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1.
An enzyme-linked immunosorbent assay (ELISA) was applied to evaluate the antibody response of commercial White Leghorn chickens to vaccination against Marek's disease (MD) at hatch (day 0) with serotype-1 (Rispens), -2 (SB-1), or -3 (turkey herpesvirus, HVT) vaccine virus and to challenge on day 21 with MD virus. Antigens for the test were whole chicken embryo fibroblast cells infected with Rispens, SB-1, or HVT. The chickens were progeny of stock that had been vaccinated with HVT, and on day 21 the nonvaccinated group had higher levels of maternal antibodies to HVT than to other antigens (P < 0.05). Only SB-1 vaccine had induced antibodies by day 21, and this was detected only against homologous antigens. On day 49, all three vaccines had induced higher levels of antibodies to homologous than to heterologous antigens. Marek's Disease virus (MDV) induced antibodies to all three antigens, but challenging vaccinated chicks did not significantly increase levels of antibodies on day 81 to any of the three antigens. It was concluded that an ELISA using whole cells as antigens would have potential value for monitoring the antibody response induced by MD vaccines and virulent MDV.  相似文献   

2.
The major histocompatibility complex (MHC) is a part of the immune system which presents epitopes of intracellular antigens on the cell surface. MHC molecules have receptor-ligand binding affinities with T lymphocytes, permitting the latter to detect foreign intracellular infectious agents. Some pathogens, such as herpesviruses, have developed strategies of evading the host response by MHC. This pressure on the immune system brought, in turn, improvements in the antigen-presenting pathway, for example through the effect of interferon (IFN), which can upregulate MHC expression. The main objective of this work was on the one hand, to determine the abilities of three strains of Marek's disease virus (MDV), a chicken herpesvirus, in interfering with the expression of MHC class I molecules in chicken embryo fibroblasts. On the other hand, we analyzed the ability of IFN to reinstate this important immune capability to the infected cells. Our results show that only an oncogenic serotype 1 strain of MDV (RB1B) was able to markedly decrease MHC class I expression, and that addition of IFN reversed this MDV effect.  相似文献   

3.
HVT国内株的分离鉴定   总被引:3,自引:0,他引:3  
用来自国内某火鸡饲养场的健康火鸡血白细胞 ,接种于鸡胚成纤维细胞 ,分离到一株火鸡疱疹病毒的野毒—SY8_2。电镜下可观察到分离株SY8_2的鸡胚成纤维细胞培养物中存在典型的火鸡疱疹病毒粒子 ;分离株SY8_2的细胞培养物经卵黄囊途径接种 4日龄鸡胚 ,14天后在绒毛尿囊膜上形成痘斑 ;用分离物SY8_2细胞培养物接种 1日龄SPF雏鸡 ,感染雏鸡可产生病毒血症 ,并能从感染雏鸡的血液白细胞中重新分离到病毒 ;经 2个月的临床观察人工感染鸡无不良反应 ,剖检无任何病理解剖学变化 ;用HVT特异性单克隆抗体L78(3型 )做间接免疫荧光染色试验证实分离株SY8_2为MD血清 3型病毒—HVT。  相似文献   

4.
5.
鸡传染性法氏囊病(IBD)是一种严重危害养禽业的高度致死性和免疫抑制性传染病。为研制IBD重组火鸡疱疹病毒(HVT)活载体疫苗,本研究构建了表达鸡传染性法氏囊病病毒(IBDV)保护性抗原VP2基因的重组HVT并对其体外生物学特性进行了分析。通过RT-PCR扩增IBDV超强毒株VP2基因并克隆入pCI载体,获得重组真核表达质粒pCI-VP2。用限制性内切酶将携带CMV启动子的VP2基因表达框架切下,连接于入门质粒pENTR,构建获得重组入门质粒pENTR-VP2。将pENTR-VP2与HVT重组黏粒H3-Kan/ccdB进行LR重组反应,构建重组表达黏粒H3-VP2。用H3-VP2与其他4个相互重叠并覆盖HVT全基因组的黏粒共同转染鸡胚成纤维细胞(CEF),拯救获得重组病毒rHVT-VP2。将重组病毒在CEF中连续传至20代后用PCR、间接免疫荧光试验和免疫印迹试验进行检测,并绘制重组病毒体外生长曲线,分析其体外复制特性。结果表明,重组病毒rHVT-VP2能够稳定表达VP2蛋白,rHVT-VP2在CEF中的复制能力与亲本病毒无明显差异。重组病毒rHVT-VP2免疫鸡后能够诱导产生IBDV中和抗体,并对IBDV强毒株攻击引起的死亡提供90%免疫保护。重组病毒rHVT-VP2的构建为研制IBD重组HVT活载体疫苗奠定了基础,对IBD的防控具有重要意义。  相似文献   

6.
新城疫病毒山东强毒株的分离鉴定   总被引:14,自引:1,他引:14  
从山东流行烈性传染病的鸡群中分离出7株具有血凝活性的病毒,该7株病毒的血凝活性均能被新城疫La Sota株标准阳性血清所抑制,但病毒不能被中和,仍能致死鸡胚。经分离鉴定,分离毒均为新成疫病毒株。通过鸡胚半致死量(ELD50)、最小致死量致鸡胚的平均时间(MDT)、1日龄雏鸡脑内致死指数(ICPI)、6周龄雏鸡静脉致死指数(IVPI)、血凝解脱及血凝素稳定性等试验表明:7株分离病毒均为新城疫病毒强毒性,其毒力与标准强毒株F48E9株相似。  相似文献   

7.
The Israeli vaccine strain of fowl poxvirus grows efficiently in chicken embryo fibroblasts but not in cell lines derived from monkey kidney or human fibroblasts. We developed two assays for the titration of the infectivity of this virus in secondary cultures of chicken embryo fibroblasts. The first is a focus assay, in which minimum essential medium and SeaKem ME agarose were used for the overlay media. Under these conditions, clear virus foci appeared after 5 days of incubation at 37 C. The second assay is a semiautomatic colorimetric test based on the ability of live cells in culture to reduce the yellow tetrazolium salt 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT; thiazolyl blue) to its formazan derivative. The reagent was added to infected chicken embryo fibroblasts in 96-well plates 10 days after infection. The formazan formed during 2 hr was extracted with dimethyl sulfoxide, and its absorbance was read by an automatic microplate spectrophotometer. A good correlation of the infectivity titers of the virus was obtained by the two methods.  相似文献   

8.
DNA has been isolated from herpesvirus of turkeys (HVT) virions and used to construct a partial gene library in pBR-322. The recombinants have been characterized and shown to contain HVT DNA inserts. A representative recombinant containing a 5.9-kilobase HindIII fragment was used as a probe to quantitate the yields of HVT DNA in vitro and to follow the kinetics of viral DNA replication. The data shown that in chicken fibroblasts, viral DNA synthesis initiates by about 12-14 hr postinfection and that the yield of progeny virus plateaus at 28-30 hr postinfection. Based upon quantitative hybridization to cloned DNA probes, we estimate that approximately 2000 HVT genomes are produced per infected cell in vitro; however, in vivo in persistently infected turkeys, the number of viral genomes was below the level of detection by Southern blotting.  相似文献   

9.
The reptilian paramyxovirus GOV replicated in chicken embryo fibroblasts, in embryonated chicken eggs and in explanted chorio-allantoic membrane with titres of up to 10(8.2) TCID50/ml at 28 degrees C. The virus did not multiply above 30 degrees C. GOV re-isolated from the avian host systems was identified by immunofluorescence and by immunogold-electron microscopy.  相似文献   

10.
Serotype 1 of infectious bursal disease virus (IBDV) adapted to chicken embryo fibroblasts (CEF) was used for the preparation of enzyme-linked immunosorbent assay (ELISA) antigen. After several passages of diluted viruses in CEF cultures, the titer of seed virus increased to 1.2 x 10(8) plaque-forming units/ml. Purified virus prepared from this seed virus had high titers of antigen and was less nonspecific than that from low titer of seed virus in an ELISA. The nonspecific reaction of purified virus decreased further after treatment with Triton X-100. When the specificity of this treated antigen was examined with specific-pathogen-free chicken sera before and during lay and with 14 antisera to some major avian viruses, this ELISA antigen had no nonspecific reaction and was specific to antibodies to serotypes 1 and 2 of IBDV.  相似文献   

11.
分别以7种鸡MD疫苗免疫SPF鸡和狼山鸡,用琼脂扩散试验(AGP)检查鸡群MDV强毒攻击后不同时期的羽囊抗原,结果表明,免疫组鸡羽囊排毒高峰推迟,排毒率下降,排毒高峰维持时间短,不同疫苗免疫不同品种鸡后排毒情况有差异,CVI988和两种二价苗效果优于HVT苗。  相似文献   

12.
The mechanisms of Marek's disease virus (MDV) entry to host cells have not yet been analyzed. Heparan sulfate (HS) on the cell surface serves as a receptor for several herpesviruses in mammalian species. In this study, we demonstrated that plaque formation by cell-free MDV is inhibited by the addition of soluble heparin to the cell culture. Moreover, pretreatment of susceptible cells, chicken embryo fibroblasts, with heparinase, partially reduced infectivity of the cell-free MDV. From these results, it was suggested that the MDV entry, at least in the case of cell-free MDV, is dependent on the presence of cell surface glycosaminoglycans, principally HS.  相似文献   

13.
鸡胚因发育过程清楚,长久以来作为基础和应用科学研究领域重要的实验模型,尤其在鸡胚发育早期绒毛尿囊膜阶段,因其血管丰富,是天然的免疫缺陷宿主,是病理学、药理学和肿瘤学等研究领域的理想实验模型。作者简述了发育早期的鸡胚组织结构,并介绍了鸡胚绒毛尿囊膜在肿瘤研究、血管生成、器官移植、烧伤等疾病机理研究中的应用,以及在鸡胚病理模型基础上进行的抗肿瘤药物筛选的应用。重点介绍了鸡胚及禽类细胞系在病毒繁殖和疫苗生产、治疗性蛋白和单抗生产方面的应用研究进展。多种人源病毒、禽源病毒、支原体等可在鸡胚及禽类细胞上增殖,并用于疫苗生产。作者对常用的禽类纤维原细胞和多能干细胞的发展和特点进行了阐述,并总结了商业化的禽类细胞系来源以及部分易感病毒。鸡胚表达系统能够在目的蛋白特定位点产生人源化糖基,减少目的蛋白对人的过敏反应,且禽蛋廉价易得,可作为生产人用单克隆抗体和治疗性蛋白的合适供体。作者介绍了鸡胚及禽类细胞系在生物医药领域应用的最新进展,并对鸡胚作为动物模型在未来的应用进行了展望。  相似文献   

14.
Chicken embryo has long been an important experimental model in basic and applied science because of its clear development process,especially in the early development of chicken embryo chorioallantoic membrane stage,due to its abundant blood vessels,it is a natural immunodeficiency host and can be used as an ideal experimental model for pathology,pharmacology and oncology research.The authors briefly described the tissue structure of early stage of chicken embryo,the application of chick embryo chorioallantoic membrane model in tumor,angiogenesis,organ transplantation,burn and other diseases,and the application of anti-cancer drug screening based on the pathological model of chicken embryo.The advances in the application of chicken embryo and avian cell lines in virus reproduction,vaccine production,therapeutic protein production and monoclonal antibody production were reviewed.A variety of human viruses,avian viruses and mycoplasma can proliferate in chicken embryos and avian cell lines and be used in vaccine production.In this paper,the development and characteristics of commonly used avian fibroblasts and pluripotent stem cells were described,and the source of commercial avian cell lines and some susceptible viruses were summarized.Chicken embryo expression system can produce human glycosylates at specific sites of target proteins,reduce the allergic reaction of the target protein to human,and poultry eggs are cheap and easily available,so it can be used as a suitable donor for the production of human monoclonal antibodies and therapeutic proteins.In this paper,the recent progress in the application of chicken embryos and avian cell lines in the field of biomedicine was introduced,and the future application of chicken embryos as animal models was forecasted.  相似文献   

15.
以简便技术制备鸡胚皮肤(CES)细胞,进而进行了鸡马立克氏病(MD)SB-1株病毒适应于CES细胞和致CES细胞病变效应(CPE)的研究.试验表明,在形成CPE的细胞中可检出核内包涵体,MD的SB-1株病毒的CES细胞毒的蚀斑形成单位(pfu)为105.7201-7.2122/m L.本研究为以后用CES细胞增殖SB-1株病毒以代替鸡胚成纤维细胞(CEF)制造疫苗提供了依据.  相似文献   

16.
番鸭"花肝病"病原的研究   总被引:1,自引:0,他引:1  
文章对番鸭"花肝病"病原进行了研究,证实病原为番鸭呼肠孤病毒。该病毒大小为50nm-70nm左右,圆形,无囊膜;雏番鸭人工感染该病毒后可出现和自然病例相同的临床症状和病理变化,并能回收到病毒,鸡、麻鸭人工感染不发病;该病毒不凝集鸡、鸭的红细胞,能够在鸡胚、番鸭胚成纤维细胞上增殖并出现明显的细胞病变;核酸类型为RNA,琼扩试验表明与禽呼肠孤病毒有血清学交叉反应。  相似文献   

17.
为了更好的进行口蹄疫(foot and mouth disease,FMD)疫苗研制,本试验进行了口蹄疫疫苗免疫原含量和免疫效果的关系研究。试验中提取了口蹄疫疫苗中的主要免疫原、沉降系数为146S的口蹄疫完全病毒颗粒,分不同剂量免疫豚鼠,分别采集1次免疫和加强免疫的血清,用细胞微量中和试验检测中和抗体滴度,研究免疫效果。结果表明,当免疫的口蹄疫病毒颗粒含量大于1.5 μg 时,增加免疫量不能增加中和抗体滴度,当免疫量大于7.5 μg时,中和抗体滴度有所下降。该研究结果对于开发口蹄疫疫苗具有指导意义。  相似文献   

18.
Adaptation of Marek's disease virus to the Vero continuous cell line   总被引:2,自引:0,他引:2  
Marek's disease virus (MDV) is a highly infectious, cell-associated oncogenic herpesvirus. Production of MD vaccines has been limited to primary chicken and duck embryo fibroblast (CEF and DEF) cultures. These have a limited life span and cannot be readily stored in liquid nitrogen. Moreover, the need to prepare CEF and DEF cells on a regular basis from 10 to 11 day-old embryos derived from a flock that must be tested continuously for the presence of avian pathogens adds to the cost of vaccine production. A continuous cell line that would support MDV replication could have significant advantages for the rapid large-scale preparation of MD vaccines. In this report, we describe the adaptation to growth of CEF-grown preparations of serotype 1 and serotype 3 (herpesvirus of turkeys; HVT) strains of MDV in cells of the Vero continuous cell line. Although both viruses produced typical CPE, higher levels of infectious progeny and more extensive virus-specific immunofluorescence were obtained for HVT than for the serotype 1 virus. PCR and pulsed field electrophoresis (PFE) analysis of the DNA from Vero cells infected with either virus confirmed the presence of virus-specific DNA.  相似文献   

19.
A reproducible enzyme-linked immunosorbent assay (ELISA) using Marek's disease virus (MDV)-infected cells for the detection of antibodies to MDV is described. The optimum number of MDV-infected chicken embryo fibroblasts (CEF) was 5 X 10(4)/well, and test sera were positive at 1:400 dilutions. Compared with a purified virus preparation, MDV-infected CEF produced high specific and low nonspecific reactivities. Wells coated with whole cells could be stored at 4 C or -20 C for at least 3 months without loss of reactivity. With antibody-negative sera, the cutoff absorbency was 0.20 units. The ELISA was 20-to-40-fold more sensitive than indirect immunofluorescence. Homologous combinations of antisera in wells coated with CEF infected with different MDV serotypes were more reactive at higher dilutions than were heterologous combinations. The procedure described is specific and suitable for large-scale screening of both chicken and monoclonal antibodies against MDV.  相似文献   

20.
Recombinant strains of herpesvirus of turkeys (HVT) were constructed that contain either the fusion protein gene or the hemagglutinin-neuraminidase gene of Newcastle disease virus (NDV) inserted into a nonessential gene of HVT. Expression of the NDV antigens was regulated from a strong promoter element derived from the Rous sarcoma virus long terminal repeat. Recombinant HVT strains were stable and fully infectious in cell culture and in chickens. Chickens receiving a single intra-abdominal inoculation at 1 day of age with recombinant HVT expressing the NDV fusion protein had an immunological response and were protected (> 90%) against lethal intramuscular challenge at 28 days of age with the neurotropic velogenic NDV strain Texas GB. Recombinant HVT expressing the NDV hemagglutinin-neuraminidase provided partial protection (47%) against the same challenge. Chickens vaccinated with recombinant HVT vaccines had low levels of protection against NDV replication in the trachea when challenged ocularly. Recombinant HVT vaccines and the parent HVT strain provided similar levels of protection to chickens challenged with the very virulent RB1B strain of Marek's disease virus, indicating that insertion of foreign sequences into the HVT genome did not compromise the ability of HVT to protect against Marek's disease.  相似文献   

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