宿主对病原微生物的应答可能导致白细胞介素（IL）-17的表达，其具有抗微生物和抗病毒活性。然而，关于鸡IL-17A对禽类病毒，特别是对马立克病病毒（MDV）的基本生物学作用，所知甚少。我们证明，在MDV感染后，与对照鸡相比，在脾脏中IL-17A mRNA的上调和IL-17A+ T细胞频率的增加发生。为了阐明chIL-17A在MD中的作用，将完整的chIL-17A编码序列克隆到pCDNA3.1-V5 / HIS TOPO质粒中。评估了pcDNA:chIL-17A质粒与疫苗（HVT）和高毒力（vv）MDV挑战或vvMDV感染联合治疗的效果。在与HVT疫苗联合接种时，接种pcDNA:chIL-17A质粒的鸡群的肿瘤发生率较接种空载体对照或仅接种的鸡要低（HVT + empty vector组为66.6％，HVT组为73.33％，而HVT + pcDNA:chIL-17A组为53.3％）。进一步分析表明，接种HVT疫苗和/或表达IL-17A的质粒的鸡的脾脏中MDV-Meq转录本较低。总之，chIL-17A可能影响HVT疫苗对鸡MDV感染的免疫力。

The host response to pathogenic microbes can lead to expression of interleukin (IL)-17, which has antimicrobial and anti-viral activity. However, relatively little is known about the basic biological role of chicken IL-17A against avian viruses, particularly against Marek's disease virus (MDV). We demonstrate that, following MDV infection, upregulation of IL-17A mRNA and an increase in the frequency of IL-17A+ T cells in the spleen occur compared to control chickens. To elaborate on the role of chIL-17A in MD, the full-length chIL-17A coding sequence was cloned into a pCDNA3.1-V5/HIS TOPO plasmid. The effect of treatment with pcDNA:chIL-17A plasmid in combination with a vaccine (HVT) and very virulent(vv)MDV challenge or vvMDV infection was assessed. In combination with HVT vaccination, chickens that were inoculated with the pcDNA:chIL-17A plasmid had reduced tumor incidence compared to chickens that received the empty vector control or that were vaccinated only (66.6% in the HVT + empty vector group and 73.33% in HVT group versus 53.3% in the HVT + pcDNA:chIL-17A). Further analysis demonstrated that the chickens that received the HVT vaccine and/or plasmid expressing IL-17A had lower MDV-Meq transcripts in the spleen. In conclusion, chIL-17A can influence the immunity conferred by HVT vaccination against MDV infection in chickens.