在S期间阻断HXA3介导的中性粒细胞弹性酶释放. 肺炎的肺部感染限制了肺上皮质屏障的破坏和细菌病
Shuying Xu1,2, Shumin Tan1, Patricia Romanos1,3
1Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA.
mBio
|August 9, 2024
概括
素A3 (HXA3) 驱动链球菌肺炎 (Sp) 通过促进免疫细胞损伤和中性粒细胞弹性酶释放而传播. 向HXA3或中性粒细胞弹性酶可能为Sp肺炎提供新的宿主导疗法.
科学领域:
- 肺部医学 肺部医学
- 免疫学 免疫学 免疫学
- 微生物学 微生物学
背景情况:
- 肺炎链球菌 (Streptococcus pneumoniae) (Sp) 引起肺炎,并且可以扩散,导致致命的全身感染.
- 疫苗有效性有限和抗菌素耐药性需要针对Sp诱导炎症的新型宿主导疗法.
- 多态核白细胞 (PMNs) 对于感染控制至关重要,但也会加剧组织损伤和病原体传播.
研究的目的:
- 为了研究12-氧化酶 (12-LOX) 途径依赖性炎症如何促进从肺部传播Sp.
- 为了确定涉及Sp诱导的上皮质屏障突破和全身传播的特定炎症媒介.
主要方法:
- 利用支气管干细胞衍生的空气-液体接口培养物来建模肺上皮.
- 评估了素A3甲基 (HXA3-ME) 和N-formyl-L-methionyl-L-leucyl-phenylalanine (fMLP) 在PMN转移和上皮屏障完整性中的作用.
- 测量中性粒细胞弹性酶 (NE) 从感染了Sp的PMN释放.
- 在小鼠肺炎模型中评估了药理学阻断NE对上皮质干扰和细菌病的影响.
主要成果:
- HXA3-ME,但不是fMLP,诱导PMN转移,上皮单层破坏,并在体外破坏Sp屏障.
- HXA3-ME显著增加了中性粒细胞弹性酶 (NE) 从感染Sp的PMN释放.
- 药理上抑制NE分泌或活性,减少了与Sp.挑战的小鼠上皮质屏障破坏和细菌病的发生.
- 12-LOX通路及其产物HXA3对于Sp的传播至关重要.
结论:
- 肝素A3促进屏障破坏的PMN转移和NE释放,有助于Sp系统性疾病.
- 向HXA3介导的炎症或NE活动代表了肺炎球菌肺炎潜在的宿主导治疗策略.
- 这项研究确定了一种新的机制,通过该机制,Sp利用宿主炎症途径来促进系统性传播.
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