单位:[1]Univ Illinois, Coll Med, Dept Anesthesiol, Chicago, IL 60680 USA[2]Univ Illinois, Coll Med, Dept Pharmacol & Regenerat Med, Chicago, IL 60680 USA[3]Capital Med Univ, Beijing Friendship Hosp, Dept Anesthesiol, Beijing, Peoples R China临床科室麻醉科麻醉科首都医科大学附属北京友谊医院[4]Changhai Hosp, Fac Anesthesiol, Shanghai, Peoples R China[5]Ann & Robert H Lurie Childrens Hosp Chicago, Stanley Manne Childrens Res Inst, Program Lung & Vasc Biol, Chicago, IL 60611 USA[6]Northwestern Univ, Dept Pediat, Feinberg Sch Med, Div Crit Care, Chicago, IL 60611 USA
Mechanical ventilation is a life-sustaining therapy for patients with respiratory failure but can cause further lung damage known as ventilator-induced lung injury (VILI). However, the intrinsic molecular mechanisms underlying recovery of VILI remain unknown. Phagocytosis of apoptotic cells (also known as efferocytosis) is a key mechanism orchestrating successful resolution of inflammation. Here we show the positive regulation of macrophage Toll-like receptor (TLR) 4 in efferocytosis and resolution of VILI. Mice were depleted of alveolar macrophages and then subjected to injurious ventilation (tidal volume, 20 mL/kg) for 4 h. On day 1 after mechanical ventilation, Tlr4(+/+) or Tlr4(-/-) bone marrow-derived macrophages (BMDMs) were intratracheally administered to alveolar macrophage-depleted mice. We observed that mice depleted of alveolar macrophages exhibited defective resolution of neutrophilic inflammation, exuded protein, lung edema, and lung tissue injury after ventilation, whereas these delayed responses were reversed by administration of Tlr4(+/+) BMDMs. Importantly, these proresolving effects by Tlr4(+/+) BMDMs were abolished in mice receiving Tlr4(-/-) BMDMs. The number of macrophages containing apoptotic cells or bodies in bronchoalveolar lavage fluid was much less in mice receiving Tlr4(-/-) BMDMs than that in those receiving Tlr4(+/+) BMDMs. Macrophage TLR4 deletion facilitated a disintegrin and metalloprotease 17 maturation and enhanced Mer cleavage in response to mechanical ventilation. Heat shock protein 70 dramatically increased Mer tyrosine kinase surface expression, phagocytosis of apoptotic neutrophils, and rescued the inflammatory phenotype in alveolar macrophage-depleted mice receiving Tlr4(+/+) BMDMs, but not Tlr4(-/-) BMDMs. Our results suggest that macrophage TLR4 promotes resolution of VILI via modulation of Mer-mediated efferocytosis.
基金:
National Heart, Lung, and Blood Institute of the National Institutes of HealthUnited States Department of Health & Human ServicesNational Institutes of Health (NIH) - USANIH National Heart Lung & Blood Institute (NHLBI) [R01HL152696, R01HL104092]; National Institute of Allergy and Infectious Diseases of the National Institutes of HealthUnited States Department of Health & Human ServicesNational Institutes of Health (NIH) - USANIH National Institute of Allergy & Infectious Diseases (NIAID) [R21AI152249]
第一作者单位:[1]Univ Illinois, Coll Med, Dept Anesthesiol, Chicago, IL 60680 USA[3]Capital Med Univ, Beijing Friendship Hosp, Dept Anesthesiol, Beijing, Peoples R China
通讯作者:
通讯机构:[1]Univ Illinois, Coll Med, Dept Anesthesiol, Chicago, IL 60680 USA[2]Univ Illinois, Coll Med, Dept Pharmacol & Regenerat Med, Chicago, IL 60680 USA
推荐引用方式(GB/T 7714):
Su Kai,Bo Lulong,Jiang Chunling,et al.TLR4 is required for macrophage efferocytosis during resolution of ventilator-induced lung injury[J].AMERICAN JOURNAL of PHYSIOLOGY-LUNG CELLULAR and MOLECULAR PHYSIOLOGY.2021,321(4):L787-L801.doi:10.1152/ajplung.00226.2021.
APA:
Su, Kai,Bo, Lulong,Jiang, Chunling,Deng, Xiaoming,Zhao, You-Yang...&Hu, Guochang.(2021).TLR4 is required for macrophage efferocytosis during resolution of ventilator-induced lung injury.AMERICAN JOURNAL of PHYSIOLOGY-LUNG CELLULAR and MOLECULAR PHYSIOLOGY,321,(4)
MLA:
Su, Kai,et al."TLR4 is required for macrophage efferocytosis during resolution of ventilator-induced lung injury".AMERICAN JOURNAL of PHYSIOLOGY-LUNG CELLULAR and MOLECULAR PHYSIOLOGY 321..4(2021):L787-L801