Department of Disease Control, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
Department of Disease Control, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan; Department of Advanced Pharmaceutics, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
Poult Sci. 2023 Apr;102(4):102532. doi: 10.1016/j.psj.2023.102532. Epub 2023 Jan 26.
The poultry red mite (Dermanyssus gallinae, PRM) is a blood-sucking ectoparasite in chickens and is one of the most serious threats to poultry farms. Mass infestation with PRMs causes various health problems in chickens, resulting in significant productivity reduction in the poultry industry. Infestation with hematophagous ectoparasites, such as ticks, induces host inflammatory and hemostatic reactions. On the other hand, several studies have reported that hematophagous ectoparasites secrete various immunosuppressants from their saliva to suppress host immune responses to maintain blood sucking. Here, we examined the expression of cytokines in peripheral blood cells to investigate whether PRM infestation affects immunological states in chickens. In PRM-infested chickens, anti-inflammatory cytokines, IL-10 and TGF-β1, and immune checkpoint molecules, CTLA-4 and PD-1, were highly expressed compared to noninfested chickens. PRM-derived soluble mite extracts (SME) upregulated the gene expression of IL-10 in peripheral blood cells and HD-11 chicken macrophages. In addition, SME suppressed the expression of interferons and inflammatory cytokines in HD-11 chicken macrophages. Moreover, SME induces the polarization of macrophages into anti-inflammatory phenotypes. Collectively, PRM infestation could affect host immune responses, especially suppress the inflammatory responses. Further studies are warranted to fully understand the influence of PRM infestation on host immunity.
鸡血红螨（Dermanyssus gallinae，PRM）是鸡的一种吸血外寄生虫，是对家禽养殖场的最严重威胁之一。大量感染 PRM 会导致鸡出现各种健康问题，从而导致家禽业生产力大幅下降。吸血外寄生虫的感染，如蜱虫，会引起宿主的炎症和止血反应。另一方面，有几项研究报告称，吸血外寄生虫从唾液中分泌出各种免疫抑制剂，以抑制宿主对吸血的免疫反应。在这里，我们检查了外周血细胞中的细胞因子表达，以研究 PRM 感染是否会影响鸡的免疫状态。与未感染的鸡相比，感染 PRM 的鸡中抗炎细胞因子 IL-10 和 TGF-β1 以及免疫检查点分子 CTLA-4 和 PD-1 的表达水平较高。PRM 衍生的可溶性螨提取物（SME）上调了外周血细胞和 HD-11 鸡巨噬细胞中 IL-10 的基因表达。此外，SME 抑制了 HD-11 鸡巨噬细胞中干扰素和炎症细胞因子的表达。此外，SME 诱导巨噬细胞向抗炎表型极化。总之，PRM 感染可能会影响宿主的免疫反应，特别是抑制炎症反应。需要进一步的研究来充分了解 PRM 感染对宿主免疫的影响。
