人树突状细胞cDNA质粒文库的构建及其大规模随机测序体系的 …

目的：建立人树突状细胞的ｃＤＮＡ文库。通过大规模随机测序克隆免疫新分子,方法：来源于正常人外周血的单核细胞,体外经ＧＭ－ＣＳＦ和ＩＬ－４培养,扩增出高纯度的ＤＣ,抽提纯化ｍＲＮＡ,转录成ｃＤＮＡ,定向插入ｐＳＰＯＲＴ２．０载体,建立人ＤＣ的ｃＤＮＡ质粒文库;用ＡＢＩ３７７全自动测序仪对该文库进行随机测序,将得到的ＥＳＴ在Ｓｕｎ－Ｅ４５０服务器中与ＥＭＢＬ及Ｓｗｉｓｓｐｒｏｔ数据库进行同源性比较,筛     

丙型肝炎病毒及恶性疟原虫复合多表位抗原基因与谷胱甘肽转硫酶基因的融合表达及其在小鼠中免疫应答的研究

目的：探讨复合多表位丙型肝炎病毒（ＨｅｐａｔｉｔｉｓＣｖｉｒｕｓ,ＨＣＶ）及恶性疟原虫（Ｐｌａｓｍｏｄｉｕｍｆａｌｃｉｐａｒｕｍ,Ｐｆ）双价疫苗的可行性。方法：将人工合成的复合多表位ＨＣＶ基因ＰＣＸ及Ｐｆ抗原基因ＡＢ（ＳＰｆ６６＋ＳＰｆ１０５）克隆到谷胱甘肽转硫酶（ＧｌｕｔａｔｈｉｏｎｅＳｔｒａｎｓｆｅｒａｓｅ,ＧＳＴ）表达载体ｐＧＥＸ２Ｔ中,并在大肠杆菌中高效表达ＧＳＴＨＣＶＰｆ复合抗原（ＧＳＴＣＡＢ）,分析表达产物的免疫特异性、免疫原性及安全性。结果：ＧＳＴＣＡＢ可被ＨＣＶ患者血清、鼠抗ＧＺＰＣＸ及鼠抗Ｐｆ抗体特异识别,可诱发小鼠产生针对ＧＳＴＣＡＢ、ＧＺＰＣＸ及ＰｆＡｇ的特异性体液免疫应答及针对ＧＳＴＣＡＢ、ＧＺＰＣＸ的迟发性超敏反应,免疫后ＣＤ８＋Ｔ细胞比例略为升高,免疫小鼠未见明显的毒副作用。结论：ＧＳＴＣＡＢ融合蛋白具有良好的ＨＣＶ及Ｐｆ免疫特异性,可诱发理想的体液及细胞免疫应答,可望成为ＨＣＶＰｆ双价疫苗的候选抗原。     

一种新的gp130结合分子的序列分析和真核表达

目的对以ＧＳＴ－ｇｐ１３０融合蛋白为探针，筛选人胎盘ｃＤＮＡ文库而得到的一个分子（ＧＡＭ，ｇｐ１３０ａｓｓｏｃｉａｔｅｄｍｏｌｅｃｕｌｅ）ｃＤＮＡ序列进行测定并做真核表达。方法进行噬菌体制备及克隆测序，并做同源性检索和构型、亲水性分析，ＣＯＳ细胞转染和３５Ｓ－蛋氨酸标记。结果所得ＧＡＭ分子与另一已克隆成功但功能还不清楚的称为ｈＡＥＳ－１的分子同源性达９７．７％。此外，ＧＡＭｃＤＮＡ还与果蝇ｅｎｈａｎｃｅｒｏｆｓｐｌｉｔ基因相关的分子有较高同源性。ＧＡＭ分子具有一个５８８个核苷酸的开放读框，编码１９６个氨基酸。将ＧＡＭ分子ｃＤＮＡ转染ＣＯＳ细胞后，细胞裂解液电泳可见一分子量约为２４×１０３的表达带，与预期的分子量相符合。结论ＧＡＭ分子与ｈＡＥＳ－１分子在开放读框内仅相差一个氨基酸（且不排除测序的个别错误），其分子量也与已报道的ｈＡＥＳ－１分子量相同，故认为两者很可能是同一分子。     

中华鳖MHC Iα2链基因克隆及序列分析

目的：为了探明中华鳖ＭＨＣ的结构与功能和寻找该种群的分子标记，对中华鳖ＭＨＣｃｌａｓＩα２基因中由两个半胱氨酸形成二硫键的区域进行了克隆和序列分析。方法：根据人和动物的ＭＨＣＩａα２链中两个半胱氨酸侧翼的保守序列设计了混合型引物，采用ＰＣＲ法从中华鳖基因组ＤＮＡ中克隆了ＭＨＣＩα２链（ＴｒｓｉＢＸ１）。结果：经氨基酸序列的同源性分析，ＴｒｓｉＢＸ１存在抗原多肽结合位点（Ｔ１４３、Ｋ１４６、Ｗ１４７、Ｙ１５９）以及β２微球蛋白结合位点（Ｑ１１５、Ａ１１７、Ｄ１１９、Ｇ１２０、Ｄ１２２），并与人和动物的ＭＨＣＩａα２存在４１１％～６３９％同源性。结论：ＴｒｓｉＢＸ１属ＭＨＣｃｌａｓｓＩａ类基因，可作为中华鳖种群的分子标记。     

抑制性底物杂交(SSH)技术研究BXSB小鼠的差异表达基因

目的：利用抑制性底物杂交技术（Ｓｕｐｐｒｅｓｓｉｏｎ ｓｕｂｔｒａｃｔｉｖｅ ｈｙｂｒｉｄｉｚａｔｉｏｎ，ＳＳＨ），以ＢＸＳＢ狼疮小鼠为模型，研究系统性红斑狼（ＳＬＥ）发病相关基因。方法：分离ＢＸＳＢ和Ｃ５７－ＢＬ－６小鼠骨髓细胞，ｍＲＮＡ，反转录构建ｃＤＮＡ文库，利用技术研究ＢＸＳＢ小鼠差异表达基因。结果：获得了１２个阳性克隆，其中有３个克隆编码ＴＣＲ、ＭＨＣⅡ类分子及逆转录病毒基因表达产物，均     

抗内毒素单链抗体基因的构建、序列分析及表达

目的：构建抗内毒素（ＬＰＳ） 单链抗体基因, 并尝试其在Ｅ．ｃｏｌｉ 中的表达。方法： 采用ｌｉｎｋｅｒ Ｐｒｉｍ ｅｒ Ｍｉｘ ,按ＶＨｌｉｎｋｅｒＶＬ 的结构将鼠抗ＬＰＳ ｍ Ａｂ Ｃ３Ａ２ 的ＶＨ ,ＶＬ 基因拼接成单链抗体（ＳｃＦｖ） 基因;用ＰＥ３７３Ａ 型全自动ＤＮＡ序列分析仪测定其核苷酸序列。ＰＣＲ 扩增抗ＬＰＳ ＳｃＦｖ 基因并更换两端接头序列后,插入谷胱甘肽巯基转移酶（ＧＳＴ）融合表达载体ｐＧＥＸ４Ｔ１ ;转染Ｅ．ｃｏｌｉ ＪＭ１０９ ,以ＩＰＴＧ 诱导表达,ＳＤＳＰＡＧＥ 分析表达产物。结果：扩增出的ＳｃＦｖ基因长７３５ｂｐ , 序列分析表明,该序列完整、正确;ＳＤＳＰＡＧＥ 显示,转染入重组质粒ｐ４ＴＣ３Ａ２Ｆｖ 的ＪＭ１０９ 菌经诱导后,有相对分子质量（ Ｍｒ） 约为５２ ０００ 的外源蛋白表达。结论：成功地构建了鼠抗ＬＰＳ ＳｃＦｖ 基因,并在Ｅ．ｃｏｌｉ ＪＭ１０９中表达了ＧＳＴＳｃＦｖ 融合蛋白。     

新的识别人活化B细胞分化抗原5C5单克隆抗体（5C5－G＿1）的制备和鉴定

新制备的抗人活化Ｂ细胞分化抗原５Ｃ５单克隆抗体５Ｃ５－Ｇ＿１经Ｗｅｓｔｅｒ印迹分析表明，该分化抗原经ＳＤＳ－ＰＡＧＥ（还原条件下）显示五条带，分子量分别为９２ｋＤ、５２ｋＤ±（两条）、４０ｋＤ和２０ｋＤ。用单抗５Ｃ５和单抗５Ｃ５－Ｇ＿１的混合物，从３Ｄ５细胞的λｇｔｌｌｃＤＮＡ文库中筛选到７个阳性ｃＤＮＡ克隆。     

三种抗G—CSF单链抗体基因的表达及活性鉴定

从重组人ＧＣＳＦ免疫小鼠全套单链抗体噬菌体表面展示文库中, 筛选到３ 个具有ＧＣＳＦ抗原结合活性的重组噬菌体单链抗体基因。将其感染不含Ｓｕｐ Ｅ的Ｅ． ｃｏｌｉ 菌株, 获得以ＳｃＦｖＥｔａｇ 形式的目的抗体片段的可溶性表达。经ＥＬＩＳＡ和Ｄｏｔｂｌｏｔ 检测, 表达产物具有与ＧＣＳＦ抗原结合的活性。ＮＦＳ６０ 细胞株抑制实验初步表明, 表达产物具有抑制ＧＣＳＦ的作用。     

人细胞色素P4502B6的GST融合蛋白及其抗体的制备

目的：获得纯化抗原用于制备ＣＹＰ２Ｂ６多克隆抗体方法：ＰＣＲ扩增目的基因片段,亚克隆入融合蛋白表达载体ＰＧＥＸ－３ｂ,构建了重组质粒ＰＧＥＸ／２Ｂ６。然后将该重组质粒转化大肠杆菌ＤＨ５α,ＩＰＴＧ诱导表达,ＳＤＳ＿ＰＡＧＥ分离,获纯化融合蛋白ＧＳＴ－２Ｂ６。用ＧＳＴ－３Ｂ２免疫ＢＡＬＢ／Ｃ小鼠,自腹水中获取ＣＹＰ２Ｂ６多克隆抗体。结果：融合蛋白ＧＳＴ－２Ｂ６（ＣＹＰ２Ｂ６２０２￣３５２ａａ）,并获     

PCR法检测EB病毒BNLF1基因

目前已建立分子杂交和ＰＣＲ检测ＥｐｓｔｅｉｎＢａｒｒ病毒（ＥＢＶ）ＤＮＡ的方法。近年来研究发现ＥＢＶ致癌作用与ＬＭＰ１蛋白的表达密切相关〔１〕。为此,我们针对ＥＢＶ表达ＬＭＰ１蛋白的ＢＮＬＦ１基因片段建立ＰＣＲ检测方法。１　材料与方法１１　标准病毒和对照病毒　含有ＥＢＶ的Ｒａｊｉ细胞系和带有ＰＧＥＭＩＢＮＬＦ１的菌种有美国国立卫生研究院（ＮＩＨ）Ｊａｃｋｓｏｎ博士赠送。ＨＣＭＶＡＤ１６９、ＨＳＶⅠ、ＶＺＶ购自于上海第二医科大学。１２　主要试剂与仪器　限制性内切酶ＳｔｙＩ,Ｍａｒｋｅｒ购…     

从噬菌体随机肽库筛选CD137结合肽

目的应用噬菌体随机七肽库筛选与人CD137特异结合的肽序列。方法以重组人CD137作为筛选分子，对噬菌体展示随机七肽库进行亲和淘选。经过5轮淘选后，共随机挑选23个噬菌斑并对其进行了扩增和测序，据此推导随机多肽的氨基酸序列。经夹心ELISA进一步鉴定噬菌体克隆与CD137的结合力。^3H-TdR法检测了噬菌体展示多肽对抗CD137Ab刺激的人外周血淋巴细胞增殖反应影响。结果5轮淘选所得的噬菌体回收率逐步提高，显示淘选过程对随机肽库有一定的富集效果。通过对阳性克隆的测序和序列比较分析，得到RPTQGAF、RPTQVAL、RPTQVAF的相似序列和与CD137L具有同源SRS序列的SRSRVRY、HRRPSRS肽序列，ELISA结果显示这5个克隆都有良好的与CD137的结合力。RPTQGAF、RPTQVAL、RPTQVAF和SRSRVRY4个噬菌体展示肽均能在体外抑制抗CD137Ab刺激的淋巴细胞增殖反应。结论通过对噬菌体随机肽库的淘选，得到与CD137结合的相关多肽，为进一步研究CD137与配体结合的特异性位点及其拮抗性多肽药物设计提供了实验依据和结构基础。     

淡色库蚊性别差异表达cDNA文库的构建和分析

目的为探讨媒介与病原、媒介与宿主的相互作用，建立传播疾病的淡色库蚊性别差异表达cDNA文库。从而筛选阻断疾病传播的疫苗候选分子。方法以淡色库蚊雌蚊成蚊为检测方（Tester）、雄蚊成蚊为驱动方（Driver），进行正向抑制性消减杂交；以雄蚊成蚊为Tester、雌蚊成蚊为Driver，进行反向抑制性消减杂交。将获得的正向抑制性消减杂交产物克隆入pGEM-T easy vector，并以菌液PCR扩增鉴定插入片段。随机抽取100个阳性克隆进行DNA序列分析，并将所得ESTs序列进行在线BLAST分析。结果从100个阳性克隆中测得98个ESTs序列，在测定的序列中与已知基因具有同源性的有57个，其余41个ESTs与已知基因不具有同源性。结论抑制性消减杂交技术建立雌蚊特异性基因文库，发现了淡色库蚊雌蚊新的ESTs序列，为性别相关基因的功能及性别调控。探讨媒介与病原、媒介与宿主的相互作用及其筛选传播阻断疫苗候选分子的研究奠定了基础。     

Rapid identification of CD4+ T-cell epitopes using yeast displaying pathogen-derived peptide library

Identification of CD4+ T-cell epitopes is a critical step in studying and modulating the immune responses to tumors, infectious agents, and autoantigens. Here we report a facile, accurate, and high-throughput method for CD4+ T-cell epitope identification using yeast displaying pathogen-derived peptide library. A library of DNA fragments that encode all the possible peptides with 10-20 amino acids from the antigens (single antigenic proteins or pathogenic organisms) are fused to the gene encoding the restriction single-chain MHC class II molecule in a yeast display vector. The resultant library of recombinant yeast cells are analyzed by FACS to identify those containing peptides with high affinity towards the restriction MHC molecule, which are subsequently screened for their ability to induce antigen-specific T-cell activation. DNA sequence analysis of selected positive clones results in direct identification of the antigenic peptides. We show that this method can be used to rapidly pinpoint the HA(306-322) epitope from the haemagglutinin protein and the entire influenza virus X31/A/Aichi/68 genome, respectively.     

Gene Discovery through Expressed Sequence Tag Sequencing in Trypanosoma cruzi

Analysis of expressed sequence tags (ESTs) constitutes a useful approach for gene identification that, in the case of human pathogens, might result in the identification of new targets for chemotherapy and vaccine development. As part of the Trypanosoma cruzi genome project, we have partially sequenced the 5′ ends of 1,949 clones to generate ESTs. The clones were randomly selected from a normalized CL Brener epimastigote cDNA library. A total of 14.6% of the clones were homologous to previously identified T. cruzi genes, while 18.4% had significant matches to genes from other organisms in the database. A total of 67% of the ESTs had no matches in the database, and thus, some of them might be T. cruzi-specific genes. Functional groups of those sequences with matches in the database were constructed according to their putative biological functions. The two largest categories were protein synthesis (23.3%) and cell surface molecules (10.8%). The information reported in this paper should be useful for researchers in the field to analyze genes and proteins of their own interest.     

Recognition of autologous dendritic cells by human NK cells

NK cells can recognize and kill tumor as well as certain normal cells. The outcome of the NK-target interaction is determined by a balance of positive and negative signals initiated by different target cell ligands. We have previously shown that human NK cells kill CD40-transfected tumor targets efficiently, but the physiological significance of this is unclear. We now demonstrate that human NK cells can kill dendritic cells (DC), known to express CD40 and other co-stimulatory molecules. The killing was observed with polyclonal NK cells cultured short term in IL-2 as well as with NK cell clones as effectors, and with allogeneic as well as autologous DC as targets. NK cell recognition could be inhibited, but only partially, by preincubation of target cells with monoclonal antibodies against CD40, suggesting that this molecule may be one of several ligands involved. Addition of TNF-alpha of the cultures stimulated the development of a more mature DC phenotype, while addition of IL-10 resulted in a less mature phenotype, with lower expression of CD40 and other co-stimulatory molecules. Nevertheless, such DC were more NK susceptible than the differentiated DC. This may be partly explained by a reduced MHC class I expression observed on such cells, since blocking of MHC class I molecules on differentiated DC or CD94 receptors of NK cells led to increased NK susceptibility. The results show that NK cells may interact with DC, and suggest that the outcome of such interactions depend on the cytokine milieu.     

多头带绦虫脑多头蚴cDNA表达文库的构建及初步分析

从甘肃景泰羊源脑多头蚴原头节提取总RNA,以Oligo(dT)纤维素柱纯化mRNA,利用Lambda ZAP II XR文库构建试剂盒构建了脑多头蚴cDNA表达文库.从构建的原始文库随机挑选单个噬菌斑进行PCR,确定文库重组率和插入外源基因片段大小,鉴定文库质量.结果表明脑多头蚴cDNA表达文库的原始库容量为1.0×1...