Production and Characterization of Monoclonal Antibodies to Peste des Petits Ruminants (PPR) Virus

Peste des petits ruminants (PPR) is an acute, febrile viral disease of small ruminants, caused by a virus of the genus Morbillivirus. PPR and rinderpest viruses are antigenically related and need to be differentiated serologically. In the present study, 23 mouse monoclonal antibodies were produced by polyethyleneglycol (PEG)-mediated fusion of sensitized lymphocytes and myeloma cells. Among these, two belong to the IgM class and the remaining 21 to various subclasses of IgG. The MAbs from the IgG class designated 4B6 and 4B11 neutralized PPR virus in vitro. In radioimmunoprecipitation assay, 10 MAbs recognized nucleoprotein, 4 recognized the matrix protein and one each haemagglutinin and phosphoprotein. The remaining 7 MAbs failed to precipitate any defined viral protein. The reactivity pattern of the monoclonal antibodies in indirect ELISA indicated a close antigenic relationship within three Indian PPR (lineage 4) virus isolates and also within two rinderpest vaccine strains. All PPR virus isolates could be distinguished from rinderpest vaccine viruses on the basis of the reactivity pattern of all MAbs and anti-N protein MAbs. A set of six monoclonal antibodies specific to PPR virus could also be identified from the panel. From the panel of MAbs available, two MAbs were selected for diagnostic applications, one each for the detection of antigens and antibodies to PPR virus.     

小反刍兽疫研究进展

小反刍兽疫(PPR)是由小反刍兽疫病毒(PPRV)引起的急性或亚急性传染病,为世界动物卫生组织(OIE)法定报告的动物疫病,易感动物以山羊、绵羊等小反刍动物为主.目前,小反刍兽疫主要流行于西非、中非、中东、阿拉伯半岛及南亚等地区.敏感特异的检测方法和高效的预防性疫苗将为该病的防控奠定良好的基础.论文对小反刍兽疫全球流行现状、诊断技术及疫苗研究进展进行了综述.     

Antibody seroprevalences against Peste des Petits Ruminants (PPR) virus in sheep and goats in Sudan

Counter immnuo-electrophoresis (CIEP) and Competitive ELISA (C-ELISA) tests were employed for seroprevalence of Peste des Petits Ruminants (PPR) infection in Sudan. The result of both tests showed high prevalence of PPRV antibodies in sheep and goats sera collected from six different regions of Sudan. Of the 519 serum samples examined for the presence of PPRV antibodies 307(59.15%) were positive by CIEP while 263(50.67%) were positive by C-ELISA. CIEP technique was shown to be more sensitive than C-ELISA technique for detection of PPRV antibodies (Kappa statistics 0.259). C-ELISA allowed rapid, simple, specific, sensitive and differential sero-diagnosis of PPRV and RPV in sheep, goats and cattle. CIEP is, unlike competitive ELISA, is group-specific test and can not differentiate between PPR and RP infections. Despite its low specificity CIEP can be a useful indicative screening test for PPRV antibodies in flocks that neither been vaccinated nor otherwise exposed to PPR or RP virus. Results obtained suggest that CIEP, like the HI test, could be a useful screening test where it is not possible to use C-ELISA.     

小反刍兽疫研究进展

小反刍兽疫病毒(PPRV)是副黏病毒科(Paramyxoviridae)麻疹病毒属(Morbolivirus)的成员,主要感染山羊、绵羊等小反刍动物,引起一种高度接触性病毒性传染病。小反刍兽疫为一种重大的外来性疾病,2007年在中国西藏自治区日土县首次发生。自2013年末以来中国新疆、青海、甘肃、宁夏、内蒙、湖南、辽宁等地频繁暴发小反兽疫疫情,给中国的畜牧业带来了巨大的损失,引起极大的重视。为更好的分析小反刍兽疫的病原特性及采取有效的防控措施,文章对小反刍兽疫的病原学及疫苗研究进展进行论述。     

小反刍兽疫研究进展

小反刍兽疫是由小反刍兽疫病毒引起的一种重大烈性传染病,主要发生于山羊和绵羊等小反刍兽,在国际上已经得到广泛的重视。本文对小反刍兽疫的病毒病原学、流行病学、临床特征、病理变化以及诊断和疫苗研制等国际上的最新进展进行了全面综述。     

OIE小反刍兽疫标准简介

世界动物卫生组织(OIE)小反刍兽疫(PPR)标准是各国PPR防控和绵羊、山羊等小反刍动物及其产品流通贸易应遵守的规定.通过梳理OIE-PPR标准修订历史沿革,从小反刍动物及其产品进出口贸易要求以及PPR状态、监测、病原灭活等方面介绍了2002、2013和2021年版标准的修订情况、具体条款,以及由此带来的新要求.继而...     

小反刍兽疫研究现状

小反刍兽疫(Peste des petits ruminants,PPR)是由小反刍兽疫病毒(Peste des petits ruminants virus,PPRV)引起的一种主要感染小反刍动物的急性、接触性传染病,发病率、死亡率高.近年来,小反刍兽疫(PPR)呈扩散的趋势,成为重要的跨国动物传染病之一,我国周边国家频繁器发该病.2007年7月25日暴发于西藏自治区日土县的我国首例小反刍尊疫疫情,更是对我国如何做好该病的防控工作提出了新的要求和挑战.为了增强广大兽医工作者和相关人士对本病的认识,文中就小反刍兽疫的病原学、流行病学、临床症状、病理特征以及诊断方法等方面的研究现状进行了综述.     

2018—2019年山东省小反刍兽疫专项流行病学调查

为全面掌握山东省小反刍兽疫的病原分布和免疫效果，按照《山东省动物疫病监测与流行病学调查实施方案》，分别于2018年 和2019年，通过问卷调查结合实验室检测，在全省开展了小反刍兽疫专项流行病学调查。结果显示：2018—2019年山东省小反刍兽疫免疫抗体合格率均在80%以上，达到了国家和省级的要求，抗体水平平稳（χ2=0.003，P=0.956 32，P>0.05）；病原学检测均未发现阳性样品。问卷统计结果显示：疫病方面，目前养羊场以细菌性疾病感染为主，没有发现小反刍兽疫疫情；饲养场（户）基本能够做到调入羊只的隔离、检疫，以及养殖场的定期消毒。结果表明，山东省羊群的小反刍兽疫免疫保护水平较高，防控措施执行较为到位，防控形势比较理想。今后需持续开展小反刍兽疫专项流行病学调查，从而为今后小反刍兽疫免疫政策的制定和强制免疫退出提供数据支撑。     

新疆小反刍兽疫疫情诊断

2013年12月新疆伊犁州霍城县发生不明山羊疫情,根据临床症状和剖检变化怀疑为小反刍兽疫感染。对3只病死山羊病料、8只患病山羊分泌物棉拭子样品和6只患病山羊血清样品分别进行病原学和血清学检测。利用竞争ELISA试剂盒对6份血清样本进行抗体检测,结果全部为阳性。利用抗原捕获ELISA试剂盒,在11只病羊样品中都检测到小反刍兽疫抗原。利用能特异性检测小反刍兽疫病毒的荧光定量RT-PCR方法,在11只病羊样品中检测到小反刍兽疫病毒核酸。利用特异引物进行PPRV N基因片段RT-PCR反应,从11只病羊样品中检测到PPRV核酸。针对2号样本病原核酸N基因和F基因片段进行序列同源性比较,结果该毒株与西藏流行株序列片段相似性分别为96.5%和97.5%。遗传进化分析,该病原属于谱系4,与巴基斯坦等国流行毒株遗传关系最近。     

Clinical and Para-clinical Findings of a Recent Outbreaks of Peste des Petits Ruminants in Iran

Peste des petits ruminants (PPR) is a highly contagious and infectious viral disease of domestic and wild small ruminants characterized by fever, erosive stomatitis, conjunctivitis, gastroenteritis and pneumonia. Goats are usually more severely affected than sheep. Peste des petits ruminants is caused by a paramyxovirus of the Morbillivirus genus. In March 2004, a flock of sheep in Tehran province with 430 deaths was visited. According to the history taken from the owner, at disease onset most of the deaths were recorded from adult sheep, 3 weeks later lambs (2 weeks to 4 months of age) showed the highest death rate. All animals from 3 months age received rinderpest vaccine 1 month after onset. Many of the lambs died just a few hours after their first sucking of the colostrum from infected mothers. Most of them showed very acute form of disease and died a few hours after onset of clinical signs. In clinical examinations most of the cases showed severe depression, high fever (41 degrees C), anorexia, mocopulurent nasal discharge, erosive and necrotic stomatitis (dental path, hard palate and cheeks), diarrhoea and dehydration. Para-clinical findings including histopathological, serological and haematological examinations also confirmed the presence of PPR in this flock. PPR outbreaks have been frequent in Iran in recent years. Further, we suggest that PPR is not a recent invader of Iran. The main difference in clinical signs between this outbreak and the same in other reports is that goats did not show any obvious signs of PPR. This might be due to the number of the goats (>1% of the flock) and keeping them separate from the sheep. The present article reviews the details of this outbreak in Iran.     

小反刍兽疫诊断及其免疫防制的研究进展

小反刍兽疫(peste des petits ruminants,PPR)是由副黏病毒科麻疹病毒属小反刍兽疫病毒(peste des petits ruminants virus,PPRV)引起的一种急性、烈性、接触性传染病,目前已给中国养羊业造成巨大损失与威胁。作者对PPR的流行病学、诊断方法及疫苗研制进展等方面作一简要综述,以期为该病的防控提供有效的参考。     

小反刍兽疫病毒在自然感染羊体内的病毒分布

为了解小反刍兽疫病毒在自然感染羊体内的分布情况,平行采集临床发病羊的脾脏、肺脏、心脏、肝脏、肾脏、大肠、淋巴结以及眼拭子、鼻拭子、肛门拭子、血清等样品,应用荧光RT-PCR方法对各样品进行平行检测,比较各样品检测Ct值,评估病毒分布和各样品中的病毒含量,结果显示,所有样品小反刍兽疫病毒核酸均为阳性,其中大肠、肺脏、脾脏和淋巴结的检测Ct值较小,表明小反刍兽疫病毒在自然感染羊体内呈全身分布,但在大肠、肺、脾和淋巴结等组织中的含量较高。     

Utilization of protein-A in immuno-histochemical techniques for detection of Peste des Petits Ruminants (PPR) virus antigens in tissues of experimentally infected goats

This paper constitutes the first record of utilizing the S. aureus protein-A (PA), conjugated to peroxidase enzyme, for the detection of the Peste des Petits Ruminants (PPR) virus antigens in tissues of experimentally infected goats. The goats were experimentally infected with a virulent PPR virus, which was previously isolated from a severe natural disease outbreak in gazelles, during 2002 in Saudi Arabia. The technique is rapid, and has the superiority over the peroxidase –anti-peroxidase (PAP) test in that, inactivation of the indigenous peroxidase in the tissues is not required and that it can be used against a wide range of animal species. An advantage over the other immunolabelled conjugates is that PA attaches specifically to the crystalizable fraction (Fc) of the IgG molecule, thus allowing the antigen binding fraction (Fab) of the molecule, free to interact specifically with the antigen. So, it doesn't actually compete with the antigen for the Fab portion of the IgG molecule. In the present study, PA conjugate detected the PPR virus antigens in various tissues of the experimentally infected goats.     

小反刍兽疫概述

本文就小反刍兽疫的病原学、流行病学、临床诊断、实验室诊断、综合防控等方面进行了全面的概述,以期对小反刍兽疫的防控工作提供帮助。     

内蒙古和西藏自治区野生反刍动物小反刍兽疫监测

为了解小反刍兽疫疫情在野生反刍动物中的流行情况,在风险较高且野生动物集中分布的内蒙古自治区赤峰市、呼伦贝尔市和兴安盟以及西藏自治区日喀则地区、山南地区、阿里地区和那曲地区,平行采集棉拭子样品和血清样品各78份。通过RT-PCR检测小反刍兽疫病毒核酸,同时用竞争ELISA检测反刍野生动物血清中的小反刍兽疫病毒特异性抗体。结果检测样品中未发现阳性样品。说明该批次样品中没有发现野生动物感染小反刍兽疫病毒。研究结果可为小反刍兽疫防控工作提供依据。     

免疫区小反刍兽疫免疫抗体监测与分析

本文报告应用C-ELISA方法监测小反刍兽疫免疫区山羊、绵羊和牦牛PPR免疫抗体的结果。结果显示:检测免疫山羊血清298份,阳性163份,阳性率54.70%;检测免疫绵羊血清588份,阳性140份,阳性率23.81%;累计检测免疫羊(山羊和绵羊)血清886份,阳性303份,阳性率34.20%;检测免疫区非免疫牦牛血清353份,阳性51份,阳性率14.45%。并对试验结果显示的免疫区羊免疫抗体阳性率偏低、山羊和绵羊免疫抗体阳性率差异大及免疫区接触牦牛PPR抗体呈阳性的检测结果进行了分析。     

我国首例小反刍兽疫诊断报告

2007年7月我国西藏发生不明山羊疫情,国家外来动物病诊断中心对当地动物疫病控制中心送检的14只病死山羊病料和一批血清样品分别进行病原学和血清学检测。利用较敏感的小反刍兽疫病毒(PPRV)特异性荧光定量RT-PCR方法,在11只病羊组织中检测到小反刍兽疫病毒核酸。利用次敏感的PPRV普通RT-PCR方法,从8只病羊组织中检测到PPRV核酸。针对1号样本病原核酸N基因和F基因片段进行遗传发生分析,该病原属于4系。利用竞争ELISA试剂盒对送检的13份血清样本进行抗体检测,结果全部阳性。将1号组织样本接种Vero细胞分离病毒,透射电镜观察下,发现了500纳米左右的病毒粒子。对分离毒株进行PCR检测同样证实其为PPRV。     

我国小反刍兽疫疫情现状与防控策略

小反刍兽疫作为重要的跨境动物疫病之一,已经传入我国并广泛流行。对我国养羊业、民生和经济发展造成沉重的打击。为有效防控该病,从小反刍兽疫的病原学、宿主范围,传播特点、传播因素和综合防控的策略等方面进行了概述,重点从制度保障和防控要素方面进行分析,旨在为我国小反刍兽疫的防控提供理论支持。