呼吸道合胞病毒疫苗增强性疾病小鼠模型的建立与评价

呼吸道合胞病毒(respiratory syncytial virus,RSV)是导致婴幼儿严重下呼吸道感染的最重要病原体,但该病毒的灭活疫苗可引起RSV疫苗增强性疾病(RSV vaccine-enhanced disease,RVED),因此至今仍未研制出安全、有效的疫苗。RVED的发生机制目前仍不清楚。使用能有效模拟RVED的动物模型是探索RVED发生机制的主要手段,而本研究的目的就是建立能稳定模拟RVED表现的小鼠模型。将BALB/c小鼠分成3组,即甲醛灭活RSV疫苗接种组(FV组)、活RSV接种组(VV组)和对照组(BV组),并模拟自然感染对其攻毒。通过小鼠体重监测、肺组织苏木精-伊红染色、荧光定量聚合酶链反应(polymerase chain reaction,PCR)、流式细胞术等,观察FV组小鼠感染RSV后的病毒载量、肺部炎症和T细胞免疫状态。结果显示,与VV组和BV组相比,FV组小鼠RSV攻毒后的体重占初始体重百分比显著降低,肺部炎症最明显,且仅FV组出现支气管和毛细血管周围有大量淋巴细胞浸润及嗜酸性粒细胞浸润。荧光定量PCR显示,FV组小鼠的肺部RSV载量最低。流式细胞术显示,攻毒4d后FV组CD~(4+) T细胞数与其他两组相比显著增加,且CD~(4+) T细胞分泌的白细胞介素4(interleukin 4,IL-4)及IL-4/γ干扰素(interferonγ,IFN-γ)比值显著高于其他两组,而CD~(8+) T细胞分泌的肿瘤坏死因子α(tumor necrosis factorα,TNF-α)和IFN-γ低于VV组。结果提示,RVED小鼠呈现出Th2优势型免疫应答及CD~(8+) T细胞功能不足,模型初步建立成功,为RVED发生机制的探索和RSV疫苗的研发奠定了良好基础。     

呼吸道合胞病毒IgG酶联检测试剂盒的研制

为了研制检测呼吸道合胞病毒IgG的酶联检测试剂盒,以呼吸道合胞病毒Long株病毒液作为包被抗原,HRP标记羊抗人IgG作为信号抗体,制备ELISA抗体检测试剂盒。结果表明建立的RSV酶联检测试剂盒敏感性与进口试剂盒接近,特异性达 95. 24%,重复性好,批内变异系数为 6. 35%,试剂盒置于 37℃ 0天与 7天检测结果无显著差异。成功制备了RSVIgG酶联检测试剂盒。     

Toll 样受体通路激活改善呼吸道合胞病毒疫苗诱导免疫应答的研究进展

呼吸道合胞病毒（RSV）是导致婴幼儿严重下呼吸道感染的最重要病原体,但该病毒的灭活疫苗可引起RSV疫苗增强性疾病（RVED）。RVED的机制目前仍不清楚。Toll样受体（TLR）及其信号转导对 RSV的识别和宿主免疫的激发均有重要作用,其在RVED机制中的作用也日益受到关注。本文主要介绍TLR在抗RSV天然免疫和获得性免疫中的角色及其信号通路激活状态改变对RVED免疫格局的影响,提示RVED机制可能与TLR信号通路激活不足有关,从而为RSV疫苗研制提供新的策略和方法。     

呼吸道合胞病毒感染促进豚鼠产生气道高反应性及其机制研究

目的：通过检测气道反应性和M2受体功能,研究呼吸道合胞病毒（RSV）感染与哮喘发病的关系及机制。方法：34只豚鼠随机分为4组：Hep-2滴鼻＋生理盐水雾化（Hep-2／NS,A）组,RSV滴鼻＋生理盐水雾化（RSV／NS,B）组,Hep-2滴鼻＋鸡卵蛋白（OVA）雾化（Hep-2／OVA,C）组和RSV滴鼻＋OVA雾化（RSV／OVA,D）组,其中A和B纽各9只,C和D组各8只,以A组为对照组。21d通过电刺激迷走神经检测各组气道反应性和M2受体功能,行嗜酸性粒细胞计数以及病理学观察。结果：B组气道内压力（mmH2O）与A组无明显差异（P〉0．05）,给予匹罗卡品,IP下降幅度高于A组,但差别无显著性（P〉0．05）。C组IP明显高于A且（P〈0．05）,且给予匹罗卡品,IP下降幅度明显低于A组,差别有显著性（P〈0．05）。D组IP明显高于C组（P〈0．05）,给予匹罗卡品后IP下降幅度明显低于C组（P〈0．05）。结论：RSV感染可促进过敏原引起的M2R功能障碍,从而促进AHR发生。     

Direct visualization of the small hydrophobic protein of human respiratory syncytial virus reveals the structural basis for membrane permeability

Human respiratory syncytial virus (HRSV) is the leading cause of lower respiratory tract disease in infants. The HRSV small hydrophobic (SH) protein plays an important role in HRSV pathogenesis, although its mode of action is unclear. Analysis of the ability of SH protein to induce membrane permeability and form homo-oligomers suggests it acts as a viroporin. For the first time, we directly observed functional SH protein using electron microscopy, which revealed SH forms multimeric ring-like objects with a prominent central stained region. Based on current and existing functional data, we propose this region represents the channel that mediates membrane permeability.

Structured summary

MINT-7890792, MINT-7890805: SH (uniprotkb:P04852) and SH (uniprotkb:P04852) bind (MI:0407) by chromatography technology (MI:0091)MINT-7890784, MINT-7890776: SH (uniprotkb:P04852) and SH (uniprotkb:P04852) bind (MI:0407) by electron microscopy (MI:0040)     

Neonatal vaccination against respiratory syncytial virus infection

Respiratory syncytial virus (RSV) is the leading cause of pneumonia and bronchiolitis in infants and is the most frequent cause of lower respiratory tract infections in children.Efficacious vaccination...     

Protection against respiratory syncytial virus (RSV) elicited in mice by plasmid DNA immunisation encoding a secreted RSV G protein-derived antigen

Plasmid vectors encoding two different variants, one cytoplasmic and one secreted version, of a candidate vaccine BBG2Na to respiratory syncytial virus (RSV), were constructed and evaluated in a nucleic acid vaccination study. The two different vectors, which employed the Semliki Forest virus gene amplification system, were found to express BBG2Na appropriately in in vitro cell cultures. Immunisation of mice with the plasmid vectors elicited significant serum anti-BBG2Na IgG responses only in the mice receiving the plasmid encoding the secreted version of BBG2Na. Consistent with antibody induction data, sterilising lung protection against RSV-A challenge was also only observed in this group. These results indicate that the targeting of antigen expression (intracellular versus secreted) would be an important factor to consider in the design of nucleic acid vaccines.     

Global analysis of G-protein-coupled receptor signaling in human tissues

The G-protein-coupled receptor (GPCR) family mediates a host of cell–cell communications upon activation by diverse ligands. Numerous GPCRs have been shown to display anatomically selective patterns of gene expression, however, our understanding of the complexity of GPCR signaling within human tissues remains unclear. In an effort to characterize global patterns of GPCR signaling in the human body, microarray analysis was performed on a large panel of tissues to monitor the gene expression levels of the receptors as well as related signaling and regulatory molecules. Analysis of the data revealed complex signaling networks in many tissue types, with tissue-specific patterns of gene expression observed for the majority of the receptors and a number of components and regulators of GPCR signaling.     

Innate immune recognition of respiratory syncytial virus infection

Respiratory syncytial virus (RSV) is the leading cause of respiratory infection in infants and young children. Severe clinical manifestation of RSV infection is a bronchiolitis, which is common in infants under six months of age. Recently, RSV has been recognized as an important cause of respiratory infection in older populations with cardiovascular morbidity or immunocompromised patients. However, neither a vaccine nor an effective antiviral therapy is currently available. Moreover, the interaction between the host immune system and the RSV pathogen during an infection is not well understood. The innate immune system recognizes RSV through multiple mechanisms. The first innate immune RSV detectors are the pattern recognition receptors (PRRs), including toll-like receptors (TLRs), retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs), and nucleotide-biding oligomerization domain (NOD)-like receptors (NLRs). The following is a review of studies associated with various PRRs that are responsible for RSV virion recognition and subsequent induction of the antiviral immune response during RSV infection. [BMB Reports 2014; 47(4): 184-191]     

β-Sitosterol activates Fas signaling in human breast cancer cells

beta-Sitosterol is the most abundant phytosterol. Phytosterols are enriched in legumes, oil seeds and unrefined plant oils as found in foods such as peanut butter, pistachios and sunflower seeds. beta-Sitosterol inhibits the growth of several specific types of tumor cells in vitro and decreases the size and the extent of tumor metastases in vivo. The effects of beta-sitosterol on the extrinsic apoptotic programmed cell death pathway in human breast MCF-7 and MDA-MB-231 adenocarcinoma cells were examined, along with the extent of its incorporation into cellular membranes and its effects on cell growth, expression of Fas receptor pathway proteins, and caspase-8 activity. The results show that beta-sitosterol exposure promotes its enrichment in transformed cell membranes and significantly inhibits tumor cell growth. Concurrently, Fas levels and caspase-8 activity are significantly increased. These actions are specific, as expression of other proteins of the Fas receptor pathway, including Fas ligand, FADD, p-FADD and caspase-8, remain unchanged. These findings support the hypothesis that beta-sitosterol is an effective apoptosis-promoting agent and that incorporation of more phytosterols in the diet may serve a preventive measure for breast cancer.     

呼吸道合胞病毒F蛋白抗体的研究进展

呼吸道合胞病毒(respiratory syncytial virus,RSV)感染,是造成婴幼儿、学龄前儿童、免疫缺陷患者、老年人等高危群体住院治疗及死亡的重要病因。目前,多个预防RSV感染的候选疫苗正处于研发中,尚无安全、有效的疫苗面世。对RSV感染的处理仍以治疗为主,使用帕利珠单抗(Palivizumab)是当前仅有的预防药物。在过去数年间出现的新型抗体药物,如多克隆抗体、单克隆抗体、纳米抗体等有些已进入了临床前或I、II、III期临床试验阶段。融合蛋白(fusion protein,F蛋白)在RSV感染过程中是不可或缺的,它介导病毒包膜与宿主细胞膜的融合。在感染过程中,F蛋白从亚稳态的融合前构象状态(prefusion fusion protein,pre F)转变为热力学稳定的融合后状态(postfusion fusionprotein,post F)。近年来,研究人员通过不断筛选,获得了多株针对pre F的抗体。与结合post F的抗体相比,这些抗体具有更强的RSV中和活性。一些更新的抗体药物候选品,在实验中显示出了效力强、药代动力学特征明显、半衰期长等特点,并能以其他途径给药,而且能降低其制备成本。现就抗RSV pre F的抗体研究进展作一概述。