Identification of <i>ompL</i>1 and <i>lipL</i>32 Genes to Diagnosis of Pathogenic <i>Leptospira</i>spp. Isolated from Cattle

Diagnosis of leptospirosis in Colombia is based on clinical history and serological testing. However, disease symptoms are nonspecific and there is no uniform criteria regarding the qualifications considered positive. Therefore, it is important to identify and characterize genes associated with pathogenicity in native strains for the development of new diagnostic tests and vaccine production. The aim of this study was to identify the ompL1 and lipL32 genes in Leptospira strains isolated from urine samples of cattle. Sixteen strains were obtained from urine samples and, DNA was isolated to perform two Polymerase Chain Reaction (PCR) tests which identified lipL32 and ompL1 genes. As positive control, a reference strain of L. interrogans was used. L. biflexa and Escherichia coli strains were used as a negative control. In 100% of the samples were identified amplicons of 960 bp and 423 bp corresponding to ompL1 and lipL32 genes respectively. Thus, the pathogenic property and conservation of genes in the isolated strains were confirmed. This study is presented as a contribution to the diagnosis of leptospirosis to use these genes as molecular markers of infection. The results of this study might provide clues for future clinical, epidemiological and molecular research leading to implement new diagnostic strategies and to expand knowledge of the pathophysiology of a disease of public health impact on human and animal.

问号钩端螺旋体lipL32/1-lipL41/1融合基因原核表达系统的构建及其应用

目的 :构建问号钩端螺旋体 (简称钩体 ) lip L 32 / 1- lip L 4 1/ 1融合基因及其原核表达系统 ,了解钩体野生株 lip L32和 lip L4 1基因携带和表达情况及钩体患者的血清抗体水平。方法 :采用连接引物 PCR构建 lip L32 / 1- li-p L4 1/ 1融合基因 ,常规方法构建其原核表达系统。采用 SDS- PAGE检测目的重组蛋白 r L ip L32 / 1- r L ip L4 1/ 1表达情况。采用 Western blot鉴定 r Lip L32 / 1- r Lip L4 1/ 1的免疫原性。采用 PCR和 MAT分别检测 97株问号钩体野生株 lip L32和 lip L4 1基因及其表达情况。采用 EL ISA检测 2 2 8例钩体患者血清 lip L32和 lip L4 1基因产物的抗体。结果 :与报道的相关序列比较 ,lip L 32 / 1- lip L 4 1/ 1融合基因核苷酸和氨基酸序列相似性分别为 99.9%和99.8%。目的重组蛋白 r Lip L32 / 1- r Lip L4 1/ 1表达产量约为细菌总蛋白的 10 % ,主要以包涵体形式存在。r L ip L32 /1和 r Lip L4 1/ 1兔抗血清均能与 r L ip L32 / 1- r L ip L4 1/ 1结合。 97.9%和 87.6 %问号钩体野生株分别有 lip L32和 li-p L4 1基因。95 .9%和 84 .5 %问号钩体野生株分别与 r Lip L32 s和 r Lip L4 1s兔抗血清出现效价 ,为 1∶ 4～ 1∶ 12 8的MAT阳性结果。分别有 94 .7%～ 97.4 %和 78.

问号钩端螺旋体属lipL32/1-ompL1/1融合基因的真核表达及其表达产物的免疫反应性

目的 :构建问号钩端螺旋体 (简称钩体 )的融合基因 lip L32 / 1- omp L1/ 1真核表达系统并鉴定表达产物的免疫反应性。方法 :采用连接引物 PCR构建融合基因 lip L32 / 1- omp L1/ 1,克隆测序后构建 lip L32 / 1- omp L1/ 1的毕赤酵母真核表达系统 p PIC9K- lip L32 / 1- omp L1/ 1- P.pastoris GS115。用 MM和 MD平板分离 His+ Mut+型菌落 ,YPD平板筛选出 G4 18高抗性的 His+ Mut+ 转化子。以酵母裂解酶处理的高拷贝转化子 His+ Mut+ 克隆裂解产物为模板 ,5 'AOX1和 3'AOX1为引物 ,用 PCR检测所构建的毕赤酵母工程菌株染色体 DNA中的目的融合基因。在 BMMY培养基中用甲醇诱导目的重组蛋白 r L ip L32 / 1- r Omp L1/ 1表达。采用硫酸铵沉淀 ,Ni- NTA亲和层析提纯培养物上清液中的 r L ip L 32 / 1- r Omp L1/ 1。采用 SDS- PAGE和 Western blot分别检测 r L ip L 32 / 1- r Omp L 1/ 1的产量及其免疫反应性。结果 :获得的 lip L32 / 1- omp L1/ 1融合基因约为 1794 bp。其核苷酸和氨基酸序列与原始lip L32 / 1和 omp L1/ 1基因型比较 ,相似性分别高达 99.94 %和 10 0 %。所构建的真核表达系统可分泌 r Lip L32 / 1-r Omp L1/ 1,SDS- PAGE后位于预期位置处 ,产量约占上清总蛋白的 4 0 %。r Lip L32 /

问号钩端螺旋体lipL32/1-lipL21-OmpL1/2融合基因原核表达及其产物免疫原性分析

目的:构建问号钩端螺旋体(简称钩体)lipL32/1-lipL21-OmpL1/2融合基因及其原核表达系统,优化目的产物表达条件并对表达产物免疫原性进行鉴定。方法:采用连接引物PCR构建lipL32/1-lipL21-OmpL1/2融合基因,并用常规基因工程方法建立其原核表达系统。采用SDS-PAGE及Bio-Rad凝胶图象分析系统,检测目的重组蛋白rLipL32/1-LipL21-OmpL1/2表达量。采用免疫双扩散试验及WesternBlot,鉴定rLipL32/1-LipL21-OmpL1/2的免疫原性。结果:获得了序列正确的lipL32/1-lipL21-OmpL1/2融合基因及其原核表达系统E.coliBL21DE-3pET42a-lipL32/1-lipL21-ompL1/2。表达条件优化后的rLipL32/1-LipL21-OmpL1/2产量为37.78mg/L,是优化前的3.7倍。rLipL32/1-LipL21-OmpL1/2兔抗血清免疫双扩效价为1∶4。rLipL32/1-LipL21-OmpL1/2抗血清能识别rLipL32/1-LipL21-OmpL1/2以及rLipL32/1、rLipL21、rOmpL1/2。rLipL32/1-LipL21-OmpL1/2能与问号钩体56601株全菌兔抗血清以及黄疸出血群、流感伤寒群、波摩那群、秋季群问号钩体感染患者血清出现阳性杂交信号。结论:成功地构建了lipL32/1-lipL21-OmpL1/2融合基因及其原核表达系统,表达产物具有良好的抗原性和交叉免疫反应性,可作为研制通用型问号钩体基因工程疫苗及通用型钩体病血清学检测的抗原。

Genotypic Analysis, Construction of the Expression System and Immunological Identification of the Recombinant Proteins of the LipL32 Gene in the Dominant Serogroups of Leptospira interrogans in China

To investigate the existence of the major outer membrane protein (MOMP) gene LipL32 in 15 dominant Chinese strains of 15 serogroups of Leptospira interrogans and 2 international strains of 2 serogroups of Leptospira biflexa, and to clone and construct the expression system as well as to identify the recombinant proteins, genomic DNAs from strains of leptospira were prepared by routine phenol-chloroform method, and the fragments of the LipL32 gene with the whole length from the strains were amplified with high fidelity PCR. The target amplification products were sequenced after T-A cloning, and the expression system for the genes were thereby constructed. Expression of the recombinant proteins was identified by using SDS-PAGE after induction with IPTG at different dosages. Western blot assays with rabbit antiserum against the whole cell of TR/PatocⅠ of Leptospira and immunized serum with rMOMPs were used to determine the immunoreactivity and immunogenicity of the recombinant proteins. Microscopic agglutination test was used to determine the cross- agglutination titres in rabbit sera immunized with rMOMPs, and the cell adherence model of Leptospira was used to examine the blocking effects of rabbit antisera against these rMOMPs. It was found that the LipL32 gene could be found in all the 17 strains of Leptospira mentioned above with two different genotypes, i.e. LipL32/1 and LipL32/2. Amounts of expressions of rMOMP1 and rMOMP2 after IPTG accounted for 40% and 10% of the total bacterial proteins respectively. Both rMOMP1 and rMOMP2 could combine with the rabbit antiserum against leptospiral TR/PatocⅠ, and could induce the production of agglutination antibodies to these 17 strains of Leptospira with 1∶2 to 1∶64 MAT titres. The rabbit anti-rMOMP1 and anti-MOMP2 antibodies at 1∶2 to 1∶16 dilutions could efficiently block adherence of Leptospira. It concludes that all the Leptospira tested in the present study possess LipL32/1 or LipL32/2 genes, and the constructed expression system can express the rMOMP1 and rMOMP2. These recombinant proteins are showed to have good immunogenicity and satisfactory immunoreactivity.

RGC-32和ZEB1在胃癌组织中的表达

目的探讨补体反应基因-32(RGC-32)与锌指E盒结合蛋白(ZEB1)在胃癌组织中的表达及意义。方法应用免疫组化S-P法分别检测60例胃癌、,60例癌前病变、20例正常胃黏膜组织中RGC-32和ZEB1蛋白的表达情况。结果 RGC-32在胃癌、癌前病变及正常胃黏膜组织中的阳性表达率依次降低,分别为78.3%、41.7%、40.0%(P<0.05)。ZEB1在胃癌、癌前病变及正常胃黏膜组织中的阳性表达率亦依次降低,分别为88.3%、50.0%、20.0%(P<0.05)。胃癌组织中RGC-32和ZEB1的表达与胃癌的病理分化程度、TNM分期和淋巴结转移有关(P<0.05)。胃癌组织、癌前病变组织中的RGC-32与ZEB1表达均呈正相关关系(r=0.568、0.452,P<0.05)。结论 RGC-32、ZEB1的异常表达可能促进胃癌的发生、发展和浸润转移,两者可能作为胃癌诊断和预后判断的指标,有可能成为胃癌治疗的新靶点。

miR-32-5p通过靶向下调EZH2的表达抑制胰腺癌PANC-1细胞的恶性生物学行为与裸鼠移植瘤生长

目的:探究miR-32-5p通过靶向zeste基因增强子人类同源物2(EZH2)对胰腺癌PANC-1细胞恶性生物学行为的影响及其分子机制。方法:利用GEPIA数据库分析胰腺癌组织中EZH2的表达水平及其与患者的预后生存期的关系,并分析miR-32-5p表达与患者临床病理因素的关系。qPCR法检测正常胰腺HPDE6-C7细胞和胰腺癌PANC-1、AsPC-1、SW1990细胞中miR-32-5p和EZH2 mRNA的表达,通过Lipofectamine^(TM)2000将miR-NC、miR-32-5p mimic、miR-32-5p inhibitor、pcDNA-NC、pcDNA EZH2质粒分别转染PANC-1细胞,其分为对照组(不转染)、miR-NC组(转染miR-NC)、miR-32-5p mimic组(转染miR-32-5p mimic)、Anti-miR-32-5p组(转染miR-32-5p inhibitor)、miR-NC+pcDNA-NC组(转染miR-NC+pcDNA-NC)、miR-NC+pcDNA EZH2组(转染miR-NC+pcDNA EZH2)、miR-32-5p mimic+pcDNA-NC组(转染miR-32-5p mimic+pcDNA-NC)、miR-32-5p mimic+pcDNA EZH2组(转染miR-32-5p mimic+pcDNA EZH2)。双荧光素酶报告基因实验验证miR-32-5p与EZH2的靶向关系;MTT法及克隆形成实验检测各组细胞的增殖能力,划痕愈合实验检测各组细胞的迁移能力;Transwell小室实验检测各组细胞的侵袭能力,WB法检测各组细胞EZH2、E-cadherin、N-cadherin的表达;裸鼠成瘤实验检测转染后各组PANC-1细胞移植瘤的生长情况,免疫组化染色法观察移植瘤组织中Ki67和MMP-2的表达。结果:GEPIA数据库显示胰腺癌组织中EZH2的表达水平高于癌旁组织,患者预后生存期与EZH2的表达水平呈负相关(均P<0.05);miR-32-5p表达水平与胰腺癌神经浸润、肿瘤分化程度、TNM分期、淋巴结转移有明显的关联(均P<0.05);与HPDE6-C7细胞相比,PANC-1、AsPC-1、SW1990细胞中miR-32-5p呈高表达、EZH2 mRNA呈低表达、miR-32-5p表达水平与EZH2表达水平呈负相关(均P<0.05)。miR-32-5p靶向EZH2且抑制其表达(均P<0.05);过表达miR-32-5p能够下调Ki67、MMP-2、N-cadherin表达水平、上调E-cadherin表达水平,抑制PANC-1细胞的增殖、迁移和侵袭能力,抑制移植瘤质量增加(均P<0.05)。结论:miR-32-5p能够靶向调控EZH2从而影响胰腺癌PANC-1细胞的增殖、迁移、侵袭、EMT进程及裸鼠体内移植瘤的生长。

Evolutionary Implication of Outer Membrane Lipoprotein-Encoding Genes ompL1,lipL32 and lipL41 of Pathogenic Leptospira Species

Leptospirosis is recognized as the most widespread zoonosis with a global distribution. In this study, the antigenic variation in Leptospira interrogans and Leptospira borgpetersenii isolated from human urine and field rat kidney was preliminarily confirmed by microscopic agglutination test using monoclonal antibodies, and was further subjected to amplification and identification of outer membrane lipoproreins with structural gene variation. Sequence similarity analysis revealed that these protein sequences, namely OmpL1, LipL32 and LipL41, showed no more homologies to outer membrane lipoproteins of non-pathogenic Leptospira and other closely related Spirochetes, but showed a strong identity within L. interrogans, suggesting intra-specific phylogenetic lineages that might be originated from a common pathogenic leptospiral origin. Moreover, the ompL1 gene showed more antigenic variation than lipL32 and lipL41 due to less conservation in secondary structural evolution within closely related species. Phylogenetically, ompL1 and lipL4l of these strains gave a considerable proximity to L. weilii and L. santaro- sai. The ompI,1 gene of L. interrogans clustered distinctly from other pathogenic and non-pathogenic leptospiral species. The diversity of ompL genes has been an- alyzed and it envisaged that sequence-specific variations at antigenic determinant sites would result in slow evolutionary changes along with new serovar origination within closely related species. Thus, a crucial work on effective recombinant vaccine development and engineered antibodies will hopefully meet to solve the therapeutic challenges.

LncRNA牛磺酸上调基因1通过miR-32靶向COL5A1对TPC-1细胞的影响

目的探究牛磺酸上调基因1(taurine upregulated gene 1,TUG1)对乳头状甲状腺癌(papillary thyroid carcinoma,PTC)-1细胞生长、侵袭和迁移及体内成瘤的影响及其作用机制。方法检测TUG1和miR-32在正常细胞系和甲状腺癌细胞系中的表达;检测沉默TUG1对细胞生长、侵袭和迁移的影响;荧光素酶报告实验检测miR-32与C0L5A1靶向关系;检测COL5A1蛋白表达和细胞增殖、凋亡、侵袭和迁移能力;建立裸鼠移植瘤模型,检测沉默TUG1后肿瘤组织体积、重量和TUG1、miR-32、Ki67、VEGF、COLSA1表达。结果TUG1在甲状腺癌组织和细胞系中高表达,miR-32低表达。沉默TUG1抑制TPC-1细胞增殖、侵袭和迁移,促进细胞凋亡。miR-32和C0L5A1存在靶向关系。沉默TUGI逆转了miR-32 inhibi-tor对细胞增殖、凋亡、侵袭和迁移的作用,并降低肿瘤体积和重量,下调TUG1表达、上调miR-32表达,降低Ki67、VEGF和COL5A1表达。结论TUG1通过miR-32靶向下调C0L5A1调节TPC-1细胞生长、转移和肿瘤形成。

交通警察血铅水平及其相关因素的研究

为了解交警血铅水平及影响因素，对可能影响血铅（ Ｙ）的因素即外勤年限（ Ｘ１）、尿铅（ Ｘ２）、血红蛋白（ Ｘ３）、吸烟与否（ Ｘ４ ）、血锌（ Ｘ５）及年龄（ Ｘ６）进行了单因素相关和多因素逐步回归分析。结果表明交警血铅和尿铅均数为１１９７９μｇ／ Ｌ和６９９ μｇ／ Ｌ，与对照组（８８３８ μｇ／ Ｌ和５３４ μｇ／ Ｌ）差异有显著性。单因素分析表明血铅与外勤年限、尿铅和年龄呈正相关，与血红蛋白呈负相关，多元逐步回归方程为： Ｙ＝ １３２．９５＋ ０．９３ Ｘ１＋ １０．０１ Ｘ２－ ０．８６ Ｘ３＋ ７．３７ Ｘ４ ＋ １４．３０ Ｘ５。交警血铅有随外勤年限增加呈升高趋势，且使血红蛋白合成受到一定程度抑制。