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1.
Vesicular stomatitis virus (VSV) causes a contagious disease of horses, cattle, and pigs. When DNA copies of messenger RNA's for the G or N proteins of VSV were linked to a vaccinia virus promoter and inserted into the vaccinia genome, the recombinants retained infectivity and synthesized VSV polypeptides. After intradermal vaccination with live recombinant virus expressing the G protein, mice produced VSV-neutralizing antibodies and were protected against lethal encephalitis upon intravenous challenge with VSV. In cattle, the degree of protection against intradermalingually injected VSV was correlated with the level of neutralizing antibody produced following vaccination.  相似文献   

2.
Two avirulent herpes simplex viruses generate lethal recombinants in vivo   总被引:13,自引:0,他引:13  
While it is widely appreciated that infection with a virulent virus can produce disease in an animal, the ability of a mixture of avirulent viruses to produce disease by means of complementation or recombination in vivo has not been established. In this study, two weakly neuroinvasive herpes simplex virus type 1 (HSV-1) strains were simultaneously inoculated onto the footpads of mice. Many (62%) of the animals that received a 1:1 mixture of the viruses died, whereas the animals that received a similar or 100-fold higher dose of each agent alone survived. Of fourteen viruses isolated from the brains of ten mice that died after receiving the mixture of the two weakly neuroinvasive viruses, eleven were recombinants; three of these recombinants were lethal when reapplied to the footpads of mice. These results show that two avirulent HSV-1 variants may interact in vivo to produce virulent recombinants and a lethal infection. They also suggest that different genetic lesions account for the weakly neuroinvasive character of the HSV-1 strains ANG and KOS after footpad inoculation.  相似文献   

3.
In humans, herpes simplex virus causes a primary infection and then often a latent ganglionic infection that persists for life. Because these latent infections can recur periodically, vaccines are needed that can protect against both primary and latent herpes simplex infections. Infectious vaccinia virus recombinants that contain the herpes simplex virus type 1 (HSV-1) glycoprotein D gene under control of defined early or late vaccinia virus promoters were constructed. Tissue culture cells infected with these recombinant viruses synthesized a glycosylated protein that had the same mass (60,000 daltons) as the glycoprotein D produced by HSV-1. Immunization of mice with one of these recombinant viruses by intradermal, subcutaneous, or intraperitoneal routes resulted in the production of antibodies that neutralized HSV-1 and protected the mice against subsequent lethal challenge with HSV-1 or HSV-2. Immunization with the recombinant virus also protected the majority of the mice against the development of a latent HSV-1 infection of the trigeminal ganglia. This is the first demonstration that a genetically engineered vaccine can prevent the development of latency.  相似文献   

4.
The gene coding for the circumsporozoite antigen of the malaria parasite Plasmodium knowlesi was inserted into the vaccinia virus genome under the control of a defined vaccinia virus promoter. Cells infected with the recombinant virus synthesized polypeptides of 53,000 to 56,000 daltons that reacted with monoclonal antibody against the repeating epitope of the malaria protein. Furthermore, rabbits vaccinated with the recombinant virus produced antibodies that bound specifically to sporozoites. These data provide evidence for expression of a cloned malaria gene in mammalian cells and illustrate the potential of vaccinia virus recombinants as live malaria vaccines.  相似文献   

5.
以RT-PCR扩增新城疫病毒Mukteswar株F基因F1片段和F2片段,以核酸内切酶Kpn I和Xba I对目的基因片段及质粒pCAPZαA进行酶切,连接酶切产物,转化E. coli DH5α.以PCR方法确定Mukteswar F1和Mukteswax F2的阳性重组子均为4个.对阳性重组子进行酶切鉴定及序列分析,结果,重组质粒pGAPZαA-F1、pGAPZαA-F2及质粒pGAPZαA的酶切电泳条带与试验设计大小相符;基因测序得到的重组子中F1和F2序列长度分别为1 198 bp、269 bp,与新城疫病毒Mukteswar株F基因序列比对,其序列长度和核苷酸排列完全一致.结果表明重组质粒中目的基因片段的核苷酸序列、大小和插入位置是正确的,为以酵母表达系统表达F1和F2,研究Mukteswar株与基因Ⅶ型毒株之间F蛋白的抗原性差异程度打下基础.  相似文献   

6.
A formalin-inactivated whole SIV vaccine confers protection in macaques   总被引:48,自引:0,他引:48  
A vaccine against human immunodeficiency virus (HIV) would be highly effective in stopping the acquired immunodeficiency syndrome (AIDS) epidemic. A comprehensive evaluation of potential vaccine methodologies can be made by means of the simian model for AIDS, which takes advantage of the similarities in viral composition and disease potential between simian immunodeficiency virus (SIV) infection of rhesus macaques and HIV infection in humans. Immunization with a formalin-inactivated whole SIV vaccine potentiated with either alum and the Syntex adjuvant threonyl muramyl dipeptide (MDP) or MDP alone resulted in the protection of eight of nine rhesus monkeys challenged with ten animal-infectious doses of pathogenic virus. These results demonstrate that a whole virus vaccine is highly effective in inducing immune responses that can protect against lentivirus infection and AIDS-like disease.  相似文献   

7.
新城疫病毒JZ05株F基因重组pGAPZα的构建   总被引:1,自引:0,他引:1  
以RT-PCR扩增新城疫病毒JZ05株,基因F1片段和F2片段,以核酸内切酶κpnI和XbaI对目的基因片段及质粒pGAPZαA进行酶切,连接酶切产物,转化Eacterium coli DH5α.以PCR方法确定JZ05 F1的阳性重组子为2个,JZ05 F2的阳性重组子为4个.对阳性重组子进行酶切鉴定及序列分析,结果发现,重组质粒pGAPZαA-F1、pGAPZαA-F2及质粒pGAPZαA的酶切电泳条带与试验设计大小相符;基因测序得到的重组子中F1和F2序列长度分别为1198bp、269bp,与新域疫病毒JZ05株F基因序列比对,其序列长度和核苷酸排列完全一致.这表明重组质粒中目的基因片段的核苷酸序列、大小和插入位置是正确的,为以酵母表达系统表达F1和F2、研究强毒株与弱毒株F蛋白的抗原性差异程度及研制重组亚单位疫苗打下了基础.  相似文献   

8.
采用逆转录聚合酶链式反应(RT-PCR)技术,从新城疫病毒洛阳分离株中扩增出HN基因片段,通过DNA重组技术将该基因片段重组于pcDNA3真核表达载体上,构建pcDNA3-HN重组质粒。通过用PCR扩增、酶切电泳分析的方法对重组DNA进行鉴定,成功构建了新城疫病毒洛阳分离株HN基因真核表达载体。  相似文献   

9.
根据GenBank登录的鸡新城疫病毒NP基因序列设计引物,利用RT—PCR对F48E9强毒株NP基因进行扩增,将扩增产物经纯化后连入pMD18-T载体,通过PCR和酶切鉴定出阳性重组质粒,经测序后获得F48E9 NP基因序列。经分析发现该基因的ORF总长为1470bp,编码489aa,NP蛋白有4个高度保守的Cys位点,分别位于第55、78、139、213位,且在401~440位和461~481位区域变异较大。将F48E9株与19株参考毒株的相应序列进行比较得到核苷酸序列同源性为87.9%~92.3%,氨基酸序列同源性较高,为92.2%~98.0%,遗传进化分析表明F48E9株相对独立,与参考毒株的遗传距离较远。  相似文献   

10.
 从含有禽流感病毒A/Goose/Guangdong/1/96 (H5N1)核蛋白 (NP)基因的质粒pUCNP中切下NP基因片段 ,将其亚克隆到pSY5 38质粒 ,再将带有痘苗病毒启动子P11的LacZ基因也平端克隆到pSY5 38质粒 ,然后切下同时含有NP及LacZ基因的片段 ,再亚克隆到禽痘病毒载体pSY6 81,从而构建出表达核蛋白基因的重组禽痘病毒转移载体pSY(NP +LacZ)。应用脂质体介导的方法将转移载体转染已感染禽痘病毒S FPV 0 17的鸡胚成纤维细胞 ,在X gal存在的条件下 ,利用蓝白斑筛选、数轮蚀斑纯化以及PCR、Western blot鉴定 ,结果证明 ,获得了能高效表达AIVNP蛋白的重组禽痘病毒rFPV NP。SPF鸡体内的免疫保护试验结果表明 ,它能够诱导机体产生较高水平的NP特异性抗体 ,并对H5N1和H7N1这 2种亚型高致病力禽流感病毒的攻击提供一定的保护。  相似文献   

11.
萝卜病毒病与过氧化物酶关系的初探   总被引:1,自引:0,他引:1  
萝卜接种TuMV病毒后过氧化物酶活性和同功酶电泳研究表明:萝卜对芜菁花叶病毒的抗性与叶片中过氧化物酶活性呈显著正相关。抗病的萝卜材料不管是否接种TuMV,过氧化物酶活性都明显高于感病植株。抗病萝卜最高达215.58酶活单位,感病萝卜最低的只有97.59酶活单位;前者比后者高121.13%。感病萝卜不接种病毒时,叶片中过氧化物酶活性很低。接种病毒后增加较多,但绝对数值还低于抗病萝卜。抗病萝卜叶片中过氧化物酶同功酶带宽于感病萝卜。初步认为过氧化物酶变化是萝卜抗病毒病的内在因素之一。  相似文献   

12.
Anti-idiotypic antibody vaccine for type B viral hepatitis in chimpanzees   总被引:21,自引:0,他引:21  
Anti-idiotypic antibodies (anti-Id) that contain an internal image component that mimics the surface antigen of hepatitis B virus (HBsAg) were used to immunize chimpanzees. Four injections of the rabbit anti-Id preparation elicited an antibody response to HBsAg (anti-HBs). The antibody specificity appeared to be against the anti-Id, since the anti-Id immunogen was shown to bind the chimpanzee anti-HBs. Two chimpanzees immunized with the anti-Id, along with two control animals that were either untreated or received a nonimmune rabbit immunoglobulin G preparation, were challenged with infectious hepatitis B virus. Both control chimpanzees developed clinical and serological characteristics consistent with an active hepatitis B virus infection, whereas the two anti-Id treated chimpanzees were protected from infection. Since chimpanzees provide a relevant model of a human response to hepatitis B virus immunization and infection, these results indicate that anti-Id preparations such as that described here might be candidates for vaccines against human diseases.  相似文献   

13.
本病是在我国发现的尚未见报道的丹顶鹤病毒性传染病。患鹤肝脏肿大。实验表明,人工感染雏鹅和成年鹅能引起发病和死亡;该病毒还可致死鹅胚、鸭胚和鸡胚,并能在鹅胚和鸭胚成纤维细胞上产生细胞病变。该病毒有囊膜,呈球形,大小约为130-180nm,无囊膜颗粒为95-105nm在CsCl里浮密度为1.29-1.34g/cm#+3,沉降系数为83.4s,对pH3.0敏感,而对pH5.0有抵抗力,1克分子MgCl#-2溶液对病毒无保护作用。该病毒不凝集禽类及动物红细胞。中和试验表明本病毒与小鹅瘟病毒、新城疫病毒、鸡马立克氏病病毒、法氏囊病病毒、鸭瘟病毒、小鸭肝炎病毒和猪瘟病毒没有抗原关系。  相似文献   

14.
本文对人工感染传染性法氏囊病病毒(IBDV)雏鸡接种新城疫(ND)疫苗后的红细胞凝集抑制(Hi)抗体滴度和免疫保护力进行了检测。结果表明,人工感染IBDV雏鸡一次接种ND疫苗后的Hi抗体滴度和免疫保护力,明显低于未感染IBDV的对照雏鸡;人工感染IBDV雏鸡二次接种ND疫苗后的Hi抗体滴度和免疫保护力,比一次接种ND疫苗时明显升高。  相似文献   

15.
朱静  张娟  姚艳  段旭  林钟婷 《安徽农业科学》2011,39(2):1026-1027,1029
[目的]比较白腰文鸟与三黄鸡雏鸡接种新城疫疫苗后的抗体水平,进一步确定其抵抗新城疫病毒侵害的能力。[方法]对白腰文鸟和三黄鸡接种新城疫疫苗,通过血液凝集试验(HA)和血液凝集抑制试验(HI)测定其接种对象血液中的抗体水平。[结果]在免疫接种后测定其HI抗体效价,白腰文鸟及三黄鸡的免疫抗体监测合格率均〉80%。[结论]白腰文鸟的抗体水平达到峰值的速度均优于三黄鸡。  相似文献   

16.
鸽Ⅰ型副粘病毒的研究   总被引:7,自引:0,他引:7       下载免费PDF全文
本文探讨了鸽Ⅰ型副粘病毒(鸽PMV—1)人工感染病鸽的临床症状,鸽PMV—1的抗原性、生物和理化特性以及对鸡的致病性,并与鸡新城疫病毒(NDV),特别是速发型亲内脏性新城疫病毒株(VVNDV)进行了比较。此外,初步测试了几种常用的鸡新城疫疫苗对鸽抗NDV或抗鸽PMV—1的免疫效果;对广州、深圳地区的鸽子进行了鸽PMV—1感染的血清学调查。  相似文献   

17.
Thirteen strains of monoclonal antibodies(McAbs) against infections bursal disease virus(IBDV) were obtained by using hydridoma technique and their characteristics were studied by double immunodiffusion,enzyme-linked immunosorbent assay(ELISA),virus neutralization test(VNT) and Western-blotting assay (WBA).The result showed that nine of the thirteen McAbs belonged to IgG class and four of them belonged to IgM class.No crossreactions were detected betwween the McAbs and Newscastle disease virus (NDV),infectious bronchitis virus(IBV) and Marek‘s disease virus(MDV).All of McAbs were positively specific reactive with IBDV and five of them can neutralize viral infectivity.Their recognized epitopes of the neutralizing McAbs were all presented on VP2 of the IBDV.  相似文献   

18.
利用表达H5亚型禽流感病毒血凝素基因的重组鸡痘病毒疫苗免疫SPF鸡和无母源抗体的商品鸡,通过比较免疫后血凝抑制(HI)抗体应答水平、攻毒后发病率和死亡率等指标评价其免疫保护作用。免疫后21d,重组鸡痘病毒免疫组仅有13%~20%鸡的HI抗体检测呈阳性。在同亚型禽流感病毒攻击后,重组鸡痘病毒疫苗免疫组产生了100%的保护率,而未免疫组全部死亡。结果表明:重组鸡痘病毒疫苗不能激发高滴度HI抗体应答,但可抵御同亚型禽流感病毒致死性攻击,保护效果达到或优于目前应用的灭活苗,显示出良好的应用前景。  相似文献   

19.
分别从陕西咸阳、兴平、杨凌、柔谷、眉县、岐山、凤翔等地采集辣椒病毒病标样126份,在室内通过单斑分离及回接验证得到5种分离物,采用鉴别寄主的生物学反应和DA S-EL ISA法鉴定,结果表明,引起陕西辣椒病毒病的毒原有黄瓜花叶病毒(CM V)、烟草花叶病毒(TM V)、烟草蚀纹病毒(TEV)、马铃薯Y病毒(PVY)和蚕豆萎蔫病毒(BBW V),其中CM V和TM V是优势毒原种群,分别占检测样品的60.31%和30.94%。在室内分别以CM V和TM V的枯斑寄主苋色藜和心叶烟为测试寄主,采用半叶法对接种叶片分别于接种前和接种后涂施病毒抑制剂,测试了7种病毒抑制剂的抑制效果。结果表明,接种前后涂施3.85%病毒必克水乳剂500倍液,均对黄瓜花叶病毒和烟草花叶病毒有很好的防治效果,且接种前涂施的防治效果较接种后涂施的防治效果好。  相似文献   

20.
In cats, infection with T-lymphotropic retroviruses can cause T-cell proliferation and leukemia or T-cell depletion and immunosuppression. In humans, some highly T4 tropic retroviruses called HTLV-I can cause T-cell proliferation and leukemia. The subgroup HTLV-II also induces T-cell proliferation in vitro, but its role in disease is unclear. Viruses of a third subgroup of human T-lymphotropic retroviruses, collectively designated HTLV-III, have been isolated from cultured cells of 48 patients with acquired immunodeficiency syndrome (AIDS). The biological properties of HTLV-III and immunological analyses of its proteins show that this virus is a member of the HTLV family, and that it is more closely related to HTLV-II than to HTLV-I. Serum samples from 88 percent of patients with AIDS and from 79 percent of homosexual men with signs and symptoms that frequently precede AIDS, but from less than 1 percent of heterosexual subjects, have antibodies reactive against antigens of HTLV-III. The major immune reactivity appears to be directed against p41, the presumed envelope antigen of the virus.  相似文献   

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