PCV2对仔猪胸腺IL-2、IL-6和IL-10及其受体mRNA的影响及NO-NOS系统的调控  

Effect of PCV2 on mRNA of IL-2,IL-6,IL-10 and their receptors in piglet thymus and the regulation of NO-NOS system

作　　者：陈耿[1] 张书霞[1] 华利忠[1] 

机构地区：[1]南京农业大学动物医学院,江苏南京210095

出　　处：《南京农业大学学报》2011年第3期101-106,共6页Journal of Nanjing Agricultural University

基　　金：国家自然科学基金项目(30471302;30871848)

摘　　要：为了解猪圆环病毒Ⅱ型(porcine circovirus Ⅱ,PCV2)引起仔猪免疫抑制的机制,研究了胸腺中抗感染免疫相关基因的动态表达变化及其调控机制。选取19头PCV2和猪繁殖与呼吸综合征病毒(PRRSV)血清抗体阴性的普通断奶仔猪,分为对照组(4头)和试验组(15头),试验组每头仔猪接种PCV2病毒悬液,分别在感染后0、14、21和35 d扑杀采集胸腺。用硝酸还原酶法检测一氧化氮(NO)的含量,用比色法检测总一氧化氮合酶(TNOS)和诱导型一氧化氮合酶(iNOS)的活性,用TQ-PCR方法检测胸腺中IL-2、IL-6、IL-10及其受体mRNA的表达变化。结果显示:感染猪胸腺中TNOS和iNOS的活性在试验期间均显著高于对照猪(P<0.05),NO含量在感染后14 d极显著升高(P<0.01),IL-2和IL-6 mRNA的表达在感染后各时间点均低于对照猪,尤其在感染后21 d均极显著降低(P<0.01);IL-10 mRNA的表达在感染后14 d极显著升高(P<0.01);IL-6和IL-10与各自受体mRNA的表达变化均呈显著负相关(P<0.05),NO与iNOS mRNA呈显著正相关(P<0.05)。研究表明:胸腺在感染早期表现出较强且适度的抗PCV2感染的免疫应答,感染中期呈现一定的免疫抑制,感染后期有所恢复;胸腺中细胞因子及其受体与NO-NOS系统的相互调节表现出复杂性与多层次性。To gain insight into the mechanism of immune suppression caused by porcine circovirus Ⅱ（PCV2）in piglets.The dynamic changes of relative anti-infection gene expression and its regulation was studied.Nineteen conventional post-weaning piglets which were free of PCV2 and porcine reproductive and respiratory syndrome virus（PRRSV）antibody were chosen,randomly distributed in the control group（n=4）and the experiment group（n=15）,and every piglet in experiment group was inoculated with PCV2,and the thymus were collected at 0,14,21 and 35 day post-inoculated（DPI）.The levels of nitric oxide（NO）and the activity of total nitric oxide synthase（TNOS）and inducible nitric oxide synthase（iNOS）were evaluated by nitrate reductase method and colorimetric genes mRNA method,and the expression changes of correlated genes mRNA were investigated by fluorescent quantitation PCR（FQ-PCR）.The results showed that the levels of NO in thymus of the piglets in experiment group significantly increased at 14 DPI.The change tendencies of TNOS were quite consistent with the changes of iNOS,and both of them notably increased（P0.01）first,and then went down,but always more than them in the control group（P0.05）.The expression levels of IL-2 and IL-6 mRNA in thymus of the piglets in experiment group were always lower than those in control group during the whole experiment,and especially at 21 DPI they extremely significantly decreased（P0.01）.The expression level of IL-10 mRNA extremely notably increased at 14 DPI（P0.01）.The mRNA expression changes of IL-6 and IL-10 were negatively correlated with the receptors of themselves post-inoculated,the level of NO and the activity of iNOS showed significantly positive correlation（P0.05）,there being an obvious positive correlation between NO and iNOS mRNA（P0.05）.The present study demonstrated that the immune response of anti-PCV2 in thymus appeared powerful and appropriate during the early stage of inoculation,there was an immunosuppression during the in

关 键 词：仔猪 猪圆环病毒Ⅱ型 细胞因子 一氧化氮 一氧化氮合酶 

分 类 号：S852.6[农业科学—基础兽医学]