E.tenella感染早期雏鸡盲肠扁桃体ChIL-17A和ChIL-17F表达水平的相反变化

Opposite regulation of ChIL-17A and ChIL-17F expression in chicken cecal tonsil in early period of E.tenellainfection

为探讨ChIL-17及其受体在抗柔嫩艾美耳球虫（E．tenella）感染中的作用，本研究用E．tenellaRC株孢子化卵囊口服感染14日龄非免疫蛋公鸡，于感染后0，2，4，6，12，24，3，5，7d共9个不同时间点同时提取对照组和试验组雏鸡盲肠扁桃体RNA，采用实时荧光定量PCR方法检测ChIL-17A、ChIL-17F和ChIL-17RA基因的表达动态。结果显示，ChIL-17A表达水平在感染后持续下调，感染后4h为感染前（0h）的0．13倍（P〈0．01），感染后3d达最低表达水平，仅为感染前（0h）的0．0097倍。而ChIL-17F的表达水平则呈现相反的变化，在感染早期明显上调，感染后2h上调3．07倍（P〈O．05），感染后4h上调6．49倍（P〈0．01），其后时间点与感染前相比表达水平则无显著性差异。ChIL-17RA与感染前相比表达上调，于感染后24h和7d分别上调1．73倍和2．21倍（P〈0．01）。结果表明，ChIL-17及其受体基因的表达水平在感染后均呈现显著变化，说明它们在E．tenella感染中具有重要的宿主-寄生虫免疫生物学意义。特别是ChIL-17A和ChIL-17F在感染早期（感染后2～4h）表现出显著的相反表达动态说明两者在宿主防御E-tenella感染的早期具有不同的免疫调节功能，而这一具体调节机制还有待于进一步的研究加以阐明。

In order to research the roles of ChlL-17 and its receptor ChIL-17RA,the expression level of ChIL-17A,ChIL-17F and ChIL-17RA at 0,2,4,6,12,24 h and 3,5,7 d in cecal tonsil of chick- en orally infected with E. tenella RC strain was determined by means of real-time RT-PCR respectively. The results showed that ChlL-17A expression was constantly down-regulated, its relative expression level at 4 h post-infection was 0.13 times of that at 0 h （P〈0. 01） ,and reached the lowest expression level at 3 d post-infection that was only 0. 009 7 times of that at 0 h. On the con- trary,ChIL-17F expression was up-regulated after infection,especially in the early phase after in- fection,its relative expression level was up-regulated by 3.07 folds （P〈0.05） and 6.49 folds （P 〈0.01） at 2 h and 4 h post-infection,respectively. The expression level of ChIL-17RA was moder- ately up-regulated by 1.73 folds and 2.21 folds （P〈0.01） at 24 h and 7 d post-infection,respectively. The significant changes of the expression level of ChIL-17 and its receptor genes after E. tenella infection indicate that they have on important significance of host-parasite immunobiology. Especially, the opposite regulation of ChIL-17A and ChIL-17F expression suggest that they play different roles in immune regulation in the early stage post-infection,but its detailed mecha- nism remains to be uncovered by further researches.