A Case of Occupational Rhinitis Induced by Maize Pollen Exposure in a Farmer: Detection of IgE-Binding Components

Corn is a major staple food, along with rice and wheat, in many parts of the world. There are several reports of hypersensitivity to maize pollen. However, cases of occupational allergic rhinitis induced by inhalation of maize pollen are very rare. We herein report the case of a 67-year-old male with occupational rhinitis caused by occupational exposure to maize pollen in a cornfield. He showed positive responses to maize pollen, as well as grass pollens, in skin prick tests. A high level of serum immunoglobulin E (IgE) specific to maize pollen extracts was detected by an enzyme-linked immunosorbent assay (ELISA). Laboratory tests showed a high serum level of total IgE (724 kU/L) and a high level of IgE specific to maize pollen (8.32 kU/L) using the Immuno-CAP system. Occupational rhinitis was confirmed by a nasal provocation test with maize pollen extracts. IgE ELISA inhibition tests showed antibody cross-reactivity between maize pollen and grass pollen extracts. IgE immunoblotting using maize pollen extracts demonstrated a 27 kDa IgE-binding component. These findings suggest that maize pollen can induce IgE-mediated occupational rhinitis in exposed workers.     

Anaphylactic reaction to young garlic

BACKGROUND: Garlic is well known to cause contact dermatitis and asthma. However, it is a very rare cause of food allergy. We present the case of a 23-year-old woman with previous history of allergy to pollen and dried fruit, and food-dependent, exercise-induced anaphylaxis for which no specific food could be identified as responsible, who experienced an anaphylactic reaction after eating young garlic. METHODS: Skin prick tests and specific IgE immunoassay with several pollens and foods were performed, as well as the prick-prick test with young garlic and SDS-PAGE followed by immunoblotting IgE to young garlic and other Liliaceae species, mustard, sesame, parsley, celery, hazelnut, almond, and pollen of birch and mugwort. RESULTS: Skin prick tests and specific IgE were mainly positive for grass, plane tree, and mugwort pollen; peanut; hazelnut; walnut; almond; and mustard. Prick-prick tests with young garlic and garlic were positive. Total IgE was 113 U/ml. SDS-PAGE immunoblotting showed IgE-binding bands at 12 kDa to young garlic, garlic, onion, and leek extracts. Similar bands could also be detected with mugwort pollen and hazelnut extract. CONCLUSIONS: We describe IgE-mediated reaction to young garlic in a patient sensitized to pollen and dried fruit.     

Occupational asthma caused by champignon flies

BACKGROUND: Occupational bronchial asthma in mushroom (champignon) workers is unusual, although reports on it appeared in 1938 and 1951; we have not found any others since those dates. Here we report the case of a 52-year-old man who works as a champignon cultivator. He suffered rhinoconjunctivitis and asthma attacks whenever he entered the champignon culture caves. We studied flies as a possible antigen source. We collected these insects from the growing sites in order to identify them, and then prepare an extract; the samples turned out to be of two families of insects of the order Diptera, 98% from the Phoridae family (Brachycera suborder) and 2% from the Sciaridae (Nematocera suborder). METHODS: Skin prick tests, conjunctival provocation tests, serum specific IgE, specific IgE-binding fractions in immunoblotting, and monitoring of PEFR (at work and off work) were performed. RESULTS: IgE-mediated hypersensitivity to these flies was demonstrated by skin prick test, conjunctival provocation test, serum specific IgE, and IgE-binding fractions in immunoblotting. Monitoring of PEFR both at work and off work showed a clear relationship between symptoms, or fall in PEFR, and the workplace. CONCLUSIONS: We report the case of a patient suffering from asthma and rhinoconjunctivitis caused by hypersensitivity to fly proteins.     

Allergy to goat and sheep cheese with good tolerance to cow cheese

BACKGROUND: We report on a patient who experienced allergic reactions after eating goat cheese and after touching goat and sheep cheese, but not after consuming cow's milk dairy products. OBJECTIVE: To assess the allergenicity and IgE-binding capacity of the caseins from the three different species. METHODS: Skin prick tests were carried out using whole milk and caseins from three different species (goat, sheep and cow), and whey fractions of cow's milk. Total serum IgE and specific IgE to cow's milk proteins were measured by CAP system and specific IgE against caseins and whole milk were determined by ELISA technique. To evaluate allergenic cross-reactivity, inhibition of the IgE ELISA activity to goat's milk and goat casein was tested for the three caseins. SDS-PAGE and immunoblotting was used to determine IgE binding bands in caseins. RESULTS: Skin tests were positive to sheep and goat's milk, sheep and goat casein, as well as to sheep and goat cheese. Total serum IgE was 66 kU/L and IgE determinations by CAP were negative. IgE ELISA against the caseins from goat and sheep was strongly positive, whereas it was negative to cow casein. ELISA inhibition assays revealed a high degree of cross-reactivity between goat casein and sheep casein. Immunoblotting showed three IgE-binding bands in goat casein at 31, 27 and 22 kDa, which may correspond to alpha-, beta- and gamma-caseins. A band at about 31 kDa was observed in sheep casein and another band at 34 kDa was recognized in cow casein. CONCLUSION: This patient developed allergy to goat and sheep cheese with good tolerance to cow's milk. We identified goat casein as the main allergen causing sensitization in this patient as demonstrated by in vivo and in vitro tests. A high degree of cross-reactivity between goat and sheep casein was observed.     

Genetically engineered hybrid proteins from Parietaria judaica pollen for allergen-specific immunotherapy

BACKGROUND: Despite the use of conventional allergen-specific immunotherapy in clinical practice, more defined, efficient, and safer allergy vaccines are required. OBJECTIVE: The aim of the study was to obtain hypoallergenic molecules by deleting B-cell epitopes, which could potentially be applied to Parietaria judaica pollen allergy treatment. METHODS: Three hybrid molecules (Q1, Q2, and Q3) derived from fragments of the 2 major P judaica pollen allergens, Par j 1 and Par j 2, were engineered by means of PCR. Hybrid structures were compared with their natural components by means of circular dichroism, and their biologic activities were compared by using T-cell proliferation assays. Their IgE-binding activity was determined with Western blotting, skin prick tests, and enzyme allergosorbent and ELISA inhibition tests. RESULTS: The hybrid proteins, especially Q2 and Q3, revealed significantly reduced IgE reactivity compared with the natural allergens, as well as with the whole P judaica extract. Furthermore, in vivo skin prick tests showed that the hybrid proteins had a significantly lower potency to induce cutaneous reactions than the whole P judaica extract. Two (Q1 and Q2) of the 3 hybrid proteins induced a comparable T-cell proliferation response as that produced by the whole extract and natural allergens. CONCLUSION: Considering its reduced anaphylactogenic potential, together with its conserved T-cell reactivity, the engineered Q2 protein could be used in safe and shortened schedules of allergen-specific immunotherapy against P judaica pollen allergy. CLINICAL IMPLICATIONS: Recombinant hybrid Q2 is able to induce T-cell proliferation, thus evidencing a potential therapeutic effect. Its reduced IgE-binding capacity envisages an excellent safety profile.     

Occupational rhinoconjunctivitis and bronchial asthma due to Acalypha wilkesiana allergy.

BACKGROUND: Acalypha wilkesiana, or copperleaf, is a plant of the Euphorbiaceae family. Although it is widely known as an outdoor ornamental plant, no cases of A. wilkesiana allergy have been reported to date. OBJECTIVE: To describe a patient with occupational respiratory allergy to A. wilkesiana. METHODS: Extracts from A. wilkesiana leaves and flowers were used for skin prick testing, specific conjunctival and bronchial challenge tests, and in vitro studies. These studies range from A. wilkesiana specific IgE determination to sodium dodecyl sulfate-polyacrylamide gel electrophoresis immunodetection of A. wilkesiana protein bands in patient serum samples and immunoblot inhibition by preincubation with Salsola kali and Chenopodium album pollen extracts. RESULTS: Our patient had positive skin prick test reactions to A. wilkesiana leaf and flower extracts; negative reactions were found in a control group of 20 atopic patients. On immunodetection of A. wilkesiana extracts in patient serum samples, as many as 9 different IgE-binding proteins, with apparent molecular weights of 16 to 86 kDa, were revealed. Preincubation with S. kali and C. album pollen extracts completely inhibited IgE binding to the A. wilkesiana extract. Specific bronchial challenge resulted in a spirometric 30% decline in forced expiratory volume in 1 second with respect to baseline 1 minute after 1:100 (vol/vol) A. wilkesiana extract solution inhalation; 2 atopic controls had negative bronchial challenge test results. CONCLUSION: Acalypha wilkesiana is a new etiologic agent for IgE-mediated occupational respiratory allergy.     

A 17-kDa allergen detected in pine nuts

BACKGROUND: Few cases of allergy to pine nuts have been described. We report a case of anaphylactic reaction to pine nuts. The patient needed to be treated in the emergency room due to a systemic reaction immediately after eating pine nuts. METHODS: The patient was studied by prick tests and prick by prick tests. Specific IgE was measured by CAP and by SDS-PAGE/immunoblotting by a diffusion method. RESULTS: The patient showed positive prick by prick tests to pine nuts (12 mm of maximum wheal diameter). Specific IgE was positive (0.79 kU/l). The patient's serum recognized several proteins by immunoblot. However, a 17-kDa allergen band was detected with high intensity. This protein was found to be sensitive to reducing agents, losing its IgE-binding properties after reduction. CONCLUSIONS: The patient presented an IgE-mediated reaction and detected a 17-kDa protein from pine nuts not previously described.     

A baker''s occupational allergy to flour moth (Ephestia kuehniella)

BACKGROUND: Allergy to insects is common. However, few reports cover occupational sensitization to flour moth (Ephestia [syn. Anagasta] kuehniella). We describe a baker who suffered from IgE-mediated occupational respiratory allergy to flour moth. METHODS: The skin prick test (SPT) and serum IgE tests were used to evaluate the patient's sensitivity to flour moth. Allergen cross-reactivity with mites was evaluated in IgE-inhibition studies. Clinical sensitivity was evaluated by nasal challenge test. Pulmonary function tests were repeatedly monitored. RESULTS: SPT with flour moth gave a 6-mm wheal, and an elevated level of flour moth-specific IgE was measured in the patient's serum (1.9 PRU/ml, RAST class 2). Immunoblotting with the patient's serum revealed at least seven heavy IgE-binding bands with molecular masses of 22, 35, 43, 53, 65, 77, and >86 kDa in the extract of flour moth. Allergen cross-reactivity with mites was demonstrated in inhibition studies. Immediate-type allergy to flour moth was confirmed by nasal challenge. Increased daily variability of PEF values was observed during workplace exposure. CONCLUSION: A baker's occupational respiratory allergy to flour moth was confirmed.     

Diagnosis of Parietaria judaica pollen allergy using natural and recombinant Par j 1 and Par j 2 allergens

BACKGROUND: Parietaria judaica pollen is one of the main causes of allergic diseases in the Mediterranean area and contains two major allergens, called Par j 1 and Par j 2. OBJECTIVE: To evaluate the diagnostic potential of natural and recombinant forms of Par j 1 and Par j 2 in comparison with standardized P. judaica pollen extract. METHODS: Thirty patients allergic to P. judaica pollen and 15 control patients were investigated. Skin prick tests and determination of specific IgE levels were performed with commercial P. judaica extract, natural Par j 1 and Par j 2, and recombinant forms of both allergens expressed in P. pastoris. RESULTS: The whole group of patients with allergy to P. judaica had a positive skin test reaction to purified nPar j 1-Par j 2 and rPar j 2 at 5 microg/mL, and no false-positive reactions were detected. Natural and recombinant Par j 1 and Par j 2 showed no significantly different responses in skin tests compared with P. judaica extract. A high correlation was found between the serum-specific IgE levels to P. judaica extract vs. natural (R=0.996; P<0.001) and recombinant allergens (R=0.887 and 0.982 for rPar j 1 and rPar j 2, respectively; P<0.001). rPar j 2 displayed a 100% sensitivity and specificity among P. judaica-allergic patients. CONCLUSIONS: In vivo and in vitro diagnosis of P. judaica pollen allergy could be simplified using rPar j 2. This protein showed comparable IgE response and skin prick reactivity with those produced by P. judaica pollen extract.     

Vine pollen allergy in areas with a high density of vineyards.

BACKGROUND: In Castilla-La Mancha, Spain, the area with the highest density of vineyards in the world, 2 cases of Vitis vinifera pollen allergy have been previously reported. OBJECTIVE: To determine the clinical relevance and biochemical characteristics of vine pollen in the Spanish province of Ciudad Real. METHODS: We designed a prospective study of patients treated in the allergy units from Puertollano and Ciudad Real for respiratory symptoms of 4 months' duration in the year 2000. Skin prick tests with a standard aeroallergen battery and V vinifera pollen extract were performed on all patients. We also performed conjunctival and bronchial provocation tests and serum specific IgE and sodium dodecyl sulfate-polyacrylamide gel electrophoresis immunoblotting on the patients who tested positive for V vinifera pollen. RESULTS: We included 200 patients, 98 sensitized to any pollen and 9 to V vinifera pollen. We found 8 of 9 positive conjunctival provocation test results and a positive bronchial provocation result to vine pollen in a vine grower. Serum specific IgE against V vinifera pollen was detected in 9 of 9 patients. Immunoblotting with V vinifera pollen extract showed IgE-binding bands at 45 and 67 kDa. CONCLUSIONS: Vine pollen could be the cause of pollinosis in exposed patients living in areas with a high density of vineyards.     

Identification of Parietaria judaica pollen allergens

Parietaria judaica pollen allergens, fractionated by SDS-polyacrylamide gel electrophoresis and transferred to nitrocellulose membranes, were identified using 52 sera collected in Australia and Sicily from P. judaica pollen-allergic patients. IgE-binding pollen components transferred to nitrocellulose were detected by reaction with 125I-anti-human IgE and autoradiography. Nine pollen components, ranging in molecular weight (MW) from approximately 10,000 to 80,000 daltons, bound IgE antibodies but the two fastest migrating components sometimes each separated into two very closely migrating bands. The faster of the two components exhibiting doublet formation (MW approximately 10,000 daltons) showed by far the highest frequency of IgE binding, being recognised by 50 of the 52 sera examined. Although patients' IgE reaction patterns to P. judaica allergens were heterogeneous, the degree of heterogeneity was much less than that observed with house dust mite and other pollen extracts studied by electrophoretic transfer analysis. Results with gradient gel-nitrocellulose transfer experiments which showed no IgE-binding components with MWs less than 70,000 daltons, and comparisons of our electroblotting results with crossed radioimmunoelectrophoresis results of others, suggested that the doublet proteins with MWs of approximately 10,000 probably bind to higher MW proteins in P. judaica pollen extracts.     

Involvement of Can f 5 in a Case of Human Seminal Plasma Allergy

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.     

Pollinosis to Ricinus communis (castor bean): an aerobiological, clinical and immunochemical study

BACKGROUND: Ricinus communis (castor bean) is a species included into the Euphorbiaceae family, common to all the warm regions of the world. Although the allergenicity of its seed is well known, references are scarce regarding the role played by its pollen as a pneumo-allergen. OBJECTIVES: To carry out an aerobiological study of this pollen in the Málaga area (southern Spain); describe the physicochemical characteristics of its most relevant allergens; and to demonstrate the existence of patients with respiratory allergy due to this pollen. METHODS: A Burkard spore trap was used for the aerobiological study from 1992 to 1996. Skin prick tests with castor bean pollen extract were performed to 1946 patients with rhinitis and/or asthma. Specific IgE levels were measured in castor bean-positive SPT patient sera. Immunochemical characterization of the most relevant allergens was performed using electrophoretic techniques. In vitro cross-reactivity studies using positive patient sera were carried out. Nasal challenge tests were done in 32 subjects randomly selected from the sensitized patient group. RESULTS: Castor bean is a perennial pollen with total annual pollen levels never exceeding 1%. One hundred and eighteen (7.7%) patients showed positive prick test (74 rhinitis, 36 rhinitis and asthma, eight asthma). Nine were monosensitized. Specific IgE levels were > or =0.35 PRU/mL in 39 (33%) of patient sera. Nasal challenge test: 10 subjects presented non-specific nasal hyperactivity, 15 were positive and seven negative. The molecular masses and isoelectric points of the main IgE-binding proteins, ranged from approximately 67-15.5/14.5 kDa and approximately 4.5-5.5, respectively. Profilin of the extract was purified by poli-L-proline-Sepharose chromatography and it appeared as one of the most frequent allergens. CONCLUSION: Castor bean pollen is an allergen which causes respiratory (mainly nasal) symptoms.     

Beer‐induced anaphylaxis: identification of allergens

BACKGROUND: We report on a 21-year-old atopic woman who developed urticaria, angioedema of the face, and wheezy dyspnea shortly after drinking beer and after eating a corn-made snack. METHODS: Skin prick tests and specific IgE determinations to beer ingredients and cereal extracts were performed. Immunoblotting inhibition assays were carried out to investigate possible common allergens shared by barley and malt with corn. RESULTS: Skin prick tests and specific IgE measurements with beer, barley, malt, wheat, corn, rye, rice, and oat flour were positive. Ten pollen-allergic patients showed negative skin tests to beer. Double-blind, placebo-controlled, oral challenge tests with sodium metabisulfite and wheat flour were negative. Immunoblotting demonstrated several IgE-binding bands at 31-56 kDa in malt and barley extracts, and a major band at 38 kDa in the beer extract. Immunoblot inhibition assays showed that malt extract was able to inhibit most of the IgE-binding bands in wheat and corn extracts, whereas corn did not produce significant inhibition to barley and malt extracts. CONCLUSIONS: This patient developed type I hypersensitivity to barley/malt and corn. Although she also showed IgE reactivity to wheat and other cereals, no symptoms were elicited upon ingestion of these cereals, probably indicating latent sensitization to them.     

Biological characterization of glutaraldehyde-modified Parietaria judaica pollen extracts

BACKGROUND: Allergoids are widely used in specific immunotherapy (SIT) for the treatment of IgE-mediated allergic diseases, but all techniques for standardization of conventional allergic extracts may not be appropriate for standardization of a glutaraldehyde (GA)-modified extract because of the unique characteristics of these extracts. OBJECTIVE: To assess an accurate methodology for standardization of chemically modified extracts. METHODS: GA-modified extracts from Parietaria judaica pollen were purified by diafiltration. Biochemical properties were investigated by determination of amino groups, chromatography, and SDS-PAGE. The IgE-binding activity was determined by skin prick test, enzyme allergosorbent test inhibition, basophil activation, and histamine release tests. Peripheral blood mononuclear cells (PBMCs) from P. judaica pollen-allergic subjects were stimulated with either native or allergoid extracts, and proliferation was measured. RESULTS: Biochemical data indicated a high degree of allergen polymerization resulting in extract components higher than 100 kDa. IgE-binding activity, both in vivo and in vitro, was reduced by more than 99.8%. Both allergen and allergoid induced PBMC proliferation and synthesis of blocking IgG antibodies at similar rates. Moreover, no evidence of introduction of new determinants by chemical modification was found. CONCLUSIONS: The preparation of GA-modified extracts by diafiltration is faster and more reliable than previous chromatographic methods. These modified extracts have drastically reduced their allergenicity while maintaining their immunogenicity, and therefore they can be used in safer and shortened schedules of SIT.     

Possible relationship between systemic side effects and sensitization to rPar j 2 in allergic patients submitted to an ultra-rush (20 min) sublingual immunotherapy and selected by component resolved diagnosis

BACKGROUND: The pollen of Parietaria spp., a weed of the Urticaceae family, is a major cause of respiratory allergy in the Mediterranean area, where the most common species are Parietaria judaica and Parietaria officinalis. In this study, we evaluated the specific serum IgE-binding profiles to individual P. judaica pollen recombinant major allergen, and Phleum pratense cytoskeletal profilin and a 2-EF-hand calcium-binding allergen homologous to cross-reactive Parietaria pollen allergens, in patients allergic to pollen with positive skin test towards Parietaria spp. extract. METHODS: The present observation included 220 patients from the province of Cuneo, north-west Italy, all suffering from rhino-conjunctivitis and/or asthma selected on the basis of skin test positive to P. judaica extract. The sera were evaluated for specific IgE reactivity to P. judaica pollen major recombinant(r) allergen Par j 2, Phleum pratense pollen allergens rPhl p 7 (2-EF-hand calcium binding protein) and rPhl p 12 (profilin), both identified as cross-reactive Parietaria spp. allergens, using Pharmacia CAP System. Out of 220 patients, 37 patients with IgE reactivity to rPar j 2 and 105 patients sensitized to at least one timothy pollen major allergen (i. e. rPhl p 1, rPhl p 2, natural Phl p 4 and rPhl p 6) were submitted to an ultra-rush protocol of sublingual immunotherapy (SLIT). The occurrence of adverse reactions were evaluated in both groups. RESULTS: All 220 patients with pollinosis and positive in vivo skin prick tests had in vitro positive CAP results to P. judaica natural extract. On the contrary, in these patients the prevalence of Par j 2-specific IgE was only 33.2% (73/220). In fact, 116/220 (52.7%) patients with serum specific IgE to crude Parietaria pollen extract had specific IgE to Phl p 12, 18/220 (8.1%) subjects with specific IgE to rPhl p 12 also exhibited specific IgE to Phl p 7 and 26/220 (11.8%) subjects had specific IgE against rPhl p 7. Particularly, geometric mean (25th-75th percentile) of specific IgE to rPar j 2 were as follows: 2.87 kUA/l (1.005-7.465). Out of 73 patients with specific IgE to rPar j 2, 7 subjects (9.6%) had also specific IgE to rPhl p 7, 12 (16.4%) had specific IgE to rPhl p 12 and 4 (4.1%) patients had specific IgE to both recombinant allergens. Of 37 patients under an ultra-rush protocol of SLIT, 3 subjects (8.1%) experienced generalized urticaria, and 1 of them also had diarrhea 3 h after the last dose of Parietaria judaica extract oral-vaccine administration. On the contrary, no systemic reactions were observed in 105 patients after Phleum pratense extract oral intake after a similar ultra-rush SLIT protocol (p = 0.0046). CONCLUSIONS: In the light of present findings, allergen extract-based diagnosis, in vivo and in vitro, cannot discriminate allergic patients that are genuinely sensitized to Parietaria spp. major allergens or to other major allergens to which current immunotherapeutic allergy extracts are standardized. Therefore, in vitro component resolved diagnosis is the unique tool to define the disease eliciting molecule(s). Finally, during sublingual immunotherapy, not only the dose of allergen, but also the biochemical characteristic of the major allergen administered may be an important factor in determining possible systemic reactions.     

BSA-ELISA初步检测短穗鱼尾葵花粉特异性IgE

目的对短穗鱼尾葵花粉粗浸液的主要变应原进行分析、鉴定。方法通过SDS-PAGE分析短穗鱼尾葵花粉蛋白质组份,采用Western blotting鉴定主要变应原,以短穗鱼尾葵花粉粗浸液包板,摸索出其包被浓度、血清稀释度和酶结合物浓度,采用BSA-ELISA法对短穗鱼尾葵花粉过敏患者血清进行初步检测,并与皮肤挑刺试验比较。结果短穗鱼尾葵花粉粗浸液SDS-PAGE显示有30余条蛋白条带,其中主要蛋白条带有10条,Western blotting显示5例短穗鱼尾葵花粉过敏患者的混合血清能与其中3条蛋白条带起反应,分子量分别是26000、14000和12000Mr。BSA-ELISA检测短穗鱼尾葵花粉特异性IgE,最适粗浸液稀释度为1：100,血清稀释倍数为1：5,生物素化抗体为1：1000,辣根过氧化物酶标记的链霉亲和素（strepavidin-HRP）为1：1000。在此条件下BSA-ELISA与浸液皮试比较,检出结果与皮试阳性患者血清符合率为90%,与皮试阴性患者符合率为80%,与健康人对照检测符合率为100%。结论本实验对短穗鱼尾葵花粉主要变应原进行了分离和鉴定,BSA-ELISA法测定结果与皮肤挑刺试验初步比较符合率较好。     

An odorant-binding protein as a new allergen from Siberian hamster (Phodopus sungorus)

A case of anaphylaxis following a bite from a Siberian hamster (SH; Phodopus sungorus) is described. Skin prick tests with hair, urine and salivary gland extracts from SH were positive, while the tests were negative for hair extracts from other rodents. IgE immunoblotting with the patient serum revealed 3 IgE-binding bands of about 18, 21 and 23 kDa. When the patient's serum was preincubated with rabbit, mouse and gerbil hair extracts, no inhibition of the 3 SH IgE-binding bands was demonstrated. Proteins extracted from the 3 bands were analyzed by N-terminal sequencing and matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry, and peptides were sequenced. IgE-binding bands were identified as being an odorant-binding protein belonging to the lipocalin family. Analysis of the 3 IgE-binding bands found in the hair, urine and salivary glands of SH showed a new allergenic protein lacking cross-reactivity with allergens from other rodents. The 3 bands likely correspond to isoforms of a single allergen.     

Identification of orchard grass (Dactylis glomerata) pollen allergens following electrophoretic transfer to nitrocellulose

Orchard grass (cocksfoot) pollen extracts, fractionated by polyacrylamide gradient electrophoresis or SDS gel electrophoresis were electroblotted onto nitrocellulose membranes and probed with sera from orchard grass pollen-allergic patients and 125I-anti-human IgE. The IgE-binding components of the pollen were detected by autoradiography. Elution studies showed that allergens could be extracted immediately and continuously over a 3-hour period. Two fractions of MWs 28,000 and 30,000 could be detected only after 20 min extraction. SDS-PAGE separations gave the better resolution revealing 19 electrophoretically-separate components, 13 of which bound human IgE. All of the IgE-binding components had MWs in the range 14,000 - 70,000. Three of the bands bound IgE from more than 85% of the serum samples. Following gradient gel electrophoresis, IgE binding was exhibited by 10 bands in the range MW 5,000 to greater than 669,000. The technique used allows one to quantitatively examine patients' sera for allergen-specific IgE antibodies and to identify the clinically important allergens. Results revealed numerous allergenic components over a wide MW range while patterns of IgE binding with different patients' sera demonstrated a great diversity of IgE antibody responses. This study demonstrates the suitability of the electroblotting technique combined with autoradiography for the investigation of allergenic components of grass pollen extracts and hence has application to extract standardization and immunotherapy. Such studies can be carried out rapidly, economically and with a high degree of sensitivity.     

Occupational rhinitis and asthma due to crickets.

BACKGROUND: Insects may cause airborne hypersensitivity reactions. However, few reports exist on specific allergy to crickets. OBJECTIVE: To report a case of occupational rhinitis and bronchial asthma in a cricket farm worker. METHODS: A 28-year-old woman developed rhinitis and bronchial asthma related to her job in a farm where she was exposed to crickets: Gryllus campestris, Gryllus bimaculatus, and Acheta domestica. Extracts were prepared from whole and crushed bodies and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Skin prick tests, specific IgE assays (enzyme allergosorbent test [EAST], immunoblotting, EAST inhibition assays), serial peak expiratory flow monitoring at work, and specific (A domestica) and nonspecific bronchial challenge tests were performed. RESULTS: Skin prick test results were positive for G campestris, G bimaculatus, and A domestica. Levels of specific IgE were 2.9, 2.4, and 5.4 kU/L, respectively. The total IgE level was 131 kU/L. Serial peak expiratory flow monitoring at work was consistent with occupational asthma. The result of a bronchial challenge test with A domestica was positive with a dual response and elicited an increase in nonspecific bronchial hyperresponsiveness. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis immunoblotting revealed a similar pattern of IgE-binding bands with the 3 cricket extracts (bands of 78 and 64 kDa appeared in nonreducing conditions, whereas bands of 107 to 80, 58, and 52 kDa appeared in reducing conditions). None of these bands was detected by control sera. EAST inhibition studies showed a high degree of cross-reactivity among the 3 species. CONCLUSION: Crickets are responsible for occupational rhinitis and asthma by an IgE mechanism. Cross-reactivity among the crickets tested in our study was found.