Dalgaard Tina S, Skovgaard Kerstin, Norup Liselotte R, Pleidrup Janne, Permin Anders, Schou Torben W, Vadekær Dorte F, Jungersen Gregers, Juul-Madsen Helle R
Department of Animal Science, Aarhus University, Blichers Alle 20, DK-8830 Tjele, Denmark.
National Veterinary Institute, Division of Veterinary Diagnostics and Research, Technical University of Denmark, Bülowsvej 27, DK-1870 Frederiksberg C, Denmark.
Vet Immunol Immunopathol. 2015 Mar 15;164(1-2):79-86. doi: 10.1016/j.vetimm.2015.01.003. Epub 2015 Jan 14.
Ascaridia galli is a gastrointestinal nematode infecting chickens. Chickens kept in alternative rearing systems or at free-range experience increased risk for infection with resulting high prevalences. A. galli infection causes reduced weight gain, decreased egg production and in severe cases increased mortality. More importantly, the parasitised chickens are more susceptible to secondary infections and their ability to develop vaccine-induced protective immunity against other diseases may be compromised. Detailed information about the immune response to the natural infection may be exploited to enable future vaccine development. In the present study, expression of immune genes in the chicken spleen during an experimental infection with A. galli was investigated using the Fluidigm(®) BioMark™ microfluidic qPCR platform which combines automatic high-throughput with attractive low sample and reagent consumption. Spleenic transcription of immunological genes was compared between infected chickens and non-infected controls at week 2, 6, and 9 p.i. corresponding to different stages of parasite development/maturation. At week 2 p.i. increased expression of IL-13 was observed in infected chickens. Increased expression of MBL, CRP, IFN-α, IL-1β, IL-8, IL-12β and IL-18 followed at week 6 p.i. and at both week 6 and 9 p.i. expression of DEFβ1 was highly increased in infected chickens. In summary, apart from also earlier reported increased expression of the Th2 signature cytokine IL-13 we observed only few differentially expressed genes at week 2 p.i. which corresponds to the larvae histotrophic phase. In contrast, we observed increased expression of pro-inflammatory cytokines and acute phase proteins in infected chickens, by week 6 p.i. where the larvae re-enter the intestinal lumen. Increased expression of DEFβ1 was observed in infected chickens at week 6 p.i. but also at week 9 p.i. which corresponds to a matured stage where adult worms are present in the intestinal lumen.
鸡蛔虫是一种感染鸡的胃肠道线虫。饲养在替代饲养系统或自由放养环境中的鸡感染风险增加，感染率很高。鸡蛔虫感染会导致体重增加减缓、产蛋量下降，严重时死亡率会上升。更重要的是，受寄生虫感染的鸡更容易受到继发感染，其产生疫苗诱导的针对其他疾病的保护性免疫的能力可能会受到损害。关于对自然感染的免疫反应的详细信息可用于未来疫苗的研发。在本研究中，使用Fluidigm（®）BioMark™微流控qPCR平台研究了鸡在实验感染鸡蛔虫期间脾脏中免疫基因的表达，该平台结合了自动高通量以及低样本和试剂消耗量的优点。在感染后第2周、第6周和第9周，比较了感染鸡和未感染对照之间免疫基因的脾脏转录情况，这几个时间点分别对应寄生虫发育/成熟的不同阶段。在感染后第2周，观察到感染鸡中白细胞介素-13（IL-13）的表达增加。在感染后第6周，甘露糖结合凝集素（MBL）、C反应蛋白（CRP）、干扰素-α（IFN-α）、白细胞介素-1β（IL-1β）、白细胞介素-8（IL-8）、白细胞介素-12β和白细胞介素-18的表达增加，并且在感染后第6周和第9周，感染鸡中防御素β1（DEFβ1）的表达均显著增加。总之，除了之前报道的辅助性T细胞2（Th2）标志性细胞因子IL-13的表达增加外，我们在感染后第2周（对应幼虫组织营养期）仅观察到少数差异表达基因。相比之下，在感染后第6周（此时幼虫重新进入肠腔），我们观察到感染鸡中促炎细胞因子和急性期蛋白的表达增加。在感染后第6周以及第9周（对应成虫存在于肠腔的成熟阶段），感染鸡中均观察到DEFβ1的表达增加。
