抗人gp130分子单克隆抗体的制备和鉴定

ｇｐ１３０可与许多细胞因子受体（ＩＬ－６Ｒ,ＩＬ－１１Ｒ,ＯＳＭＲ,ＬＩＦＲ,ＣＮＴＦＲ和ＣＴ－１Ｒ）组成受体复合物,并在这类细胞因子的信号转导中的起着重要的作用。方法以痘苗病毒为载体构建获得的可溶性ＣＤ１３０（ｓＣＤ１３０）为免疫原,通过融合的方法。得到４株稳定分泌抗ＣＤ１３０单克隆抗体（ｍＡｂ）Ｌ２,Ｌ４ａ,Ｌ４ｂ和Ｌ５）的杂交瘤细胞株。结果本组ｍＡｂ对靶细胞具有识别特异性,不但可识别相对分子     

从半合成噬菌体抗体库中筛选抗角蛋白人抗体

目的：从半合成噬菌体抗体库中筛选人源性抗角蛋白抗体并进行鉴定。方法：以表皮角蛋白为抗原,通过吸附－洗脱－扩增过程从半合成噬菌体抗体库中筛选特异性抗角蛋白抗体,对其抗原结合活性的序列进行分析鉴定。结果;经过４轮筛选,获得２０个能与角蛋白结合的阳性克隆,其中可产生特异性抗角蛋白抗体的克隆１８个。经ＤＮＡ指纹分析,判断所获克隆分别包含４个不同的Ｆａｂ段基因。     

嵌合抗CD20抗体Fab片段在大肠杆菌中表达及活性鉴定

目的 :构建抗CD2 0 嵌合抗体Fab片段表达载体 ,并在大肠杆菌中进行高效可溶性分泌表达。方法 :利用PCR方法从抗CD2 0 单链抗体 (ScFv)表达载体上扩增抗CD2 0 抗体轻链可变区基因 (VL)、重链可变区基因 (VH) ,然后将VH、VL 基因重组到Fab表达载体pYZF中 ,构建抗CD2 0 Fab表达载体pYZF1cd2 0 ,并在 2 7C7菌中高效表这。结果 :经Fab表达载体转化的 2 7C7菌株 ,进行表达培养 ,经分离纯化获得具有CD2 0 特异结合活性的Fab片段 ,竞争性免疫荧光抑制实验表明 ,表达产物Fab片段能竞争性抑制鼠源性抗CD2 0 抗体HI47和CD2 0 表达细胞Raji细胞结合。结论 :在大肠杆菌中高效可溶性分泌表达有活性的抗CD2 0 嵌合抗体Fab片段。     

Shortening of the diagnostic window with a new combined HIV p24 antigen and anti-HIV-1/2/O screening test

Because antibodies to the human immunodeficiency virus (HIV) are absent in the very early phase of HIV infection, there remains a slight residual risk for HIV transmission by blood donations by viremic but antibody negative donations. To shorten the diagnostic window between infection and the detection of antibodies, Enzygnost® HIV Integral (Dade Behring, Germany) was developed. With this new test, HIV p24 antigen and HIV antibodies can be detected simultaneously in a single test. In a multicenter study the new screening assay has been compared with various tests that detect only HIV antibodies or HIV p24 antigen and with assays which permit a simultaneous detection of HIV antigen and HIV antibodies. The new assay showed 100% sensitivity for the detection of antibodies to HIV-1, groups M (n=1102) and O (n=55), and HIV-2 (n=289). In 23 out of 52 seroconversion panels, seroconversion was detected 2–18 days earlier with the new combined antigen/antibody test compared to single antibody tests. All samples from a viral load panel (n=451), all samples containing p24 antigen (n=302), and all but one of the cell culture supernatants (n=38) infected with various HIV-1 subtypes or HIV-2 were identified reliably by the new test. The specificity of the assay for 4002 unselected blood donors was 99.78% initially and 99.80% after retesting. Potentially interfering factors had no systematic influence on specificity. By testing for p24 antigen, which is present prior to the onset of antibody production in some cases of recent HIV infection, the new assay reduces the diagnostic window as compared to third generation screening assays, thus permitting an earlier diagnosis of HIV infection.     

HCG滴金免疫测定法试剂的研制及应用

应用自制的两种抗人绒毛膜促性腺激素（ＨＣＧ）单克隆抗体、分别包被硝酸纤维膜及制备胶体金结合物,建立了检测ＨＣＧ的滴金免疫测定法。结果表明,本法简便、快速,灵敏度高（最小抗原检测量为５０ｍＩＵ／Ｌ）,特异性好,与高浓度的ＬＨ、ＦＳＨ、ＴＳＨ均无交叉反应,临床检验２１７例样品,与ＥＬＩＳＡ法对比测定的符合率为１００％。     

HIV-1 Nef protein inhibits the in vitro induction of a specific antibody response to Candida albicans by an early up-regulation of IL-15 production

We have previously demonstrated that exogenous Nef protein induced activation of normal human T cells up-regulating IL-15 production by monocytes. Since HIV-1 infection results in the early impairment of immune functions we decided to evaluate if Nef is able to modulate the induction of a specific antibody response. Human peripheral blood mononuclear cells from healthy donors were induced in vitro to mount a specific antibody response to the Candida albicans antigen. We show that Nef inhibited, in a dose-dependent manner, the induction of the anti-C. albicans antibody response. The ability of an anti-Nef antibody to prevent such inhibition indicates that the effect was indeed Nef-specific. In the Nef-treated cultures an early increase of IL-15 production was observed and the addition of anti-IL-15 antibody abrogated the Nef-induced inhibitory effect. Moreover the addition of IL-15 to the cultures inhibited, as well as Nef, the induction of the specific antibody response. Thus, our results suggest that Nef may inhibit the induction of a specific antibody response by an early up-regulation of IL-15 production. A better comprehension of this phenomenon may be important for unravelling some aspects of the B cell defects in HIV infection.     

兔抗重组人钙网蛋白抗体的制备及其特性鉴定

目的:制备兔抗人钙网蛋白抗体并进行特性鉴定。方法:用PCR法扩增人钙网蛋白(CRT)基因,并克隆至pET32a表达载体中。以重组质粒pET32a/hCRT转化大肠杆菌BL-21(DE3),用IPTG诱导重组蛋白的表达,通过Ni2+-NTA琼脂糖凝胶柱亲和层析纯化目的蛋白。以纯化的hCRT为免疫原免疫新西兰大白兔制备抗体,用ELISA法、Westernblot和免疫组化染色法检测抗体的效价和特异性。结果:成功地表达并纯化hCRT重组蛋白。以纯化的重组hCRT免疫新西兰大白兔制备的抗体,ELISA检测其效价为1∶51 200,Western blot分析显示,该抗体能与hCRT特异性结合。免疫组化染色法检测结果表明,该抗体能识别天然的hCRT。结论:以重组hCRT为免疫原,成功地制备效价高、特异性好的兔抗hCRT抗体,为进一步进行钙网蛋白的检测及其临床应用研究奠定了基础。     

抗Ⅳ型登革病毒NS1单克隆抗体的制备及特性鉴定

目的:研制Ⅳ型登革病毒(DENV-4)非结构蛋白1(NS1)特异性的单克隆抗体(mAbs),并鉴定其特异性。方法:在表达具有良好抗原性的重组DENV4-NS1蛋白的基础上,用重组DENV4-NS1蛋白和灭活的DENV-4免疫BALB/c小鼠,取免疫小鼠的脾细胞与小鼠骨髓瘤细胞进行融合,用间接ELISA法筛选阳性的杂交瘤细胞,并结合免疫荧光测定法(IFA)和Western blot分析对mAb的特异性进行鉴定;通过竞争抑制试验对mAb识别的抗原位点进行分析。结果:获得15株特异性针对DENV4-NS1的mAbs,与其他3型DENV的NS1不产生交叉反应。mAb的Ig亚类测定均为IgG1。竞争抑制试验显示,15株mAbs存在2个不同识别抗原位点。结论:成功地获得特异性针对DENV4-NS1蛋白的mAbs,为进一步研究DENV4-NS1蛋白的结构与功能及研制DENV-4的临床诊断试剂奠定了基础。     

鲢鱼小清蛋白的分离纯化及其单克隆抗体的制备与鉴定

目的:制备抗鲢鱼主要过敏原小清蛋白的单克隆抗体,并对其基本特性进行鉴定。方法:采用硫酸铵盐析、离子交换柱层析和凝胶过滤柱层析等方法纯化鲢鱼小清蛋白;以纯化的小清蛋白免疫BALB/c小鼠,采用杂交瘤技术制备抗鲢鱼小清蛋白单克隆抗体;通过ELISA法确定抗体亚型;通过腹水诱生法大量制备单克隆抗体;以Protein G Sepharose亲和层析柱纯化制备的单克隆抗体;运用Western blot鉴定单克隆抗体的特异性;以ELISA法分析单克隆抗体的结合位点。结果:从100 g鲢鱼肌肉中可获得约30 mg高纯度小清蛋白;SDS-PAGE结果表明,得到的抗小清蛋白单克隆抗体(A4-C1)纯度较高,亚类为IgG1;Western blot结果显示,A4-C1只与鱼肉粗提物中的小清蛋白产生反应,特异性良好;ELISA分析表明,制备的抗鲢鱼小清蛋白单克隆抗体与商品化抗蛙小清蛋白单克隆抗体(PARV-19)的结合位点可能具有很大部分的重叠,或者存在较大的空间位阻效应。结论:研究中制备的杂交瘤细胞株能稳定分泌高特异性的抗鲢鱼小清蛋白单克隆抗体,可用于后续淡水鱼类小清蛋白检测方法的建立。     

肠道病毒71抗原ELISA检测方法构建及其应用

目的 建立肠道病毒71型(EV71)抗原的ELISA检测方法.用于EV71的抗原定量、TCID50试验及EV71免疫原性与免疫保护性的关系分析.方法 以高亲和力的EV71中和单抗K8G2和Y8H2-HRP构建检测EV71抗原的双抗体夹心ELISA方法.比较本方法与显微镜观察法检测的EV71 TCID50.分析EV71抗原的特异比活与免疫血清中和抗体水平的关系.结果 本试剂定量检测抗原的线性范围为0.125 ～4.0 U/ml,R2 =0.9911,试剂不与EV71之外的受试物反应,试剂的回收率为0.89 ～ 1.16,变异系数小于15％,37℃9 d的热回收率大于85％.本法与显微镜观察法检测的EV71 TCID50的相关系数r=0.990.21株EV71抗原的特异比活与免疫血清中和抗体水平的相关系数r=0.930.结论 构建了EV71抗原ELISA检测试剂,可用于EV71的抗原含量检测、TCID50分析,为特异比活与免疫血清中和性关系研究提供了一些有价值的信息.