Evaluation of a recombinant antigen enzyme-linked immunosorbent assay (ELISA) in the diagnostics of antinuclear antibodies (ANA) in children with rheumatic disorders

The reliability and accuracy of ELISAs for the detection of circulating ANA in children with rheumatic diseases has recently been questioned. In this study we evaluated an allegedly superior ELISA method using recombinant antigens in a paediatric population with various rheumatic conditions and compared it to a conventional Hep-2 IFA assay. Sera from 123 children (204 blood samples) were simultaneously tested by conventional ANA immunofluorescence on Hep-2 cells (ANA-IFA) and recombinant antigen ELISA (rELISA). There were 44 children with systemic lupus erythematosus (SLE), 29 with juvenile rheumatoid arthritis (JRA), eight with mixed connective tissue disease (MCTD), eight with reactive arthritis, five with juvenile fibromyalgia syndrome, three with dermatomyositis (JDMS) and 31 with other diagnoses.  Thirty-five children (27%) had a positive Hep-2 result, which remained undetected by ELISA (P <0.002). Almost all of these children had significant IFA titres above 1:160. The major discrepancies were observed in children with JRA and SLE. There was no titre correlation between the two assays and the rELISA’s OD readings were not linear.  The ELISA using recombinant antigens was not useful for the detection of serum ANA in children with rheumatic diseases due to a high rate of false negative results. These data concur with recent reports about the lack of reliability of ELISAs using non-recombinant antigens. Received: 2 May 2001 / Accepted: 10 September 2001     

湖南首次发现斑点热

目的　研究湖南是否存在斑点热感染。方法　采用间接免疫荧光抗体法（ＩＦＡ）检测两县林区工人斑点热感染阳性率。结果　两县林区工人感染阳性率为２０００％ ,其中宜章县阳性率为２０３７％ ,平江县阳性率为１９２０％ ;蜱类调查中除有二棘血蜱、越原血啤和微小牛蜱外,新发现有龟形花蜱;经鉴定鼠类有２３ 种。结论　宜章、平江两县林区工人存在斑点热今后需继续从病人、媒介昆虫、宿主动物分离病原体。     

1996～1997年江西省南昌地区流感监测

为了监测流感动态确定优势病毒株,在江西省南昌地区进行了流感病毒分离和鉴定研究。从1996年5月～1997年4月共采取感冒病人鼻咽拭子1440份,全部用双腔接种法接种鸡胚,部分标本又进行细胞培养。采用血凝抑制试验（HAI）鉴定病毒株的型及亚型,对细胞培养获得的20株病毒同时应用间接免疫荧光试验（IFA）鉴定病毒株的型别,取HAI法检测为甲型的任意20株进行多聚酶链反应（PCR）试验。结果：共分离得流感病毒47株,其中,甲1型（H1N1）26株,占55．32％;甲3型（H3N2）10株,占21．28％;乙型（B）11株,占23．4％,优势流行株是甲1型,发现了甲1、甲3、乙型在同一地区同时流行的现象,也发现了“O”相毒株。因流感病毒的变异均局限在量变范围内,预计短期内没有大流行的危险。IFA法PCR试验结果全部与HAI法一致,故结论可靠,IFA、PCR法也是快速准确鉴定流感病毒的好方法。     

Fire ant venom hypersensitivity. I. Comparison of fire ant venom and whole body extract in the diagnosis of fire ant allergy

Levels of IgE antibody to fire ant whole body extract (FA-WBE) and fire ant venom (FAV) were evaluated in 60 patients with clinical histories of fire ant sting hypersensitivity and 11 frequently stung individuals without significant clinical reactivity to fire ant. An overlap of levels of IgE antibody to FA-WBE and FAV was seen between groups of patients with increasingly severe clinical reactivity; however, the group mean IgE antibody level of patients without significant clinical reactivity differed markedly from the group means of patients with more severe clinical reactivity (p less than 0.001). In 31 patients a good correlation (r = 0.6935) was found comparing FA-WBE IgE antibody level with FA-WBE skin tests, and in 26 patients a good correlation (r = 0.8564) was obtained comparing FAV IgE antibody levels with FAV skin tests. An excellent Spearman rank correlation coefficient (r = 0.9197) was found on comparison of FAV and FA-WBE IgE antibody levels in 71 individuals. Cross-reactivity of FAV and FA-WBE was demonstrated by the ability of these reagents to competitively inhibit the binding of IgE antibody to solid-phase FA-WBE and FAV in the radioallergosorbent test (RAST). From these results we conclude that FAV and FA-WBE both contain relevant allergens important in fire ant-allergic individuals and that skin tests and RAST are both valid as diagnostic tests for fire ant allergy. Finally, there is a good correlation between RAST and skin tests using FA-WBE or FAV as test reagents, since these reagents are highly cross-reactive as demonstrated by their ability to inhibit each other in the RAST.     

莱姆病诊断技术应用探讨

目的:探讨不同莱姆病诊断技术的灵敏度和特异度。方法:应用间接免疫荧光抗体法(IFA)、酶联免疫吸附试验(ELISA)、蛋白印迹法(WB)3种方法检测新疆123例疑似莱姆病患者血清及部分脑脊液抗伯氏疏螺旋体IgM、IgG抗体,其中3例PCR法检测尿液,结合相应的影像学、电生理检查诊断莱姆病。似然比方法计算灵敏度。结果:依据中国疾病控制中心制定的标准确诊莱姆病43例。其神经系统、皮肤损害、关节炎发生率分别为31·7%(39/123),1·62%(2/123),1·62%(2/123)。IFA、ELISA、和WB3种检验方法的阳性率分别为60·47%、48·84%、39·53%。用似然比方法计算灵敏度:IFA为60·47%、ELISA为48·84%、WB为39·53%;联合灵敏度为79·60%;特异度均为100%。3例PCR均阳性。结论:应用IFA、ELISA和WB技术检测血清和脑脊液抗伯氏疏螺旋体抗体有助于临床诊断。     

利用菌落免疫荧光法鉴定对多种支原体起反应的单克隆抗体

我们用菌落免疫荧光染色技术对4株(3D_1、3A_(11)、3F_5、2E_5)抗精氨酸支原体(MycoPlasma arginini)McAb进行了鉴定,在热水固定的菌落上3D_1、3A_(11)不仅与精氨酸支原体出现了阳性反应,而且与口腔支原体(M.orale)、猪鼻支原体(M.hyorhinis)、莱氏无胆甾原体(AcholePlasma laidlawii)、羊无乳支原体(M.agalactia)PG_2和牛丝状支原体丝状亚种(M.mycoides subsp. mycoides)PG_1等均有交叉反应;在未固定的菌落上用表面免疫荧光检测时, McAb却表现了与PcAb不同的特性。同时我们还做了阻断试验,进一步证明了我们制备的McAb的支原体特异性。     

习惯性流产孕妇巨细胞病毒pp65抗原检测的临床意义

目的:探讨人巨细胞病毒(HCMV)活动性感染与习惯性流产(RPL)的关系。方法:采集习惯性流产孕妇和正常产前体检孕妇外周血,分离外周血单个核细胞(PBMCs)和血浆,分别用免疫荧光法和实时定量PCR检测HCMV pp65抗原和HCMV-DNA,并比较2种方法的一致性。结果:46例RPL患者HCMV pp65抗原有14例阳性,阳性率30.4%,50例正常体检孕妇HCMV pp65抗原有4例阳性,阳性率8%,2组孕妇HCMV活动性感染率有显著性差异(2χ=6.76,P<0.01)。孕妇HC-MV pp65抗原阳性率升高,孕妇流产几率增加(2χ=6.39,P<0.01)。免疫荧光法和实时定量PCR有较好的一致性(93.5%)。结论:习惯性流产孕妇HCMV活动性感染率显著高于正常孕妇,HCMV pp65抗原检测可作为RPL早期诊断指标之一。     

四川省狂犬暴露者疫苗免疫后血清抗体水平分析

目的：了解四川省狂犬病暴露者狂犬疫苗注射后血清抗体水平。结果：对四川省27个县（市、区）抽样采集狂犬病暴露者疫苗免疫后的血清用间接荧光免疫法进行检测。结果：753份血清中,抗体阳性率为87．91％,总的抗体几何平均滴度（GMT）为18．67。不同厂家产品、男女和各年龄组之间的抗本阳性率无显著性差异,而不同厂家和年龄段的抗体GMT值组间有显著性差异（F＝2．4225,P＜0．05;F＝3．492,P＜0．01）,以0－岁组最高,年龄越大越代。结论：开展常规的疫苗免疫后抗体检测,酌情增加抗体阴性者和老年暴露者的接种针次,以提高免疫成功率具有十分重要的意义。     

Role of goblet cells and mucin layer in protecting maternal IgA in precocious birds

Immune protection of the gut in early life depends on provision of maternal antibodies, particularly that of IgA. In precocial birds (in this study Gallus gallus domesticus) the egg provides the only source of maternal antibodies, IgA inclusive. The gut-life of IgA in hatchlings is expected to be brief due to antigen binding and intestinal washout, and maternal IgA is likely to be depleted prior to immune independence at 7–10 days of age in the domestic fowl. We followed the track of maternal IgA in mucosal surfaces of the fowl and describe for the first time a mechanism that might provide the means to extend the active period of maternal IgA in the gut. Maternal IgA was located in the gut, lung, and cloacal bursa in embryos and hatchlings prior to the appearance of endogenic IgA positive plasma cells (D3 in the bursa or D7 in the gut and lung); the source of IgA was most probably the yolk, as the plasma was devoid of IgA till D7 post-hatch. The levels of maternal IgA decreased with time, but were still easily determined at the onset of endogenous IgA production following maturation of the adaptive immune system. Persistence of maternal IgA in the gut was enabled by goblet cell up-take by a yet un-described mechanism, and its consequent release in a mucin-like layer on enterocyte apical surfaces.     

弓形虫性视网膜脉络膜炎

本文介绍了弓形虫性视网膜脉络膜炎16例,其中1例属多灶性与Coats病相似;余为局灶性,多与中心性、渗出性视网膜炎相似。血清抗体IHA均>1:80,并阐述了此病的临床特点及治疗方法,提出对可疑者应作特异血清抗体检查,以便确诊与及时治疗。