人白细胞介素18的原核表达及多克隆抗体的制备

目的：在原核系统中表达并纯化人白细胞介素18（hIL-18)，制备兔抗人白细胞介素18多克隆抗体，方法：用RT－PCR扩增出hIL-18的cDNA克隆到原核表达载体pJW2中，转化大肠杆菌JM101中诱导表达并纯化。用纯化的人白细胞介素18免疫新西兰兔制备多克隆抗体，结果：克隆得到序列正确的IL-18 cDNA，与载体连接后转化入大肠杆菌JM101中诱导表达并成功纯化，并用纯化的人白细胞介素18成功制备了兔抗人白细胞介素18多克隆抗体。结论：制备的多克隆抗体为下阶段的研究提供了重要的实验材料。     

hIL－16cDNA的克隆、测序及在E.coli中的表达与纯化研究

在国内首次从人的外周血单个核细胞（PBMC）中克隆了人白细胞介素－16(hIL－16)cDNA,并应用一种新型的大肠杆菌表达系统─硫氧还蛋白表达系统,成功地表达了重组hIL－16。hIL－16cDNA的扩增从人PBMC中提取总RNA,poly(T)8－12反转录cDNA,以半巢式PCR扩增出特异的DNA片段。hIL－16cDNA的克隆、测序与表达利用     

白细胞介素4(IgG1诱导因子):一种亦作用于T细胞的多功能淋巴因子

细胞毒和辅助T细胞的生长均需白细胞介素2(IL-2);同时,B淋巴细胞也能表达IL-2受体(IL-2R),IL-2与IL-2R的相互作用可调节B细胞的功能,最近已获得白细胞介素4(IL-4;IgGl诱导因子)的cDNA克隆,重组IL-4(rIL-4)     

IL-13是一种新的能调节炎症反应及免疫应答的人类淋巴因子

本文作者运用不同的方法—筛选cDNA文库,克隆出表达于活化的t淋巴细胞的白细胞介素-13(IL-13),并将IL-13基因定位于人类第5号染色体5q23-31。 首先作者通过分化筛选的方法克隆出编码一种新的细胞因子的cDNA,此蛋白在1993年Keystore细胞因子专题讨论会上被命名为白细胞介素13(IL13),IL-13 cDNA是一个具有2个蛋氨酸起始的同源顺序CCA/GCCAUGG相连。推测出的IL-13多肽的氨基末端与其他分泌蛋白相似,亦呈疏水性,而     

小鼠IL-6具有多种生物活性

迄今对白细胞介素6(IL-6)的研究尚仅局限于人类,未在小鼠中发现人IL-6的类似物。本文作者首次以人IL-6 cDNA为探针从小鼠骨髓基质细胞中分离到小鼠IL-6 cDNA克隆,证明了它     

人类白细胞介素7:分子克隆及其对人类和小鼠 B 细胞系的生长因子活性

白细胞介素7(IL-7)首先是在小鼠骨髓基质细胞培养中发现的一种B 细胞前体生长因子,最近作者已经成功地克隆出小鼠IL-7cDNA,由此编码出的重组的小鼠IL-7可促进前B 细胞和原B 细胞的生长。本文作者利用小鼠IL-7cDNA 作探针来检测人类肝癌细胞系的cDNA 文库,分离出一株与小     

白细胞间介素—2受体

白细胞间介素-2(IL-2)是在巨噬细胞分泌的白细胞间介素-1(IL-1)存在下,由抗原/丝裂原活化某些 T 细胞合成和分泌的一种淋巴因子。在体外,IL-2能刺激活化 T细胞克隆的长期生长,增强胸腺细胞的有丝分裂反应,诱导胞毒性 T 细胞活性和增强裸鼠脾细胞培养中的空班形成细胞反应。在体内,IL-2可能用于治疗一些免疫性疾病如获     

正常β细胞前体对小鼠重组IL-7的应答及TGF-β对IL-7活性的抑制

B细胞前体的生长与分化是受到一系列的可溶性因子包括IL-1、IL-3、IFN-γ及B细胞成熟因子的刺激后方可进行。最近已从支持淋巴细胞生长的转化的骨髓基质细胞培养上清中,纯化出一种能维持淋巴细胞克隆持续增殖的新型细胞因子——白细胞介素-7(IL-7)。尽管已成功地克隆出IL-7cDNA,并进行了测序分析,但是对于IL-7     

白细胞介素-7的研究进展

IL-7是一种多功能的新型白细胞介素,它既可作用于前B 细胞,促进其增殖、分化;又可作用于T 细胞,诱导其表达IL-2受体并产生IL-2。本文主要从IL-7的制备与活性检测、IL-7 cDNA 的克隆及IL-7的生物学活性等方面介绍了近年来有关IL-7的研究进展。     

hIL—16cDNA的克隆,测序及在E.coli中的表达与纯化研究

在国内首次从人的外周血单个核细胞（PBMC）中克隆了人白细胞介素—16（hIL－16）cDNA,并应用一种新型的大肠杆菌表达系统一硫氧还蛋白表达系统,成功地表达了重组hIL-16。hIL-16cDNA的扩增：从人PBMC中提取总RNA,poly（T）8-12反转录cDNA,以半巢式PCR扩增出特异的DNA片段。hIL-16cDNA的克隆、测序与表达：利用E．coli表达载体pTrxFus,构建hIL－16。DNA的重组质粒,转化E．coli后,经色氨酸诱导,表达出相对分子质量（Mr）为30000的可溶性融合蛋白,表达量占菌体蛋白的30％。序列测定证实,此片段长393bp,确为hIL-16cDNA。经一步渗透压休克,即获得了高纯度的表达蛋白。     

小鼠巨噬细胞cDNA酵母表达文库的构建与鉴定

目的 采用Gateway技术构建适合酵母表达的小鼠巨噬细胞cDNA文库并进行鉴定.方法 将小鼠巨噬细胞的mRNA分离纯化后,以生物素标记的寡聚胸苷酸Oligo(dT)为引物反转录后连接attB衔接子(attB Adapter),层析柱纯化,通过BP重组反应将500 bp以上的片段克隆到含attP衔接子的pDONRTM222载体,电转化入ElectroMAXTM DH10BTMT1 Phage Resistant Cells,构建Gateway入门cDNA文库,并完全随机挑取单菌落,提取质粒酶切鉴定重组子插入片段大小.构建Gateway目的 载体,通过LR重组反应将入门文库转入此目的 载体成为酵母表达文库,挑取单克隆鉴定重组子插入片段大小.结果 经鉴定,入门文库平均滴度为(6.80±0.10)×105 cfu/ml,文库总容量为7.48×106 cfu,平均插入片段为(2.20±0.20)kb,重组率为100%.酵母表达文库平均滴度为(3.24±0.10)×106 cfu/ml,文库总容量为3.89×107 cfu,平均插入的片段为(2.27±0.15)kb,重组率为95.83%(23/24).结论 构建的小鼠巨噬细胞cDNA入门文库和酵母表达文库都符合高质量文库的要求,可用于进一步的研究.     

小鼠端粒酶蛋白亚单位真核表达载体的构建和序列测定

目的： 克隆小鼠端粒酶蛋白亚单位(mTERT)的cDNA，构建真核表达载体并进行序列测定。 方法: 从肝癌细胞中提取总RNA，采用RT-PCR 技术扩增mTERT的基因编码区序列，将序列定向克隆至真核表达载体pAC，并进行序列测定。 结果： 获得mTERT编码区 3 369 bp的cDNA片段，用PCR和限制性内切酶分析鉴定，表明获得重组质粒pAC-mTERT。通过对mTERT编码区cDNA序列测序证实其与GenBank中的已知序列一致。 结论： 成功克隆了mTERT编码区序列，并构建了其真核表达载体，为以TERT为基础的肿瘤生物治疗奠定基础。     

Human complement factor H: isolation of cDNA clones and partial cDNA sequence of the 38-kDa tryptic fragment containing the binding site for C3b

We isolated cDNA clones coding for the functionally important tryptic N-terminal 38-kDa fragment of human complement control protein factor H using polyclonal and monoclonal antibodies to screen a human liver cDNA library cloned in a bacterial expression vector, PEX-1. By testing the reactivity of antibodies specific for the recombinant proteins produced by individual clones with proteolytic fragments of serum H the exact position of these cDNA clones within H was mapped. One clone, H-19, coding for the 38-kDa fragment of H was sequenced and found to code for 289 amino acids derived from the 38-kDa N-terminal fragment as well as for the first 108 amino acids belonging to the complementary 142-kDa tryptic fragment. The derived protein sequence could be arranged in 6 highly homologous repeats of about 60 amino acids each, the homology between the repeats being determined by the characteristic position of cysteine, proline, glycine, tyrosine and tryptophane residues. The region coding for the epitope recognized by one of our monoclonal antibodies was localized by subcloning restriction fragments of H-19 into the expression plasmid and testing for the expression of this epitope.     

小鼠IL-23基因的克隆和在逆转录病毒中的表达

从肿瘤组织 (含有活化的淋巴细胞 )提取总RNA ,经逆转录多聚酶链反应 (RT PCR )获得小鼠IL 2 3cDNA。经DNA测序分析 ,证实该片段与GeneBank记载的IL 2 3cDNA序列一致。将该目的基因插入LXSN逆转录病毒载体 ,并转染大肠杆菌DH5α中扩增 ,再感染 ψ2 (ecotropic )和PA317(amphotropic )两种包装细胞 ,经G4 18筛选后获得表达IL 2 3分子的PA317阳性细胞克隆。通过用PCR、RT PCR及Northernblot技术检测目的基因表达 ,结果表明 ,成功地将鼠IL 2 3cDNA插入逆转录病毒载体 ,经转染两种包装细胞产生了高表达IL 2 3的PA317细胞克隆。该克隆细胞产生的逆转录病毒可进一步用于转染肿瘤细胞 ,为制备肿瘤疫苗奠定了基础     

抑制性消减杂交技术筛选重组IFNβ下调HepG2细胞靶基因

目的利用抑制性消减杂交（SSH）技术构建重组干扰素β（IFNβ）刺激人肝癌细胞系HepG2差异表达基因的cDNA消减文库，筛选IFNβ下凋HepG2相关基因。方法重组IFNβ2000U／ml刺激对数生长期HepG2细胞，以生理盐水作用的HepG2细胞为阴性对照；制备细胞裂解液，从中提取mRNA并逆转录为cDNA，经Rsa Ⅰ酶切后将实验组cDNA分成两份，分别与两种不同的接头连接，再与对照组cDNA进行两次消减杂交及两次抑制性PCR，将产物与T／A载体连接，构建cDNA消减文库，并转染大肠埃希菌进行文库扩增，随机挑选克隆PCR后进行测序及同源性分析。结果成功构建重组IFNβ刺激HepG2细胞差异表达基因的cDNA消减文库。文库扩增后，得到58个阳性克隆，进行菌落PCR分析，均得到200～1000bp插入片段。随机挑选其中35个插入片段测序，并通过生物信息学分析，结果共获得12种编码基因。结论应用SSH技术成功构建了IFNβ刺激HepG2细胞差异表达基因的cDNA消减文库，为进一步了解IFNβ在肝细胞内的免疫调节机制提供了依据。     

Genomic cloning and partial characterization of human chymotrypsinogen gene

Summary Chymotrypsinogen is a principal precursor of pancreatic proteolytic enzymes. We previously isolated a cDNA clone for human prechymotrypsinogen from a human pancreatic cDNA library. In the present study, we used this cDNA sequences to isolate genomic DNA clones. Three overlapping cosmid clones spanning approximately 65-kb genomic sequences were isolated from a human cosmid library. The genomic DNA clones were characterized by restriction enzyme mapping and by hybridizing them to subfragments of the cDNA. The sequence tagged sites for human chymotrypsinogen gene were created by designing two oligonucleotides. Furthermore, the isolated genomic clones were confirmed to be localized on chromosome 16q23 by fluorescencein situ hybridization and G-banding analysis.     

Molecular cloning of cDNAs expressing SS-B/La protein

Using serum from a patient with Sj?gren's syndrome containing a high titer of anti-SS-B/La antibody, cDNA clones (a representative clone was called pA158) were isolated from a human fibroblast cDNA library in lambda gt11 expression vector. After subcloning of pA158 cDNA into an expression plasmid vector pEX-2, a large amount of the recombinant fusion protein with cro-beta-galactosidase (called pA158EX) was obtained in E. coli culture containing the recombinant pEX-2. Antibodies against pA158EX were purified from the patient serum by Sepharose 4B conjugated with the purified pA158EX protein. Immunofluorescent staining of HEp-2 cells with the anti-pA158EX antibodies showed a speckled nuclear staining. In immunoblot analysis, the anti-pA158EX antibodies reacted with 50 kDa protein that was compatible with SS-B/La protein. Immunoprecipitation of leukocyte lysate with the anti-pA158EX antibodies and the following RNA analysis showed that the antibody precipitated Y5 RNA. These findings indicate pA158 is a cDNA for SS-B/La protein. The purified fusion protein was used for enzyme-linked immunosorbent assay (ELISA). Optical density values of anti-SS-B positive sera were high, but those of anti-SS-B negative sera and healthy donor sera were low. In the Northern blot using human RNA and pA158 cDNA, a single band about 1.8 kb was recognized. A full-length cDNA was further obtained by screening of pcD library using pA158 cDNA as a probe.     

小鼠FasL全长cDNA的克隆与FasL腺病毒载体的构建

目的: 克隆小鼠FasL全长cDNA, 构建FasL腺病毒载体。方法: 从经ConA(5mg/L)刺激 48h的BALB/c小鼠脾脏单个核细胞中克隆FasL全长cDNA, 构建以CMV启动子转录调控的含小鼠FasL全长cDNA的穿梭质粒mFasL pAdTrack。经PacI酶切后, 与腺病毒骨架质粒pAdEasy 1在大肠杆菌BJ5183中进行同源重组。挑选阳性重组子转染HEK- 293细胞, 构建CMV启动子转录调控的mFasL重组腺病毒载体。结果: 成功地克隆小鼠FasL全长cDNA, 经PCR、酶切及荧光检测等证实, 成功地构建了重组mFasL腺病毒载体。结论: 重组FasL腺病毒载体的构建为进一步研究FasL在肿瘤和自身免疫性疾病的作用奠定了基础。     

Cloning of cDNA for the bovine IL-2 receptor (bovine Tac antigen).

We have cloned the Tac analog of the bovine IL-2 receptor (IL-2R) cDNA. Using mouse and human cDNA probes, we isolated five bovine IL-2R clones from a lambda gt11 bovine long-term lymphocyte cDNA library. Three of the clones had inserts of 2600 base pairs (bp), the same size as the bovine IL-2R mRNA visualized on Northern blots. The full-length cDNA contain a 190-bp 5' untranslated region, followed by a 825-bp coding region, and a 3' untranslated region that contain 1600 bp. Comparison of the bovine and human IL-2R-coding sequences revealed 71% homology at the nucleotide level. The 3' and 5' non-coding regions were not as homologous, apart from a specific site in the 5'-untranslated region that contained a 5'-upstream start codon. In this region, 24 of 26 nucleotides were identical for the human and bovine cDNAs. Further analysis of the bovine IL-2R sequence also revealed the following: (i) the hydrophobic domains of the IL-2R protein were more conserved between species than the hydrophilic domains, (ii) the predominant site of intracellular IL-2R phosphorylation in mouse and human was a conserved Ser which was not conserved in the bovine sequence, and (iii) there exists a statistically significant amino acid homology with the AIDS gag protein.     

恶性疟原虫疫苗研究VIPfCMR基因与人白细胞介素-2基因的连接与克隆

用限制性内切酶ＥｃｏＲＩ和ＳａｌＩ将恶性疟原虫复合抗原基因ＰｆＣＭＲ从质粒ｐＷＲ４５０－１／ＰｆＣＭＲ中切下，插入质粒ｐＢＶ２２０／ＩＬ－２中人白细胞介素－２（ＩＬ－２）基因的ＥｃｏＲＩ位点。重组质粒转化大肠杆菌ＤＨ５ａ，通过ＰＣＲ扩增和酶切鉴定，筛选出正向插入的重组载体ｐＢＶ２２０／ＰｆＣＭＲ－ＩＬ－２。为表达ＰｆＣＭＲ－ＩＬ－２融合蛋白打下基础。