Comparison between two commercial immunoassays:Dr.Fooke ALLERG-O-LIQ versus Phadia ImmunoCAP~ System in detecting allergen-specific IgE and total IgE values

Objective:Beside patient's history and skin prick testing(SPT)the detection of specific IgE(sIgE)represents an important tool of allergy diagnostics.In recent years different technologies for the detection of sIgE have been developed.The objective of this study is the comparison of the ALLERG-O-LIQ with the ImmunoCAP System using seven inhalant and four food allergens.Methods:Sera from patients were collected and tested for sIgE to inhalant(d1,d2,d5,i6,e1,e5 and m3)and food allergens(f1,f2,f24,f24)by ALLERG-O-LIQ(Dr.Fooke Laboratorien GmbH)and by ImmunoCAP System(Phadia).Further,samples were also tested for total IgE in both systems.Results:Prevalence of positive test results varied between 0/20(f24)and 11/20(e5)for ALLERG-O-LIQ and between 3/18(f23)and 11/20(d1/d5)for ImmunoCAP .The qualitative agreement between both methods was found between 75%(f24)and 100%(d2)depending on the allergen.Overall qualitative agreement for inhalant(n=140),food(n=78)and all allergens(n=218)tested was 92.1%(kappa=0.84),83.3%(kappa=0.58),89.0%(kappa=0.77),respectively.Sensitivity,specificity,positive predictive value (PPV),negative predictive value(NPV)and diagnostic efficiency(DE)were found at 88.2%,95.8%,95.2%,89.6%,92.1%(inhalant allergens),62.5%,92.6%,78.9%,84.7%,83.3%(food allergens)and 81.5%,94.4%,91.5%,87.5%,89.0%(all allergens).Conclusion: Good to excellent qualitative agreement between ALLERG-O-LIQ and ImmunoCAP for the detection of specific and total IgE could be observed.The degree of agreement depended on the allergen and was higher in the group of inhalant allergens.The ALLERG-O-LIQ System represents a reliable test for the detection of specific and total IgE.     

Triclosan exposure and allergic sensitization in Norwegian children

Background Exposure to the synthetic antimicrobial chemical, triclosan, used in personal care products, has been hypothesized to lead to allergic disease. We investigated whether triclosan exposure was associated with allergic sensitization and symptoms in 10-yearold Norwegian children.Methods Urinary concentrations of triclosan were measured in one first morning void from 623 children, collected during 2001–2004.Logistic regression models, controlling for urine specific gravity, parental allergic disease, maternal education, and household income, were fitted for allergic sensitization (either skin prick test positivity or serum-specific IgE ≥ 0.35 kU/l to at least one of 15 evaluated inhalant and food allergens), current rhinitis, and current asthma (questionnaire and exercise challenge test).Results The adjusted odds ratio (aOR) for allergic sensitization among those in the fourth quartile of triclosan concentration was 2.0 [95% confidence interval (CI): 1.1, 3.4] compared with the reference group (the limit of detection), and the aOR per log10 unit increase in triclosan was 1.2 (95% CI: 1.0, 1.4). The aOR for current rhinitis was 1.9 (95% CI: 1.1, 3.4) for the fourth quartile and 1.2 (95% CI: 0.97, 1.4) per log10 unit increase in triclosan.Conclusion Triclosan concentrations were associated with allergic sensitization, especially inhalant and seasonal allergens, rather than food allergens. Current rhinitis was associated with the highest levels of triclosan, whereas no association was seen for current asthma.These results are consistent with recent findings in other studies and provide additional evidence for an association between triclosan and allergy.     

Allergen micro-array detection of specific IgE-reactivity in Chinese allergy patients

Background  Allergen micro-arrays are powerful tools for screening of serum IgE-reactivity. In this study allergen micro-arrays were used to identify dominating IgE-binding allergens and cross-reactivity patterns among selected Chinese allergy patients.

Methods  The study was conducted using patient sera from the cities of Guangzhou, Nanjing, Chengdu and Shenyang. In total 100 sera with Dermatophagoides pteronyssinus (Der p) specific IgE-levels higher than 50 kU/L were selected for testing against 103 individual allergens.

Results  Among 100 selected patients, 95% showed IgE-reactivity towards house-dust mite allergens Dermatophagoides farinae (Der f) 1, Der f 2 and Der p 2 and 94% were IgE positive against Der p 1, and 60% of sera contained IgE reacting against allergen Euroglyphus maynei (Eur m) 2. IgE against cat allergen, Felisdomesticus (Fel d) 1, was seen in 20%. Only 2% showed specific IgE-reactivity to Der p 10, a panallergen belonging to the tropomyosin family. Serum IgE-reactivity towards other allergens was in general low. IgE-reactivity against pollen allergens showed geographic differences.

Conclusions  This study clearly confirms that group 1 and group 2 are major allergens of house dust mites. These selected house-dust mite allergy patients are close to being mono-sensitized. Der p 10 is not an important allergen for cross-reactivity. Specific IgE-sensitization towards pollen allergens is low in southern China compared to other regions. The prevalence of food and stinging insect allergens known to give rise to IgE-mediated cross-reactivity is 2% or less.

     

Analysis of Allergens in 5 473 Patients with Allergic Diseases in Harbin,China

Objective To analyze the allergic status to common inhalant allergens and food allergens in clinical patients in Harbin in northeastern China and provide evidence to develop the prevention strategy of allergic disease. Methods The data were collected from 5 473 patients with clinical suspected allergic diseases seeking medical care in the Second Affiliated Hospital of Harbin Medical University. Among these patients, 2 530 （46.2%） were males aged 0-86 years, the youngest was only 1 month old and 2 579 （47.1%） were young children and teenagers. The serum specific Immunoglobulin E （slgE） to 14 kinds of common allergens and serum total IgE were detected by using AllergyScreen test （Mediwiss Analytic GmbH, Moers, Germany）. Results In 5 473 subjects the positive rate of slgE was 33.1% （n=1 813）. Cow milk （6.9%） and wheat （3.1%） were the most common food allergens, followed by house dust mite mix （12.5%） and mould mix （9.4%） and the age and gender specific differences in the positive rate were significant. For the children aged 〈7 years the positive rates to cow milk, beef-mutton, and egg white/egg yolk were high, but the positive rates to house dust mite mix, ragweed estragon, and mould mix were low （P〈0.05）. For the adults the positive rates to aeroallergens were high while the rates to food allergens were low. Conclusion The results from this study showed that the food allergens in Harbin had geographic characteristics, which support the viewpoint that the environment factors play an important role in the incidence of allergic diseases. Also, the detection of slgE and total IgE are essential to identify relevant allergens for the purpose of early diagnosis, management and prevention of allergic disease.     

复合过敏原：过敏诊断和治疗的重要变化

The cloning and production of allergens through the use of DNA technology has provided the opportunity to use these recombinant proteins instead of natural allergen extracts for the diagnosis of IgE-mediated allergic disease: The conventional tests are based on allergen extracts composed of a mixture of both allergenic and non-allergenic components. Knowledge of the individual IgE reactivity profile may be used in selecting patients for specific immunotherapy with vaccines based on allergen extracts and, in the near future, recombinant allergen vaccines. Finally, evaluation of serum allergen specific IgG4 induced by conventional subcutaneous immunotherapy can serve to evaluate the allergen content of the alergen extract employed, a few weeks after the onset of immunotherapy, and to monitor patient‘s specific immune response.     

Comparison of Human Papillomavirus Detection and Genotyping with Four Different Prime Sets by PCR-Sequencing

Objective To assess and compare the Human Papillomavirus(HPV) detection efficiency and the potential clinical utility of PCR sequencing‐based technology.Methods Four HPV consensus primer sets(GP5+/6+,MGP,MY09/11,and PGMY09/11) were used in order to amplify a broad spectrum of HPV types for HPV infection in 325 cervical samples and the PCR products were sequenced afterwards for the HPV genotyping.Results The HPV‐positive rate was 75.4%,of which 35.5% harbored more than one HPV genotype.A total of 36 different genotypes was found,with HPV 16(24.1%) being the most prevalent,followed by HPV 58(13.3%) and HPV 52(9.6%).There were substantial to almost perfect agreements between different primer sets regarding HPV detection efficiency,with the kappa value varying from 0.751 to 0.925,MGP,and PGMY09/11 were the most effective in detecting multiple infections(P<0.001).With each of the primer sets,a board range of HPV types could be identified,though there were several differences for a few genotypes.Conclusion The substantial agreement between PCR‐sequencing and HC2 for the detection of high‐risk HPV(kappa=0.761) indicated that PCR‐sequencing is also suitable for routine HPV screening.     

Enrichment-ELISA for detection of Salmonella typhi from food and water samples

Objective Development of monoclonal antibody based sandwich enzyme linked immunosorbant assay （sELISA） for rapid detection of Salmonella enterica serovar typhi （S. typhi） from food and water samples and optimization of enrichment procedures for use with the developed sELISA to increase the detection sensitivity of the assay. Methods Spleen cells from BALB/c mice immunized with flagellin （H=d） antigen of S. typhi were fused with Sp2/0 myeloma cells. The hybridoma cell line specific to H=d antigen was established, characterized and ascites raised against one of these clones. The hyperimmune serum to flagellin antigen was raised in New Zealand White rabbits. An sELISA was developed using polyclonal antibody as capture and monoclonal antibody as detection antibody. To design the efficient culture strategies for use with the sELISA, different pre-enrichment and enrichment broths were evaluated. The media included buffered peptone water （BPW） and brain heart infusion broth for pre-enrichment and selenite F broth and Rappaport-Vassiliadis broth as enrichment broths. The developed sELISA with preceding enrichment step in BPW （Enrichment-ELISA） was evaluated in various food samples artificially inoculated with S. typhi bacteria. Various food （30） and water （35） samples collected from field were also tested by Enrichment-ELISA and culture method. Results Out of four specific clones to H=d antigen, one clone （# 2/56, IgG2a isotype） was used in sELISA. The sELISA had the detection limit of 10^4-10^5 cfu of S. typhi. Of the various broths used with sELISA, BPW was found to yield maximum ELISA values. Enrichment-ELISA, when tested in artificially inoculated food samples, generally, could detect 10^2 S. typhi cfu/mL within 10 h from various food rinses （meat, vegetable） and milk samples. After overnight enrichment in BPW, as less as 2 bacteria per 10 mL of milk, meat rinse, and chicken rinse could be detected. Only one of the field samples （water） gave false positive result by Enrichment-     

HOUSE DUST MITE ALLERGEN （Derp1 AND Blot5） LEVELS IN ASTHMATICS＇ HOME IN HONGKONG

Objective To measure Derpl and Blot5 allergen levels in asthmatics' homes in Hongkong.Methods Seventy houses were enrolled for a mite indoor environment study. Dust samples were obtained from two sites of each patients' house: bed and floor. Derpl and Blot5 levels were quantified by a two-site monoclonal antibody-based ELISA technique.Results The levels of Derpl allergens found in bed (geometric mean (GM) 3.43 μg/g of dust; 95%CI, 1.89-4.96 μg/g)and on the floor (GM 1.12 μg/g of dust; 95%CI, 0.71-1.53 μg/g) indicated significant differences (P=0.005). However, the levels of Blot5 allergens found in bed (GM 19.00 μg/g of dust; 95%CI, 0.89-38.90 μg/g) and on the floor (GM 6.14 μg/g of dust; 95%CI, 0.40-11.90 μg/g) showed no statistically significant difference. In addition, in regards to the exposure index for Derpl and Blot5 allergens found in bed and on the floor, 17.6% in bed and 8.6% on the floor had levels of Blot5 ≥ 10 μg/g of dust, higher than those obtained for Derp1 (7.2% and 0% in bed and on the floor respectively, P＜ 0.05); higher percentages in bed and on the floor (25.0% and 35.7%) were observed for levels of Blot5 =0 μg/g of dust as compared with Derpl in bed and on the floor (4.3% and 14.5% respectively, P＜ 0.05).Conclusions Derpl and Blot5 are the major allergens found in this regional study, Blot5 is a more potent allergen in Hongkong, probably reflecting the high level of exposure to Blomia tropicalis (Bt). Bt and Dermatophagoides pteronyssinus (Dp) allergens should be included for precise diagnosis and effective immuno-therapeutic treatment of mite allergy in Hongkong.     

EFFECTS OF SDS, PBS SOLUTIONS UPON FLUORESCENCE VALUES OF DERMATOPHA GOIDES PTERRONYSSINUS RADIOALLERGOSORBENT TEST INHIBITION

Objective To explore the effects of SDS, PBS re-dissolvent solutions on fluorescence values of radioallergosorbent test (RAST) inhibition. Methods Dermatophagoides pterronyssinus allergen immunoCAP and UniCAP 100 System were used. The Sera Pool consisted of 20 Dermatophagoides pterronyssinus allergic patients sera, their specific IgE fluorescence values were between 12 505 and 24 776. Results Fluorescence value percentages decreased: 62.9%, 54.1%, 43.5%, 6.7%, 3.7%, 2.6%, 2.2%, and 1.4% respectively, when SDS concentrations were at 2%, 1%, 0.5%, 0.25%, 0.1%, 0.05%, 0.025%, and 0.01%. Fluorescence values decreased more than 5% with SDS concentrations equal to 0.25% or higher. PBS in 0. l and 0.01 mol/L concentrations decreased fluorescence values 2.9% and 0.9% respectively. Conclusions SDS is a commonly used surfactants in allergen extract and re-dissolvent prepared allergen precipitation for RAST inhibition. Thus effects of surfactants (e.g. SDS) upon the RAST inhibition tests must be considered when they were used as re-dissolvent agents to improve protein resolution in RAST inhibition.     

Indoor Allergen Levels and Household Distributions in Nine Cities Across China

Objective Chinese allergic subjects have high levels of sensitization to house dust mite (HDM) and other indoor allergens. This study quantifies common indoor allergen levels in Chinese households.
Methods Dust samples were collected from nine cities. Major allergens Der p 1 and Der f 1 from Dermatophagoides pteronyssinus and D. farinae, and specific antigens of Blomia tropicalis, Tyrophagus putrescentiae, Acarus siro, and cockroach species Blattella germanica and Periplaneta americana were measured by ELISA.
Results HDM allergens were found in dust samples from bedding in 95% of the Chinese households. The median levels varied from <0.006 to 9.2 μg/g of dust, depending on the city. The percentages of households having HDM allergen levels associated with the risk of developing allergy sensitization and asthma were 65% and 25%, respectively. Specific antigens of the storage mite and cockroach were only found in samples from the southern and tropical regions of China. Levels of mite allergens were generally higher in samples from bedding compared to samples from the living room, even for storage mites, whereas levels of cockroach antigens were higher in the living room samples.
Conclusion HDM allergens are present in bedding dust samples from most Chinese households. Cities in southern and central China have relatively high levels of HDM major allergens compared to cities in northern and western China. Antigens of storage mites and cockroaches are not as common as HDM allergens.     

哮喘儿童血清总IgE、尘螨特异性IgE检测分析

目的研究儿童过敏性哮喘与血清总IgE、尘螨特异性IgE、尘螨过敏原皮肤点刺试验的关系.方法采用双抗体夹心酶联免疫吸附试验(ELISA),检测了87例哮喘患儿血清总IgE和尘螨特异性IgE水平,应用国际标准方法做尘螨过敏原皮肤点剌试验,并比较了三种检查结果之间的关系.结果哮喘患儿的血清总IgE为(542.84+321.85)IU/ml,尘螨特异性IgE阳性率为71.3%,尘螨过敏原皮肤点刺试验阳性率83.9%,正常对照组42名健康儿童总IgE(221.76±213.73)IU/ml,尘螨特异性IgE阳性率19.0%,皮肤点刺试验阳性率23.8%,三种试验两组间统计学处理有极显著差异(P＜0.01);血清总IgE增高(＞450IU/ml)与尘螨特异性IgE阳性符合率91.5%;血清尘螨特异性IgE阳性与皮肤点刺试验阳性符合率为75.6%.结论哮喘儿童血清总IgE水平、尘螨特异性IgE阳性率及尘螨皮肤点刺试验阳性率均明显高于健康儿童.     

豚鼠IgE提取与生物学特性鉴定

本文用马血清免疫豚鼠,获得高IgE含量血清。经饱和硫酸铵盐析,DE-52纤维素层析和Sephadex G-200凝胶过滤连续纯化,提取了豚鼠IgE纯品,并进行了鉴定。提取过程中用反向间接血凝法代替被动皮肤过敏反应(PCA)追踪检测IgE。所获IgE免疫家兔后,产生的抗血清能有效地触发豚鼠耳肿反应。     

小儿喘息性疾病血清总免疫球蛋白E和特异性免疫球蛋白E变化研究

目的 探讨血清总免疫球蛋白E(tIgE)和特异性免疫球蛋白E(sIgE)在小儿喘息性疾病诊断中的价值.方法 采用酶联免疫吸附法及欧蒙印迹法检测80例喘息性疾病患儿和80例体检健康儿童血清tIgE和sIgE水平,并进行比较.结果 喘息性疾病组患儿tIgE水平和sIgE阳性率较对照组均明显升高,差异有统计学意义(P＜0.05).80例喘息性疾病患儿中,tIgE升高54例,其中有过敏症状的仅38例.结论 喘息性疾病与IgE关系密切,联合检测血清tIgE和sIgE能够提高小儿喘息性疾病的检出率.     

反复呼吸道感染患儿血清总IgE和特异性IgE水平

目的：测定反复呼吸道感染（RRTI）患儿血清总IgE（tIgE）水平、特异性IgE（sIgE）阳性率,探讨RRTI与血清tIgE、sIgE的关系。方法：RRTI患儿40例,对照组健康儿童35例,采用酶联免疫吸附（ELISA）法检测血清tIgE水平,欧蒙印迹法检测血清吸入与食物组抗原sIgE抗体阳性率。结果：（1）RRTI组血清tIgE水平比对照组显著升高（P〈0.01）;（2）RRTI组血清吸入与食物抗原sIgE类抗体阳性率比对照组明显升高（P〈0.01）;（3）RRTI组血清sIgE类抗体以抗尘螨组合、猫毛、屋尘抗体多见,而食物组sIgE类抗体则以抗海鱼和淡水鱼抗体多见;（4）sIgE阳性率在tIgE水平升高与否的两组间差异不具显著性,血清tIgE水平升高率在sIgE阳性与否的两组间差异亦不具显著性（P〉0.05）。结论：RRTI可能与过敏体质有关,tIgE水平的升高或降低与sIgE阳性率高低并不完全一致。     

流行性出血热病人血清中IgE和IgE免疫复合物的检测

本文应用ELISA法检测了EHF病人血清中IgE及IgE免疫复合物。结果表明,各病日组病人血清中IgE和IgE免疫复合物的含量显著地高于正常人。IgE水平以3～5病日者为最高。IgE免疫复合物以6～10病日者为最高。6～10病日者IgE免疫复合物的沉淀指数为86.5%。     

变应性鼻炎患者血清特异性IgE及总IgE测定118例分析

目的了解变应性鼻炎疾病特异性过敏原及血清总IgE水平变化。方法采用酶筛分析法(AllergyScreen)对118例变应性鼻炎患者的血清过敏原及总IgE水平进行了检测。结果118例变应性鼻炎患者中吸入组过敏原以以屋尘螨粉、尘螨(62/118)为最高,其后依次为猫毛皮屑、狗毛皮屑(35/118)、矮豚草、蒿(14/118)、蟑螂(12/118)、柏榆、梧桐、柳三角叶杨(8/118)、律草(7/118)、点青霉、分枝孢霉、烟曲霉、交链孢霉(6/118);食入组过敏原以牛肉、羊肉(13/118)为最高,其后依次为腰果、花生、黄豆(11/118)、小麦(10/118)、牛奶(9/118)、鱼虾蟹(5/118)、芒果(4/118)、鸡蛋白、鸡蛋黄(1/118);总IgE阳性率为35.59%。结论血清过敏原及总IgE酶筛分析可以帮助临床合理寻找相应过敏原,为变应性鼻炎的预防、诊断和治疗提供依据。     

830例过敏性皮肤病血清总IgE和过敏原特异性IgE检测报告

目的:总结及分析过敏性皮肤病血清过敏原检测结果,探讨本地区过敏性皮肤病与年龄、性别、季节的关系及过敏原种类分布特点。方法:采用日本HITACHI公司试剂和CLA1过敏原分析仪对830例过敏性皮肤病患者进行血清总IgE和35种过敏原特异性IgE检测。结果:830例患者36项试验有一项以上阳性者553例,阳性率66.63%,35种过敏原试验有一种以上阳性者134例,阳性率16.14%,其中2岁～15岁年龄组35种过敏原试验阳性率27.45%,而>15岁年龄组35种过敏原试验阳性率14.56%,两组比较差异有显著性。阳性率较高的过敏原是粉尘螨、屋尘螨、家尘、青霉菌属和蘑菇。结论:血清总IgE和过敏原特异性IgE检查,对预防和治疗过敏性皮肤病具有重要参考意义。     

过敏性疾病血清总IgE和过敏原特异性IgE检测的临床意义

目的探讨血清总IgE(TIgE)和过敏原特异性IgE(sIgE)检测在过敏性疾病中的意义。方法采用全自动过敏原体外检测系统UniCAP100检测660例过敏性疾病患者血清TIgE,吸入性过敏原过筛试验(Phadiatop)及食物过敏原过筛试验(fx5E)测定sIgE水平。结果 17～84岁组TIgE水平明显高于0～3岁组与4～16岁组(P<0.05),660例过敏性疾病患者TIgE总阳性率为93.0%(614/660),其中465例(75.73%)TIgE>100kU/L。sIgE总阳性率为65.76%(434/660),吸入与食物过敏原均阳性者102例,其中92例TIgE>100kU/L。0～3岁组食物过敏原阳性率较另外两组显著增高(P<0.01),4～16岁组和17～84岁组吸入性过敏原阳性率增高(P<0.05)。吸入性过敏原Ⅳ～Ⅵ级阳性率明显高于食物性(P<0.005)。结论采用荧光酶联免疫法进行过敏原体外检测,不仅可以预示过敏体质,还可以查找过敏原因,为过敏性疾病的诊断和治疗提供帮助。     

婴幼儿哮喘患者血清RSV-IgE及尘螨特异性IgE检测

检测３８例婴幼儿哮喘患者、２０例健康儿血清呼吸道合胞病毒特异性ＩｇＥ（ＲＳＶ－ＩｇＥ）及尘螨特异性ＩｇＥ。结果：ＲＳＶ－ＩｇＥ阳性率在哮喘患儿为４７．４％，健康儿为５％（Ｐ＜０．０１）；尘螨特异性ＩｇＥ阳性率在哮喘患儿为２６．３％，健康儿为５％（Ｐ＜０．０５）。提示在大多数婴幼儿中病毒感染诱发的哮喘占主要地位，而少部分患儿对尘螨过敏，须引起重视。因此，避免或控制尘螨及病毒感染，可减轻发作期症状，延长缓解期，将有助于防止发展成典型的儿童哮喘。