鸡痘病毒ORF214原核表达蛋白单克隆抗体的制备及其初步鉴定

目的:经发表的鸡痘病毒美国致病株(FPVUS)ORF214基因序列,利用PCR方法扩增出目的片段,测序后并克隆至原核表达载体pET-28a,用表达产物制备抗FPVORF214蛋白单克隆抗体(mAb)。方法:以鸡痘病毒ORF214原核表达蛋白作为免疫原,免疫BALB/c小鼠,取免疫小鼠脾细胞与Sp2/0细胞融合,用间接ELISA方法检测筛选。结果:阳性细胞株经3代克隆纯化后,获得3株能稳定分泌抗FPVORF214蛋白mAb的杂交瘤细胞株,分别命名为2F10C9、3C3B10、2G8G7。3株杂交瘤细胞分泌的抗体均能够特异地与FPVORF214蛋白反应,细胞上清ELISA效价均在1×102以上,mAb腹水效价达1×104以上。结论:该特异性mAb的研制成功为进一步研究ORF214的生物学特性奠定基础。     

抗CP4-EPSPS单克隆抗体的制备和生物学特性的鉴定

目的制备可用于胶体金快速检测试条的抗CP4-EPSPS(5-enolpyruvlshimimate-3-phosphate synthase)单克隆抗体(mAb),并鉴定其特性。方法以重组蛋白CP4-EPSPS免疫BALB/c小鼠,采用杂交瘤技术制备抗CP4-EPSPS的mAb,以间接ELISA法和Western blot进行mAb特异性鉴定;同时采用间接ELISA法鉴定mAb的Ig亚类,检测mAb的效价及相对亲和力,并进行mAb结合表位分析。结果获得2株可分泌特异性mAb的杂交瘤细胞(Ⅲ5A3,Ⅲ13A2)。其抗体亚类均为IgG1;腹水效价分别为1∶106和1∶108;相对亲和力Ⅲ5A3在105以上,Ⅲ13A2在106以上。ELISA相加实验结果显示2株mAb识别相同或相近的抗原表位。结论成功地制备出抗CP4-EPSPS的2株mAb,为建立快速特异检测转基因植物(GMO)的实验方法提供了有力的工具。     

PON2单克隆抗体的制备与初步鉴定

目的:制备PON2(paraxonase2)单克隆抗体(mAb),并进行初步鉴定.方法:利用生物信息学方法分析人类PON2蛋白序列,选取与小鼠同源性低,而免疫原性与亲水性均较强的片段,构建重组表达质粒pGEX-4T-1-PON2和PET-32a-PON2,GST-PON2和HIS-PON2融合蛋白在大肠杆菌中进行表达, 以HIS-PON2作为免疫原制备鼠mAb,以GST-PON2作为筛选抗原.采用Western blot、间接免疫荧光鉴定mAb的特异性.结果:GST-PON2和HIS-PON2融合蛋白均在大肠杆菌中获得高效表达,经常规的细胞融合和筛选获得2株可稳定分泌抗PON2的杂交瘤细胞株,这2株抗体可以识别HepG2细胞中的靶蛋白.结论:成功制备出2株抗PON2的mAb,并通过免疫荧光技术检测了该蛋白在HepG2细胞中的分布,为进一步进行PON2蛋白的的研究提供了有效的工具.     

腺病毒5型knob蛋白的原核表达、纯化及其单克隆抗体的制备

目的:表达、纯化腺病毒5型knob蛋白,并制备其单克隆抗体(mAb)。方法:克隆并表达腺病毒的knob蛋白,其氨基端带有6-His标签。纯化后的蛋白免疫BALB/c小鼠,经融合、筛选制备特异性mAb。结果:成功表达了knob蛋白。SDS-PAGE显示所表达蛋白的相对分子质量(Mr)约为23000。获得了2株分泌针对knob的杂交瘤细胞系(8D7和6D4),其分泌的mAb的Ig亚类(型)均为IgG2b。ELISA检测,对应腹水mAb的效价分别为1:2.1×105,1:2.2×105。Western blot结果显示抗knobmAb具有良好的特异性。结论:成功地制备了knob蛋白及其mAb。     

重组牛白细胞介素4的原核表达及其单克隆抗体研制

目的:原核表达重组牛白细胞介素4(rBoIL-4)并制备针对抗rBolL-4的单克隆抗体(mAb).方法:通过PCR从重组质粒pSP73-BOIL-4中扩增BoIFN-γ基因,分别克隆入表达载体pGEX-6p-1和pET-30a(+)中,构建重组菌并对其进行诱导表达、纯化和鉴定.以纯化的融合蛋白rHis-BoIL-4为...     

人HMGB1 B box蛋白的表达、鉴定及其单克隆抗体的制备

目的:表达人HMGB1 B box蛋白,制备其单克隆抗体(mAb),为进一步研究HMGB1 B box在免疫调节和抗感染免疫中的作用奠定基础。方法:将pET28-HMGB1 B box转化DH5α摇菌表达,使用His标记的蛋白纯化柱纯化、鉴定后免疫BALB/c小鼠,取免疫小鼠的脾细胞与Sp2/0细胞进行常规融合,经间接ELISA筛选阳性克隆,获得分泌人HMGB1 B box蛋白mAb的杂交瘤细胞株,通过ELISA、Western blot等方法鉴定其特性(mAb的效价、Ig类别及特异性)。结果:成功地建立了2株稳定分泌抗人HMGB1 B box的mAb细胞株,分别命名为1D2F4E3和2D4E3A2。2株mAb的免疫球蛋白类型均为IgG,Western blot显示,2株mAb均能与HMGB1 B box发生特异性反应,其滴度为1×106,mAb1 D2F4E3和2D4E3A2的A450值分别为0.324±0.093和0.296±0.085。结论:获得了2株分泌HMGB1 B box mAb的细胞株,为HMGB1 B box蛋白的生物学功能研究奠定了基础。     

人SUMO1蛋白表达纯化及单克隆抗体的制备、鉴定

目的 表达重组人SUMO1(small ubiquitin-related modifier 1)蛋白并制备单克隆抗体.方法 构建含人SUMO1基因的重组表达质粒pET32a-HIS-SUMO1,在大肠杆菌中表达重组蛋白HIS-SUMO1;以纯化后的HIS-SUMO1蛋白为抗原免疫BALB/c小鼠,利用杂交瘤技术,通过ELISA和Western blot方法筛选稳定分泌抗体的杂交瘤细胞株,用免疫双向扩散法鉴定抗体Ig的类型及亚类;取一株筛选细胞按照常规方法制备腹水,利用Millipore抗体纯化试剂盒进行抗体纯化,Western blot方法检测抗体效价.结果 表达纯化了重组人HIS-SUMO1蛋白;3株稳定分泌特异性抗人SUMO1的单克隆抗体杂交瘤细胞株被筛选出,其免疫球蛋白类型均为IgG1类;通过腹水制备和纯化获得效价较高的鼠抗人SUMO1单克隆抗体.结论 通过表达纯化人SUMO1重组蛋白,制备出高效价鼠抗人SUMO1的单克隆抗体,该抗体可用于蛋白质SUMO化的研究.     

抗鸡γ-干扰素单克隆抗体的研制及初步鉴定

目的:制备抗鸡γ-干扰素单克隆抗体(mAb)。方法:应用淋巴细胞杂交瘤技术,以重组菌BL21(DE3)(pET-ChIFN-γ)表达产物的包涵体作为抗原免疫BALB/c鼠,以纯化的GST-ChIFN-γ作为检测抗原,制备抗鸡γ-干扰素mAb;采用ELISA、Dot-ELISA和Westernblot鉴定mAb的特异性。结果:获得2株可稳定分泌抗鸡γ-干扰素mAb的杂交瘤细胞株1G5、5E3,其Ig亚类均为IgG2a,腹水mAb1G5、5E3的ELISA效价分别为1∶1600000,1∶120000。在Dot-ELISA试验中,这2株mAb均只与表达His-ChIFN-γ及GST-ChIFN-γ的重组大肠杆菌反应,与未表达这2种IFN-γ的其他8种菌株均不发生反应。在蛋白质印迹试验中,2株mAb均能与融合蛋白GST-ChIFN-γ、His-ChIFN-γ发生反应,出现特异性条带。结果表明,mAb1G5、5E3是针对鸡γ-干扰素的特异性mAb。结论:成功地制备抗鸡γ-干扰素的mAb,它们在免疫检测、免疫细胞功能分析和免疫调节研究等方面有应用价值。     

孕激素受体A 型原核表达及单克隆抗体制备

目的:制备孕激素受体A 型单克隆抗体,为后期应用到免疫组化实验提供支持。方法:选择无缝克隆的方法将目的基因与载体连接到一起,通过诱导表达收集蛋白,经过免疫后细胞融合获得单克隆抗体。将该单克隆抗体经免疫组化验证。结果:将融合后筛选的阳性细胞制备获得的单克隆抗体7C7 经免疫组化验证,发现其在乳腺癌、子宫肌瘤组织中呈现阳性,在直肠癌组织、平滑肌组织中呈现阴性,符合目的抗体的要求结论:该方法获得的孕激素受体A 型单克隆抗体较常规方法周期短,获得的抗体在不同组织间结果符合预判,对后期研究区别PR鄄A、PR-B,临床推广具有重要意义。     

GAP-43原核表达载体的构建、表达及抗GAP-43单克隆抗体的制备

目的：原核表达神经生长相关蛋白-43(GAP-43)，并制备抗GAP-43的单克隆抗体(mAb)。方法：从含有GAP-43 cDNA的质粒中，用PCR扩增GAP-43 cDNA的全长编码序列，克隆人表达载体pGEX-4T-1中，构建GAP-43的高表达工程菌，并以IPTG诱导表达日的蛋白。通过亲和层析法纯化表达的GST-GAP-43融合蛋白，并以此为抗原制备mAb。结果：酶切鉴定证明，获得含有目的基因片段的重组质粒.表达的GST-GAP-43融合蛋白以可溶性的形式存在。ELISA检测表明，获得的抗GAP-43 mAB效价为1：10^8，其IgG的亚类为IgG2a，亚型为κ型。用Western blot检测大鼠脑匀浆蛋白，在相对分子质量(Mr)为50000处有一条特异性带。用此mAb进行荧光免疫法检测表明，在致敏豚鼠的肺切片中，有GAP-43阳性的神经纤维。结论：所获抗GAP-43mAb的特异性强、效价高，对进一步研究(GAP-43在神经系统中的作用提供了有用的试剂。     

Human Natural Killer cell expression of ULBP2 is associated with a mature functional phenotype

NKG2D is an important activating receptor expressed on NK cells. Ligands (termed NKG2DL) for this receptor include ULBP1-6, MICA and MICB in humans; they are upregulated in stressed, cancerous or infected cells where they engage NKG2D to induce NK cell cytotoxicity and cytokine production.Expression of NKG2DL on effector cells has been described in mice and more recently in human cells. We confirm that NK cell lines and IL-2 stimulated primary human NK cells also express the NKG2DL, ULBP2. However, expression of ULBP2 was not a result of transfer from a non-NK cell to an NK cell and in contrast to recent reports we saw no evidence that ULBP2 expression targeted these NK cells for fratricide or for cytotoxicity by NKG2D-expressing, non-NK effector cells.ULBP2 expression was however linked to expression of mature CD57⁺ NK cells. In particular, expression of ULBP2 was strongest on those NK cells that had evidence of recent activation and proliferation. We suggest that ULBP2 could be used to identify recently activated “mature” NK cells. Defining this phenotype would be useful for understanding the ontogeny on human NK cells.     

IL-18 enhances ULBP2 expression through the MAPK pathway in leukemia cells

Expression of UL16-binding proteins (ULBPs) has been reported in various cancers, such as leukemia and melanoma, and also in some other cancer cell lines. However, the factors that modulate the expression of ULBPs are not well defined. In this study, we investigated the effects of IL-18 on the expression of NKG2D ligands in leukemia cells. IL-18 treatment increased ULBP2 expression in leukemia cells at the mRNA and protein levels. In addition, PD98059 (an ERK1/2 MAPK inhibitor) and SP600125 (a JNK inhibitor) attenuated IL-18-induced ULBP2 expression in a dose-dependent manner. We observed that ERK1/2 and JNK MAPK phosphorylation increased upon treatment with IL-18. IL-18 elevated CD107a expression in cancer cells and increased the cytotoxic activity of NK cells; therefore, we propose that IL-18 increases the susceptibility of target cells by inducing surface expression of ULBP2. Taken together, these findings suggest that IL-18 may play a critical role in regulating ULBP2 expression via the ERK1/2 and JNK MAPK pathways in leukemia cells.     

ULBP1启动子报告质粒的构建及NS3/4A蛋白对ULBP1基因转录的作用

目的: 构建含有ULBP1基因启动子的报告质粒, 并初步研究NS3/4A对ULBP1转录的影响.方法: 将ULBP1启动子核心区序列连接在pGL3-enhance载体上构建ULBP1报告质粒pGL3-ULBP1质粒;将HCV的蛋白酶NS3/4A基因亚克隆到pcDNA3-Flag载体上(pcDNA3-Flag-NS3/4A), Western blot 检测其表达.用荧光分度计检测NS3/4A对ULBP1转录水平的影响.结果: 成功构建了含有ULBP1启动子的报告质粒pGL3-ULBP1和FLAG-NS3/4A真核表达质粒, 并检测到NS3/4A可以抑制ULBP1的转录.结论: HCV的蛋白酶NS3/4A可以抑制ULBP1的转录.     

Clinical Impact of Natural Killer Group 2D Receptor Expression and That of Its Ligand in Ovarian Carcinomas: A Retrospective Study

PurposeNatural killer (NK) cells are innate immune cells with antitumor activity. NKG2D is the most important activating receptor expressed on the NK cell surface; this receptor binds to the ligands MICA/B and ULBPs to activate NK cells. The current study aimed to evaluate the expression of NKG2D by NK cells, and to the evaluate expression of its ligands in ovarian carcinomas; it also examined the clinical relevance of NK receptor/ligand expression by analyzing the relationship between expression, clinicopathological parameters, and prognosis.Materials and MethodsFormalin-fixed paraffin-embedded archival ovarian high-grade serous carcinoma (HGSC, n=79) tissue samples were used for tissue microarray analysis. The expressions of NK cell markers (CD56 and NKG2D) and NKG2D ligands (MICA/B, ULBP1, ULBP3, and ULBP2/5/6) in carcinoma tissues were evaluated by immunohistochemical staining, and the association between these results and clinical prognostic parameters was analyzed statistically.ResultsULBP1 was highly expressed in 51 cases (64.6%), and ULBP2/5/6 was highly expressed in 56 cases (70.9%) of HGSC. High expression of ULBP1 and ULBP2/5/6 was significantly associated with lower recurrence of HGSC, whereas high expression of ULBP3 was significantly associated with higher recurrence. Multivariate Cox regression analysis revealed that high expression of ULBP1 was associated with increased overall survival and a decreased hazard ratio (0.150, p=0.044), suggesting that it is an independent predictor of better survival.ConclusionHigh expression of ULBP1 predicts a better prognosis for HGSC, suggesting that ULBP1 expression could be a novel prognostic indicator in this subset of carcinomas.     

鼠抗人CXCR3单克隆抗体的研制及生物学功能研究

目的:获得持续分泌鼠抗人CXCR3单克隆抗体(mAb)的杂交瘤细胞株;以鼠抗人CXCR3 mAb作为工具,研究人CXCR3分子的表达特性及CXCR3信号转导对L929 -huCXCR3和结肠癌细胞株的迁移及增殖的影响.方法:以高表达人CXCR3膜型分子的L929-huCXCR3细胞作为免疫原免疫BALB/c小鼠,采用B淋巴细胞杂交技术,将免疫小鼠的脾脏细胞与同种系小鼠的骨髓瘤细胞sp2/0进行融合.以L929-huCXCR3作为筛选细胞,转染空载体的L929 -mock细胞作为阴性对照细胞,采用间接免疫荧光和流式细胞术,筛选能持续分泌抗人CXCR3 mAb的杂交瘤细胞株.采用Ig亚类快速定性试纸法和间接免疫荧光法对所获得的杂交瘤细胞株和mAb进行鉴定;用间接免疫荧光法分析CXCR3分子在肿瘤细胞表面的表达;Transwell隔离小室检测mAb对L929 -huCXCR3和结肠癌细胞株Colo205、HCT116及HT29迁移的影响;MTT法分析mAb对结肠癌细胞株Colo205增殖的影响.结果:获得了1株能持续分泌鼠抗人CXCR3 mAb的杂交瘤细胞株,命名为9B5.经快速定性试纸分析显示,该mAb重链为IgG1亚类,轻链为链;间接免疫荧光和流式细胞术分析显示,mAb 9B5可识别活化T淋巴细胞和结肠癌细胞株Colo205、HCT116及HT29表面的CXCR3分子.通过阻断CXCR3信号转导,mAb 9B5可抑制L929-huCXCR3细胞和结肠癌细胞株Colo205、HCT116和HT29的定向迁移及IP-10对Colo205的促增殖作用.结论:成功获得了1株能持续分泌鼠抗人CXCR3 mAb的杂交瘤细胞株,为研究CXCR3的表达特性及深入探讨CXCR3信号转导在肿瘤生长与转移过程中的作用及机制奠定了物质基础,并且有望为治疗肿瘤转移提供新的思路和新型药物.     

c‐Cbl regulates MICA‐ but not ULBP2‐induced NKG2D down‐modulation in human NK cells

The NKG2D activating receptor on human NK cells mediates “altered self” recognition, as its ligands (NKG2DLs) are upregulated on target cells in a variety of stress conditions. Evidence collected in the past years shows that, even though expression of NKG2DLs acts as a danger signal that renders tumor cells susceptible to cytotoxicity, chronic exposure to soluble or membrane‐bound NKG2DLs can lead to down‐modulation of receptor expression and impairment of NKG2D‐mediated cell functions. Here, we evaluated whether different cell‐bound NKG2DLs, namely MICA and ULBP2, are equivalently able to induce NKG2D down‐modulation on human NK cells. We found that although both ligands reduce NKG2D surface expression, MICA promotes a stronger receptor down‐modulation than ULBP2, leading to a severe impairment of NKG2D‐dependent NK‐cell cytotoxicity. We also provide evidence that the ubiquitin pathway and c‐Cbl direct MICA‐induced but not ULBP2‐induced NKG2D internalization and degradation, thus identifying a molecular mechanism to explain the differential effects of MICA and ULBP2 on NKG2D expression. A better understanding of the molecular mechanisms employed by the different NKG2DLs to control NKG2D surface expression could be useful for the development of anti‐tumor strategies to restore a normal level of NKG2D receptors on human NK cells.     

Expression and function of NKG2D in CD4+ T cells specific for human cytomegalovirus

The human NKG2D killer lectin-like receptor (KLR) is coupled by the DAP10 adapter to phosphoinositide 3-kinase (PI3 K) and specifically interacts with different stress-inducible molecules (i.e. MICA, MICB, ULBP) displayed by some tumour and virus-infected cells. This KLR is commonly expressed by human NK cells as well as TCRgammadelta(+) and TCRalphabeta(+)CD8(+) T lymphocytes, but it has been also detected in CD4(+) T cells from rheumatoid arthritis and cancer patients. In the present study, we analysed NKG2D expression in human cytomegalovirus (HCMV)-specific CD4(+) T lymphocytes. In vitro stimulation of peripheral blood mononuclear cells (PBMC) from healthy seropositive individuals with HCMV promoted variable expansion of CD4(+)NKG2D(+) T lymphocytes that coexpressed perforin. NKG2D was detected in CD28(-) and CD28(dull )subsets and was not systematically associated with the expression of other NK cell receptors (i.e. KIR, CD94/NKG2 and ILT2). Engagement of NKG2D with specific mAb synergized with TCR-dependent activation of CD4(+) T cells, triggering proliferation and cytokine production (i.e. IFN-gamma and TNF-alpha). Altogether, the data support the notion that NKG2D functions as a prototypic costimulatory receptor in a subset of HCMV-specific CD4(+) T lymphocytes and thus may have a role in the response against infected HLA class II(+) cells displaying NKG2D ligands.     

耐药性颞叶癫痫脑组织中UL16结合蛋白2(ULBP2蛋白)的表达及临床意义

目的：研究耐药性颞叶癫痫患者脑组织中ULBP2的表达,探讨其在耐药性颞叶癫痫发病中的意义。方法：从重庆医科大学附属第一医院神经内科建立的耐药性癫痫患者脑组织库中随机抽取42例耐药性颞叶癫痫患者术后脑组织,用基因芯片检测ULBP2 cDNA的表达,用免疫荧光、免疫印记法（Western blot）检测ULBP2的蛋白表达产物,并与12例对照组进行比较。结果：耐药性颞叶癫痫患者颞叶脑组织中编码ULBP2的基因出现高表达；ULBP2蛋白在耐药性颞叶癫痫患者颞叶脑组织中的表达量与对照组相同部位比较明显增高。结论：耐药性颞叶癫痫患者颞叶脑组织中ULBP2基因及蛋白产物表达增高可能与耐药性颞叶癫痫发病中的免疫异常机制有重要关联,甚至可能是关键因素。它很可能为耐药性颞叶癫痫的免疫治疗提供新的靶点。