由于放线杆菌性胸膜肺炎（APP）感染导致猪产业损失巨大，因此需要开发有效的治疗手段，利用宿主免疫防御机制来对抗这些病原体。本研究旨在证明微RNA（miR）-127在控制对抗APP细菌感染方面的作用。此外，还研究了在巨噬细胞中控制抗微生物肽产生的信号途径。首先，我们通过细胞计数/酶联免疫吸附法（ELISA）评估了miR-127对APP感染猪的影响。然后检测了miR-127对免疫细胞的影响。细胞因子肿瘤坏死因子（TNF）-α和白细胞介素（IL）-6通过ELISA测定。使用定量聚合酶链反应评估了细胞因子（抗微生物肽[AMP]）的表达。通过Western blot分析IL-6，TNF-α和p-P65的表达水平。使用免疫荧光法研究免疫细胞中p65的表达。miR-127对APP感染的巨噬细胞具有保护作用。此外，保护作用可能依赖于其调节巨噬细胞杀菌活性以及靶向神经酰胺-1磷酸受体3（SIPR3）调节IL-22，IL-17和AMP的生成。 SIPR3是涉及Toll样受体（TLR）级联的元素。我们发现miR-127是S1PR3的调节器，然后调节巨噬细胞中的TLR /核因子-kB信号，具有抗细菌活性，可能是治疗由APP引起的炎症性疾病的潜在靶点。© 2023年韩国兽医科学学会。

As Actinobacillus pleuropneumonniae (APP) infection causes considerable losses in the pig industry, there is a growing need to develop effective therapeutic interventions that leverage host immune defense mechanisms to combat these pathogens.To demonstrate the role of microRNA (miR)-127 in controlling bacterial infection against APP. Moreover, to investigate a signaling pathway in macrophages that controls the production of anti-microbial peptides.Firstly, we evaluated the effect of miR-127 on APP-infected pigs by cell count/enzyme-linked immunosorbent assay (ELISA). Then the impact of miR-127 on immune cells was detected. The cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-6 were evaluated by ELISA. The expression of cytokines (anti-microbial peptides [AMPs]) was assessed using quantitative polymerase chain reaction. The expression level of IL-6, TNF-α and p-P65 were analyzed by western blot. The expression of p65 in the immune cells was investigated by immunofluorescence.miR-127 showed a protective effect on APP-infected macrophage. Moreover, the protective effect might depend on its regulation of macrophage bactericidal activity and the generation of IL-22, IL-17 and AMPs by targeting sphingosine-1-phosphate receptor3 (SIPR3), the element involved in the Toll-like receptor (TLR) cascades.Together, we identify that miR-127 is a regulator of S1PR3 and then regulates TLR/nuclear factor-κB signaling in macrophages with anti-bacterial acticity, and it might be a potential target for treating inflammatory diseases caused by APP.© 2023 The Korean Society of Veterinary Science.