sodium-dodecyl-sulfate and Food-Hypersensitivity

No egg white products have been clearly proven to be hypoallergenic. The role of egg white proteins in allergic reactions to eggs is still debatable.. This study was designed to determine the importance of ovomucoid, an egg white protein, in the development of allergies to egg white.. We performed a double-blind, placebo-controlled food challenge in subjects with high levels of IgE antibodies for egg white to compare the allergenicities of heated and ovomucoid-depleted egg white, freeze-dried egg white, and heated egg white. Levels of IgE antibodies for egg white, ovomucoid, ovalbumin, ovotransferrin, and lysozyme were measured in serum by RAST.. Twenty-one of 38 subjects with positive challenge responses to freeze-dried egg white had negative challenge responses to heated egg white, whereas 16 of 17 subjects (94.1%) with positive responses to heated egg white did not respond to the heated and ovomucoid-depleted egg white challenge. The subjects with positive challenge responses to freeze-dried egg white tended to have higher IgE antibody values to ovomucoid than those with negative responses. IgE antibody levels to ovomucoid were significantly higher in subjects with positive responses to a challenge with heated egg white than in those with no response. There were no significant differences in the levels of IgE antibodies to the other proteins, except ovomucoid, in the negative-response and positive-response groups in challenge tests with freeze-dried and heated egg white.. The heated and ovomucoid-depleted egg white preparation was less allergenic than heated or freeze-dried preparations. Ovomucoid has a more important role in the pathogenesis of allergic reactions to egg white than other proteins in egg white.

Topics: Allergens; Antibodies, Anti-Idiotypic; Antibody Specificity; Child; Child, Preschool; Conalbumin; Double-Blind Method; Egg White; Electrophoresis, Polyacrylamide Gel; Female; Food Hypersensitivity; Hot Temperature; Humans; Infant; Male; Muramidase; Ovalbumin; Ovomucin; Placebos; Sodium Dodecyl Sulfate

At present, several in vitro tests for immunoglobulin E (IgE)-mediated food allergy are available. An estimation of the diagnostic accuracy of the various tests used in predicting clinical sensitivity to codfish in a well-characterized allergic material is necessary.. To compare the diagnostic value of four specific IgE tests, and histamine release from basophils (HR) in identifying clinical type I allergy to codfish. As a true diagnosis, double-blind, placebo-controlled food challenges (DBPCFC) were employed.. Eight clinically codfish-allergic adult patients were investigated together with 30 codfish-tolerant control subjects for evidence of codfish-specific reactivity by Phadebas RAST (PHA), Pharmacia CAP System RAST (CAP), Magic Lite (ML) and HR. To characterize the diagnostic properties of a freshly prepared raw codfish extract, experiments were conducted employing an in-house radioallergosorbent test (RAST), the Maxisorp RAST (MAXI) and HR. Finally, protein profile and IgE-reacting allergens were detected by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting.. The sensitivities of HR with commercial extract and the three commercially available specific IgE analyses were 0.83 and 1.00 respectively. Specificities were 1.00 (HR) and 0.87-1.00 (specific IgE tests). Freshly prepared codfish extracts improved the sensitivity of HR. SDS-PAGE revealed approximately 29 bands (< 14.3-200 kDa) including a band of 12-13 kDa, and in immunoblotting 18 sera identified 17 IgE-binding bands. The protein migrating at 12-13 kDa was identified in the fresh codfish extract tested with sera from all clinical codfish allergics, while no significant reaction was seen in the control subjects.. Based on the small number of adult patients included in our study, the in vitro assays with commercial and fresh extracts have high sensitivity and are acceptable for screening for codfish allergy. Specificity of Phadebas, CAP, and our in-house RAST was less than unity, whereas ML and strong binding of IgE to a 12-13 kDa protein completely matches DBPCFC results, and thus seems sufficient for establishing the diagnosis.

Topics: Adult; Animals; Double-Blind Method; Electrophoresis, Polyacrylamide Gel; Epitopes; Fishes; Food Hypersensitivity; Histamine Release; Humans; Immunoblotting; Immunoglobulin E; Skin Tests; Sodium Dodecyl Sulfate; Tissue Extracts

Patients allergic to garlic often present dermatitis, rhinitis, asthma, and urticaria after ingestion of garlic, contact with garlic, or exposure to garlic dust. Garlic-related anaphylaxis is rare, and the impact of heating on garlic allergens is not very clear. We report a case of anaphylaxis induced by ingestion of raw rather than cooked garlic with manifestations different from previous reports, and we hypothesized that heating could reduce the allergenicity of garlic. Serum total immunoglobulin E (IgE) and specific IgE were tested using the Phadia CAP System FEIA (Phadia, Uppsala, Sweden). Protein extracts from raw and cooked garlic were analyzed by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot. Serum-specific IgE for garlic was 8.16 kUA/L. IgE banding proteins could only be detected in raw garlic extract, because allergens in garlic were mostly degraded into small fragments after heating, as shown in SDS-PAGE profile. In conclusion, raw garlic could induce life-threatening anaphylaxis. However, most of its allergens are heat labile, and patients allergic to garlic might tolerate the cooked one well.

Topics: Adult; Allergens; Anaphylaxis; Blotting, Western; Cooking; Electrophoresis, Polyacrylamide Gel; Food Hypersensitivity; Garlic; Humans; Immunoglobulin E; Male; Sodium Dodecyl Sulfate

Prevention strategies in atopic dermatitis (AD) using allergen avoidance have not been consistently effective. New research reveals the importance of the skin barrier in the development of AD and possibly food allergy and asthma. Correcting skin barrier defects from birth may prevent AD onset or moderate disease severity.. We sought to determine the feasibility of skin barrier protection as a novel AD prevention strategy.. We enrolled 22 neonates at high risk for developing AD in a feasibility pilot study using emollient therapy from birth.. No intervention-related adverse events occurred in our cohort followed up for a mean time of 547 days. Of the 20 subjects who remained in the study, 3 (15.0%) developed AD, suggesting a protective effect when compared with historical controls. Skin barrier measurements remained within ranges seen in normal-appearing skin.. No conclusions regarding efficacy can be made without a control group.. Skin barrier repair from birth represents a novel and feasible approach to AD prevention. Further studies are warranted to determine the efficacy of this approach.

Topics: Asthma; Dermatitis, Atopic; Drug Combinations; Emollients; Feasibility Studies; Female; Follow-Up Studies; Food Hypersensitivity; Humans; Infant, Newborn; Male; Pilot Projects; Primary Prevention; Propylene Glycols; Prospective Studies; Risk Assessment; Skin Absorption; Sodium Dodecyl Sulfate; Treatment Outcome

Eggs are among the foods most frequently causing allergy. Hen eggs are the most important. Those of other birds are of lesser significance.. We report an unusual case of food allergy after consumption of eggs from duck and goose in an adult patient without hen egg allergy.. Skin prick tests were performed with fresh white and yolk from eggs of duck and goose and egg white, egg yolk, ovalbumin, and ovomucoid from hen egg. Specific serum IgE was measured to hen egg proteins. SDS-PAGE and IgE immunoblotting were carried out with egg white extracts from hen, duck, and goose.. Skin tests were positive to egg whites from duck and goose. The skin tests and specific serum IgE were negative to hen egg proteins. Immunoblotting demonstrated the presence of specific IgE to a proteic band of molecular weight around 45 kd.. We report a patient with an IgE-mediated allergy to egg white from duck and goose without hen egg allergy. Ovalbumin seems to be the responsible protein. The antigenic determinant of this protein seems to be specific of order Anseriforme and it is not present in the ovalbumin of order Galliforme.

Topics: Animals; Chickens; Ducks; Egg Proteins, Dietary; Eggs; Electrophoresis, Polyacrylamide Gel; Female; Food Hypersensitivity; Geese; Humans; Immunization; Immunoblotting; Immunoglobulin E; Middle Aged; Skin Tests; Sodium Dodecyl Sulfate

Topics: Adult; Anaphylaxis; Angioedema; Beer; Double-Blind Method; Electrophoresis, Polyacrylamide Gel; Female; Food Hypersensitivity; Humans; Male; Placebos; Pruritus; Sodium Dodecyl Sulfate

Two patients with tree nut allergy manifested by life-threatening systemic reactions reported the subsequent onset of systemic reactions after the consumption of coconut.. Herein, the IgE-binding proteins from coconut are described, and in vitro cross-reactivity with other nuts is investigated.. The IgE-binding profile of coconut endosperm tissue extract was analyzed by SDS-PAGE followed by immunoblotting. Immunoblot inhibition studies with walnut, almond, peanut, and coconut were performed.. Sera IgE from both patients recognized reduced coconut allergens with molecular weights of 35 and 36.5 kd. IgE from 1 patient also bound a 55-kd antigen. Preabsorption of sera with nut extracts suppressed IgE binding to coconut proteins. Preabsorption of sera with coconut caused the disappearance of IgE binding to protein bands at 35 and 36 kd on a reduced immunoblot of walnut protein extract in 1 patient and suppression of IgE binding to a protein at 36 kd in the other patient.. The reduced coconut protein at 35 kd was previously shown to be immunologically similar to soy glycinin (legumin group of seed storage proteins). The clinical reactivity in these 2 patients is likely due to cross-reacting IgE antibodies primarily directed against walnut, the original clinical allergy reported, and most likely to a walnut legumin-like protein. Coconut allergy in patients with tree nut allergy is rare; these are the first 2 patients ever reported, and therefore there is no general indication to advise patients with tree nut allergy to avoid coconut.

Topics: Adult; Allergens; Cocos; Cross Reactions; Electrophoresis, Polyacrylamide Gel; Fabaceae; Food Hypersensitivity; Humans; Hypersensitivity, Immediate; Immunoblotting; Male; Middle Aged; Nuts; Plant Proteins; Plants, Medicinal; Seeds; Sodium Dodecyl Sulfate

Topics: Child, Preschool; Electrophoresis, Polyacrylamide Gel; Fabaceae; Food Hypersensitivity; Humans; Hypersensitivity; Plant Extracts; Plants, Medicinal; Respiratory Hypersensitivity; Seeds; Skin Tests; Sodium Dodecyl Sulfate

Pollen-related food allergies to fresh fruit and vegetables are a well-known clinical phenomenon. Allergens related to Bet v 1 are responsible for these cross-reactions.. To characterize the allergen recognized by four carrot-allergic patients.. Sera from four patients showing strong immediate systemic reactions after contact or ingestion of raw carrot were studied by immunoblotting. The 18-kD allergen, named Dau c 1, was isolated by ethanol precipitation and specific extraction after SDS-PAGE and its N-terminal amino acid sequence was determined.. All the patients had significant levels of specific IgE to carrot, but no specific IgE to birch pollen was detected in any of them. IgE immunodetection with the sera only recognized a single band of around 18 kD in raw carrot and in celery (with weaker reaction). No reactive band was found with birch pollen. These results were confirmed using a polyclonal anti-carrot antiserum. The carrot IgE-binding protein had a pl of 4.2 and its N-terminal sequence was homologous to that of Bet v 1 and to allergens previously described in celery and other foods. The four patients studied were not sensitized to birch pollen and three of them tolerated fruit ingestion.. The whole study indicated that a sensitization to Dau c 1 induces IgE antibodies that do not cross-react with birch pollen allergens.

Topics: Adult; Allergens; Antigens, Plant; Cross Reactions; Daucus carota; Electrophoresis, Polyacrylamide Gel; Female; Food Hypersensitivity; Humans; Immunoblotting; Plant Proteins; Sodium Dodecyl Sulfate

Allergy to apple is commonly associated with birch pollinosis because the two share homologous allergens. However, some patients have apple allergy but no birch pollinosis, suggesting that there are allergens that do not cross-react with birch.. The aim of the study was to evaluate the IgE reactivity pattern to an apple extract in subjects with allergic reactions to apple, with and without birch hay fever.. Forty-three patients with oral allergy syndrome for apple and positive open food challenge, skin prick test, and serum specific IgE antibodies to apple were admitted to the study. Thirty-two had birch pollinosis (documented by specific IgE for birch) and 11 were not allergic to birch. The IgE reactivity pattern to apple extract was identified by SDS-PAGE and immunoblotting. The consistent allergen, a 9-kd protein, was then purified by HPLC and characterized by periodic acid-Schiff staining, isoelectric point, and N-terminal amino acid sequencing.. The sera from 28% of patients allergic to apple with birch pollinosis, but from all patients allergic only to apple, recognized the 9-kd protein. This protein has an isoelectric point of 7.5 and is not glycosylated. Determination of its partial amino acid sequence showed that it belongs to the family of lipid transfer proteins, which act as major allergens in Prunoideae fruits.. These results indicate that a lipid transfer protein is an important allergen in patients allergic to apple but not to birch pollen. The prevalent IgE reactivity to this allergen in subjects with no birch pollinosis and the physicochemical characteristics of this protein suggest that sensitization may occur through the oral route.

Topics: Adolescent; Adult; Allergens; Amino Acid Sequence; Antigens, Plant; Carrier Proteins; Chromatography, Gel; Chromatography, High Pressure Liquid; Chromatography, Ion Exchange; Electrophoresis, Polyacrylamide Gel; Female; Food Hypersensitivity; Humans; Immunoblotting; Isoelectric Focusing; Male; Middle Aged; Molecular Sequence Data; Periodic Acid-Schiff Reaction; Plant Proteins; Rosales; Sodium Dodecyl Sulfate; Staining and Labeling

The present investigation was undertaken to obtain molecular data of a new immunoglobulin (Ig)E-binding birch pollen protein with a mass of 35 kDa. In a previous study, this protein showed IgE cross-reactivity with 34- and 35-kDa proteins in apples, pears, carrots, bananas and other exotic fruits. Since the protein was N-terminally blocked, it was purified by preparative SDS-PAGE, and multiple proteolytic fragments were subsequently generated by in-gel digestion with the endoproteinases Glu C, Lys C and Clostripain. After electrophoretic separation and blotting onto polyvinylidene difluoride (PVDF), the resulting polypeptides were subjected to N-terminal amino acid microsequencing. The internal sequences obtained showed a high degree of sequence identity to isoflavone reductases (IFR) and isoflavone reductase-like proteins (IRL) from several plants which also had a similar size. For a stretch of 25 consecutive residues this identity ranged from 56% for IFR from peas and chick peas and an IRL from maize, to 80% for a tobacco IRL. A 453 bp fragment was amplified from total birch pollen RNA by polymerase chain reaction (PCR) using primers derived from the nucleotide sequence of the tobacco IRL. The deduced 151 amino acid sequence represented approximately 50% of the protein and confirmed the sequence identities obtained by Edman degradation. Moreover, the 25 amino acid sequence was included in the cloned fragment. Deduced and determined amino acids showed only one mismatch, which was due to a single nucleotide exchange. At the antibody level, the immunological relationship of the birch pollen protein to IRL and IFR was demonstrated by immunoblotting with a rabbit antiserum against a pea IFR which recognized the same birch protein as patients' IgE. The rabbit antiserum also reproduced the cross-reactivity pattern previously observed with patients' IgE by recognizing related proteins in specific plant foods, including some exotic fruits. We therefore suggest that the 35-kDa birch pollen protein belongs to the IFR/IRL family and represents a minor allergen, possibly being responsible for less common pollen-related food allergies in patients allergic to birch pollen.

Topics: Allergens; Amino Acid Sequence; Amino Acids; Animals; Antigens, Differentiation; Base Sequence; Cloning, Molecular; Cross Reactions; DNA; Electrophoresis, Polyacrylamide Gel; Food; Food Hypersensitivity; Galectin 3; Glycosylation; Humans; Immunoblotting; Molecular Sequence Data; Plant Proteins; Plants; Pollen; Polymerase Chain Reaction; Rabbits; Sodium Dodecyl Sulfate; Trees

Several egg white and egg yolk and avian proteins have been described as a cause of inhalant allergy. Sometimes inhalational type I hypersensitivity to these proteins is associated with food allergy to egg.. We studied two patients who experienced respiratory and food allergic symptoms upon exposure to egg or avian antigens through the inhalative or digestive routes. Clinical and immunological studies were carried out in order to identify individual allergens from these sources that could be responsible for crossreactivity reactions.. Patient 1 showed IgE sensitization to egg yolk livetins, feathers, and chicken serum. Specific bronchial challenge with chicken albumin and livetin extracts elicited a positive early asthmatic response and an increase in serum eosinophil cationic protein. Immunoblot and CAP-inhibition studies in this patient supported that chicken albumin (alpha-livetin) was the crossreactive antigen present in egg yolk and chicken serum and feathers. Patient 2 showed sensitization to egg white, ovomucoid and lysozyme. However, SDS-PAGE and immunoblot studies demonstrated contaminating lysozyme in the ovomucoid extract and identified lysozyme as the main allergen causing egg sensitization in this patient. Conjunctival challenge test confirmed allergy to lysozyme.. Egg yolk and egg white proteins may act not only as ingested allergens but also as aeroallergens. Immunological studies using highly purified preparations of egg proteins are useful for the accurate diagnosis of allergic reactions to egg proteins and to identify individual allergens that may be responsible for crossreactivity reactions.

Topics: Adult; Allergens; Antibodies; Asthma; Bronchial Provocation Tests; Conjunctiva; Conjunctivitis, Allergic; Egg Proteins; Electrophoresis, Polyacrylamide Gel; Female; Food Hypersensitivity; Histamine Release; Humans; Immunoblotting; Immunoglobulin E; Respiratory Hypersensitivity; Rhinitis, Allergic, Seasonal; Skin Tests; Sodium Dodecyl Sulfate

Little is known about the role of bell peppers in food allergy. We collected sera from 11 patients with food allergy to bell peppers to analyze bell pepper extracts for allergen composition.. Proteins of mature fruits of eight horticultural strains of bell peppers were extracted and tested with patients' sera for IgE binding and with monoclonal and polyclonal antibodies in immunoblot.. Profilin was detected in bell pepper extracts by an anti-celery profilin antibody. It showed high IgE binding activity in all extracts, which could be inhibited by recombinant birch pollen profilin. Anti-birch pollen monoclonal antibody BIP3, directed against birch pollen proteins between 30 and 69 kD, bound to bell pepper antigens of comparable molecular weights. A homologue of the major birch pollen allergen Bet v 1 was detected in four of eight horticultural strains of bell peppers, and was shown to bind IgE in 1 of the 11 patients. A 23-kD allergen of bell peppers was shown to correspond to the 23-kD major paprika allergen by IgE absorption experiments. Its N-terminal sequence showed 100% identity to P23 from tomatoes.. The appearance of profilin in all and Bet v 1 in 50% of the tested horticultural strains indicates that bell peppers have to be considered potentially dangerous for Bet v 1- and profilin-sensitized patients. Moreover, in 4 of 8 horticultural strains of bell peppers a homologue of the osmotin-like protein P23 from tomatoes is responsible for substantial IgE binding. Contact with Bet v 1 and P23 homologues in bell peppers can therefore be minimized by avoidance of the respective horticultural strains.

Topics: Adult; Allergens; Amino Acid Sequence; Capsicum; Contractile Proteins; Cross Reactions; Electrophoresis, Polyacrylamide Gel; Female; Food Hypersensitivity; Humans; Immunoblotting; Immunoglobulin E; Male; Microfilament Proteins; Middle Aged; Molecular Sequence Data; Plant Extracts; Plant Proteins; Plants, Medicinal; Pollen; Profilins; Sodium Dodecyl Sulfate

We studied the binding activities of IgE, IgG and IgA antibodies in patients with allergy to hen's egg white against two different ovalbumin (OVA) preparations, which were physically or chemically denatured OVA and enzyme-digested OVA fragments. The binding activities of IgE antibodies to these OVA preparations with those of IgG or IgA antibodies were compared. It was found that the binding activities of IgE antibodies to denatured OVA by treatment with dithiothreitol, urea or hydrochloric acid were similar to those of IgG or IgA antibodies. In contrast, the binding activities of IgE antibodies to heat-denatured OVA or by treatment with sodium hydroxide at pH 11.0 were different from those of IgG or IgA antibodies to these denatured OVA. Furthermore, we found that the binding activities of anti-OVA antibodies in sera from patients with allergy to hen's egg white against fragmented OVA were different between IgE antibodies and IgG or IgA antibodies. Thus, it can be concluded that IgE antibodies to OVA in sera from patients with allergy to egg white differ from IgG or IgA antibodies in respect to binding activities against different preparations of denatured or fragmented OVA, probably due to differences in fine specificities of these antibodies against OVA.

Topics: Allergens; Antibodies; Antibodies, Anti-Idiotypic; Antibody Specificity; Binding Sites, Antibody; Child; Child, Preschool; Egg White; Electrophoresis, Polyacrylamide Gel; Epitopes; Female; Food Hypersensitivity; Humans; Immunoglobulin A; Immunoglobulin E; Immunoglobulin G; Infant; Male; Ovalbumin; Peptide Fragments; Protein Denaturation; Sodium Dodecyl Sulfate

Cross-reactive allergens may be responsible for the clustering of food allergies seen in patients hypersensitive to fruits and vegetables. The pooled sera of six individuals were used to investigate cross-antigenicity among freshly prepared extracts of celery (Cy), cucumber (Cc), carrot (Ct), and watermelon (W). Each patient demonstrated clinical allergy to one or more study foods and, with the exception of Ct in two cases, had IgE to all four extracts by skin test or ELISA. In comparisons of each food against itself and the other three antigens, ELISA inhibition assays demonstrated allergenic similarity among Cy, Cc, Ct, and W by their similar slopes and 50% inhibition concentrations (2.0-7.3 micrograms/mL). In contrast, mountain cedar pollen (MC) produced at 50% inhibition of each food which was 10-fold higher (26.9-70.8 micrograms/mL) and had a flatter slope. Immunoblots of individual sera showed a 15-kD protein band common to all four foods. Pooled sera immunoblot inhibitions (100 and 5 micrograms/mL) demonstrated mutual inhibition of all bands in each of the four foods with the exception of a 28-kD protein of W uniquely inhibited by itself. We conclude that Cy, Cc, Ct, and W possess shared antigens that may account for clustering of these food allergies in patients.

Topics: Adult; Aged; Allergens; Antibody Affinity; Cross Reactions; Electrophoresis, Polyacrylamide Gel; Enzyme-Linked Immunosorbent Assay; Female; Food Hypersensitivity; Fruit; Humans; Immunoblotting; Immunoglobulin E; Male; Middle Aged; Sodium Dodecyl Sulfate; Vegetables

Peanuts are frequently a cause of food hypersensitivity reactions in children. Serum from nine patients with atopic dermatitis and a positive double-blind, placebo-controlled, food challenge to peanut were used in the process of identification and purification of the peanut allergens. Identification of a second major peanut allergen was accomplished with use of various biochemical and molecular techniques. Anion exchange chromatography of the crude peanut extract produced several fractions that bound IgE from the serum of the patient pool with positive challenges. By measuring antipeanut specific IgE and by IgE-specific immunoblotting we have identified an allergic component that has two closely migrating bands with a mean molecular weight of 17 kd. Two-dimensional gel electrophoresis of this fraction revealed it to have a mean isoelectric point of 5.2. According to allergen nomenclature of the IUIS Subcommittee for Allergen Nomenclature this allergen is designated, Ara h II (Arachis hypogaea).

Topics: 2S Albumins, Plant; Allergens; Amino Acid Sequence; Amino Acids; Antigens, Plant; Arachis; Child; Child, Preschool; Chromatography, Ion Exchange; Dermatitis, Atopic; Electrophoresis, Polyacrylamide Gel; Enzyme-Linked Immunosorbent Assay; Food Hypersensitivity; Glycoproteins; Humans; Immunoblotting; Infant; Molecular Sequence Data; Plant Proteins; Sodium Dodecyl Sulfate

Topics: Amino Acids; Animals; Carbohydrates; Child; Child, Preschool; Dietary Fats; Double-Blind Method; Electrophoresis, Polyacrylamide Gel; Enzyme-Linked Immunosorbent Assay; Food Hypersensitivity; Food, Formulated; Humans; Immunoblotting; Infant; Infant Food; Milk; Milk Hypersensitivity; Placebos; Safety; Skin Tests; Sodium Dodecyl Sulfate

The IgE response to coriander and other spices was studied by immunoblotting, after separation of the spice extracts by isoelectric focusing and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). A major IgE-binding component from coriander had an isoelectric point of pH5. After incubation of SDS-PAGE-separated spice extracts with serum from a patient with an occupational allergy to spices, a closely related pattern of IgE binding to coriander, dill and anise extract was observed. These results suggest that the botanically related spices, coriander, anise and dill, contain common IgE-binding structures.

Topics: Antigens; Collodion; Condiments; Electrophoresis, Polyacrylamide Gel; Food Hypersensitivity; Humans; Immunoglobulin E; Isoelectric Focusing; Sodium Dodecyl Sulfate

Allergy to potato is uncommon, and even more uncommon is allergy to potato pollen. The occurrence of both phenomena in the same patient made it possible to study cross-reactivity patterns of potato antigens. An 11-year-old girl, exclusively breast-fed for her first 4 months, developed anaphylactic symptoms after ingestion of potato at 5 months of age when she was fed potato for the first time. Subsequently, she developed urticaria, angioedema, and respiratory and systemic symptoms on contact with potatoes, ingestion of potatoes, and exposure to cooking potatoes or potato pollen. Three allergenic extracts from potato pulp, peel, and pollen were prepared. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate and isoelectrofocusing of the three extracts were performed. IgE-mediated allergy to these extracts was demonstrated by means of immediate skin test reactivity, positive passive transfer, RAST, RAST inhibition, and leukocyte histamine release. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the pulp extract followed by electroblotting and autoradiography demonstrated specific IgE antibodies directed against several proteins ranging from 14,000 to 40,000 daltons.

Topics: Child; Cross Reactions; Electrophoresis, Polyacrylamide Gel; Female; Food Hypersensitivity; Humans; Immunoglobulin E; Intradermal Tests; Plant Proteins; Pollen; Radioallergosorbent Test; Skin Tests; Sodium Dodecyl Sulfate; Vegetables

Crude peanut protein fractions from raw and roasted peanuts were examined in the RAST with 10 sera from patients showing clinical peanut sensitivity. The radioactive uptake results, which were generally high, did not reveal any distinguishable pattern. Two commercially available peanut proteins, peanut lectin and phospholipase D, gave poor RAST responses. Three purified peanut proteins, alpha-arachin, conarachin I, and concanavalin A-reactive glycoprotein, all gave significant RAST results that were generally lower than those obtained with the crude extracts. The extent of RAST inhibition obtained with these materials was inversely related to their abundance in the total peanut protein. Crossed immunoelectrophoresis with extracts from raw and roasted peanut indicated the presence of 22 and 10 anodically migrating antigens, respectively. Sixteen IgE binding antigens were revealed for raw peanut and seven for roasted peanut after incubation with a mixed serum from the 10 patients in crossed radioimmunoelectrophoresis (CRIE) using 125I-labeled anti-IgE. CRIE plates treated with individual serum samples showed that all the patients had specific IgE for the major antigen peak, which has been tentatively identified as alpha-arachin. This major storage protein of peanut, which is known to be particularly heat resistant; may be of greater clinical significance than its apparently low RAST activity would seem to indicate.

Topics: Adolescent; Adult; Allergens; Antigens, Plant; Arachis; Child; Child, Preschool; Concanavalin A; Counterimmunoelectrophoresis; Electrophoresis, Polyacrylamide Gel; Female; Food Hypersensitivity; Glycoproteins; Humans; Immunoglobulin E; Lectins; Male; Phospholipase D; Plant Lectins; Plant Proteins; Radioallergosorbent Test; Sodium Dodecyl Sulfate