分子筛凝胶浓缩新城疫病毒疫苗的研究

本文采用新型分了筛凝胶作为浓缩剂对新城疫毒感染鸡胚的尿囊进行了浓缩实验,结果表明,该浓缩胶可使新城疫病毒浓缩９６．２４倍,病毒的损失量为８．６５％,用浓缩胶浓缩新城疫毒后制成灭活苗,浓缩苗进行鸡的免疫实验,以研究浓缩疫苗的免疫效果,浓缩新城疫抗原后灭活苗免疫后８天抗体水平迅速上升,ＨＩ为５．６,并持续上升,均高于对照组,说明浓缩疫苗可以使鸡产生较高的抗体水平。     

新城疫浓缩灭活疫苗的初步研究

以10^3.0、10^4.0、10^5.0 EID503个不同剂量接种非免疫鸡胚,收获鸡胚液,病毒含量测定结果显示,以10^3.0-10^4.0～EID50剂量接种的鸡胚收获的抗原含量高。用该优化方法繁殖了一批新城疫抗原,采用截留分子量为100kD的浓缩滤膜对新城疫抗原进行浓缩,对不同浓缩倍数的新城疫抗原制备疫苗进行了免疫效力试验。结果表明,以新城疫3倍浓缩抗原制备疫苗,以5μL剂量（现有相关产品效力检验的1／4剂量）免疫SPF鸡,即可达到现有同类产品的效力检验质量标准,高抗体水平至少可以维持35d。本研究为进一步研制新城疫灭活浓缩疫苗用于低剂量免疫肉鸡提供了基础。     

鸽禽Ⅰ型副粘病毒油佐剂灭活苗对雏鸡免疫效果评价

用鸽Ａ／ＰＭＶ－１油佐剂灭活苗与ＮＤＶ油佐剂灭活苗分别免疫雏鸡,免疫后２１ｄ抗体水平达到峰值,免疫后４２ｄ用新城疫强毒对两种疫苗免疫鸡分别进行攻击,鸽Ａ／ＰＭＶ－１油佐剂灭活苗免疫组保护率为７３．３３％,ＮＤＶ油佐剂灭活苗免疫组保护率为９９．６７％。     

鸡新城疫La Sota、传染性支气管炎(H120+W93)二联灭活疫苗的研究

将鸡新城疫La Sota-传染性支气管炎H129二联抗原液、鸡传染性支气管炎W93抗原液分别用甲醛灭活，经浓缩后按一定比例混合，与油佐剂乳化制成二联灭活疫苗，对30日龄的雏鸡免疫，每只0．3ml，免疫接种3周后，新城疫病毒的HI抗体平均达9．7log2，免疫鸡只耐受呼吸道型、嗜肾型传染性支气管炎强毒攻击，保护率均达到90％，疫苗使用安全。     

鸽新城疫病毒分离株的部分生物学特性鉴定及疫苗免疫试验

从暴发疑似鸽新城疫的某赛鸽场分离到1株病毒，通过血凝（HA)试验、血凝抑制（HI）试验及鸡胚中和试验初步鉴定为鸽新城疫病毒，进而进行了鸡胚半数感染量（EID50）、鸡胚平均死亡时间（MDT）测定和对不同动物红细胞的凝集试验，证明该分离株属新城疫强毒力毒株，将该毒株经鸡胚尿囊液增殖后用甲醛灭活，制成油佐剂来活苗，对鸽免疫后检测其血清抗体水平并进行攻毒试验，结果在免疫后21d抗体达到高峰，攻毒试验表明油佐剂灭活苗对鸽新城疫病毒感染有较强的保护力。     

两种新城疫灭活疫苗免疫原性比较

新城疫作为家禽养殖业危害最大的疫病之一,近些年来常发生免疫失败的现象,究其原因,由于免疫压力的增大和变异株的增多,使疫苗的免疫效果受到极大的挑战,因此选择合适的病毒株制备疫苗对免疫效果具有重要的意义。论文通过测定抗体水平比较新城疫基因Ⅶ型A-Ⅶ株和传统基因Ⅱ型La Sota株油乳剂灭活疫苗对鸡只免疫效价的影响,通过攻毒后的保护、排毒情况及病毒载量的研究,综合比较了2种毒株的免疫原性。通过本试验发现,利用基因Ⅶ型A-Ⅶ株灭活苗与基因Ⅱ型La Sota株灭活苗免疫SPF鸡后,A-Ⅶ株灭活苗所产生的HI抗体效价明显高于La Sota株灭活苗。而通过基因Ⅶ型YND株和标准强毒F48E9株攻毒试验结果显示,2种疫苗均能100%的保护鸡只不死亡,但A-Ⅶ株比La Sota株灭活苗能够更好地抑制强毒在体内的复制和排毒。由此可见,基因Ⅶ型A-Ⅶ株对不同基因型强毒的抵抗能力优于基因Ⅱ型La Sota株,具有更好的免疫原性,通过本试验可为新城疫的防控选择合适的疫苗提供一定的参考。     

经鸡胚感染的ALV-J对新城疫弱毒疫苗免疫的抑制作用及疫苗株对病毒载量的影响

为了解经鸡胚感染携带J亚群禽白血病病毒(ALV-J)的雏鸡体内ALV-J对新城疫(ND)弱毒疫苗(La Sota株)免疫的抑制作用以及疫苗免疫后增强ALV-J对雏鸡致病作用的可能性,随机选择50个SPF鸡胚经卵黄囊接种模拟ALV-J感染,同时选取等量SPF鸡胚以相同方式接种PBS作为对照。出雏后于接毒组和对照组各取20只SPF鸡在7日龄时免疫ND弱毒疫苗(La Sota株)。2～6周龄时,记录各组鸡的体重和免疫器官指数,并对雏鸡的NDV抗体水平和血液ALV-J病毒载量进行动态检测。结果显示,感染ALV-J的SPF鸡5、6周龄时体重显著低于PBS对照组(P0.05),而感染ALV-J再免疫新城疫弱毒疫苗后SPF鸡体重进一步降低(P0.05);与PBS对照组相比,6周龄时感染ALV-J的SPF雏鸡胸腺萎缩和脾脏肿大(P0.05),免疫新城疫弱毒疫苗后胸腺和脾脏损伤加剧(P0.05);3、4周龄时感染ALV-J再免疫ND弱毒疫苗组的雏鸡NDV抗体水平极显著低于仅免疫ND弱毒疫苗组(P0.01);4周龄时免疫弱毒疫苗后的SPF鸡血液中ALV-J病毒载量高于未免疫组(P0.01)。研究表明,感染ALV-J的雏鸡在免疫ND弱毒疫苗(La Sota株)后增强了ALV-J对SPF雏鸡的致病作用,提示净化种源的重要性。     

不同禽流感病毒含量的新-流二联灭活疫苗免疫SPF鸡后抗体水平的监测

将未浓缩的新城疫抗原分别与未浓缩的、浓缩3倍、浓缩6倍的禽流感抗原混合,并制备成三组鸡新城疫、禽流感（H9N2 HP株）二联灭活疫苗（简称新-流二联灭活疫苗）,分别免疫21日龄SPF鸡,每羽0.3 mL,同时设置未免疫的空白对照组,免疫组与对照组均在免疫前及免疫后7、14、21、28、35 d进行采血,检测新城疫和禽流感抗体。结果发现,各免疫组在免后不同日龄的新城疫抗体基本一致,禽流感病毒抗原浓缩倍数越高（即禽流感病毒含量越高）的新-流二联灭活疫苗,免后14、21 d的抗体也越高;从免后21 d开始,各免疫组的禽流感抗体水平差异逐渐减小,免疫后禽流感抗体水平的高低可以反映该疫苗的免疫效果。试验结果表明,该疫苗可以通过浓缩提高抗原病毒含量的方法来提高免后早期抗体水平,取得良好的早期免疫效果。     

禽流感灭活疫苗的研制与疫苗免疫试验

将分离到的３个不同毒株禽流感病毒分别接种９～１０日龄鸡胚,收获尿囊液,经甲醛灭活,配以油佐剂制成油乳剂灭活疫苗,接种５周龄的非禽流感疫苗免疫鸡,注苗后无不良反应。免疫后每周采血一次,测ＨＩ抗体,结果表明免疫后７天抗体普遍上升１～２个滴度,１４天平均抗体水平在７．５ｌｏｇ２以上,２１天抗体水平在８～９ｌｏｇ２以上,免疫后２１天攻毒,免疫组鸡无临床症床和死亡,对照组出现临床症状,但未死亡,攻毒一周后,     

鸵鸟新城疫免疫程序的制定及现场应用试验

本文通过对鸵鸟新城疫病毒母源抗体及疫苗免疫后抗体消长动态的检测，制定出了鸵鸟新城疫的免疫程序：首免：21日龄，新城疫病毒灭活疫苗，0．5—1．0mL／只，肌注；二免：55—60日龄，新城疫病毒灭活疫苗，1．5～2．0mL／只，肌注；三免：100日龄，新城疫病毒灭活疫苗，3．0～5．0mL／只，肌注；以后每4—5个月加强免疫接种一次，至出售；种鸟免疫接种新城疫病毒油乳剂灭活疫苗，7．0～10．0mL／只。肌注，原则上每6～7个月加强一次，但要避开产蛋高峰期。该免疫程序经现场应用3年，免疫效果良好，至今未见该病的发生流行。     

Immune response to oil-emulsion vaccines with single or mixed antigens of Newcastle disease, avian influenza, and infectious bronchitis

Inactivated Newcastle disease virus (NDV), avian influenza virus (AIV), and infectious bronchitis virus (IBV) antigens were evaluated for immunological efficacy in monovalent and polyvalent vaccines. Vaccinated broilers were bled for hemagglutination-inhibition (HI) tests at 1- or 2-week intervals. Half of the chickens were challenged with the Largo isolate of velogenic viscerotropic (VV) NDV at 8 weeks post-vaccination, and the remainder were challenged with the Massachusetts 41 strain IBV at 9 weeks post-vaccination. Newcastle disease HI titers were reduced significantly (P less than 0.05) from those of monovalent control vaccine groups when IBV antigen was emulsified in mixtures with low (1-3x) concentrated NDV or NDV and AIV antigens. Avian influenza HI titers were significantly (P less than 0.05) lower than those of the control monovalent groups when highly concentrated NDV was part of the polyvalent vaccine. Infectious bronchitis HI titers were higher than those of control monovalent groups in 13 of 15 vaccine groups when IBV antigen was in polyvalent formulations. VV NDV challenge killed all non-NDV vaccinates and induced increased HI titers in NDV vaccinates but no morbidity or mortality. Sixty of 80 IBV vaccinates experienced a fourfold or greater HI titer increase following challenge. All non-IBV vaccinates seroconverted at 1 week post-challenge.     

NDV地方分离株与La Sota株抗原交叉性研究

用新城疫弱毒疫苗株La Sota阳性血清测定NDVMM，NDVLD，NDV-NH3株新城疫病毒地方分离株和标准株La Sota，F48E9的HI效价，以La Sota阳性血清对La Sota疫苗株的HI效价为参照，分析NDV地方分离株与疫苗株抗原交叉性。结果表明，NDV-MM，NDV-LD 2个野毒株HI效价与NDV-LD HI效价相近，但比La Sota HI效价低2．3个～2．7个滴度；NDV-NH与F48E9 HI效价相近，比La SotaHI效价低4．2个～4．3个滴度，提示以上3个野毒株与疫苗株之间的抗原相关性差异较大。动物免疫保护试验结果表明，经La Sota免疫（HI效价〉2^5）后攻毒保护率为80％-100％。     

鸡γ-干扰素联合新城疫活疫苗对肉鸡免疫效果的研究

选用350只1日龄罗氏308商品肉鸡,比较不同剂量的鸡γ-干扰素(ChIFN-γ)在新城疫活疫苗免疫前、后使用以及与疫苗同时使用对淋巴细胞刺激指数、巨噬细胞吞噬指数以及鸡新城疫HI抗体滴度的影响。结果显示:各试验组淋巴细胞刺激指数(SI)均高于空白对照组,表现差异显著(p<0.05);与疫苗对照组相比,疫苗免疫后给药组SI优于免疫前给药组和同时给药组,其中两次免疫后给药组好于一次免疫后给药组,500IU/羽的使用剂量优于100IU/羽;ChIFN-γ在免疫的不同时期使用均能有效提高巨噬细胞吞噬指数;两次免疫后给药组较疫苗对照组能明显提高28日龄以后新城疫抗体滴度,表现差异显著(P<0.05);一次免疫后给药组和免疫前给药各组的新城疫抗体滴度及变化趋势与疫苗对照组接近;但同时给药组各日龄段的新城疫抗体滴度都明显低于疫苗对照组。本试验结果显示ChIFN-γ联合新城疫活疫苗使用有助于提高疫苗免疫效果,其使用最佳时机为新城疫活疫苗免疫后使用,使用剂量为500IU/羽。     

口服重组鸡α-干扰素对鸡新城疫病毒感染和疫苗免疫的影响

通过点眼、滴鼻的方式使SPF鸡感染新城疫La Sota株,感染8 h后在饮水中添加1000 U/mL重组鸡α-干扰素,每只鸡每天饮用干扰素剂量为20000 U,分别饮用不同时间。于感染后第7天采集气管组织,制备病理切片。结果显示,连续3 d以上饮用重组鸡α-干扰素的试验鸡,其气管的病理损伤可得到明显改善;检测饮用重组鸡α-干扰素后试验鸡的新城疫抗体效价,结果表明口服高剂量的干扰素可明显下调新城疫抗体的滴度。     

鸡新城疫病毒抗原超滤技术研究

应用分子筛过滤技术超滤浓缩鸡新城疫病毒,并就ＮＤＶ抗原量对鸡免疫应答的和了动态研究,试验结果显示,将ＮＤＶ对外开放尿囊毒浓缩４倍体积,ＨＡ效价提高了２个滴度,病毒回收率达１００％;病毒活性亦未发生改变。免疫１１天后,ＮＤ浓缩苗和ＮＤ－ＩＢＤ二联苗组鸡的ＮＤ－ＨＩ抗体水平远远高于免疫对照组,差异极显著。结果表明,所建超滤技术适用于ＮＤＶ怕的浓缩应用;适量增另ＮＤＶ怕量能够加快鸡的体液免疫应答,增强鸡     

鸡传染性支气管炎病毒与新城疫病毒增殖作用及免疫干扰的研究

试验旨在观察鸡传染性支气管炎病毒（infectious bronchitis virus,IBV）和鸡新城疫病毒（newcastle disease virus,NDV）之间的增殖干扰现象,分析在免疫过程中两种疫苗存在的免疫干扰,为确定疫苗的免疫程序提供依据。采用完全随机试验设计,选取10日龄鸡胚尿囊腔接种不同浓度的IBV、NDV以及不同浓度混合的IBV和NDV,收集尿囊液测定其血凝效价（HA）;用不同浓度的IBV、NDV以及不同浓度混合的IBV和NDV分别免疫BALB/c小鼠及SPF雏鸡,收集血清,间接酶联免疫吸附法（ELISA）和血凝抑制（HI）试验测定IBV和NDV的抗体效价及抑制效价。结果表明,同胚培养时,无论先接种IBV后接种NDV还是先接种NDV后接种IBV或IBV和NDV同时接种,IBV对NDV均有干扰作用,而NDV对IBV没有干扰作用;接种IBV和NDV的小鼠,其产生IBV和NDV的抗体效价均低于单独免疫组,免疫的次序及免疫间隔时间对IBV和NDV的抗体效价均有影响,IBV对NDV的免疫效果具有较大的干扰作用。不同针混合免疫方式能提高IBV和NDV的抗体效价;接种IBV和NDV的雏鸡,免疫次序及免疫相隔时间对IBV和NDV的抗体效价均有影响,IBV对NDV的免疫效果具有较大的干扰作用;雏鸡和小鼠免疫血清HI试验数据表明,免疫次序及免疫间隔时间对IBV和NDV抗体的产生均有影响,但对NDV抗体的产生影响更明显,随着免疫间隔时间的增加,IBV和NDV的抗体水平呈增加趋势,雏鸡比小鼠更能敏感地反映出IBV对NDV的免疫干扰作用。混合注射时IBV和NDV的抗体水平均降低,IBV对NDV的免疫效果有干扰作用。因此,在同胚培养、小鼠及雏鸡的免疫中,IBV对NDV有干扰作用,而NDV对IBV无干扰作用。混合接种时IBV和NDV抗体效价均下降,IBV对NDV的免疫效果有干扰作用。免疫次序及免疫间隔时间对IBV和NDV抗体的产生均有影响,但随着免疫间隔的增加,IBV和NDV的抗体水平呈增加趋势。     

Study on the Effect of Infectious Bronchitis Virus and Newcastle Disease Virus on Proliferation and Immune Interference

This experiment aimed to investigate the proliferation interference effects of the infectious bronchitis virus (IBV) and Newcastle disease virus (NDV),analyze the immune interference of two vaccines in the immune process,and provide a basis for determining vaccine immune program.This experiment was in a complete randomized design,10-day-old allantoic cavity of the chick embryo was inoculated with different concentrations of IBV and NDV and with a mixture of different concentrations of IBV and NDV,and then the allantoic fluid was collected for determination of the titer of hemagglutination (HA).Furthermore,BALB/c mice and SPF chicken were immunized with different concentrations of IBV and NDV and also with the mixed IBV and NDV with different concentrations,the blood of mice and chicken were collected,and antibody titer and inhibitory titer of IBV and NDV were determined by indirect enzyme linked immunosorbent assay (ELISA) and hemagglutination inhibition (HI) test.Experimental results showed that in the homeomorphic cultivation research,whether IBV and NDV were inoculated in a different order or inoculated at the same time,the inoculation of IBV behaved interference to the NDV,while the inoculation of NDV had no interference effects to IBV;Mice were inoculated with IBV and NDV,IBV and NDV antibody titers were lower than single immunized group,immune procedures and immune intervals often had effect on the titer of IBV and NDV antibody,IBV had interference on the immune effect of NDV,different needle mixed immunization can improve the antibody titer of IBV and NDV.In the group of SPF chicken inoculated with IBV and NDV,the order of the inoculation and the immune interval had effect on the titer of IBV and NDV antibody,IBV had a interference on the immune effect of NDV;In the immune serum inhibitory test,the data showed that the IBV and NDV antibody production were affected by the immune order of the inoculation and the interval,the effect on the NDV antibody was more obvious,but with the increase of the immune interval,the antibody level of IBV and NDV showed an increasing trend,the chicken was more sensitive than the mice to reflect the immune interference of IBV on NDV.IBVand NDV antibodies titer was also reduced in the groups that was inoculated with the mixed IBV and NDV,IBV had a interference on the immune effect of NDV.In the homeomorphic cultivation research and animal research,IBV behaved interference to the NDV,while NDV had no interference effects to IBV.IBV and NDV antibody titers decreased when mixed immunization,IBV had a interference on the immune effect of NDV.The order of the inoculation and the immune interval had effect on the antibody titer of IBV and NDV,but with the increase of the immune interval,the antibody level of IBV and NDV showed an increasing trend.     

Generation of a genotype VII Newcastle disease virus vaccine candidate with high yield in embryonated chicken eggs

To generate a genotype VII Newcastle disease virus (NDV) vaccine with high yield in embryonated chicken eggs, we selected genotype VII NDV strain JS5/05, which possesses a high virus titer in embryos as the parental virus. Using reverse genetics, we generated a genetically tagged derivative (NDV/AI4) of JS5/05 by changing the amino acid sequence of the cleavage site of the F0 protein. Pathogenicity tests showed that NDV/AI4 was completely avirulent. NDV/AI4 was genetically stable and replicated efficiently during 10 consecutive passages in embryos. More importantly, serologic assays showed that oil-emulsion NDV/AI4 induced higher hemagglutination inhibition (HI) titers against the prevalent virus than oil-emulsion LaSota vaccine in chickens and geese. Moreover, NDV/AI4-induced HI titers rose faster than those elicited by LaSota in chickens. Both NDV/AI4 and LaSota provided protection against clinical disease and mortality after the challenge with the genotype VII NDV strain JS3/05. However, NDV/AI4 significantly reduced virus shedding from the vaccinated birds compared to LaSota. Taken together, these results suggest that NDV/AI4 can provide better protection than LaSota and is a promising vaccine candidate against genotype VII NDV.     

进口法国种鸽新城疫病毒的分离和鉴定

用鸡成纤维细胞和鸡胚从30只进口法国种鸽中分离出一株病毒,细胞培养物的HA效价为3log2,尿囊液的HA效价为4log2,新城疫阳性血清能抑制这种血凝作用,HI效价均为7log2,禽流感阳性血清不能抑制这种血凝作用.通过透射电镜观察、毒力测定等最终确认,分离出的病毒为新城疫病毒.     

重组鸡白细胞介素-6/2融合蛋白对新城疫(LaSota株)活疫苗免疫增强作用研究

为探究重组鸡白细胞介素-6/2融合蛋白(rChIL-6-Linker-ChIL-2,重组融合蛋白)对新城疫病毒(NDV)活疫苗(LaSota株)的免疫增强作用,本研究将90只SPF鸡随机分为6组,分别为PBS对照组、NDV弱毒苗对照组、rChIL-6-Linker-ChIL-2免疫增强组、rChIL-6蛋白免疫增强组、rChIL-2蛋白免疫增强组及rChIL-6+rChIL-2混合蛋白免疫增强组,将鸡白细胞介素重组融合蛋白水剂与LaSota株联合接种于SPF鸡,分别采用MTS法、流式细胞术、ELISA和HA/HI法检测接种前后不同时间各组鸡外周血及脾淋巴细胞增殖活性、鸡外周血中CD3+CD4+/CD3+CD8+T淋巴细胞的百分含量、血清中Th1/Th2型细胞因子表达水平及免疫抗体水平等指标。结果显示,接种后7～21d时,与NDV弱毒苗对照组相比,同时接种重组融合蛋白组鸡淋巴细胞增殖活性、外周血CD3+CD4+/CD3+CD8+T淋巴细胞的百分含量比值及血清中重组鸡IL-4蛋白(rChIL-4)、ChIL-6、ChIL-2、重组鸡IFN-α蛋白(ChIFN-α)、ChIFN-γTh1/Th2型细胞因子表达水平明显提升;HI免疫抗体较NDV弱毒苗对照组提高了1.0～1.9个滴度,较单一rChIL-6、rChIL-2对照组分别提高了0.2～0.7、0.2～1.1个抗体滴度。综上所述,rChIL-6-Lin-ker-ChIL-2融合蛋白对NDV(LaSota株)活疫苗在鸡体内具有明显的免疫增强效果。