He Jiaxin, Guo Yusi, Wang Yujiong, Zhao Gang
Key Laboratory of the Ministry of Education for Conservation and Utilization of Special Biological Resources in the Western, Yinchuan 750021, China; College of Life Science, Ningxia University, Yinchuan 750021, China.
Key Laboratory of the Ministry of Education for Conservation and Utilization of Special Biological Resources in the Western, Yinchuan 750021, China.
Int Immunopharmacol. 2025 Oct 10;163:115252. doi: 10.1016/j.intimp.2025.115252. Epub 2025 Jul 20.
Mycoplasma bovis (M. bovis), mainly causes pneumonia, mastitis, and arthritis in cattle, thereby leading to significant economic losses. The pathological damage caused by inflammation is key to the pathogenesis of M. bovis. The aim of this study was to reveal the role of extracellular vesicles (EVs) in M. bovis-host interaction and identified the key miRNAs in EVs. We used ultracentrifugation method to extract the EVs from the embryonic bovine lung (EBL) cells infected with M. bovis, then identified the miRNA profile of EVs by RNA sequencing. We identified 12 upregulated and 6 downregulated miRNAs in EVs + (derived from infected EBL cells) as compared to EVs- (uninfected controls). Furthermore, EVs + possessed the greater capacity to induce production of IL-1β, IL-6, IL-8, and TNF-α by bovine macrophage BoMac cells than EVs-, and enhanced the sensitivity of BoMac cells to produce pro-inflammatory cytokines upon infection of M. bovis. Additionally, bta-miR-199a-3p in EVs + promoted production of IL-6, IL-8, and TNF-α by BoMac cells via increasing expression of the target gene dual specificity phosphatase 5 (DUSP5). Collectively, these results suggested that EVs derived from epithelia cells EBL enhance the sensitivity of macrophage BoMac to response M. bovis infection. Moreover, bta-miR-199a-3p enriched in EVs + regulated the immune response of BoMac via up-regulation of DUSP5. These findings highlighted the roles of EVs in host cell resistance to M. bovis infection and provided new insights to explore the pathogenic mechanism of M. bovis.
牛支原体主要引起牛的肺炎、乳腺炎和关节炎，从而导致重大经济损失。炎症引起的病理损伤是牛支原体发病机制的关键。本研究旨在揭示细胞外囊泡（EVs）在牛支原体与宿主相互作用中的作用，并鉴定EVs中的关键微小RNA（miRNAs）。我们采用超速离心法从感染牛支原体的胚胎牛肺（EBL）细胞中提取EVs，然后通过RNA测序鉴定EVs的miRNA谱。与EVs-（未感染对照）相比，我们在EVs +（来自感染的EBL细胞）中鉴定出12个上调和6个下调的miRNAs。此外，EVs +比EVs-具有更强的诱导牛巨噬细胞BoMac细胞产生白细胞介素-1β（IL-1β）、白细胞介素-6（IL-6）、白细胞介素-8（IL-8）和肿瘤坏死因子-α（TNF-α）的能力，并增强了BoMac细胞在感染牛支原体时产生促炎细胞因子的敏感性。此外，EVs +中的bta-miR-199a-3p通过增加靶基因双特异性磷酸酶5（DUSP5）的表达促进BoMac细胞产生IL-6、IL-8和TNF-α。总体而言，这些结果表明，来源于上皮细胞EBL的EVs增强了巨噬细胞BoMac对牛支原体感染的反应敏感性。此外，EVs +中富集的bta-miR-199a-3p通过上调DUSP5调节BoMac的免疫反应。这些发现突出了EVs在宿主细胞抵抗牛支原体感染中的作用，并为探索牛支原体的致病机制提供了新的见解。
