巨型艾美耳球虫感染对鸡Toll样受体的影响

Effect of Eimeria maxima infection on Toll-like receptors in chickens

为了探究巨型艾美耳球虫(Eimeria maxima)感染对宿主局部免疫组织盲肠扁桃体和系统免疫组织(脾脏和外周血)中Toll样受体(Toll like receptor,TLR)的影响,用巨型艾美耳球虫感染雏鸡,感染后第0、3、7和11天,采集鸡盲肠扁桃体、外周血和脾脏淋巴细胞,用实时荧光定量PCR检测上述组织中8种鸡TLR的mRNA水平变化。结果显示:TLR4和TLR21 mRNA水平在3种组织中无显著变化;TLR2 mRNA水平在感染后第3天开始在外周血和脾脏中显著下降(P<0.05),在盲肠扁桃体中第3和7天无显著变化,在第11天显著上升(P<0.01)。TLR1、TLR3、TLR5、TLR7和TLR15 mRNA水平在3种组织中显著上升(P<0.05),但应答时间有所差异,具体为TLR1和TLR3 mRNA水平在盲肠扁桃体中在第3天开始上升,而在外周血和脾脏中第7天开始上升;TLR5和TLR15 mRNA水平在外周血和脾脏中第3天开始上升,而在盲肠扁桃体中第7天开始上升。结果表明:巨型艾美耳球虫感染上调宿主3种组织中的TLR1、TLR3、TLR5、TLR7和TLR15 mRNA水平,下调外周血和脾脏中的TLR2 mRNA水平;盲肠扁桃体TLR1和TLR3 mRNA水平上升早于外周血和脾脏,而其TLR5和TLR15 mRNA水平上升晚于外周血和脾脏。本研究为揭示鸡TLR在抗球虫感染中的作用提供依据,也为揭示鸡球虫先天性免疫机制提供参考。

This study was to explore the effect of Eimeria maxima infection on TLR in local immune tissues(cecal tonsils)and systemic immune tissues(spleen and peripheral blood)of the infected chickens.Chickens were infected with Eimeria maxima.On the 0,3rd,7th and 11th days after infection,the samples of cecal tonsils,peripheral blood and spleen lymphocytes were collected from the infected chickens,respectively.Then,the mRNA levels of 8 TLR in the tissues of the infected chicken were detected by real-time fluorescent quantitative PCR.The results showed that the mRNA levels of TLR4 and TLR21 did not exhibit significant changes in the three tissues.The mRNA level of TLR2 significantly decreased in the peripheral blood and spleen from the 3rd day after infection(P<0.05),but did not show significant changes in the cecal tonsils on the 3rd and 7th days,and increased significantly on the 11th day(P<0.01).The mRNA levels of TLR1,TLR3,TLR5,TLR7 and TLR15 increased significantly in the three tissues(P<0.05),but the response time was different.The mRNA levels of TLR1 and TLR3 began to rise on the 3rd day in the cecal tonsils,and on the 7th day in the peripheral blood and spleen.The mRNA levels of TLR5 and TLR15 began to rise on the 3rd day in peripheral blood and spleen,and on the 7th day in cecal tonsil.The levels of TLR1,TLR3,TLR5,TLR7 and TLR15 were up-regulated in the three tissues of the host after infection with Eimeria maxima,and TLR2 were down-regulated in their peripheral blood and spleen.These results indicated that the mRNA levels of TLR1 and TLR3 in the cecal tonsils increased earlier than those in the peripheral blood and spleen,while TLR5 and TLR15 increased later than those in the peripheral blood and spleen.This study laid a foundation for revealing the role of chicken TLR against coccidia infection,and provided a reference for revealing the innate immune mechanism of chicken coccidia.