1株鸡传染性支气管炎病毒变异株的分子特征和抗原性分析

从山东省发病商品鸡群分离鉴定了1株鸡传染性支气管炎病毒,命名为CK/CH/SD09/005.S1基因序列分析发现,该株和同期分离的16个IBV流行株与疫苗株H120和491同源性分别为65.2％和66.0％.BLAST发现,CK/CH/SD09/005株仅与GenBank中3个广东分离株同源性较高(98.6％～98.8％),并形成独立的进化群.分别以H120和491为参考株,除了广泛的点突变,CK/CH/SD09/005 S1基因在多个位点发生了插入和缺失,CK/CH/SD09/005 N基因仅发生了点突变,没有基因插入和缺失；M基因除了发生点突变之外,分别在16～18和7～18位发生了碱基插入.鸡胚中和试验结果显示,CK/CH/SD09/005与H120和491均有交叉中和性,抗原相关性分别为0.18和0.09,应属于Mass和793/B之外新的血清型.结果表明,IBV S1基因可同时通过点突变、插入和缺失产生变异株,增加了免疫预防的难度.     

鸡肾型传染性支气管炎病毒组织嗜性的研究

本研究用鸡肾型传染性支气管炎病毒 (肾型 IBV) C90 0 1株人工感染 14日龄 SPF鸡 ,于接种后定期采集病鸡的各组织器官制备成石蜡切片 ,用建立的检测石蜡切片中肾型 IB病毒的免疫酶组化染色技术 ,对人工感染肾型传染性支气管炎 (肾型 IB)鸡发病后病毒的组织器官亲嗜性和动态分布规律进行了研究。结果表明 ,肾型 IBV在胞浆内复制 ,主要亲嗜气管黏膜的上皮细胞和固有层腺体细胞、肺各级支气管上皮细胞以及肺房和呼吸性毛细管上皮细胞、气囊上皮细胞、肾和输尿管上皮细胞、消化道上皮和固有层腺体细胞、肝小叶间胆管上皮细胞、胰腺导管上皮细胞和腺泡上皮细胞、法氏囊淋巴滤泡髓质区淋巴细胞和网状细胞、胸腺小叶髓质区淋巴细胞和网状细胞、脾小体淋巴细胞、盲肠扁桃体弥散性淋巴组织的淋巴细胞以及心肌细胞 ,病毒出现的先后顺序为气管、肺脏、肾脏、输尿管 ,消化道、法氏囊、肝脏、胰脏、胸腺和气囊 ,盲肠扁桃体 ,脾脏 ,心肌。病毒在肾脏和输尿管持续 2 0天 ,气管为 13天 ,消化道和法氏囊为 11天 ,肝脏、胰脏和肺为 10天 ,胸腺为 6天 ,气囊为 5天 ,盲肠扁桃体、脾脏、心肌呈一过性感染     

肾型传染性支气管炎病毒对鸡嘌呤代谢的影响研究

用T株肾型传染性支气管炎病毒(IBV)人工感染14日龄非免疫土种鸡建立感染模型,于攻毒前、攻毒后48 h、72 h、96 h、120 h 采集血样,测定血浆黄嘌呤氧化酶(xanthine oxidase, XOD)活性,探索鸡嘌呤代谢变化与肾型IBV致病机理之间的关系.结果表明,与攻毒前相比较, 攻毒后48 h和72 h血浆XOD活性明显增强, 差异显著(P<0.01,P<0.05).结果提示,XOD活性升高引起的嘌呤代谢紊乱可能是鸡肾型IB的病理机制之一.     

4株鸡肾型IBV陕西分离株3种主要结构蛋白基因的遗传变异分析

采用RT—PCR方法对近年来本实验室分离的4株肾型IBV陕西分离株的纤突蛋白S1基因、膜蛋白基因（M）和核蛋白基因（N）分别进行扩增,测序后进行遗传变异分析。结果显示：与肾型疫苗株w93相比,各分离株S1基因均存在广泛的点突变,并且都存在基因插入现象,分离株之间氨基酸同源性为75．8％～99．4％;M基因除了存在点突变外,W09和WNl2在其5’端还存在9个核苷酸的缺失,分离株之间氨基酸同源性为91．0％～99．6％;N基N无插入和缺失,但存在基因点突变,分离株之间氨基酸同源性为99．3％～99．5％。4株IBV分离株在S1、M和N基因氨基酸系统进化树上分属于不同的进化群,且都与较早的肾型IBV陕西分离株w118遗传距离较远。结果表明,4株鸡肾型IBV流行毒株的s1、M和N基因均存在不同程度变异,这可能是免疫鸡群肾型鸡传染性支气管炎长期流行的主要原因．     

Evaluation of the antigen relatedness and efficacy of a single vaccination with different infectious bronchitis virus strains against a challenge with Malaysian variant and QX-like IBV strains

BackgroundThe predominant infectious bronchitis virus (IBV) strains detected in chickens in Malaysia are the Malaysian variant (MV) and QX-like, which are associated with respiratory distress, nephropathy, and high mortality. On the other hand, the antigenic relatedness and efficacy of IBV vaccines against these 2 field IBV strains are not well characterized.ObjectivesThis study aimed to determine the antigen relatedness and efficacy of different IB vaccine strains against a challenge with MV and QX-like strains.MethodsThe antigen relatedness and the ability of different IB vaccine strains in conferring protection against MV and QX-like were assessed based on the clinical signs, macroscopic lesions, and ciliary activity.ResultsThe MV strain IBS037A/2014 showed minor antigenic subtype differences with the vaccine virus Mass H120 and 4/91 strains but showed major antigenic subtype differences with the K2 strain. The Malaysian QX-like strain IBS130/2015 showed major antigenic subtype differences with the MV strain IBS037A/2014 and the vaccine strains except for K2. Chickens vaccinated once with Mass (H120) or with non-Mass (4/91 and K2) developed antibody responses with the highest antibody titer detected in the groups vaccinated with H120 and 4/91. The mean ciliary activities of the vaccinated chickens were between 56 to 59% and 48 to 52% in chickens challenged with IBS037A/2014 and IBS130/2015, respectively. The vaccinated and challenged birds showed mild to severe lesions in the lungs and kidneys.ConclusionsDespite the minor antigenic subtype differences, a single inoculation with Mass or non-Mass vaccines could not protect against the MV IBS037A/2014 and QX-like IBS130/2015.     

鸡肾型传染性支气管炎病毒的分离鉴定

从安徽省巢湖地区鸡群中出现的以肾肿大为主要特征的呼吸道疾病的病例中分离到1株病毒,易感雏鸡,病死鸡出现肾肿大、苍白呈花斑状、大量尿酸盐沉积;鸡胚连续盲传至第5代时开始出现死亡和侏儒胚.电镜观察可见80～120nm的病毒颗粒.分离病毒在鸡胚上可干扰新城疫病毒clone-30株的增殖.上述试验证实所分离的病毒为鸡肾型传染性支气管炎病毒,暂定名为NIBV-AH99.     

Evaluation of protection conferred by a vaccination program based on the H120 and CR88 commercial vaccines against a field variant of avian infectious bronchitis virus

Due to serotype variations among different avian infectious bronchitis viruses isolated in Tunisia since 2000, protection of chicks, especially broiler flocks, with Mass H120 vaccine often fails. Therefore, association of CR88 (793B type) with H120 vaccines was used for better response. Challenge experiments were then conducted to evaluate tracheal and renal cross-protection in chickens immunized via nasal and eye drops. Conferred protection was measured by clinical signs and macroscopic lesions observed, based on scores attributed according to their severities. The results showed a low protection conferred by H120 alone, as vaccination did not reduce tracheal and kidney lesions (70% scored as 3) after TN20/00 virus challenge, which also led to 10% mortality. Conversely, the challenge results indicated that the combination of the 2 strains (H120/CR88) allow high protection. Based on the results of the challenge experiments, a vaccination protocol coupling CR88 to H120 was applied for industrial broiler flocks. Clinical observations and serological results confirmed that association of heterologous serotypes (H120 and CR88 vaccines) increased the levels of protection against infectious bronchitis viruses compared with the H120 vaccine given alone.     

Detection and isolation of QX-like infectious bronchitis virus in Japan

The antigenic variant QX-like infectious bronchitis virus (IBV) is endemic in several countries. In Japan, the QX-like genotype is classified as the JP-III genotype based on the partial S1 gene and as the GI-19 genotype based on the complete S1 gene. This study showed that QX-like IBVs and JP-III IBVs can be identified based on the amino acid polymorphism of the S1 glycoprotein. Furthermore, genetic analysis of several IBV field strains detected in commercial broiler farms across the Kyushu area in 2020 revealed Japanese QX-like IBVs, which are highly homologous to the QX-like IBVs recently detected in China and South Korea. Herein, QX-like IBV field strains were isolated for evaluating commercial vaccine efficacy in our future studies.     

禽传染性支气管炎病毒S基因的研究进展

作为严重危害养禽业的禽传染性支气管炎病毒(IBV),正受到兽医界的普遍关注。文章就人们在分子生物学领域对IBV S基因的结构特征、免疫活性、与病毒血清的关系、基因工程疫苗等方面的研究概况作了综述,并且根据病毒与热休克蛋白(HSPS)之阃相互作用,设想使IBV的S基因与HSPS结合,开发出一种新型高效的IBV疫苗。     

鸡传染性支气管炎病毒地方流行株的分离与鉴定

从山西各地区疑似鸡传染性支气管炎(IB)的病料中,分离到5株鸡传染性支气管炎病毒(IBV)分离株,并对分离病毒进行了病毒形态观察、对鸡新城疫病毒(NDV)的干扰、鸡胚致病性试验、动物回归试验、血凝特性试验、病毒理化特性测定等生物特性鉴定及IBV N基因特异性片段的检测.电镜观察,可见直径为60～120 am,有囊膜及纤突呈冠状排列的病毒粒子;对NDV有明显的干扰作用;分离株的传代物均有明显的致鸡胚矮小化作用;动物回归感染死亡鸡肾脏病变明显,表现肾脏肿大、花斑肾现象,输尿管内充塞大量尿酸盐;无直接血凝性,经1%胰酶处理后可凝集鸡红细胞;分离株对乙醚和氯仿敏感;采用反转录-聚合酶链式反应(RT-PCR)对分离毒株进行扩增,结果均扩增出特异N基因核酸片段.     

Avian infectious bronchitis virus in Africa: a review

Infectious bronchitis virus (IBV) is worldwide in distribution, highly infectious, and extremely difficult to control because it has extensive genetic diversity, a short generation time, and a high mutation rate. IBV is a Gammacoronavirus, single-stranded, and positive-sense RNA virus. Avian infectious bronchitis is well studied in European countries with identification of a large number of IBV variants, whereas in African countries epidemiological and scientific data are poor and not updated. However, previous studies reported that an IBV variant continues to appear regularly in Africa, as currently described in Morocco. No cross-protection between IBV strains was reported, some being unique to a particular country, others having a more general distribution. This review aims to provide a general overview on IB disease distribution in African countries and an update on the available studies of IBV variants in each country.     

用冷适应的方法致弱鸡肾型传染性支气管炎病毒

用冷适应的方法 (病毒经囊液接种鸡胚后于 32℃孵化 48h) ,将已鉴定的北京地区鸡肾型传染性支气管炎病毒 (IBV)分离株 Tu,Da,Xi和 Hu分别通过鸡胚传代减毒致弱 ,在一定代次时接种敏感鸡作毒力测定试验 ,结果表明 ,Tu株在传至 46代时 ,Xi株在传至 5 1代时对雏鸡的毒性已大为降低 ,并且分别回归 SPF雏鸡 5代和 3代后不出现返强现象。毒价测定 Tu46和 Xi51 的 EID50 值分别为 10 - 6.3 6/ 0 .2 m l和 10 - 6.70 / 0 .2 m l,而且 Tu株出现稳定增高的趋势。它抵抗同源强毒攻击的最小免疫剂量为 10 - 2 × 0 .5 m l。此外 ,对弱毒株免疫后的雏鸡用标准强毒株Gray攻击以衡量其免疫原性 ,结果 Tu46具有 90 %的保护率。间接 EL ISA对免疫后的抗体水平检测结果反映 ,Tu46免疫鸡体内血清抗体的消长呈规律性变化 ,并在免疫后 2 0天出现最高峰。综合结果表明 ,作者培育的 IBV- Tu46株具有对雏鸡安全、毒价高及较好的免疫原性的特点 ,有希望成为供生产使用的疫苗。     

传染性支气管炎病毒TY1株结构蛋白基因部分片段的表达

根据已报道的传染性支气管炎病毒S基因序列设计了1对引物，利用从传染性支气管炎病毒TY1株中提取的RNA，经PCR扩增获得了300bp的产物；序列测定与分析表明，所扩增产物是传染性支气管炎病毒结构蛋白基因的部分片段。将扩增片段插入pET32a构建表达载体，并于大肠埃希氏菌BL21中进行表达；结果表明，该片段在大肠埃希氏菌中成功表达，产物为30ku、以可溶性形式存在的蛋白。Western—blotting分析表明，该蛋白可与传染性支气管炎病毒TY1株阳性血清发生反应。     

表达传染性支气管炎病毒S1基因重组鸡痘病毒的构建

将鸡传染性支气管炎病毒S1基因插入到鸡痘病毒转移载体pSY681中，获得重组转移载体pSY681。将pSY681-IBVS1转染已感染亲本鸡痘病毒S-FPV-017株的鸡胚成纤维细胞，使其在鸡胚成纤维细胞内与鸡痘病毒基因组发生同源重组，产生表达鸡IBVS1蛋白的重组鸡痘病毒rFPV-IBVS1。在含有X-gal的营养琼脂培养基上进行蓝斑筛选且进一步纯化14代。S1基因的PCR检测表明，获得的含传染性支气管炎病毒S1基因的重组鸡痘病毒能够稳定遗传，间接免疫荧光和Western blot等试验证实该重组病毒在CEF内真实地表达了分子量约为90Ku的具有免疫学活性的IBV S1糖蛋白。     

Pathogenesis of H13 nephropathogenic infectious bronchitis virus

A nephropathogenic Massachusetts strain of infectious bronchitis virus (IBV) designated H13-IBV was isolated from the kidneys of commercial broilers. H13-IBV caused respiratory distress, depression, and diarrhea in specific-pathogen-free chickens. Gross renal lesions included pale coloration, swelling, and urate deposition. Histologic renal changes were interstitial mononuclear cell infiltration and degeneration and necrosis of tubular epithelial cells. Lesions in respiratory tissues included thickening and edema of the air sacs, congestion of the tracheal mucosa, and frothy serous exudate. Histologic tracheal lesions were deciliation, mucous gland distortion, inflammatory cell infiltration, and squamous metaplasia. Clinically, H13-IBV was highly pathogenic in birds infected at 1 day of age and mildly pathogenic in birds infected at 4 weeks of age. Kidney lesions were of marked severity only in birds infected at 1 day of age. Tracheal lesions were similar in severity in both age groups.     

鸡传染性支气管炎病毒广西分离株血清型的分析

应用病毒感染的鸡胚材料免疫新西兰兔的方法制备抗鸡传染性支气管炎病毒(IBV)单因子血清,然后在鸡胚气管环培养(Tracheal organ cultures,TOC)上对广西分离的7个IBV代表性毒株和3个常用疫苗株进行交叉病毒中和试验。结果显示,10个毒株被分为6个血清型。根据试验所得的R值,应用聚类分析法分析了各血清型毒株之间的亲缘关系,显示目前在广西流行的IBV野毒株之间以及其与疫苗株间的抗原性存在很大程度的差异,分属不同的血清型。同时还对IBV基因分型和血清分型之间的关系进行了探讨。     

传染性支气管炎病毒S1蛋白在Vero细胞的表达与分布

将传染性支气管炎病毒（IBV）ZJ971 S1基因亚克隆到绿色荧光蛋白（GFP）表达载体pEGFP—C2中，成功构建重组表达质粒pEGFP—ZJ971-S1。重组质粒在脂质体的介导下转染Vero细胞，借助荧光显微镜在转染后4h观察到S1—GFP融合蛋白的瞬时表达。免疫细胞化学染色（ICC）结果显示，抗ZJ971 S1D蛋白单克隆抗体和鸡抗IBVZJ971全病毒血清特异性识别了S1基因转染细胞，表明S1蛋白在Vero细胞中得到有效表达。荧光显微镜观察和ICC均表明，S1表达蛋白主要分布在转染细胞的胞浆内，而胞核中未见分布，提示IBVS1蛋白内可能存在与病毒装配相关的细胞定位信号。