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以纯化的猪传染性胃肠炎病毒重组M蛋白免疫BALB/c小鼠,按常规方法进行融合、筛选,最终获得3株抗TGEVM蛋白的杂交瘤细胞系1B3、3C2、4A5,染色体平均记数为89对、92对、90对,间接ELISA检测1B3、3C2、4A5细胞培养上清的效价分别为1/4000、1/1000、1/4000,腹水效价分别为2×10~4、2×10~5、2×10~5。通过间接ELISA做病原检测,这3株单抗不与猪流行性腹泻病毒、猪伪狂犬病病毒和猪轮状病毒发生交叉反应,而与传染性胃肠炎病毒显示良好的特异性。用制备的单抗通过间接免疫荧光做病原检测,发现染色后TGEV感染的细胞培养物在胞浆和细胞膜上出现黄绿色荧光,未接种病毒的细胞培养物未见有黄绿色闪亮荧光,结果表明,所制备的抗重组TGEVM蛋白的单抗对病原检测具有很高的特异性,为TGEV准确快速的病原诊断和TGEV感染相关的基础性研究提供了物质基础。 相似文献
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猪流行性腹泻病毒（porcine epidemic diarrhea virus,PEDV）是一种全球分布的α冠状病毒,能引起仔猪流行性腹泻,猪流行性腹泻一旦暴发会给养殖业带来巨大的经济损失。在病毒感染期间,Ⅰ型干扰素（type Ⅰ interferon,IFN-Ⅰ）是先天性抗病毒反应的关键介质。大多数冠状病毒通过限制IFN的产生和IFN应答的激活而产生一些策略以规避IFN应答。然而,PEDV颉颃IFN抗病毒作用的分子机制尚未完全清楚。猪感染PEDV后,机体的先天免疫不能有效抵抗PEDV的侵害,PEDV通过限制或阻断IFN的功能和隐藏自身的病原体相关分子模式（pathogen-associated molecular patterns,PAMP）两种途径逃逸宿主先天免疫。在此过程中,PEDV的结构蛋白和非结构蛋白及一些蛋白酶起到了关键作用,核衣壳（nucleocapsid,N）蛋白能抑制IFN-Ⅰ的产生,协助病毒逃避机体的抗病毒天然免疫,木瓜样蛋白酶通过去泛素化酶活性阻断天然免疫信号通路,PEDV也可通过阻断双链核糖核酸（double-stranded RNA,dsRNA）诱导IFN-Ⅰ的产生,以逃避宿主的先天免疫。这些研究为深入了解IFN在PEDV致病过程中的作用及PEDV逃避IFN抗病毒的机制提供了理论依据,并有助于深入了解病毒与宿主先天性免疫之间的关系,同时也为PEDV的防治及PEDV疫苗的研发提供参考。 相似文献
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视黄酸诱导基因Ⅰ(RIG-Ⅰ)为RLRs受体家族的成员,是比较关键的细胞质内病原体识别受体,可识别细胞内的单链、双链等RNA病毒成分,被激活的RIG-Ⅰ受体及其CARD在TRIM25的作用下连接泛素链使其寡聚化,通过与线粒体抗病毒信号蛋白(MAVS)相互作用,激活MAVS及下游转录因子IRF3和NF-κB,从而诱导Ⅰ型干扰素和炎性因子的表达,最终介导宿主的抗病毒免疫应答。鉴于RIG-Ⅰ持续激活可导致炎性因子对自身细胞的损伤,因此RIG-Ⅰ样受体信号通路受到宿主严格的调控。而某些病毒为逃避宿主细胞的免疫应答,进化出多种机制靶向调节RIG-Ⅰ及MAVS,从而阻断信号通路。论文从RIG-Ⅰ识别病毒机制、激活下游信号传导、宿主细胞对信号传导途径的调控以及病毒逃避机制等方面重点阐述RIG-Ⅰ所介导的天然免疫反应。 相似文献
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Development of a simple IgE‐independent anaphylactic model using buckwheat antigen and B‐type CpG oligodeoxynucleotide from Streptococcus thermophilus 
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下载免费PDF全文 Shireen Nigar Kazushi Oshiro Yeqin Wang Takashi Sato Takeshi Shimosato 《Animal Science Journal》2016,87(5):710-717
We developed a severe anaphylactic model in mice using buckwheat antigen and B‐type CpG‐oligodeoxynucleotides (CpG‐ODNs) from Streptococcus thermophilus genome. In typical systemic anaphylaxis models, animals are challenged with large quantity of antigens via an intravenous (i.v.) route. Here, we showed a simple anaphylactic shock after challenge via intraperitoneal (i.p.) route. The i.p. method is simpler than i.v. administration and has a lower risk for failure. To generate this anaphylactic model, 5‐week‐old female BALB/c mice were first i.p. sensitized with buckwheat antigen mixed with B‐type CpG‐ODN. After 2 weeks, mice were challenged with antigen to induce anaphylactic shock, which was evaluated by scoring the severity symptoms and measuring serum levels of various proteins and splenic cell producing cytokines. Immunoglobulin (Ig)G2a production and interferon‐γ positive cells were markedly increased in mice immunized with antigen mixed with B‐type CpG‐ODN, whereas serum IgE levels were decreased by B‐type CpG‐ODN. We also examined the effects of various ODNs (A, B and C‐type CpG‐ODNs) and antigens (buckwheat, α‐casein, β‐lactoglobulin and ovalbumin) on anaphylactic severity, and found that the combination of buckwheat and B‐type CpG‐ODN induced the most intense anaphylactic shock. This model is expected to contribute to the study of the prevention of anaphylactic shock. 相似文献
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Li-feng Huang Yong-ming Yao Jin-feng Li Shu-wen Zhang Wen-xiong Li Ning Dong Yan Yu Zhi-yong Sheng 《Fitoterapia》2012
High mobility group box 1 protein (HMGB1), a potent pro-inflammatory cytokine, contributes to the pathogenesis of diverse inflammatory and infectious disorders. Some studies have illustrated the potential effect of HMGB1 on regulatory T cells (Tregs). Astragaloside IV (AST IV) isolated from a Chinese herb, Astragalus mongholicus, is known to have a variety of immunomodulatory activities. However, it is not yet clear whether AST IV possesses potential regulatory effect on the pro-inflammatory ability of HMGB1 with subsequent activation of Tregs. This study was carried out to investigate the antagonistic effects of different doses of AST IV on the immune function of Tregs mediated by HMGB1 in vitro. Tregs isolated from the spleens of mice were co-cultured with HMGB1 and/or AST IV. Cell phenotypes of Tregs were analyzed, and the contents of various cytokines in the cell supernatants as a result of co-culture and the proliferation of CD4+CD25− T cells were determined. Results showed that HMGB1 stimulation resulted in significantly down-regulation of expressions of Tregs cell phenotypes. However, AST IV can rival the suppressing effect of HMGB1 on immune function of Tregs with a dose-dependent in vitro. These results indicate that AST IV has the potential therapeutic action on inflammation augmented by HMGB1. 相似文献
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感染鸡贫血病毒雏鸡接种新城疫疫苗后免疫功能和免疫调节的变化 总被引：1，自引：1，他引：0
雏鸡1日龄感染鸡贫血病毒，8日龄接种Lasota疫苗，以未感染免疫雏鸡为对照，于免疫后7、14、28d检测血清免疫球蛋白IgG、IgM、IgA,在凝抑制抗体（HI）滴度；胸腺、法氏囊、脾脏T细胞、IgG^ 、IgM^ 、IgA^ ,抗体生成细胞数量及T、B细胞增殖反应；胸腺、脾脏细胞因子IL－2、IFN活性的变化。结果发现，感染CAV雏鸡Lasota疫苗免疫后，其血清IgG、IgM、IgA免疫球蛋白含量明显减少，HI抗体滴度降低；胸腺、法氏囊、脾脏T细胞、抗体生成细胞数量降低及T、B细胞增殖反应减弱，胸腺、脾脏IL－2及TNF诱生活性降低，表明其细胞免疫和体流免疫功能以及细胞因子免疫调节作用均未感染免疫雏鸡明显减弱。 相似文献
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Viral Haemorrhagic Septicaemia Virus (VHSV) isolates virulent to marine fish species can replicate in freshwater species, although producing little or no mortality. Conversely, isolates from freshwater fish do not cause disease in marine species. An inverse relationship between VHSV virulence and host mx gene up-regulation has been described for several fish species, suggesting that differences between the antagonistic activity exerted by these isolates might be involved in the outcome of infections. In this study, the antagonistic activity against the type I interferon system of two representative marine and freshwater VHSV isolates has been characterised using RTG-2 cells stably transfected with the luciferase gene under the control of the Senegalese sole mx (ssmx) promoter, RTG pssmx-luc cells. Both isolates exerted a dose-dependent negative effect on the activation of ssmx promoter, showing a notably different minimal viral dose to exert the antagonism. In particular, an inverse relationship between the minimal MOI required and the viral virulence to sole has been recorded, which suggests this parameter as a possible in vivo VHSV virulence marker. Furthermore, the quantification of the endogenous inf I, mx1 and mx3 mRNA has demonstrated differences between both isolates in their antagonistic activity. Besides, a different nv RNA kinetics, which seems to depend on specific cellular factors, has been recorded for both isolates. This knowledge could contribute to the development of efficient tools to fight against viral infections in fish farming. For that purpose, the RTG pssmx-luc cells may be a suitable in vitro tool to identify the molecular mechanisms underlying VHSV-host interactions. 相似文献
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鸡贫血因子病的免疫病理学变化 总被引：6，自引：2，他引：6
用鸡贫血病毒（CAV）感染1日龄健康AA雏鸡，以未感染同龄雏鸡为对照，在感染后7、14、21、28、35、42和49d检测其免疫器官与体重比值，胸腺、脾脏T细胞白细胞介素2（IL-2）和干扰素（IFN）诱生活性，胸腺、法氏囊、脾脏T、B细胞增殖反应，胸腺、法氏囊、脾脏、盲肠扁桃体及哈德尔腺中α-萘酚酯酶阳性[ANAE#+（+）]T细胞、IgG、IgM、IgA抗体生成细胞数量，外周血液中T、B细胞数量，血清、泪液、气管液、肠液、胆汁中IgG、IgM、IgA含量的动态变化。揭示了感染鸡细胞因子IL-2、IFN的免疫调节发生障碍、中枢与外周免疫器官的细胞免疫和体液免疫功能呈现抑制，呼吸道与消化道的局部免疫防御功能降低。 相似文献
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鹅γ-干扰素成熟蛋白的表达及其生物学活性研究 总被引：6，自引：0，他引：6
【目的】检测重组鹅IFN-γ的生物学活性。【方法】将鹅IFN-γ成熟蛋白基因分别克隆到原核表达载体pET30a，杆状病毒转移载体pMelBacA和pBlueBacHis2A。对鹅IFN-γ成熟蛋白进行原核和真核表达系统表达；利用体外活性试验检测表达产物的生物学活性。【结果】原核和真核表达系统表达了重组鹅IFN-γ成熟蛋白，并制备其原核表达产物的多克隆抗体；重组鹅成熟IFN-γ可以诱导鹅巨噬细胞产生NO，并能抑制GPMV在鹅胚成纤维细胞中的增殖。【结论】重组鹅成熟IFN-γ具有鹅巨噬细胞激活活性和抗病毒活性。 相似文献