389 resultados para peanut
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In-shell, peeled and blanched peanut samples were characterized in relation to proximate composition and fatty acid profile. No difference was found in relation to its proximate composition. The three major fatty acids were palmitic acid, oleic acid, and linoleic acid. In order to investigate irradiation and storage effects, peanut samples were submitted to doses of 0.0, 5.0, 7.5 or 10.0 kGy, stored for six months at room temperature and monitored every three months. Peanuts responded differently to irradiation, particularly with regards to tocopherol contents, primary and secondary oxidation products and oil stability index. Induction periods and tocopherol contents were negatively correlated with irradiation doses and decreased moderately during storage. alpha-Tocopherol was the most gamma radiation sensitive and peeled samples were the most affected. A positive correlation was found among tocopherol contents and the induction period of the oils extracted from irradiated samples. Gamma radiation and storage time increased oxidation compounds production. If gamma radiation is considered an alternative for industrial scale peanut conservation, in-shell samples are the best feedstock. For the best of our knowledge this is the first article with such results; this way it may be helpful as basis for future studies on gamma radiation of in-shell crops.
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Aspergillus flavus, a haploid organism found worldwide in a variety of crops, including maize, cottonseed, almond, pistachio, and peanut, causes substantial and recurrent worldwide economic liabilities. This filamentous fungus produces aflatoxins (AFLs) B1 and B2, which are among the most carcinogenic compounds from nature, acutely hepatotoxic and immunosuppressive. Recent efforts to reduce AFL contamination in crops have focused on the use of nonaflatoxigenic A. flavus strains as biological control agents. Such agents are applied to soil to competitively exclude native AFL strains from crops and thereby reduce AFL contamination. Because the possibility of genetic recombination in A. flavus could influence the stability of biocontrol strains with the production of novel AFL phenotypes, this article assesses the diversity of vegetative compatibility reactions in isolates of A. flavus to identify heterokaryon self-incompatible (HSI) strains among nonaflatoxigenic isolates, which would be used as biological controls of AFL contamination in crops. Nitrate nonutilizing (nit) mutants were recovered from 25 A. flavus isolates, and based on vegetative complementation between nit mutants and on the microscopic examination of the number of hyphal fusions, five nonaflatoxigenic (6, 7, 9 to 11) and two nontoxigenic (8 and 12) isolates of A. flavus were phenotypically characterized as HSI. Because the number of hyphal fusions is reduced in HSI strains, impairing both heterokaryon formation and the genetic exchanges with aflatoxigenic strains, the HSI isolates characterized here, especially isolates 8 and 12, are potential agents for reducing AFL contamination in crops
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Introduction 1.1 Occurrence of polycyclic aromatic hydrocarbons (PAH) in the environment Worldwide industrial and agricultural developments have released a large number of natural and synthetic hazardous compounds into the environment due to careless waste disposal, illegal waste dumping and accidental spills. As a result, there are numerous sites in the world that require cleanup of soils and groundwater. Polycyclic aromatic hydrocarbons (PAHs) are one of the major groups of these contaminants (Da Silva et al., 2003). PAHs constitute a diverse class of organic compounds consisting of two or more aromatic rings with various structural configurations (Prabhu and Phale, 2003). Being a derivative of benzene, PAHs are thermodynamically stable. In addition, these chemicals tend to adhere to particle surfaces, such as soils, because of their low water solubility and strong hydrophobicity, and this results in greater persistence under natural conditions. This persistence coupled with their potential carcinogenicity makes PAHs problematic environmental contaminants (Cerniglia, 1992; Sutherland, 1992). PAHs are widely found in high concentrations at many industrial sites, particularly those associated with petroleum, gas production and wood preserving industries (Wilson and Jones, 1993). 1.2 Remediation technologies Conventional techniques used for the remediation of soil polluted with organic contaminants include excavation of the contaminated soil and disposal to a landfill or capping - containment - of the contaminated areas of a site. These methods have some drawbacks. The first method simply moves the contamination elsewhere and may create significant risks in the excavation, handling and transport of hazardous material. Additionally, it is very difficult and increasingly expensive to find new landfill sites for the final disposal of the material. The cap and containment method is only an interim solution since the contamination remains on site, requiring monitoring and maintenance of the isolation barriers long into the future, with all the associated costs and potential liability. A better approach than these traditional methods is to completely destroy the pollutants, if possible, or transform them into harmless substances. Some technologies that have been used are high-temperature incineration and various types of chemical decomposition (for example, base-catalyzed dechlorination, UV oxidation). However, these methods have significant disadvantages, principally their technological complexity, high cost , and the lack of public acceptance. Bioremediation, on the contrast, is a promising option for the complete removal and destruction of contaminants. 1.3 Bioremediation of PAH contaminated soil & groundwater Bioremediation is the use of living organisms, primarily microorganisms, to degrade or detoxify hazardous wastes into harmless substances such as carbon dioxide, water and cell biomass Most PAHs are biodegradable unter natural conditions (Da Silva et al., 2003; Meysami and Baheri, 2003) and bioremediation for cleanup of PAH wastes has been extensively studied at both laboratory and commercial levels- It has been implemented at a number of contaminated sites, including the cleanup of the Exxon Valdez oil spill in Prince William Sound, Alaska in 1989, the Mega Borg spill off the Texas coast in 1990 and the Burgan Oil Field, Kuwait in 1994 (Purwaningsih, 2002). Different strategies for PAH bioremediation, such as in situ , ex situ or on site bioremediation were developed in recent years. In situ bioremediation is a technique that is applied to soil and groundwater at the site without removing the contaminated soil or groundwater, based on the provision of optimum conditions for microbiological contaminant breakdown.. Ex situ bioremediation of PAHs, on the other hand, is a technique applied to soil and groundwater which has been removed from the site via excavation (soil) or pumping (water). Hazardous contaminants are converted in controlled bioreactors into harmless compounds in an efficient manner. 1.4 Bioavailability of PAH in the subsurface Frequently, PAH contamination in the environment is occurs as contaminants that are sorbed onto soilparticles rather than in phase (NAPL, non aqueous phase liquids). It is known that the biodegradation rate of most PAHs sorbed onto soil is far lower than rates measured in solution cultures of microorganisms with pure solid pollutants (Alexander and Scow, 1989; Hamaker, 1972). It is generally believed that only that fraction of PAHs dissolved in the solution can be metabolized by microorganisms in soil. The amount of contaminant that can be readily taken up and degraded by microorganisms is defined as bioavailability (Bosma et al., 1997; Maier, 2000). Two phenomena have been suggested to cause the low bioavailability of PAHs in soil (Danielsson, 2000). The first one is strong adsorption of the contaminants to the soil constituents which then leads to very slow release rates of contaminants to the aqueous phase. Sorption is often well correlated with soil organic matter content (Means, 1980) and significantly reduces biodegradation (Manilal and Alexander, 1991). The second phenomenon is slow mass transfer of pollutants, such as pore diffusion in the soil aggregates or diffusion in the organic matter in the soil. The complex set of these physical, chemical and biological processes is schematically illustrated in Figure 1. As shown in Figure 1, biodegradation processes are taking place in the soil solution while diffusion processes occur in the narrow pores in and between soil aggregates (Danielsson, 2000). Seemingly contradictory studies can be found in the literature that indicate the rate and final extent of metabolism may be either lower or higher for sorbed PAHs by soil than those for pure PAHs (Van Loosdrecht et al., 1990). These contrasting results demonstrate that the bioavailability of organic contaminants sorbed onto soil is far from being well understood. Besides bioavailability, there are several other factors influencing the rate and extent of biodegradation of PAHs in soil including microbial population characteristics, physical and chemical properties of PAHs and environmental factors (temperature, moisture, pH, degree of contamination). Figure 1: Schematic diagram showing possible rate-limiting processes during bioremediation of hydrophobic organic contaminants in a contaminated soil-water system (not to scale) (Danielsson, 2000). 1.5 Increasing the bioavailability of PAH in soil Attempts to improve the biodegradation of PAHs in soil by increasing their bioavailability include the use of surfactants , solvents or solubility enhancers.. However, introduction of synthetic surfactant may result in the addition of one more pollutant. (Wang and Brusseau, 1993).A study conducted by Mulder et al. showed that the introduction of hydropropyl-ß-cyclodextrin (HPCD), a well-known PAH solubility enhancer, significantly increased the solubilization of PAHs although it did not improve the biodegradation rate of PAHs (Mulder et al., 1998), indicating that further research is required in order to develop a feasible and efficient remediation method. Enhancing the extent of PAHs mass transfer from the soil phase to the liquid might prove an efficient and environmentally low-risk alternative way of addressing the problem of slow PAH biodegradation in soil.
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Die phylogenetische Position der Mollusken innerhalb der Trochozoa sowie die interne Evolution der Klassen der Mollusca sind weitgehend unbekannt und wurden in meiner Arbeit anhand molekularer Merkmale untersucht. Phylogenomische Analysen zeigten in der Vergangenheit eine gute Auflösung für ursprüngliche Speziationsereignisse. Daher wurden hier drei neue EST Datensätze generiert: für Sipunculus nudus (Sipuncula), Barentsia elongata (Kamptozoa) und Lepidochitona cinerea, (Polyplacophora, Mollusca). Zusätzlich wurden gezielt Gene verschiedener Mollusken mittels RT-PCR amplifiziert. rnSowohl Kamptozoen als auch Sipunculiden wurden aufgrund morphologischer Kriterien bisher als mögliche Schwestergruppe der Mollusken gehandelt, aber die hier erzielten Ergebnisse zur Evolution der Hämerythrine, Gen-Anordnungen der mitochondrialen Genome und phylogenetische Analysen der ribosomalen und der mitochondriellen Proteine stützen diese Hypothese nicht. Die Position der Kamptozoa erwies sich hier generell als unbeständig; phylogenomische Analysen deuten eine Nähe zu den Bryozoen an, aber diese Position wird stark durch die Auswahl der Taxa beeinflusst. Dagegen weisen meine Analysen klar auf eine nähere Beziehung zwischen Annelida und Sipuncula hin. Die ribosomalen Proteine zeigen Sipuncula (und Echiura) sogar als Subtaxa der Anneliden. Wie den Mollusken fehlt den Sipunculiden jegliche Segmentierung und meine Ergebnisse legen hier die Möglichkeit des Verlusts dieses Merkmals innerhalb der Anneliden bei den Sipunculiden nahe. Innerhalb der Mollusken wurden die Solenogastren bereits als Schwestergruppe aller rezenten Mollusken vorgeschlagen. Im Rahmen meiner Arbeit wurden von drei verschiedenen Solenogastren-Arten die ersten zuverlässigen 18S rRNA-Sequenzen ermittelt, und es zeigte sich, dass alle bisher veröffentlichten 18S-Sequenzen dieser Molluskenklasse höchst unvollständig oder fehlerhaft sind. rnRibosomale Proteine sind gute phylogenetische Marker und hier wurden die Auswahl und Anzahl dieser Gene für phylogenetische Analysen optimiert. Über Sonden-basierte Detektion wurde eine sampling-Strategie getestet, die im Vergleich mit standard-phylogenomischen Ansätzen zukünftige molekulare Stammbaumrekonstruktionen mit größerem Taxonsampling ermöglicht.rn
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Over the last decades the prevalence of food allergies has continually increased on a world wide scale. While there are effective treatments available for bee and wasp venom allergic patients, there is currently no established therapy for the treatment of severe food allergies. Aim of the project was to genetically fuse different food allergens with the immune modulating Toll-like receptor 5 (TLR5)-ligand flagellin and to test these constructs for their immune modulatory capacities both in vitro and in vivo. Chicken ovalbumin (Ova) as model antigen, Pru p 3, and Ara h 2 the respective major allergens from peach and peanut were used as allergens. The potential vaccine candidates were characterized by protein biochemical methods (purity, folding, endotoxin contaminations). Moreover, their immune modulating effects on cell culture lines (TLR5-receptor activation) and primary mouse immune cells (myeloid and plasmacytoid dendritic cells) were investigated. Additionally, the prophylactic and therapeutic use of the flagellin Ova fusion protein (rflaA:Ova) were investigated in a mouse model of intestinal allergy. In myeloid dendritic cells (mDC) stimulation with the fusion proteins led to a strong cell activation and cytokine secretion. Here, the fusion proteins proved to be a much stronger stimulus than the equimolar amount of both proteins provided alone or as a mixture. Noteworthy, stimulation with rflaA:Ova induced the secretion of the anti-inflammatory cytokine IL-10 from mDC. In co-culture experiments this IL-10 secretion suppressed the Ova-induced secretion of Th1 and Th2 cytokines from Ova-specific CD4 T cells. Using MyD88-deficient mDC this repression of cytokine secretion was shown to be TLR-dependent. Finally, the potency of the rflaA:Ova construct was investigated in a mouse model of Ova-induced intestinal allergy. In a prophylactic vaccination approach rflaA:Ova was shown to prevent the establishment of the intestinal allergy and all associated symptoms (weight loss, temperature drop, soft faeces). This fusion protein-mediated protection was accompanied by a reduced T cell activation, and reduced Th2 cytokines in intestinal homogenates. These effects were paralleled by a strong induction of Ova-specific IgG2a antibodies in rflaA:Ova-vaccinated sera, while Ova-specific IgE antibody production was significantly reduced. Therapeutic vaccination with rflaA:Ova reduced allergic symptoms and T cell activation but did not influence weight loss and antibody production. In all in vivo experiments vaccination with both proteins either provided alone or as a mixture did not have comparable effects. Future experiments aim at elucidating the mechanism and further optimization of the therapeutic vaccination approach. The results presented in this thesis demonstrate, that fusion proteins containing flagellin have strong immune modulatory capacities both in vitro and in vivo. Therefore, such constructs are promising vaccine candidates for the therapy of type I allergies.
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The purpose of our study is to investigate the effects of chronic estrogen administration on same-sex interactions during exposure to a social stressor and on oxytocin (OT) levels in prairie voles (Microtus orchrogaster). Estrogen and OT are two hormones known to be involved with social behavior and stress. Estogen is involved in the transcription of OT and its receptor. Because of this, it is generally thought that estrogen upregulates OT, but evidence to support this assumption is weak. While estrogen has been shown to either increase or decrease stress, OT has been shown to have stress-dampening properties. The goal of our experiment is to determine how estrogen affects OT levels as well as behavior in a social stressor in the voles. In addition, estrogen is required for many opposite-sex interactions, but little is known about its influence on same-sex interactions. We hypothesized that prairie voles receiving chronic estrogen injections would show an increase in OT levels in the brain and alter behavior in response to a social stressor called the resident-intruder test. To test this hypothesis, 73 female prairie voles were ovariectomized and then administered daily injections of estrogen (0.05 ¿g in peanut oil, s.c.) or vehicle for 8 days. On the final day of injections, half of the voles were given the resident-intruder test, a stressful 5 min interaction with a same-sex stranger. Their behavior was video-recorded. These animals were then sacrificed either 10 minutes or 60 minutes after the conclusion of the test. Half of the animals (no stress group) were not given the resident-intruder test. After sacrifice, trunk blood and brains were collected from the animals. Videos of the resident-intruder tests were analyzed for pro-social and aggressive behavior. Density of OT-activated neurons in the brain was measured via pixel count using immunohistochemistry. No differences were found in pro-social behavior (focal sniffing, p = 0.242; focal initiated sniffing p = 0.142; focal initiated sniffing/focal sniffing, p = 0.884) or aggressive behavior (total time fighting, p= 0.763; number of fights, p= 0.148; number of strikes, p = 0.714). No differences were found in activation of OT neurons in the brain, neither in the anterior paraventricular nucleus (PVN) (pixel count p= 0.358; % area that contains pixelated neurons p = 0.443) nor in the medial PVN (pixel count p= 0.999; % area that contains pixelated neurons p = 0.916). These results suggest that estrogen most likely does not directly upregulate OT and that estrogen does not alter behavior in stressful social interactions with a same-sex stranger. Estrogen may prepare the animal to respond to OT, instead of increasing the production of the peptide itself, suggesting that we need to shift the framework in which we consider estrogen and OT interactions.
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BACKGROUND Exposure to food allergens through a disrupted skin barrier has been recognized as a potential factor in the increasing prevalence of food allergy. OBJECTIVE We sought to test the immunologic mechanisms by which epicutaneous sensitization to food allergens predisposes to intestinal food allergy. METHODS Mice were epicutaneously sensitized with ovalbumin or peanut on an atopic dermatitis-like skin lesion, followed by intragastric antigen challenge. Antigen-specific serum IgE levels and T(H)2 cytokine responses were measured by ELISA. Expression of type 2 cytokines and mast cell proteases in the intestine were measured by using real-time PCR. Accumulation of basophils in the skin and mast cells in the intestine was examined by using flow cytometry. In vivo basophil depletion was achieved by using diphtheria toxin treatment of Baso-DTR mice. For cell-transfer studies, the basophil population was expanded in vivo by means of hydrodynamic tail vein injection of thymic stromal lymphopoietin (TSLP) cDNA plasmid. RESULTS Sensitization to food allergens through an atopic dermatitis-like skin lesion is associated with an expansion of TSLP-elicited basophils in the skin that promote antigen-specific T(H)2 cytokine responses, increased antigen-specific serum IgE levels, and accumulation of mast cells in the intestine, promoting the development of intestinal food allergy. Critically, disruption of TSLP responses or depletion of basophils reduced the susceptibility to intestinal food allergy, whereas transfer of TSLP-elicited basophils into intact skin promoted disease. CONCLUSION Epicutaneous sensitization on a disrupted skin barrier is associated with accumulation of TSLP-elicited basophils, which are necessary and sufficient to promote antigen-induced intestinal food allergy.
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Eosinophils natively inhabit the small intestine, but a functional role for them there has remained elusive. Here, we show that eosinophil-deficient mice were protected from induction of Th2-mediated peanut food allergy and anaphylaxis, and Th2 priming was restored by reconstitution with il4(+/+) or il4(-/-) eosinophils. Eosinophils controlled CD103(+) dendritic cell (DC) activation and migration from the intestine to draining lymph nodes, events necessary for Th2 priming. Eosinophil activation in vitro and in vivo led to degranulation of eosinophil peroxidase, a granule protein whose enzymatic activity promoted DC activation in mice and humans in vitro, and intestinal and extraintestinal mouse DC activation and mobilization to lymph nodes in vivo. Further, eosinophil peroxidase enhanced responses to ovalbumin seen after immunization. Thus, eosinophils can be critical contributors to the intestinal immune system, and granule-mediated shaping of DC responses can promote both intestinal and extraintestinal adaptive immunity.
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El objetivo fue estudiar la diversidad de coleópteros epígeos en el cultivo de maní, su composición taxonómica y su hábito alimenticio, a fin de aportar conocimientos acerca de especies potencialmente dañinas o benéficas al cultivo. Durante las campañas agrícolas 2004/05, 2005/06 y 2006/07 se colocaron 10 trampas Barber en un lote de maní ubicado en la localidad de Olaeta (Córdoba, Argentina). Se instalaron siguiendo un diseño en "X" dentro del lote en el momento de la siembra del cultivo y se dejaron hasta la cosecha. La colecta se realizó con una frecuencia semanal y el material fue identificado y cuantificado. Se determinó la frecuencia y constancia de cada especie colectada y la riqueza de especies fue calculada a través del Índice de diversidad de Simpson. Se registraron 10 familias y dentro de ellas 19 géneros/especies: los individuos fitófagos representaron entre el 66 y el 71%; los predadores entre el 18 y el 27% y los coprófagos entre el 2 y el 16% en los tres ciclos estudiados. La mayor diversidad (0,80-0,82) se obtuvo entre mediados de diciembre y principios de enero. Las especies fitófagas que se encontraron podrían comportarse como plagas para el cultivo.
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El maní cultivado (Arachis hypogaea L.), es una especie de gran importancia económica, nativo de América del Sur. Se divide en dos subespecies y seis variedades botánicas. Genéticamente es alotetraploide, constituido por dos juegos genómicos duplicados. El empleo de marcadores microsatélites resulta más apropiado para realizar la caracterización genética de esta especie, puesto que permiten detectar un elevado nivel de polimorfismo. El objetivo del presente trabajo fue caracterizar la diversidad genética existente en las entradas de germoplasma de maní cultivado pertenecientes al Banco Activo de Germoplasma de Maní del Instituto Nacional de Tecnología Agropecuaria (INTA). Veinticinco entradas fueron genotipificadas con 23 marcadores microsatélites, de los cuales, 17 resultaron polimórficos. Se observaron 75 fragmentos polimórficos amplificados, con un promedio de 4,41 alelos por locus y un rango de 1 a 9 alelos. El contenido de información polimórfica osciló entre 0,15 y 0,58. El valor de la diversidad genética promedio fue de 0,165. Tanto el análisis de conglomerados como el de coordenadas principales evidenciaron dos grupos, uno formado por los materiales representantes de la subespecie fastigiata y otro por los de la subespecie hypogaea. Los resultados del análisis molecular de la varianza mostraron varianza tanto dentro como entre, las subespecies analizadas.
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The purpose of this research is to explore the extent and significance of possible interacting factors on the viability of stored germplasm. Our work begins with characterizing the kinetics of TAG and water phase changes in peanut (Arachis hypogaea) and Papaya (Carica papaya) seeds equilibrated to different water contents and stored at temperatures between -5 and -80°C. Water and TAG phase was measured using a Perkin Elmer Differential Scanning Calorimeter. Cytoplasm ultra-structure was visualized without chemical fixatives using low temperature scanning electron microscopy (cryo-SEM) performed with a Zeiss DSN 960 scanning microscope equipped with a Cryotrans CT-1500 cold plate (Oxford, UK).
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PAHs are pollutants of concern since they are known carcinogenic compounds. Their occurrence is mainly related to combustion or pyrolysis of organic matter such as fossil fuels. In the current scenario where biofuels are growingly important, it is also necessary to characterize PAH emissions due to their combustion. There are a number of works concerning PAH emissions from biodiesel combustion in Diesel engines, however, there are few regarding the difference between them depending on the feedstock and type of alcohol used in the transesterification. The authors have processed and characterized biodiesel from several feedstocks (Le. tallow, palm, rapeseed, soy-bean, coconut, peanut and linseed oils) to obtain FAME and FAEE and they have developed a method to measure the PAHs originated during their combustion in a bomb calorimeter. The tests have been carried out under different oxygen pressure conditions, and samples have been c1eaned from the bomb after each one of these tests. The samples have been prepared for GC-MS analysis, where PAH quantities among some other combustion products have been assessed. This work shows statistical relations obtained between the measured amounts of 18 PAHs of concern and the composition (oil and type of alcohol) used to obtain the biodiesel, and also the oxygen pressure during combustion.
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In recent years, Independent Components Analysis (ICA) has proven itself to be a powerful signal-processing technique for solving the Blind-Source Separation (BSS) problems in different scientific domains. In the present work, an application of ICA for processing NIR hyperspectral images to detect traces of peanut in wheat flour is presented. Processing was performed without a priori knowledge of the chemical composition of the two food materials. The aim was to extract the source signals of the different chemical components from the initial data set and to use them in order to determine the distribution of peanut traces in the hyperspectral images. To determine the optimal number of independent component to be extracted, the Random ICA by blocks method was used. This method is based on the repeated calculation of several models using an increasing number of independent components after randomly segmenting the matrix data into two blocks and then calculating the correlations between the signals extracted from the two blocks. The extracted ICA signals were interpreted and their ability to classify peanut and wheat flour was studied. Finally, all the extracted ICs were used to construct a single synthetic signal that could be used directly with the hyperspectral images to enhance the contrast between the peanut and the wheat flours in a real multi-use industrial environment. Furthermore, feature extraction methods (connected components labelling algorithm followed by flood fill method to extract object contours) were applied in order to target the spatial location of the presence of peanut traces. A good visualization of the distributions of peanut traces was thus obtained
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Background: Component-based diagnosis on multiplex platforms is widely used in food allergy but its clinical performance has not been evaluated in nut allergy. Objective: To assess the diagnostic performance of a commercial protein microarray in the determination of specific IgE (sIgE) in peanut, hazelnut, and walnut allergy. Methods: sIgE was measured in 36 peanut-allergic, 36 hazelnut-allergic, and 44 walnut-allergic patients by ISAC 112, and subsequently, sIgE against available components was determined by ImmunoCAP in patients with negative ISAC results. ImmunoCAP was also used to measure sIgE to Ara h 9, Cor a 8, and Jug r 3 in a subgroup of lipid transfer protein (LTP)-sensitized nut-allergic patients (positive skin prick test to LTP-enriched extract). sIgE levels by ImmunoCAP were compared with ISAC ranges. Results: Most peanut-, hazelnut-, and walnut-allergic patients were sensitized to the corresponding nut LTP (Ara h 9, 66.7%; Cor a 8, 80.5%; Jug r 3, 84% respectively). However, ISAC did not detect sIgE in 33.3% of peanut-allergic patients, 13.9% of hazelnut-allergic patients, or 13.6% of walnut-allergic patients. sIgE determination by ImmunoCAP detected sensitization to Ara h 9, Cor a 8, and Jug r 3 in, respectively, 61.5% of peanut-allergic patients, 60% of hazelnut-allergic patients, and 88.3% of walnut-allergic patients with negative ISAC results. In the subgroup of peach LTP?sensitized patients, Ara h 9 sIgE was detected in more cases by ImmunoCAP than by ISAC (94.4% vs 72.2%, P<.05). Similar rates of Cor a 8 and Jug r 3 sensitization were detected by both techniques. Conclusions: The diagnostic performance of ISAC was adequate for hazelnut and walnut allergy but not for peanut allergy. sIgE sensitivity against Ara h 9 in ISAC needs to be improved.
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The incidence of Amaranthaceae pollen allergy has increased due to the desertification occurring in many countries. In some regions of Spain, Salsola kali is the main cause of pollinosis, at almost the same level as olive and grass pollen. Sal k 1 - the sensitization marker of S. kali pollinosis - is used in clinical diagnosis, but is purified at a low yield from pollen. We aimed to produce a recombinant (r)Sal k 1 able to span the structural and immunological properties of the natural isoforms from pollen, and validate its potential use for diagnosis. METHODS: Specific cDNA was amplified by PCR, cloned into the pET41b vector and used to transform BL21 (DE3) Escherichia coli cells. Immunoblotting, ELISA, basophil activation and skin-prick tests were used to validate the recombinant protein against Sal k 1 isolated from pollen. Sera and blood cells from S. kali pollen-sensitized patients and specific monoclonal and polyclonal antisera were used. RESULTS: rSal k 1 was produced in bacteria with a yield of 7.5 mg/l of cell culture. The protein was purified to homogeneity and structural and immunologically validated against the natural form. rSal k 1 exhibited a higher IgE cross-reactivity with plant-derived food extracts such as peanut, almond or tomato than with pollen sources such as Platanus acerifolia and Oleaceae members. CONCLUSIONS: rSal k 1 expressed in bacteria retains intact structural and immunological properties in comparison to the pollen-derived allergen. It spans the immunological properties of most of the isoforms found in pollen, and it might substitute natural Sal k 1 in clinical diagnosis.