Avian CD154 enhances humoral and cellular immune responses induced by an adenovirus vector-based vaccine in chickens

Recombinant adenoviral vectors have emerged as an attractive system for veterinary vaccines development. However, for poultry vaccination a very important criterion for an ideal vaccine is its low cost. The objective of this study was to test the ability of chicken CD154 to enhance the immunogenicity of an adenoviral vector-based vaccine against avian influenza virus in order to reduce the amount of antigen required to induce an effective immune response in avian. Chickens were vaccinated with three different doses of adenoviral vectors encoding either HA (AdHA), or HA fused to extracellular domain chicken's CD154 (AdHACD). Hemagglutination inhibition (HI) assay and relative quantification of IFN-γ showed that the adenoviral vector encoding for the chimeric antigen is able to elicit an improved humoral and cellular immune response, which demonstrated that CD154 can be used as a molecular adjuvant allowing to reduce in about 50-fold the amount of adenoviral vector vaccine required to induce an effective immune response.     

鸡传染性支气管炎弱毒苗与灭活苗的免疫效果评价

采用鸡传染性支气管炎弱毒疫苗及肾型和呼吸型毒株的灭活苗对鸡进行了免疫，根据鸡免疫后的抗体水平动态变化和攻毒后鸡肾脏和气管水平上的保护力，比较了传染性支气管炎弱毒苗H120与两个不同致病型毒株灭活苗的免疫效果。试验结果表明，弱毒苗虽可诱导较高水平的抗体，但免疫效果较灭活苗差。     

同胚增殖鸡新城疫病毒和传染性支气管炎病毒的效果观察及免疫应答反应

鸡新城疫病毒（ＮＤＶ）和鸡传染性支气管炎病毒（ＩＢＶ）混合在同一鸡胚中增殖,当ＮＤＶ和ＩＢＶ接种浓度控制在一定范围时,最佳收毒时间选择使ＮＤＶ有足够时间增殖到最佳滴度,且在这一时间内不至于因孵育时间过长而致ＩＢＶ毒力减弱。结果表明ＮＤＶＬａｓｏｔａ株经１０倍稀释分别与４株ＩＢＶ１０００倍稀释液等体积混合后接种,能在同一鸡胚中正常增殖,即９６ｈ收毒,血凝（ＨＡ）方法测定两种病毒的血凝价均能达到最佳滴度,其血凝价不低于各自单独增殖的滴度。４种ＩＢＶ株与ＮＤＶ同胚增殖的ＨＡ滴度进一步证实,在合适的条件下,ＩＢＶ均不对ＮＤＶ的复制产生干扰作用,４种ＩＢＶ的血凝价无明显差异。免疫试验中用同胚增殖两种病毒二联苗接种,鸡体血清中可产生抗两种病毒的ＨＩ抗体,与各自单独接种时的ＨＩ抗体水平几乎一致。本试验中制备的ＩＢ血凝抗原在４℃保存一个月,其血凝活性保持不变。ＩＢＶ微量血凝抑制（ＨＩ）试验特异性测定结果证实,用自制ＩＢＶ血凝抗原进行ＨＩ试验检测鸡ＩＢ阳性血清均能产生稳定的特异性反应,并且无交叉反应。说明ＨＩ试验是检测ＩＢＶ抗体水平的有效可行的方法。     

三黄白术片对人工感染鸡传染性法氏囊病的疗效

３组１６日龄小鸡人工感染以鸡传染性法氏囊病（ＩＢＤ）病毒,４８ｈ后出现临床症状,分别内服三黄白术片,剂量分别为０．３７５ｇ,０．２５ｇ和０．１２５ｇ,每日２次,连服５日,随后的１０日内,治疗组分别死亡１３．３％（４／３０）、１６．７％（５／３０）和４０％（１２／３０）,而未治疗的对照组死亡５３．３％（１６／３０）。在相对增重上,治疗组分别为７３．９％、７０．１％和７１．１％,而未治疗对照组为２５．８％。     

鸡肾型传染性支气管炎病毒分离及鉴定

某鸡场暴发主要以侵害鸡肾脏的疾病,引起肾脏肿大、苍白,肾小管和输尿管有白色尿酸盐沉积,伴有下痢。产蛋鸡产蛋下降,雏鸡的死亡率达25%～90%。从感染鸡分离到1株疑为鸡肾型传染性支气管炎病毒,接种鸡胚,鸡胚出现侏儒化、卷曲等特征性病变。     

Multiple amino acid substitutions are involved in the adaptation of H9N2 avian influenza virus to mice

To explore adaptation of avian influenza virus to mice we previously performed serial lung-to-lung passages of the influenza A/Chicken/Jiangsu/7/2002 (H9N2) strain, resulting in the isolation of a variant influenza strain lethal for mice. We now report that virulence correlates with improved growth characteristics on mammalian cells and extended tissue tropism in vivo. Sequencing of the complete genomes of the wild-type and mouse-adapted viruses revealed 25 amino acid substitutions. Some were found to reiterate known substitutions in human and swine H9N2 influenza isolates. Functions affected include nuclear localization signals and sites of protein and RNA interaction, while others are known determinants of pathogenicity and host specificity such as the viral polymerase PB2 E627K substitution. These observations suggest that enhanced growth characteristics and modified cell tropism may contribute to increased virulence in mice. We conclude that multiple amino acid substitutions are likely to be involved in the adaptation of H9N2 avian influenza virus to mice.     

类人源猪H3N2亚型流感病毒HA,NA遗传进化分析

2007-2008年从吉林省某猪场采集疑似流感发病猪的鼻咽拭子,经病毒分离鉴定获得3株H3N2亚型流感病毒,分别命名为A/swine/Jilin/5/2007（Sw/Jilin/5/07）、A/swine/Jilin/19/2007（Sw/Jilin/19/07）、A/swine/Jilin/37/2008（Sw/Jilin/37/08）。HA进化树分析结果表明：3株H3N2亚型流感病毒属于近代人源病毒谱系;但是在NA进化树中,Sw/Jilin/37/08株与早期人源和近代人源关系密切,暗示它可能是早期人源和近代人源H3N2亚型猪流感病毒之间的过渡毒株,进一步证实猪在流感病毒种间传播过程中充当＂中间宿主＂作用。     

云南松松塔提取物对H22实体瘤小鼠模型的抑瘤作用

研究云南松松塔乙醇提取物(PEA)和碱水提取醇沉物(PED)对H22实体瘤小鼠的抑瘤作用。建立H22实体瘤小鼠模型,随机分组,灌胃给药,1次/d,给药10d。末次给药24h后,取血检测γ干扰素(IFN-γ)、白细胞介素-2(IL-2)、白细胞介素-4(IL-4)和白细胞介素-10(IL-10)含量;剥离肿瘤组织并称重,计算抑瘤率;检测肿瘤组织匀浆中环氧化酶-2(COX-2)和前列腺素E2(PGE2)含量;石蜡包埋HE染色观察肿瘤细胞病理组织学变化。结果显示,PEA和PED各剂量组小鼠平均肿瘤重量较模型组显著减小;最大抑瘤率分别达46.11%和58.05%。PEA和PED各剂量组小鼠外周血中IFN-γ和IL-2含量较模型组显著升高;IL-4和IL-10含量较模型组显著降低。PEA和PED各剂量组小鼠肿瘤组织中COX-2和PGE2含量较模型组显著减少;给药组正常肿瘤组织减少,有出血和坏死,脂肪组织增多。结果表明,PEA和PED可抑制H22实体瘤小鼠的肿瘤生长,其机制与调节Th1/Th2细胞平衡和抑制COX-2与PGE2的表达有关。     

A dynamic, optimal disease control model for foot-and-mouth disease: I. Model description

A dynamic optimization model was developed and used to evaluate alternative foot-and-mouth disease (FMD) control strategies. The model chose daily control strategies of depopulation and vaccination that minimized total regional cost for the entire epidemic duration, given disease dynamics and resource constraints. The disease dynamics and the impacts of control strategies on these dynamics were characterized in a set of difference equations; effects of movement restrictions on the disease dynamics were also considered. The model was applied to a three-county region in the Central Valley of California; the epidemic relationships were parameterized and validated using the information obtained from an FMD simulation model developed for the same region. The optimization model enables more efficient searches for desirable control strategies by considering all strategies simultaneously, providing the simulation model with optimization results to direct it in generating detailed predictions of potential FMD outbreaks.     

神经介素B及其受体NMBR参与抗A型流感病毒H1N1亚型感染的信号通路

NMB/NMBR通过调节A型流感病毒（IAV/H1N1/PR8）感染诱导的细胞因子表达而参与抗IAV的先天性免疫反应。为探究其发挥抗IAV/H1N1感染的信号通路,本文用PR8和WSN毒株分别感染MLE-12细胞和小鼠,用NF-κB抑制剂BAY11-7028单独或联合NMB处理MLE-12细胞,小鼠后腿肌内注射NMB和NMBRA,采用RT-PCR和qRT-PCR分析NMB、NMBR、IL-6、IFN-α和NP基因表达变化,采用Western blot分析NMB、NMBR、P65/p-P65、IκBα和NP蛋白表达的变化。结果显示,BAY11-7028可促使PR8和WSN感染的MLE-12细胞中NMB、NMBR、IL-6和IFN-α基因表达水平均下降和NP基因表达水平上升,并降低NMB、NMBR和p-P65蛋白表达水平和提升IκBα和NP蛋白表达水平。然而,NMB联合BAY 11-7028诱导PR8或WSN感染后的细胞中IL-6和NP表达出现极显著下降和IFN-α显著上升。此外,NMB抑制PR8和WSN感染的小鼠肺组织内p-P65和NP蛋白表达水平和促进IκBα蛋白表达水平;NMBRA联合NMB抵消NMB对PR8或WSN感染后的这些蛋白表达水平的调节作用。综上表明,NMB/NMBR通过调节PR8和WSN感染的MLE-12细胞和小鼠体内的NF-κB信号通路上P65蛋白磷酸化和IκBα的表达,进而影响下游细胞因子IL-6和IFN-α基因的表达,从而发挥抗IAV/H1N1感染的先天性免疫应答反应。