Computationally predicted IgE epitopes of walnut allergens contribute to cross-reactivity with peanuts.

BACKGROUND: Cross-reactivity between peanuts and tree nuts implies that similar immunoglobulin E (IgE) epitopes are present in their proteins. OBJECTIVE: To determine whether walnut sequences similar to known peanut IgE-binding sequences, according to the property distance (PD) scale implemented in the Structural Database of Allergenic Proteins, react with IgE from sera of patients with allergy to walnut and/or peanut. METHODS: Patient sera were characterized by western blotting for IgE binding to nut protein extracts and to peptides from walnut and peanut allergens, similar to known peanut epitopes as defined by low PD values, synthesized on membranes. Competitive enzyme-linked immunosorbent assay (ELISA) was used to show that peanut and predicted walnut epitope sequences compete with purified Ara h 2 for binding to IgE in serum from a cross-reactive patient. RESULTS: Sequences from the vicilin walnut allergen Jug r 2, which had low PD values to epitopes of the peanut allergen Ara h 2, a 2S albumin, bound to IgE in sera from five patients who reacted to either walnut or peanut or both. A walnut epitope recognized by sera from six patients mapped to a surface-exposed region on a model of the N-terminal pro-region of Jug r 2. This predicted walnut epitope competed for IgE binding to Ara h 2 in serum as well as the known IgE epitope from Ara h 2. CONCLUSIONS: Sequences with low PD value (< 8.5) to known IgE epitopes could contribute to cross-reactivity between allergens. This further validates the PD scoring method for predicting cross-reactive epitopes in allergens.

Utilidad y complicaciones de la biopsia percutánea esplénica con aguja tru-cut guiada por imágenes / Ultrasound guided needle biopsy of the spleen: review of 13 procedures

Background: Needle biopsies of the spleen were avoided due to the fear of bleeding in a highly vascularized organ. However their safety, even using 18 gauge needles, has been demonstrated. Aim: To report the experience with ultrasound guided needle biopsies of the spleen. Material and Methods: Retrospective review of records of ultrasound guided biopsies of the spleen using Tru-cutTM needles, performed between 2005 and 2009. Results: Thirteen procedures performed in 12 patients were identified. A specific diagnosis was achieved in nine (69 percent) procedures (lymphoma in four, melanoma in 2, sarcoma in 1, extremedullary erythropoiesis in one and splenic cryptococcosis in one. Two patients with negative results were subjected to a new biopsy, which yielded the diagnosis of lymphoma. A third patient was studied elsewhere, finding a malignant tumor. Two patients had complications, one had a vagal reaction and other had a perisplenic hematoma without clinical repercussion. Conclusions: Ultrasound guided needle biopsy of the spleen is a safe and useful procedure.

Objetivo: Reportar la experiencia de biopsias percutáneas esplénicas con aguja tru-cut guiadas por imágenes. Materiales y Métodos: Revisión retrospectiva de biopsias esplénicas con aguja tru-cut guiadas por ultrasonido (US) y tomografía computada (TC) realizadas en nuestro hospital desde Enero de 2005 a Abril de 2009. Resultados: Se identificaron un total de 13 procedimientos. La biopsia percutánea logró un diagnóstico específico en 9 (69 por ciento) de las 13 intervenciones. Los diagnósticos fueron linfoma (n = 4), melanoma (n = 2), sarcoma (n = 1), hematopoyesis extramedular (n = 1) y criptococosis esplénica (n = 1). De las biopsias no diagnósticas 3 casos correspondieron a patología neoplásica y uno a patología benigna. Se reportaron 2 complicaciones (15 por ciento). Discusión: La biopsia esplénica percutánea guiada por imágenes con aguja tru-cut es un procedimiento útil y seguro, capaz de determinar el diagnóstico definitivo en la mayoría de los pacientes y evitar la mayoría de las esplenectomías diagnósticas.

Rol de la tomografía computada de abdomen en la evaluación de gastrectomía en manga laparoscópica y sus complicaciones / Role of abdominal computed tomography in the evaluation of laparoscopic sleeve gastrectomy technique and its complications

Bariatric surgery has developed considerably over recent years due to the progressive increase in obesity worldwide. The laparoscopic sleeve gastrectomy is a new restrictive technique, with promising initial outcomes. CT images play an important role in postoperative evaluation as well as in complication management in patients undergoing this surgical technique. Here we review the role of abdominal computed tomography in the study of potential complications.

La cirugía bariátrica se ha desarrollado considerablemente en el último tiempo como consecuencia del aumento progresivo de la obesidad a nivel mundial. La gastrectomía en manga laparoscópica es una técnica restrictiva nueva, con resultados iniciales prometedores. Las imágenes juegan un rol importante en la evaluación postoperatoria por lo que es imprescindible conocer los cambios anatómicos normales y las principales complicaciones de esta técnica. En este trabajo revisamos el rol de la tomografía computada de abdomen en el estudio de posibles complicaciones.

Pistachio vicilin, Pis v 3, is immunoglobulin E-reactive and cross-reacts with the homologous cashew allergen, Ana o 1.

BACKGROUND: Patients allergic to cashew nuts often report allergy to pistachio, which could be a result of cross-reactivity between the two as both are members of the Anacardiaceae family. OBJECTIVE: Because cashew 7S globulin (vicilin, Ana o 1) is a recognized major allergen, we cloned the pistachio homologue and assayed it for IgE reactivity and cross-reactivity with Ana o 1. METHODS: Degenerate primers for 7S globulin were used in PCR to amplify DNA from a pistachio cDNA library. An isolate was sequenced, cloned and expressed in Escherichia coli. Reactivity to the allergen was screened by dot blot using 19 pistachio and/or cashew-allergic patients' sera. Cross-reactivity was investigated by inhibition dot- and Western immunoblot assays using pistachio/cashew-allergic patients' sera, and monoclonal antibodies (MAbs) raised against recombinant Ana o 1 (rAna o 1). RESULTS: An isolate was found that coded for a 7S vicilin-like protein, designated Pis v 3. IgE reactivity to Pis v 3 was found in the serum of seven of the 19 (37%) patients with histories of allergy to both pistachio and cashew or who were allergic to cashew but had never eaten pistachio. The seven patients with IgE that recognized rPis v 3 also recognized rAna o 1. Six of nine anti-rAna o 1 MAbs also showed reactivity to rPis v 3 on dot blots. CONCLUSION: Of the 37% of pistachio/cashew-allergic patients' sera that recognized the pistachio allergen, rPis v 3, all showed complete cross-reactivity with rAna o 1. The data does not identify the primary sensitizing agent but suggests that IgE reactivity to rPis v 3 and rAna o 1 is focused on the most conserved regions of the proteins. Clinical histories suggest that in some cases, cashew was the sensitizing agent. rPis v 3 is a likely contributor to the observed co-sensitivity to pistachio and cashew in some patients.

Ses i 6, the sesame 11S globulin, can activate basophils and shows cross-reactivity with walnut in vitro.

BACKGROUND: Sesame allergy is increasingly being reported, and multi-sensitization to peanut and tree nuts has been described. The clinical relevance and cross-reactivity of many sesame proteins, such as Ses i 6, are unknown. OBJECTIVE: The aims of this study were to perform a preliminary examination of the cross-reactivity of Ses i 6 in vitro, examine the ability of Ses i 6 to activate basophils in a modified basophil activation test (mBAT), and assess whether such an assay may help to distinguish between potentially relevant and irrelevant IgE reactivity towards 11S globulin proteins. METHODS: Inhibition immunoblotting and chicken anti-rJug r 4 antibodies were used to determine the cross-reactivity of rSes i 6. Basophils from atopic donors were stripped of resident IgE before passive sensitization with food-allergic sera and challenged with protein extracts or recombinant protein. Basophil activation was measured using two activation markers, CD203c and CD63, via flow cytometry. RESULTS: IgE immunoblotting showed cross-reactivity between rJug r 4 and rSes i 6 using sera from two human donors and chicken IgY. Additionally, rSes i 6 activated basophils passively sensitized with sesame-allergic sera. Cross-reactive serum from a sesame-allergic but walnut-tolerant donor was not able to activate basophils when challenged by walnut extract despite IgE reactivity to walnut determined by immunoblotting. CONCLUSIONS: The sesame 11S globulin shows partial immunological cross-reactivity with walnut, and although it is classified as a minor allergen, activated basophils sensitized with serum from seven out of eleven sesame-allergic donors. Additionally, the mBAT may help distinguish between clinically relevant and irrelevant in vitro IgE cross-reactivity of seed storage proteins in nuts and seeds and thus warrants use in further studies.

Allergen immunotherapy with heat-killed Listeria monocytogenes alleviates peanut and food-induced anaphylaxis in dogs.

BACKGROUND: Heat-killed Listeria monocytogenes (HKL) potently stimulates interferon (IFN)-gamma production in CD4 T-lymphocytes, and when used as adjuvant for immunotherapy, reduces immunoglobulin (Ig)E production and reverses established allergen-induced airway hyperreactivity (AHR) in a murine model of asthma. We asked if such treatment could decrease established peanut-induced anaphylaxis or cow's milk-induced food allergy in highly food-allergic dogs. METHODS: We therefore studied four 4-year-old atopic colony dogs extremely allergic to peanut (Group I), as well as five 7-year-old dogs very allergic to wheat, milk and other foods (Group II). All dogs experienced marked allergic symptoms, including vomiting and diarrhea on oral challenge with the relevant foods. The dogs were then vaccinated once subcutaneously with peanut or milk and wheat with HKL emulsified in incomplete Freund's adjuvant. RESULTS: Following vaccination of the allergic dogs with HKL and allergen, oral challenges with peanut (Group I) or milk (Group II) elicited only minor or no symptoms. In addition, skin test end-point titrations showed marked reductions for >10 weeks after treatment, and levels of Ara h 1-specific IgE in serum of peanut sensitive dogs, as demonstrated by immunoblotting, were greatly reduced by treatment with HKL plus peanut allergen. CONCLUSIONS: Thus, HKL plus allergen treatment markedly improved established food allergic responses in dogs, suggesting that such an immunotherapy strategy in humans might greatly improve individuals with food allergy and anaphylaxis.

Extensive in vitro cross-reactivity to seed storage proteins is present among walnut (Juglans) cultivars and species.

BACKGROUND: Tree nuts, including English walnuts (Juglans regia), are sources of food allergens often associated with life-threatening allergic reactions. It is unknown if seed storage proteins from other Juglans species have IgE epitopes similar to those of the important English walnut allergens, Jug r 1 (2S albumin) and Jug r 2 (vicilin-like). OBJECTIVE: To screen for potential germplasm sources of hypoallergenic seed storage proteins of relevance in walnut food allergy. We sought to identify English walnut cultivars (cvs) or other Juglans species that showed decreased IgE binding to major seed storage proteins or an inability to cross-react with Jug r 1 or Jug r 2. METHODS: We determined if IgE in sera of patients who have had life-threatening systemic reactions to English walnut bound protein extracts from all tested walnut cvs (57 cvs total) or species (six) by Western immunoblot. Further, we used immunoblot inhibition to determine the in vitro cross-reactivity of Jug r 1 and Jug r 2, native and recombinant, with several walnut species. RESULTS: All walnut cvs and species contain allergenic proteins. Furthermore, as shown by in vitro immunoblot inhibition, the major walnut allergens in the species tested cross-reacted with those in J. regia cv. Chandler and J. nigra cv. Thomas extracts. CONCLUSIONS: Based on our findings, it is unlikely that a composite hypoallergenic walnut could be bred from available germplasm. In addition, patients with severe allergy to English walnut are likely to be clinically allergic to all commercial English walnut cvs and other closely related Juglans species.

Effects of roasting, blanching, autoclaving, and microwave heating on antigenicity of almond (Prunus dulcis L.) proteins.

Whole, unprocessed Nonpareil almonds were subjected to a variety of heat processing methods that included roasting (280, 300, and 320 degrees F for 20 and 30 min each; and 335 and 350 degrees F for 8, 10, and 12 min each), autoclaving (121 degrees C, 15 psi, for 5, 10, 15, 20, 25, and 30 min), blanching (100 degrees C for 1, 2, 3, 4, 5, and 10 min), and microwave heating (1, 2, and 3 min). Proteins were extracted from defatted almond flour in borate saline buffer, and immunoreactivity of the soluble proteins (normalized to 1 mg protein/mL for all samples) was determined using enzyme linked immunosorbent assay (ELISA). Antigenic stability of the almond major protein (amandin) in the heat-processed samples was determined by competitive inhibition ELISA using rabbit polyclonal antibodies raised against amandin. Processed samples were also assessed for heat stability of total antigenic proteins by sandwich ELISA using goat and rabbit polyclonal antibodies raised against unprocessed Nonpareil almond total protein extract. ELISA assays and Western blotting experiments that used both rabbit polyclonal antibodies and human IgE from pooled sera indicated antigenic stability of almond proteins when compared with that of the unprocessed counterpart.

Walnut polyphenolics inhibit in vitro human plasma and LDL oxidation.

Recent epidemiologic studies have associated nut consumption with a reduced incidence of cardiovascular mortality. However, little is known about the contribution of nut polyphenols to antioxidant and cardiovascular protection. In this investigation, polyphenol-rich extracts from English walnuts (Juglans regia) were studied and compared with ellagic acid for their ability to inhibit in vitro plasma and LDL oxidation, as well as their effects on LDL alpha-tocopherol during oxidative stress. In addition, the Trolox equivalent antioxidant activity (TEAC) was determined and liquid chromatography electrospray detection mass spectrometry (LC-ELSD/MS) analyses of the walnut extracts were performed. 2,2'-Azobis'(2-amidino propane) hydrochloride (AAPH)-induced LDL oxidation was significantly inhibited by 87 and 38% with the highest concentration (1.0 micromol/L) of ellagic acid and walnut extract, respectively. In addition, copper-mediated LDL oxidation was inhibited by 14 and 84% in the presence of ellagic acid and walnut extract, respectively, with a modest, significant LDL alpha-tocopherol sparing effect observed. Plasma thiobarbituric acid reacting substance (TBARS) formation was significantly inhibited by walnut extracts and ellagic acid in a dose-dependent manner, and the extracts exhibited a TEAC value greater than that of alpha-tocopherol. LC-ELSD/MS analysis of the walnut extracts identified ellagic acid monomers, polymeric ellagitannins and other phenolics, principally nonflavonoid compounds. These results demonstrate that walnut polyphenolics are effective inhibitors of in vitro plasma and LDL oxidation. The polyphenolic content of walnuts should be considered when evaluating their antiatherogenic potential.

Detection and stability of the major almond allergen in foods.

Almond major protein (AMP or amandin), the primary storage protein in almonds, is the major allergen recognized by almond-allergic patients. A rabbit antibody-based inhibition ELISA assay for detecting and quantifying AMP in commercial foods has been developed, and this assay, in conjunction with Western blotting analyses, has been applied to the investigation of the antigenic stability of AMP to harsh food-processing conditions. The ELISA assay detects purified AMP at levels as low as 87 +/-16 ng/mL and can detect almond at between 5 and 37 ppm in the tested foods. The assay was used to quantify AMP in aqueous extracts of various foods that were defatted and spiked with known amounts of purified AMP or almond flour. In addition, AMP was quantified in commercially prepared and processed almond-containing foods. Neither blanching, roasting, nor autoclaving of almonds markedly decreased the detectability of AMP in subsequent aqueous extracts of almonds. Western blots using both rabbit antisera and sera from human almond-allergic patients confirm a general stability of the various peptides that comprise this complex molecule and show that the rabbit antibody-based assay recognizes substantially the same set of peptides as does the IgE in sera from almond-allergic patients.

Electrophoretic and immunological analyses of almond (Prunusdulcis l.) genotypes and hybrids.

Aqueous extracts from sixty almond samples representing various genotypes and interspecies hybrids of almond, including almond-peach, were analyzed for protein and peptide content using electrophoresis, Western immunoblotting, and enzyme-linked immunosorbent assay (ELISA). Nondenaturing nondissociating polyacrylamide gel electrophoresis (NDND-PAGE) of the aqueous extracts indicated that a single major storage protein (almond major protein -- AMP or amandin) dominated the total soluble protein composition. Denaturing SDS--PAGE analyses of the aqueous extracts revealed that the AMP was mainly composed of two sets of polypeptides with estimated molecular masses in the ranges of 38--41 kDa and 20--22 kDa, regardless of the source; however, distinct variations in the intensity and electrophoretic mobility of some bands were noted between samples. In addition to AMP, several minor polypeptides were also present in all the genotypes, and variations were seen in these as well. Regardless of the genotype, AMP was recognized in Western blots by rabbit polyclonal anti-AMP antibodies, mouse monoclonal anti-AMP antibodies (mAbs), and serum IgE from patients displaying strong serum anti-almond IgE reactivity. As with protein staining results, antibody reactivity also revealed common patterns but displayed some variation between samples. An anti-AMP inhibition ELISA was used to quantify and compare aqueous extracts for various samples. All samples (n = 60) reacted in this assay with a mean +/- standard deviation (sigma n) = 0.82 +/- 0.18 when compared to reference aqueous extract from Nonpareil designated as 1.0.

Production and characterization of rabbit polyclonal antibodies to almond (Prunus dulcis L.) major storage protein.

Rabbits were immunized with purified almond major protein (AMP), the primary storage protein in almonds. Rabbit anti-AMP polyclonal antibodies (PA) could detect AMP when as little as 1-10 ng/mL were used to coat microtiter plates in a noncompetitive enzyme linked-immunosorbent assay (ELISA). Competitive inhibition ELISA assays detected the AMP down to 300 ng/mL. PA recognized the AMP in protein extracts from all U.S. major marketing cultivars of almonds (Mission, Neplus, Peerless, Carmel, and Nonpareil) with specific reactivity of 52.6-75% as compared to that of the AMP alone. Immunoreactivity of protein extracts prepared from commercial samples of blanched almonds, roasted almonds, and almond paste was respectively reduced by 50.0%, 56.6%, and 68.4% (noncompetitive ELISA) when compared to the immunoreactivity of the AMP. Moist heat (121 degrees C, 15 min) pretreatment of the AMP reduced the PA reactivity by 87% (noncompetitive ELISA). Exposing AMP to pH extremes (12.5 and 1.5-2.5) caused a 53% and 57% reduction in PA reactivity, respectively (noncompetitive ELISA). PA showed some cross-reactivity with the cashew major globulin, and to a lesser extent, the Tepary and Great Northern bean major storage protein (7S or phaseolin). The presence of almonds in a commercial food was detected using PA in a competitive ELISA.

Identification and cloning of a complementary DNA encoding a vicilin-like proprotein, jug r 2, from english walnut kernel (Juglans regia), a major food allergen.

BACKGROUND: Walnuts and other tree nuts are important food-allergen sources that have the potential to be associated with life-threatening, IgE-mediated systemic reactions in some individuals. OBJECTIVE: The purpose of this study was to characterize a complementary (c)DNA clone encoding one of the walnut food allergens. METHODS: A cDNA expression library prepared from walnut somatic embryo was screened for IgE reactivity with patient serum. A reactive clone of 2060 bp, which encoded a protein of 593 amino acids in length, was subcloned by excision into the pGEX expression vector. IgE-binding inhibition experiments were performed. RESULTS: A recombinant fusion protein was induced and shown to bind serum IgE from 9 of 15 patients tested, thus identifying a major allergen. This clone, named Jug r 2, exhibited significant homology with genes encoding the vicilin group of seed proteins. An IgE-binding inhibition experiment suggested that the encoded protein undergoes posttranslational modification into at least one major polypeptide (47 kd) and possibly several others, which is similar to the vicilin-like proteins characterized in cocoa bean (Theobroma cacao) and cottonseed (Gossypium hirsutum). N-terminal sequencing of the 47-kd band, Jug r 2, identified it as a mature protein obtained from the precursor. A second IgE-binding inhibition experiment showed that there is minimal or no cross-reactivity between Jug r 2 and pea vicilin, peanut proteins, or cacao proteins. CONCLUSION: Jug r 2 is the third vicilin food allergen identified in addition to vicilins from soy and peanut. The availability of recombinant food allergens should help advance studies on the immunopathogenesis and possible treatment of IgE-mediated food hypersensitivity.

Systemic allergic reaction to coconut (Cocos nucifera) in 2 subjects with hypersensitivity to tree nut and demonstration of cross-reactivity to legumin-like seed storage proteins: new coconut and walnut food allergens.

BACKGROUND: Two patients with tree nut allergy manifested by life-threatening systemic reactions reported the subsequent onset of systemic reactions after the consumption of coconut. OBJECTIVE: Herein, the IgE-binding proteins from coconut are described, and in vitro cross-reactivity with other nuts is investigated. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Severe migratory granulomatous reactions to silicone gel in 3 patients.

In humans implanted with silicone gel breast prostheses, a mild foreign body response results in the formation of a collagenous capsule around the prosthesis. Although many such patients may show evidence of a microscopic granulomatous foreign body reaction upon examination of capsular material at explantation of a prosthesis, it is unusual to have large, palpable granulomas, even in the presence of rupture or leakage. Rare patients have had severe local inflammation and complications resulting from silicone migration to the axilla, arm, or abdominal wall. We describe 3 patients who had deforming granulomas after implant rupture, along with other consequences of silicone gel migrating down the upper extremity. Silicone gel, once it leaves the implant, is not biologically inert and in some persons can elicit profound pathologic responses.

An unproven technique with potentially fatal outcome: provocation/neutralization in a patient with systemic mastocytosis.

OBJECTIVE: To describe the risks associated with use of an unproven technique, provocation/neutralization, in diagnosis and treatment of a putative "food allergy" in a patient with systemic mastocytosis. METHODS: A case report of a 68-year-old woman with mastocytosis is reported. The patient was interviewed, examined, and all medical records were reviewed. Photos were taken, and skin and colonic biopsies were performed. RESULTS: The patient was previously diagnosed with urticaria pigmentosa but also had significant diarrhea that was well-controlled by oral cromolyn sodium. She saw a physician who practiced provocation/neutralization and was told that food allergies were the cause of her gastrointestinal symptoms. She was placed on "neutralizing" injections of milk and wheat, but experienced flushing, palpitations, and lightheadedness with syncope upon injections into her thigh, which is a skin area highly involved by visible lesions of cutaneous mastocytosis. Later evaluation revealed increased numbers of mast cells in her colonic mucosa as well as confirmation of cutaneous mastocytosis. CONCLUSIONS: The patient's previous history of urticaria pigmentosa, orally communicated by the patient, documented in medical records, and easily visible on physical examination, was discounted by a practitioner of an alternative and unproven medical treatment, provocation/neutralization. She subsequently had potentially life-threatening reactions to "provocative" skin testing and "neutralizing" injections. Patients with systemic mastocytosis are at risk for significant mast cell mediator release during immunotherapy, conventional or alternative.

Cloning and sequencing of a gene encoding a 2S albumin seed storage protein precursor from English walnut (Juglans regia), a major food allergen.

BACKGROUND: Walnuts rank third in per capita consumption of tree nuts in the United States and can be associated with systemic IgE-mediated reactions in some individuals. OBJECTIVE: The objectives of the study were to clone a gene encoding one of the major food allergens in the walnut kernel and to characterize the recombinant allergen. METHODS: A cDNA expression library in the lambda vector Uni-ZAP, which was prepared from walnut somatic embryos, was screened by using a patient's sera that reacted with multiple protein bands on immunoblotting. RESULTS: A cDNA clone containing an insert of 663 bp was identified and named Jug r 1. DNA sequence analysis of this clone revealed that it encoded a protein 142 amino acids in length. Comparison of the encoded protein sequences with protein databases revealed that this clone exhibits a 46.1% identity with the Brazil nut (Bertholletia excelsa) methionine-rich 2S albumin seed storage protein precursor, Ber e 1. Jug r 1 appears to be an important walnut food allergen; 12 of 16 sera from patients allergic to walnuts demonstrated IgE binding to the 2S albumin seed storage protein precursor fusion protein. An IgE-binding inhibition study suggests that the walnut 2S protein precursor undergoes posttranslational modification into a large and small subunit that is similar to castor seed, cottonseed, mustard seed, and Brazil nut 2S seed storage protein allergens. Interestingly, the gene encoding this allergenic protein in Brazil nuts has recently gained notoriety because of its experimental use as a transgene to enhance the nutritional quality of legumes. CONCLUSION: This is now the sixth definitive 2S albumin seed storage protein demonstrated to bind IgE, suggesting that this class of proteins is inherently allergenic.

Allergenicity of gourmet nut oils processed by different methods.

BACKGROUND: No information is available on allergenicity of tree nut oils, and information on peanut oils has been conflicting. Many of the nut oils now on the market undergo minimal processing and may contain residual antigen. OBJECTIVE: This study was carried out to determine whether several of the new "gourmet" tree nut oils, as well as peanut oils, contain residual proteins that could bind IgE from sera of patients with allergy. METHODS: Several brands of walnut, almond, hazelnut, pistachio, and macadamia nut oils were examined. Peanut oils, both unrefined oils (which have been shown to contain allergenic proteins) and refined oils (without previously demonstrable allergens), were also examined to confirm reproducibility of immunoreactivity as reported by other investigators. Oils were extracted with 0.2 mol/L ammonium bicarbonate, and protein concentrations in the aqueous extracts were measured. IgE binding was assayed by slot-blot and Western immunoblotting. Pooled sera from patients with a history of systemic reactions to various tree nuts or peanuts were used as appropriate. RESULTS: The oil extracts known to be from oils that had undergone less processing at lower temperatures tended to demonstrate qualitatively greater IgE binding and higher protein concentrations. CONCLUSIONS: Tree nut and peanut oils may pose a threat to patients with allergy, depending on the method of manufacture and processing.

Lack of autoantibody expression in children born to mothers with silicone breast implants.

OBJECTIVE: We determined systematically the prevalence of autoantibodies in children born to mothers with silicone breast implants and the relationships with clinical symptoms and methods of exposure. METHODS: Autoantibody expression was determined in 80 children born to mothers with silicone implants and in 42 controls. A clinical assessment score was assigned to each patient. Antinuclear antibodies as well as antibodies to mitochondrial, smooth muscle, striational, myocardial, parietal cell, reticulin tissues, or subcellular compartments were measured by indirect fluorescent assay. Antibodies to nRNP (U1-RNP/snRNP); Sm; SS-A; SS-B; Scl-70; thyroid microsome; immunoglobulin (Ig)G, IgM, and IgA antibodies to cardiolipin; and antibodies to native and denatured human types I and II collagen were measured by enzyme-linked immunosorbent assay. Serum complement components C3 and C4 and IgM rheumatoid factor were measured by nephelometry. RESULTS: Autoantibody prevalence was not significantly different between children born to mothers with silicone implants and controls. The presence of autoantibodies was not related to the children's clinical symptoms or to the method of exposure. CONCLUSIONS: Determination of autoantibody production is of limited clinical utility in the evaluation of children born to mothers with silicone breast implants.