United States Department of Agriculture, Agricultural Research Service, Avian Disease and Oncology Laboratory, East Lansing, Michigan 48823, USA.
Viral Immunol. 2012 Aug;25(4):306-23. doi: 10.1089/vim.2012.0003. Epub 2012 Jul 17.
Marek's disease (MD) is a lymphoproliferative disease of domestic chickens caused by a highly cell-associated alpha herpesvirus, Marek's disease virus (MDV). Clinical signs of MD include depression, crippling, weight loss, and transient paralysis (TP). TP is a disease of the central nervous system that affects MD-susceptible chickens 8-11 days post-infection (dpi), normally resulting in recovery 1-3 d after the onset of clinical signs. In this study we inoculated chickens from lines 7(2) (MD-susceptible) and 6(3) (MD-resistant) with a very virulent plus strain of MDV at 2 wk of age, and collected brain samples from birds with and without TP at 5, 11, and 21 dpi for gene expression profiling and histological analysis. Data revealed that chickens inoculated with MDV had higher levels of IL-6, IL-10, IL-18, IFN-α, IFN-β, IFN-γ, MHC I, and CD18 in their brains at 11 dpi compared to the uninfected control birds. In addition, the expression levels of IL-6, IL-10, IFN-α, IFN-β, and IFN-γ were significantly higher in the brains of the birds showing clinical signs of TP than in asymptomatic chickens. Comparative analysis between the two chicken lines showed that the expression levels of IL-6, IL-10, IFN-β, IFN-γ, IL-18, CD18, and MHC I were significantly higher in the brains of the birds from line 6(3) with TP than those of line 7(2) exhibiting neurological disorders. A differential expression pattern was observed for some of the tested genes at different time points post-inoculation. Histological analysis showed lymphocytic meningitis, perivascular cuffing, and neuronal degeneration within the brains of birds from both susceptible and resistant lines exhibiting TP at 11 dpi. Vaccination prevented development of TP and other MD-associated clinical symptoms. These observations are suggestive of an underlying immunological mechanism for viral-induced neurological dysfunction, and the differential responses of the two chicken lines to MDV infection.
马立克氏病（MD）是一种由高度细胞相关的α疱疹病毒，即马立克氏病病毒（MDV）引起的家禽淋巴组织增生性疾病。MD 的临床症状包括抑郁、跛行、体重减轻和短暂性瘫痪（TP）。TP 是一种中枢神经系统疾病，影响 8-11 日龄感染（dpi）的 MD 易感鸡，通常在临床症状出现后 1-3 天恢复。在这项研究中，我们用一种非常强毒 plus 株 MDV 感染 2 周龄的 7(2)（MD 易感）和 6(3)（MD 抗性）系鸡，并在 5、11 和 21 dpi 时从有和无 TP 的鸟类中收集脑组织样本进行基因表达谱分析和组织学分析。数据显示，感染 MDV 的鸡在 11 dpi 时大脑中的 IL-6、IL-10、IL-18、IFN-α、IFN-β、IFN-γ、MHC I 和 CD18 水平高于未感染对照鸡。此外，表现出 TP 临床症状的鸟类大脑中 IL-6、IL-10、IFN-α、IFN-β 和 IFN-γ 的表达水平明显高于无症状鸡。在两条鸡线之间的比较分析中，表现出 TP 的 6(3)系鸡的大脑中 IL-6、IL-10、IFN-β、IFN-γ、IL-18、CD18 和 MHC I 的表达水平明显高于表现出神经障碍的 7(2)系鸡。在接种后不同时间点，一些测试基因的表达模式存在差异。组织学分析显示，在 11 dpi 时，具有 TP 的易感和抗性系鸟类的大脑中出现淋巴细胞性脑膜炎、血管周围套袖和神经元变性。疫苗接种可预防 TP 和其他 MD 相关临床症状的发生。这些观察结果表明了病毒诱导的神经功能障碍的潜在免疫机制，以及两条鸡线对 MDV 感染的不同反应。
