人促黄体生成素光激化学发光免疫分析法的建立

目的采用光激化学发光免疫分析技术建立快速定量检测人促黄体生成素（hLH）的方法。方法用2株配对的hLH单克隆抗体,1株hLH单克隆抗体包被受体微球,另1株hLH单克隆抗体先用生物素标记,再与链霉亲合素的供体微球共同组成人促黄体生成素光激化学发光免疫分析试剂,进而优化反应体系并对试剂的各项性能指标进行评价。结果自制hLH试剂分析灵敏度为0.164 U/L,线性测量范围为0.164～135 U/L,分析内和分析间的精密度分别为4.3%～6.1%和7.4%～8.1%,均低于10%,与hTSH、hFSH和hCG无明显交叉反应,158份临床血清样本用本试剂与罗氏电化学发光检测试剂盒平行检测,对所测数值采用配对t检验分析,结果显示两种方法检测结果差异无统计学意义（t=-1.468,P=0.07）。结论自制hLH光激化学发光免疫分析试剂各项指标均能达到临床要求,有望替代国外同类产品。     

癌胚抗原光激化学发光免疫分析法的建立

目的:利用光激化学发光免疫分析技术(Al-phaLISA)建立人血清癌胚抗原(CEA)的快速检测试剂。方法:1株CEA单克隆抗体(mAb)包被受体微球,另1株(mAb)用生物素标记,与链霉亲和素的供体微球共同组成检测试剂,优化反应体系并对试剂的各项性能指标进行评价。结果:自制CEA试剂分析灵敏度为0.11 ng/mL,线性测量范围为0.11～500 ng/mL,分析内和分析间的精密度分别为3.3%～6.8%、5.5%～8.1%,与AFP、CA12-5、CA19-9和人血清白蛋白均无交叉反应,100份临床血清样本用本试剂与罗氏化学发光试剂检测,其相关系数为0.976。结论:自制CEA Al-phaLISA试剂的各项性能指标均能达到临床检测要求,有望替代国外同类试剂应用于临床血清样本CEA浓度的测定。     

胰岛素光激化学发光免疫分析法的建立

目的建立血清中胰岛素(INS)光激化学发光免疫分析的定量检测方法。方法用2株配对的INS单克隆抗体,一株INS单克隆抗体包被受体微球,另一株INS单克隆抗体用生物素标记,与链霉亲合素的供体微球共同组成检测试剂检测人血清中的INS。结果 INS-AlphaLISA的灵敏度为0.753μU/ml,线性测量范围为0.753～180μU/ml,分析内和分析间的精密度分别为7.46%～9.74%、5.24%～7.31%,与C肽无明显交叉反应、与胰岛素原有轻微交叉反应,125份临床血清样本用本试剂与罗氏化学发光试剂检测,其相关系数为0.983。结论本法建立的INS-AlphaLISA是一个各项指标均能达到临床要求的、可靠的检测,有望替代国内外同类产品用于临床。     

神经元特异性烯醇化酶光激化学发光免疫分析法的建立

研制检测人血清神经元特异性烯醇化酶(NSE)的光激化学发光免疫分析(AlphaLISA)快速检测试剂盒。采用受体微球用一株NSE单克隆抗体包被,用生物素标记一株单克隆抗体,与链霉亲和素的供体微球共同组成检测试剂盒,优化反应体系并对试剂盒的各项性能指标进行评价。结果显示:自制NSE试剂盒灵敏度为0.149 ng/ml,线性范围为0.149~600ng/ml,分析内、分析间的精密度分别为3.7%~4.3%、3.9%~5.2%,与细胞角蛋白19片段(CYFRA21-1)、非神经元性烯醇化酶(NNE)均无交叉反应,154份临床血清样本用本试剂盒与罗氏化学发光试剂盒检测,其相关系数为0.979。发现自制NSE-AlphaLISA试剂盒的各项性能指标均能达到临床检测要求,可用于临床血清样本NSE浓度的测定。     

C肽光激化学发光免疫分析试剂盒的研制

目的:研制光激化学发光免疫分析技术(AlphaLISA)建立人血清C肽(C peptide)的快速检测试剂盒.方法:采用夹心法建立C peptide AlphaLISA试剂盒.结果:自制C肽试剂盒灵敏度为0.06ng/ml.,可测范围为(0.06～22)ng/ml.批内与批间的精密度分别为4.0%～4.8%,5.6%～...     

促红细胞生成素光激化学发光定量检测方法的建立及评价

采用棋盘滴定法,用针对EPO抗原的一个单克隆抗体及两个多克隆抗体,分别包被发光微球,与生物素化EPO配对组成反应体系,筛选出最佳抗体,进而确定最佳反应浓度,建立竞争模式的光激化学发光检测EPO的方法,绘制标准曲线并评价该方法。研究中采用SPSS19.0软件和ELISA Calc进行统计分析。该法检测的敏感性为0.03ng/ml,在0.03~30ng/ml范围内线性良好。批内变异系数和天批间变异系数分别为3.66%和4.13%,EPO浓度高达30ng/ml时无Hook效应。51例EPO增高及51例健康体检者EPO的测定结果与放射免疫法检测EPO比较具有良好的相关性(r=0.913),建立的参考范围为0.77~4.88ng/ml。成功建立的竞争模式的光激化学发光定量检测EPO的方法,在EPO检测中具有极好的应用前景,有助于EPO诊断试剂盒的研制。     

牛奶模拟样本中金黄色葡萄球菌肠毒素C含量的两种发光检测方法比较

目的 比较均相光激化学发光检测法(AlphaLISA)和磁微粒化学发光检测法(MP-CLIA)在检测牛奶模拟样本中金黄色葡萄球菌肠毒素C(SEC)含量的敏感性和精确性。方法 以山羊抗SEC多克隆抗体偶联受体微球、生物素标记的SEC单克隆抗体和链霉亲和素偶联的供体微球,构建AlphaLISA检测体系;以山羊抗SEC多克隆抗体偶联碱性磷酸酶、生物素标记的SEC单克隆抗体和链霉亲和素偶联磁珠,构建MP-CLIA检测体系。结果 AlphaLISA检测牛奶模拟样本中SEC含量的灵敏度为4.04 ng/L,变异系数(CV)为1.98%～9.82%; MP-CLIA的灵敏度为108.19 ng/L,CV为4.63%～20.40%。结论 与MP-CLIA相比,AlphaLISA检测牛奶模拟样本中SEC含量的敏感性和精确性更高。     

双标记AFP及Free-β-HCG时间分辨荧光免疫分析法的建立

目的：研制能同时检测人血清AFP和Free-β-HCG的双标记时间分辨荧光免疫分析（TrFIA）试剂盒。方法：铕（Eu3＋）标记抗AFP单克隆抗体,用钐（Sm3＋）标记抗Free-β-HCG单克隆抗体,采用双抗体夹心法建立AFP/Free-β-HCG双标记TrFIA试剂,对试剂的各项性能指标进行评价。结果：AFP分析灵敏度为0.1U/ml,分析内和分析间的精密度分别为1.2%～5.9%和2.8%～6.3%,检测试剂的测量范围为（0.1～500）U/ml;Free-β-HCG分析灵敏度为0.25ng/ml,分析内和分析间的精密度分别为1.5%～6.2%和3.5%～5.6%,检测试剂的测量范围为（0.25～200）ng/ml。孕妇血样用本试剂盒与进口的同类试剂盒同时检测,AFP和Free-β-HCG的相关系数分别为0.987、0.968,具有较好的一致性。结论：自制AFP/Free-β-HCG双标记TrFIA试剂盒的各项性能指标均能达到临床检测要求,可替代国外同类产品。     

AFP电化学发光免疫分析方法的建立

目的建立一种快速、特异、灵敏的检测人甲胎蛋白（AFP）的电化学发光免疫分析法。方法用链霉亲和素包被的磁性微粒、生物素标记的抗AFP单克隆抗体、钌复合物标记配对的抗AFP单克隆抗体组成AFP电化学发光免疫分析法试剂,在电化学发光免疫分析仪上对其准确性、灵敏度、特异性等效能进行方法学评价,同时用所建方法与进口的同类电化学发光免疫分析法试剂（Roche）对80例肝癌患者血清AFP检测结果进行相关性分析。对218名健康志愿者血清AFP进行了正常值调查。结果自建电化学发光免疫分析法检测AFP的批内精密度在2.8%～4.5%之间,批间精密度在3.2%～9.8%之间,分析灵敏度为0.605ng/ml。与进口同类试剂比较,直线回归方程为y=0.9936x-0.4566（r=0.9877,P〈0.05）。分析测量范围为0.605～1452.0ng/ml,自建试剂与CEA和CA199无交叉反应。自建电化学发光免疫分析法检测AFP的正常参考值为〈6.7ng/ml。结论自建AFP电化学发光免疫分析法特异性高,灵敏度好,与进口同类试剂检测结果相关性达0.9877。确定的实验室正常参考范围接近进口同类试剂,具备产业化的潜能。     

促甲状腺素光激化学发光免疫测定法的建立和初步应用

采用光激化学发光免疫测定法(LICA)技术建立促甲状腺素(TSH)快速定量检测方法。采用两株针对TSH不同表位的单克隆抗体,一株单抗包被发光微粒,另一株为生物素化单抗,两者与链亲和素包被的感光微粒一起构建双抗体夹心LICA。数据处理采用双对数函数处理程序。方法的灵敏度为0.015mIU/L;批内CV为2.5%～3.6%,批间CV为2.6%～4.4%;平均回收率为100.60%。与时间分辨荧光免疫分析法(TRFIA)比对,相关系数达0.9681;与TRFIA临床测定值呈明显相关;正常值范围为0.33～3.09mIU/L。本文建立的TSH光激化学发光免疫测定法是目前TSH检测中最快速灵敏的方法之一,该方法稳定性好,具有很好的应用前景。     

HLA antibody identification with single antigen beads compared to conventional methods

Single antigen (SA) beads coated with Class I HLA antigens from recombinant cells lines were tested with 170 mouse monoclonal antibodies (mAbs). The HLA specificities of all mAbs were previously determined by the cytotoxicity assay (CDC). There were 100 mAbs which produced the expected reactions with the SA beads, indicating that the SA beads coated with the antigens had reacted properly. Sixty one mAbs were positive with one or more antigen(s) that shared unique amino acids (aa) possibly constituting a common epitope. Single antigen beads were then tested on 58 alloantisera analyzed by 63 laboratories of the UCLA serum exchange (UCLA-SE). Many specificities detected by the single antigen beads were missed by the laboratories employing conventional methods. Most of the missed specificities were of lower frequency, although in some instances, even common specificities were missed. These findings have important implications regarding the use of specificities to predict positive crossmatch, to selecting platelet donors for highly sensitized recipients, and analysis of sera for donor specific antibodies.     

Flow cytometric detection of HLA antibodies using a spectrum of microbeads

We describe here the use of HLA antigen coated beads for specificity and class determination of HLA antibodies by flow cytometry. The HLA specificity of antibodies was determined by use of beads containing eight levels of fluorescence. HLA antigens isolated from eight cultured cells were coated onto these beads so that each bead was the equivalent of one cell. By using four sets of eight beads, an equivalent of 32 cells could be examined in four test tubes. A total of 76 class I and 25 class II specificities could be determined by the 32 class I bead-panel and 32 class II bead-panel used, respectively. We noted no cross-reactivity of reactions between class I and II. The sensitivity of the test was shown to be higher than that of the standard cytotoxicity by dilution experiments and detection of additional cross-reacting antigens. By use of these coated beads, we achieved improved standardized detection of HLA antibodies. Antigen-coated beads have several advantages over the use of spleens or lymphocytes. (a) A highly selected panel of antigens can be routinely used. (b) Class I and class II antibodies can be readily distinguished from each other, even when they are present as mixtures in one serum. (c) Non-HLA antibodies are not detected because the beads do not have any other antigens than HLA on them. (d) The quantity of antigens coated on beads is more uniform than that found in cells from different individuals. (e) Beads are more convenient for storage and daily use.     

Hydroxyapatite-coated nylon beads as a new reagent to develop a particle agglutination assay system for detecting Japanese encephalitis virus-specific human antibodies.

BACKGROUND: Detection of Japanese encephalitis virus (JEV)-specific antibodies is done today by hemagglutination-inhibition assay (HIA), neutralization assay (NTA) and enzyme-linked immunosorbent assay (ELISA). These conventional assays are often difficult to perform in diagnostic laboratories with insufficient resources. An alternative antibody detection kit, which is simple, preservable and inexpensive, is needed for extended use in rural areas of Asia. OBJECTIVES: (i) Characterization of a new antigen carrier, hydroxyapatite-coated nylon (Ha-Ny) beads, and (ii) evaluation of the JEV antigen-coated Ha-Ny beads as a reagent to detect anti-JEV antibodies in human serum samples. STUDY DESIGN: We examined the Ha-Ny beads for hydroxyapatite content, precipitation efficiency and protein adsorption ability. We then developed a particle agglutination assay system using the JEV antigen-coated Ha-Ny beads, and tried out the newly developed assay system with reference serum samples. RESULTS: The beads had the ability to adsorb 0.44 mg of lysozyme per gram. Sedimentation speed was 10.2 cm/30 min in phosphate buffered saline (PBS), pH 7.0. Binding of the JEV antigen on Ha-Ny beads was confirmed by scanning electron microscopy (SEM) and ELISA. Eighteen confirmed-human serum samples were tested by the newly developed particle agglutination assay system. The results were consistent with those from HIA, NTA and ELISA. CONCLUSION: The Ha-Ny beads can be applicable to the development of a new JEV antibody-detection kit, which does not require specific laboratory facilities.     

Subclass distribution of rubella virus-specific immunoglobulin G

An enzyme-linked immunosorbent assay was used to study the subclass distribution of rubella virus-specific immunoglobulin G (IgG) in 97 serum samples from healthy donors and from patients with recent or remote rubella infections. Plastic beads coated with rubella antigen were incubated with test serum and then with monoclonal antibodies to the four human subclass of IgG. Rubella virus-specific IgG1 was present in all serum samples containing rubella virus-specific IgG antibodies. Rubella virus-specific IgG2 was present in 1 of 35 samples from healthy donors that also contained specific IgG1. Rubella virus-specific IgG3 was found in serum samples from patients with recent rubella infections but had disappeared by 6 months after the onset of symptoms. Rubella virus-specific IgG4 was found in low amounts in 7 of 35 samples from healthy immune donors. Of 20 serum samples that were negative by other serological techniques, 8 gave absorbances above cutoff levels in the assays for rubella virus-specific total IgG and IgG1. In 1 of 20 serum samples, the assays for total IgG and IgG2 were positive. High absorbance in the assay for rubella virus-specific IgG4 was found in one serum. This serum was negative in all other assays for rubella virus-specific antibodies.     

Solid-phase radioimmunoassay of serum immunoglobulin A antibodies to respiratory syncytial virus and adenovirus.

A solid-phase radioimmunoassay for detecting respiratory syncytial virus and adenovirus serum immunoglobulin A (IgA) antibodies was developed. An antigen consisting of purified adenovirus type 2 hexons or a crude lysate of respiratory syncytial virus-infected cells was first adsorbed onto polystyrene beads. The coated beads were then incubated with dilutions of serum, and IgA antibodies which attached to the solid-phase virus antigen were subsequently detected with 125I-labeled anti-human alpha antibodies. The anti-human alpha antibodies used were isolated by immunosorbent chromatography from rabbit antiserum produced by immunization with IgA purified from serum of an IgA myeloma patient. A total of 46 serum specimens from 13 patients with respiratory syncytial virus infections and 10 patients with adenovirus infections were tested. Complement fixation, homologous IgG and IgM radioimmunoassay, and heterologous IgA radioimmunoassay testing were also done. Specific values higher than 10,000 cpm were often reached with convalescent serum specimens, and positive-to-negative serum binding ratios of 50 or more were frequently obtained with lower serum dilutions. IgA titers of convalescent sera were from 1,000 to 16,000, and with few exceptions a fourfold or greater rise in the IgA titer was detected in the homologous IgA radioimmunoassay.     

HLA class I epitopes: recognition of binding sites by mAbs or eluted alloantibody confirmed with single recombinant antigens

Development of beads coated with single recombinant HLA antigens has permitted the confirmation and further definition of HLA class I epitopes. In this study, monoclonal antibodies (mAbs) or alloantibodies eluted from recombinant cell lines were tested for reactivity with Luminex beads individually coated with 79 recombinant HLA class I single antigen (rHLA SA). Published amino acid sequences were used to map epitopes common to sets of antigens reactive with each antibody. While several epitopes have already been demonstrated, this study confirmed them by adsorption of allosera with transfectants or SA beads having a single HLA antigen and specific binding of the eluted antibody on SA beads. The allosera and mAbs used in this study recognized a total of at least 58 HLA class I epitopes, as demonstrated by their different adsorption/reactivity patterns. Of these, 25 epitopes were characterized by a single unique common amino acid, 30 shared 2 signature amino acids in close proximity, and 3 epitopes involved 3 specific amino acids in a non-linear sequence. Since these epitopes may be targets for antibody-mediated allograft rejection, epitope analysis should complement HLA and CREG assignment for defining complex antibodies and identifying suitable donors for highly sensitized transplant patients.     

A Rapid Method for Selecting Specific Hybridoma Clones using Paramagnetic Dynabeads®

This paper describes how specific hybridoma clones can be rapidly selected using paramagnetic beads coated with the antigen used for immunization. Spleen cells from a mouse immunized with fragment D dimer (DD) from plasminolysed fibrin were first fused with X-63 mouse myeloma cells. Paramagnetic monodisperse beads (precoated with sheep anti-mouse antibodies) were then coated with S4, a monoclonal antibody to DD, and subsequently with DD, Mixing such beads with the fused cells allowed selective harvesting of cells with membrane-expressed anti-DD gammaglobulins using a magnetic particle concentrator. Within 24 h, the cells spontaneously detached from the beads and were plated out on 96-well plates. Supernatants from the clones obtained were tested by the ELISA technique. Antibodies specific for DD were produced by 40–79% of the tested clones. It is concluded that it is possible to use antigen-coated paramagnetic beads to select, prior to cloning, hybridomas that produce specific antibodies. Implementation of this technique has significantly reduced costs and time in our efforts to obtain hybridoma clones of interest.