免疫亲和层析纯化大肠癌相关抗原

目的 :从培养的大肠癌细胞Hce 86 93中分离纯化并鉴定大肠癌相关抗原。方法 :利用流式细胞术选择高表达大肠癌相关抗原的大肠癌细胞系 ,分别用单去污及三去污裂解液裂解细胞。然后用 5株抗大肠癌单克隆抗体 (mAb)CYL 1～CYL 5进行Westernblot,分析与大肠癌细胞结合反应最强的mAb。以此mAb作为配基进行亲和层析纯化大肠癌相关抗原 ,纯化结果利用Westernblot法进行鉴定。结果 :大肠癌细胞系Hce 86 93上相关抗原的表达量最高 ;抗大肠癌mAbCYL 2与Hce 86 93的结合力最强。纯化所获与CYL 2特异结合的大肠癌相关抗原 ,Mr 约为 13× 10 3 。该抗原由Mr 为 6 0× 10 3 和70× 10 3 两种亚基组成。结论 :利用mAbCYL 2进行亲和层析 ,从大肠癌细胞系Hce 86 93中获得纯化的肿瘤相关抗原。     

检测肌糖蛋白C夹心ELISA方法的建立及初步应用

目的:以已经制备的抗肌糖蛋白C(TN-C)的单克隆抗体(mAb)为基础,建立能定量检测肌糖蛋白C浓度的夹心ELISA方法,并初步于临床血清标本检测.方法:将3株mAb(克隆号分别为:1A8、3H7和4D6)制备腹水后纯化,分别与辣根过氧化物酶交联后,两两配对,以重组肌糖蛋白C 蛋白为检测抗原,分析抗体之间最佳组合;利用建立的夹心ELISA方法检测收集的临床骨肉瘤患者和正常人血清标本.结果:包被1A8 mAb,HRP-4D6配对敏感性最高;骨肉瘤患者血清中肌糖蛋白C浓度明显高于正常人.结论:成功建立检测肌糖蛋白C的夹心ELISA方法,并利用其检测到肌糖蛋白C在骨肉瘤患者中的浓度异于正常人.     

抗人结肠癌相关抗原单克隆抗体的制备及初步研究

目的：制备抗人结肠癌相关抗原的单克隆抗体4D10，运用组织芯片技术研究其与人结肠癌组织反应的情况。方汪：用人结肠癌细胞株LOVO免疫小鼠，用间接细胞ELISA和免疫组化的方法筛选抗结肠癌相关抗原的单抗。结果：获得一株能够稳定分泌抗人结肠癌相关抗原的杂交瘤细胞株。4D10能够与不同分期的结肠癌组织切片反应，且与正常组织和其他癌组织几乎不反应。结论：4D10对结肠癌的病理分期及预后结果都具有一定的临床参考价值。     

抗重组GST单克隆抗体的制备及其在融合蛋白纯化中的应用

目的 制备抗重组GST的单克隆抗体（mAb),并用来纯化重组GST融合蛋白,方法 用含重组GST融合蛋白基因的pGEX4T-1质粒转化E.coliBL21,IPTG诱导GST融合蛋白表达,亲和层析和凝胶过滤法分离表达的重组GST融合蛋白,以此蛋白作为抗原,免疫Balb/c小鼠,按传统的杂交瘤技术制备mAb。将抗GSTmAb经ProteinA纯化后,与Sepharose4B偶联。结果 经3次亚克隆后,获得两株分泌抗GST载体特异性mAb的杂交瘤,采用该mAb对两种不同的GST融合蛋白进行亲和层析纯化后,经SDS-PAGE鉴定达到了商品化Glutathione-Resin的亲和层析纯化效果。结论 用抗GST蛋白特异性mAb亲和层析纯化融合蛋白是一种经济、实用的方法,且可用于Glutathione-Resin亲和层析纯化后的二次纯化。     

人睾丸特异性新基因hT279单克隆抗体制备及其应用

目的构建人睾丸特异性新基因hT279(GenBank登录号BC016750)的原核表达载体,纯化融合蛋白并以其为抗原免疫Balb/c小鼠制备抗人睾丸特异性hT279蛋白单克隆抗体(mAb)并进行特性鉴定。方法用PCR方法得到睾丸特异性新基因hT279并克隆至pET32a原核表达载体中,转化大肠杆菌BL21诱导融合蛋白表达;获得的可溶性蛋白经亲和层析纯化、SDS-PAGE鉴定后,免疫Balb/c小鼠,应用淋巴细胞杂交瘤技术制备抗hT279 mAb,并通过间接ELISA、Western blot和免疫组织化学法对mAb进行特性鉴定。结果实现了hT279的原核表达,获得了1株稳定分泌抗hT279 mAb的杂交瘤细胞株4B2,抗体亚型为IgG2b(κ),效价达到1×104。Western blot鉴定表明,该mAb在人正常睾丸蛋白中相对分子质量约为22 000处检测到特异条带。免疫组织化学显示hT279蛋白主要在正常人睾丸的精母细胞及圆形精子细胞中表达,而在男性不育患者睾丸组织中表达消失。结论成功制备出1株抗hT279的mAb 4B2,为进一步研究hT279在人类精子发生中的功能和男性不育症的诊断提供了特异的检测工具。     

重组人颗粒溶素的纯化及其单克隆抗体的制备

目的:纯化原核系统表达的颗粒溶素(GNLY),并制备其单克隆抗体(mAb)。方法:用Ni亲和层析纯化重组人GNLY,用其免疫BALB/c小鼠,采用常规杂交瘤技术制备相应的mAb。mAb纯化后,用间接ELISA法测mAb的效价,ELISA相加试验测定抗原表位,硫氰酸盐洗脱法测定mAb的相对亲和力指数,并进行Ig亚类、特异性及杂交瘤细胞分泌mAb的稳定性检测。结果:经Ni亲和层析纯化的可溶性GN-LY融合蛋白,其纯度和含量分别为95%和0.8g/L。共筛选出能稳定分泌抗人GNLYmAb的杂交瘤细胞4株,分别为6C8、9C6、5G7和5E5。4株杂交瘤细胞培养上清及腹水中mAb的效价分别为1∶100～1∶3200和(0.1～8)×10-4,5E5mAb的Ig亚类为IgM,其余3株mAb均为IgG1。结论:成功地纯化人GNLY融合蛋白。以其为免疫原制备的鼠抗人GN-LYmAb,为实验室及临床研究奠定了一定的基础。     

免疫亲和层析法纯化重组人促红细胞生成素的实验研究

目的 以免疫亲和层析方法纯化重组人促红细胞生成素（rhEPO)。方法 以rhEPO作为抗原，免疫Balb/C小鼠，制备抗rhEPO单克隆抗体（mAb)。以纯化的抗rhEPOmAb2F12与预活化的Sepharose4B偶联，制成抗体亲和层析柱，纯化rhEPO。结果 经筛选共获得4株可分泌抗rhEPOmAb的杂交瘤细胞株，分别为：1A8、2F12、3D4和3F10。亲和层析纯化的rhEPO经SDS-PAGE显示单一条带，2g凝胶制备的层析柱一次层析可获得1.5mg 高纯度的rhEPO。利用纯化的mAb建立的ELISA法，用于检测rhEPO的蛋白含量可达ng水平。结论 免疫亲和层析法纯化rhEPO的效率高，纯度好，用纯化的mAb建立的ELISA法具有灵敏度高，重复性和稳定性好等优点。     

幽门螺杆菌napA基因的克隆、表达及免疫反应性分析

目的构建高效表达幽门螺杆菌(Hp)中性粒细胞激活蛋白(NAP)的原核表达系统,为Hp候选疫苗研制打下基础。方法从Hp标准株NCTC11639染色体DNA中扩增napA基因片段,T-A克隆后测序,与GenBank公布的其他Hp菌株的napA基因序列进行比较。目的基因片段酶切后,与表达载体连接,转化至宿主菌,构建napA基因原核表达系统pGEX-4T-1-napA-E.coliTop10。优化诱导表达条件,采用SDS-PAGE鉴定表达产物,GST亲和层析纯化收集重组NAP蛋白,Western blot法鉴定重组NAP的免疫性;采用ELASA法检测胃癌患者Hp阳性血清中抗NAP抗体效价,通过间接ELASA法从29株小鼠抗Hp全菌单克隆抗体(mAb)中筛选抗Hp-NAPmAb。结果所克隆的napA基因全长为435bp,在GenBank上登录(No.DQ341279),与GenBank公布的其他Hp菌株的核苷酸同源性为94%~98%,与国际测序模式株Hp26695、HpJ99同源性达97%,表达的NAP融合蛋白的相对分子质量(Mr)为44000,1mmol/L浓度IPTG诱导4h表达产物量较高,表达产物可被Hp感染患者的血清及兔抗Hp全菌抗体特异性结合,胃癌患者血清中抗NAP抗体效价高于正常人群血清,29株小鼠抗Hp全菌mAb中有3株mAb能与NAP发生强免疫反应。结论成功构建napA基因高效可溶性原核表达系统,重组NAP具有良好的免疫反应性,NAP在胃癌患者血清中高表达可能与胃癌的发病有关,NAP是具有良好前景的抗原。     

人丙氨酸氨基转移酶(ALT2)的表达、单克隆抗体制备及鉴定

目的:克隆、表达、纯化重组人丙氨酸氨基转移酶(ALT2),以此作为抗原免疫动物获得针对ALT2的单克隆抗体(mAb)株,用于ALT的免疫诊断。方法:通过RT-PCR从肝癌细胞中扩增丙氨酸氨基转移酶(ALT2)基因,并将其克隆至pET-28a表达载体中,带有组氨酸标签的ALT2蛋白经镍亲和层析纯化,纯化的ALT2作为抗原免疫小鼠制备mAb,通过Western blot和ELISA方法测定mAb的亲和力和特异性。结果:利用大肠杆菌成功表达ALT2蛋白,以镍亲和层析纯化获得ALT活性超过10 000 U/L的ALT2目的蛋白,以此蛋白免疫小鼠后得到5株mAb。结论:经过初步筛选获得2株高特异性的mAb,为研制ALT2蛋白定量检测试剂提供了重要工具。     

抗人生长转化因子15单克隆抗体制备及鉴定

目的:制备抗人生长转化因子15(GDF15)单克隆抗体(mAb)并鉴定其特性。方法:构建GDF15原核表达载体pGEX-4T-2-gdf15,诱导表达并纯化GST-GDF15融合蛋白。以该融合蛋白免疫BALB/c小鼠,取小鼠的脾细胞与同系小鼠Sp2/0骨髓瘤细胞常规融合,依次进行阳性杂交瘤细胞株的筛选及亚克隆,最终获得稳定分泌抗GDF15 mAb杂交瘤细胞株。以间接ELISA法检测抗体效价;Western blot鉴定抗体特异性;免疫共沉淀法初步检测在肝癌患者血清中GDF15表达水平。结果:获得1株稳定分泌抗人GDF15 mAb杂交瘤细胞株,命名为9G3;抗体免疫球蛋白亚类为IgG1,轻链为κ型;免疫共沉淀及质谱分析证实抗GDF15 mAb9G3能与肝癌患者血清中GDF15蛋白特异性结合并且GDF15水平在肝癌患者血清中较正常人显著升高。结论:成功制备了抗人GDF15mAb,为后期肝癌早期诊断试剂盒的开发奠定了良好的基础。     

抗rhEPO单克隆抗体的制备及初步应用

目的 :研制抗人促红细胞生成素的特异性单克隆抗体 (mAb) ,对其生物学特性进行初步鉴定 ,并用于转基因羊乳中重组人促红细胞生成素 (rhEPO)的提纯。方法 :以自制的rhEPO粗品免疫BALB/c小鼠 ,制备抗rhEPO的mAb。以Westernblot和间接ELISA法 ,对所获mAb进行初步鉴定。以纯化的mAb同预活化的Sepharose 4B偶联 ,制得mAb亲和层析柱 ,并用于转基因羊乳中rhEPO的提纯。结果 :获得两株可分泌特异性抗rhEPO的mAb的杂交瘤细胞株 (1E7和 2E6 )。Ig亚类 (型 )的鉴定分别为IgG1和IgG2b ,轻链均为κ型。用Westernblot证实 ,获得的mAb可特异性地识别rhEPO。用自制的免疫亲和层析柱用于转基因羊乳中rhEPO的提纯 ,具有很好的吸附作用 ,回收率达 70 %。结论 :成功地获得两株可分泌特异性抗rhEPO的mAb的杂交瘤细胞。用自制的免疫亲和层析柱提纯转基因羊奶中的rhEPO具有较高的吸附效率     

A novel tumor-specific human single-chain Fv selected from an active specific immunotherapy phage display library

A colon tumor-associated antigen, CTAA 28A32-32K (CTA #2E), related to the annexin family of proteins, was initially identified by its reactivity with a low affinity human IgM monoclonal antibody (mAb), 28A32. Both in vitro lymphoproliferative assays with human peripheral blood lymphocytes and delayed type hypersensitivity responses in patients immunized with autologous colon tumor cells indicated that CTA #2E elicits potent T cell mediated responses and may be an important antigen in the development of a generic colorectal vaccine (Pomato et al. Vaccine Res 1994;3:145–161). A CTA #2E-specific, murine hybridoma-derived mAb, 5-11A, which recognizes the amino-terminus of the tumor-associated antigen, exhibited qualitative human colon tumor-specific immunohistochemical reactivity. To rapidly develop a human mAb with similar antigen specificity and tumor reactivity as the murine 5-11A mAb, antibody phage display technology was employed. Two human antibody phage display libraries with 3.1×10⁷ and 2.3×10⁸ members were prepared from the variable region genes expressed by circulating B cells of patients undergoing active specific immunotherapy (ASI) with autologous tumor cells, predominantly from the colon, admixed with Bacille Calmette-Guérin (BCG). A CTA #2E-reactive human single-chain (sc)Fv was selected by panning the larger library on decreasing concentrations of biotinylated tumor-associated antigen in solution. It exhibited similar antigen specificity as the murine hybridoma-derived 5-11A scFv, requiring the presence of the CTA #2E amino-terminus for reactivity. This human scFv exhibited qualitative human colon tumor-specific immunohistochemical reactivity when displayed as a gene III fusion protein on phage. When reconstructed and expressed as an intact human IgG₁, K mAb, its qualitative colon tumor-specificity was unaltered. Two other CTA #2E-reactive human scFvs were selected from the smaller library by panning initially on decreasing concentrations of CTA #2E coated to polystyrene and then on biotinylated CTA #2E in solution. These human scFvs, which exhibited modest reactivity with different epitopes on the CTA #2E antigen, did not exhibit human colon tumor-specific immunohistochemical reactivity.     

Identification and isolation of a common tumor-associated molecule using monoclonal antibody

A monoclonal antibody, 16B-13, derived from the immunization of BALB/c mice with a lung tumor line, immunoprecipitates a common tumor-associated molecule with an apparent mol. wt of 37,000 from lactoperoxidase-ionated lung carcinoma, colon carcinoma, gastric carcinoma, brest carcinoma, melanoma and lymphona cells, but not from normal fibroblasts. Analysis by two-dimensional gel electrophoresis of the cell surface-labeled 16B-13 antigen from a colorectal and a melanoma cell line reveals four components with similar mol. wts but with different isoelectric points. The antigen purified froma a colorectal carcinoma cell line by immunoaffinity chromatography was shown to be a 37,000 mol. wt polypeptide similar to that obtained by the lactoperoxidase-labeling procedure. However, the purified antigen from the melanoma cell line shows the presence of a 65,000 mol. wt polypeptide and the loss of the 37,000 mol. wt component as detected by Comassie blue staining and immunoprecipitation.     

新的结肠癌相关抗原MC3－Ag的纯化及鉴定

作者利用饱和硫酸铵沉淀和ＤＥＡＥ５２离子层析柱纯化本中心自制结肠癌单克隆抗体ＭＣ３，以此为配基与Ｓｅｐｈａｒｏｓｅ４Ｂ偶联，经免疫亲和层析从自制可溶性结肠癌抽提液中纯化出一种新的肠癌肿瘤相关抗原ＭＣ３－Ａｇ。其特性分析表明，ＭＣ３－Ａｇ可为高碘酸氧化或强硷水解，而对胰蛋白酶、神经氨酸酶、去糖酯混合液及弱硷处理不敏感，提示其决定簇可能位于Ｎ糖苷键型糖蛋白糖链上。ＳＤＳ－ＰＡＣＥ及免疫印迹分析表明ＭＣ３－Ａｇ的分子量为２８．８ｋＤ。免疫反应分析ＭＣ３－Ａｇ不与ＣＥＡ、ＡＦＰ等已知结肠癌相关抗原的单克隆抗体反应。     

胃癌相关抗原表位模拟短肽的筛选

目的：筛选能模拟胃癌相关抗原表位的功能短肽。方法：利用离子交换层析，对抗胃癌相关抗原单克隆抗体(mAb)进行纯化，并以此mAb为靶标，将其包被于ELISA板上，以噬菌体随机12肽库对其进行3轮亲和筛选。结果：从噬菌体随机12肽库中，筛选到12个噬菌体阳性克隆：结论：获得了具有模拟胃癌相关抗原表位的阳性噬菌体克隆，且有共同的基序。     

Induction of specific immunity to human colon carcinoma by anti-idiotypic antibodies to monoclonal antibody CO17-1A

Anti-idiotypic antibodies (Ab2) to murine monoclonal antibody (mAb) CO17-1A (Ab1), which defines an antigen associated with human colon carcinoma, were produced in goats. The Ab2 inhibited binding of Ab1 to colon carcinoma cells, and purified tumor antigen inhibited binding of Ab1 to Ab2. The Ab2 elicited in rabbits anti-anti-idiotypic antibodies (Ab3) that bound to cultured human cells of various tissue origins with a binding pattern identical to that of Ab1. Moreover, both Ab1 and Ab3 bound to the isolated tumor antigen, and the Ab3 lysed human colon carcinoma cells in culture in the presence of rabbit complement. Thus, Ab2 raised to mAb CO17-1A are candidates for use in immunotherapy trials in cancer patients.     

日本血吸虫铁蛋白基因的克隆、表达及其免疫诊断的研究

目的：构建、表达、纯化日本血吸虫铁蛋白基因的原核表达重组蛋白，并初步观察其免疫诊断价值。方法：将日本血吸虫铁蛋白基因亚克隆于pGMC载体，转化重组体到大肠杆菌E．coli 2566进行表达；采用电泳层析法分离纯化日本血吸虫铁蛋白；用SDS-PAGE和Western blot鉴定表达纯化产物；用Dot-ELISA分别检测了血吸虫病人及正常人的血清。结果：重组的日本血吸虫铁蛋白以GMC(粒细胞巨噬细胞集落刺激因子)．日本血吸虫铁蛋白融合蛋白的形式在细菌中得到高效表达，分子量为40kD，能被日本血吸虫感染兔血清识别。用重组铁蛋白检测30例日本血吸虫病人血清和30例正常人血清，阳性率和假阳性率分别为93．3％和3．3％。结论：成功地表达纯化日本血吸虫重组铁蛋白．且该蛋白具有一定的免疫诊断价值．     

抗Ig融合蛋白Fc段单克隆抗体的制备、鉴定与应用研究

目的：制备并鉴定抗Ig融合蛋白Fc段的单克隆抗体(mAb)，建立用于检测Ig融合蛋白的夹心ELISA法和纯化Fc融合蛋白的亲和层析法。方法：以hBCMA—Ig融合蛋白为抗原免疫BALB／c小鼠，通过细胞融合制备抗Fc段mAb，用ELISA等方法鉴定mAb的Ig亚类、表位以及种属特异性，建立用于检测Ig融合蛋白的夹心ELISA法;Western blot检测mAb对变性Ig融合蛋白的反应性。将mAb与Sepharose4B交联，制备亲和层析柱，对LAIR1-Ig融合蛋白进行纯化。结果：获得7株稳定分泌抗Fc段mAb的杂交瘤(FMUFcl-FMUFc7)。利用FMUFc4作为包被mAb，FMUFc5作为酶标记mAb，成功地建立了检测Ig融合蛋白的ELISA法，敏感度达到2μg／L；在7株mAb中，FMUFc6可用于Ig融合蛋白的western blot检测。用FMUFc 6mAb制备的亲和层析柱，可有效地纯化LAIRl—Ig融合蛋白。结论：成功地制备了抗Ig融合蛋白Fc段的mAb，建立了可用于Ig融合蛋白检测和纯化的方法，为Ig融合蛋白的应用提供了有力手段。     

Identification and characterization of an immunodominant 58-kilodalton antigen of Aspergillus fumigatus recognized by sera of patients with invasive aspergillosis.

Sera from 38 patients with invasive aspergillosis were tested by Western immunoblotting for the presence of antibodies to antigens of Aspergillus fumigatus present in a mycelial extract of the organism. All of the sera contained antibodies to an antigen of molecular weight 58,000, which was which was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. It was the only antigen recognized in approximately 90% of the sera tested. The 58-kDa antigen is an abundant component of mycelial extracts composing approximately 50% of the Coomassie blue-stained protein. The antigen also contains carbohydrate, since it is stained by the carbohydrate stain periodic acid-Schiff and it binds to the lectin concanavalin A. It was purified by immunoaffinity chromatography employing a monoclonal antibody directed against an epitope on the 58-kDa antigen. Analysis of the purified antigen by gas-liquid chromatography revealed the presence of mannose, galactose, and glucose residues in a 2:1:2 ratio. The ratio of protein to carbohydrate is 1.16:1. The protein is slightly acidic, containing relatively high quantities of glutamic and aspartic acids, glycine, alanine, serine, and threonine. The 58-kDa antigen also contains phosphate groups as part of its structure. Serological activity was totally destroyed after treatment with sodium metaperiodate and was partially destroyed after treatment with pronase. The 58-kDa antigen was not able to hydrolyze protein.