藏鸡和隐性白羽鸡感染柔嫩艾美耳球虫后免疫相关基因的表达变化分析

Expression Changes of Immune-related Genes in Tibetan Chickens and Recessive White Chickens Following Eimeria tenella Infection

试验旨在从免疫遗传学的角度初步探讨藏鸡(TC)和隐性白羽鸡(RWC)对柔嫩艾美耳球虫(Eimeria tenella)易感性差异的分子机制,分别用1×105个柔嫩艾美耳球虫孢子化卵囊感染对球虫具有抗性的藏鸡和易感的隐性白羽鸡。应用实时荧光定量PCR检测藏鸡和隐性白羽鸡感染前0 d和感染后第2、4、6和8天脾脏、盲肠、胸腺、法氏囊中γ-干扰素(IFN-γ)、白细胞介素-2(IL-2)、IL-16、Toll样受体(TLR3)和TLR15免疫相关基因的转录水平变化。结果显示,藏鸡脾脏IFN-γ、IL-2、IL-16及TLR3、TLR15免疫相关基因转录水平于感染后第4和8天明显上调,隐性白羽鸡则无明显变化。藏鸡盲肠IFN-γ转录水平在感染后第2天显著上调(P<0.05),TLR3在感染后第4天起显著上调(P<0.05),其余免疫相关基因变化幅度不大;隐性白羽鸡盲肠IFN-γ转录水平在感染后第8天显著上调(P<0.05),IL-2在感染后第2天起显著上调(P<0.05),IL-16在感染后第6天起显著上调(P<0.05),TLR3在感染后第2和8天显著上调(P<0.05),TLR15变化幅度不大。各免疫相关基因在2个品种鸡胸腺和法氏囊中均出现上调或下调,但除藏鸡法氏囊TLR3和TLR15转录水平变化幅度相对较大外,其余免疫相关基因与感染前相比变化幅度不大。以上结果显示,球虫感染主要导致藏鸡和隐性白羽鸡脾脏和盲肠中的各免疫相关基因出现显著变化,表明宿主的遗传背景在一定程度上可影响球虫感染的免疫应答。

In order to preliminarily explore the molecular mechanism of the difference in the susceptibility of Tibetan chickens and Recessive White chickens to Eimeria tenella(E.tenella)from the perspective of immunogenetics,1×105 live E.tenella sporulated oocysts were used to infect Tibetan chickens and Recessive White chickens,respectively,which displayed different levels of susceptibility to E.tenella infection.The transcription level of IFN-γ,IL-2,IL-16,TLR3 and TLR15 in spleen,cecum,thymus and bursa of Fabricius were detected by Real-time PCR at 0 d before infection and at the 2nd,4th,6th and 8th day after infection.The results showed that the transcription levels of IFN-γ,IL-2,IL-16,TLR3 and TLR15 in the spleen of Tibetan chickens were up-regulated on the 4th and 8th day after infection,while that of Recessive White chickens were not obviously changed.The transcription level of IFN-γin the cecum of Tibetan chickens were significantly up-regulated on the 2nd day after infection(P<0.05),TLR3 was significantly up-regulated from the 4th day after infection(P<0.05),and other immune-related genes showed little change.The transcription level of IFN-γin the cecum of Recessive White chickens were significantly up-regulated on the 8th day after infection(P<0.05),IL-2 was significantly up-regulated from the 2nd day after infection(P<0.05),IL-16 was significantly up-regulated from the 6th day after infection(P<0.05),TLR3 was significantly up-regulated on the 2nd and 8th day after infection(P<0.05),and TLR15 had little change.All immune related genes were up-regulated or down-regulated in thymus and bursa of Fabricius of the two breeds,but the transcription level of TLR3 and TLR15 in bursa of Fabricius of Tibetan chickens showed relatively large changes,while the other immune-related genes showed little changes compared with that before infection.The above results showed that E.tenella infection mainly resulted in significant changes in immune related genes in spleen and cecum of Tibetan chickens and Recessive White chickens,indicating that the genetic background of host would affect the immune response of coccidiosis infection to a certain extent.