幽门螺杆菌尿素酶B单克隆抗体的制备与鉴定

目的:制备稳定分泌抗幽门螺杆菌尿素酶B单克隆抗体(mAb)的杂交瘤细胞系,并对其分泌的mAb进行鉴定。方法:用初步纯化的重组幽门螺杆菌尿素酶B免疫BALB/c小鼠,利用杂交瘤技术制备抗尿素酶B的mAb,用间接ELISA检测mAb的特异性和亲和力,检测mAb腹水效价,鉴定Ig亚类并测定其抗原决定簇。结果:获得8株能稳定分泌抗尿素酶B的mAb杂交瘤细胞系,这8株单抗与能产生尿素酶的小肠结肠耶尔森氏菌、肺炎克雷伯氏菌和普通变形杆菌均无交叉反应,相对亲和力为1.13×10-8～4.66×10-10,腹水mAb效价可达2×104～3.2×105。其中2株单抗属IgG1亚类,3株单抗属IgG2a亚类。8株单抗分属于3种不同的抗原决定簇。结论:获得了IgG1和IgG2a类型的针对3种不同抗原决定簇的特异性幽门螺杆菌尿素酶B的mAb,为进一步用于幽门螺杆菌的临床诊断和实验研究创造了条件。     

Detection of Helicobacter hepaticus in Human Bile Samples of Patients with Biliary Disease

Background:  Since the discovery of Helicobacter pylori , various enterohepatic Helicobacter spices have been detected in the guts of humans and animals. Some enterohepatic Helicobacters have been associated with inflammatory bowel disease or liver disease in mice. However the association of these bacteria with human diseases remains unknown.
Materials and Methods:  We collected 126 bile samples from patients with cholelithiasis, cholecystitis, gallbladder polyp, and other nonbiliary diseases. Samples were screened for the presence of enterohepatic Helicobacter spp. using cultures, nested PCR, or in situ hybridization. We tested for antibodies to H. pylori and H. hepaticus by Western blot analysis.
Results:  Attempts at cultivation were unsuccessful. However, H. hepaticus was detected in bile samples with nested PCR whereas H. bilis was not. Helicobacter hepaticus in the bile was confirmed by in situ hybridization, but H. hepaticus from bile samples was coccoid in appearance. We detected immunoglobulin G antibodies to H. hepaticus in bile samples by Western blotting. Helicobacter hepaticus was detected in 40 (32%) of total 126 samples as H. hepaticus positive if at least one of the three methods with nested PCR, in situ, or Western blotting. Patients with cholelithiasis (41%) and cholecystitis with gastric cancer (36%) had significantly higher ( p  = .029) prevalence of H. hepaticus infection than samples from patients with other diseases.
Conclusion:  Helicobacter hepaticus may closely associate with diseases of the liver and biliary tract in humans.     

Characterization of an Anti-Thioredoxin Monoclonal Antibody

An anti-E. coli thioredoxin monoclonal antibody, IMM-3C6, which showed high specificity to thioredoxin as assessed by indirect ELISA, was generated using hybridoma technology. The affinity constant of IMM-3C6 to thioredoxin was 0.40×10⁹ m⁻¹ and its sensitivity to thioredoxin fusion protein in dot blotting was 50 ng. In sandwich ELISA, it detected thioredoxin fusion protein between 16 and 150 ng/ml. By using IMM-3C6 as the ligand, thioredoxin fusion protein was successfully purified by affinity chromatography. IMM-3C6 was confirmed to be a useful tool for immunoassay and purification of thioredoxin fusion proteins. These authors contributed equally to the work. Received 21 September 2005; Revisions requested 7 October 2005; Revisions received 10 November 2005; Accepted 11 November 2005     

Genomic characterization of Helicobacter hepaticus: ordered cosmid library and comparative sequence analysis

Helicobacter hepaticus is an important pathogen in laboratory mice and induces the development of liver tumors and gastrointestinal disease in susceptible strains of mice. In this study, a miniset of 36 cosmid clones from a genomic library of H. hepaticus was ordered and grouped into four large contigs representing approximately 1 Mb of the H. hepaticus genome using PCR, DNA sequencing, Southern and dot-blot hybridization and pulsed-field gel electrophoresis. From the 200-300 terminal nucleotide sequences of 38 cosmid clones, 56 coding regions were predicted, of which 51 were found to have orthologs in the public databases and five appeared to be unique to H. hepaticus. Of these 51 genes, 36 have orthologs in Helicobacter pylori and 25 display the highest sequence similarity to H. pylori. However, chromosomal positions of these genes are not conserved between these two helicobacters. In addition, 10 H. hepaticus genes had the highest sequence similarity to orthologs in Campylobacter jejuni. The GC content in a randomly selected 21-kb H. hepaticus genomic sequence was 35.8%, which approximates the average between H. pylori (39%) and C. jejuni (30.6%). These results demonstrate that: (1) H. hepaticus is more closely related to H. pylori than C. jejuni; (2) significant genomic alterations exist between H. hepaticus and H. pylori, including gene organization, protein sequences and GC content, probably in part due to specific adaptation to distinct ecological niches.     

基于抗CD20单克隆抗体的2种夹心ELISA法的建立

目的:建立和比较2种灵敏、特异的夹心ELISA方法,用于准确定量检测食蟹猴血浆中重组抗CD20人源化单克隆抗体(rh-anti-CD20zumab)浓度。方法:以rh-anti-CD20zumab为基础,分别用山羊抗人IgG F(ab')2抗体和驴抗人IgG Fc抗体包被96孔酶标板,加入待测样品,均采用HRP标记的猴血清吸附的山羊抗人IgG抗体进行检测,加底物显色,读取D450nm值。结果:建立了2种定量检测rh-anti-CD20zumab的夹心ELISA方法并进行了确证,样品的前处理分别为1∶20和1∶10,方法的线性范围分别为40~5000和40~12 500 ng/mL,定量下限均为40 ng/mL,两者的板内、板间精密度分别小于16.2%和19.4%,准确度分别为-10.3%~16.6%和-14.4%~12.9%。2种方法均具有良好的特异性和稀释线性,且都未出现钩状效应。结论:方法学确证表明,本研究建立的2种ELISA法均符合新生物制品临床前药代动力学研究指导原则的要求,可用于rh-anti-CD20zumab的检测,为后续rh-anti-CD20zumab在食蟹猴体内的药代动力学研究提供了不同的检测方法。     

乙氧基磷酸酯类有机磷农药单克隆抗体的制备与鉴定

制备针对乙氧基磷酸酯类有机磷农药的单克隆抗体,以此为基础建立该类农药的快速免疫筛选检测方法．以二乙基磷酸乙酸为通用结构半抗原,分别使之与牛血清白蛋白和鸡卵清蛋白共价偶联,合成免疫原和包被原并对其进行结构鉴定．偶联成功后的免疫原用于免疫Balb/c小鼠．将免疫成功小鼠的脾细胞与小鼠SP2/0骨髓瘤细胞融合,筛选能稳定分泌抗乙氧基磷酸酯类有机磷农药单克隆抗体的杂交瘤细胞株．获得的小鼠腹水用辛酸-硫酸铵法纯化,所得纯化抗体以琼脂双扩散法鉴定其免疫球蛋白类型,间接竞争ELISA方法测定其对半抗原的灵敏度、特异性和亲和性．结果表明,该抗体分泌IgG1亚类的单克隆抗体,且与二乙基磷酸乙酸的亲和性较高(1.4×10⁷ L/mol),所得抗体对毒死蜱、对硫磷、丙溴磷、氧化乐果、除线磷、二嗪农、溴硫磷、辛硫磷、喹硫磷、三唑磷等农药有特异性反应．该检测技术可用于上述农药的快速定性或定量检测．     

单克隆抗体在植物研究中的应用

单克隆抗体是现代生命科学研究的重要工具。随着分子生物学的发展,单克隆抗体在植物研究中发挥着越来越重要的作用。本文综述了单克隆抗体在蛋白表达、蛋白定位、蛋白相互作用、植物成分的定性与定量、植物成分纯化、植物病害检测、标签抗体等方面研究中的应用。     

群特异性蓝舌病病毒单克隆抗体的制备和鉴定

目的：制备群特异性抗蓝舌病病毒（BTV）单克隆抗体,并对其特性进行鉴定,为建立检测BTV抗原及抗体的ELISA方法奠定基础。方法：用纯化的BTV颗粒为免疫抗原免疫BALB/c鼠,以大肠杆菌表达的VP7蛋白作为筛选抗原,用间接ELISA法筛选杂交瘤细胞株;选取抗体效价最高的一株制备BTV单克隆抗体,以该抗体为捕获抗体与8种不同血清型BTV进行ELISA反应,结果与细胞病变反应进行比对;以该抗体为竞争抗体,与12种不同血清型绵羊BTV抗血清进行竞争ELISA反应,并将结果与参比c-ELISA试剂盒结果进行比对。结果：筛选出5株稳定分泌BTV单克隆抗体的杂交瘤细胞株,并选其中一株（3E2）制备了高纯度的单克隆抗体;该单抗用于检测不同血清型BTV,与细胞病变反应结果完全相符;用于检测不同血清型绵羊BTV抗血清,其结果与参比c-ELISA试剂盒符合率为100%,与鹿流行性出血热病毒抗原和抗体均无交叉反应。结论：制备的BTV单克隆抗体具有良好的群特异性,可用于检测不同血清型BTV抗原及BTV抗体。     

单克隆抗体及其在节肢动物捕食作用研究中的应用

血清学方法是目前研究节肢动物捕食作用的较为理想的方法,特别是酶联免疫吸附试验(ＥＬＩＳＡ),由于其灵敏度高,特异性强,适于大规模检测田间样本,已被国外许多研究者采用[5]。但是所有这一切都依赖于高效价和高度特异性的抗血清,而传统的抗体制备方法常常不能满足这一要求。特别是早期使用的抗体,特异性甚至只在科的水平,不能满足准确确定猎物种类的要求[3]。而单克隆抗体不仅具有高度的特异性,而且其特异性水平可以根据需要在制备过程中进行筛选。近年来单克隆抗体在国外已开始应用于节肢动物捕食作用的研究,但在国内还未见报道。为此,我…     

抗人铁蛋白单克隆抗体的制备及其在肝癌病人血清铁蛋白测定中的应用

铁蛋白是一种肿瘤相关蛋白质。我们从人肝癌组织中分离纯化了铁蛋白,并筛选到一株抗该铁蛋白的单克隆抗体杂交瘤细胞株（６Ｄ６）,它针对铁蛋白上的构象决定簇,并对人源铁蛋白高度专一。然后我们用此单抗建立了测定铁蛋白浓度的夹心ＥＬＩＳＡ法,并对方法的灵敏度,就确度及特异性作了研究。本法用于测定不同血清标本的结果表明：肝癌病人血清中的铁蛋白浓度明显高于正常人,这可能对临床诊断会有使用价值。     

一株新型抗46 ku-细胞角蛋白的单特异性单克隆抗体

利用杂交瘤技术制备了一株单克隆抗体 T2-2,对其生化性质的研究及其与抗细胞角蛋白多克隆抗体完全重合的定位表明,该抗体特异性识别一种分子质量为 46 ku 的角蛋白. 对 68 例正常组织和 65 例肿瘤组织的免疫组化结果显示,单克隆抗体 T2-2 具有上皮细胞特异性. 与其他多数抗细胞角蛋白抗体常与一种以上细胞角蛋白多肽表现出交叉反应不同的是,该抗体只识别 46 ku 细胞角蛋白多肽上的某一单特异性表位. 另外,单克隆抗体 T2-2 适用于多种免疫实验技术,包括 ELISA、免疫组化、细胞免疫荧光及蛋白质印迹等,而且适用于多种固定剂. 以上结果表明,单克隆抗体 T2-2 将成为细胞角蛋白功能研究和肿瘤诊断的有力工具.     

单克隆抗体及其抗感染作用的研究进展

骨髓瘤细胞和单个B细胞可融合形成杂交瘤细胞,这种细胞分离并克隆后可产生针对单一表位,且结构和功能相同的抗体,即单克隆抗体(monoclonal antibody, mAb)。单克隆抗体发展历程经历了四个阶段。其制备技术也在不断革新与发展。目前单克隆抗体技术发展日益成熟,在疾病治疗与诊断中发挥着关键的作用。单克隆抗体与天然抗体不同,具有效价高、特异性强、交叉反应少、可大量制备,靶向性高等特点。mAb可用于诊断及治疗感染性疾病、自身免疫病以及癌症等。对mAb的发展历程及mAb在抗感染性疾病中的应用进行简要阐述。     

定量检测猕猴血清中重组人源化抗狂犬病毒单克隆抗体间接ELISA法的建立

目的：建立定量检测血清中重组人源化抗狂犬病毒单克隆抗体（HuMabs）NM57的间接ELISA法,为药代动力学研究提供一种简单快速的方法。方法：采用狂犬病毒糖蛋白包被酶标板、HRP标记的IgG-Fc段为标记抗体,建立定量检测HuMabsNM57的间接ELISA法,并对其特异性、灵敏度、精密度及准确度进行检测。结果：间接ELISA法检测HuMabsNM57的灵敏度为5ng／mL,组内及组间精密度分别为2．6％-6．0％、8．5％-11．3％。结论：建立了灵敏度高、特异性强的检测HuMabs NM57的间接ELISA法,精密度及准确度均符合药代动力学要求,可用于猕猴及人血清中HuMabsNM57的检测。     

抗结核分枝杆菌RpfB结构域单克隆抗体的制备及鉴定

目的:制备抗结核分枝杆菌Rpf B结构域单克隆抗体。方法:将p PRO-EXHT-Rpf B domain原核表达载体接种于大肠杆菌DH5中,用IPTG诱导表达Rpf B结构域蛋白,以纯化的Rpf B结构域蛋白作为免疫原,皮下包埋免疫小鼠3次,每次间隔2周;分离小鼠的脾细胞,与Sp2/0细胞融合,克隆化制备抗Rpf B结构域单抗,ELISA检测其效价,鉴定其特异性和相对亲和力,观察制备的抗Rpf B结构域单抗对Rpf家族其他蛋白的识别能力及其对结核分枝杆菌和藤黄微球菌的生长抑制作用。结果:制备了3株抗Rpf B结构域单抗,特异性高,亲和力较强,均能特异性识别Rpf B结构域。经小鼠腹腔注射制备腹水并纯化,获得了较高纯度的单抗,所制备的抗Rpf B结构域多肽的单克隆抗体可以识别多种Rpf样蛋白及其结构域蛋白。在抗体滴度为1∶1000时可有效抑制Rpf B结构域对结核分枝杆菌H37Ra和藤黄微球菌的生长促进作用,提示抗Rpf B结构域单抗可能会抑制进入机体内生长停滞或潜伏感染的结核分枝杆菌的再次激活,可能具有预防隐性感染复发的作用。结论:抗Rpf B结构域单抗的制备为进一步研究Rpf B结构域的生物学和免疫特性提供了实验工具。     

Eliminating murine norovirus,Helicobacter hepaticus,and intestinal protozoa by embryo transfer for an entire mouse barrier facility

Pathogens can affect physiological and immunological reactions in immunocompromised animals and genetically engineered mice. Specifically, murine norovirus (MNV), Helicobacter, and intestinal protozoa are prevalent in rodent laboratory facilities worldwide. In this study, microbiological test results of the soiled bedding of sentinel mice showed the prevalence of MNV (50.9%, 28/55), Helicobacter hepaticus (29.1%, 16/55), Trichomonas spp. (14.5%, 8/55), and Entamoeba spp. (32.7%, 18/55). No single infections were detected as all cases were confirmed to have complex infections with two or four pathogens. In previous studies, the success rate of the cross-fostering method was not perfect; therefore, in this study, the entire mouse strain of the SPF rodent facility was rederived using embryo transfer. For up to three years, we confirmed that the results were negative with regular health surveillance tests. Embryo transfer was, thus, determined to be an effective method for the rederivation of specific pathogen free (SPF) barrier mouse facilities. This is the report for the effectiveness of embryo transfer as an example of successful microbiological clean-up of a mouse colony with multiple infections in an entire SPF mouse facility and embryo transfer may be useful for rederiving.     

抗甲肝病毒基因工程单抗分离纯化与鉴定

为克服血源免疫球蛋白制品的不足,开发了抗甲肝病毒基因工程单克隆抗体anti-HAV IgG。用无血清培养基培养rCHO工程细胞株,上清液经过rProtein A SFF亲和层析→脱盐→离子交换层析→超滤换液纯化后,所得anti-HAV IgG纯度达99%以上,比活性约100IU/mg,anti-HAV IgG活性回收率40%。所纯化的anti-HAV IgG分子量150kD,等电点8.4～9.3。免疫印迹实验证实anti-HAV IgG为人源全抗体分子。亲和层析介质rProtein A SFF确实存在亲和配基脱落问题,但通过后续纯化步骤可有效除去。在亲和层析过程中加入高盐清洗步骤,可有效降低宿主DNA残留量水平。对样品中自由巯基含量进行了测定,认为非还原电泳图谱中低分子量条带是由于抗体分子内存在自由巯基引起。用该工艺制备的anti-HAV IgG各项纯度检测指标均达到我国对基因工程产品的质量要求。     

蛋白质芯片技术应用于高通量单克隆抗体制备研究

针对在传统的单克隆抗体制备过程中进行特异性筛选时大量的人力消耗,建立了一种联合应用蛋白质芯片进行单克隆抗体制备的方法。用8种重组蛋白分别免疫BALB/c小鼠,在传统的细胞融合的基础上,将8种抗原免疫的杂交瘤阳性细胞混合后进行克隆化、蛋白质芯片筛选,阳性细胞有限稀释克隆化制备相关抗体。实验结果:混合克隆化共得到单克隆细胞175孔,经蛋白质芯片筛选出阳性孔119孔,选择针对单一抗原阳性的细胞连续2轮克隆化,8种重组蛋白各获得单克隆抗体细胞株1株。与经典的单克隆抗体制备相比,蛋白质芯片筛选与混合克隆化技术联合应用于单克隆抗体制备,1个筛选周期获得了8种重组蛋白的单克隆抗体细胞株,提高了单克隆抗体的制备效率,节省了在筛选中的抗原用量,提供了一种经济、快速、简便的方法。     

蛋白质芯片技术应用于高通量单克隆抗体制备研究

针对在传统的单克隆抗体制备过程中进行特异性筛选时大量的人力消耗,建立了一种联合应用蛋白质芯片进行单克隆抗体制备的方法。用8种重组蛋白分别免疫BALB/c小鼠,在传统的细胞融合的基础上,将8种抗原免疫的杂交瘤阳性细胞混合后进行克隆化、蛋白质芯片筛选,阳性细胞有限稀释克隆化制备相关抗体。实验结果：混合克隆化共得到单克隆细胞175孔,经蛋白质芯片筛选出阳性孔119孔,选择针对单一抗原阳性的细胞连续2轮克隆化,8种重组蛋白各获得单克隆抗体细胞株1株。与经典的单克隆抗体制备相比,蛋白质芯片筛选与混合克隆化技术联合应用于单克隆抗体制备,1个筛选周期获得了8种重组蛋白的单克隆抗体细胞株,提高了单克隆抗体的制备效率,节省了在筛选中的抗原用量,提供了一种经济、快速、简便的方法。     

Preparation and Characterization of a Monoclonal Antibody to Prunus necrotic ringspot virus

A cell line named PVRSV1D11 secreting monoclonal antibody (McAb) against the prokaryotically expressed coat protein (CP) of Prunus necrotic ringspot virus (PNRSV) was developed using hybridoma technology including animal immunization, cell fusion, cell line culture and enzyme‐linked immunosorbent assay (ELISA)‐based for screening. The specificity, titre and detection sensitivity of the McAb were determined by indirect ELISA to establish optimal conditions. The antibody reacted strongly with PNRSV and showed no cross‐reactions with the proteins of Plum pox virus, Prunus dwarf virus, Apple stem pitting virus, Apple stem grooving virus, Apple mosaic virus or Apple chlorotic leafspot virus. The ascites developed with PNRSV1D11 cell line showed high absorbance until it was diluted to over 6.6 × 10⁷ fold. The McAb belonged to IgG_2a isotype and was diluted by 1.28 × 10⁵ folds as an optimal detection concentration. The detection sensitivity of the monoclonal antibody was 11.7 ng/ml protein of PNRSV. The results indicated that the McAb against the CP of PNRSV is suitable for PNRSV detection in the plants and for monitoring the dynamics of the virus by using indirect ELISA.