PDF(Pubmed)
Abstract：
BACKGROUND: Pseudomonas aeruginosa (PA) is an opportunistic pathogen that can cause sight threatening infections in the eye and fatal infections in the cystic fibrosis airway. Extracellular vesicles (EVs) are released by host cells during infection and by the bacteria themselves; however, there are no studies on the composition and functional role of host-derived EVs during PA infection of the eye or lung. Here we investigated the composition and capacity of EVs released by PA infected epithelial cells to modulate innate immune responses in host cells.
METHODS: Human telomerase immortalized corneal epithelial cells (hTCEpi) cells and human telomerase immortalized bronchial epithelial cells (HBECs) were treated with a standard invasive test strain of Pseudomonas aeruginosa, PAO1, for 6 h. Host derived EVs were isolated by qEV size exclusion chromatography. EV proteomic profiles during infection were compared using mass spectrometry and functional studies were carried out using hTCEpi cells, HBECs, differentiated neutrophil-like HL-60 cells, and primary human neutrophils isolated from peripheral blood.
RESULTS: EVs released from PA infected corneal epithelial cells increased pro-inflammatory cytokine production in naïve corneal epithelial cells and induced neutrophil chemotaxis independent of cytokine production. The EVs released from PA infected bronchial epithelial cells were also chemotactic although they failed to induce cytokine secretion from naïve HBECs. At the proteomic level, EVs derived from PA infected corneal epithelial cells exhibited lower complexity compared to bronchial epithelial cells, with the latter having reduced protein expression compared to the non-infected control.
CONCLUSIONS: This is the first study to comprehensively profile EVs released by corneal and bronchial epithelial cells during Pseudomonas infection. Together, these findings show that EVs released by PA infected corneal and bronchial epithelial cells function as potent mediators of neutrophil migration, contributing to the exuberant neutrophil response that occurs during infection in these tissues.
METHODS: Human telomerase immortalized corneal epithelial cells (hTCEpi) cells and human telomerase immortalized bronchial epithelial cells (HBECs) were treated with a standard invasive test strain of Pseudomonas aeruginosa, PAO1, for 6 h. Host derived EVs were isolated by qEV size exclusion chromatography. EV proteomic profiles during infection were compared using mass spectrometry and functional studies were carried out using hTCEpi cells, HBECs, differentiated neutrophil-like HL-60 cells, and primary human neutrophils isolated from peripheral blood.
RESULTS: EVs released from PA infected corneal epithelial cells increased pro-inflammatory cytokine production in naïve corneal epithelial cells and induced neutrophil chemotaxis independent of cytokine production. The EVs released from PA infected bronchial epithelial cells were also chemotactic although they failed to induce cytokine secretion from naïve HBECs. At the proteomic level, EVs derived from PA infected corneal epithelial cells exhibited lower complexity compared to bronchial epithelial cells, with the latter having reduced protein expression compared to the non-infected control.
CONCLUSIONS: This is the first study to comprehensively profile EVs released by corneal and bronchial epithelial cells during Pseudomonas infection. Together, these findings show that EVs released by PA infected corneal and bronchial epithelial cells function as potent mediators of neutrophil migration, contributing to the exuberant neutrophil response that occurs during infection in these tissues.
摘要：
背景：铜绿假单胞菌（PA）是一种机会性病原体，可引起眼睛中威胁视力的感染和囊性纤维化气道中的致命感染。细胞外囊泡（EV）在感染过程中由宿主细胞和细菌本身释放；然而，没有关于宿主来源的EV在PA感染眼或肺期间的组成和功能作用的研究。在这里，我们研究了由PA感染的上皮细胞释放的EV的组成和能力，以调节宿主细胞中的先天免疫应答。
方法：人端粒酶永生化角膜上皮细胞（hTCEpi）细胞和人端粒酶永生化支气管上皮细胞（HBECs）用铜绿假单胞菌标准侵袭性试验菌株处理，PAO1,持续6小时。通过qEV尺寸排阻色谱法分离宿主来源的EV。使用质谱比较感染期间的EV蛋白质组谱，并使用hTCEpi细胞进行功能研究，HBEC,分化的中性粒细胞样HL-60细胞，和从外周血中分离的原代人嗜中性粒细胞。
结果：PA感染的角膜上皮细胞释放的EV增加了原始角膜上皮细胞中促炎细胞因子的产生，并诱导了中性粒细胞的趋化性，而与细胞因子的产生无关。从PA感染的支气管上皮细胞释放的EV也具有趋化性，尽管它们未能诱导幼稚HBEC的细胞因子分泌。在蛋白质组层面,与支气管上皮细胞相比，来自PA感染的角膜上皮细胞的EV表现出更低的复杂性，与未感染的对照相比,后者具有降低的蛋白质表达。
结论：这是第一项全面分析假单胞菌感染期间角膜和支气管上皮细胞释放的电动汽车的研究。一起,这些发现表明，由PA感染的角膜和支气管上皮细胞释放的EV作为中性粒细胞迁移的有效介质，有助于这些组织感染期间发生的嗜中性粒细胞反应旺盛。
方法：人端粒酶永生化角膜上皮细胞（hTCEpi）细胞和人端粒酶永生化支气管上皮细胞（HBECs）用铜绿假单胞菌标准侵袭性试验菌株处理，PAO1,持续6小时。通过qEV尺寸排阻色谱法分离宿主来源的EV。使用质谱比较感染期间的EV蛋白质组谱，并使用hTCEpi细胞进行功能研究，HBEC,分化的中性粒细胞样HL-60细胞，和从外周血中分离的原代人嗜中性粒细胞。
结果：PA感染的角膜上皮细胞释放的EV增加了原始角膜上皮细胞中促炎细胞因子的产生，并诱导了中性粒细胞的趋化性，而与细胞因子的产生无关。从PA感染的支气管上皮细胞释放的EV也具有趋化性，尽管它们未能诱导幼稚HBEC的细胞因子分泌。在蛋白质组层面,与支气管上皮细胞相比，来自PA感染的角膜上皮细胞的EV表现出更低的复杂性，与未感染的对照相比,后者具有降低的蛋白质表达。
结论：这是第一项全面分析假单胞菌感染期间角膜和支气管上皮细胞释放的电动汽车的研究。一起,这些发现表明，由PA感染的角膜和支气管上皮细胞释放的EV作为中性粒细胞迁移的有效介质，有助于这些组织感染期间发生的嗜中性粒细胞反应旺盛。
