sensitized to P communis. Sensitization to these species seems to be induced by allergens different to those in sweet grasses.

Tomato nsLTP as an "In Vivo" Diagnostic Tool: Sensitization in a Mediterranean Population.

BACKGROUND: Tomato allergies have been extensively studied but component-resolved in vivo diagnosis with purified allergens has yet to be performed. OBJECTIVES: To evaluate the prevalence of sensitization to Sola l 3 in a Mediterranean population, and to compare the resulting sensitization profile with that of individuals sensitized to tomato, peach, and/or purified lipid transfer protein (LTP). METHODS: Sola l 3 was purified, characterized, and used to prepare skin prick tests (SPTs). Two groups of patients were selected. Group 1 consisted of patients with at least 1 positive SPT to tomato, peach, or LTP mixture (marker extracts) who were subsequently tested with Sola l 3 (n = 280). Group 2 (prevalence study) consisted of patients who underwent simultaneous SPT with the 3 marker extracts and Sola l 3 (n = 658). Patients from either group who were positive to any of the 4 extracts were studied in detail (study group, n = 1 23). ELISA and immunoblot assays were performed in individuals with a positive SPT to Sola l 3 to detect the presence of specific IgE antibodies to this allergen. RESULTS: Prevalence of sensitization to Sola l 3 was 3.2% overall and 54.7% in tomato-positive patients. Most tomato-sensitized patients were asymptomatic. Symptoms were more common in Sola l 3-positive individuals. Sensitization to peach and the LTP mixture did not discriminate between Sola l 3-positive and Sola l 3-negative patients. CONCLUSIONS: This study confirms that LTP, not only from peach but also from other fruit and vegetables, including tomato, is an important allergen in the Mediterranean area. Sensitization to Sola l 3 is associated with more symptoms in tomato-sensitized patients.

Allergy to goat and sheep cheese with tolerance to cow's milk and its derivatives.

OBJECTIVE: We present two adult and three paediatric patients who had allergic reactions after cheese ingestion and subsequently tolerated cow's milk derivatives. The objective of this study was to determine possible cross-reactivity between different types of cheese. METHODS: Skin tests were performed to cow's milk fractions, and prick-prick tests for goat, sheep and cow cheese. Specific IgE to the fractions of cow's milk and cow, sheep and goat cheese was analysed. The protein profile of cow, sheep and goat cheese extracts was determined by SDS-PAGE and the allergenic profile by immunoblot. Cross-reactivity was investigated by immunoblot inhibition. RESULTS: Skin tests were positive for casein in the patients. The prick-prick tests were positive for the three cheeses in patients 1 and 4, for goat and sheep cheese in patients 2 and 3, and for sheep cheese in patient 5. The specific IgE test was positive in patients 1, 3 and 4 for goat and sheep cheese, and negative in patients 2 and 5. Serum 3 and 4 clearly recognised goat and sheep cheese extracts. Goat casein was almost completely inhibited with sheep casein and partially inhibited with goat and sheep serum proteins, while there was no inhibition with cow cheese. Sheep casein was totally inhibited with sheep serum proteins. Sheep casein was inhibited with goat and cow caseins, suggesting cross-reactivity among the three types of cheese. CONCLUSIONS: We showed sensitisation to goat and sheep cheese in two patients, and only to sheep cheese in another two of the studied patients.

Goji berries (Lycium barbarum): risk of allergic reactions in individuals with food allergy.

BACKGROUND: New foods are frequently introduced in Western diets for their healthy properties; however, they may produce adverse effects. OBJECTIVE: After attending a patient who experienced an allergic reaction to Goji berries, we evaluated the allergenic potential of this food in plant food-allergic individuals, a group that is considered to be at high risk of experiencing a reaction. METHODS: We recruited 30 additional plant food-allergic individuals in Spain during 3 months in 2010. Four patients reported symptoms on intake, 6 tolerated the berries, and 20 had never tried Goji berries. Patients underwent skin prick tests with Goji berries, as well as with peach peel and plant food panallergens as markers of cross-reactivity between unrelated foods. We carried out in vitro tests in symptomatic patients. RESULTS: Skin tests to Goji berries were positive in 24 patients (77%): 5 symptomatic patients and 19 asymptomatic patients. Positivity to Goji berries was associated with positivity to peach peel and to the panallergen nonspecific lipid transfer protein (LTP). Nearly half of the patients reported symptoms (45%), but 89% of the skin test-positive patients had never eaten Goji berries. We detected specific immunoglobulin E to Goji berries in all cases, and several individuals recognized 2 protein bands in the immunoblot. Addition of LTP to sera mostly inhibited immunoglobulin E binding to an LTP-like band, suggesting a role for this panallergen in sensitization to Goji berries. CONCLUSIONS: Our results demonstrate the allergenic potential of Goji berries in high-risk individuals, which is probably due to cross-reactivity with LTP from other foods. The risks of Goji berries should be taken into consideration in individuals with food allergy, especially those who are allergic to LTP.

Immunogenicity of Phleum pratense depigmented allergoid vaccines: experimental study in rabbits.

BACKGROUND: Immunogenicity studies are based on accurate preclinical and clinical assessment of pharmaceutical products. The immunogenicity of modified allergen vaccines has not been fully elucidated, and the mechanisms involved are not well understood. Animal and human models have recently shown that depigmented allergoids induce specific immunoglobulin (Ig) G against individual allergens, thus supporting the clinical efficacy of these vaccines. OBJECTIVE: The aim of this study was to investigate the production of specific IgG against individual antigens and their isoforms in rabbits injected with depigmented allergoid extracts of Phleum pratense pollen. METHODS: Two New Zealand rabbits were immunized with depigmented-polymerized extracts adsorbed onto aluminum hydroxide (Depigoid) of P pratense. Rabbits were injected 3 times (35 microg Phl p 5). Specific IgG titers against native, depigmented, and depigmented-polymerized extracts and individual allergens (rPhl p 1 and rPhl p 5a) were analyzed by direct enzyme-linked immunosorbent assay. The capacity of these synthesized antibodies to recognize individual native and depigmented allergens and different isoforms was evaluated by immunoblot and 2-D analysis. RESULTS: All rabbits produced high titers of specific IgG against the 3 extracts. Rabbits injected with depigmented allergoids produced similar specific antibody titers against native, depigmented, and depigmented-polymerized extracts. Serum samples recognized individual allergens and their isoforms in the nonmodified extracts. CONCLUSION: Vaccines containing depigmented allergoid extracts of P pratense induce immunogenicity in vivo. The antibodies produced after injection of these extracts clearly recognized allergens and different isoforms in their native configuration.

Anaphylaxis associated with the ingestion of Goji berries (Lycium barbarum).

Goji berry (wolfberry), a member of the Solanacea family, has been recently introduced in Western countries and its consumption has increased rapidly. The objectives of the study were to describe the cases of 2 patients who experienced allergic symptoms after Goji berry consumption, to identify the protein profile of the extract, to analyze the allergenic profile of individuals, and to determine cross-reactivity with other members of the Solanaceae family (tomato). We describe 2 cases of allergic reaction, 1 of which was an anaphylactic reaction, after Goji berry ingestion. A Goji berry extract was manufactured and immunochemically characterized. The patients were skin prick tested with a battery of common aeroallergens including mites, epithelia, and molds. Individuals were also skin prick tested with food allergens, including Goji berries. A positive skin prick test and specific immunoglobulin (Ig) E to Goji berry was detected in both cases. Serum samples recognized a 9-kDa band, probably related to lipid transfer proteins (LTPs). Cross-reactivity with tomato was analyzed by inhibition studies, which showed that the 9-kDa band was totally inhibited by the tomato extract. This study describes the first 2 cases of allergic reaction following Goji berry ingestion. LTPs seem to be involved in allergic sensitization to Goji berries, as evidenced by cross-reactivity with tomato.

Acidic ribosomal protein 60S: A new tomato allergen.

Three tomato allergens (Lyc e 1, Lyc e 2 and Lyc e 3) have been characterised until now. Previous studies have demonstrated the existence of other proteins with capacity to bind IgE. The objective of this study was to identify new tomato allergens by molecular biology techniques. A tomato peel cDNA library was screened using a specific pool of sera from sensitised individuals. A clone was obtained and its sequence compared to other described allergens. This clone contained 34 aminoacids from the C-terminal region of an acidic ribosomal protein 60S. This protein showed more than 85% of homology with fungal allergens and 93.8% of homology with the almond allergen Pru du 5. The clone also contains 169 base pairs without homology with other known genes and could correspond to non-coding sequences. The IgE detection with a pool of sera was positive which confirms that is a new tomato allergen.

Allergenic differences among pollens of three Salsola species.

BACKGROUND: Sensitivity to Chenopodiaceae is a frequent cause of allergic respiratory diseases in geographic areas where sensitization to Salsola kali and Chenopodium album has been reported. The objective of this study was to evaluate the pattern of sensitization to 3 Salsola species in patients residing on the Mediterranean coast of south-eastern Spain. METHODS: S. kali, S. vermiculata and S. oppositifolia pollen extracts were prepared. Patients reporting respiratory and/or cutaneous symptoms were skin prick tested with the 3 Salsola extracts. Individuals with positive skin prick tests to at least 1 of the 3 Salsola species were included. Specific IgE was determined by direct ELISA. SDS-PAGE and 2-D analysis were conducted to elucidate the protein profile. The allergenic profile was investigated by immunoblot. Inhibition experiments were conducted to establish cross-reactivity between different species. RESULTS: 246 patients were included. 237 patients (96.3%) tested positive to S. oppositifolia, 189 (76.8%) to S. kali and 185 (75.2%) to S. vermiculata. Protein profile and immunoblot demonstrated similar patterns in all extracts, except in low-molecular-weight allergens of S. oppositifolia. Immunoblot inhibition experiments demonstrated that most high-molecular-weight allergens of S. oppositifolia were inhibited by S. kali whereas low-molecular-weight allergens were totally inhibited only by C. album. CONCLUSIONS: This study confirms the allergenic importance of other Salsola species, especially S. oppositifolia. We have demonstrated that the 3 species show a high degree of cross-reactivity, but S. oppositifolia shares more allergenic similarities with C. album than S. kali.

Sensitization to tomato peel and pulp extracts in the Mediterranean Coast of Spain: prevalence and co-sensitization with aeroallergens.

BACKGROUND: Tomatoes (Lycopersicon esculentum) are consumed world-wide. The prevalence of sensitization to tomatoes remains unknown. OBJECTIVE: To determine the prevalence of skin test reactivity to tomato and to describe the characteristics of tomato-sensitized subjects. METHODS: Individuals attending for the first time during the period of the study to six Allergy centres, located along the Mediterranean coast of Spain, reporting respiratory and/or cutaneous symptoms, were included. All patients were skin prick tested with a battery of inhalant allergens and with peel and pulp of Canary tomato extracts. RESULTS: The study included 1734 individuals (757 males, 977 females; 31.9+/-17.8 years old). The prevalence of sensitization to tomato was 6.52% (113 patients; 65 males, 48 females; 29.5+/-13 years old). The peel extract was positive in 110 patients and the pulp extract in 47 patients; three patients were positive exclusively to pulp. Only 1.8% of individuals reported symptoms with tomato; 44% of them had skin test negative to both extracts. Among tomato-sensitized subjects, 16% reported symptoms with tomato, 97% were sensitized to inhalant aeroallergens, including 84% to pollens (mainly Artemisia vulgaris and Platanus hybrida), with differences between Northern and Southern centres. CONCLUSIONS: The prevalence found of skin test sensitivity to tomato is high. Peel extracts detected most of the sensitized subjects. Most of the sensitized subjects were asymptomatic and some patients reported symptoms without skin test sensitivity. Positive subjects were very frequently sensitized to pollens, suggesting allergen cross-reactivity. Regional differences may exist, possibly related to the pattern of sensitization to cross-reacting pollens.

Mcchs1, a member of a chitin synthase gene family in Mucor circinelloides, is differentially expressed during dimorphism.

A complete chitin synthase gene and one chitin synthase gene fragment of the zygomycete Mucor circinelloides have been cloned and analyzed. Both genes encode zymogenic Class II chitin synthases. Hybridization analysis showed that there must exist at least another Class II chitin synthase gene in M. circinelloides highly homologous to the cloned Mcchs1 and Mcchs2. The expression of these genes during the dimorphic growing stages was analyzed. Northern hybridizations showed that Mcchs1 transcript accumulates only during the exponentially growing hyphal stage, while no expression could be detected in the yeast form. Expression of Mcchs2 could not be detected at any stage. Accumulation of Mcchs1 transcript was not influenced by visible light. The existence of a multigene chitin synthase family and the observation that Mcchs1 transcription depends upon the dimorphic stage indicate that various chitin synthase activities may have different roles in the dimorphic growth of M. circinelloides.