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1.
非洲猪瘟(African swine fever,ASF)是由非洲猪瘟病毒(African swine fever virus,ASFV)感染猪引起的一种急性、烈性、高度接触性传染病,至今没有研发出安全有效的疫苗,一旦暴发会造成重大经济损失。ASFV在和宿主长期作用过程中,通过抑制干扰素和炎症反应,调节凋亡、自噬及细胞免疫等多种途径逃逸机体免疫反应促进自身复制,但具体的机制仍不完全清楚。ASFV复杂的免疫逃逸机制可能是阻碍有效疫苗研发的关键因素之一。借助生物信息学技术对ASFV的基因组和蛋白质组深入分析,筛选病毒的免疫调控关键基因和保护性抗原表位,将在ASFV免疫逃逸分子机制的研究与疫苗研发中发挥重要作用。本文主要对ASFV感染引起的免疫应答反应及可能的免疫逃逸机制研究进行概述,以期为ASF疫苗研制及综合防控提供思路。  相似文献   

2.
To study the clinicopathology and histopathology of African swine fever (ASF), and to explore the internal relationship between pathological changes and disease occurrence and development and its pathological mechanism, 13 Landrace pigs with bodyweight about 20 kg were intramuscular injected with African swine fever virus (ASFV), strain Pig/HLJ/18 at a dose of 102HAD50·mL-1. During the experiment, all the dead pigs were systematically dissected and sampled, paraffin sections were produced, and haematoxylin-eosin staining was performed. Clinicopathological evaluation standards for acute ASF were established, then pathological lesions (classification variables) were expressed by counting frequency and percentage, and the lesion degree (continuous variables) was graded and scored according to different pathological changes of various tissues and organs. The results showed that all infected pigs were in line with the clinical characteristics of ASF, including acute, febrile and highly infectious, with a 100% incidence rate and 100% mortality. The dead pigs showed typical characteristics of septicemia, cadavers prone to corruption, blood clotting adverse or hemolysis, rigor mortis incomplete. The main pathological lesions were hemorrhagic necrotizing lymphadenitis, acute inflammatory splenomegaly (septic spleen), cerebral edema, pulmonary edema and lung consolidation et al. The spleen and lymphonodus are the target organs attacked by ASFV, with the most significant lesions, the earliest occurrence time, the longest duration and the highest frequency. The most prominent pathological changes are blood circulation disorders, including multiple pathological manifestations such as edema, hyperemia, congestion, hemorrhage, infarction, disseminated intravascular coagulation (DIC), and the most important characteristics are hemorrhagic lesions. The inflammatory reaction of lymphocytic exudation caused by ASFV runs through the whole process, especially in the middle and later stages of the course. The results suggest that the main pathological process of acute African swine fever is a typical immune/inflammatory cascade reaction and severe systemic blood circulation disorder, which resulted in the high incidence rate and high mortality rate of acute ASF.  相似文献   

3.
急性非洲猪瘟的实验病理学研究   总被引:1,自引:1,他引:0  
旨在通过对非洲猪瘟临床病理学和组织病理学的研究,探讨病理学变化与疾病发生发展的内在关系及其病理机制。选用体重20 kg左右的长白猪13头,肌内注射非洲猪瘟病毒毒株Pig/HLJ/18,剂量102HAD50·mL-1。试验期间的死亡猪,全部进行系统剖检和取材,制备石蜡切片,苏木素伊红染色。建立病理学评价标准,病变(无序分类变量)用频率和百分比表示,病变程度(有序分类变量)按各组织器官的不同病变进行分级和评分。结果表明,发病猪符合非洲猪瘟急性、热性、高传染性等临床特征,发病率100%,病死率100%。病死猪表现败血症典型特征,尸体易腐败,血凝不良或溶血,尸僵不全。主要病理损伤为出血性坏死性淋巴结炎、急性炎性脾肿(败血脾)、脑水肿、肺水肿和肺实变等。脾和淋巴结是非洲猪瘟病毒攻击的靶器官,病变最为显著,出现时间最早,持续时间最长,发生频率最高。病理变化以血液循环障碍尤为突出,包括水肿、充血、淤血、出血、梗死和弥散性血管内凝血等多种病理表现,出血性病变为其最主要的特征。非洲猪瘟病毒引发的以淋巴细胞渗出为主的炎症反应贯穿始终,在病程的中后期表现更为明显。结果提示,急性非洲猪瘟的主要病理过程为典型的免疫/炎症级联反应和严重的全身血液循环障碍,共同导致急性非洲猪瘟的高发病率和高死亡率。  相似文献   

4.
Lymph nodes, spleen, liver, lung and kidney obtained from pigs experimentally infected with two African Swine Fever Virus (ASFV) isolates of differing virulence were fixed by perfusion with glutaraldehyde and embedded in paraffin. An immunoperoxidase technique using a polyclonal anti-ASFV serum was performed on tissue sections in order to detect ASFV antigen. The distribution of ASFV antigen in such infected organs is shown and the differences between both infections compared and discussed. Monocytes, macrophages, hepatocytes, endothelial cells, neutrophils and epithelial cells were found to contain ASFV antigens.  相似文献   

5.
非洲猪瘟血清学诊断靶点的研究进展   总被引:4,自引:4,他引:0  
非洲猪瘟(African swine fever,ASF)是一种由非洲猪瘟病毒(African swine fever virus,ASFV)引起的猪高致死性传染病.ASFV编码蛋白p30、p54和p72等具有较高的免疫原性,且部分氨基酸序列较为保守,常被作为血清学诊断靶点,用于评价ASF不同阶段或发病程度的抗体水平变...  相似文献   

6.
African swine fever (ASF) is an infectious disease caused by the African swine fever virus (ASFV). In order to ensure the accuracy and reliability of the test results,it is necessary to develop positive standard control products used in the kit. The study was aimed to develop the virus-like particles containing African swine fever virus (ASFV) nucleic acid sequence and its application in detection method. Fristly,the full-length gene fragment of p72 gene was amplified, and the ASF DNA virus-like particles containing p72 gene was constructed using insect baculovirus system. In order to further validate the reliability of the virus-like particles in the application of the method,DNA nucleic acid was extracted simultaneously with the cultured virus and infected tissue sample and applied in the Real-time quantitative PCR method. The results showed that the virus-like particles prepared by this study could replace the ASFV as a positive control product in the Real-time quantitative PCR method, and could act as quality control during nucleic acid extraction process. In the fluorescent PCR detection kit, the lowest packaging concentration of virus-like particles was 102 TCID50. Further studies had shown that the virus-like particles were also suitable for common PCR and LAMP detection methods, the minimum concentration were 103 and 101 TCID50, respectively. The results of this study would be important for the ASF detection method, promoting the application of the method and ensuring the accuracy and reliability of the test results.  相似文献   

7.
非洲猪瘟(African swine fever,ASF)是由非洲猪瘟病毒(African swine fever virus,ASFV)引起的烈性传染病,为了保证其检测结果的准确性和可靠性,需要研制试剂盒中使用的阳性标准质控品。本试验旨在研制含ASFV核酸序列的病毒样颗粒,并探究其在检测方法中的应用。首先扩增p72基因的全长片段,利用昆虫杆状病毒系统,包装出含有p72基因的ASF DNA病毒样颗粒。为了进一步验证该病毒样颗粒在应用中的可靠性,本研究将病毒样颗粒与ASF的组织毒及细胞毒同时进行DNA核酸提取,进行实时荧光定量PCR。结果表明,本研究制备的病毒样粒子能很好的取代ASFV在实时荧光定量PCR检测方法中作为阳性质控品,且能对核酸提取过程进行质控,实时荧光定量PCR检测试剂盒中,病毒样粒子的最低包装浓度为102 TCID50。进一步研究发现该病毒样颗粒也适用于普通PCR及LAMP检测方法中,最低浓度分别为103和101 TCID50。本试验结果将为规范ASF检测方法,促进ASF检测方法的转化应用及保证检测结果的准确度和可靠性提供科学依据。  相似文献   

8.
The Mkuze Game Reserve (MGR), in north-eastern KwaZulu-Natal Province, South Africa is an African swine fever virus (ASF) controlled area. In a survey conducted in 1978, ASF prevalence in warthogs and Ornithodoros ticks in MGR was determined to be 2% and 0.06%, respectively. These values, acknowledged as being unusually low compared to other East and southern African ASF-positive sylvatic-cycle host populations, have not been assessed since. The availability of a sensitive PCR-based virus detection method, developed specifically for the sylvatic tampan host, prompted a re-evaluation of ASF virus (ASFV) prevalence in MGR ticks. Of the 98 warthog burrows inspected for Ornithodoros presence, 59 (60.2%) were found to contain tampans and tick sampling was significantly male-biased. Whilst gender sampling-bias is not unusual, the 27% increase in infestation rate of warthog burrows since the 1978 survey is noteworthy as it anticipates a concomitant increase in ASFV prevalence, particularly in light of the high proportion (75%) of adult ticks sampled. However, despite DNA integrity being confirmed by internal control amplification of the host 16S gene, PCR screening failed to detect ASFV. These results suggest that ASFV has either disappeared from MGR or if present, is localized, occurring at exceptionally low levels. Further extensive surveys are required to establish the ASFV status of sylvatic hosts in this controlled area.  相似文献   

9.
为了进一步做好非洲猪瘟疫情防控工作,研究用实时荧光PCR法对武威市某养殖场病死野猪的猪耳朵和猪鼻拭子样品进行了非洲猪瘟病毒检测。结果显示该养殖场病死猪耳样品和猪鼻拭子样品均无Ct值,线形为直线,表明所有被检测样品均为ASFV抗原阴性。研究为严防非洲猪瘟进入威武市奠定了坚实的技术储备,也为威武市非洲猪瘟疫情防控提供了一定参考。  相似文献   

10.
环介导恒温扩增技术快速检测非洲猪瘟病毒   总被引:1,自引:0,他引:1  
以人工合成的非洲猪瘟病毒(ASFV)P72全长基因为模板,利用在线软件Primer Explorer4设计环介导恒温扩增(LAMP)的内、外引物,通过对反应体系和反应条件进行优化,建立了ASFV的LAMP检测方法,同时进行了敏感性和特异性试验。结果表明,所建立的LAMP检测方法最低检测限可达10拷贝质粒DNA,且具有良好的特异性,LAMP产物的酶切鉴定也验证了反应的特异性。对凝胶电泳后紫外观察、肉眼观察颜色变化、生成沉淀观察以及实时荧光PCR扩增曲线Ct值判定等不同判定方法进行比较表明,以上结果判定方法各有其优缺点,其中荧光PCR的敏感性最高,染色法相对较方便直观,电泳法敏感性稍低。  相似文献   

11.
非洲猪瘟(African swine fever,ASF)是由非洲猪瘟病毒(African swine fever virus,ASFV)引起的一种急性、热性、高度传染性疫病,感染猪以发热和全身性出血为主要特征,病程短、病死率高。非洲猪瘟主要流行于非洲国家,随后相继传入西欧、南美洲、东欧,以及亚洲国家,对全球养猪业、食品安全和猪及其产品国际贸易产生了严重危害和深远影响。现结合参考文献和我国非洲猪瘟发生、控制情况,分析了非洲猪瘟病毒传播动力学、传播方式,提出防控非洲猪瘟的主要措施。  相似文献   

12.
非洲猪瘟(African swine fever,ASF)是由非洲猪瘟病毒(African swine fever virus,ASFV)引起的家猪和野猪的急性、出血性传染病,强毒株感染猪的致死率接近100%,给养猪业造成巨大经济损失。ASFV在猪群中可以快速有效传播,在环境中可稳定存在,为ASF的防控带来了挑战。研究人员一直致力于ASF疫苗的研究,迄今为止,仍没有有效的疫苗投入市场。综述了ASF灭活疫苗、减毒活疫苗、亚单位疫苗、DNA疫苗、病毒活载体疫苗的研究情况,以期为ASF疫苗的有效研发提供参考。  相似文献   

13.
非洲猪瘟缺乏安全有效的疫苗,其防控有赖于及时、准确的诊断和消毒灭源.本研究在对非洲猪瘟病毒(Afri-can swine fever virus,ASFV)B646L基因序列进行分析的基础上设计引物、探针,建立了基于微芯片的ASFV免提取荧光PCR检测技术.特异性试验结果显示,微芯片PCR可用于我国不同地区ASFV毒株...  相似文献   

14.
African swine fever (ASF) is a devastating disease caused by African swine fever virus (ASFV), characterized by acute feature, high fever, high mortality and other characteristics. ASF mainly outbreaks in African, Eastern Europe countries, Russia and Caucasus region. At present, there are no vaccine available and effective control strategies against ASFV spread, therefore, ASF has a serious impact on the pig industry in the affected countries. The major target cells of the virus are swine reticuloendothelial cells and monocyte-macrophage cells. ASFV can result in apoptosis and affect the host's immune system, and then show the characteristics of the corresponding disease. ASFV has the characteristics of large genome, more genotype and more variability. In this paper, the molecular etiology and pathogenesis of ASFV are reviewed, so as to provide theoretical basis for prevention and control of ASF.  相似文献   

15.
自2018年8月以来,非洲猪瘟已成为我国养猪业的头号疫病,对养猪业造成了巨大损失。基于聚合酶链式反应(PCR)的核酸检测方法具有高灵敏性和高特异性,在对非洲猪瘟的诊断、感染监控和养殖复产过程中生物安全评价等方面发挥了重要的作用。文章对常用的核酸检测技术与特点、非洲猪瘟病毒核酸检测方法的应用、核酸检测新技术展望3个方面进行了总结,以期为养猪企业在非洲猪瘟核酸检测和监测方面提供帮助。  相似文献   

16.
非洲猪瘟病毒的分子病原学及致病机理研究进展   总被引:1,自引:0,他引:1  
非洲猪瘟(African swine fever,ASF)是由非洲猪瘟病毒(African swine fever virus,ASFV)引起的一种烈性传染病,具有急性、高热、高病死率等特征,主要暴发于非洲、东欧国家、俄罗斯及高加索地区。目前,该病缺乏有效的疫苗和治疗方法,给病情爆发地区的养猪业造成严重的影响。ASFV的主要靶细胞是网状内皮细胞和单核-巨噬细胞,造成细胞凋亡,影响宿主的免疫系统,进而表现出相应的疫病特征。ASFV具有基因组较大、基因型较多且易变异等特征。文章主要从分子病原学和致病机理方面对ASFV的研究情况进行综述,为ASF的防控提供理论依据。  相似文献   

17.
非洲猪瘟(ASF)是由非洲猪瘟病毒(ASFV)感染引起的一种高度接触性传染病。由于ASFV的感染机制极为复杂,基因型多,至今尚无有效疫苗用于防控,防止该病暴发主要依赖于早期快速诊断和控制。为建立一种高效快速、特异的ASFV检测方法,根据ASFV的E184L基因序列,设计了TaqMan荧光定量PCR引物及探针,建立了检测ASFV的TaqMan荧光定量PCR方法。结果表明,该方法设计的引物具有高度特异性,以构建的重组质粒为标准品建立的TaqMan荧光定量PCR方法的标准曲线具有良好的线性关系,线性相关系数为0.992,对ASFV核酸最低检测限为1.51拷贝,且与伪狂犬病病毒、猪细小病毒、猪圆环病毒2型等不存在交叉反应。建立的基于ASFV E184L基因实时荧光定量PCR检测方法能够快速、准确、特异地对ASFV核酸进行定量分析,丰富了ASFV的检测方法。  相似文献   

18.
非洲猪瘟病毒无标签p30-ELISA抗体检测方法的建立及应用   总被引:1,自引:1,他引:0  
非洲猪瘟(African swine fever, ASF)是由非洲猪瘟病毒(African swine fever virus, ASFV)引起猪的一种急性、热性、出血性、高度接触性传染病,临床症状以败血症、皮炎和关节炎为特征,高发病率和高死亡率。为建立临床检测ASFV抗体的间接ELISA检测方法,本研究扩增了ASFV-CP204L基因,通过pET-30a原核表达系统表达p30蛋白,使用Ni-NTA纯化表达产物,通过肠激酶切除外源性蛋白,得到无His-组氨酸标签的p30蛋白,以此为诊断抗原,建立间接ELISA方法。结果显示:表达的无标签p30重组蛋白大小约为30 ku,与ASF阳性猪血清具有较好的反应原性;确定ELISA抗原包被浓度为1 μg·mL-1,根据ROC曲线下面积确定S/P值>0.398判定为阳性,批内、批间变异系数均<10%;与PCV2、CSFV、PRV-gE、PRRSV阳性血清无交叉反应与INGENASA商品化试剂盒总符合率为97.78%。用该方法分别检测标准阳性血清、动物感染试验血清和收集的区域性临床血清644份,该方法最低可检测到1∶512倍稀释的标准阳性血清样品;检测感染动物血清,其中80%(4/5)的试验动物在第10天抗体为阳性。644份临床猪血清样品中抗体阳性率为7.61%,其中,母猪、后备母猪、仔猪、保育猪和育肥猪抗体阳性率分别为3.03%、0%、4.94%、7.55%和28.7%。本试验建立的ASFV-p30间接ELISA方法具有良好的特异性、灵敏度和重复性,可应用于ASFV的抗体检测,为ASF的诊断和流行病学调查提供了技术手段。  相似文献   

19.
African swine fever (ASF) is an acute, highly contagious and deadly viral hemorrhagic fever of domestic pigs caused by African swine fever virus (ASFV), a double-stranded DNA virus of the family Asfarviridae. In this study, molecular diagnosis and characterization of outbreak ASFV in northern Tanzania, was performed on spleen, lymph node, kidney, and heart samples collected in June and July 2013 from domestic pigs that died during a hemorrhagic disease outbreak. Confirmatory diagnosis of ASF was performed using polymerase chain reaction (PCR) by partial amplification of B646L gene of ASFV encoding the major capsid protein p72 using PPA1/PPA2 primers. PCR using PPA1/PPA2 primers produced an expected PCR product size, confirming ASF outbreak in northern Tanzania. In addition, nucleotide amplification and sequencing, and phylogenetic reconstruction of the variable 3′-end of the B646L gene and complete E183L gene encoding the inner envelope transmembrane protein p54 showed that the 2013 outbreak ASFV from northern Tanzania were 100 % identical and clustered into ASFV B646L (p72) and E183L (p54) genotype X. Furthermore, the tetrameric amino acid repeats within the central variable region (CVR) of the B602L gene coding for the J9L protein had the signature BNBA(BN)5NA with a single novel tetramer NVDI (repeat code N). The results of the present study confirm an ASF outbreak in northern Tanzania in the year 2013 and show that the present outbreak ASFV is closely related to other ASFV from ticks, warthogs, and domestic pigs previously reported from Tanzania.  相似文献   

20.
非洲猪瘟病毒(ASFV)是非洲猪瘟(ASF)的病原,可引发家猪和野猪急性、传染性出血死亡,目前尚无有效的疫苗和抗病毒药物。ASFV是囊膜病毒,其囊膜蛋白的结构和功能可能是影响病毒入侵和细胞嗜性的重要因素。病毒入胞是病毒感染细胞的第一步,通常是通过细胞表面特定的分子与病毒蛋白相结合吸附于宿主细胞表面,对ASFV入胞过程的病毒蛋白或宿主因子为靶点或可有效抑制ASFV的复制。本文从ASFV入胞过程中起重要作用的囊膜蛋白出发,对ASFV的入胞分子机制进行综述,为ASFV入胞深入研究以及治疗性药物和疫苗的研发提供参考。  相似文献   

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