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排序方式: 共有432条查询结果,搜索用时 15 毫秒
1.
从感染病毒乳鼠脑组织提取总RNA,采用RT-PCR和分子克隆技术将扩增到的G2糖蛋白基因插入含CMV启动子的pcDNA3.1/His质粒载体中,通过脂质体介导转染COS-7细胞,用SDS-PAGE、Western-blot及IFIA方法分别测定表达产物的相对分子量及特异性。结果证明获得正向插入的G2-pcDNA3.1/His重组表达质粒,表达产物的相对分子量为56ku,与理论预期大小一致,并且可与汉坦病毒H8205株的腹水抗体起特异反应。表明构建的G2-pcDNA3.1/His重组质粒所表达的蛋白为中国汉坦病毒株特有,能在哺乳动物细胞中表达并具有抗原性,重组质粒可应用于汉坦病毒的DNA疫苗研究。  相似文献   
2.
Human recombinant neutralizing antibodies against hantaan virus G2 protein   总被引:13,自引:0,他引:13  
Koch J  Liang M  Queitsch I  Kraus AA  Bautz EK 《Virology》2003,308(1):64-73
Old world hantaviruses, causing hemorrhagic fever with renal syndrome (HFRS), still present a public health problem in Asia and Eastern Europe. The majority of cases has been recorded in China. The aim of our study was to generate human recombinant neutralizing antibodies to a hantavirus by phage display technology. To preserve the structural identity of viral protein, the panning procedure was performed on native Hantaan (HTN) (76-118) virus propagated in Vero-E6 cells. In total, five complete human recombinant IgG antibodies were produced in a baculovirus expression system. All of them were able to completely neutralize HTN, and Seoul (SEO) virus in a plaque reduction neutralization test (PRNT). Three of these antibodies could also completely neutralize Dobrava (DOB) virus but not Puumala (PUU) virus. All antibodies bind to Hantaan virus G2 protein localized in the virus envelope. The sequence areas within the HTN (76-118)-G2 protein detected by five selected antibodies were mapped using peptide scans. Two partial epitopes, 916-KVMATIDSF-924 and 954-LVTKDIDFD-963, were recognized, which presumably are of paramount importance for docking of the virus to host cell receptors. A consensus motif 916-KVXATIXSF-924 could be identified by mutational analysis. The neutralizing antibodies to the most widely distributed hantaviruses causing HFRS might be promising candidates for the development of an agent for prevention and treatment of HFRS in patients.  相似文献   
3.
We sequenced the complete S segments of hantaviruses detected from 12 HPS patients living in southern of Brazil. Samples were obtained from patients diagnosed in different years, in distinct areas, and with a broad spectrum of clinical signs. Despite these differences, all the S proteins of hantavirus from Paraná were identical, except for one amino acid substitution. Phylogenetic analyses of the complete S segment nucleotide and amino acid sequences indicated that hantaviruses from Paraná form a distinct clade from those circulating in South and North America. Other hantaviruses from Brazil were not placed in the same clade. The Oligoryzomys nigripes-associated strains ITA37 and ITA38 from Paraguay were found to belong to the same clade as the hantaviruses from Paraná. Paraguay and Paraná state are located at the same latitude and some ecosystems are similar in both places. The geographic position and common rodent hosts could explain this phylogenetic relationship.  相似文献   
4.
目的:研究汉滩病毒(HTNV)G1蛋白胞质区ITAM样基序与Syk的细胞内相互作用。方法:构建用于研究Syk和G1ITAM样基序之间相互作用的哺乳动物细胞双杂交系统,验证G1ITAM样基序与Syk之间是否存在细胞内相互作用。结果:哺乳动物细胞双杂交分析证实G1ITAM样基序在哺乳动物细胞内可以与Syk相互作用;而突变体分析表明,这种相互作用依赖于该基序中两个高度保守的酪氨酸残基的存在。结论:HTNVG1蛋白胞质区高度保守ITAM样基序在体外和哺乳动物细胞内可以与Syk相互作用,为进一步探讨G1蛋白ITAM样基序在HFRS免疫信号传递中的作用及其与血管内皮损伤的关系奠定了基础。  相似文献   
5.
In the present work we identified B-cell epitopes recognized by sera of humans and rodents naturally infected with Andes virus, a hantavirus present in Chile and Argentina. Analysis of patient and rodent sera with overlapping peptides revealed 21 human and rodent epitopes on the three structural proteins. Whereas in the nucleoprotein the region comprising aa 248-260 was shown to be the key determinant of human sera, the major antigenic site of rodent antibody reactivity is located at aa 326-338. In G1, the main epitope recognized by human sera was mapped to aa 14-26, while rodent antibodies bound predominantly to aa 599-611. In contrast, humans and mice had strong responses to three regions in G2 (aa 691-703, aa 918-930, aa 955-967), of which the last two are associated with neutralization of Hantaan virus. This insight affords important information for the development of immunotherapies for the acute phase of hantavirus cardiopulmonary syndrome.  相似文献   
6.
目的克隆我国分离的汉坦病毒A9株L片段全长cDNA,并测定其核苷酸序列.方法用逆转录-聚合酶链反应(RT-PCR)技术分段扩增汉坦病毒A9株全部L片段,用T-A克隆方法进行PCR产物克隆,测定PCR产物的核苷酸序列.通过亚克隆将分段的L片段连接成全长cDNA克隆.结果A9株的基因组L片段长度为6533个核苷酸,腺嘌呤核苷酸和尿嘧啶核苷酸丰富(%A+U=62.47).包含有一个单一的开放读码框架(ORF),编码一个标准的质量为2.46×105的蛋白,含有2151个氨基酸.A9株与76-118、C1-1和C1-2株的同源性最高,达到83.8%.与TULA病毒的关系较远,其核酸序列的同源性为65.8%.将推导的A9株编码的氨基酸序列与其他21种负链RNA病毒的依赖RNA的RNA聚合酶的氨基酸序列以及汉坦病毒几个代表株的L片段氨基酸序列进行比较,显示A9编码的RNA聚合酶也有6个比较保守的区域以及几个极端保守的氨基酸残基.结论汉坦病毒A9株L片段具有和其他汉坦病毒RNA聚合酶相似的核苷酸一级结构,通过对推导的氨基酸分析,该片段具有一些在RNA病毒聚合酶中都存在的保守区域.  相似文献   
7.
We report 3 cases of Puumala virus infection in a family in Switzerland in January 2019. Clinical manifestations of the infection ranged from mild influenza-like illness to fatal disease. This cluster illustrates the wide range of clinical manifestations of Old World hantavirus infections and the challenge of diagnosing travel-related hemorrhagic fevers.  相似文献   
8.
Dobrava virus infection was diagnosed serologically by enzyme-linked immunosorbent and immunofluorescence assays. To determine which hantavirus serotype was involved, sera were analyzed by a focus reduction neutralization test. The clinical data indicated that only pulmonary manifestation was present. Our data support the presence of Dobrava virus infection outside the Balkan region. In conclusion, a previously healthy adult with unexplained pulmonary perfusion failure should be investigated for hantavirus infection. Received: 15 March 1999  相似文献   
9.
将PCR扩增的HTV76-118RNA小片段的cDNA克隆插入到载体pDS56/RBSⅡ-(O)-6His中,通过IPTG诱导表达以及镍螯合层析纯化重组NP,经过SDS-PAGE、免疫转印和ELISA方法分析其蛋白特性,证实该重组NP与毒粒NP相同,均为49.6ku,能与肾综合征出血热(HFRS)患者血清产生特异性反应。以此重组NP作为抗原制备抗NP单克隆抗体,获得两株持续稳定分泌单克隆抗体的杂交瘤细胞株。用抗NPMcAb建立检测IgM抗体的ELISA捕获法。证实纯化重组NP作为抗原,避免了组织培养病毒的感染性和非特异性以及难以标准化的缺点。所建立的ELISA捕获法检测HFRS患者血清中IgM抗体的方法特异性强、敏感性高,可作为HFRS的早期诊断试剂  相似文献   
10.
From January 1988 to September 1989, seven patients (4 girls and 3 boys, aged 3–12 years) with haemorrhagic fever with renal syndrome (HFRS) were hospitalised at the University Children's Hospital in Belgrade. In four patients the disease appeared as a family outbreak, the others were sporadic cases. In six patients the clinical presentation was suggestive of HFRS, as they had fever with headache, myalgia, sore throat and gastrointestinal illness followed by renal abnormalities. However, severe haemorrhagic syndrome with petechia, haematoma, haematemesis and melaena was present in one patient only. Renal disease presented as nephritic syndrome and/or acute renal failure. Five patients recovered after 2–3 weeks without sequellae, one patient had decreased renal function 17 months after the start of the disease and the remaining patient died. In six patients the diagnosis of HFRS was confirmed serologically by a significant rise in antibody titres against hantaviruses, while in the patient with the fatal and fulminant course of the disease, the diagnosis was established on the basis of epidemiological and autopsy findings. We suggest that children living in endemic areas who develop an ill-defined, febrile and gastrointestinal disease with renal dysfunction should be evaluated for HFRS.  相似文献   
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