EHF病毒感染家兔后血清特异性抗体水平的动态观察

本文报告了流行性出血热病毒(Epidemic haemorrhagic fever virus,EHFV)J10、A9株分别感染实验家兔后,用反向间接ELISA(RIELISA)和间接免疫荧光(IFA)方法,动态观察了家兔特异性IgG抗体水平的变化。发现特异性IgG于感染后第1周开始出现,以后抗体水平稳步上升,于第5—7周便达到最高水平,高滴度的抗体可以维持较长时间。结果还表明;RIELISA检测家兔抗体的敏感性明显优于IFA法。用IFA进行的交叉反应还证实;EHFV-J10、A9两种毒株的抗血清能与不同来源的数株病毒发生特异性结合反应。     

呼吸道疾病患儿血液中EB病毒IgM抗体及病毒DNA感染的临床分析

目的 分析呼吸道疾病患儿血液中EB病毒IgM抗体(EBV-IgM)及病毒DNA(EBV-DNA)感染情况.方法 对2013年3月至2016年3月我院收治的呼吸道疾病患儿578例的临床资料进行统计分析.结果 578例患儿中,28例患儿血清EBV-IgM阳性,176例患儿EBV-DNA阳性,阳性率分别为4.8％和30.4％.患儿的血清EBV-IgM阳性率显著低于EBV-DNA阳性率(P＜0.05);男性和女性患儿的血清EBV-IgM和EBV-DNA感染率之间的差异均不显著(P＞0.05);年龄为3-6岁患儿的血清EBV-IgM和EBV-DNA感染率均显著高于其它年龄组(P ＜0.05);1-3月份患儿的血清EBV-IgM和EBV-DNA感染率均显著高于其它时间段(P＜0.05).结论 呼吸道疾病患儿血液中EBV-IgM比EBV-DNA感染率低,二者感染率受到患儿年龄及季节影响,与性别无关.     

2014年北京地区成人呼吸道感染常见病原体IgM抗体检测分析

目的 探讨北京地区成人急性呼吸道感染(ARI)患者9种常见病毒的感染情况,分析病原体流行病学特征.方法 采用ELISA法检测1887例ARI患者巨细胞病毒(CMV)、EB病毒(EBV)、柯萨奇病毒(CVB),单纯疱疹病毒Ⅰ型和Ⅱ型(HSV-Ⅰ和HSV-Ⅱ),腺病毒3、7和11型(ADV3、ADV7和ADV11)及风疹病毒(RV)等9种病原体IgM抗体.结果 1887例标本中共检出阳性706例,总感染率为37.41％(706/1887),其中CMV感染率最高为10.92％,其次为HSV-Ⅰ(9.59％),其它病原体检出率由高到低依次为ADV7、ADV11、EBV、ADV3、HSV-Ⅱ、CVB和RV.混合感染者有260例,占36.83％ (260/706).10月份感染率最高,4月份感染率最低,且各病原体的流行季节也不同.病例以中青年感染者居多,不同性别间感染率差异无显著性.结论 2014年北京地区存在多种病原体流行,以CMV、HSV-Ⅰ和ADV7为主要病原体,各病原体流行有季节性特点.     

EHF患者血清IgM抗体反应的动态观察及其与病情的关系

流行性出血热(EHF)一类的疾病已被证实在世界范围内流行,特别是在中国等东亚国家流行甚广,病情严重。对于其发病机理,国内学者作了大量研究工作,提出异常的免疫反应为其致病机制之一。但是,在特异性体液免疫与病情的直接关系问题上,尚未有系统的研究报道。本文采用一种新的ELISA-IgM检测方法对60例新     

孕妇和新生儿血清中的巨细胞病毒特异性IgM抗体

应用间接ＥＬＩＳＡ方法检测了兰州地区７５７例孕妇和６２４例新生儿血清中巨细胞病毒特异性ＩｇＭ抗体（ＣＭＶ－ＩｇＭ）。孕妇组阳性者７４例（９．７８％），其中妊娠早期阳性者１９例，妊娠中期阳性者４４例，妊娠晚期阳性者１１例。新生儿组阳性者９例（１．４４％）。实验结果显示：兰州地区孕妇中有一定数量的ＣＭＶ活动性感染病例，以致伴有新生儿ＣＭＶ先天性感染。     

检测肺炎衣原体血清IgM抗体ELISA的建立和应用

特异性抗体测定是目前诊断肺炎衣原体(Chlamydia pneumoniae,C.pn)感染较敏感的方法.主要外膜蛋白(MOMP)是C.pn重要的抗原成分,具有良好的免疫原性,与C.pn的感染密切相关,其特异性抗体具有免疫保护作用[1].机体感染C.pn后体内可出现特异性的IgM抗体,检测该IgM抗体可作为判断C.pn感染的标志.本研究利用特异性的MOMP抗原,建立检测血清中C.pn特异性IgM抗体的ELISA[2],以351例病原学确诊的临床血清标本和11例其他病原体感染的肺炎患者血清标本为对照,对其灵敏度和特异性进行了评价,现报告如下.     

过敏性紫癜患儿血清呼吸道病毒感染特异性IgM及炎症因子检测及临床意义

目的 检测过敏性紫癜患儿血清呼吸道病毒感染特异性免疫球蛋白M(IgM)及炎症因子的表达水平,分析其与过敏性紫癜发生的关系.方法 选取2020年2月至2021年2月在本院住院治疗的70例过敏性紫癜患儿为过敏性紫癜组(春夏季、秋冬季各35例),同期选取在本院进行常规体检的健康儿童70例作为对照组(春夏季、秋冬季各35例)....     

抗猪IgM单克隆抗体的研制

随着规模化养猪业的发展，我国已相继出现多种新的猪传染病，包括猪繁殖与呼吸综合征、副猪嗜血杆菌和猪圆环病毒Ⅱ型感染等，并已引起严重的经济损失。研制抗猪IgM单抗来检测这些疫病特异性IgM型抗体，将为该疾病早期诊断提供新且简便的途径。近年来研究发现抗原特异性B细胞有高效抗原递呈作用，其膜表面抗原受体对抗原的摄取、浓缩和处理起着重要作用。用抗猪IgMμ链McAbs和抗体．抗原的McAbs组成的双特异性抗体，既能与抗原特异性结合，又能与B细胞膜表面抗原结合，从而能进一步在体内外从分子水平上研究B细胞抗原递呈特点，并且为显著降低疫苗接种剂量，提高机体免疫能力的探索提供新的实验手段。鉴此，本实验室用PEG融合技术，研制出分泌抗猪IgM μ链McAbs杂交瘤细胞株。     

血清抗心磷脂抗体阳性孕妇的临床观察

目的　探讨抗心磷脂抗体 (ACA)阳性的初次妊娠孕妇与不良妊娠的关系。方法　用ELISA法 ,采用结合指数的方法选取ACA阳性初次妊娠孕妇 138例为研究组 ;ACA阴性初次妊娠孕妇 10 0例为对照组 ,2 0周起进行随访观察。结果　在研究组中出现早产 4例 (2 9% )、妊高征 5例 (3 6 % )、流产 18例 (13% )、低出生体重儿 8例 (5 8% )、胎儿宫内发育迟缓(IUGR) 16例 (11 6 % )、死胎 6例 (4 3% )。另外在ACA阳性产妇的新生儿血中有 4例ACA -IgG阳性。对照组中出现流产2例 (2 % )。研究组与对照组比较有极显著性差异 (P <0 0 0 1)。结论　ACA阳性与不良妊娠有关 ,应对孕妇做ACA的常规检测 ,以利于尽早作出预防和治疗。     

治疗性抗体在病毒感染性疾病中的应用

抗体用于感染性疾病的治疗具有久远的历史。随着抗体技术的发展,从最初的鼠单克隆抗体(m Ab),经过嵌合抗体、人源化抗体的阶段,发展到现在的人抗体。抗病毒m Ab可以通过中和作用抑制病毒增殖或者通过抗体依赖细胞介导的细胞毒作用(ADCC)、抗体依赖的胞吞作用(ADCP)、补体依赖的细胞毒作用(CDC)和抗体依赖细胞介导的病毒抑制作用(ADCVI)发挥作用,还可通过诱导内源性体液和细胞免疫发挥长期保护效应。针对急、慢性病毒感染的m Ab的数量呈指数级增长,其中部分正在进行临床试验。针对病毒变异的问题,采用多种抗体联合使用的抗体鸡尾酒疗法。     

血清IgM、CRP在新生儿窒息及窒息后感染时的变化

目的检测新生儿窒息及窒息后感染时血清中IgM、CRP的变化及意义。方法采用免疫比浊法检测，测定血清IgM、CRP含量。结果新生儿窒息IgM含量降低与对照组比较有非常显著的差异，P〈0．01；感染组IgM含量降低与对照组比较有十分显著差异，P〈0．01；感染组与窒息组比较IgM含量无明显差异，P〉0．05；新生儿窒息CRP含量增高与对照组比较有非常显著差异P〈0．01；感染组CRP含量明显增高，与对照组比较增高明显，P〈0．05；感染组与窒息组比较有明显差异，P〈0．05。结论CRP、IgM联合检测对新生儿窒息及窒息后感染早期诊断有重要意义。     

ELISA for specific anti-toxoplasma IgM antibodies: aspects related to serum interference

Two different methods were used to prepare solid-phase antigen (Ag) from soluble extracts of tachyzoites of Toxoplasma gondii: (A) physical adsorption on polystyrene beads; and (B) formaldehyde fixation of Ag previously dried in microtitration wells. In both cases a horseradish peroxidase conjugate with anti-IgM IgG was used as tracer. The assay scheme consisted of sequential incubations of diluted serum samples and tracer solution (1 or 2 h, 37 degrees C), colour development in the presence of substrate (10 min at room temperature), addition of H2SO4, and absorbance reading at 492 nm. In procedure A no cut-off value for positives could be determined owing to a large overlap between positive and negative sera. The extent of overlap directly correlated with the total IgM content of samples. With negative sera similar values were obtained with sensitized and untreated beads: thus a correction could be made by directly subtracting absorbance values determined in parallel runs with uncoated beads. Results with negative sera correlated with total IgM concentration in procedure B also, but much less variability of blank values allowed negative and positive sera to be effectively discriminated. A series of reference positive and negative sera was correctly classified by both procedures A and B. However, the latter appeared preferable, as not requiring blank correction.     

Measles IgM antibodies in cerebrospinal fluid and serum in subacute sclerosing panencephalitis

Using a direct enzyme-linked immunosorbent assay (ELISA), we examined serum and cerebrospinal fluid (CSF) from six patients with subacute sclerosing panencephalitis (SSPE) and control subjects for presence of measles-virus-specific IgM antibodies. All samples from the SSPE patients contained demonstrable titers of measles antibodies. The levels of measles IgM antibodies were higher in CSF diluted 1:5 than in serum diluted 1:50, reflecting a local production of IgM antibodies in the central nervous system. Antibody titers remained constant over the course of SSPE in three of the patients followed for three to six months. The IgM ELISA had high sensitivity as well as specificity and was not complicated by false-positive reactions owing to the presence of rheumatoid factor.     

Complexes between HBsAg and IgM in serum of patients with acute hepatitis

HBsAg bound to IgM was measured in the serum of HBsAg carriers with acute hepatitis using a radioimmunoassay based on selective absorption of IgM on solid phase coated with antiserum to human IgM. HBsAg/IgM was detected in 94 (100%) patients with acute type B hepatitis during the acute phase of infection and persisted after the fourth week only in 13 of them, who developed chronic liver disease. HBsAg/IgM was detected only in 1 patient out of 15 carriers of the HBsAg with superimposed non-B hepatitis. No activity was found in serum of 20 patients with acute HBsAg-negative hepatitis. The nature of the IgM component of the complex is uncertain, however, blocking experiments of the HBsAg/IgM reaction with polymerized human albumin suggest that the IgM component of the complex might represent antibody to the denatured protein. Persistent HBsAg/IgM complex detection in patients with acute type B hepatitis provides a useful tool to predict transition of HBV infection to chronicity. Its absence in patients with acute HBsAg-positive hepatitis is indicative of non-B hepatitis in chronic carriers of the HBsAg.     

Rapid separation of IgM from whole serum using spun column chromatography

Spun columns were used to separate IgM from serum samples by exploiting molecular weight and size difference between IgM and other serum antibodies. Miniature gel chromatography columns were prepared in 3 ml syringe barrels. A polyacrylamide liquid chromatography gel, Bio-Gel P-200, was chosen to exclude proteins with molecular weights greater than 200,000. IgM, 900,000 MW, was excluded while IgG, 150,000 MW, was retained in the gel column. Centrifugation of the serum-loaded columns in test tubes accomplished the separation in one step by eluting a void volume equal to the sample volume from each column into a holding tube. IgM recovery in the eluent exceeded 96% of the total serum IgM in the pre-column sample. No IgG was detected in the eluent. IgM separated from La Crosse encephalitis immune human serum retained immunological activity in a viral neutralization test. Spun column chromatography is eminently suitable for diagnostic laboratories as more than 100 sera may be fractionated in one day using inexpensive materials and a low-speed centrifuge equipped with a swinging-bucket rotor.     

High frequency of false positive IgM immunoblots for Borrelia burgdorferi in Clinical Practice

Although it is known that two-tier serologic testing for Lyme disease may be associated with false positive results on the IgM immunoblot, this problem has never been systematically studied in the clinical practice setting. In a retrospective investigation of patients referred to the private adult practice of an Infectious Diseases physician for possible for Lyme disease, 50 of 182 patients (27.5%, 95% CI: 21.1-34.6) were found to have a false positive IgM immunoblot. 78.0% of these patients had received unnecessary antibiotic therapy. False positive results were not restricted to any single commercial laboratory. Research on alternative testing strategies that eliminate the IgM immunoblot entirely is warranted.     

Specificity and sensitivity of the IgM capture immunoassay: studies of possible factors inducing false positive or false negative results

The specificity and sensitivity of the IgM-capture immunoassay (IgM-CI) were evaluated for detection of rubella specific IgM and hepatitis B core (HBc) specific IgM. For rubella specific IgM, antibodies bound to the solid phase were detected by haemadsorption and for HBc specific IgM, by using HBc antigen (HBcAg) and radiolabelled IgG anti-HBc. Rheumatoid factor (RF) was found to interfere in the test for HBc specific IgM because IgM-RF bound to the solid phase reacted with aggregated radiolabelled HBc specific IgG. This false positive reaction did not occur when radiolabelled F(ab')2 was used instead of the whole IgG molecule. HBcAg purified from biological fluids might be coated with host IgG and under these conditions, HBcAg could react with RF. It was also demonstrated that high levels of IgG antibodies could interfere with IgG anti-mu coated-surface by means of non-immunological protein-protein interactions. In fact, IgG did not interfere in the rubella assay, whereas it did in the very sensitive anti-HBc test. To prevent this false-positive reaction, different dilution media were tested. Only the addition of non-specific IgG and fetal calf serum (FCS), to the dilution medium, seems to improve the specificity of the test. Furthermore, in order to decrease this non-specific IgG-IgG interaction and an occasional prozoning phenomenon, the dilution of serum to be tested was taken into account. Parameters considered to decrease sensitivity were also studied. RF, anti-F(ab')2 antibodies and non-specific IgM did not decrease significantly the sensitivity of the assay.     

柯萨奇B组病毒IgM抗体特性研究

目的 研究柯萨奇B组病毒（CVB）感染后患者急性期CVB－IgM抗体的反应特性。方法 对临床确诊为CVB感染的患者急性期血清用免疫印迹法检测CVB－IgM抗体。结果 患者的急性期血清IgM抗体均仅针对CVB的VP1抗原反应。经ELISA与免疫印迹方法的比较表明：用免疫印迹法检测的CVB－IgM抗体可对CVB各型病毒抗原反应,具有CVB各型病毒之间的交 叉反应性。而同时,在16例ELISA检测反应阴性的健康人血清中未见有CVB的VP1特异性的IgM抗体存在。结论 临床感染CVB的患者急性期,其血清中的特异性的IgM抗体是针对CVB的VP1抗原,而且,此类抗体对各型的CVB抗原具有交叉反应性。     

Detection by ELISA of IgA and IgM antibodies in secretion and IgM antibodies in serum in primary lower respiratory syncytial virus infection

Twenty-six infants and children with primary lower RS virus infection, diagnosed by the detection of RS virus in nasopharyngeal secretion (NPS) by use of immunofluorescent antibody (FA) technique, were studied with respect to the presence of IgA and IgM antibodies. Samples of NPS and serum obtained during the first 3-4 months following the beginning of illness, were investigated. Employing a reverse ELISA technique, we found IgM antibodies in the acute, but not during the convalescent, phase of illness in NPS from 20 of the patients and in serum from 21 of the patients. The majority of the IgM antibody conversions observed occurred in NPS as well as in serum on days 5-8 following the illness. RS virus IgA antibodies, also detected by a reverse ELISA technique, were demonstrated in NPS in 22 of the patients, with antibody conversions being found in 19 of the patients on days 5-8 following the beginning of the illness. Two patients still had IgA antibodies in NPS approximately 3 months FSOI. By comparison, RS virus was detected in acute-phase NPS by double-antibody sandwich ELISA in 25 of the 26 patients investigated.