Animal Health Laboratory, Department of Veterinary Medicine, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido, 069-8501, Japan.
Veterinary Biochemistry, Department of Veterinary Medicine, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido, 069-8501, Japan.
Vet Res. 2021 Apr 16;52(1):58. doi: 10.1186/s13567-021-00920-2.
Mycoplasma bovis (M. bovis) is a significant worldwide pathogen of cattle. Neutrophils have an important role in the innate immune response during infection with M. bovis. However, even though neutrophils accumulate in M. bovis infection, the interaction of M. bovis and neutrophils has not been fully elucidated. We attempted to elucidate the innate immune response of neutrophils stimulated with M. bovis and evaluate the transcriptome and functional analysis of bovine neutrophils stimulated with M. bovis. Proinflammatory cytokines, such as inducible nitric oxide (iNOS), which was the most increased gene in transcriptome analysis, were increased in quantitative polymerase chain reaction analysis of bovine neutrophils stimulated with live or heat-killed M. bovis. Nitric oxide and intracellular reactive oxygen species production of neutrophils stimulated with M. bovis was significantly increased. Neutrophils stimulated with M. bovis showed an increased ratio of nonapoptotic cell death compared to unstimulated controls. We demonstrated that neutrophil extracellular traps (NETs) formation was not recognized in neutrophils stimulated with live M. bovis. However, heat-killed M. bovis induced NETs formation. We also showed the interaction with M. bovis and bovine neutrophils regarding proinflammatory cytokine gene expression and functional expression related to NETs formation. Live and killed M. bovis induced innate immune responses in neutrophils and had the potential to induce NETs formation, but live M. bovis escaped NETs.
牛支原体(M. bovis)是一种全球性的牛重要病原体。中性粒细胞在感染牛支原体时的固有免疫反应中起重要作用。然而,尽管中性粒细胞在牛支原体感染中聚集,但牛支原体与中性粒细胞的相互作用尚未完全阐明。我们试图阐明牛支原体刺激中性粒细胞的固有免疫反应,并评估牛支原体刺激中性粒细胞的转录组和功能分析。在定量聚合酶链反应分析中,活的或热灭活的牛支原体刺激的牛中性粒细胞中诱导型一氧化氮合酶(iNOS)等促炎细胞因子的增加最为明显。牛支原体刺激的中性粒细胞中一氧化氮和细胞内活性氧的产生显著增加。与未刺激对照相比,牛支原体刺激的中性粒细胞的非凋亡性细胞死亡比例增加。我们证明,活的牛支原体刺激的中性粒细胞中未识别到中性粒细胞胞外诱捕网(NETs)的形成。然而,热灭活的牛支原体诱导了 NETs 的形成。我们还展示了牛支原体与牛中性粒细胞之间在促炎细胞因子基因表达和与 NETs 形成相关的功能表达方面的相互作用。活的和死的牛支原体诱导了中性粒细胞的固有免疫反应,并有可能诱导 NETs 的形成,但活的牛支原体逃避了 NETs。