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Cross-reactions between Polistes dominula and Vespula species are common in southern Europe. Currently, only CAP-inhibition demonstrates high accuracy in identifying genuine sensitizations, but this method is time-consuming and expensive, so a new approach is required. This study investigates skin tests, molecular diagnostics, total IgE (tIgE), and the Ves v 5/Pol d 5 (or vice versa) ratio. The ratio generated low-accuracy results and poor agreement with CAP-inhibition, and we did not find any agreement between CAP-inhibition test and double values of Ves v 5/Pol d 5. Nevertheless, a slight diagnostic improvement was obtained when Ves v 5/tIgE and Pol d 5/tIgE were measured. [ABSTRACT FROM AUTHOR]

Background: Cross-reactivity reactions between allergenic polygalacturonases (PGs) from different biological sources, especially foods and pollens from the Oleaceae family, have been described using Salsola kali PG (Sal k 6). No PG from olive pollen has been characterized to date, hampering further knowledge about cross-reactions through PGs. Objectives: The aim of this work was to determine the potential allergenicity of the PG from olive pollen and clarify its role in cross-reactivity. Methods: A cDNA-encoding olive pollen PG sequence was subcloned into the pET41b vector and used to transform BL21(DE3) Escherichia coli cells to produce a His-tag fusion recombinant protein. The allergenic properties of olive pollen PG were determined by immunoblotting and ELISA in comparison to Sal k 6. The cross-reactivity potential of the protein with other pollen sources was analyzed by inhibition immunoassays. Results: The existence of other isoforms of Ole e 14 with different allergenicity was confirmed by proteomics and a meta-analysis of the recently reported olive genome. Sal k 6 showed a higher IgE recognition than Ole e 14 regardless of patient sensitization, suggesting the existence of more allergenic Ole e 14 isoforms in olive pollen. IgG and IgE inhibition assays supported the existence of cross-reactions between them and with other PGs from Oleaceae and Poaceae plant families. Conclusions: A new allergen from olive pollen, Ole e 14, has been identified, produced as a recombinant isoform, and structurally and immunologically characterized. Its role in cross-reactivity has been confirmed and, due to its smaller IgE binding capacity, it could have an important role for therapeutic purposes. [ABSTRACT FROM AUTHOR]

We present the case of a 77-year-old female patient who suffered from severe anaphylaxis during wound care. Allergologic evaluation yielded specific IgE antibodies to chlorhexidine, but anaphylaxis to chlorhexidine was not congruent with the patient history and dermal provocation tests. However, skin prick tests provided evidence for a sensitization to polyhexanide that was further supported by the detection of specific IgE antibodies to polyhexanide, the results of basophil activation tests and IgE inhibition analysis. We presume cross-reactive IgE antibodies binding to both biguanide antiseptics and identified polyhexanide as the likely cause of the anaphylactic reaction. We recognize polyhexanide as an emerging allergen that has to be considered as a cause of anaphylaxis. [ABSTRACT FROM AUTHOR]

Allergies caused by mosquito bites may produce local or systemic reactions. The inhalation of mosquito allergens may also cause asthma and/or allergic rhinoconjunctivitis in sensitized individuals. The mechanisms implicated in the development of these immune responses involve IgE antibodies, different subtypes of IgG and proinflammatory cytokines as well as basophils, eosinophils and mast cells. Several allergenic components have been identified in the saliva and bodies of mosquitoes and some of these are present in different mosquito species. The most common species implicated in allergic reactions belong to the genera Aedes, Culex and Anopheles. Several Aedes aegypti allergens have been cloned and sequenced. The recombinant molecules show IgE reactivity similar to that of the native allergens, making them good candidates for the diagnosis of mosquito allergies. Allergen-specific immunotherapy with mosquito extracts induces a protective response characterized by a decreased production of IgE antibodies, increased IgG levels, a reduction in the severity of cutaneous and respiratory symptoms and the need for medication. The aims of this review are to summarize the progress made in the characterization of mosquito allergens and discuss the types of immune responses induced by mosquito bites and the inhalation of mosquito allergens in atopic individuals. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Anti-sperm antibodies (ASA) have been de-scribed to be involved in immunological infertility. A possi-ble antigen for ASA is the human cystelne-rlch secretory pro-tein 2 (CRISP-2), a sperm surface protein important in sperm-oocyte interaction. Furthermore, anti-CRISP-2 antibodies were shown to decrease fertility rates in vitro. Recently, we have reported cross-reacting antibodies recognizing CRISP-2 and antigen 5 from yellow jacket venom (Ves v 5) in human serum. Methods: Here, we investigated anti-Ves v 5 and CRISP-2 antibodies in sera from two groups of donors: MAR+ and MAR- patients. Results: A higher incidence of allergy against hymenoptera venom was found in MAR+ patients. Interestingly, affinity-purified ASA from MAR+ patients' sera reacted against both Ves v 5 and CRISP-2, leading to sperm immobilization. Immunofluorescence analysis showed that ASA bound to the sperm surface, including the head part where CRISP-2 is localized. Conclusion: Taken together, these results showed a higher Incidence of antibodies crossreacting with Ves v 5 and CRISP-2 in MAR+ patients. This leads to the hypothesis that MAR+ patients may have a high-er risk to develop wasp allergy. [ABSTRACT FROM AUTHOR]

Background: Anti-sperm antibodies (ASA) have been described to be involved in immunological infertility. A possible antigen for ASA is the human cysteine-rich secretory protein 2 (CRISP-2), a sperm surface protein important in sperm-oocyte interaction. Furthermore, anti-CRISP-2 antibodies were shown to decrease fertility rates in vitro. Recently, we have reported cross-reacting antibodies recognizing CRISP-2 and antigen 5 from yellow jacket venom (Ves v 5) in human serum. Methods: Here, we investigated anti-Ves v 5 and CRISP-2 antibodies in sera from two groups of donors: MAR+ and MAR- patients. Results: A higher incidence of allergy against hymenoptera venom was found in MAR+ patients. Interestingly, affinity-purified ASA from MAR+ patients' sera reacted against both Ves v 5 and CRISP-2, leading to sperm immobilization. Immunofluorescence analysis showed that ASA bound to the sperm surface, including the head part where CRISP-2 is localized. Conclusion: Taken together, these results showed a higher incidence of antibodies cross-reacting with Ves v 5 and CRISP-2 in MAR+ patients. This leads to the hypothesis that MAR+ patients may have a higher risk to develop wasp allergy. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: The existence of IgE binding to dog dander extract without IgE antibodies against the described dog allergens (Can f 1, 2, 3 and 4) implies the presence of other dog allergens yet to be identified. Recently, an IgE-binding protein was isolated from dog urine and identified as prostatic kallikrein; it has been named Can f 5. Cross-reactivity between a dog dander allergen and human prostate-specific antigen (PSA) has been described. The aim of this study was to identify the dog dander allergen that presents cross-reactivity with PSA and demonstrate its clinical relevance in our patient with human seminal plasma allergy. Methods: SDS-PAGE immunoblotting and inhibition tests were performed. Mass spectrometry was carried out to identify the protein involved in the allergy reactions. Results: SDS-PAGE immunoblotting-inhibition with an IgE-binding protein from dog prostatic secretion showed total IgE binding inhibition to a 28-kDa IgE-reactive band identified as PSA. The electroeluted protein from dog prostatic secretion was identified by mass spectrometry as Can f 5. IgE immunoblotting of human seminal plasma incubated with the serum of the patient revealed two IgE-binding bands (28 and 32.7 kDa). Both SDS-PAGE immunoblotting inhibition assays, with human seminal plasma or purified PSA in solid phase, showed complete IgE binding inhibition when the serum of the anaphylactic patient was preincubated with dog dander extract or recombinant Can f 5. Conclusions: The dog dander allergen that shows cross-reactivity with human PSA has been characterized and turns out to be the recently described Can f 5. We demonstrated the clinical relevance of this cross-reactivity in a patient. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Cow's milk allergy (CMA) is an important problem worldwide and the development of an in vivo system to study new immunotherapeutic strategies is of interest. Intolerance to soybean formula has been described in CMA patients, but it is not fully understood. In this work, we used a food allergy model in BALB/c mice to study the cross-reactivity between cow's milk protein (CMP) and soy proteins (SP). Methods: Mice were orally sensitized with cholera toxin and CMP, and then challenged with CMP or SP to induce allergy. Elicited symptoms, plasma histamine, humoral and cellular immune response were analyzed. Th1- and Th2-associated cytokines and transcription factors were assessed at mucosal sites and in splenocytes. Cutaneous tests were also performed. Results: We found that the immediate symptoms elicited in CMP-sensitized mice orally challenged with SP were consistent with a plasma histamine increase. The serum levels of CMP-specific IgE and IgG1 antibodies were increased. These antibodies also recognized soy proteins. Splenocytes and mesenteric lymph node cells incubated with CMP or SP secreted IL-5 and IL-13. mRNA expression of Th2-associated genes (IL-5, IL-13, and GATA-3) was upregulated in mucosal samples. In addition, sensitized animals exhibited positive cutaneous tests after the injection of CMP or SP. Conclusions: We demonstrate that CMP-sensitized mice, without previous exposure to soy proteins, elicited hypersensitivity signs immediately after the oral administration of SP, suggesting that the immunochemical cross-reactivity might be clinically relevant. This model may provide an approach to further characterize cross-allergenicity phenomena and develop new immunotherapeutic treatments for allergic patients. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Booklice (Liposcelis bostrichophila) are a common household insect pest distributed worldwide. Particularly in Japan, they infest 'tatami' mats and are the most frequently detected insect among all detectable insects, present at a frequency of about 90% in dust samples. Although it has been hypothesized that they are an important indoor allergen, studies on their allergenicity have been limited. Methods: To clarify the allergenicity of booklice and the cross-reactivity of this insect allergen with allergens of other insects, patients sensitized to booklice were identified from 185 Japanese adults with allergic asthma using skin tests and IgE-ELISA. IgE-inhibition analysis, immunoblotting and immunoblotting-inhibition analysis were performed using sera from these patients. Allergenic proteins contributing to specific sensitization to booklice were identified by two-dimensional electrophoresis and two-dimensional immunoblotting. Results: The booklouse-specific IgE antibody was detected in sera from 41 patients (22% of studied patients). IgE inhibition analysis revealed that IgE reactivity to the booklouse allergen in the sera from one third of booklouse-sensitized patients was not inhibited by preincubation with extracts from any other environmental insects in this study. Immunoblotting identified a 26-kD protein from booklouse extract as the allergenic protein contributing to specific sensitization to booklice. The amino acid sequence of peptide fragments of this protein showed no homology to those of previously described allergenic proteins, indicating that this protein is a new allergen. Conclusions: Sensitization to booklice was relatively common and specific sensitization to this insect not related to insect panallergy was indicated in this population. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Shrimp is a frequent cause of food allergy worldwide. Besides tropomyosin, several allergens have been described recently. Objective: We investigated which allergens are involved in Italian shrimp-allergic adults. Methods: Sera from 116 shrimp-allergic patients selected in 14 Italian allergy centers were studied. Skin prick tests with house dust mite (HDM) as well as measurements of IgE to Pen a 1 (shrimp tropomyosin) and whole shrimp extract were performed. All sera underwent shrimp immunoblot analysis, and inhibition experiments using HDM extract as inhibitor were carried out on some Pen a 1-negative sera. Results: Immunoblots showed much variability. IgE reactivity at about 30 kDa (tropomyosin) was found in <50% of cases, and reactivity at about 67 kDa and >90 kDa was frequent. Further reactivities at 14-18, 25, 43-50, about 60 and about 80 kDa were detected. Most subjects had a history of shrimp-induced systemic symptoms irrespective of the relevant allergen protein. IgE to Pen a 1 were detected in sera from 46 (41%) patients. Skin reactivity to HDM was found in 43/61 (70%) Pen 1-negative subjects and inhibition studies showed that pre-adsorption of sera with HDM extract induced a marked weakening of the signal at >67 kDa. Conclusions: Several allergens other than tropomyosin are involved in shrimp allergy in adult Italian patients. Some hitherto not described high molecular weight allergens seem particularly relevant in this population and their cross-reactivity with HDM allergens makes them novel potential panallergens of invertebrates. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Peanut and tree nut allergies are life-threatening conditions for many affected individuals worldwide. Currently there is no cure. While co-allergy to peanut and tree nuts is a common clinical observation, and IgE cross-reactivity between peanut and tree nuts is reported, T cell cross-reactivity is poorly defined. Methods: Hazelnut-specific T cell lines were established using peripheral blood mononuclear cells from 5 subjects with co-allergy to hazelnut and peanut. These lines were stimulated with hazelnut and peanut extracts and purified major peanut allergens, Ara h 1 and Ara h 2. Proliferation was determined by 3H-thymidine incorporation and secretion of key Th1 (IFN-γ) and Th2 (IL-5) cytokines analysed by ELISA. Results: Hazelnut-specific T cell lines from all 5 subjects proliferated upon stimulation with both hazelnut and peanut extracts and for 4 subjects, to Ara h 1 and/or Ara h 2. Proliferating cells were mainly CD4+ T cells and produced both IL-5 and IFN-γ in response to hazelnut and peanut stimulation. Mitogenicity of extracts and allergens was excluded by their lack of stimulation of house dust mite-specific T cells. Conclusion: Our finding that hazelnut and peanut co-allergy is associated with cross-reactive T cell responses, driven partly by cross-reactivity to the major peanut allergens Ara h 1 and Ara h 2, points to future development of allergen immunotherapy by targeting cross-reactive T cells. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Profilins are ubiquitous proteins, present in all eukaryotic cells and identified as allergens in pollen, latex and plant foods. The highly conserved structure justifies the cross-reactive nature of IgE antibodies against plant profilins and their designation as pan-allergens. Primary sensitization to profilin seems to arise from pollen sensitization with later development of cross-reactive IgE antibodies against plant food (and possibly latex) profilins. The role of profilin in inducing allergic symptoms needs to be evaluated and raises important issues in allergy diagnosis due to cross-reactivity. IgE cross-reactivity among profilins is associated with multiple pollen sensitization and with various pollen-food syndromes. In respiratory allergy, sensitization to pollen to which the patient has virtually no environmental exposure has been identified as a manifestation of profilin sensitization. As a food allergen, profilin usually elicits mild reactions, such as oral allergy syndrome, is not modified by processing and is especially important in allergy to some fruits, such as melon, watermelon, banana, tomato, citrus fruit and persimmon. Purified natural and recombinant profilins for in vitro and in vivo allergy tests are helpful in the diagnostic work-up. Herein we review the current state of knowledge about the allergen profilin and its implications in the diagnosis and treatment of allergic diseases. We conclude that, although its role in triggering allergic symptoms is still controversial, profilin is undoubtedly a relevant allergen. As a pan-allergen, profilin is associated with multiple pollen sensitization and pollen-food-latex syndromes that the allergist has to be aware of in order to accomplish an accurate diagnosis and successful treatment of allergic diseases. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Lipid transfer protein (LTP), the most frequent cause of primary food allergy in Italy, is a cross-reacting plant pan-allergen. Markers able to predict whether a patient sensitized to a certain food but not yet clinically allergic will develop allergy would be extremely helpful. Objective: It was the aim of this study to investigate the relevance of IgE levels to some plant foods other than Rosaceae as predictors of either local or systemic allergic reaction in LTP-allergic subjects. Methods: One hundred (40 males, 60 females , mean age 29 years) peach-allergic patients monosensitized to LTP seen at 14 Italian centres in 2009 were studied. Walnut, hazelnut, peanut, tomato, rice and/or maize allergy was ascertained by interview and confirmed by positive skin prick test. IgE levels to these foods and to rPru p 3 were measured. Results: Higher levels of IgE to Pru p 3 were associated with a higher prevalence of allergy to hazelnut, peanut and walnut. For all study foods, except rice, median IgE levels in allergic subjects significantly exceeded those in tolerant subjects, though within single allergic groups, the differences between patients reporting systemic or local (oral) symptoms were not significant. Ninety-five percent cut-off IgE levels predictive of clinical allergy were established for study foods although the marked overlaps between allergic and tolerant subjects made them of limited usefulness. Conclusion: Specific IgE levels are only partially predictive of clinical allergy. The reasons why some individuals showing low specific IgE levels develop clinical allergy whereas others showing high IgE levels do not, despite similar exposure to the allergen, remain unclear. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Allergy to taxonomically related species is a common phenomenon caused by the same immunological receptor cross-reacting to homologous allergens from different species. Knowledge of patterns of cross-reactivity is crucial for the selection of optimal products for diagnosis and for specific immunotherapy. The objective of this study was to investigate patterns of serum IgE cross-reactivity towards pollens from various grass species. Methods: With grass group 1 allergens as the representative group, amino acid sequence alignment, structural modelling and comparison of 3D surface characteristics were performed to exemplify the molecular basis of IgE cross-reactivity. IgE binding to extracts from ten different grass species was determined (total number of data pairs >19,000), and IgE inhibition experiments using Phleum pratense were performed. Results: Analysis of surface topography for group 1 grass allergens demonstrated ample space for IgE binding epitopes in surface areas conserved among Pooideae grasses. Significant correlation was observed between the serum IgE response to P. pratense extract and extracts from the other Pooideae grasses analyzed. P. pratense extract was demonstrated to inhibit the binding of IgE to the allergens in all of the extracts included in the investigation, indicating patient IgE to be primarily directed towards common epitopes. Conclusion: Extensive IgE cross-reactivity was observed towards the allergens of the Pooideae grasses, meaning that the immune system does not appear to distinguish based on the IgE level between the different species of this subfamily. The data suggest equal effect upon use of any of the Pooideae species for diagnostic as well as therapeutic purposes. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Volatile monoisocyanates are formed through thermal degradation when products containing polyurethane are heated. Repeated exposure to diisocyanates, such as toluene diisocyanate (TDI) are a well-known cause of occupational asthma. However, although monoisocyanates are abundant in occupational settings, there are few data concerning their ability to provoke immune reactions and asthma. We compared immune reactivity and respiratory disease following single or repeated inhalation exposures to the monoisocyanates methyl isocyanate (MIC) and isocyanic acid (ICA) with the effects of TDI. Methods:Isocyanates were administrated either as single vapor exposures or as repeated intranasal instillations in rats. Adverse health effects were monitored by analyzing airway inflammation, respiratory function and weight gain. Immune reactivity caused by repeated exposures was studied by analysis of isocyanate-specific antibodies and airway infiltration of immune competent cells. Results: Repeated exposures to TDI induced airway infiltration of neutrophils and lymphocytes, while neither MIC nor ICA provoked a detectable inflammatory response. Antibodies against isocyanate-albumin conjugates were detected in serum after both exposures to TDI and MIC, but not to ICA. TDI-exposed rats also displayed IgG antibodies against MIC-albumin conjugates. Even though MIC did not induce airway inflammation, single exposure provoked an increase in airway resistance and repeated exposures caused weight loss similar to that of TDI. Conclusions: Airway exposure to TDI produces an antibody response not only against TDI but also against MIC-protein conjugates. This indicates that immune reactivity against abundant monoisocyanates in occupational environments can occur in individuals pre-sensitized with low abundance but highly sensitizing diisocyanates. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: The silkworm, Bombyx mori, is an important insect in the textile industry and its pupa are used in Chinese cuisine and traditional Chinese medicine. The silk, urine and dander of silkworms is often the cause of allergies in sericulture workers and the pupa has been found to be a food allergen in China. Recent studies have focused on reporting cases of silkworm allergies, but only a few studies have addressed the specific allergens present in the B. mori silkworm. Methods: We collected sera from 10 patients with a positive skin prick test to silkworm crude extract (SCE) and analyzed these samples by Western blot and ELISA. The cDNA of arginine kinase from the B. mori silkworm was also cloned and expressed in high yield in Escherichia coli. Allergenicity and cross-allergenicity of the recombinant B. mori arginine kinase (rBmAK) were investigated by ELISA inhibition assay. Results: Collected sera all reacted to a 42-kDa protein in a Western blot with SCE as the antigen. Preincubation of sera with rBmAK eliminated the reactivity of the patients’ sera to this 42-kDa band. All patient sera also exhibited positive reactivity to SCE in an ELISA assay. BmAK also demonstrated cross-reactivity with a recombinant AK from cockroach. Conclusion: Arginine kinase from the B. mori silkworm is a major allergen and crossreacts with cockroach AK. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Examination of IgE cross-reactivity among nuts has been limited to in vitro experiments. Cross-reactivity studies of nuts at the T cell level are difficult to interpret because of the inability to determine which cellular responses are from a true sensitization and which are due to cross-reactivity. Using a mouse model in which the sensitizing nuts are controlled may provide novel methods to investigate in vivo and T cell cross-reactivity. Methods: C3H/HeJ mice were sensitized by intraperitoneal injection of cashew alone (monosensitized mice), or cashew plus walnut, utilizing alum as an adjuvant. Both groups underwent challenges to cashew, walnut and peanut, with subsequent monitoring of anaphylactic reactions. Anaphylactic antibodies were quantified by ELISA, and protein allergens were identified by Western blotting. Cellular responses were studied via splenocyte proliferation assay and measurement of secreted cytokines. Results: The monosensitized mice reacted to cashew and walnut during challenges, with significantly weaker reactions induced on challenge with peanut. Cross-reactive IgE to walnut and peanut were detected by ELISA, and the cross-reactive allergens were identified as vicilin proteins. In cellular assays, splenocytes from the monosensitized mice proliferated and produced IL-4 and IL-5 in response to cashew, walnut and peanut. The cashew- plus walnut-sensitized mice experienced stronger clinical reactions to walnut, recognized additional walnut allergens and secreted significantly more IL-4 and IL-5 in walnut-stimulated splenocyte assays compared to the monosensitized mice. Conclusions: Cross-reactivity in vivo was found between cashew and walnut, while cross-reactivity among cashew, walnut and peanut was demonstrated at the T cell level. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Der p 5 was reported as an important allergen in Dermatophagoides pteronyssinus, which is particularly recognized by patients suffering from asthma. The aim of this study was to produce, by recombinant DNA technology, a folded Der p 5 allergen for diagnostic, therapeutic and preventive purposes. Methods: Der p 5-encoding cDNA was isolated from a λgt11 D. pteronyssinus expression cDNA library and expressed in Escherichia coli. rDer p 5 was purified to homogeneity and characterized by mass spectroscopy and circular dichroism. IgE reactivity was tested with sera from 117 mite-allergic patients and in a basophil histamine release experiment. Der p 5-specific rabbit IgG antibodies were produced for the ultrastructural localization of the allergen in mites by immunogold electron microscopy as well as for cross-reactivity studies. Results: rDer p 5 is a heat-stable protein with predominantly α-helical secondary structure which reacted with IgE from 31% of mite-allergic patients’ sera and showed no relevant cross-reactivity to group 5 allergens from storage mites and tropical mites. rDer p 5-specific rabbit IgG antibodies inhibited mite-allergic patients’ IgE binding to Der p 5 and allowed to localize the allergen in secretory granules of midgut epithelial cells of house dust mites. Conclusions: The described rDer p 5 molecule may be useful for diagnosis and immunotherapy of house dust mite-allergic patients. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Cases of allergy to Cannabis sativa have occasionally been reported, but both the allergenic profile and eventual cross-reactivity pattern remain unknown. Objective: To analyze the allergenic profile of a population of patients from Spain sensitized to C. sativa and to characterize the C. sativa leaf extract. Methods: A total of 32 subjects were enrolled in the study: group A, 10 individuals sensitized to tomato, reporting reactions by contact or inhalation to Cannabis; group B, 14 individuals sensitized to tomato, without reactions to Cannabis; group C, 8 individuals not sensitized to tomato and without reactions to Cannabis. Sensitivity to Cannabis, tomato and peach peel, Platanus hybrida and Artemisia vulgaris pollen extracts was measured by skin tests and specific IgE. Individual immunoblots and inhibition experiments with a pool of sera were conducted. Results: All tomato-sensitized subjects (and 1 negative) had positive skin tests to C. sativa leaves and hashish. Specific IgE to C. sativa and peach peel was more common than to tomato. Immunoblot experiments showed 2 prominent bands of 10 and 14 kDa and 2 weakly recognized bands of 30 and 45 kDa. Tomato, peach and A. vulgaris extracts inhibited most of the bands present in C. sativa. P. hybrida inhibited only the high-molecular-weight bands. Conclusion: Sensitization to C. sativa with or without symptoms is frequent among patients in Spain sensitized to tomato. C. sativa leaves are a potential allergenic source and their allergens may cross-react with other allergenic sources from plants (fruit peels and pollen). Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Birch pollen-specific immunotherapy (SIT) decreases allergy to foods containing birch pollen-homologous allergens. Cross-reactivity was also observed between plane tree pollen and some vegetable foods. Objective: The aim of this study was to evaluate the outgrowing of food allergy by patients suffering from vegetable food allergy associated with plane tree pollinosis (rhinoconjunctivitis and/or asthma) during plane tree pollen SIT. Methods: An observational and prospective study was conducted in 16 adult patients suffering from vegetable food allergy (hazelnut, walnut, lettuce, peach and cherry) and from plane tree pollinosis receiving plane tree pollen SIT for 1 year. Open oral challenges with the implicated food were performed before and after SIT. Blood samples were drawn for measurement of pollen- and food-specific IgE and IgG4 before and after treatment. Results: Plane tree SIT resulted in a significant decrease in food allergy, since the mean food quantity provoking objective symptoms increased from 2.19 to 13.74 g (p < 0.05), and 6 of the 11 patients tolerated the highest level (25 g) of the challenged food after plane tree SIT. Laboratory data also showed a decrease in IgE levels and an increase in IgG4 levels after immunotherapy. Conclusion: SIT with plane tree pollen has a positive impact on food allergy in plane tree pollen-allergic subjects. [ABSTRACT FROM AUTHOR]

Background: Grape allergy is considered rare; grape lipid transfer protein (LTP; Vit v 1), an endochitinase and a thaumatin-like protein (TLP) have been reported as grape allergens. A considerable number of patients have referred to our department for severe reactions to grapes, and several IgE binding proteins were detected. Objectives: The aim of this study was to identify and characterise the allergens involved in severe allergic reactions to grapes and describe the population in which they occur. Methods: Patients with reported severe allergic reactions to grapes (n = 37) are described. Grape allergens were purified/fractionated by a combination of chromatographic techniques, identified by proteomic analysis and biochemically characterised. Immunoreactivity was assessed by blot (inhibitions) and RAST (inhibitions), and skin prick tests were performed with the isolated allergens. Results: All subjects were polyallergic, sensitised and reactive to several additional foods and pollen. All patients were sensitised to grape LTP. A 28-kDa expansin, a 37.5-kDa polygalacturonase-inhibiting protein, a 39-kDa β-1,3-glucanase and a 60-kDa protein were identified as minor grape allergens. Endochitinase and TLP did not play a role. Inhibition experiments revealed the possible cross-reactive role of LTP for clinical sensitivities to other LTP-containing plant foods, but also the involvement of cross-reactive carbohydrate determinants of minor allergens in IgE cross-reactivity. Conclusions: LTP is the major grape allergen, while additional minor allergens may contribute to clinical reactivity. Severe grape allergy presents in atopic patients who frequently react to other LTP-containing, plant-derived foods. The ‘LTP syndrome’ is the appropriate term to describe this condition. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Trees of the family Oleaceae are important allergen sources, with a strongly varying geographic distribution. For example, olive pollen is an important allergen source in Mediterranean countries, whereas ash pollen dominates in Northern and Central Europe and North America. The aim of this study was to compare the profiles of olive and ash pollen allergens and to study the degree of cross-reactivity using populations of allergic patients selectively exposed to olive or ash pollen. Methods: Olive and ash pollen extracts were analyzed by IgE immunoblotting using sera from Spanish patients highly exposed to olive pollen and Austrian patients without olive but ash pollen exposure. IgE cross-reactivity was studied by qualitative immunoblot inhibition assays and semiquantitative ELISA inhibitions using olive, ash, birch, mugwort, timothy grass pollen extracts and the major olive pollen allergen, Ole e 1. Results: Spanish and Austrian patients exhibited an almost identical IgE-binding profile to olive and ash pollen allergens, with major reactivity directed against Ole e 1, and its homologous ash counterpart, Fra e 1. IgE inhibition experiments demonstrated extensive cross-reactivity between olive and ash pollen allergens. However, whereas cross-reactions between profilins and calcium-binding allergens also occurred between unrelated plant species, cross-reactivity to Ole e 1 was confined to plants belonging to the Oleaceae. Conclusions: Ole e 1 is a marker allergen for the diagnosis of olive and ash pollen allergy. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Patients sensitized to airborne fungi such as Alternaria alternata and Cladosporium herbarum often also show positive skin prick test results and specific serum IgE antibodies to a yeast, Pityrosporum ovale. We examined whether part of the IgE binding to these fungi is explained by cross-reacting mould and yeast allergens. Methods: Serum samples from 36 patients with positive skin prick test to A. alternata or C. herbarum were analyzed for IgE antibodies to fungal extracts by ELISA and immunoblot analysis. Cross-reactivity between mould and yeast extracts was studied by ELISA and immunoblot inhibition assays. In further analysis, the mannan-containing glycoproteins were removed from the yeast extract by concanavalin A-Sepharose chromatography, and the IgE binding properties of the extracts were compared. Results: SerumIgE reactivity to P. ovale was found in 40% of the mould-sensitized patients. The IgE antibody binding to A. alternata and C. herbarum moulds was partially inhibited by the yeast P. ovale in ELISA and immunoblot inhibition assays. When the glycoproteins were removed from the extract, cross-reactivity was markedly reduced. Conclusion: Part of the IgE binding to mould and yeast allergen extracts is due to cross-reacting glycoproteins. False-positive IgE and skin prick test results should be taken into account in the diagnosis of mould allergy. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background:Holoptelea integrifolia and Parietaria judaica belong to the family Urticaceae, but are geographically distantly located. H. integrifolia is an important pollen allergen of India and sensitizes almost 10% of the atopic population in Delhi. P. judaica, on the other hand, is a very dominant pollen allergen of the Mediterranean region, sensitizing almost 80% of the allergic population. Since both these important pollen allergens belong to the family Urticaceae, the objective of the present study was to assess cross-reactivity between these two pollen allergens from different geographical regions. Methods: Cross-reactivity between these two pollen allergens was assessed on the basis of skin prick tests and ELISA, ELISA inhibition and immunoblot inhibition studies. Results: Out of 44 atopic Indian patients skin prick tested with H. integrifolia extract, 34% were found to be sensitized. All the patients sensitized to H. integrifolia also showed varying degrees of skin positivity to P. judaica pollen extract. ELISA and ELISA inhibition studies suggested strong cross-reactivity between H. integrifolia and P. judaica pollen. Immunoblot inhibition studies revealed that 14-, 16-, 28-, 38-, 42- and 46-kDa proteins are the cross-reactive proteins in H. integrifolia and P. judaica. However, Par j 1, the major allergen of P. judaica, is absent in H. integrifolia pollen. Conclusion:H. integrifolia and P. judaica pollens share cross-reactive as well as unique epitopes. The major allergen of P. judaica, Par j 1, seems to be absent in H. integrifolia pollen allergen. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Ingestion of snails can induce strong asthmatic or anaphylactic responses, mainly in house-dust-mite-sensitized patients. The aim of this study was to identify the Helix aspersa (Hel a), Theba pisana (The p) and Otala lactea (Ota l) allergens and the extent of their cross-reactivity with the Dermatophagoides pteronyssinus (Der p) mite. Patients and Methods: In 60 atopicpatients, skin prick tests (SPT) to snail and D. pteronyssinus, total and specific IgE, specific IgE immunoblots, RAST and immunoblot inhibition assays were performed. Results: Mean total IgE was >1,000 kU/l. Mean specific IgE (class 6 for Der p and class 2 for Hel a) SPT were positive in 44 patients for snail and in 56 for mite. Isoelectric focusing (IEF) and SDS-PAGE followed by immunoblotting of H. aspersa extract enabled the identification of 27 and 20 allergens, respectively. Myosin heavy chains from snails (molecular weight >208 kDa) disclosed two major allergens. Hel a and Der p RAST were strongly inhibited by their homologous extracts, with Hel a RAST being inhibited by the Der p extract to a much greater extent (72.6%) than the inverse (5.6%). A complete inhibition of the immunoblots by their homologous extract was obtained. However, Hel a extract did not inhibit Der p IEF separated recognition. On the other hand, mite extract extensively inhibited snail immunoblots from both IEF and SDS-PAGE separations. Immune detection on chicken, pig, rabbit, cow and horse myosins did not reveal any IgE cross recognition with snail. Conclusions: In most cases of snail allergy, mite appeared to be the sensitizing agent. Nevertheless, snails may also be able to induce sensitization by themselves. This hypothesis is supported by the finding of specific IgE to Hel a in 2 patients who did not show specific IgE to Der p, and one of them was suffering from asthma after snail ingestion. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Profilins are conserved and ubiquitous plant and animal proteins. We wanted to discover whether the T-cell response to conserved epitopes on birch and grass profilins could account for cross-allergenicity in subjects allergic to these two pollens. Methods: Thirty-one patients allergic to grass and birch were recruited for the study. Grass and birch reactive T lymphocytes were studied by measuring proliferation to birch and grass allergen, respectively, followed by Vβ T-cell receptor family-specific polymerase chain reaction and heteroduplex analysis. T-cell clones were derived from patients with cross-proliferating T cells. Results: In 25 of 31 subjects the T-cell response to grass was quite distinct from that to birch. In contrast, in 6 of 31 individuals grass T cells cross-proliferated to birch and this was reproduced in 4 patients by birch profilin. CD4 Th2 cell clones were derived which promiscuously recognized homologously conserved regions on birch and grass profilins. Conclusion: We conclude that a functionally relevant T-cell response to conserved regions of panallergens underlie cross-allergenicity in a subset of allergic patients. These results suggest that a reciprocal modulation of the response to one sensitizing allergen can occur following natural exposure to or immunotherapy with another allergen. These results have relevance in the management of patients with multiple allergies. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Tree pollens are among the most important allergen sources. Allergic cross-reactivity to pollens of trees from various plant orders has so far been classified according to botanical relationships. In this context, cross-reactivities to pollens of trees of the Fagales order (birch, alder, hazel, hornbeam, oak, chestnut), fruits and vegetables, between pollens of the Scrophulariales (olive, ash, plantain, privet, lilac) and pollens of the Coniferales (cedar, cypress, pine) are well established. The application of molecular biology methods for allergen characterization has revealed the molecular nature of many important tree pollen allergens. We review the spectrum of tree pollen allergens and propose a classification of tree pollen and related allergies based on major allergen molecules instead of botanical relationships among the allergenic sources. This molecular classification suggests the major birch pollen allergen, Bet v 1 as a marker for Fagales pollen and related plant food allergies, the major olive pollen allergen, Ole e 1, as a possible marker for Scrophulariales pollen allergy and the cedar allergens, Cry j 1 and Cry j 2, as potential markers for allergy to Coniferales pollens. We exemplify for Fagales pollen allergy and Bet v 1 that major marker allergens are diagnostic tools to determine the disease-eliciting allergen source. Information obtained by diagnostic testing with marker allergens will be important for the appropriate selection of patients for allergen-specific forms of therapy. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Recombinant proteins from Pichia pastoris need to be fully evaluated before used as diagnostic tools. Objective: The objective of this study was to investigate whether glycosylation by P. pastoris interferes with the specificity of diagnostic tests. Methods: An autoantigen involved in Wegener’s disease (protease 3) and 2 major inhalant allergens from grass pollen (Dac g 5) and house dust mite (Der p 1) were produced as recombinant molecules in P. pastoris. O-linked glycans on Dac g 5 were characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The immune reactivity of the recombinant proteins was compared to that of their natural counterparts by ELISA and a radio-allergosorbent test (RAST) as well as by ELISA and RAST inhibition. Results: In contrast to the non-glycosylated natural allergen, recombinant Dac g 5 was shown to carry at least 2 small mannose-containing O-glycans. We showed that both these O-glycans and the N-linked glycans on recombinant protease 3 and recombinant Der p 1 were recognized in ELISA by IgG antibodies in sera of healthy individuals. These IgG responses were closely correlated. The natural autoantigen and allergens were not recognized by IgG antibodies from healthy subjects. The carbohydrate nature of the epitopes recognized by IgG on the recombinant proteins was confirmed by inhibition studies with mannose and yeast mannan. IgE recognition of yeast glycans was observed in 2 out of 9 positive sera from patients with allergic bronchopulmonary aspergillosis. Conclusion: Production of recombinant molecules in yeast (or moulds) can introduce IgG-binding glycans that negatively affect the specificity of diagnostic tests. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Cypress pollen allergy is an important cause of rhinoconjunctivitis and asthma in Mediterranean countries. Cypress allergenic extracts are difficult to produce since they have low protein and high carbohydrate content, thus accurate standardization of them is essential to guarantee their quality. The aim of this study is to develop a sandwich ELISA for the quantification of Cup a 1, the major allergen of cypress (Cupressus arizonica) pollen extract. Methods: Monoclonal antibodies directed to purified Cup a 1 were produced. Two of them (9C7 as capture antibody and 3D2 as the tracer) were selected to develop a quantitative sandwich ELISA. This ELISA was subsequently evaluated and compared with other techniques. Results: The described ELISA is very sensitive with a detection limit of 8.7 ng/ml and a practical working range of 62.5–1,000 ng/ml. The assay is also highly reproducible with intra-assay and interassay coefficients of variation of less than 10%. The purified Cup a 1, used as standard, presents pectate lyase enzymatic activity. The assay also detected Cup a 1-like proteins in pollen from other Cupressaceae. A good correlation was obtained between Cup a 1 content of 12 C. arizonica pollen extracts and their IgE-binding activity. Conclusions: The described Cup a 1 ELISA is sensitive, specific and reproducible and can be used for the quantification of Cup a 1 in C. arizonica and other related pollen extracts. It also provides a reliable indication of the allergenic activity of the whole cypress pollen extract. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: ‘Latex-fruit syndrome’ has been well documented. A prevalence of latex allergy among medical workers of 6.8–8.6% had been reported in Taiwan. However, there has been no study to determine the importance and type of fruit hypersensitivity in latex-allergic patients in Taiwan. This study aimed to identify the allergenic components of Indian jujube (Zizyphus mauritiana) and characterize the cross-reactivity of specific IgE antibodies to latex allergen. Methods: Crude extracts were prepared from Indian jujube and from ammoniated natural rubber latex, and six medical workers and one patient with a history of fruit allergy underwent skin testing with routine allergens, latex, Indian jujube and other fruits. Sera from two Indian jujube skin test-positive latex-allergic subjects were used for allergen-specific IgE, immunoblotting, immunoblot inhibition and enzyme-linked immunosorbent assay (ELISA) inhibition studies. Results: Both patients had positive skin test responses and specific IgE assays to Indian jujube and latex extracts. Immunoblotting revealed that IgE from both subjects bound to a 42-kD latex protein and a 42-kD Indian jujube protein. In addition, IgE from one subject bound to a 30-kD Indian jujube protein. Preincubation of atopic sera with Indian jujube or latex extract demonstrated absent and/or marked inhibition of IgE binding. Moreover, anti-Indian jujube protein antibody-based ELISA was able to detect latex extracts. Conclusions: Our results add to findings regarding the ‘latex-fruit syndrome’ described in the literature, and further study of the cross-reacting allergens identified in Indian jujube may help to elucidate the mechanisms underlying this syndrome. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background:Epicoccum purpurascens (formerly nigrum) (EP), is a ubiquitous saprophytic mould found both indoors and outdoors. Several studies have reported sensitization to EP in 5–7 % of different populations worldwide. The diagnosis of mould allergy requires a standardized fungal extract that contains all its important allergenic proteins. The crude allergen extract from EP was standardized earlier, however none of its allergens have been purified. Methods: A major allergen from spore-mycelia extract of EP was purified using concanavalin A (Con A) Sepharose chromatography, gel filtration and electro-elution. The allergen isolated was characterized for its IgE-binding ability and cross-reactivity with five well-known allergenic fungi by ELISA and immunoblot. Results: A 33.5-kD glycoprotein allergen of EP, Epi p 1, was purified to homogeneity. All the EP allergic patients’ sera tested recognized this protein. Periodate modification of Epi p 1 showed partial loss in IgE binding while proteinase K treatment caused complete loss in binding to IgE. Dose-dependent inhibition in binding of rabbit anti Epi p 1 antibodies was obtained with Epi p 1, Aspergillus fumigatus, Alternaria alternata, Curvularia lunata, Cladosporium herbarum and Fusarium solani in ELISA. Rabbit antibodies to all the above five fungi recognized Epi p 1 in immunoblot, confirming that Epi p 1 shares common epitopes with the fungi tested. Conclusion: A major glycoprotein allergen of 33.5 kD was purified from EP which cross-reacts with other fungi. Hence this glycoprotein can be exploited to reduce the panel of allergen extracts used for therapy of mould allergy. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: In patients showing multiple reactivity to seasonal airborne allergens, a skin prick test (SPT) with Parietaria pollen scores frequently negative, suggesting that profilin from Parietaria might not share IgE-binding epitopes with profilin from botanically unrelated airborne allergens. This study investigated the immunologic cross-reactivity between profilins from Parietaria , grass and birch pollen. Methods: 36 patients hypersensitive to birch profilin, Bet v 2, underwent SPT with Parietaria , and IgE to both whole Parietaria pollen and Phleum profilin were sought in their sera by ELISA. In ELISA inhibition studies, IgE reactivity to Phleum profilin was measured before and after absorption of sera from Parietaria reactors with both whole Parietaria pollen extract, and Par j 1/Par j 2 fraction. Further, their IgE reactivity to whole Parietaria pollen was measured before and after absorption with the Par j 1/Par j 2 fraction. Results: All sera showed IgE reactivity to Phleum profilin. Only 14/36 (39%) patients had a positive SPT to Parietaria and 17/36 (47%) showed IgE to Parietaria . Absorption of sera from Parietaria reactors with whole Parietaria extract caused a marked reduction in IgE reactivity to grass profilin; in contrast, absorption of sera with the Par j 1/Par j 2 fraction did not exert any inhibitory effect on IgE reactivity to grass profilin. Absorption of sera with the Par j 1/Par j 2 fraction markedly reduced IgE reactivity to whole Parietaria extract in 8/9 cases. Conclusion: Less than 50% of patients sensitized to birch and grass profilin cross-react to Parietaria profilin. In most cases, cross-reactors are hypersensitive to major, specific Parietaria allergens as well. This findings may be of practical relevance when the prescription of specific immunotherapy is considered. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: A few cases of IgE-mediated chicory allergy with oral, cutaneous, and/or respiratory symptoms are reported. We present 4 patients with inhalant birch pollen allergy and oral allergy syndrome to chicory. IgE-binding proteins in chicory and cross-reactivity with birch pollen were studied. Methods: Chicory extract was prepared and immunoblotting was used to study IgE reactivity and cross-reactions with birch pollen. Results: The pattern of IgE binding to chicory was variable among the patients, with protein bands recognized at 18, 21, 40, 52 and 71 kD. Bet v 1-like proteins were detected in chicory by monoclonal antibody binding. Chicory-birch pollen cross-reactivity, as studied in 2 patients from whom enough serum was available, could be demonstrated but did not involve the Bet v 1 protein family. In one of these cases, a 51-kD protein of birch pollen was found to be responsible for cross-reactivity. Conclusions: Chicory should be added to the list of foods that can cross-react with birch pollen and cause the birch pollen-associated oral allergy syndrome.Copyright © 2003 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: One of the latex allergens, Hev b 2, has β-1,3-glucanase activity. The entire sequence of this allergen is already known. There is one potential N-glycosylation site in this molecule ([sup 27] Asn). Heterogeneous glycosylation of this Asn residue could be a source of the multiplicity of natural Hev b 2. Possible participation of the carbohydrate epitopes of latex β-1,3-glucanase isoenzymes in their IgE-binding capacity and cross-reactivity was investigated in this study. Methods: β-1,3-Glucanase isoenzymes were separated based on their affinities for concanavalin A. IgE-binding capacity and cross-reactivity were examined by immunoblotting and enzyme-linked immunosorbent assay (ELISA). Sequence heterogeneity among the isoenzymes was probed by peptide mass mapping after lysyl endopeptidase digestion. To clarify the relation to Hev b 2, N-terminal sequencing was performed on a fragmented peptide common to the separated isoenzymes. Results: Basic β-1,3-glucanase was subdivided into two glycosylated isoenzymes (GI and GII) and one non-glycosylated isoenzyme (GIII). IgE antibodies in latex-positive sera chiefly recognized the glycosylated isoenzymes. Inhibition ELISA supported the significance of the carbohydrate epitopes for the IgE recognition and cross-reactivity. However, non-glycosylated GIII, as well as GI and GII, produced positive results in a skin prick test. The three β-1,3-glucanase isoenzymes shared a partial sequence in common with Hev b 2. Conclusions: Our results suggest that the carbohydrate epitopes in Hev b 2 homologues are relevant to an in vitro diagnosis of latex allergy and the accompanying cross-reactivity. Carbohydrate epitopes do not necessarily provoke allergic symptoms. Therefore, the actual allergenicity of Hev b 2 and its homologues should be carefully evaluated not only by in vitro IgE tests but also by in vivo tests.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Shrimp may cross-react with other crustaceans and mollusks and nonedible arthropods such as insects (cockroach and chironomids), arachnids (house dust mites) and even nematodes. Since the muscle protein tropomyosin has been implicated as a possible cross-reacting allergen, this study characterized the IgE-binding epitopes in shrimp tropomyosin, Pen a 1, that cross-react with other allergenic invertebrate tropomyosins in house dust mites (Der p 10, Der f 10) and cockroaches (Per a 7). Pen a 1-reactive sera from shrimp-allergic subjects were used to evaluate the effect on IgE binding of different amino acid substitutions in Pen a 1 epitopes based on homologous sequences in Per a 7 and Der p 10/Der f 10. Methods: Peptides were synthesized spanning the length of Pen a 1 IgE-binding epitopes and amino acid substitutions were performed based on homologous amino acid sequences from Per a 7 and Der p 10/Der f 10. Results: 7/8 individually recognized Pen a 1 epitopes (2, 3a, 3b, 4, 5a, 5b and 5c) had an identical amino acid sequence with lobster allergen, Hom a 1, 4/8 (3a, 3b, 4 and 5a) with Der p 10 and Der f 10, and 5/8 (2, 3a, 3b, 4 and 5a) with Per a 7. In addition, even homologous regions of other arthropod tropomyosins that differ in one or more amino acids from the sequences of Pen a 1 epitopes are still recognized by shrimp-allergic IgE antibodies. In total, shrimp-allergic sera recognize 6/8 peptides homologous to Pen a 1 epitopes in Per a 7, 7/8 in Der p 10/Der f 10, and 7/8 epitopes in Hom a 1. Conclusions: The IgE recognition by shrimp-allergic individuals of identified and/or similar amino acid sequences homologous to Pen a 1 epitopes in mite, cockroach and lobster tropomyosins are the basis of the in vitro cross-reactivity among invertebrate species. Based on amino acid sequence similarity and epitope reactivity, lobster tropomyosin has the strongest and cockroach the least cross-reactivity with shrimp. The clinical relevance of these cross-reactivities in developing allergic reactions to different arthropods needs to be determined.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Almond proteins can cause severe anaphylactic reactions in susceptible individuals. The aim of this study was the identification of IgE-binding proteins in almonds and the characterisation of these proteins by N-terminal sequencing. Methods: Five sera were selected from individuals with a positive reaction to food challenge. Sodium dodecylsulphate-polyacrylamide gel electrophoresis and immunoblotting were performed on almond seed proteins. Purified IgE-binding proteins were tested for immunoblot inhibition with sera pre-incubated with extracts of hazelnut and walnut. Results: N-terminal sequences of the 12-, 30- and 45-kD proteins were obtained. The 45- and 30-kD proteins shared the same N terminus, with 60% homology to the conglutin γ heavy chain from lupine seed (Lupinus albus) and to basic 7S globulin from soybean (Glycine max). The sequences of the N-terminal 12-kD protein and of an internal peptide obtained by endoproteinase digestion showed good homology to 2S albumin from English walnut (Jug r 1). Immunoblot inhibition experiments were performed and IgE binding to almond 2S albumin and conglutin γ was detected in the presence of cross-reacting walnut or hazelnut antigens. Conclusions: Two IgE-binding almond proteins were N-terminally sequenced and identified as almond 2S albumin and conglutin γ. Localisation and conservation of IgE binding in a 6-kD peptide obtained by endoproteinase digestion of 2S albumin was shown.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Gastropod consumption is quite frequent in the Mediterranean countries and cross-reactivities with crustaceans have been described, but the mechanism of this allergenic cross-reactivity has not been studied in detail. This study aimed to produce recombinant Helix aspersa (brown garden snail) tropomyosin and investigate its implication for cross-reactivity among invertebrates. Methods: A tropomyosin-specific cDNA encoding H. aspersa tropomyosin was synthetized, and recombinant allergen was overexpressed in Escherichia coli as nonfusion protein. IgE-binding reactivity was studied by immunoblotting and immunoblot inhibition experiments with sera from snail-allergic patients. Results: Cloned brown garden snail tropomyosin shares high homology with other edible mollusk tropomyosins (84–69% identity) as well as with those from arthropods (65–62%), and less homology with vertebrate ones (56% identity). Tropomyosin reacted with 18% of the sera from patients with snail allergy. Inhibition experiments, using natural and recombinant tropomyosins, showed different degrees of cross-reactivity between invertebrate tropomyosins. Sera from snail-allergic subjects recognized tropomyosins in both mollusks and crustacean extracts. Conclusions: Tropomyosin represents a minor allergen in snail extracts, but it is clearly involved in invertebrate cross-reactivity.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Lipid transfer proteins (LTPs) are major allergens of Rosaceae fruits in the Mediterranean area. IgE-cross-reactivity has been demonstrated in vitro among LTPs from peach, apple, chestnut and Artemisia pollen. The aim of this study was to evaluate the reactivity to LTPs from peach, apple, chestnut and Artemisia pollen by means of skin prick tests (SPTs). Methods: Forty-seven patients allergic to peach (peach group), 20 patients sensitized to Artemisia pollen with no food allergies (Artemisia group), and 12 control subjects were skin tested with fresh peach, as well as with whole extracts and purified LTPs of peach, apple, chestnut and Artemisia pollen. Results: The rates of positive SPTs for peach, apple, chestnut and Artemisia LTPs were, respectively, 91, 77, 23, and 36% in the peach group, and 30, 5, 15 and 40% in the Artemisia group. No response was observed in the control subjects. SPTs with peach LTP strongly correlated with SPTs conducted with fresh peach. In the peach group, the most frequent pattern of reactivity to LTPs was the combination peach-apple (45%), followed by peach-apple-Artemisia-chestnut (21%). Significant correlations were found between peach and apple LTPs, and between Artemisia and chestnut LTPs. Positive SPTs to chestnut LTP were only observed in patients with positive SPTs to Artemisia LTP. All the patients with positive case histories to chestnut reacted to chestnut LTP. Conclusions: LTPs are plant panallergens with different patterns of cross-reactivity. They are major allergens of Rosaceae fruits and seem to be involved in allergic reactions to unrelated foodstuffs such as chestnut, probably through sensitization to the cross-reactive Artemisia LTP. Rosaceae LTPs could be useful tools for in vivo diagnosis of Rosaceae fruit allergy.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background:Curvularia lunata is an important inhalant allergen. The present study was undertaken to investigate the shared IgG- and IgE-binding components among seven Curvularia species prevalent in the aerospora. Methods: Seven different Curvularia species were grown in a semisynthetic medium for 13 days. The extracts were analyzed by SDS-PAGE, immunoblot and ELISA/immunoblot inhibition using sera from C. lunata-positive patients and anti-C. lunata rabbit serum. Results: Different Curvularia species showed 11–19 protein bands on SDS-PAGE. Proteins of 12, 20, 31, 45, 53, 78 and 97 kD were present in all the species. Eight out of 98 nasobronchial patients exhibited positive skin tests to C. lunata and to at least five Curvularia species. ELISA using these sera showed IgE binding with Curvularia species. Immunoblot using pooled anti-C. lunata sera from patients showed 5–12 allergenic proteins. Proteins of 12, 31, 45, 53 and 78 kD showed IgE binding in Curvularia species. Antibodies against C. lunata detected 6–14 antigenic proteins on immunoblot. Proteins of 31, 45 and 53 kD showed IgG binding in all the species. Proteins of 31 and 53 kD showed complete IgE/IgG binding inhibition. IgE/IgG ELISA inhibition showed dose-dependent inhibition in Curvularia species. C. lunata extract required 0.17 and 0.11 μg of protein for 50% IgE and IgG inhibition, respectively. C. clavata and C. pallescens required 10 times more protein to exhibit the same inhibition and other species required similar protein levels as those required by C. lunata.Conclusions: A high degree of cross-reactivity was observed between C. lunata and the six other Curvularia species tested. C. lunata and C. senegalensis shared maximum allergenic and antigenic components.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Plant profilins are important pan-allergens. They are responsible for a significant percentage of pollen-related allergies. Limited information is available about their involvement in the latex-fruit syndrome and the cross-reactivities between latex and pollen. We aimed to clone and express the Hevea brasiliensis latex profilin to investigate its allergological significance and serological cross-reactivities to profilins from plant foods and pollens. Methods: A DNA complementary to messenger RNA (cDNA) coding for the Hevea latex profilin, Hev b 8, was amplified by polymerase chain reaction from latex RNA. Recombinant (r)Hev b 8 was produced in Escherichia coli and used to screen sera from 50 latex- allergic health care workers (HCWs) with well-documented histories of food and pollen allergy and 34 latex-allergic spina bifida (SB) patients. The cross-reactivity of natural Hev b 8 and rHev b 8 with other plant profilins was determined by ELISA inhibition assays. A three-dimensional homology model of Hev b 8 was constructed based on known profilin structures. Results: The cDNA of Hev b 8 encoded a protein of 131 amino acids with a predicted molecular mass of 14 kD. Twelve of the 50 HCWs and 2 of the 34 SB patients were sensitized to Hev b 8. All Hev b 8-sensitized patients showed allergic symptoms to pollen or plant foods. Cross-reactivities between profilins of latex, pollen and plant food were illustrated by their ability to inhibit IgE binding to rHev b 8. Homology modeling of Hev b 8 yielded a structure highly similar to Bet v 2, the birch pollen profilin, with the most distinct differences located at the N-terminus. Conclusions: We conclude that primary sensitization to latex profilin in the majority of cases takes place via pollen or food profilins. Additionally, pollinosis and food-allergic patients with profilin-specific IgE can be at risk of developing latex allergy.Copyright © 2001 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Experiments were aimed to test the cross-reactivity of immune Th1 cells that mediate contact hypersensitivity (CHS) or inflammatory bowel disease (IBD) to TNP in the mouse. Methods: CBA/J mice were immunized either epicutaneously or intrarectally with TNP and after appropriate time intervals were challenged with antigen in a crossed manner. The CHS reaction was measured by the ear swelling test. IBD was quantified by increase of colon weight and myeloperoxidase level. Both reactions were confirmed histologically. In passive-transfer experiments, mesenteric lymph node cells of animals sensitized intrarectally and peripheral lymph node and spleen cells of mice immunized epicutaneously were used. In some experiments, before being immunized mice were made either unresponsive to the TNP hapten by induction of suppressor T cells, or resistant to suppression after induction of upregulatory T cells. Results: Irrespective of the mode of sensitization upon appropriate challenge with antigen all mice developed a good CHS reaction as well as significant IBD. This cross-reactivity could be passively transferred by immune cells. In mice in which antigen-specific down- or upregulatory cells were induced before sensitization both CHS and IBD to TNP were modulated accordingly. Conclusion: TNP hapten deposited on skin or on mucosal surfaces induces effector cells that recognize antigen independent of its tissue localization, and produce a local inflammatory reaction. TNP-specific up- and downregulatory cells, shown before to regulate the CHS reaction, similarly modulate the generation and development of hapten-induced IBD.Copyright © 2000 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Double sensitization to honeybee (Apis mellifera) and wasp venom (Vespula spp.) as determined by skin test and measurement of specific IgE is common in hymenoptera sting allergy. Double-sensitized patients have either distinct antibodies for each venom or cross-reacting antibodies that recognize similar or identical epitopes in both venoms. Unfortunately, patients often fail to identify the stinging insect which makes it difficult to distinguish cross-reactors from non cross-reactors. However, for economic reasons as well as for the benefit of the patients, it would be useful to identify complete cross-reactors. Methods: In this study we investigated 24 double-sensitized patients who were candidates for venom immunotherapy. Homologous and heterologous FEIA inhibition was carried out with honeybee (Apis mellifera) and wasp venom (Vespula spp.) preparations from two different providers. The inhibitor concentrations were ranging from 0 to 100 μg protein/ml. Results: Sera of 4 patients were completely cross-reacting for one venom (3 honeybee, 1 wasp), 8 patients were partially cross-reacting and 10 patients were not cross-reacting. Two patients were excluded from the study due to insufficient homologous inhibition. Data from specific IgE measurements, skin test, and clinical history were not useful for the identification of cross-reacting patients. Conclusion: FEIA inhibition is easy to perform and useful for the identification of patients with complete cross-reactivity. In these patients immunotherapy might be restricted to one venom which is beneficial for the patient and cost-effective.Copyright © 2000 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Lipid transfer proteins (LTPs) are small molecules of approximately 10 kD that demonstrate high stability. They have recently been identified as allergens in the Rosaceae subfamilies of the Prunoideae (peach, apricot, plum) and of the Pomoideae (apple). They belong to a family of structurally highly conserved proteins that are also present in non-Rosaceae vegetable foods. Objective: The aim of this study was to investigate the cross-reactivity to non-Rosaceae LTPs, and to study the role of protein stability in allergenicity. Methods: Thirty-eight patients with a positive SPT to Rosaceae fruit extracts enriched for LTP were characterized by interview and SPT. To investigate IgE cross-reactivity between Rosaceae and non-Rosaceae LTPs, RAST and RAST inhibition as well as ELISA and ELISA inhibition were performed, using whole food extracts and purified LTPs. Both purified natural LTPs (peach, carrot and broccoli) and Pichia pastoris recombinant LTPs (carrot and wheat) were included. Pepsin digestion was used to address the role of stability in the allergenicity of LTPs. Results: IgE antibodies to Rosaceae LTPs reacted to a broad range of vegetable foods, including Gramineae (cereals), Leguminosae (peanut), Juglandaceae (walnut), Anacardiaceae (pistachio), Brassicaceae (broccoli), Umbelliferae (carrot, celery), Solanaceae (tomato), Cucurbitaceae (melon), and Actinidiaceae (kiwi). Binding and inhibition studies with purified natural and recombinant LTPs confirmed their role in this cross-reactivity. Many of these cross-reactivities were accompanied by clinical food allergy, frequently including systemic reactions. Antibody binding to LTP was shown to be resistant to pepsin treatment of whole extract or purified LTP. Conclusion: LTP is a pan-allergen with a degree of cross-reactivity comparable to profilin. Due to its extreme resistance to pepsin digestion, LTP is a potentially severe food allergen.Copyright © 2000 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Pollen from oilseed rape (OSR), Brassica napus, an increasingly cultivated oilplant from the Brassicaceae, has been recognized as a potential cause of allergic sensitization. Allergens have been hardly investigated. Methods: We characterized IgE binding proteins in OSR pollen by immunoblot, immunoblot inhibition and specific monoclonal antibodies using sera from 89 patients sensitized to OSR. Results: Two low–molecular–weight allergens of 6/8 kD and 14 kD as well as a high molecular–weight cluster (27–69 kD) comprising six cross–reactive peptides could be identified. The three allergens were recognized by 50, 34 and 80% of patients, respectively. Immunoblot IgE binding to OSR could be totally inhibited by rye pollen and moderately by birch pollen (6/8 and 14 kD) while mugwort had little effect. An anti–profilin–specific monoclonal antibody bound specifically to a 14–kD protein in OSR. Binding to the 6/8–kD rape allergen could be effectively inhibited by rAln g 2, a calcium–binding protein from alder. Periodate treatment led to a significant reduction in IgE binding to the 27 to 69–kD OSR allergens indicating that carbohydrate determinants are involved in IgE binding. OSR proteins were capable to quench IgE binding to timothy grass pollen proteins of ≥60 kD suggesting that grass pollen group 4 allergens cross–react with the 27 to 69–kD cluster in OSR. Conclusions: The data demonstrate that OSR pollen is allergenic and indicate that the identified allergens represent cross–reacting homologues of well–known pollen allergens, i.e. calcium–binding proteins, profilins, and high–molecular–weight glycoproteins. Via cross–reactivity, exposure to OSR pollen may be a prolonging and aggravating factor in underlying birch and grass pollen allergy. [ABSTRACT FROM AUTHOR]

Background: In tropical climates, sensitization to Bloma tropicalis and Dermatophagoides pteronyssinus is high and mainly directed to species–specific allergens. There is some cross–reactivity between extracts of these mites, probably due to the group 5 allergens that have high sequence homology. Objective and Methods: We used the radioallergosorbent test (RAST), RAST inhibition and immunoblotting inhibition experiments to investigate the cross–reactivity between the recombinant allergens BtM and Der p 5, expressed as glutathione S–transferase fusion proteins, to detect the epitopes involved and to analyze the importance of this cross–reactivity. Results: Seventy–nine percent of 48 patients sera were RAST positive to both recombinants, with a strong correlation (r = 0.8, p<0.0001). BtM inhibited 25 and 21.1% of IgE–binding to B. tropicalis and D. pteronyssinus extracts respectively and Der p 5 inhibited 22 and 24% of IgE–binding to D. pteronyssinus and B. tropicalis extracts. Furthermore, BtM inhibited 74.5% of IgE binding to Der p 5 and Der p 5 inhibited 72.4% of IgE–binding to BtM. RAST inhibition with BtM–derived synthetic peptides showed that peptide 4 (residues 35–50) and peptide 5 (residues 46–61) inhibited 37 and 16% of IgE–binding to BtM while peptides 5 and 2 (residues 14–30) were able to inhibit the IgE binding (32 and 28%, respectively) to Der p 5. Conclusion: There is cross–reactivity between BtM and Der p 5, which explains almost all the cross–reactivity between the two mite extracts. This cross–reactivity seems to be related to epitope(s) at the C–terminal segment of these allergens. [ABSTRACT FROM AUTHOR]

Background: Dermatophagoides siboney (Ds) cross–reacted with other mite allergens in mite–allergic patients. The aim of this study was to investigate the cross–reactivity between individual allergens responsible for this cross–reactivity. Methods: The inhibition of IgE binding to Ds allergens was investigated by non–reducing SDS–PAGE and Western blotting. Nitrocellulose membranes were incubated with a pool of sera from mite–sensitive asthmatics, after the addition of serial dilutions of D. farinae (Df), D. pteronyssinus (Dp), D. microceras (Dm), Lepidoglyphus destructor (Ld), Tyrophagus putrescentiae (Tp), Acarus siro (As) and Blomia tropicalis (Bt). N–terminal amino acid sequences and amino acid analysis of the purified major allergens, Der s 1, 2 and 3, were performed after transfer to polyvinylidene difluoride membranes. Results: The inhibition was higher with Df (86%), Dp (54%) and Dm (49%) extracts than with Ld (20%), Tp (11%), As (18%) and Bt (6%). The dose–response inhibition showed a diverse pattern for the individual allergens. Despite the high cross–reactivity between the pyroglyphid mites, some proteins of Ds were less inhibited, e.g. by the Df and Dp 80–kD protein, and by the Dm and Dp 52–, 37–, 30– and 14–kD allergens. The 65–, 62–, 37– and 30–kD proteins were always inhibited more than 50% by all the mite extracts at the maximum concentration used. The 80–, 52–, 43–, 27– and 14–kD proteins cross–reacted to a lesser extent. Individual allergens of Ds were much less inhibited by non–pyroglyphid mites. However, at the highest concentration, Ld also inhibited most of the Ds allergens. All the ten selected allergens were inhibited to some extent by the heterologous mite extracts. The N–terminal sequences of Der s 1, 2 and 3 allergens showed higher homology to Df and Dm than to Dp. The homology of the group 2 allergens was higher than that of the group 1 allergens. Conclusion: The individual allergens of Ds were more similar to Df and Dm than to Dp. There was a limited and variable cross–reactivity with non–pyroglyphid mites. No single allergen was unique for Ds. [ABSTRACT FROM AUTHOR]

Background:Aspergillus species are common indoor airborne fungi and have been considered as causative agents of human allergic disorders. However, allergens of different Aspergillus species have not been effectively characterized. The object of this study was to identify and characterize IgE-binding components of Aspergillus oryzae. Methods. Allergens of A. oryzae were identified by immunoblot analysis using sera from asthmatic patients. The N-terminal amino acid sequences of allergens thus identified were determined by Edman degradation. The antigenic and the allergenic cross-reactivities between allergens of different fungi were analyzed by immunoblotting and immunoblot inhibition analysis, respectively, using a monoclonal antibody (MoAb) 55A against the 33-kD major allergen of Penicillium citrinum and a mixture of IgE-containing asthmatic serum samples. Results: Thirteen components of A. oryzae ranging in apparent molecular weight from 16 to 42 kD react with IgE antibodies. A 34-kD component that showed intense IgE-binding reactivity and was detectable in the highest frequency in our asthmatic serum samples tested was considered a major allergen of A. oryzae. The 34-kD component also reacted with MoAb 55A. Results from immunoblot inhibition studies also demonstrated the IgE cross-reactivity between the 34-kD major allergens of A. oryzae and P. citrinum. In addition, the sequence of the N-terminal 18 amino acid residues of the 34-kD major allergen of A. oryzae was found to be identical to that of the alkaline serine proteinase from the same Aspergillus species. Conclusion: The 34-kD major allergen of A. oryzae is an alkaline serine proteinase. There is IgE cross-reactivity between the major serine proteinase allergens of A. oryzae and P. citrinum. [ABSTRACT FROM AUTHOR]