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猪圆环病毒2型免疫学研究进展 总被引：1，自引：0，他引：1
猪圆环病毒2型(PCV2)感染猪体后,可引发猪体内相应的细胞免疫反应和体液免疫反应,同时可造成免疫系统损伤,其中包括CD4+/CD8+/MHC II T细胞和B细胞显著减少,相关细胞因子γ-干扰素、IL-a和IL-10增加,产生病毒中和抗体等。人们已鉴定了PCV2衣壳蛋白的多个B/T细胞抗原表位,其中包括PCV2特异的氨基酸残基231～233和195～202和PCV1和PCV2共有的氨基酸残基156～162和175～192位;T细胞抗原表位包括Rep蛋白的第81～100位和201～220位氨基酸和ORF3蛋白的第31～50位氨基酸。在PCV2疫苗研究中,灭活疫苗和亚单位疫苗成为现时养猪生产中的常用疫苗、病毒活载体疫苗和DNA疫苗也成为疫苗研究的热点。 相似文献
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猪圆环病毒2型(PCV2)感染后会导致断奶仔猪多系统衰竭综合征(PMWS)等"猪圆环病毒相关疾病"(PCVADs),给全球养猪业造成了巨大的经济损失。疫苗免疫是防控该病的有效手段,近年来市场上推出了PCV2灭活疫苗、嵌合疫苗和亚单位疫苗。PCV2变异较快,主要临床流行毒株从PCV2b逐渐演变为PCV2d,现有商业化疫苗免疫效果需进一步研究证实。论文就近年来国内外PCV2传统疫苗、新型基因工程疫苗、PCV2疫苗与其他疫苗联合免疫的研究进展进行综述,旨在为猪圆环病毒相关疾病的防控及疫苗的开发与利用提供参考。 相似文献
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猪圆环病毒相关疾病(PCVAD)的发生依赖猪圆环病毒2型(PCV2)的感染,表现为一群复杂的多因子综合征。目前在野外流行的PCV2被分为PCV2a和PCV2b两个亚群。北美和其它国家PCVAD的暴发通常与主要基因型从PCV2a转变为PCV2b有关。因此,有人提出基因型存在致病性和抗原性差异。总体来说,毒力是特定PCV2分离株的特性,与基因型无关。此外,报道证实只有少数抗原差异。就免疫病理学而言,位于衣壳蛋白C端一个保守的诱骗表位为不能鉴定基因型之间的致病力差异提供了解释。最后本文讨论了PCV2的遗传变异对疫苗和诊断方法的影响。 相似文献
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猪圆环病毒2型(PCV2@@)是引起断奶仔猪多系统衰竭综合征(PMWS)、猪皮炎与肾病综合征(PDNS)和猪呼吸道疾病综合征(PRDC)等多种疾病的主要病原,并在猪群中广泛存在,给世界养猪业造成了巨大的经济损失.疫苗预防是当前PCV2防制的主要举措之一.目前PCV2商品化疫苗主要包括灭活疫苗和亚单位疫苗,临床应用结果表明,这些疫苗确实获得一定的免疫保护效果,并在有效防控PCV2感染中发挥了重要作用.PCV2传统疫苗也存在一定的局限性,抗原含量偏低、成本偏高、无法有效诱导细胞免疫等,因此研制更安全、高效、廉价的新型基因工程疫苗是未来发展的趋势.文章就PCV2商品化疫苗的应用效果和新型疫苗的研究成果进行了详细阐述,以期为PCV2的防控提供参考. 相似文献
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猪圆环病毒2型疫苗的研究进展 总被引：1，自引：0，他引：1
猪圆环病毒2型(PCV2)是引起断奶仔猪多系统衰竭综合征(PMWS)的主要病原,给全球养猪业造成了巨大经济损失.PCV2感染可以破坏动物机体的免疫系统,造成严重的免疫抑制,容易诱发多种细菌及病毒的混合感染与继发感染,给疾病的诊断和治疗带来巨大的困难.疫苗免疫接种是防控PCV2感染的有效手段,有关PCV2疫苗的研究已成为国内外学者的关注热点.迄今为止,欧美几家跨国公司已先后推出商品化的PCV2灭活疫苗、亚单位疫苗及嵌合病毒疫苗,国内也已研制出PCV2灭活疫苗,这些疫苗的推广应用为有效防控猪圆环病毒病发挥了重要作用.鉴于这些疫苗尚不能完全阻断PCV2传播,无法彻底清除体内感染的病毒,因此,开发高效、价廉的新型活载体疫苗、核酸疫苗及标记疫苗是今后研究的趋势.笔者在本文中概括地介绍了目前商品化的PCV2疫苗的特性和免疫效力,并对近年来有关PCV2活载体疫苗、核酸疫苗及标记疫苗等新型疫苗的研究进展进行综述,以期为猪圆环病毒病的防制提供参考. 相似文献
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猪圆环病毒Ⅱ型(PCV2)是猪圆环病毒相关疾病(PCVAD)的病原。猪圆环病毒相关疾病(PCVAD)也叫做断奶仔猪多系统衰竭综合征(PMWS)。开发有效的猪圆环病毒Ⅱ型(PCV2)疫苗是控 相似文献
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猪圆环病毒2型分子流行病学及疫苗研究进展 总被引：2，自引：0，他引：2
猪圆环病毒2型(PCV2)在世界范围内广泛分布,主要以PCV2a和PCV2b两种基因型为主,PCV2b亚型为当前流行基因型。现有商品化疫苗主要针对PCV2a型病毒,也可对PCV2b型病毒产生部分交叉保护,但不能显著控制PCV2b型病毒在猪群中的传播。除此之外,由于已有的商品化疫苗以传统疫苗为主,存在种毒增殖难、疫苗生产周期长等缺点。因此,研发PCV2b新型疫苗可能成为未来PCV2疫苗研制的主要方向。对PCV2的分子流行病学及疫苗研究现状进行了综述,以期为PCV2疫苗的研究提供参考。 相似文献
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Shang SB Li YF Guo JQ Wang ZT Chen QX Shen HG Zhou JY 《Research in veterinary science》2008,84(1):150-157
Porcine circovirus type 2 (PCV2) has been recently associated with a number of disease syndromes, especially postweaning multisystemic wasting disease (PMWS). Herein, an alternative indirect enzyme-linked immunosorbent assay (ELISA) for detection of PCV2 antibody was developed using nuclear localization signal-truncated capsid protein of PCV2 produced in Escherichia coli (CAP ELISA). This assay was validated by comparison with an indirect immunofluorescence assay (IIF) and a PCV2-based ELISA. The diagnostic sensitivity (DSN), specificity (DSP) and accuracy of the CAP ELISA were 95.3%, 93.9% and 95.1%, compared with IIF on 1080 field serum samples, and 93.3%, 84.2% and 91.1%, compared with the PCV2-based ELISA on 79 field sera, respectively. Cross-reactivity assay showed that this assay was PCV2-specific. Repeatability tests revealed that the coefficients of variation of positive sera within and between runs were less than 15%. This ELISA is simpler to produce and perform, time-saving and suitable for large scale surveys of PCV2 infection at low cost and the evaluation of the efficiency of various vaccines against PCV2. 相似文献
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Quintana J Segalés J Calsamiglia M Domingo M 《Veterinary journal (London, England : 1997)》2006,171(3):570-573
The absence of extraneous viruses is a requirement in the quality control of vaccines for veterinary use in the European Pharmacopoeia. A polymerase chain reaction (PCR) assay for the detection of porcine circovirus type 1 (PCV1) and type 2 (PCV2) was evaluated in 18 commercial porcine vaccines. Since vaccine components may contain PCR enhancers or inhibitors, 13 of the studied vaccines (used as diluents) were subsequently spiked with different dilutions of PCV2 and tested by PCR. Although PCV2 DNA was not detected in any of the vaccines tested, PCV1 was detected in 2/18 vaccines (11%). Eleven out of 13 PCV2 spiked vaccines showed a positive PCR result. The lack of amplification observed in two spiked vaccines suggested that use of the PCR assay to detect PCV2 could depend on vaccine composition. The results of this exploratory study have demonstrated that PCR is a rapid and fairly sensitive method for the detection of porcine circoviruses as extraneous agents in vaccine products and can be used in the quality control of pig vaccines. The study has also indicated the need for optimising the sensitivity of PCR methods for PCV genome detection in vaccine products. 相似文献
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猪圆环病毒2型(PCV2)是引起断奶仔猪多系统衰竭综合征的主要病原,疫苗免疫是防控PCV2的重要手段之一。文章从专利角度对PCV2疫苗的研究现状进行了综述,对涉及PCV2疫苗的专利申请概况、专利分布、重要申请人以及重点专利进行了分析,旨在为PCV2疫苗的开发和专利申请提供参考。 相似文献
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猪圆环病毒2a/2b亚型病毒株灭活疫苗及其重组Cap蛋白亚单位疫苗的交互免疫实验 总被引：3，自引：0，他引：3
为评价猪圆环病毒(PCV)2a/2b两种基因型病毒株及其重组Cap蛋白(rCap)之间的交互免疫,本研究采用PCV2a-LG株和PCV2b-YJ株制备了2种病毒灭活疫苗,及其重组杆状病毒表达的2种Cap蛋白(PCV2a-rCap和PCV2b-rCap)亚单位疫苗.选用8周龄BALB/c鼠165只,随机分成11组,每组15只,用上述4种疫苗各免疫2组,以PCV2a或PCV2b株攻毒.攻毒后,所有鼠均未见肉眼可见的临床症状和病理变化.采用IPMA法检测抗体,4种疫苗于免疫第3周抗体转阳,第5周抗体效价达到1:200～1:800倍,其中PCV2a-rCap免疫组抗体效价最高.2种灭活苗和PCV2a-rCap免疫组攻击同型或异型病毒株均可以获得完全保护.以PCV2a和PCV2b各为指示病毒对病毒抗血清和rCap蛋白抗血清进行交叉中和试验,同型病毒株与同型血清的中和抗体效价均高于异型病毒株.病理观察显示,免疫鼠均未见明显病理变化,攻毒对照鼠肺脏出现一定程度的病理损伤.本研究表明,病毒灭活疫苗及其rCap亚单位疫苗PCV2a和PCV2b可提供交叉保护. 相似文献
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猪圆环病毒Ⅱ型广东分离株全基因组的克隆和序列分析 总被引：1，自引：0，他引：1
分离了9株猪圆环病毒Ⅱ型（PCV2）广东地方分离株，并进行了全基因组序列测定；对这9株PCV2广东分离毒株的ORF1和ORF2基因的序列分析表明ORF2的变异程度要比ORF1的变异程度大；对PCV2衣壳蛋白的氨基酸序列同源性比较发现了PCV2毒株间存在1个氨基酸变异程度较大的区域和2个氨基酸变异程度较小的区域，其中前两个区域与两个主要的免疫反应区域相对应；将这9个毒株的全基因组序列与GenBank上收录的18个PCV2毒株的全基因组序列基因进化树分析表明，这9个PCV2广东分离株彼此之间及与国内PCV2分离株、欧洲株之间更接近，而与韩国、中国台湾、日本和美洲毒株之间则稍远，因而在选PCV2疫苗免疫时，建议尽量使用国内生产的疫苗或自制组织灭活疫苗进行免疫。 相似文献
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为了解四川地区规模化猪场所用蓝耳病和猪瘟疫苗中BVDV和PCV的污染情况,笔者选取了几种市售蓝耳病疫苗和猪瘟疫苗进行PCR检测。检测结果为：10份猪瘟活疫苗样品和9份蓝耳病活疫苗样品中,BVDV污染率为10．53％;PCV2污染率也为10．53％,所有样品中未检出PCVl。 相似文献
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The objective of this study was to evaluate the effect of porcine circovirus type 2 (PCV2) vaccines on PCV2-viremic and -seropositive piglets born from naturally PCV2-infected sows against postnatal PCV2 challenge. The experimental design was aimed at mimicking commercial swine rearing conditions to evaluate the response of the PCV2 vaccine on PCV2-viremic and -seropositive piglets after experimental PCV2 challenge. PCV2a (or 2b)-viremic piglets received a PCV2 vaccine at 21 days of age followed by a PCV2b (or 2a) challenge at 49 days of age (28 days post vaccination). The PCV2 vaccines elicited a high level of humoral (as measured by immunoperoxidase monolayer assay and neutralizing antibody titers) and cellular (as measured by the frequency of PCV2-specific interferon-γ-secreting cells) immune response in the PCV2-viremic piglets after vaccination even in the presence of maternally derived antibodies (MDA). The initial infection of PCV2 in the pigs was not affected by PCV2 vaccination, however the challenging PCV2 was reduced by PCV2 vaccination on PCV2-viremic pigs. The results from this study demonstrate that the PCV2 vaccine used in this study is effective at reducing PCV2 viremia and lymphoid PCV2 DNA, even for PCV2-viremic pigs with passively acquired MDA at the time of vaccination. 相似文献
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Allan GM Caprioli A McNair I Lagan-Tregaskis P Ellis J Krakowka S McKillen J Ostanello F McNeilly F 《Zoonoses and public health》2007,54(5):214-222
Porcine circovirus type 2 (PCV2) infection is now recognized as the major factor in the development of post-weaning multisystemic wasting syndrome (PMWS). Although Koch's postulates have been fulfilled for PCV2 and PMWS, the severe clinical expression of the disease observed in field cases has been difficult to reproduce experimentally. Some studies have demonstrated that immune stimulation associated with the use of some commercially available swine vaccines may trigger progression of PCV2 infection to disease and lesions characteristic of PMWS. Here we describe the effects on PCV2 infection in an experimental model following the use of a commercially available modified live vaccine to porcine respiratory and reproductive syndrome virus (PRRSV). Although none of the piglets infected with PCV2 developed clinical PMWS, the severity of microscopical lesions and the PCV2 antigen load associated with these lesions were higher in the PRRSV-vaccinated piglets compared with those detected in the PCV2 only infected animals. 相似文献