猪外周血单个核细胞cDNA酵母表达文库的构建及与猪瘟病毒E2蛋白相互作用细胞蛋白的筛选

为研究猪瘟病-毒(CSFV)蛋白与宿主细胞蛋白之间的相互作用,本研究通过SMART技术合成猪外周血单个核细胞(PBMC)双链cDNA,以携带与载体pGADT7-Rec重组位点同源序列的特异引物经long-distance PCR扩增双链cDNA.纯化双链cDNA并与载体pGADT7-Rec共转化酵母菌株Y187,经同源重组构建PBMC cDNA酵母表达文库.以CSFV E2蛋白为诱饵进行酵母双杂交筛选,得到阳性克隆根据序列比对分析结果,进一步进行共转化验证.结果显示筛选到17个与CSFV E2蛋白相互作用的宿主细胞蛋白,基因注释(GO)分析表明这些蛋白分别参与免疫、代谢、细胞生长与增殖、生物调节等过程,为研究它们与CSFV E2的相互作用奠定了基础.     

菊苣酸(CA)对LPS诱导的牦牛PBMC细胞炎性因子分泌及表达的影响

为了探究菊苣酸(chioric acid,CA)对脂多糖(lipopolysaccharide,LPS)诱导的牦牛外周血单个核细胞(peripheral blood mononuclear cell,PBMC)炎性相关因子分泌及转录水平的调节作用,用Ficoll法分离牦牛PBMC,体外将PBMC与LPS和CA共同培养,通过CCK-8法筛选LPS最佳刺激浓度,ELISA试剂盒检测CA对炎性相关因子含量的影响,实时荧光定量PCR法检测炎性相关因子mRNA表达情况。结果表明,CCK-8法筛选的LPS最佳致炎质量浓度为1.0 mg/L。与对照组相比,CA处理组显著提高IL-10的含量(P<0.05),LPS处理组显著提高IL-6和IL-1β的含量(P<0.05),极显著提高了IL-8、TNF-a和INF-γ的含量(P<0.01);与LPS处理组相比,CA+LPS处理组IL-6、IL-8、IL-1β、TNF-a和INF-γ的含量均显著降低(P<0.05),但IL-10的含量显著升高(P<0.05)。同时,与对照组相比,CA处理组显著降低IL-1βmRNA表达(P<0.05),显著升高IL-10 mRNA表达(P<0.05),LPS处理组极显著升高IL-6、IL-8、IL-1β、INF-γ和TNF-αmRNA表达(P<0.01);与LPS组相比,CA+LPS处理组IL-6、INF-γ和TNF-αmRNA表达显著降低(P<0.05),IL-8和IL-1βmRNA表达极显著降低(P<0.01),IL-10 mRNA表达显著升高(P<0.05)。上述结果说明,CA可通过调节牦牛PBMC炎性因子的分泌及表达,从而发挥抗炎作用。     

5种免疫增强剂对猪PBMC增殖反应的影响

采用胸腺素、黄芪多糖、人胎盘组织液、人重组白细胞介素 2 ( r IL-2 )及左旋咪唑 ,以不同浓度刺激体外培养不同时间的猪外周血单个核细胞 ( PBMC) ,结果证明这几种佐剂均对猪 PBMC有明显刺激作用 ,且与浓度有依赖关系 ,浓度过高时对其有抑制作用 ,适宜的浓度为 1 0 4倍稀释度。时间因素的影响较小 ,但培养 36h加入各种佐剂后 PBMC增殖反应未见增强。 PBMC代表机体总的细胞免疫水平 ,通过佐剂对体外培养的PBMC增殖反应水平影响的测定 ,为动物用免疫佐剂和免疫增强剂的筛选提供了一种有效方法。     

Effects of weaning and syndyphalin-33 on expression of melanocortinergic appetite-regulating genes in swine

Syndyphalin-33 (SD-33) increases feed intake in sheep and recently weaned pigs. To assess the effects of SD-33 on hypothalamic gene expression, hypothalami were collected from unweaned pigs (n=19; 21±3 d of age) on day 0. Remaining pigs received an intramuscular injection of 0.5 μmole/kg SD-33 (SD) or saline (VEH) and weaned into individual pens. On days 1, 4, and 7 after weaning, hypothalami were collected from subsets of pigs (n=8 or 9) within each treatment group. Expression of μ-opioid receptor (MOR) was less in SD pigs than in VEH pigs on day 1 and day 4, suggesting down-regulation of the receptor by SD-33. Expression of hypothalamic melanocortin 4 receptor (MC4R) at 1 d after weaning was increased in VEH pigs (but not SD pigs) relative to levels before weaning. Expression of AGRP was not significantly altered by weaning or treatment at 1 d after weaning. At 4 d after weaning, expression of AGRP was greater in SD pigs than in VEH pigs, but at day 7 expression was less in SD pigs than in VEH pigs. A strong positive correlation was noted between expression levels of MOR and MC4R across treatment and time. Treatment with SD-33 appeared to partially abrogate the effects of weaning on expression of two key appetite-regulating genes within 24 h. Effects of SD-33 appear to be mediated at least in part by the μ-opioid receptor and include actions on the melanocortinergic pathway.     

Effects of the mycotoxin zearalenone on swine reproduction

Concentrations of 25, 50, or 100 ppm of 95% purified zearalenone fed to groups of healthy, multiparous sows during preestrus or throughout the gestation period (or both) produced multiple reproductive deficiencies. These reproductive disorders included infertility, constant estrus, pseudopregnancy, diminished fertility, reduced litter size, smaller offspring, malformation, juvenile hyperestrogenism, and probably fetal resorption. Gross and histologic examinations of sows revealed lesions in the reproductive organs. Marked epithelial changes characterized by squamous metaplasia were noticed in the uterus, uterine duct, cervix, vagina, and mammary glands.     

Interferon-gamma response of PBMC indicates productive pseudorabies virus (PRV) infection in swine

In Chinese Meishan/German Landrace cross-bred swine F2 generation interferon gamma (IFN-gamma) production by peripheral blood mononuclear cells (PBMC) was determined directly ex vivo at different time points after survival of a virulent pseudorabies virus (PRV) infection. This reactivity was compared with the reactivity of na?ve PBMC. Significant IFN-gamma production was determined in ELISA and ELISPOT only after in vitro PBMC re-stimulation with PRV and not with the closely related bovine herpesvirus BHV-1. The PRV-specific IFN-gamma secretion from re-stimulated PBMC showed high levels 6 days after infection, before the presence of serum antibodies, and it persisted at a high level over a 3 months period. The response of a group of eight piglets infected intranasally with PRV varied. Only two animals showed the expected typical fever response. PRV specific IFN-gamma production by PBMC clearly indicated that infection had occurred. Early significant IFN-gamma production by primed PBMC turned out to be a reliable and specific ex vivo marker for cellular response against productive PRV infection in swine before antibody formation.     

Effects of copper deficiency on T-cell mitogenic responsiveness and phenotypic profile of blood mononuclear cells from swine.

The effect of dietary copper deficiency on T-cell mitogenic responsiveness and phenotypic profile of blood mononuclear cells (MNC) in weaned pigs was examined. Outbred, weaned pigs were fed a semipurified diet containing adequate (6.4 mg/kg of body weight) or deficient (0.8 mg/kg) amounts of Cu. Pigs fed the low Cu diet for 10 weeks had markedly decreased concentrations of Cu in liver and plasma, and hypertrophic hearts. In vitro reactivity of MNC from Cu-deficient pigs to phytohemagglutinin and concanavalin A was significantly suppressed. This functional impairment was not associated with a decrease in the percentage of T cells, CD4 or CD8 cell subsets, or B cells. Expression of SLA-DQ and SLA-DR class II major histocompatibility complex (MHC) antigens was increased by Cu deficiency, the former significantly. Unlike rodents, in which inadequate Cu nutriture induces functional T cell deficiency that is associated with a decrease in the CD4 T-cell subset, swine fed inadequate Cu diets for 10 weeks had no changes in MNC subsets yet clearly manifested functional impairment of T-cell responses.     

猪流感病毒毒株感染对猪外周血淋巴细胞炎性因子转录时相的影响

试验用猪流感病毒（Swine influenza virus,SIV）（毒株）体外感染猪外周血淋巴细胞（Peripheral blood mononuclear cell,PBMC）,利用real—timePCR方法对病毒感染不同时间细胞中的病毒量和炎性细胞因子mRNA表达量进行检测。结果显示,感染后1h就可检测到病毒,但病毒量相对较小;在24h时病毒开始大量增殖;在72h病毒量达到最高峰,为1h时20倍以上。IL-1βmRNA的表达量在48h增加到最高;IL-6mRNA的表达量在感染后1h内显著增加;IL-8mRNA的表达量在12h时达到最大量;IL-12P35mRNA的表达量在72h迅速上升,为对照的56．1倍;IL-12P40mRNA的表达量在1～2h表达量较高;IL-13在72h达到最大值,为对照的30．7倍;IL-17mR—NA的表达量在72h达到最大值,为对照的4．9倍;IL-18mRNA的表达量在12h达到对照的1．9倍。结果表明,SIV感染PBMC后,随着病毒的大量复制,多种炎性细胞因子表达量显著增加。     

利用真核表达的猪流感病毒NP蛋白制备其特异性的单克隆抗体

为制备猪流感病毒(SIV)核蛋白(NP)单克隆抗体(MAb),本研究将重组质粒pMD-NP中含有的SIVNP基因亚克隆于pCAGGS真核表达质粒中,获得重组质粒pCAGGS-NP,将其转染293T细胞,通过间接免疫荧光(IFA)和western blot检测表明NP蛋白在293T细胞中获得了表达。将pCAGGS-NP以100μg/只剂量免疫4周龄～5周龄BALB/c小鼠,3次免疫后,利用杂交瘤细胞融合技术获得1株稳定分泌抗SIVNP的MAb杂交瘤细胞株(3D7);该MAb经Ig亚类鉴定为IgM,轻链为κ链,其诱导小鼠产生的腹水ELISA效价为1:105;纯化3D7腹水并对其进行亲和力及抗原结合活性的测定,ELISA曲线图显示亲和力常数为1.02×106M-1,IFA结果显示其可与H1N1、H3N2、H9N2亚型SIV发生特异性反应,具有良好的反应活性。该MAb的制备将为进一步建立猪流感的诊断方法以及分析NP蛋白抗原表位等方面的研究奠定基础。     

猪补体C5a蛋白表达、纯化和生物学活性检测

参照NCBI中公布的猪补体C5a蛋白氨基酸序列及猪C5蛋白的全基因序列,通过生物信息学分析获得猪C5a蛋白基因全长,为222 bp,该序列定向插入原核表达载体p ET-28a中,转化E.coli BL21(DE3),IPTG诱导表达,SDSPAGE和Western-blotting检测分析表明,C5a基因获得表达,重组蛋白大小为10 000。利用镍柱亲和层析进行蛋白纯化后,体外细胞试验测定重组C5a蛋白生物学活性。结果显示,成功构建了p ET-28a-C5a重组质粒,纯化获得目的蛋白纯度达到90%以上,质量浓度为2.5 g/L。细胞试验检测到C5a具有趋化和诱导中性粒细胞的活性。本研究为揭示猪C5a参与炎症过程的作用机制及制备C5a拮抗剂奠定了基础。     

CpG ODN免疫佐剂效应研究进展

人工合成的含非甲基化CpG基序的寡聚脱氧核苷酸(CpG ODN)能够与树突状细胞、B细胞、单核细胞及巨噬细胞等免疫细胞内质网膜上的Toll样受体9(TLR-9)结合,通过产生Th1型免疫反应和分泌促炎因子来增强免疫应答的强度,在机体抵抗病原入侵和抗肿瘤等方面起到免疫增强剂的作用。近年来,CpG ODN作为一种新型免疫佐剂受到了人们越来越多的关注。论文主要介绍了CpG ODN的种类及其结构和功能特征、作用机制、对畜禽的免疫增强作用、安全性等方面的研究进展,为CpG ODN作为疫苗佐剂的进一步研究和在兽医临床上的应用提供参考。     

猪瘟病毒Core蛋白的原核表达和抗体制备及应用

根据猪瘟病毒衣壳蛋白(Core)基因序列设计一对特异性引物,RT-PCR从猪瘟兔化弱毒中扩增出完整的Core基因,经酶切和序列测定后,克隆到携带His标签的原核表达载体p ColdⅠ中,成功构建了重组质粒p Cold-Core,并转化到大肠杆菌Rosseta 2(R2)中;利用IPTG诱导表达目的蛋白并鉴定表达效果。结果表明:经终浓度为0.1 mmol/L IPTG诱导24 h后,Core基因在R2中获得分泌性可溶表达,表达量占菌体蛋白的32.6%,SDS-PAGE显示目的蛋白相对分子质量为20 ku。Western blot结果显示Core蛋白可以分别与His单抗和猪瘟病毒阳性抗血清发生特异性反应,均出现单一反应带。将目的蛋白切胶后免疫Balb/c小鼠,制备特异性抗血清,Western blot结果显示该抗血清与衣壳蛋白反应后有明显的特异性条带,经激光共聚焦鉴定抗血清能够与胞浆中的猪瘟病毒粒子发生反应。结果表明,Core基因表达成功,制备的抗血清具有生物学功能。本研究为深入探讨Core蛋白在猪瘟病毒致病机制上的作用奠定了基础。     

猪NLRP3基因克隆及其在DF-1细胞的表达

NLRP3蛋白作为NLRP3炎性小体的主要组成蛋白之一,在机体对抗病原微生物和炎症反应中起着重要作用。为了深入研究猪的NLRP3蛋白在炎性疾病发生过程中的作用机制,采用PCR的方法扩增了长白猪NLRP3基因,并对其序列和编码蛋白的结构进行了分析。构建了pIRES2-EGFP-NLRP3真核表达载体,并转染至DF-1细胞中进行表达。结果显示,该基因表现出种属内保守性和种属间差异性,编码蛋白由1 036个氨基酸构成,存在4个潜在跨膜区,分别是第401~419,第721~739,第775~795和第889~910位氨基酸,不含信号肽。单层细胞免疫化学检测结果显示,重组质粒pIRES2-EGFP-NLRP3成功转染并在细胞中表达。本研究为深入探讨炎症小体在猪炎症性疾病的作用机制提供了基础数据。     

血浆蛋白粉的作用机制及其在猪生产中的应用

本文对血浆蛋白粉的生物安全性及营养特征、作用机制及其在猪生产中的应用效果和适宜添加量作一综述.