油菜花粉过敏原的分析、鉴定与纯化

目的对油菜花粉的变应原组分进行鉴定及初步的分离及纯化。方法提取油菜花粉粗提液,然后通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)分离油菜花粉的蛋白质组分并测定其相对分子质量,采用免疫印迹(Western blotting)法鉴定其变应原成分,并通过离子交换层析对油菜花粉变应原进行初步分离纯化,免疫印迹进行检测。结果油菜花粉粗提液有10余条蛋白带,其中相对分子质量为30 000、25 000、15 000和10 000的蛋白可与油菜花粉过敏性病人血清IgE结合,其中15 000和10 000为主要变应原;离子交换层析结果显示主要过敏原成分主要分布在Ⅰ、Ⅱ和Ⅲ峰中。结论对油菜花粉变应原进行了初步的分离、鉴定和纯化,为临床油菜花粉变态反应疾病的诊断和治疗奠定了基础。     

重阳木花粉过敏原的分析、鉴定与纯化

 【摘要】 目的　对重阳木花粉变应原蛋白进行分析、鉴定与纯化。方法　提取这重阳木花粉的粗提液,通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS - PAGE)分离粗提液蛋白质组分并测定其分子量,收集过敏病人血清,采用免疫印迹(Western - blotting)法鉴定其变应原成分,通过离子交换层析对重阳木花粉变应原进行初步纯化和免疫印迹鉴定。结果　重阳木花粉有18条主要蛋白带,12 000Mr和14 000Mr为重阳木花粉特异性变应原;通过离子交换层析方法纯化出重阳木花粉分子量为12 000Mr和14 000Mr的变应原主要分布在II峰中。结论　对重阳木花粉变应原进行了初步的分离、鉴定和纯化,为临床重阳木花粉过敏疾病的诊断和治疗奠定了基础。     

重阳木花粉过敏原的分离、纯化和鉴定

目的对重阳木花粉变应原蛋白进行分离、纯化和鉴定。方法采用Coca s液提取重阳木花粉的粗提液,通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)分离粗提液蛋白质组分,并测定其分子质量;收集过敏患者血清,用Western blot法鉴定其变应原成分;通过离子交换层析对重阳木花粉变应原进行初步纯化和免疫印迹鉴定。结果分离得到重阳木花粉18条蛋白带,其中分子质量为12和14 ku的是重阳木花粉的特异性变应原,通过离子交换柱层析方法纯化得到其相应的纯化蛋白。结论对重阳木花粉变应原进行了初步的分离、纯化和鉴定,为临床重阳木花粉过敏疾病的诊断和治疗奠定了基础。     

艾蒿花粉主要变应原的分离、纯化与鉴定

目的　对我国蒿属花粉中常见、重要的变应原艾蒿花粉进行分离、鉴定与纯化。方法采用不同的提取液得到艾蒿花粉粗浸液 ,经饱和 (NH4 ) 2 SO4 分级沉淀后用聚丙烯酰胺凝胶电泳 (SDS PAGE)分离蛋白质组分 ,并用凝胶成像系统测定各组分的相对分子质量 (Mr) ;采用Westernblot鉴定其主要及次要变应原 ;通过DEAE CelluloseDE 32离子交换层析 (ionexchangechromatography ,IEC)和SephadexG 75凝胶层析 (gelchromatography)对艾蒿花粉变应原进行纯化。结果　分离后得到 2 0多种蛋白质组分 ,其中Mr 为 5 8× 1 0 3、38× 1 0 3、2 5× 1 0 3、2 0× 1 0 3、1 6× 1 0 3等 5个条带蛋白含量最丰富 ;分离到的蛋白质组分中有 9种蛋白能与确诊的蒿属花粉过敏患者血清中蒿属花粉特异性IgE结合 ,其中Mr 为 6 2× 1 0 3、4 3× 1 0 3、38× 1 0 3的蛋白条带的结合率最高 ;经纯化后仅得到Mr 为 6 2× 1 0 3的主要变应原。结论　艾蒿花粉的主要变应原Mr 分别为 6 2× 1 0 3、4 3× 1 0 3和 38× 1 0 3,层析技术可以对Mr 为6 2× 1 0 3的主要变应原成分进行纯化。     

椰子花粉过敏原基因的克隆表达、纯化及免疫学鉴定

目的:克隆并表达椰子花粉中泛变应原肌动蛋白抑制蛋白(Profilin).方法:利用RT-PCR结合RACE技术克隆椰子花粉中泛变应原profilin的全长基因,并进行序列分析.然后设计带有酶切位点的特异性引物,采用RT-PCR获得整个椰子花粉profilin的开放阅读框,将其与pET28a载体连接并转化大肠杆菌BL21(DE3)进行诱导表达,通过Ni2+亲和层析柱对重组蛋白进行纯化,采用Western blot检测其IgE结合活性.结果:克隆获得了椰子花粉profilin的全长基因,由608个碱基组成,开放阅读框为396个碱基(包括终止密码子),编码131个氨基酸.经分析,这个序列编码的蛋白为小分子量酸性蛋白,等电点为4.61,分子量约为14 kD.此序列已被GeneBank收录,登陆号为EF173598.重组椰子花粉profilin在大肠杆菌中高效的表达和纯化后,经Western blot检测具有良好的免疫学活性.结论:成功地克隆和表达了椰子花粉profilin,为该花粉profilin用于椰子花粉过敏诊断和免疫治疗提供了理论依据.     

方斑东风螺过敏原的分离、鉴定与纯化

目的 对方斑东风螺的主要过敏原进行分析、鉴定与纯化.方法 通过SDS-PAGE电泳分离方斑东风螺的蛋白质组份,采用免疫印迹(Western-blotting)方法 鉴定过敏原,通过离子交换层析对方斑东风螺主要过敏原进行初步纯化.结果 方斑东风螺粗提液SDS-PAGE显示其主要蛋白条带主要有7条,Western-blotting显示过敏患者的阳性混合血清能与其中3个蛋白条带起反应,相对分子质量分别是56 000、28 000和22 000.离子交换层析可初步纯化出28 000和22 000的过敏原蛋白.结论 本实验对方斑东风螺过敏原进行了分离和鉴定,并初步纯化出方斑东风螺的主要过敏原.     

带鱼过敏原的分离、鉴定与纯化

目的分离、鉴定和纯化带鱼特异性过敏原。方法采用Coca’s提取液提取带鱼蛋白；十二烷基磺酸钠一聚丙烯酰胺凝胶电泳（SDS—PAGE）和Western—blotting分析其中的过敏原；阴离子交换层析对过敏原进行分离纯化。结果带鱼粗浸液蛋白分子量在8～130kDa之间；Western—blotting检测到分子量为12、18、25、27、29、34、38、54和60kDa的过敏原蛋白；通过离子交换层析分离得到较纯的分子量为18、38kDa的过敏原蛋白，且具有免疫活性。结论发现了带鱼中多种过敏原，并对2种过敏原分离纯化，为带鱼过敏的诊断和治疗奠定了理论基础。     

斑节对虾过敏原的分离、鉴定与纯化

目的 对斑节对虾的主要过敏原进行分析、鉴定与纯化.方法 通过SDS-PAGE电泳分离斑节对虾的蛋白质组份,采用免疫印迹(Western-blotting)方法鉴定过敏原,通过离子交换层析对斑节对虾主要过敏原进行初步纯化.结果 斑节对虾粗提液SDS-PAGE显示其主要蛋白条带主要有7条,Western-blotting显示对斑节对虾过敏患者的阳性混合血清能与7个蛋白条带起反应,相对分子质量分别为71 000、43 000、34 000、23 000、21 000、20 000和19 000,离子交换层析可初步纯化出相对分子质量为34000和21 000的过敏原蛋白.结论本实验对斑节对虾过敏原进行了分离和鉴定,并初步纯化出斑节对虾的主要过敏原.     

梭子蟹变应原的分离、纯化与鉴定

目的：对梭子蟹（Portunus pelogicus（Linnaeus））变应原进行分离,鉴定其主要及次要变应原,采用蛋白纯化技术获取梭子蟹天然的主要变应原并进行鉴定,为标准化变应原疫苗的研制提供理论依据.方法：取常规方法制备梭子蟹浸出液,经SDS-PAGE分离,测定各组分的相对分子量;同时用26例对蟹过敏的病人血清进行Western blot,鉴定其主要及次要变应原;利用快速制备液相色谱（FPLC）纯化技术（凝胶过滤层析和离子交换层析）获取主要变应原并作鉴定.结果：SDS-PAGE显示梭子蟹有19条可辨蛋白带,分子量在13 000～90 000之间,其中主带有9条,分子量是20 900、24 200、27 100、29 200、33 700、38 900、48 700、74 700、89 100;Western blot结果表明,26例蟹过敏患者血清全部呈阳性反应,浸出液中共有5条致敏条带,其中分子量在74 400、48 700的是主要变应原,阳性反应率均为100%;纯化后获取了74400、48700的主要变应原;经过免疫鉴定证实其具有免疫活性.结论：梭子蟹74 400和48 700的变应原为主要变应原,层析技术可以对分子量为74400和48700的主要变应原成分进行纯化.     

Isolation and purification of a major allergen from Parietaria officinalis pollen

A major allergen of Parietaria officinalis, a species responsible for a large number of respiratory allergies in Mediterranean areas, has been identified and characterized. This allergen (Pol) was found in the fraction which precipitates between 70 and 100% ammonium sulphate saturation. Pol showed a molecular weight of 15,000 daltons as determined by SDS-PAGE and HPLC. The pI of Pol was in the pH region 4-6, IEF showing four major bands. Two major bands were shown by CIE, CRIE and immunoblotting; major contaminants or aggregates were also revealed by the latter technique and by HPLC. Pol showed an allergic specific activity 2 times higher than the crude extract; moreover it was shown to be a major allergen since it inhibited 29 out of 30 sera from allergic patients sensitive to P. officinalis.     

Analysis of sequential immunoglobulin E-binding epitope of Japanese cedar pollen allergen (Cry j 2) in humans, monkeys and mice

BACKGROUND: Japanese cedar (Cryptomeria japonica; CJ) pollinosis has been reported to occur naturally in Japanese monkeys (Macaca fuscata) as well as in humans. Most human patients and monkeys with pollinosis have specific IgE for Cry j 2, a major allergen of CJ pollen. OBJECTIVE: The main purpose of this study was to identify IgE B cell epitopes of Cry j 2 using a synthetic peptide in humans, monkeys and mice. METHODS: We synthesized 38 overlapping peptides that span the entire length of Cry j 2. We examined the B cell epitopes of Cry j 2 that are recognized by IgE in the sera of human patients and monkeys with pollinosis and immunized mice using synthetic peptides of Cry j 2. We also examined the reaction of Cry j 2-specific mouse monoclonal IgG antibodies to the peptides. Furthermore, we conducted a histamine release assay with leucocytes from a pollinosis patient using human serum albumin (HSA) conjugated with the peptides as a B cell epitope. RESULTS: We found that 16 of the 20 pollinosis patients who had specific IgE to Cry j 2 also exhibited IgE reaction with some Cry j 2 peptides. Of these 16 patients, 10 exhibited IgE reaction with Cry j 2 peptide no. 13 (121GQCKWVNGREICNDRDRPTA140). Five of the seven monkeys with CJ pollinosis exhibited a reaction with peptide no. 13. Furthermore, IgE in mice immunized with Cry j 2 and two mouse monoclonal IgG antibodies reacted with peptide no. 13. Peptide no. 13-conjugated HSA showed the release of histamine from basophils. Furthermore, to determine the minimum epitope in peptide no. 13, we conducted an enzyme-linked immunosorbent assay inhibition test. The core of the epitope in humans, monkeys and mice was 124KWVNGREI131. CONCLUSION: We found that 124KWVNGREI131 is an important B cell epitope recognized by IgE in humans, monkeys and mice.     

Existence of exine-free airborne allergen particles of Japanese cedar (Cryptomeria japonica) pollen

We investigated whether exine-free pollen allergen particles exist together with the intact pollen grains of Japanese cedar (Cryptomeria japonica) in the air during the pollen season in Yamagata City. First, we separated the allergen particles in an Andersen multi-stage air-sampler according to their aerodynamic diameters. The amount of major allergen (Cry j I) on each stage of the sampler was determined by a sensitive fluorometric sandwich ELISA, and the pollen count of the same samples was done by light microscopy after Carberla staining. Cry j I was found in stages 1 to 6, whereas most of intact and ruptured pollen grains were microscopically observed only in stages 1 and 2. Second, we suctioned the air through a tandem membrane filter system (the first filter, Nuclepore filter with 5 microns-pores; and the second, Millipore filter with 0.3 micron-pores). None of the pollen grains was detectable on the 0.3 micron-pore filter with light microscopy. However, Cry j I was detectable in the aqueous extract from the second filter. From these results, we concluded that pollen-free Cry j I existed in the air of Yamagata City during the pollen season.     

The allergen profile of beech and oak pollen

Background Beech and oak pollen are potential allergen sources with a world‐wide distribution. Objective We aimed to characterize the allergen profile of beech and oak pollen and to study cross‐reactivities with birch and grass pollen allergens. Methods Sera from tree pollen‐allergic patients with evidence for beech and oak pollen sensitization from Basel, Switzerland, (n=23) and sera from birch pollen‐allergic patients from Vienna, Austria, (n=26) were compared in immunoblot experiments for IgE reactivity to birch (Betula pendula syn. verrucosa), beech (Fagus sylvatica) and oak (Quercus alba) pollen allergens. Subsequently, beech and oak pollen allergens were characterized by IgE inhibition experiments with purified recombinant and natural allergens and with allergen‐specific antibody probes. Birch‐, beech‐ and oak pollen‐specific IgE levels were determined by ELISA. Results Beech and oak pollen contain allergens that cross‐react with the birch pollen allergens Bet v 1, Bet v 2 and Bet v 4 and with the berberine bridge enzyme‐like allergen Phl p 4 from timothy grass pollen. Sera from Swiss and Austrian patients exhibited similar IgE reactivity profiles to birch, beech and oak pollen extracts. IgE levels to beech and oak pollen allergens were lower than those to birch pollen allergens. Conclusion IgE reactivity to beech pollen is mainly due to cross‐reactivity with birch pollen allergens, and a Phl p 4‐like molecule represented another predominant IgE‐reactive structure in oak pollen. The characterization of beech and oak pollen allergens and their cross‐reactivity is important for the diagnosis and treatment of beech and oak pollen allergy.     

Molecular and immunological characterization of a novel timothy grass (Phleum pratense) pollen allergen, Phl p 11

BACKGROUND: Allergy to grass pollen is typically associated with serum IgE antibodies to group 1 and/or group 5 allergens, and additionally often to one or several less prominent allergens. Most of the grass pollen allergens identified to date have been characterized in detail by molecular, biochemical and immunological methods, timothy grass being one of the most thoroughly studied species. However, a 20-kDa allergen frequently recognized by IgE antibodies from grass pollen allergics has so far escaped cloning and molecular characterization. OBJECTIVE: To clone and characterize the 20 kDa timothy grass pollen allergen Phl p 11. METHODS: Phl p 11 cDNA was cloned by PCR techniques, utilizing N-terminal amino acid sequence obtained from the natural allergen. Phl p 11 was expressed as a soluble fusion protein in Escherichia coli, purified to homogeneity and used for serological analysis and to study Phl p 11 specific induction of histamine release from basophils and skin reactivity in sensitized and control subjects. RESULTS: Phl p 11 cDNA defined an acidic polypeptide of 15.8 kDa with homology to pollen proteins from a variety of plant species and to soybean trypsin inhibitor. The sequence contained one potential site for N-linked glycosylation. Serological analysis revealed that recombinant Phl p 11 shared epitopes for human IgE antibodies with the natural protein and bound serum IgE from 32% of grass pollen-sensitized subjects (n = 184). Purified recombinant Phl p 11 elicited skin reactions and dose-dependent histamine release from basophils of sensitized subjects, but not in non-allergic controls. CONCLUSION: As the first representative of group 11 grass pollen allergens, Phl p 11 has been cloned and produced as a recombinant protein showing allergenic activity. One-third of grass pollen-sensitized subjects showed specific IgE reactivity to recombinant Phl p 11, corresponding in magnitude to a significant proportion of specific IgE to grass pollen extract.     

Isolation, cDNA cloning and expression of Lig v 1, the major allergen from privet pollen

Background An olive allergen-like protein has been detected in privet pollen. This protein could be involved in the allergenic cross-reactivity described for privet and olive tree pollen extracts. Objective Isolation and characterization of natural Lig v 1. Cloning and expression of its cDNA in order to assess its structural similarity with the olive allergen. Methods Current chromatographic methods were used to isolate the privet counterpart of Ole e 1. A pool of sera from subjects allergic to olive tree pollen was used to immunodetect the protein in the elution profiles. Ole e 1-specific polyclonal antibody and allergic sera were used in immunoblotting assays of the isolated protein, Polymerase chain reaction amplification of the first strand cDNA synthesized from the privet pollen total RNA was carried out to prepare a full-length fragment encoding Lig v 1. After nucleotide sequencing, expression of one clone was performed in Escherichia coli, under the form of a fusion protein with glutathione S-transferase. The IgE binding capability of the recombinant protein was also analysed. Results The major allergen from privet pollen, Lig v 1, was purified to homogeneity by two gel filtration chromatographies and one reverse-phase high-performance liquid chromatography. Its amino acid composition and N-terminal amino acid sequence were determined. Two different clones encoding Lig v 1 were sequenced. Strong sequence similarity between Lig v 1 and Ole e 1 was observed, the identity being 85 and 96%. One of the sequenced clones was expressed and the recombinant product exhibited IgG and IgE binding activities against both anti-Ole e 1 polyclonal antibodies and olive-allergic sera. Conclusion Privet pollen contains a protein structurally and immunologically related to the major allergen of ohve pollen. The similarity exhibited by these proteins could explain the cross-reactivity observed between the two pollen extracts. Since these allergens are highly polymorphic, the expression of an immunologically active recombinant Lig V 1 will permit the preparation of well defined molecules for both research and chnical purposes.     

Detection of airborne allergen (Ole e 1) in relation to Olea europaea pollen in S Spain

BACKGROUND: In recent years, it has been demonstrated that the air carries not only airborne pollen but also plant particles of smaller size that have allergenic activity, and, being within the respirable range, these particles can trigger rapid attacks in the lower respiratory tract. The study of particles according to size (0.7-40 micro m) could provide valuable information on the real allergenic activity in the atmosphere. OBJECTIVE: The purpose of this study was to analyse the dynamics of airborne Olea europaea pollen in contrast to the allergenic activity of Ole e 1 in the atmosphere. METHODS: The analyses were carried out with a Hirst-type volumetric collector and a cascade impactor simultaneously during the MPS of the olive. The indirect ELISA was used to detect the allergenic activity. The sampling was performed in Granada city centre (S Spain), in the Science Faculty building on the University of Granada from 30 April to 26 June 2005. RESULTS AND CONCLUSIONS: This research demonstrates that both the allergenic activity as well as the pollen particles follow in a similar curve, except in periods before or succeeding the main Olea pollen season. The study of the distribution of the allergenic particles according to their sizes reveals that the highest concentrations are between 3.3 and <0.7 micro m, thus indicating that allergenic activity primarily involves paucimicronic particles.