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1.
犬腺病毒是目前已知哺乳动物腺病毒属中致病性最强的一种,且世界分布范围较为广泛。犬腺病毒分为Ⅰ型和Ⅱ型,Ⅱ型可插入外源基因,诱导免疫反应、进行有效基因转移,其取代h Ad V-5载体,作为高效、安全载体被广泛用于基因治疗与疫苗。本文就犬腺病毒Ⅱ型的生物学特性、作为载体在基因治疗及疫苗的作用进行综述。  相似文献   

2.
<正>疫苗免疫是防控人类和动物疫病最经济有效的策略。以适宜的病毒、细菌等微生物或寄生虫为载体的活载体疫苗具有安全性高、能激发宿主多类型免疫应答、不需要佐剂等优势,是目前疫苗研究领域的热点之一。其中,以病毒为疫苗载体的研究最为广泛,技术也最为成熟,并且已有许多商品化的重组病毒载体疫苗。副流感病毒5型(Parainfluenza virus type 5,PIV5)为单负链RNA病毒,感染宿主范围广,单独感染一般不引起临床症状,致病性低。  相似文献   

3.
不分节段负股RNA病毒(nonsegmented negative—strand RNA viruses,NNSV)属于单负股病毒目,具有许多优良的特性,可以作为活病毒疫苗的候选载体,利用反向遗传学系统,表达外源基因,研发新型疫苗。NNSV载体疫苗的免疫原性,载体的容量,外源糖蛋白对载体病毒生物学的影响,以及插入基因的遗传稳定性等已成为当前活病毒疫苗载体研发的重要课题。  相似文献   

4.
猪流感病毒血凝素基因的研究进展   总被引:1,自引:1,他引:0  
猪流感是由猪流感病毒引起的一种急性、热性、高度接触传染性呼吸道疾病,可继发和并发多种细菌病和病毒病,已日益成为危害世界猪群的主要传染病之一。猪流感病毒血凝素基因作为流感病毒表面最主要的抗原基因,其表达蛋白具有丰富的生物学作用,对流感病毒的致病性起着主导作用。作者主要对猪流感病毒血凝素基因的研究进行了综述,为进一步防治猪流感及开发新型疫苗提供帮助。  相似文献   

5.
犬副流感病毒感染是由犬副流感病毒引起的,以急性呼吸道炎症为主的病毒性传染病。临床上以发热,流黏性鼻涕、打喷嚏、咳嗽等急性呼吸道症状为主要特征。本病主要发生于未经免疫或免疫措施不健全的犬。由于犬类疫苗的保护率较低,部分严格经过疫苗注射的犬也可发病。1病原副流感病毒。副流感病毒属副黏病毒科,副黏病毒属中的一个亚群,核酸型为单股RNA,病毒粒子呈多形性,一般为球状。本病毒对理化因素的抵抗力不强,在酸碱环境中易被破坏。一般的消毒药可将其杀死。犬副流感病毒主要通过呼吸道传染。病犬的鼻汁,气管、肺部分泌物中含有的大量…  相似文献   

6.
《中国兽医学报》2016,(8):1459-1463
负链RNA病毒的反向遗传学技术是一种新兴的分子生物学技术,作为负链RNA病毒的副流感病毒5型(parainfluenza virus 5,PIV5),是一种极具应用潜力的重组病毒活载体。现结合PIV5病毒载体特征,对其重组病毒的反向遗传学及其应用等做简要综述。  相似文献   

7.
为研究鸡传染性支气管炎病毒(IBV)作为载体表达外源基因的可行性,本研究以IBV疫苗株H120为病毒载体,在其非结构蛋白5a编码区上游插入鸡γ-干扰素(Ch IFN-γ)基因,通过反向遗传操作技术构建重组病毒。经RT-PCR和测序鉴定表明拯救获得重组病毒(r H120-c IFNγ/5a)。生物学特性研究结果表明,r H120-c IFNγ/5a感染鸡胚后能够引起特征性病变,但与其亲本病毒株H120相比,病毒的毒价及其在鸡胚中的复制能力有所下降。将r H120-c IFNγ/5a在鸡胚中连续传代,采用RT-PCR进行检测,结果表明Ch IFN-γ基因在病毒传至第9代时仍保持稳定,至第12代Ch IFN-γ基因出现部分或完全丢失现象。本研究结果为进一步研制以IBV为载体的新型基因重组疫苗奠定了基础。  相似文献   

8.
副流感病毒5型(Parainfl uenza virus 5,PIV5)为一类不分节段单股负链RNA病毒,可引起多种动物呼吸道感染,尤其可致犬病发"犬窝咳"。本文围绕PIV5病毒特征、基因组特征、编码蛋白、病毒的转录与复制以及PIV5相关疫苗的研究做一综述,旨在为PIV5疾病监测和PIV5相关疫苗研究提供科学依据。  相似文献   

9.
细胞受体是流感病毒感染、复制与传播的生物学基础.病毒血凝素基因的差异和细胞上不同类型的受体是影响病毒受体结合特性的两个重要因素.了解这两个因素有助于人们进一步认识流感的病原学、感染机制、流行病学等内容,对于流感的监测、疫苗研制和公共卫生学都将有借鉴意义.论文就流感病毒基因特点、细胞受体类型差异及二者相互作用的复杂性进行综述.  相似文献   

10.
牛病毒性腹泻病毒(bovine viral diarrhea virus, BVDV)引起牛发热、腹泻、黏膜糜烂溃疡等症状,给养牛业带来严重经济损失,新型疫苗的研发意义重大。狂犬病病毒(rabies virus, RV)作为病毒载体可稳定表达外源蛋白,反过来外源蛋白也不会阻碍病毒的复制。本研究目的是利用反向遗传操作技术构建和拯救表达BVDV结构蛋白的重组RV,以期获得一种能表达高水平BVDV E2蛋白的重组病毒。选择Ⅰ型BVDV主要优势抗原E2蛋白基因序列进行优化后合成E2基因片段,利用Overlap PCR的方法将E2基因改造为DE2片段,以RV疫苗毒株LBNSE为病毒载体,利用BsiWⅠ和NheⅠ酶切位点,将DE2基因插入LBNSE基因组中,成功构建pRV-DE2重组质粒。脂质体法将全长重组质粒转染BSR细胞后,拯救重组病毒RV-DE2,并用直接免疫荧光和RT-PCR的方法对其鉴定,对构建成功的病毒进行生长特性、致病性、重组蛋白表达特性等生物学特性和小鼠体内免疫效力的研究。结果表明,RV-DE2病毒滴度在F3代之后趋于稳定,在相同的培养条件下比亲本LBNSE病毒滴度高。重组病毒对小...  相似文献   

11.
The role of bovine respiratory syncytial virus, parainfluenza type 3 virus and bovine herpesvirus 1 as disease agents in 28 groups of young cattle on 19 dairy farms which raised their own replacements was investigated. Bovine respiratory syncytial virus infections occurred in 27, parainfluenza type 3 virus infections in all and bovine herpesvirus 1 infections in three of the 28 groups. Some infections were accompanied by clinical signs while others were entirely subclinical. Clinical respiratory disease was observed on 25 occasions in 20 of the groups. Respiratory disease was associated with a bovine respiratory syncytial virus infection on 15 occasions with parainfluenza type 3 virus infection in four cases and with bovine herpesvirus 1 infection in two cases. In four cases there was no association between the respiratory disease and any of the four virus infections. Bovine respiratory syncytial virus infections caused more serious respiratory problems than parainfluenza type 3 virus infections.  相似文献   

12.
Previous research has demonstrated that 4-ipomeanol toxicosis can enhance the severity of para-influenza virus-induced pneumonia in mice. The objectives of this study were to determine whether calves are susceptible to 4-ipomeanol-induced enhancement of parainfluenza type 3 viral pneumonia and to determine whether 4-ipomeanol alters pulmonary replication of parainfluenza virus. Male Holstein calves were injected with either 4-ipomeanol (3 mg/kg) or vehicle (polyethylene glycol) 3 days prior to intratracheal inoculation with either parainfluenza virus or sham inoculum of culture medium. Calves in the four treatment groups (ipomeanol-parainfluenza, ipomeanol-medium, vehicle-parainfluenza, and vehicle-medium) were necropsied at 5 days after inoculation with parainfluenza virus or medium. The lungs were studied by correlated methods of light and electron microscopy, digitizing morphometry and pulmonary lavage to quantitate the severity of pneumonia. Pulmonary viral titers were determined, and viral antigen was identified in the lung by immunoperoxidase technique. The calves in the ipomeanol-virus treatment group had over a 9-fold higher (P less than 0.05) volume density of virus-induced interstitial pneumonia than did the calves in the other three treatment groups. This 4-ipomeanol-enhanced viral pneumonia was associated with significantly greater (P less than 0.05) numbers of pulmonary macrophages and neutrophils in the lavage fluid and higher (P less than 0.05) pulmonary titers of pulmonary infectious parainfluenza virus. Four-ipomeanol-enhanced viral pneumonia was characterized in part by extensive hyperplasia of type II alveolar epithelial cells and by dense aggregates of macrophages and neutrophils in alveolar spaces and interalveolar septa. The results indicate that 4-ipomeanol exacerbates interstitial pneumonia in calves induced by bovine parainfluenza type 3 virus.  相似文献   

13.
Ewes (N = 7) and their lambs (N = 12) were vaccinated with a commercial modified live infectious bovine rhinotracheitis-parainfluenza type 3 virus vaccine. Both the vaccinated ewes and lambs and a group of unvaccinated ewes (N = 8) and their lambs (N = 13) were subsequently challenged with virulent parainfluenza type 3 virus. Although absolute immunity to infection and clinical response was not conferred, the clinical response was less severe in vaccinated lambs. Vaccinated animals also shed parainfluenza type 3 virus in nasal secretions for a shorter time than nonvaccinated animals. Some vaccinated lambs developed a persistent infectious bovine rhinotracheitis virus infection that was recrudesced by treatment with dexamethasone. It was concluded that vaccination was of benefit in reducing the severity of infection with parainfluenza type 3 virus. However, the inclusion of infectious bovine rhinotracheitis virus in a vaccine for sheep respiratory tract disease is highly questionable as it might increase the risk factor associated with vaccination. The consequences of the persistence of infectious bovine rhinotracheitis virus are now known.  相似文献   

14.
Accurate identification of bovine parainfluenza type 3 virus in bovine respiratory disease requires dependable, sensitive, and specific techniques for detection in affected animals. Immunohistochemical testing can be a rapid and reliable means of demonstration of virus in tissues from suspect cases; however, this procedure is dependent upon the quality of the antisera directed against the viral antigens. The production of rabbit polyclonal and murine monoclonal antibodies directed against bovine parainfluenza type 3 virus and techniques for their use in fresh-frozen and formalin-fixed paraffin-embedded tissues in immunofluorescence and immunoperoxidase-based immunohistochemical tests are described.  相似文献   

15.
Two hundred serum samples from Texel and Texel crossbred sheep (non-indigenous breeds) and 200 from indigenous Northern Ireland breeds (mainly Blackface, Cheviot and Border Leicester crosses) were tested for antibodies to parainfluenza virus types 1, 2 and 3, respiratory syncytial virus, bovine adenovirus (subgroups 1 and 2), influenza type A, maedi-visna virus and bovine virus diarrhoea virus. The percentage of animals with antibodies to parainfluenza virus 3 (50 to 56 per cent) and adenovirus subgroups 1 and 2 (70 to 90 per cent) was comparable in both groups. Infection of sheep with subgroup 2 adenoviruses has not previously been reported. In the case of respiratory syncytial virus and bovine virus diarrhoea virus, the percentage of animals positive was higher in the non-indigenous group (55.5 and 53 per cent, respectively) than in indigenous breeds (18.5 and 11 per cent, respectively). No antibodies were detected to parainfluenza virus 1 or 2, influenza A or maedivisna virus.  相似文献   

16.
Three canine parainfluenza viruses type 5 (CPIV-5) were isolated from lung tissues of 3 Korean dogs with mild pneumonia between 2008 and 2009. The isolates were fully sequenced and compared with published reference sequences. The size of the genome was 15 246 nucleotides long and no remarkable differences were found when compared with previously published reference sequences. In phylogenetic analysis based on the F and P genes, parainfluenza virus 5 (PIV-5) strains were divided into at least 3 subgroups. Three CPIV-5 strains were clustered with CPIV-5 T1, H22 and 78524 strains. All PIV-5 strains were independent of the host species, geographical distribution, and the isolated period.  相似文献   

17.
A new transtracheal bronchoalveolar lavage technique for the diagnosis of respiratory disease in sheep under field conditions was tested in 76 sheep. The sheep were divided into three groups, normal sheep, sheep with clinical signs of respiratory disease and housed sheep, on the basis of their respiratory disease history and husbandry conditions. The detection of Mannheimia haemolytica and Mycoplasma ovipneumoniae or parainfluenza virus type 3 and bovine respiratory syncytial virus antigen in the lavage samples was closely correlated with clinical disease. The sheep with clinical respiratory disease had a higher mean percentage of neutrophils in the lavage fluid than the sheep in the other two groups.  相似文献   

18.
Biologically speaking, Sendai virus (SeV), the murine parainfluenza virus type 1, is perceived as a common respiratory pathogen that is endemic in many rodent colonies throughout the world. Currently it is believed that SeV is the leading cause of pneumonia in mice and together with the mouse hepatitis viruses, is the most prevalent and important of the naturally occurring infections of mice. The scientific community also considers SeV as the archetype organism of the Paramyxoviridae family because most of the basic biochemical, molecular and biologic properties of the whole family were derived from its own characteristics. Recently, scientific interest for this old pathogen has re-emerged, this time because of its potential value as a vector for gene transfer. This review aimed at drawing an exhaustive picture of this multifaceted pathogen.  相似文献   

19.
牛副流感病毒3型RT—PCR检测方法的建立   总被引:2,自引:0,他引:2  
参照GenBank中公布的牛副流感病毒3型(Bovineparainfluenzavirus3,BPIV-3)全基因序列,针对BPIV-3特异性NP蛋白保守基因设计一对引物,建立了BPIV-3的RT—PCR诊断方法。其最佳扩增退火温度为58.1℃,引物浓度为1.0μmol/L。采用该方法扩增BPIV-3参考病毒.能扩增出425bp预期大小的特异性片段,而扩增牛病毒性腹泻/黏膜病病毒、牛传染性鼻气管炎病毒、牛合胞体病毒、猪瘟病毒以及牛支原体、大肠埃希氏菌、牛巴氏杆菌和沙门氏菌等常见病毒和细菌均呈阴性结果。对参考病毒进行梯度稀释检测,结果证明该法检测BPIV-3的灵敏度可达10^-3FCID50/0.1mL。  相似文献   

20.
动物狂犬病流行毒株的抗原性差异分析   总被引:1,自引:0,他引:1  
利用9株抗狂犬病病毒(Rabies virus,RABV)核蛋白单克隆抗体,通过间接免疫荧光方法对分离的34株传至F6代N2A细胞适应株进行了抗原差异分析。结果表明:这些RABV分离株存在抗原差异,根据病毒与单抗反应的类型,将所分析的病毒株分为6个抗原变异型。根据N基因系统发生分析将所分析的病毒株分为4个进化群,结果表明不同进化群病毒间的遗传差异与抗原分型没有直接的联系。  相似文献   

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