Poor association between allergen-specific serum immunoglobulin E levels, skin sensitivity and basophil degranulation: a study with recombinant birch pollen allergen Bet v 1 and an immunoglobulin E detection system measuring immunoglobulin E capable of binding to FcɛRI

BACKGROUND: Results from several studies indicate that the magnitude of immediate symptoms of type I allergy caused by allergen-induced cross-linking of high-affinity Fc epsilon receptors on effector cells (mast cells and basophils) is not always associated with allergen-specific IgE levels. OBJECTIVE: To investigate the association of results from intradermal skin testing, basophil histamine release and allergen-specific IgE, IgG1-4, IgA and IgM antibody levels in a clinical study performed in birch pollen-allergic patients (n = 18). METHODS: rBet v 1-specific IgEs were measured by quantitative CAP measurements and by using purified Fc epsilon RI-derived alpha-chain to quantify IgE capable of binding to effector cells. Bet v 1-specific IgG subclasses, IgA and IgM levels were measured by ELISA, and basophil histamine release was determined in whole blood samples. Intradermal skin testing was performed with the end-point titration method. RESULTS: Our study demonstrates on the molecular level that the concentrations of allergen-specific IgE antibodies capable of binding to Fc epsilon RI and biological sensitivities are not necessarily associated. A moderate association was found between cutaneous and basophil sensitivity. CONCLUSION: Our results highlight the quantitative discrepancies and limitations of the present diagnostic tools in allergy, even when using a single allergenic molecule. The quantity of allergen-specific serum IgE is only one component of far more complex cellular systems (i.e. basophil-based tests, skin tests) used as indirect diagnostic tests for IgE-mediated allergic sensitivity.     

油菜花粉的化学成分研究

目的:研究油菜花粉的化学成分.方法:采用硅胶柱色谱、Sephadex LH-20凝胶柱色谱、反相柱色谱等方法进行分离纯化,根据波谱数据进行结构鉴定.结果:从油菜花粉的醋酸乙酯和正丁醇部位分离得到9个单体化合物,分别为山柰酚-3-O-β-D-葡萄糖-(1→2)-β-D-葡萄糖苷(1),山柰酚-3,4'-双-O-β-D-葡萄糖苷(2),槲皮素-3-O-β-D-葡萄糖-(1→2)-β-D-葡萄糖苷(3),烟酸(4),烟酰胺(5),香豆酸-4-O-β-D-葡萄糖苷(6),山柰酚(7),β-谷甾醇(8),5-羟甲基糠醛(9).结论:化合物1～6均为首次从油菜花粉中分离得到.     

Antioxidant and antiinflammatory activity of pine pollen extract in vitro

To determine the medicinal properties of pine pollen, the antioxidant and antiinflammatory activities of the ethanol extract of pine pollen extract (PPE) were investigated. PPE displayed a strong free radical scavenger activity on 1,1‐diphenyl‐2‐picrylhydrazyl radical and hydrogen peroxide. It was observed also that the antioxidant activity, measured by the ferric thiocyanate method, increased with the addition of PPE to the linoleic acid emulsion system. PPE was also found to inhibit significantly the amount of malondialdehyde and protein carbonyls formed from liver homogenate. Like the antioxidant activity, the reducing power of PPE was excellent. Thereafter, the study investigated the effects of PPE in modulating the production of pro‐inflammatory mediators in lipopolysaccharide (LPS)‐activated RAW 264.7 macrophages, and the effect of PPE on interleukin (IL)‐1β‐induced matrix metalloproteinases (MMPs) production and mitogen‐activated protein kinases (MAPKs) activation in the human synovial sarcoma cell line, SW982. PPE was found to inhibit the production of nitric oxide, tumor necrosis factor‐α, IL‐1 and IL‐6 in LPS‐activated macrophages. Treatment with PPE at 10 µg/mL significantly (p < 0.05) inhibited IL‐1β‐induced MMPs (MMP‐1 and ‐3) production in SW982 cells. IL‐1β‐induced JNK activation was inhibited by PPE (10 µg/mL), whereas p38 and ERK1/2 were not affected. These findings suggest that pine pollen is a potential antioxidant and beneficial for inflammatory conditions through down‐regulation of JNK and MMPs. Copyright © 2008 John Wiley & Sons, Ltd.     

Sensitization to Zygophyllum fabago pollen. A clinical and immunologic study

Zygophyllum fahago is a herbaceous plant found widely in the Mediterranean area. There are no previous reports of its allergenicity. An aerobiologic and clinical survey was conducted in Murcia, southern Spain, to determine the quantity of airborne pollen and establish the possible role of this pollen as a cause of allergic symptoms. With a Hirst volumetric trap, we determined the atmospheric concentrations of this pollen in 1993, 1994,1995, and 1996. Of 1180 patients tested, 181 (15,34%) had a positive skin test. To determine its allergenicity, we divided 47 patients into three groups: in group 1, all the patients had symptoms of rhinoconjunctivitis plus asthma; in groups 2 and 3, rhinoconjunctivitis. In group 1, we performed a bronchial provocation test (BPT): in groups 2 and 3, we performed nasal provocation (NPT) and conjunctival provocation (CPT) tests, respectively, SDS-PAGE was used to characterize the antigenic fractions and RAST inhibition to determine cross-reactivity with other pollens. The pollen dispersion period is from May to September (445 grains/m³), BPT was positive in 13 of 15 patients, NPT in 14 of 16 patients, and CPT in 13 of 16 patients. RAST inhibition revealed cross-reactivity with Mercurialis, Ricinus, Olea. and Betula. SDS-PAGE identified 25 IgE antibody-binding components, five of which (60, 65, 41, 38, and 15.5/14,7 kDa) were recognized by 40% of the sera. By SDS-PAGE immunoblotting with sunflower antiprofilin rabbit serum and affinity chromatography we established that the Z. fahago extract has profilin. This study shows that this pollen becomes airborne and elicits an IgE response which triggers respiratory symptoms in allergic subjects.     

南昌市中心气传花粉调查

目的：探明南昌市中心气传致敏花粉的种类、数量及季节消长规律，提高过敏性疾病的防治水平。方法：2000年4月--2001年4月期间采用Durham重量法进行为期一年的气传花粉调查，分析其飘散规律。结果：全年都有气传花粉的飘散，存在两次高峰，其一为三、四月，占17．24％及9．15％，以松科、柏科、杉科、桑科及柳属为主；其二为九、十月份，占18．13％及38．52％，以豚属、蒿属、禾本科、藜苋科及Lu草属为主。结论：为本地区过敏性疾病的特异性诊断和治疗及流行病学研究提供了科学依据。     

Distinguishment of A 42 Capsomere Structure of Icosohedral Virion from A 32 One by Electron Microsco

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Effect of various stabilizing agents on Imperata cylindrica grass pollen allergen extract

BACKGROUND: Allergen extracts are unstable, heat labile or susceptible to proteases. Stability of allergen extracts is important for proper diagnosis and therapy of allergic disorders. OBJECTIVE: The present study was undertaken to determine the preservation and stabilization conditions of Imperata cylindrica (Ic) grass pollen extract. METHODS: The Ic extract was kept with 0.1 mepsilon-aminocaproic acid (EACA), 0.75 m sucrose, 5% glycerol, 0.03% human serum albumin (HSA) or 0.4% phenol for different time periods. The extracts were stored for 3, 6 and 12 months each at 4 degrees C, 4 degrees C with daily exposure to room temperature (RT) for 1 h, and RT. The quality of extracts was analysed by SDS-PAGE, Western blot, ELISA, ELISA inhibition and skin test. RESULTS: Extracts kept with EACA and sucrose retained most of the protein bands followed by glycerol as determined by SDS-PAGE and Western blot during all storage periods and conditions in comparison with standard extracts. The extracts kept with HSA, phenol and without preservative (WP) showed protein degradation below 33 kDa after 3 months storage at all conditions. However, a 67-kDa allergen was stable in these extracts. EACA extract required 75 to 120 ng of protein for 50% inhibition in IgE binding under different conditions, whereas standard extract required 70 ng for the same. ELISA also demonstrated high allergenic reactivity of EACA extract. ID test on allergy patients with EACA extract demonstrated same allergenic potency as that of standard extract. CONCLUSION: EACA is the best preservative/stabilizing agent of Ic pollen extract, followed by sucrose and glycerol. Ic extract kept with phenol, HSA and without preservative showed degradation within 3 months. EACA preserved extract is equally potent as that of standard extract up to 1 year's storage.     

Comparison of allergenicity and immunogenicity of an intact allergen vaccine and commercially available allergoid products for birch pollen immunotherapy

BACKGROUND: Specific immunotherapy with intact allergen vaccine is a well-documented treatment for allergic diseases. Different vaccine formulations are currently commercially available, the active ingredient either being intact allergens or chemically modified allergoids. The rationale behind allergoids is to decrease allergenicity while maintaining immunogenicity. However, data from the German health authorities based on reporting of adverse events over a 10-year period did not indicate increased safety of allergoids over intact allergens. OBJECTIVE: The objective of this study was to investigate the effect of chemical modification on allergenicity and immunogenicity comparing four commercial allergoid products for birch pollen immunotherapy with an intact allergen vaccine. METHODS: Solid-phase IgE inhibition and histamine release assays were selected as model systems for allergenicity, and a combination of human T cell proliferation and IgG titres following mouse immunizations were used to address the immunogenicity of the intact allergen vaccine and the four allergoids. In all assays, the products were normalized with respect to the manufacturer's recommended maintenance dose. RESULTS: IgE inhibition experiments showed a change in epitope composition comparing intact allergen vaccine with allergoid. One allergoid product induced enhanced histamine release compared to the intact allergens, while the other three allergoids showed reduced release. Standard T cell stimulation assays using lines from allergic patients showed a reduced response for all allergoids compared with the intact allergen vaccine regardless of the cell type used for antigen presentation. All allergoids showed reduced capacity to induce allergen-specific IgG responses in mice. CONCLUSION: While some allergoids were associated with reduced allergenicity, a clear reduction in immunogenicity was observed for all allergoid products compared with the intact allergen vaccine, and the commercial allergoids tested therefore do not fulfil the allergoid concept.     

鲁南地区大气花粉及其致病性探讨

目的 探讨鲁南地区气传花粉的种类，分布，数量及其致病性。方法 采用空气曝片的方法，连续2年收集气传花粉，在光学显微镜下进行阅片鉴定，并将采集到的花粉处理后，制备成花粉变应原疫苗，进行皮肤试验。结果 2年共收集花粉10813粒，18个科属，每年3－5月和8－9月出现飘散高峰。主要致敏花粉是蒿属，Lu草，杨树及松树花粉。结论 鲁南地区的气传花粉主要包括Lu草属，松属，杨属，蒿属，藜属，柳属，榆属，禾本科，地肤，臭椿属，蓖麻属，柏科，核桃，向白葵属，栎属，桦属，银杏属，豚草等，以Lu草，松属，杨属，蒿属，藜属，禾本科花粉量较大，占70％。主要致敏花粉是蒿属，Lu草，杨树及松树花粉。