ABSTRACT
BACKGROUND: Prosopis juliflora is a clinically relevant allergic sensitizer worldwide and shares cross-reactivity with allergens from several tree pollen and food. The present study aims to purify and immunobiochemically characterize a major allergen from Prosopis pollen. The allergen was further investigated for its cross-reactivity with legume allergens. METHODS: Prosopis extract was fractionated by Q Sepharose and Superdex 75 gel filtration column to purify the allergen. Specific IgE against purified protein was estimated via ELISA and immunoblot. The protein was subjected to mass spectrometric analysis. Glycan characterization was performed by Schiff staining and lectin binding assay followed by deglycosylation studies. The functional activity of the purified protein was evaluated by the basophil activation test. Cross-reactivity was assessed by inhibition studies with legume extracts. RESULTS: A 35 kDa protein was purified and showed 75% IgE reactivity with the patients' sera by ELISA and immunoblot. Glycan characterization of protein demonstrated the presence of terminal glucose and mannose residues. A reduction of 40% and 27% in IgE binding was observed upon chemical and enzymatic deglycosylation of the protein, respectively. The glycoprotein allergen upregulates the expression of CD203c on basophils which was significantly reduced upon deglycosylation, signifying its biological ability to activate the effector cells. The identified protein shared significant homology with Lup an 1 from the lupine bean. Immunoblot inhibition studies of the purified allergen with legume extracts underlined high cross-reactive potential. Complete inhibition was observed with peanut and common bean, while up to 70% inhibition was demonstrated with soy, black gram, chickpea, and lima bean. CONCLUSION: A 35 kDa vicilin-like major allergen was isolated from P. juliflora. The protein possesses glycan moieties crucial for IgE binding and basophil activation. Furthermore, the purified protein shows homology with Lup an 1 and exhibits cross-reactivity with common edible legume proteins.
Subject(s)
Allergens/immunology , Cross Reactions/immunology , Fabaceae/immunology , Prosopis/immunology , Seed Storage Proteins/immunology , Antigens, Plant/immunology , Arachis/immunology , Basophils/immunology , Female , Food Hypersensitivity/immunology , Humans , Immunoglobulin E/immunology , Male , Plant Proteins/immunology , Pollen/immunology , Skin Tests/methodsABSTRACT
Some herbivores suppress plant defenses, which may be viewed as a result of the coevolutionary arms race between plants and herbivores. However, this ability is usually studied in a one-herbivore-one-plant system, which hampers comparative studies that could corroborate this hypothesis. Here, we extend this paradigm and ask whether the herbivorous spider-mite Tetranychus evansi, which suppresses the jasmonic-acid pathway in tomato plants, is also able to suppress defenses in other host plants at different phylogenetic distances from tomatoes. We test this using different plants from the Solanales order, namely tomato, jimsonweed, tobacco, and morning glory (three Solanaceae and one Convolvulaceae), and bean plants (Fabales). First, we compare the performance of T. evansi to that of the other two most-commonly found species of the same genus, T. urticae and T. ludeni, on several plants. We found that the performance of T. evansi is higher than that of the other species only on tomato plants. We then showed, by measuring trypsin inhibitor activity and life history traits of conspecific mites on either clean or pre-infested plants, that T. evansi can suppress plant defenses on all plants except tobacco. This study suggests that the suppression of plant defenses may occur on host plants other than those to which herbivores are adapted.
Subject(s)
Acari/pathogenicity , Adaptation, Physiological , Host-Parasite Interactions , Plant Immunity , Acari/genetics , Acari/metabolism , Animals , Fabaceae/immunology , Fabaceae/parasitology , Host Specificity , Life History Traits , Solanum tuberosum/immunology , Solanum tuberosum/parasitology , Nicotiana/immunology , Nicotiana/parasitology , Trypsin Inhibitors/metabolismABSTRACT
Inflammation is part of the non-specific immune response that occurs in reaction to any type of bodily injury. In some disorders the inflammatory process, which under normal conditions is self-limiting, becomes continuous and chronic inflammatory diseases develop subsequently including cardiovascular diseases, diabetes, cancer etc. Barks of Delonix regia is used traditionally in the treatment of inflammatory diseases. Therefore, in this study we evaluated the therapeutic potential of D. regia ethanol extract and its active constituent ß-Elemene with special interest in inflammation model using standard in vivo anti-inflammatory models: Carrageenan-induced paw edema, Cotton pellet granuloma, and Acetic acid-induced vascular permeability. To explicate the mechanism of action for the possible anti-inflammatory activity, we determined the level of major inflammatory mediators (NO, iNOS, COX-2-dependent prostaglandin E2 or PGE2), and pro-inflammatory cytokines (TNF-a, IL-1b, IL-6, and IL-12). Additionally, we determined the toll-like receptor 4 (TLR4), Myeloid differentiation primary response gene 88 (MyD88), by mRNA expression in drug treated LPS-induced murine macrophage model. To explore the mechanism of anti-inflammatory activity, we evaluated expression of c-Jun N-terminal kinases (JNK), nuclear factor kappa-B cells (NF-kB), and NF-kB inhibitor alpha (IK-Ba). Furthermore, we determined the acute and sub-acute toxicity of D. regia extract in BALB/c mice. This study established a significant anti-inflammatory activity of D. regia extract and ß-Elemene along with the inhibition of TNF-a, IL-1b, IL-6 and IL-12 expressions. Further, the expression of TLR4, NF-kBp65, MyD88, iNOS and COX-2 molecules were reduced in drug-treated groups, but not in the LPS-stimulated untreated or control groups, Thus, our results collectively indicated that the D. regia extract and ß-Elemene can efficiently inhibit inflammation.
Subject(s)
Anti-Inflammatory Agents/therapeutic use , Edema/drug therapy , Granuloma/drug therapy , Plant Extracts/therapeutic use , Sesquiterpenes/therapeutic use , Acetic Acid , Animals , Capillary Permeability/drug effects , Carrageenan , Cyclooxygenase 2 , Cytokines , Disease Models, Animal , Fabaceae/immunology , Inflammation Mediators , Mice , Mice, Inbred BALB C , Rats , Rats, Wistar , Signal Transduction/drug effects , Toll-Like Receptor 4/metabolismABSTRACT
On the basis of in vitro and in vivo investigations trans-resveratrol (RV) is a natural, concentration-dependent formaldehyde (HCHO) mobilizer, scavenger, capture and carrier molecule. The capturing and mobilization of HCHO from a given biological unit (e.g. tissue) with RV (first step) generates a chemopreventive effect. The reaction products between endogenous HCHO and RV (second step) may exert killing/inhibiting effects on pathogens and/or cancer cells. These two steps result in the double effect of RV. From the model reaction mixture of RV and HCHO in diluted formalin solution, different reaction products were detected, separated and identified. Similar reactions can be observed between RV and endogenous HCHO in plant and animal tissues as well. Capturing the HCHO molecules in model experiments with HCHO-capture molecules (in vitro conditions) the antibacterial activity of RV decreased substantially. The in vitro investigations were extended to in vivo conditions. The discovery of a quadruple immune response of plants to pathogens resulting from pretreatment with RV opens new horizons in the confirmation of the diverse beneficial effects of RV.
Subject(s)
Formaldehyde/chemistry , Stilbenes/chemistry , Anti-Bacterial Agents/pharmacology , Basidiomycota , Fabaceae/drug effects , Fabaceae/immunology , Models, Chemical , Pseudomonas/drug effects , Resveratrol , Stilbenes/pharmacologyABSTRACT
BACKGROUND: Peltophorum pterocarpum (yellow gulmohar, PP) pollen is an important aeroallergen for type I hypersensitivity in the tropics. OBJECTIVE: To isolate and characterize the IgE-binding proteins of PP pollen for the first time. METHODS: Pollen extract was fractionated by a combination of Sephacryl S-200 column and diethylaminoethyl-Sephadex column. Allergen characterization was done by sodium dodecyl sulphate polyacrylamide gel electrophoresis, periodic acid-Schiff staining, enzyme-linked immunosorbent assay, and western blotting. Allergenic activities were determined by in vivo (skin prick test) and in vitro (enzyme-linked immunosorbent assay and histamine release) analyses. To determine whether the carbohydrate chains are involved in immunoreactivity, deglycosylation of PP pollen proteins was performed. RESULTS: SPT results on the respiratory allergic patients of Calcutta showed that 32.77% showed positivity with PP pollen. Eight IgE-reactive protein components were found in crude extract. Optimum IgE-reactive fraction 1 was resolved into five subfractions. The subfraction 1a showed maximum IgE reactivity containing the 28 kDa IgE-reactive component. Periodate oxidation showed that protein component was involved in its IgE binding. Twenty-eight kilodalton IgE reactive protein component was recognized by 75% of PP-sensitive patients in Western blotting. It also induced significant histamine release in sensitive patient sera. CONCLUSIONS: The purified 28 kDa protein is a clinically relevant allergen with a potential for diagnosis and therapy of patients susceptible to PP pollen.
Subject(s)
Fabaceae/immunology , Pollen/chemistry , Pollen/immunology , Trees/immunology , Adolescent , Adult , Allergens/immunology , Allergens/isolation & purification , Blood/immunology , Blood/metabolism , Blotting, Western , Chromatography, Gel , Chromatography, Ion Exchange , Female , Histamine Release/immunology , Humans , Immunoglobulin E/blood , Immunoglobulin E/immunology , India , Male , Middle Aged , Plant Extracts/chemistry , Plant Extracts/immunology , Plant Proteins/immunology , Plant Proteins/isolation & purification , Respiratory Hypersensitivity/immunology , Skin Tests , Young AdultABSTRACT
BACKGROUND: Delonix regia and Peltophorum pterocarpum pollen are important aeroallergens for type 1 hypersensitivity in the tropics. The IgE-binding proteins of D regia and their cross-allergenity with P pterocarpum pollen have not been evaluated. OBJECTIVES: To isolate and characterize the IgE-binding proteins of D regia pollen for the first time and to investigate the cross-allergenity with P pterocarpum pollen belonging to the same family (Leguminosae). METHODS: Allergenic activities were determined by in vivo and in vitro analyses. Pollen extract was fractionated by a combination of 2 columns (diethyl amino ethyl Sephadex and Sephacryl S-200). Protein components were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, periodic acid-Schiff staining, and immunoblotting. In vitro inhibition tests were performed to evaluate the cross-reactivity. RESULTS: The skin prick test results of the patients with respiratory allergies in Calcutta, India, showed 31.1% positivity with D regia pollen. Nine IgE-reactive protein components were found in the crude extract. An optimum IgE-reactive fraction was resolved into 4 subfractions. Subfraction A, which showed maximum IgE reactivity, contained 2 (96- and 66-kDa) IgE-reactive protein components. The 66-kDa component was found to be glycoprotein. Remarkable cross-reactivity between D regia and P pterocarpum pollen was found on IgE enzyme-linked immunosorbent assay inhibition and dot blotting. Shared IgE-binding components (66, 56, 32, 28, 25, and 23 kDa) were observed between D regia and P pterocarpum pollen extracts, whereas the 96- and 43-kDa components were specific to D regia. CONCLUSION: The purification of the IgE-binding proteins and the identification of the shared/cross-reactive proteins in these taxonomically related pollen members should be helpful for the diagnosis and therapy of patients susceptible to these pollens.
Subject(s)
Cross Reactions/immunology , Fabaceae/immunology , Pollen/immunology , Respiratory Hypersensitivity/immunology , Trees/immunology , Adolescent , Adult , Antigens, Plant/analysis , Antigens, Plant/immunology , Asthma/immunology , Asthma/physiopathology , Binding, Competitive/immunology , Blotting, Western , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Female , Forced Expiratory Volume/physiology , Glycoproteins/analysis , Glycoproteins/immunology , Histamine Release/immunology , Humans , Hypersensitivity/diagnosis , Hypersensitivity/immunology , Immunoblotting , Immunoglobulin E/blood , Immunoglobulin E/immunology , India , Male , Middle Aged , Plant Extracts/chemistry , Plant Extracts/immunology , Plant Proteins/analysis , Plant Proteins/immunology , Pollen/chemistry , Respiratory Hypersensitivity/physiopathology , Rhinitis, Allergic, Seasonal/immunology , Rhinitis, Allergic, Seasonal/physiopathology , Skin Tests , Young AdultABSTRACT
BACKGROUND: Foods not commonly consumed in the European Union must be proven safe before being brought to market, including an assessment of allergenicity. We present a three-stepwise strategy for allergenicity assessment of natural novel foods using three novel vegetables, namely, water spinach, hyacinth bean, Ethiopian eggplant. METHODS: First, vegetable extracts were analyzed for the presence of pan-allergens [Bet v 1 homologous proteins, profilins, nonspecific lipid transfer proteins (LTP)] by immunoblot analysis with specific animal antibodies. Secondly, the IgE-binding of the food extracts was investigated by EAST (Enzyme-allergosorbent test) and immunoblot analysis using sera with IgE-reactivity to known pan-allergens or to phylogenetically related foods from subjects (i) allergic to birch, grass and mugwort pollen, (ii) with food allergy to soy, peanut, tomato, multiple pollen-related foods and (iii) sensitized to LTP. Thirdly, the clinical relevance of IgE-binding was assessed in vivo by skin prick testing (SPT) and open oral food challenges (OFC). RESULTS: Profilin and LTP were detected by animal antibodies in all vegetables, a Bet v 1 homologue selectively in hyacinth bean. IgE-binding to LTP, profilin and a Bet v 1 homologue was proven by immunoblot analysis and EAST. Positive SPT and OFC results were observed for all vegetables in pollen-allergic patients. CONCLUSIONS: Our stepwise procedure confirmed the presence and IgE-binding capacity of novel vegetable proteins homologous to known allergens in endemic vegetable foods. In vivo testing proved the potential of the novel vegetables to elicit clinical allergy. Hence, our described algorithm seems to be applicable for allergenicity testing of natural novel foods.
Subject(s)
Allergens/analysis , Allergens/immunology , Carrier Proteins/immunology , Food Hypersensitivity/immunology , Immunoassay/methods , Immunoglobulin E/immunology , Profilins/immunology , Vegetables/immunology , Carrier Proteins/analysis , European Union , Fabaceae/immunology , Food Hypersensitivity/blood , Humans , Ipomoea/immunology , Profilins/analysis , Skin Tests , Solanum/immunologyABSTRACT
Extracts of Jatoba, a South American herb, when injected i.p. into a mouse model of experimental autoimmune encephalomyelitis (EAE), inhibited the aggravation of clinical symptoms. At the same time, production of myelin oligodendrocyte glycoprotein Ag-specific IFN-gamma and TNF-alpha by spleen cells was markedly suppressed. After administration of Jatoba there was minimal evidence of the demyelination that is characteristic of the EAE model. Decreases in clinical scores were observed when Jatoba extracts were injected just before Ag. The purified active compounds are likely to be polyphenols that are absorbable to polyvinylpolypyrrolidone. The active compounds were polymerized polyphenol polymers (procyanidins) and at least five degrees of polymerization were necessary for activity. In addition, extracts of other plant materials containing such procyanidins had similar activity. After administration of highly polymerized procyanidins, there was a decrease in both dendritic and CD4(+) T cells. Although macrophages were increased in number, the expression of CD80 and MHC class II molecules was depressed indicating that the macrophages were immature. The results indicate that the suppression of development of EAE by the highly polymerized procyanidins resulted from an inhibition of Th1 and the effects might be associated with depression of Ag-presenting capability.
Subject(s)
Biflavonoids/pharmacology , Catechin/pharmacology , Encephalomyelitis, Autoimmune, Experimental/drug therapy , Encephalomyelitis, Autoimmune, Experimental/immunology , Immunosuppressive Agents/pharmacology , Proanthocyanidins/pharmacology , Th1 Cells/drug effects , Th1 Cells/immunology , Animals , Biflavonoids/administration & dosage , Catechin/administration & dosage , Encephalomyelitis, Autoimmune, Experimental/pathology , Fabaceae/immunology , Flavonoids/administration & dosage , Flavonoids/pharmacology , Immunosuppressive Agents/administration & dosage , Male , Mice , Mice, Inbred C57BL , Phenols/administration & dosage , Phenols/pharmacology , Physalis/immunology , Plant Extracts/administration & dosage , Plant Extracts/pharmacology , Polyphenols , Proanthocyanidins/administration & dosage , Th1 Cells/metabolism , Uncaria/immunologyABSTRACT
A novel triterpenoidal saponin, called pulcherrimasaponin (CP05), isolated from the leaves of Calliandra pulcherrima Benth. shows remarkable similarities to the previously described potent adjuvant, QS21 saponin (Quillaja saponaria Molina). On the basis of chemical and physicochemical evidence, its structure was established as [3beta,16alpha,28[2E,6S[2E,6S(2E,6S)]]]-olean-12-en-28-oic acid 3-[[O-alpha-l-arabinopyranosyl-(1-->2)-O-alpha-l-arabinopyranosyl-(1-->6)-2-(acetylamino)-2-deoxy-beta-d-glucopyranosyl]oxy]-16-hydroxy-O-beta-d-glucopyranosyl-(1-->3)-O-[O-beta-d-xylopyranosyl-(1-->3)-beta-d-xylopyranosyl-(1-->4)-O-6-deoxy-alpha-l-mannopyranosyl-(1-->2)-6-O-[6-[[2-O-2,6-dimethyl-1-oxo-6-(beta-d-xylopyranosyloxy)-2,7-octadienyl]-[(6-deoxy-beta-d-glucopyranosyl)oxy]-2,6-dimethyl-1-oxo-2,7-octadienyl]-beta-d-xylopyranosyl]oxy]-2,6-dimethyl-1-oxo-2,7-octadienyl]-beta-d-glucopyranosyl ester. In vivo toxicity assays disclosed similar and transitory local swelling and loss of hair but no lethality for mice. The haemolytic index was higher for QS21 (5 microg/ml) than for CP05 (13 microg/ml). Mouse vaccination with either CP05 or QS21 in combination with the fucose-mannose ligand (FML) antigen of Leishmania donovani showed anti-FML responses, significantly enhanced over the saponin and saline controls, in IgM, IgG, IgG1, IgG2a, IgG2b and IgG3. Antibody levels were similar for both vaccines in most subtypes. However, QS21-FML vaccine showed a 1.5 to 2.1 proportional increase over the CP05-FML vaccine in IgG, IgG2a and IgG3 responses. The delayed type of hypersensitivity against leishmanial antigen was impressively increased for CP05-FML and for QS21-FML-treated animals over controls (p<0.005). Enhancement was similar for both vaccines (p<0.05). The safety analysis and the effect on humoral and cellular immune responses demonstrated that the novel Calliandra pulcherrima Benth. CP05 saponin is a potential candidate for a vaccine adjuvant.
Subject(s)
Adjuvants, Immunologic/therapeutic use , Fabaceae/immunology , Immunization/methods , Leishmaniasis, Visceral/prevention & control , Protozoan Vaccines/immunology , Saponins/chemistry , Adjuvants, Immunologic/isolation & purification , Animals , Antibodies, Protozoan/biosynthesis , Cricetinae , Disease Models, Animal , Fabaceae/chemistry , Female , Humans , Leishmaniasis, Visceral/immunology , Leishmaniasis, Visceral/parasitology , Mice , Mice, Inbred BALB C , Plant Extracts/immunology , Plant Extracts/isolation & purification , Plant Extracts/therapeutic use , Plant Leaves , Protozoan Vaccines/administration & dosage , Quillaja/immunology , Saponins/immunologyABSTRACT
Legumes are dicotyledonous plants belonging to the Fabales order. The main distinctive characteristic of which is their fruit (legumen, seeds contained in pods). This botanical order is formed by three families: Mimosaceae, Caesalpiniaceae and Papilionaceae or Fabacea. The Papilionaceae family includes the most important allergenic species: Lens culinaris (lentil), Cicer arietinum (chick-pea), Pisum sátivum (pea), Arachis hipogea (peanut), Phaseolus vulgaris (bean) y Glycine max (soy). Legumes are an important ingredient in the Mediterranean diet. Among Spanish children, sensitivity to legumes is the fifth most prevalent food allergy. Lentil and chick-pea are the most frequent cause of allergic reactions to legumes in Spanish children. Legumes could be involved in severe allergic symptoms. The different legumes have structurally homologous proteins, but they are not all equally allergenic, thus making it difficult to distinguish in vitro and in vivo cross-reactivity. We have demonstrated by skin tests and CAP that most of the patients are sensitised to more than one species. We have demonstrated a great degree of cross-reactivity among lentil, chick-pea, pea and peanut by ELISA inhibition (> 50 % max. inhibition). Unlike the Anglo-Saxons population, this phenomenon implies clinical sensitisation for many Spanish children. The majority of our patients have had symptoms with more than one legume (median 3 legumes). Thirty-nine patients were challenged (open or simple blind) with two or more legumes and 32 (82 %) reacted to two or more legumes: 43,5 % to 3, 25,6 % to 2, 13 % to 4 legumes. Seventy three per cent of the patients challenged with lentil and pea had positive challenge to both, 69,4 % to lentil and chick-pea, 60 % to chick-pea and 64,3 % to lentil, chick-pea and pea simultaneously. Peanut allergy peanut can be associated to allergy to lentil, chick-pea and pea but less frequently. Contrarily, white bean and overall green bean and soy are well tolerated by children allergic to other legumes. In our study, 82 % of the children allergic to legumes had a sensitisation to pollen. Pea and bean are the legumes with more in vitro cross-reactivity with Lolium perenne, Olea europea and Betula alba. This cross-reactivity could be because of common antigenic determinants or due to the coexistence of pollen and legume allergy. Panallergens implication seems to be less probable. It is important to emphasize that in spite of an evident clinical and immunological cross-reactivity, the diagnosis of legume allergy should not be based only on specific IgE tests. The decision to eliminate one legume from the diet should be based on a positive oral food challenge.
Subject(s)
Cross Reactions , Fabaceae/immunology , Food Hypersensitivity/etiology , Adolescent , Allergens/adverse effects , Allergens/immunology , Child , Child, Preschool , Fabaceae/classification , Female , Food Hypersensitivity/diagnosis , Humans , Infant , Male , Plant Proteins/adverse effects , Plant Proteins/immunology , Pollen/adverse effects , Pollen/immunologyABSTRACT
BACKGROUND: Peanut allergy is common, potentially severe, and there has been a recent surge in clinical investigation of this important food allergen. OBJECTIVE: To provide the reader with a clinically oriented update on peanut allergy. DATA SOURCES: English language articles were selected from PubMed searches (search terms: peanut allergy, food allergy, anaphylaxis) and selected abstracts with a bias toward recent (3 years) studies judged to have immediate, practical clinical implications. RESULTS: Peanut allergy is an increasing problem in western diets that include this food. Both genetic and environmental factors influences the expression of this allergy. The at-risk subject is an atopic individual, with heightened risk for those with atopic dermatitis and/or other food allergies. The allergy is long-lived for most, may increase slightly in severity over time, but approximately 20% of young children will develop tolerance. Parameters that may identify the subset likely to achieve tolerance have been identified. Several large studies have determined laboratory parameters (skin tests, peanut-specific serum immunoglobulin E concentrations) with excellent predictive value (>95%) to diagnose current clinical reactivity or tolerance, although oral food challenges are necessary for a definitive diagnosis. Numerous practical lessons concerning management (avoidance, treatment, and prevention) have been identified. CONCLUSIONS: Recent studies provide the clinician with an armament of improved diagnostic and treatment modalities for peanut allergy. Studies are underway that are likely to provide more definitive therapies in the near future.
Subject(s)
Arachis/adverse effects , Food Hypersensitivity , Adolescent , Adult , Age of Onset , Allergens/adverse effects , Allergens/immunology , Anaphylaxis/etiology , Anaphylaxis/mortality , Animals , Arachis/immunology , Child , Child, Preschool , Cohort Studies , Cross Reactions , Cross-Sectional Studies , Diseases in Twins/epidemiology , Dose-Response Relationship, Immunologic , Environmental Exposure , Fabaceae/adverse effects , Fabaceae/immunology , Food Hypersensitivity/diagnosis , Food Hypersensitivity/epidemiology , Food Hypersensitivity/genetics , Food Hypersensitivity/immunology , Food Hypersensitivity/prevention & control , Food Hypersensitivity/therapy , Food Labeling , Humans , Immunoglobulin E/blood , Immunoglobulin E/immunology , Infant , Mice , Nuts/adverse effects , Nuts/immunology , Plant Oils/adverse effects , Plant Proteins/adverse effects , Plant Proteins/immunology , Predictive Value of Tests , Prevalence , Radioallergosorbent Test , Restaurants , Schools , Skin Tests , Twin Studies as TopicABSTRACT
As a consequence of the general increase in allergic sensitization, the prevalence of hypersensitivity reactions to multiple foods that share homologous proteins has become a significant clinical problem. A variety of these allergens conserved among plants (eg, profilin and lipid transfer proteins) and animals (eg, tropomyosin and caseins) have been characterized. Although studies with molecular biologic techniques have elucidated the nature of these ubiquitous allergens, clinical studies have lagged behind. The physician is called on to determine the risk of reaction to related foods among legumes, tree nuts, fish, shellfish, cereal grains, mammalian and avian food products, and a variety of other plant-derived foods that may share proteins with pollens, latex, and each other. Clinical evaluations require a careful history, laboratory evaluation, and in some cases oral food challenges. The pitfalls in the evaluation of food allergy-unreliable histories and limitations in laboratory assessment primarily caused by false-positive skin prick test responses/RAST results are magnified when dealing with cross-reactive proteins. This review focuses on the clinical data regarding cross-reacting food allergens with the goal of providing a background for improved risk assessment and a framework on which to approach these difficult clinical questions.
Subject(s)
Allergens/immunology , Food Hypersensitivity/immunology , Animals , Cross Reactions , Fabaceae/immunology , Fishes/immunology , Food Hypersensitivity/diagnosis , Food Hypersensitivity/therapy , Humans , Latex Hypersensitivity/immunology , Pollen/immunology , ShellfishABSTRACT
The ingestion of lupine seed flour (LSF) has been reported as a cause of allergic reactions, particularly in patients sensitized to peanut, but there is little evidence of its allergenic potential after inhalation. We sought to evaluate the clinical and immunologic reactivity to lupine in employees working with this seed flour. An occupational history was obtained in 7 subjects (median age, 35 years) working with LSF at an agricultural research center. Three subjects (1, 6, and 7) reported work-related allergy symptoms immediately after being exposed to lupine. Skin prick test results with LSF extract were positive in these 3 patients with work-related symptoms. Moreover, lupine-specific IgE antibodies were detected in subjects 6 and 7. In subject 6, the controlled exposure to LSF elicited immediate naso-ocular symptoms without changes in FEV(1). In subject 7, a bronchial provocation with LSF extract elicited an immediate fall (25%) in FEV(1). Double-blinded, placebo-controlled LSF oral challenge results were positive in subjects 6 and 7. Immunologic reactivity to other legumes was detected in subjects 6 and 7, but specific inhalation testing and oral challenge results were negative. Thus, the inhalation of lupine flour could be an important cause of allergic sensitization in exposed workers and might give rise to occupational asthma and food allergy.
Subject(s)
Fabaceae/immunology , Hypersensitivity, Immediate/etiology , Hypersensitivity/etiology , Immunoglobulin E , Medical Laboratory Personnel , Occupational Diseases/etiology , Plants, Medicinal , Adult , Crops, Agricultural/immunology , Double-Blind Method , Female , Humans , Hypersensitivity/immunology , Hypersensitivity, Immediate/immunology , Middle Aged , Occupational Diseases/immunology , Occupational Exposure , Seeds/immunologyABSTRACT
Development of vaccines against bovine pneumonia pasteurellosis, or shipping fever, has focused mainly on Mannheimia haemolytica A1 leukotoxin (Lkt). In this study, the feasibility of expressing Lkt in a forage plant for use as an edible vaccine was investigated. Derivatives of the M. haemolytica Lkt in which the hydrophobic transmembrane domains were removed were made. Lkt66 retained its immunogenicity and was capable of eliciting an antibody response in rabbits that recognized and neutralized authentic Lkt. Genes encoding a shorter Lkt derivative, Lkt50, fused to a modified green fluorescent protein (mGFP5), were constructed for plant transformation. Constructs were screened by Western immunoblot analysis for their ability to express the fusion protein after agroinfiltration in tobacco. The fusion construct pBlkt50-mgfp5, which employs the cauliflower mosaic virus 35S promoter for transcription, was selected and introduced into white clover by Agrobacterium tumefaciens-mediated transformation. Transgenic lines of white clover were recovered, and expression of Lkt50-GFP was monitored and confirmed by laser confocal microscopy and Western immunoblot analysis. Lkt50-GFP was found to be stable in clover tissue after drying of the plant material at room temperature for 4 days. An extract containing Lkt50-GFP from white clover was able to induce an immune response in rabbits (via injection), and rabbit antisera recognized and neutralized authentic Lkt. This is the first demonstration of the expression of an M. haemolytica antigen in plants and paves the way for the development of transgenic plants expressing M. haemolytica antigens as an edible vaccine against bovine pneumonic pasteurellosis.
Subject(s)
Bacterial Proteins , Bacterial Vaccines , Exotoxins/immunology , Fabaceae/metabolism , Hemolysin Proteins/immunology , Mannheimia haemolytica/immunology , Plants, Edible/immunology , Plants, Genetically Modified/immunology , Plants, Medicinal , Animals , Antibodies, Bacterial/blood , Cattle , Exotoxins/genetics , Exotoxins/metabolism , Fabaceae/genetics , Fabaceae/immunology , Green Fluorescent Proteins , Hemolysin Proteins/genetics , Hemolysin Proteins/metabolism , Immunization , Luminescent Proteins/genetics , Luminescent Proteins/metabolism , Mannheimia haemolytica/metabolism , Pasteurellosis, Pneumonic/microbiology , Pasteurellosis, Pneumonic/prevention & control , Plants, Edible/genetics , Plants, Edible/metabolism , Plants, Genetically Modified/genetics , Plants, Genetically Modified/metabolism , Rabbits , Recombinant Fusion Proteins/immunologySubject(s)
Allergens/immunology , Asthma/etiology , Fabaceae/immunology , Occupational Diseases/etiology , Plants, Medicinal , Rhinitis/etiology , Humans , Male , Middle AgedABSTRACT
BACKGROUND: Lentils seem to be the most common legume implicated in pediatric allergic patients in the Mediterranean area. However, no lentil allergen has been isolated and characterized. OBJECTIVE: We sought to purify and characterize relevant IgE-binding proteins from boiled lentil extracts. METHODS: IgE-binding proteins from crude and boiled lentil extracts were detected with a pool of sera from patients with lentil allergy. Allergens were isolated by gel-filtration chromatography followed by cation- and anion-exchange chromatography or by reverse-phase HPLC. Their characterization included N-terminal amino acid sequencing, complex asparagine-linked glycan detection, specific IgE immunodetection with 22 individual sera from allergic patients, and immunoblot and CAP inhibition assays. RESULTS: Heat treatment of lentils produced substantial changes in the SDS-PAGE patterns of whole extracts, mainly a strong increase of 12- to 16-kd bands and a decrease of 25- to 45-kd components. Major IgE-binding proteins from the boiled lentil extract were located in the 12- to 16-kd and 45- to 70-kd ranges. Two allergens of 16 kd, proteins L1 and L2, and another one of 12 kd, protein L3, were purified. N-terminal sequencing indicated that all 3 were related and allowed their identification as gamma-vicilin subunits. Protein L1 was recognized by 68% of the individual sera tested and inhibited 64% of the IgE binding by commercial lentil CAPs. A second type of allergen of 66 kd, named protein H, was also isolated and identified as a seed-specific biotinylated protein. Protein H reacted with 41% of the individual sera and produced 45% inhibition in CAP inhibition assays. CONCLUSIONS: Two different types of allergens have been identified in boiled lentils. Those of 12 to 16 kd, called Len c 1, correspond to gamma-vicilin subunits, and those of 66 kd, designated Len c 2, correspond to seed-specific biotinylated protein. Homology with proteins from other legume species can explain potential cross-reactions among these foods.
Subject(s)
Allergens/immunology , Fabaceae/immunology , Plant Proteins/immunology , Plants, Medicinal , Allergens/chemistry , Allergens/isolation & purification , Amino Acid Sequence , Child , Electrophoresis, Polyacrylamide Gel/methods , Heating , Humans , Immunoglobulin E/immunology , Molecular Sequence Data , Plant Extracts/analysis , Plant Extracts/chemistry , Plant Extracts/immunology , Plant Proteins/analysis , Seed Storage Proteins , Sequence Analysis, Protein/methodsABSTRACT
Legumes are an important source of proteins and their consumption is very frequent in the Mediterranean region and in some Asian and African countries. In some of these regions, lentils and chickpeas are one of the main food allergens. Legumes are also used as food additives due to their emulsifying properties and can be present in many manufactured foods. These hidden food allergens have the potential of causing adverse reactions in legume-sensitive subjects. The allergenic composition of various legumes has been investigated. They have been found to contain multiple allergens, a few of which have been cloned and sequenced. Legumes contain acid-resistant and thermostable allergens. There is a significant degree of cross-reactivity among legumes, the clinical relevance of which seems to be dependent on the dietary habits in different communities. In Spain, the consumption of several legumes is frequent and, therefore, clinical allergy to more than one species in children is common. Clinical manifestations include cutaneous, digestive and respiratory symptoms. Legumes can cause life-threatening reactions in sensitized individuals. Inhalation of steam, powder or flour from some legumes may cause respiratory diseases such as rhinitis, asthma and hypersensitivity pneumonitis. Soybean allergy is generally transitory, but clinical allergy to peanuts is rarely outgrown. The natural history of other legume allergies is less known and more studies are necessary to reach definite conclusions.
Subject(s)
Fabaceae/adverse effects , Fabaceae/immunology , Food Hypersensitivity/etiology , Plants, Medicinal , Allergens/administration & dosage , Allergens/immunology , Cross Reactions , Food Hypersensitivity/therapy , Humans , Occupational ExposureABSTRACT
UNLABELLED: Lupine flour (lupinus albus), recently authorized in France in human food, cross-reacts with peanuts. We report a case of acute asthma in a patient with allergy to peanuts. EXEGESIS: This patient has a severe allergy to peanuts, presenting as acute asthma. Skin prick-tests to raw and cooked lupine flour were positive. The level of specific-IgE (Allerbio, France) to lupine flour were high. Oral challenge test induced acute asthma at a dose of 965 mg of lupine flour. This quantity may be included in 100 g of bread. CONCLUSION: This case report points out the fact that lupine flour is a high-risk allergen in patients presenting allergy to peanuts. It is necessary to evaluate the allergenic risk of new foods before their introduction into human daily food intake and to establish a network of allergy vigilance.
Subject(s)
Arachis/adverse effects , Asthma/chemically induced , Fabaceae/adverse effects , Flour/adverse effects , Food Hypersensitivity/complications , Plants, Medicinal , Adolescent , Asthma/immunology , Fabaceae/immunology , Female , Food Hypersensitivity/immunology , Humans , Immunoglobulin E/blood , Skin TestsABSTRACT
The chick pea, Cicer arietinum, is a legume commonly consumed in Spain and other Mediterranean countries. The sera of 29 children (mean age: 8.4 years) with a current or past history of allergic reactions after ingestion of chick pea, and positive skin tests to this legume, were used to study the allergenic composition of raw and boiled chick pea extracts. The patient population was divided into 2 groups: group 1 consisted of 19 patients with clinical sensitivity confirmed by either positive oral challenges or a convincing recent history of anaphylaxis after eating chick peas, and group 2 consisted of 10 patients with clinical sensitivity in the past, but tolerant at the time of blood extraction. Six atopic children, not allergic to legumes, were included as controls. Specific IgE to the raw and boiled extracts was measured by ELISA. The allergenic composition of both extracts was analyzed by SDS-PAGE and immunoblots. There were no significant differences between specific IgE levels to the raw and boiled extracts (p = 0.23). The mean levels in group 1 were significantly higher than in group 2 and controls (p = 0.0001). Multiple IgE binding proteins/peptides were detected in both extracts in the molecular weight range of 10-106 kD. Only nontolerant patients recognized a similar number of bands in both extracts. Chick pea extracts contain a majority of heat-stable allergens, which could be responsible for the clinical sensitivity to chick pea. Patients with a current clinical allergy to chick pea have statistically higher specific IgE levels than tolerant patients and controls.
Subject(s)
Fabaceae/adverse effects , Fabaceae/immunology , Food Hypersensitivity/etiology , Immunoglobulin E/blood , Plants, Medicinal , Adolescent , Adult , Allergens/chemistry , Allergens/immunology , Child , Child, Preschool , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Female , Food Hypersensitivity/immunology , Hot Temperature , Humans , Immunoblotting , Male , Plant Extracts/chemistry , Plant Extracts/immunology , Skin TestsABSTRACT
Changes of dietary habits, new food technology, international meals and increasing consumption of exotic food has changed the repartition of food allergens. Some food allergens are worrisome and symptoms severe (peanut and nut butters). Others are new and increase strongly: exotic fruits, sesame, mustard and lupin. Primary prevention include avoidance of such food in high risk infants. Product labeling must be improved.