414 research outputs found

    呼吸道合胞病毒融合蛋白(F蛋白)结构及中和表位的研究进展

    Get PDF
    呼吸道合胞病毒(Respiratory syncytial virus,; RSV),是造成全世界范围内婴幼儿下呼吸道感染的主要原因之一,2岁前的幼儿几乎全部感染过RSV,造成肺炎及毛细支气管炎等呼吸道疾病。 0 ~; 2个月的婴儿在感染RSV后易出现严重的病症。而在最新的全球疾病死亡率分析中,1月到1周岁的儿童死亡中约有6.7%是由RSV感染造成的。青壮年人群; 感染后病症较轻,但在老年人群中会出现严重病症及死亡病例。人体被RSV感染后会激发出中和抗体并引发T细胞应答,但免疫能力会随着时间衰退,进而造成终; 身的反复感染。至今没有安全有效的疫苗上市,唯一获准上市的RSV特异性药物是中和单抗Palivizumab; (Synagis~),但由于其价格高昂,中和效价不足致免疫剂量大等原因,目前仅用于降低免疫缺陷和先心病等高危新生儿的患病风险。结构生物学解析显示; Palivizumab能够与一种稳定构象的F蛋白结合,提示F蛋白作为中和抗体靶向蛋白的重要性。国家自然科学基金; 国家自然科学基金委员会(NSFC)与美国国立卫生研究院(NIH)合作研究项

    Fas/Fas L凋亡作用机制

    Get PDF
    Fas(又称APO-1,CD95)及其配体Fas L,诱导编程性死亡的细胞表面分子,参与机体免疫调节。本文主要讨论了Fas/Fas L相互作用诱导细胞凋亡的可能机制,包括表达调控,特异结合蛋白,蛋白水解链等

    Significance of serum IgA in patients with acute hepatitis E virus infection

    Get PDF
    Aim: To study the significance of serum anti-hepatitis E virus (HEV) IgA in patients with hepatitis E. Methods: A new method was established to assay anti-HEV IgA, which could be detected in the middle phase of the infection. We compared anti-HEV IgA assay with anti-HEV IgM and anti-HEV IgG assay in sera from 60 patients with positive HEV-RNA. Results: The 60 patients with positive HEV-RNA had both anti-HEV IgA and anti-HEV IgM and 410 patients with negative HEV-RNA were used as control. Periodic serum samples obtained from 60 patients with hepatitis E were tested for HEV RNA, anti-HEV IgM, anti-HEV IgA and anti-HEV IgG. Their HEV-RNA was detectable in the serum until 20 +/- 11 d. We used anti-HEV IgM and anti-HEV IgA assay to detect HEV infection and positive results Were found in 90 +/- 15 d and 120 +/- 23 d respectively, the positive rate of anti-HEV IgA was higher than that of anti-HEV IgM and HEV-RNA (P<0.05). Conclusion: The duration of anti-HEV IgA in serum is longer than that of anti-HEV IgM, and anti-HEV IgA assay is a good method to detect HEV infection. (C) 2006 The WJG Press. All rights reserved

    生物学中荧光共振能量转移的研究应用进展

    Get PDF
    荧光共振能量转移 (FRET)可用于对生物大分子之间的距离进行定性、定量检测 ,所采用的材料、方法在近年都有了很大的发展 ,在核酸、蛋白质、细胞器结构功能检测、免疫测定、配体 受体相互作用测定等方面都有巧妙而有效的应用 ,应用前景十分广

    Virus-like particle-based vaccine development using Escherichia coli expression system

    Get PDF
    重组病毒样颗粒是病毒衣壳蛋白外源表达的重要形式,形态结构与天然病毒高度相似,位于纳米尺度的大小易于被免疫系统识别,可激发机体产生保护性免疫反应,且不含有病毒基因,因此,是一种理想的疫苗形式,也是基于结构进行疫苗设计的重要结构载体。目前已上市的乙型肝炎疫苗、人乳头瘤病毒疫苗和戊型肝炎疫苗等基因工程疫苗均采用病毒样颗粒形式。大肠杆菌表达系统被广泛用于基因工程药物的生产,具有安全性好、生产周期短、易于放大生产等优点,在病毒样颗粒疫苗应用上具有良好前景。本文综述了利用大肠杆菌研制戊型肝炎疫苗和人乳头瘤病毒疫苗的进展,特别是这些病毒样颗粒疫苗的表达及组装、表位结构特征和临床试验结果。Virus-like particles(VLPs) are generated by the self-assembly of viral structural protein using various expression systems.VLPs ensemble native virus particles in morphology and maintain key immune epitopes as authentic virus.In light of nanometer-sized particles with diameters of 20- 60 nm, VLPs were shown to be a passport to immune recognition, thus being capable of eliciting strong protective immune responses.Recombinant VLP-based vaccines have superior safety profiles due to lack of any viral genome.There are several licensed and highly successful VLP-based vaccines produced using recombinant DNA technology, such as recombinant hepatitis B, human papillomavirus and hepatitis E vaccine.E.coli expression system was well-established in production of biotherapeutics.This production platform for recombinant VLP-based vaccines has many advantages, such as rapid replication cycle and amenability for scale-up for commercial scale production.This review outlines the success of hepatitis E and human papillomavirus vaccines derived from E.coli.We highlight the protein expression, particle assembly, key epitope structure and clinical trials of these VLP-based vaccines.国家自然科学基金项目(30925030;81172885

    Oncolytic virus and cancer therapy

    Get PDF
    溶瘤病毒是目前恶性肿瘤治疗领域中较有前景的新型基因治疗药物,其通过选择性杀伤肿瘤细胞和诱导机体产生特异的抗肿瘤免疫两种途径来实现肿瘤靶向治疗的目的,从而达到较好的抗肿瘤效果。现对溶瘤病毒的溶瘤机制、临床研究、联合治疗和当前挑战及未来展望等方面进行综述。Oncolytic virus are therapeutically promising anticancer viruses that selectively kill cancer cells and induce host anti-tumor immune responses. This review summarizes recent advances and progress in oncolytic virotherapy, including oncolytic mechanism, clinical study, combined therapy, challenges and future prospects.厦门市科技计划项目(3502Z20131001

    科学对待疫苗接种后不良事件

    Get PDF
    疫苗是延长人类平均寿命最有力的工具之一.脊髓灰质炎等多种传染病的发病率和死亡率,是目疫苗的应用成功地从地球上消灭了天花,显著降低前控制传染性疾病最有效的措施之一[1].广泛接种疫苗带来的健康效益,不论对群体或个体而言都是毋庸置疑的.然而,疫苗的发展史也伴随着悲剧:在19世纪晚期,使用神经组织细胞生产的狂犬疫苗预防了大量死亡,但每接种230人中就有1人出现癫痫、麻痹和/或昏迷[2];1942年,数十万美军士兵接种了包含人血清的黄热病疫苗,由于部分人血清中携带乙肝

    戊型肝炎诊断、预防及治疗新进展

    Get PDF
    戊型肝炎由HEV感染导致,是全球最主要的病毒性肝炎之一。传统的观念认为戊型肝炎只流行于发展中国家,而随着研究的逐步深入,人们已经认识到戊型肝炎是一种分布于全球并能带来严重负担的疾病。近年来,随着可靠的诊断试剂和戊型肝炎疫苗的成功上市,相关研究及防控进入了一个新时代

    武汉地区戊型肝炎病毒基因型及ORF3基因序列准种特点

    Get PDF
    目的研究武汉地区戊型肝炎病毒(HEV)基因型及HEV开放读码框架3(ORF3)基因序列的准种特点。方法应用逆转录-巢式聚合酶链反应法(RT-nested-PCR)扩增HEV开放读码框架2(ORF2)的部分序列,选取其中25份进行测序,用Clustal X和Mega软件比较武汉地区HEV序列与4个HEV主要代表株序列;并扩增其中2份HEV开放读码框架3(ORF3)的全部序列,克隆入pMD18-T Vector,其中1例挑选30个克隆进行DNA测序。结果25例HEV-ORF2核苷酸同源性为82.61%~98.55%,与Ⅰ型(缅甸株)、Ⅱ型(墨西哥株)、Ⅲ型(美国株)、Ⅳ型(中国/台湾株)核苷酸同源性分别为76.52%~81.74%、70.43%~73.04%、76.52%~81.16%和84.35%~88.70%。来源于同一患者ORF3区全基因组不同克隆之间的碱基序列同源性为97.97%~99.71%,与Ⅳ型(中国/台湾株)核苷酸同源性为89.86%~99.71%。ORF3区可检出点突变、缺失突变、短序列的插入突变。结论武汉地区散发性戊型肝炎患者以HEVⅣ型感染为主。多克隆测序结果提示患者体内HEV呈现准种群共存,HEV-ORF3 C末端第2个富含脯氨酸区多有点突变,点突变不影响脯氨酸表达,这些变异的临床意义值得进一步研究
    corecore