Abstract Introduction Despite vaccination against avian metapneumoviruses (aMPV), cases of turkey rhinotracheitis (TRT) caused by aMPV field strains are frequently reported. Differences have been shown in the level of immune system stimulation after aMPV vaccination between turkeys that do and do not possess specific anti-aMPV maternally derived antibodies (MDA). The article describes the influence of MDA on the production of IFNγ in the spleen of aMPV-vaccinated turkeys. Material and Methods MDA+ or MDA− turkeys were vaccinated against TRT after hatching or on the 14th day of life. Spleen samples were collected 3, 7, and 14 days post vaccination for mononuclear cell isolation. Real-time PCR, flow cytometry, and the enzyme-linked immunospot assay were used to evaluate the levels of IFNγ gene expression, production, and secretion by cells within the spleen samples. Results Increased IFNγ gene expression was noticed after vaccination only in birds that did not possess MDA or possessed MDA at relatively low level (MDA+ birds vaccinated at 14 DOL). In all birds, an increased percentage of T lymphocytes producing IFNγ was recorded. The proportion of anti-aMPV IFNγ-secreting cells was increased only in MDA− birds. Conclusion Besides having a protective role, MDA are known to interfere with vaccination efficacy. The analysis of our results confirms that MDA can decrease the level of immune system stimulation after aMPV vaccination of turkeys.

中文翻译：

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TRT疫苗接种后不同免疫状态火鸡的IFNγ产生情况

摘要 简介 尽管针对禽偏肺病毒 (aMPV) 进行了疫苗接种，但由 aMPV 野毒株引起的火鸡鼻气管炎 (TRT) 病例仍经常报道。已显示在接种 aMPV 疫苗后免疫系统刺激水平在具有和不具有特异性抗 aMPV 母源抗体 (MDA) 的火鸡之间存在差异。该文章描述了 MDA 对 aMPV 疫苗接种火鸡脾脏中 IFNγ 产生的影响。材料和方法 MDA+ 或 MDA- 火鸡在孵化后或第 14 天接种 TRT。在接种疫苗后 3、7 和 14 天收集脾脏样品用于单核细胞分离。实时荧光定量 PCR、流式细胞术和酶联免疫斑点法用于评估 IFNγ 基因表达、产生、和脾脏样本内的细胞分泌。结果仅在不具有MDA或具有相对低水平的MDA的鸡只（MDA+鸡在14 DOL接种疫苗）后观察到增加的IFNγ基因表达。在所有鸡只中，记录到产生 IFNγ 的 T 淋巴细胞百分比增加。仅在 MDA-鸟中，抗 aMPV IFNγ 分泌细胞的比例增加。结论 除了具有保护作用外，已知 MDA 还会干扰疫苗接种效果。对我们结果的分析证实，MDA 可以降低火鸡接种 aMPV 后免疫系统的刺激水平。记录到产生 IFNγ 的 T 淋巴细胞百分比增加。仅在 MDA-鸟中，抗 aMPV IFNγ 分泌细胞的比例增加。结论 除了具有保护作用外，已知 MDA 还会干扰疫苗接种效果。对我们结果的分析证实，MDA 可以降低火鸡接种 aMPV 后免疫系统的刺激水平。记录到产生 IFNγ 的 T 淋巴细胞百分比增加。仅在 MDA-鸟中，抗 aMPV IFNγ 分泌细胞的比例增加。结论 除了具有保护作用外，已知 MDA 还会干扰疫苗接种效果。对我们结果的分析证实，MDA 可以降低火鸡接种 aMPV 后免疫系统的刺激水平。