人白介素24单克隆抗体的制备与鉴定

目的：制备抗白细胞介素24（Interleukin 24,IL-24）的单克隆抗体并对其生物学特性进行鉴定。方法：应用分子生物学技术,构建含人IL-24编码序列的原核表达载体,表达并纯化了人IL-24融合蛋白。用纯化人IL-24融合蛋白免疫Balb/c小鼠,取其脾细胞与小鼠骨髓瘤细胞SP2/0进行融合,用间接ELISA方法筛选杂交瘤细胞,有限稀释法进行亚克隆,采用免疫印迹及免疫组化染色对抗体的特异性进行了鉴定。结果：获得3株能稳定分泌抗IL-24单抗的杂交瘤细胞,分别命名为1G2,3F4,4A6。通过免疫印迹及免疫组化染色检测显示,这3株单抗均能够与IL-24特异性结合。结论：成功制备抗IL-24单克隆抗体,为进一步探索IL-24在抗肿瘤中的作用机制奠定了基础。     

抗p16单克隆抗体的制备及鉴定

目的：制备抗Ｐ１６单克隆工进行鉴定。方法：以Ｐ１６合成肽为抗原免疫纯系小鼠。利用杂交瘤技术制备单克隆抗体,并利用亲和层析等法纯化抗体。通过酶免疫测定及免疫印迹等法对单克隆抗体进行分析及鉴定,并通过免疫组化方法与进我克隆抗体进行比较。结果：获得４株稳定分泌抗Ｐ１６单克隆抗体杂交瘤株,与进口多克隆坑体比较,检测阳性及阴性符合率达１００％,但使用单克隆抗体时,组织切片不需进行抗原修复,染色效果稳定。结论     

抗人微管不稳定蛋白单克隆抗体的制备及鉴定

目的制备人微管不稳定蛋白（Stathmin）的单克隆抗体,检测Stathmin蛋白在真核细胞中的表达,为探讨Stathmin 生物学功能奠定基础。方法利用重组Stathmin蛋白为免疫原,免疫BALB/C小鼠,取免疫小鼠的脾细胞和同系小鼠的骨髓瘤细胞Sp2/0进行常规融合,通过间接ELISA的筛选和有限稀释克隆化,获得稳定分泌抗Stathmin单克隆抗体的杂交瘤细胞株,通过ELISA,Western blot和免疫组织化学实验等方法分别对其效价和特异性进行鉴定。结果成功地建立了2株稳定分泌抗Stathmin的单克隆抗体杂交瘤细胞株,分别命名为F001和F002。两株单克隆抗体的免疫球蛋白亚类均为IgG1。两株单克隆抗体通过免疫组织化学实验和Western blot实验都能特异性地结合真核细胞内源性的Stathmin蛋白。结论成功建立了两株效价高、特异性好的抗Stathmin蛋白的单克隆抗体,为进一步研究Stathmin的生物学功能及其与肿瘤的关系创造了条件。     

肝脏型脂肪酸结合蛋白的重组表达及其单克隆抗体的制备和鉴定

目的： 制备抗肝脏型脂肪酸结合蛋白(LFABP)的单克隆抗体(mAb)并进行亚型和特异性鉴定。方法：以重组的LFABP蛋白为免疫原,经过原核表达和纯化后,免疫BALB/c小鼠,获得分泌鼠抗人LFABP蛋白mAb的杂交瘤细胞株,通过ELISA 和Western blot方法检测其特异性。结果：纯化的LFABP重组蛋白免疫小鼠后经过筛选得到2株稳定分泌抗人LFABP的mAb杂交瘤细胞株,分别命名为3E6和5B7,其亚型分别为IgG1和IgG2a,抗体经纯化后浓度达到2 mg/mL,效价达到1∶10 000以上。Western blot分析结果表明可与细胞中表达的内源LFABP发生特异性免疫反应。结论：成功制备了鼠抗人LFABP的mAb,为进一步研究LFABP的生物学特性,并为相关疾病的治疗奠定了基础。     

大肠癌相关新基因ST13单克隆抗体的制备及生物学特性鉴定

目的 研制抗ST13蛋白单克隆抗体,建立检测方法,探讨ST13基因的生物学特性。方法 按淋巴细胞杂交瘤技术制备抗ST13蛋白单克隆抗体,并以亲和层析法纯化单抗,将此单抗作探针用Western-Blot和免疫组化检测标本。结果 获得3个抗ST13蛋白单抗的杂交瘤细胞株,杂交瘤细胞培养上清和腹水中单抗的ELISA效价为10^4-10^5。以ST13单抗作Wester-Blot和免疫组化证实该单抗具有高度特异性,可用于检测组织表达的ST13蛋白。结论 制备了具有高度特异性和高效价的抗ST13蛋白单抗;建立了Western-Blot及免疫组化检测组织表达的ST13蛋白的方法。     

分泌抗人甲胎蛋白单克隆抗体杂交瘤细胞株的建立

应用免疫亲和层析法纯化的正常胎儿组织中的甲胎蛋白(AFP)为抗原免疫BALB/c小鼠,取其脾细胞与小鼠骨髓瘤细胞SP2/0采取淋巴细胞杂交瘤技术进行融合,经有限稀释法进行四代克隆化后。获得十株稳定分泌抗人AFP单克隆抗体杂交瘤细胞株。其细胞培养上清中AFP单抗滴度为1:160～640,诱生同系小鼠腹水中单抗滴度为1:4000～100,000。特异性中和抑制试验显示单抗是针对AFP的。放射免疫分析示某些单抗具有较强的亲和力。杂交瘤细胞染色体数目为100～110,其分泌的抗体分别属于IgG_(2a)、IgG_1和IgM型。     

抗上皮细胞黏附分子单克隆抗体的制备及应用

 目的　制备抗人类上皮细胞黏附分子（EpCAM）的单克隆抗体（mAb）并对其进行鉴定及初步功能研究。方法　将原核表达的EpCAM免疫BALB／c小鼠,按常规方法将小鼠脾细胞与小鼠骨髓瘤Sp2／0细胞进行融合,用酶联免疫吸附试验进行阳性克隆的筛选。免疫印迹法对制备的mAb进行鉴定,用免疫组织化学法对临床的3份大肠癌组织样本进行初步检测。结果　酶联免疫吸附试验筛选获得了3株分泌抗EpCAM的mAb杂交瘤细胞株1B10、3G2和4E11。免疫印迹检测结果表明,3株杂交瘤细胞株分泌的抗体均能与EpCAM呈阳性反应,与GST蛋白不发生反应。免疫酶组织化学染色结果显示3株mAb能使3份大肠肿瘤组织样本呈现阳性反应,效果优于对照mAb。结论　成功地制备了3株识别大肠癌细胞表面抗原的mAb,这些mAb在大肠癌的诊断中可能具有一定潜在的应用价值。     

EGFRvⅢ单克隆抗体研制与鉴定

目的:制备针对EGFRvⅢ的单克隆抗体,以期待其对消化道肿瘤的靶向治疗.方法:通过人工合成EGFRvⅢ与KLH连接,免疫Balb/c小鼠,采用杂交瘤技术制备鼠源性单克隆抗体细胞株,经腹水生产抗体,并对抗体进行纯化和相关性质鉴定.结果:合成EGFRvⅢ的基因缺失融合区的相应14肽,短肽与蛋白载体KLH连接作为抗原,免疫Balb/c小鼠.制备针对表达EGFRvⅢ肿瘤而对正常组织无破坏作用的的单克隆抗体.通过常规免疫程序获得高效价(1∶128 000)抗血清的免疫小鼠后,进行细胞融合,制备杂交瘤单克隆抗体细胞.应用ELISA检测的方法筛选鉴定能分泌EGFRvⅢ抗体的杂交瘤细胞株,经亚克隆获得5株鼠源性成系抗体阳性细胞株.阳性细胞株经扩大培养,注射于小鼠腹腔以大量制备抗体.抗体型别鉴定为IgG2a,并对抗体效价及其相对亲合力进行测定.腹水效价达1∶128 000,亲和力最高达9.8×10-9 mol/L.用表达的正常EGFR配体结合区蛋白检测自制抗体的特异性,结果显示抗体不与正常EGFR配体结合区蛋白结合.结论:成功制备了抗鼠EGFRvⅢ单克隆抗体,为后续抗肿瘤的靶向治疗奠定基础.     

抗CD47单克隆抗体制备及其促巨噬细胞吞噬作用鉴定

目的:制备可识别肿瘤细胞表达CD47蛋白的抗CD47单克隆抗体,并鉴定其抗肿瘤作用。方法:利用BL21(DE3)原核表达系统表达CD47胞外段蛋白,利用Ni-NTA层析纯化表达蛋白。免疫BALB/c小鼠,制备并筛选分泌抗CD47单克隆抗体的杂交瘤细胞株。利用正辛酸-硫酸铵沉淀方法纯化抗CD47单抗。利用流式细胞术检测纯化抗体的活性。利用巨噬细胞与肿瘤细胞共培养试验,检测抗CD47单抗的抗肿瘤作用。结果:表达并纯化了CD47胞外段蛋白,筛选到了分泌抗CD47单克隆抗体的杂交瘤细胞株—7D4,流式细胞术检测结果显示,抗体具有结合肿瘤细胞的活性,但是对不同肿瘤类型细胞的结合效率存在差异。巨噬细胞与肿瘤细胞共培养试验发现,利用抗体封闭肿瘤细胞CD47信号后,可以增强巨噬细胞对肿瘤细胞的吞噬作用。结论:抗CD47单抗—7D4可以促进巨噬细胞的吞噬作用,具有潜在应用价值。     

基因免疫制备人PAK4单克隆抗体及其部分特性的鉴定

背景与目的:制备人PAK4单克隆抗体可以用于临床诊断恶性肿瘤,同时为深入探讨PAK4蛋白的功能提供可靠途径.材料与方法:用重组PAK4质粒(以P3XFLAG-CMV-10表达质粒为载体)免疫6～8周龄雌性Balb/C小鼠,通过细胞融合与克隆,筛选PAK4特异性单抗.结果:得到稳定分泌PAK4抗体的单克隆杂交瘤细胞2株,分别命名为2D1和3H4;间接ELISA方法测得2株PAK4单抗腹水效价为1∶1.0×104;单抗亚类鉴定表明2D1是IgG类,3H4是IgM类;免疫组化试验显示2株单抗均与临床两例乳腺癌组织管状上皮细胞高度反应.结论:PAK4单克隆抗体特异性较好,可用于临床肿瘤组织诊断.     

chTNT-3/hu IL-12 fusion protein for the immunotherapy of experimental solid tumors

Fusion proteins are emerging as a promising approach for targeting cytokines to the tumor site in order to generate an effective anti-tumor response. In this study, a fusion protein, chTNT-3/huIL-12, consisting of the necrosis targeting antibody, chTNT-3, and human interleukin-12 (IL-12), was constructed and expressed using the glutamine synthetase gene amplification system in NS0 cells. For these studies, IL-12 was chosen since it has been shown to be a powerful anti-tumor cytokine. To generate the fusion protein, an expression vector was prepared by linking the huIL-12 p35 subunit cDNA to the 3' end of the chTNT-3 heavy chain cDNA and the p40 subunit was added to a separate vector. The activity of the expressed chTNT-3/huIL-12 was confirmed by standard IL-12 bioactivity assays which demonstrated that the fusion protein induced similar levels of peripheral blood lymphocyte (PBL) proliferation as free recombinant IL-12. In addition, the lytic activity of the fusion protein was demonstrated in both naive and IL-2-activated lymphocytes using cytotoxicity assays against three human pancreatic and prostatic cancer cell lines (CAPAN, DU145, and PC3-MA). Human PBL incubated with this fusion protein showed an increase in IFN-gamma production which was augmented dramatically by pre-incubation with IL-2. Finally, the immunotherapeutic potential of the fusion protein was demonstrated in the human PBL-SCID mouse model where a 44% reduction in DU145 prostatic tumor growth was obtained compared to control treated mice. These results demonstrate that tumor-targeted human IL-12 may be an effective immunotherapeutic reagent for the treatment of solid tumors in man.     

过表达MDA-7/IL-24蛋白的亚细胞定位

目的了解标签蛋白GFP的位置对过表达的MDA-7/IL-24融合蛋白亚细胞定位的影响。方法分别构建在MDA-7/IL-24 cDNA的5'端和3'端带有GFP-tag的重组表达质粒pEGFP-C1-mda-7/IL-24和pEGFP-N3-mda-7/IL-24,瞬时转染猴胚肾Cos7细胞,48h后用Hoechst 33258染核,在荧光显微镜下观察GFP-MDA-7/IL-24融合蛋白在Cos7细胞的亚细胞分布。结果测序表明重组质粒pEGFP-C1-mda-7/IL-24和pEGFP-N3-mda-7/IL-24构建正确;分别转染Cos7细胞后,在氨基端带有GFP-tag的MDA-7/IL-24融合蛋白表达阳性细胞中,绿色荧光均匀分布于胞浆和胞核,但在羧基端带有GFP-tag的MDA-7/IL-24融合蛋白表达阳性细胞中,绿色荧光则分布于核膜外侧和胞浆。结论GFP-tag位置的不同对过表达融合蛋白MDA-7/IL-24的亚细胞定位有显著的影响。     

腺病毒介导mda-7/IL-24基因感染对卵巢癌耐药细胞凋亡的影响

背景与目的:Mda-7/IL-24基因是一个具有选择性的诱导肿瘤细胞凋亡和细胞因子免疫调节功能双重作用的基因,在抗肿瘤基因治疗方面有很好的应用前景,本研究利用构建的mda-7/IL-24重组腺病毒感染卵巢癌耐药细胞株,了解其对卵巢癌耐药细胞的抗肿瘤作用.方法:利用腺病毒AdEasy 1载体构建含目的基因的Ad.mda-7/IL-24,感染两种卵巢癌耐药细胞株OVCAR-3和OVCAR-8/TR,Western blot法检测感染后MDA-7/IL-24蛋白表达,用Hoechst33258凋亡染色和流式细胞仪检测感染后细胞的凋亡和细胞周期改变.结果:Ad.mda-7/IL-24经测序、酶切电泳、感染后Western blot检测MDA-7蛋白表达,表明构建成功;感染Ad.mda-7后72 h内OVCAR-3细胞最高凋亡率为14.1%,OVCAR-8/TR细胞为32.4%,明显高于空载体组和未感染组.结论:成功构建了Ad.mda-7/IL-24重组腺病毒,用其感染卵巢癌耐药细胞可诱导细胞凋亡.     

Interleukin-6 fused to an anti-idiotype antibody in a vaccine increases the specific humoral immune response against CA125+ (MUC-16) ovarian cancer

Anti-idiotypic (Id) monoclonal antibodies can serve as surrogate for tumor-associated antigens in vaccination strategies. The murine anti-Id monoclonal antibody ACA125 that mimics the CA125 carbohydrate antigen expressed on ovarian cancer cells induces an anti-anti-Id antibody (Ab3) response that is associated with prolonged survival of ovarian cancer patients. To increase the Ab3 antibody response, we evaluated two strategies in a mouse model: (a) coinjection of human interleukin (IL)-6 together with the fusion protein chACA125, which consists of the anti-Id ACA125 single-chain Fv antibody joined to the human IgG1 CH2/CH3 domain; and (b) injection of the fusion protein chACA125-IL-6, which consists of the ACA125 single-chain Fv fused to human IL-6 via the IgG1 CH2/CH3 domain. Vaccination of mice with the chACA125-IL-6 fusion protein resulted in higher titers of anti-CA125 (Ab3) antibodies compared with application of the chACA125 antibody with or without systemic coadministration of IL-6. Application of the chACA125-IL-6 fusion protein did not elicit detectable antihuman IL-6 antibody titers, whereas coinjection of human IL-6 did. Taken together, these data suggest that the chACA125-IL-6 fusion protein directly stimulates ACA125-specific B cells via the IL-6 domain, whereas coinjection of IL-6 leads to an overall immune stimulation. Antigen-IL-6 fusion proteins will improve vaccination regimens and anticancer immunotherapeutic strategies by increasing the antigen-specific humoral immune response.     

Anti-CD30-scFv-Fc-IL-2 antibody-cytokine fusion protein that induces resting NK cells to highly efficient cytolysis of Hodgkin's lymphoma derived tumour cells

The pathogenesis of Hodgkin's disease (HD) is associated with the accumulation of functionally anergic T cells in the near vicinity of the malignant Hodgkin/Reed-Sternberg (H/RS) cell. To stimulate locally the anti-tumour immunity in Hodgkin's disease, we generated an anti-CD30-antibody-interleukin-2 fusion protein (HRS3-scFv-Fc-IL-2) that binds to CD30 constitutively expressed on H/RS cells. The fusion protein is composed of a CD30 binding domain (HRS3-scFv) that is linked via the human IgG hinge-CH2/CH3 domain to human IL-2. The HRS3-scFv-Fc-IL-2 fusion protein is expressed as a 140 kDa homodimer, has binding specificities to both the CD30 antigen and the IL-2 receptor and stimulates proliferation of preactivated T cells in vitro, demonstrating its IL-2 bioactivity. After binding to CD30+ Hodgkin lymphoma cells, HRS3-scFv-Fc-IL-2 moreover induces resting NK cells, but not T cells, to lyse the lymphoma cells with high efficiency. Recruitment of resting NK cells towards a cytolytic immune response against CD30+ lymphoma cells has the potential to build up an effective anti-tumour response despite of Hodgkin's disease associated T-cell anergy and makes the HRS3-scFv-Fc-IL-2 fusion protein suitable for the specific immunotherapy of Hodgkin's lymphoma.     

Mechanistic aspects of mda-7/IL-24 cancer cell selectivity analysed via a bacterial fusion protein

The human mda-7/IL-24 gene product is normally expressed in melanocytes and certain lymphocyte populations. Loss of expression, a distinctive feature of many tumor suppressor genes, has been documented at RNA and protein levels in association with melanoma progression both in vitro as well as in human tumor-derived material. The MDA-7/IL-24 protein undergoes post-translational processing, including removal of an amino-terminal 48-residue signal peptide and extensive glycosylation prior to its secretion by producing cells. Its inherent cytokine properties have been documented in multiple reports, which have identified and characterized its cognate receptors and activation of the JAK/STAT signaling pathway following ligand/receptor docking. A notable and incompletely understood property of MDA-7/IL-24 is its ability to induce apoptosis in transformed cells, while having marginal growth suppressive effects on normal primary or immortalized cell lines. MDA-7/IL-24 has been delivered to cells, tumor xenografts and patients in clinical trials via a nonreplicating adenovirus (Ad.mda-7). Studies utilizing eukaryotically expressed and purified MDA-7/IL-24 protein from several sources have recapitulated some of the molecule's reported properties including receptor binding and JAK/STAT activation. Here, we report the properties and characteristics of a bacterially expressed and purified GST-MDA-7 fusion protein. These studies reveal that GST-MDA-7 retains its cancer-selective apoptosis-inducing properties, thereby providing a new reagent that will assist in defining the mechanism of action of this novel cytokine. In addition, retention of tumor-specific activity of GST-MDA-7 suggests that this protein may also have therapeutic applications.     

树突细胞-食管癌融合细胞体外诱导特异性抗食管癌免疫反应

背景与目的:树突细胞(dendritic cells,DC)是人体专职的抗原呈递细胞,以DC为基础的DC/肿瘤细胞融合疫苗可以有效地诱导特异性抗肿瘤免疫应答.本研究旨在探讨成熟的DC与人食管癌细胞株ECl09细胞融合疫苗体外诱导特异性抗食管癌细胞的免疫反应.方法:从健康志愿者外周血中分离出单个核细胞(peripheral blood mononuclear cells,PBMC),在重组人粒/巨噬细胞集落刺激因子(recombinant human granulocyte-macrophage-colony-stimulating factor,rhGM-CSF)和白介素(interleukin-4,IL-4)作用下体外诱导DC,采用聚乙二醇(polyethylene glyco1,PEG)融合法使DC与EC109细胞融合制备DC/EC109细胞融合疫苗,四甲基偶氮唑盐(MTT)实验检测融合疫苗刺激T淋巴细胞增殖的活性,乳酸脱氢酶(LDH)实验检测融合疫苗活化的细胞毒性T淋巴细胞(cytotoxic T lymphocyte,CTL)在体外特异性杀伤EC109细胞的活性,并与对人胃癌细胞株SGC7901及人乳腺癌细胞株MCF7的杀伤作用进行比较.结果:DC与EC109细胞的融合效率最高达到22.25%.DC/EC109细胞融合疫苗能有效地刺激T淋巴细胞的增殖反应,其刺激T淋巴细胞增殖的能力显著高于DC或EC109细胞(P＜0.05).DC/EC109细胞融合疫苗活化的CTL对EC109细胞具有特异性的杀伤作用,对EC109细胞的杀伤作用显著强于对SGC7901细胞及MCF7细胞的杀伤作用(P＜0.05).结论:DC/EC109细胞融合疫苗能有效诱导抗EC109细胞的特异性免疫应答.