Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China.
Front Cell Infect Microbiol. 2022 Jun 14;12:827750. doi: 10.3389/fcimb.2022.827750. eCollection 2022.
can cause liver abscess, foot rot in ruminants, and Lemire syndrome in humans, Also, its virulence factors can induce the apoptosis of macrophages and neutrophils. However, the detailed mechanism has not been fully clarified. This study investigated the mechanisms of apoptosis and inflammatory factor production in -induced neutrophils and macrophages (RAW246.7). After infection of macrophages with , 5-ethynyl-2'-deoxyuridine labeling assays indicated that inhibited macrophage proliferation in a time- and dose-dependent manner. Hoechst staining and DNA ladder assays showed significant condensation of the nucleus and fragmentation of genomic DNA in -infected macrophages, Annexin V (FITC) and propidium iodide (PI) assay confirmed the emergence of apoptosis in the macrophages and sheep neutrophils with compared with the control. The group with significant apoptosis was subjected to RNA sequencing (RNA-Seq), and the sequencing results revealed 2581 up- and 2907 downregulated genes. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis of the differentially expressed genes showed that drove apoptosis and production of inflammatory factors by activating genes related to the Nuclear Factor-κB (NF-κB) and death receptor pathways. Meanwhile, quantitative reverse transcription PCR and Western blot validation results were consistent with the results of transcriptome sequencing analysis. In conclusion, induced apoptosis and production of pro-inflammatory factors through the NF-κB and death receptor signaling pathway, providing a theoretical basis for further mechanistic studies on the prevention and control of disease treatment.
可导致肝脓肿、反刍动物腐蹄病和人类 Lemire 综合征，其毒力因子还可诱导巨噬细胞和中性粒细胞凋亡。然而，其详细的作用机制尚未完全阐明。本研究探讨了在诱导的中性粒细胞和巨噬细胞（RAW246.7）中凋亡和炎症因子产生的机制。用感染巨噬细胞后，5-乙炔基-2'-脱氧尿苷标记实验表明，呈时间和剂量依赖性抑制巨噬细胞增殖。Hoechst 染色和 DNA 梯带实验显示，感染的巨噬细胞核明显浓缩，基因组 DNA 片段化，与对照组相比， Annexin V（FITC）和碘化丙啶（PI）检测证实巨噬细胞和绵羊中性粒细胞中出现凋亡。对具有明显凋亡的细胞进行 RNA 测序（RNA-Seq），测序结果显示 2581 个上调和 2907 个下调基因。差异表达基因的基因本体论和京都基因与基因组百科全书分析表明，通过激活与核因子-κB（NF-κB）和死亡受体途径相关的基因，驱动凋亡和炎症因子的产生。同时，定量逆转录 PCR 和 Western blot 验证结果与转录组测序分析结果一致。综上所述，通过 NF-κB 和死亡受体信号通路诱导凋亡和产生促炎因子，为进一步研究预防和控制疾病的治疗机制提供了理论依据。
