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Park H, Harmalkar DS, Wei JD, Sun S, Kwon J, Lee CH, Song JG, Park JM, Lee JW, Ahn KS, Han HK, Kim JH, Lee K, Choi Y. Discovery of a novel BLT2 antagonist for the treatment of inflammatory airway diseases. Eur J Med Chem 2023; 261:115864. [PMID: 37839347 DOI: 10.1016/j.ejmech.2023.115864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 10/06/2023] [Accepted: 10/06/2023] [Indexed: 10/17/2023]
Abstract
Leukotriene B4 (LTB4) is a potent chemoattractant that can recruit and activate immune cells such as neutrophils, eosinophils, and monocytes to sites of inflammation. Excessive production of LTB4 has been linked to acute and chronic inflammatory diseases, including asthma, rheumatoid arthritis, and psoriasis. Inhibiting the binding of LTB4 to its receptors, BLT1 and BLT2, is a potential strategy for treating these conditions. While several BLT1 antagonists have been developed for clinical trials, most have failed due to efficacy and safety issues. Therefore, discovering selective BLT2 antagonists could improve our understanding of the distinct functions of BLT1 and BLT2 receptors and their pharmacological implications. In this study, we aimed to discover novel BLT2 antagonists by synthesizing a series of biphenyl analogues based on a BLT2 selective agonist, CAY10583. Among the synthesized compounds, 15b was found to selectively inhibit the chemotaxis of CHO-BLT2 cells with an IC50 value of 224 nM without inhibiting the chemotaxis of CHO-BLT1 cells. 15b also inhibited the binding of LTB4 and BLT2 with a Ki value of 132 nM. Furthermore, 15b had good metabolic stability in liver microsomes and moderate bioavailability (F = 34%) in in vivo PK studies. 15b also showed in vivo efficacy in a mouse model of asthma, reducing airway hyperresponsiveness by 59% and decreasing Th2 cytokines by up to 46%. Our study provides a promising lead for the development of selective BLT2 antagonists as potential therapeutics for inflammatory airway diseases such as asthma and chronic obstructive pulmonary disease.
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Affiliation(s)
- Hyejun Park
- College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Republic of Korea
| | - Dipesh S Harmalkar
- College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Republic of Korea; College of Pharmacy, Dongguk University-Seoul, Goyang, 10326, Republic of Korea; Department of Chemistry, Government College of Arts, Science, and Commerce, Sanquelim, Goa, 403505, India
| | - Jun-Dong Wei
- Department of Basic Medical Science, Medical College, Taizhou University, Taizhou, China
| | - Seunghan Sun
- College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Republic of Korea
| | - Jinsun Kwon
- College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Republic of Korea
| | - Chang Hoon Lee
- College of Pharmacy, Dongguk University-Seoul, Goyang, 10326, Republic of Korea
| | - Jae Geun Song
- College of Pharmacy, Dongguk University-Seoul, Goyang, 10326, Republic of Korea
| | - Jin-Mi Park
- Natural Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology, Ochang, Chungcheongbuk-do, Cheongju, 28116, Republic of Korea
| | - Jae-Won Lee
- Natural Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology, Ochang, Chungcheongbuk-do, Cheongju, 28116, Republic of Korea
| | - Kyung-Seop Ahn
- Natural Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology, Ochang, Chungcheongbuk-do, Cheongju, 28116, Republic of Korea
| | - Hyo-Kyung Han
- College of Pharmacy, Dongguk University-Seoul, Goyang, 10326, Republic of Korea
| | - Jae-Hong Kim
- College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Republic of Korea
| | - Kyeong Lee
- College of Pharmacy, Dongguk University-Seoul, Goyang, 10326, Republic of Korea.
| | - Yongseok Choi
- College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Republic of Korea.
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Kwak DW, Park D, Kim JH. Leukotriene B 4 Receptor 2 Mediates the Production of G-CSF That Plays a Critical Role in Steroid-Resistant Neutrophilic Airway Inflammation. Biomedicines 2022; 10:biomedicines10112979. [PMID: 36428547 PMCID: PMC9687517 DOI: 10.3390/biomedicines10112979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/17/2022] [Accepted: 11/17/2022] [Indexed: 11/22/2022] Open
Abstract
Granulocyte colony-stimulating factor (G-CSF) has been suggested to be closely associated with neutrophilic asthma pathogenesis. However, little is known about the factors regulating the production of G-CSF in neutrophilic asthma. We previously reported that a leukotriene B4 receptor 2, BLT2, played an important role in neutrophilic airway inflammation. Therefore, in the current study, we investigated whether BLT2 plays a role in the production of G-CSF in lipopolysaccharide/ovalbumin (LPS/OVA)-induced steroid-resistant neutrophilic asthma. The data showed that BLT2 critically mediated G-CSF production, contributing to the progression of neutrophilic airway inflammation. We also observed that 12-lipoxygenase (12-LO), which catalyzes the synthesis of the BLT2 ligand 12(S)-HETE, was also necessary for G-CSF production. Together, these results suggest that the 12-LO-BLT2-linked signaling network is critical for the production of G-CSF, contributing to the development of neutrophilic airway inflammation. Our findings can provide a potential new target for the therapy of severe neutrophilic asthma.
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Affiliation(s)
- Dong-Wook Kwak
- Department of Biotechnology, College of Life Sciences, Korea University, Seoul 02841, Republic of Korea
| | - Donghwan Park
- Department of Biotechnology, College of Life Sciences, Korea University, Seoul 02841, Republic of Korea
| | - Jae-Hong Kim
- Department of Life Sciences, College of Life Sciences, Korea University, Seoul 02841, Republic of Korea
- Correspondence: ; Tel.: +82-2-3290-3452
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Leukotriene B4 receptor-2 contributes to KRAS-driven lung tumor formation by promoting interleukin-6-mediated inflammation. Exp Mol Med 2021; 53:1559-1568. [PMID: 34635780 PMCID: PMC8569214 DOI: 10.1038/s12276-021-00682-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 06/17/2021] [Accepted: 08/08/2021] [Indexed: 12/13/2022] Open
Abstract
Although lung cancer is the leading cause of cancer-related deaths worldwide and KRAS is the most frequently mutated oncogene in lung cancer cases, the mechanism by which KRAS mutation drives lung cancer has not been fully elucidated. Here, we report that the expression levels of leukotriene B4 receptor-2 (BLT2) and its ligand-producing enzymes (5-LOX, 12-LOX) were highly increased by mutant KRAS and that BLT2 or 5-/12-LOX blockade attenuated KRAS-driven lung cell proliferation and production of interleukin-6 (IL-6), a principal proinflammatory mediator of lung cancer development. Next, we explored the roles of BLT2 and 5-/12-LOX in transgenic mice with lung-specific expression of mutant KRAS (KrasG12D) and observed that BLT2 or 5-/12-LOX inhibition decreased IL-6 production and tumor formation. To further determine whether BLT2 is involved in KRAS-driven lung tumor formation, we established a KrasG12D/BLT2-KO double-mutant mouse model. In the double-mutant mice, we observed significantly suppressed IL-6 production and lung tumor formation. Additionally, we observed high BLT2 expression in tissue samples from patients with KrasG12D-expressing lung adenocarcinoma, supporting the contributory role of BLT2 in KRAS-driven human lung cancer. Collectively, our results suggest that BLT2 is a potential contributor to KRAS-driven lung cancer and identify an attractive therapeutic target for KRAS-driven lung cancer.
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Park D, Kwak DW, Kim JH. Leukotriene B 4 receptors contribute to house dust mite-induced eosinophilic airway inflammation via T H2 cytokine production. BMB Rep 2021. [PMID: 33612149 PMCID: PMC8016659 DOI: 10.5483/bmbrep.2021.54.3.247] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Leukotriene B4 (LTB4) is a lipid mediator of inflammation that is generated from arachidonic acid via the 5-lipoxygenase pathway. Previous studies have reported that the receptors of LTB4, BLT1, and BLT2 play mediatory roles in the allergic airway inflammation induced by ovalbumin (OVA). However, considering that house dust mites (HDMs) are the most prevalent allergen and well-known risk factor for asthmatic allergies, we are interested in elucidating the contributory roles of BLT1/2 in HDM-induced allergic airway inflammation. Our aim in this study was to investigate whether BLT1/2 play any roles in HDM-induced allergic airway inflammation. In this study, we observed that the levels of ligands for BLT1/2 [LTB4 and 12(S)-HETE (12(S)-hydroxyeicosatetraenoic acid)] were significantly increased in bronchoalveolar lavage fluid (BALF) after HDM challenge. Block-ade of BLT1 or BLT2 as well as of 5-lipoxygenase (5-LO) or 12-lipoxygenase (12-LO) markedly suppressed the production of TH2 cytokines (IL-4, IL-5, and IL-13) and alleviated lung inflammation and mucus secretion in an HDM-induced eosinophilic airway-inflammation mouse model. Together, these results indicate that the 5-/12-LO-BLT1/2 cascade plays a role in HDM-induced airway inflammation by mediating the production of TH2 cytokines. Our findings suggest that BLT1/2 may be a potential therapeutic target for patients with HDM-induced allergic asthma.
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Affiliation(s)
- Donghwan Park
- Department of Biotechnology, College of Life Sciences, Korea University, Seoul 02841, Korea
| | - Dong-Wook Kwak
- Department of Biotechnology, College of Life Sciences, Korea University, Seoul 02841, Korea
| | - Jae-Hong Kim
- Department of Life Sciences, College of Life Sciences, Korea University, Seoul 02841, Korea
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Role of Leukotriene B 4 Receptor-2 in Mast Cells in Allergic Airway Inflammation. Int J Mol Sci 2019; 20:ijms20122897. [PMID: 31197082 PMCID: PMC6627931 DOI: 10.3390/ijms20122897] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 06/12/2019] [Accepted: 06/12/2019] [Indexed: 12/28/2022] Open
Abstract
Mast cells are effector cells in the immune system that play an important role in the allergic airway inflammation. Recently, it was reported that BLT2, a low-affinity leukotriene (LT) B4 receptor, plays a pivotal role in the pathogenesis of allergic airway inflammation through its action in mast cells. We observed that highly elevated expression levels of BLT2 are critical for the pathogenesis leading to allergic airway inflammation, and that if BLT2 expression is downregulated by siBLT2-mediated knockdown, allergic inflammation is dramatically alleviated. Furthermore, we demonstrated that BLT2 mediates the synthesis of vascular endothelial growth factor (VEGF) and Th2 cytokines, such as interleukin (IL)-13, in mast cells during allergic inflammation. Based on the critical roles of BLT2 in mast cells in allergic inflammation, anti-BLT2 strategies could contribute to the development of new therapies for allergic airway inflammation.
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Abebayehu D, Spence AJ, Caslin H, Taruselli M, Haque TT, Kiwanuka KN, Kolawole EM, Chumanevich AP, Sell SA, Oskeritzian CA, Ryan J, Kee SA. Lactic acid suppresses IgE-mediated mast cell function in vitro and in vivo. Cell Immunol 2019; 341:103918. [PMID: 31030957 DOI: 10.1016/j.cellimm.2019.04.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 03/21/2019] [Accepted: 04/11/2019] [Indexed: 02/07/2023]
Abstract
Mast cells have functional plasticity affected by their tissue microenvironment, which greatly impacts their inflammatory responses. Because lactic acid (LA) is abundant in inflamed tissues and tumors, we investigated how it affects mast cell function. Using IgE-mediated activation as a model system, we found that LA suppressed inflammatory cytokine production and degranulation in mouse peritoneal mast cells, data that were confirmed with human skin mast cells. In mouse peritoneal mast cells, LA-mediated cytokine suppression was dependent on pH- and monocarboxylic transporter-1 expression. Additionally, LA reduced IgE-induced Syk, Btk, and ERK phosphorylation, key signals eliciting inflammation. In vivo, LA injection reduced IgE-mediated hypothermia in mice undergoing passive systemic anaphylaxis. Our data suggest that LA may serve as a feedback inhibitor that limits mast cell-mediated inflammation.
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Affiliation(s)
- Daniel Abebayehu
- Department of Biology, Virginia Commonwealth University, Richmond, VA 23284-2012, United States
| | - Andrew J Spence
- Department of Biology, Virginia Commonwealth University, Richmond, VA 23284-2012, United States
| | - Heather Caslin
- Department of Biology, Virginia Commonwealth University, Richmond, VA 23284-2012, United States
| | - Marcela Taruselli
- Department of Biology, Virginia Commonwealth University, Richmond, VA 23284-2012, United States
| | - Tamara T Haque
- Department of Biology, Virginia Commonwealth University, Richmond, VA 23284-2012, United States
| | - Kasalina N Kiwanuka
- Department of Biology, Virginia Commonwealth University, Richmond, VA 23284-2012, United States
| | | | - Alena P Chumanevich
- Department of Pathology, Microbiology & Immunology, University of South Carolina School of Medicine, Columbia, SC 29208, United States
| | - Scott A Sell
- Department of Biomedical Engineering, Parks College of Engineering, Aviation and Technology, Saint Louis University, St. Louis, MO 63103, United States
| | - Carole A Oskeritzian
- Department of Pathology, Microbiology & Immunology, University of South Carolina School of Medicine, Columbia, SC 29208, United States
| | - John Ryan
- Department of Biology, Virginia Commonwealth University, Richmond, VA 23284-2012, United States.
| | - Sydney Ann Kee
- Department of Biology, Virginia Commonwealth University, Richmond, VA 23284-2012, United States
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Robida PA, Puzzovio PG, Pahima H, Levi-Schaffer F, Bochner BS. Human eosinophils and mast cells: Birds of a feather flock together. Immunol Rev 2019; 282:151-167. [PMID: 29431215 DOI: 10.1111/imr.12638] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
While the origin of the phrase "birds of a feather flock together" is unclear, it has been in use for centuries and is typically employed to describe the phenomenon that people with similar tastes or interests tend to seek each other out and congregate together. In this review, we have co-opted this phrase to compare innate immune cells of related origin, the eosinophil and mast cell, because they very often accumulate together in tissue sites under both homeostatic and inflammatory conditions. To highlight overlapping yet distinct features, their hematopoietic development, cell surface phenotype, mediator release profiles and roles in diseases have been compared and contrasted. What emerges is a sense that these two cell types often interact with each other and their tissue environment to provide synergistic contributions to a variety of normal and pathologic immune responses.
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Affiliation(s)
- Piper A Robida
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Pier Giorgio Puzzovio
- Pharmacology and Experimental Therapeutics Unit, School of Pharmacy, Institute for Drug Research, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Hadas Pahima
- Pharmacology and Experimental Therapeutics Unit, School of Pharmacy, Institute for Drug Research, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Francesca Levi-Schaffer
- Pharmacology and Experimental Therapeutics Unit, School of Pharmacy, Institute for Drug Research, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Bruce S Bochner
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
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Ro M, Lee AJ, Kim JH. 5-/12-Lipoxygenase-linked cascade contributes to the IL-33-induced synthesis of IL-13 in mast cells, thus promoting asthma development. Allergy 2018; 73:350-360. [PMID: 28857185 DOI: 10.1111/all.13294] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/23/2017] [Indexed: 12/31/2022]
Abstract
BACKGROUND As asthma progresses, the levels of IL-33 in serum are markedly increased and contribute to asthmatic development and exacerbation. Mast cells, one of the principal effector cells in the pathogenesis of asthma, express high levels of the IL-33 receptor ST2 and have been shown to be activated by IL-33. Thus, IL-33 stimulates mast cells to produce Th2-type cytokines such as IL-13, thus contributing to asthmatic development. However, the signaling mechanism for IL-33-induced synthesis of Th2 cytokines, particularly IL-13, has not been fully elucidated in mast cells. METHODS The role of 5- or 12-LO in the IL-33-induced synthesis of IL-13 was investigated using knockdown or pharmacological inhibitors in bone marrow-derived mast cells (BMMCs) and animal model. RESULTS Blockade of 5- or 12-LO significantly suppressed IL-33-induced synthesis of IL-13 in BMMCs. The subsequent action of 5- and 12-LO metabolites through their specific receptor, BLT2, was also critical for IL-33-induced synthesis of IL-13. We also demonstrated that the MyD88-p38 kinase cascade lies upstream of 5-/12-LO and that NF-κB lies downstream of 5-/12-LO to mediate the IL-33-induced synthesis of IL-13 in mast cells. Consistent with these findings, we observed that in an IL-33-administered asthmatic airway inflammation model, IL-13 levels were markedly increased in bronchoalveolar lavage fluid, but its levels were markedly suppressed by treatment with inhibitors of 5-LO, 12-LO or BLT2, further suggesting roles of 5-/12-LO in IL-33-induced IL-13 production. CONCLUSION Our results suggest that "MyD88-5-/12-LO-BLT2-NF-κB" cascade significantly contributes to the IL-33-induced synthesis of IL-13 in mast cells, thus potentially contributing to asthmatic development and exacerbation.
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Affiliation(s)
- MyungJa Ro
- School of Life Sciences and Biotechnology; Korea University; Seoul Korea
| | - A-Jin Lee
- School of Life Sciences and Biotechnology; Korea University; Seoul Korea
| | - Jae-Hong Kim
- School of Life Sciences and Biotechnology; Korea University; Seoul Korea
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Lee AJ, Ro M, Cho KJ, Kim JH. Lipopolysaccharide/TLR4 Stimulates IL-13 Production through a MyD88-BLT2-Linked Cascade in Mast Cells, Potentially Contributing to the Allergic Response. THE JOURNAL OF IMMUNOLOGY 2017; 199:409-417. [PMID: 28600286 DOI: 10.4049/jimmunol.1602062] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 05/08/2017] [Indexed: 01/26/2023]
Abstract
In an experimental asthma model, the activation of TLR4 by bacterial LPS occasionally exacerbates allergic inflammation through the production of Th2 cytokines, and mast cells have been suggested to play a central role in this response. However, the detailed mechanism underlying how LPS/TLR4 stimulates the production of Th2 cytokines, especially IL-13, remains unclear in mast cells. In the current study, we observed that the expression levels of leukotriene B4 receptor-2 (BLT2) and the synthesis of its ligands were highly upregulated in LPS-stimulated bone marrow-derived mast cells and that BLT2 blockade with small interfering RNA or a pharmacological inhibitor completely abolished IL-13 production, suggesting a mediatory role of the BLT2 ligand-BLT2 axis in LPS/TLR4 signaling to IL-13 synthesis in mast cells. Moreover, we demonstrated that MyD88 lies upstream of the BLT2 ligand-BLT2 axis and that this MyD88-BLT2 cascade leads to the generation of reactive oxygen species through NADPH oxidase 1 and the subsequent activation of NF-κB, thereby mediating IL-13 synthesis. Interestingly, we observed that costimulation of LPS/TLR4 and IgE/FcεRI caused greatly enhanced IL-13 synthesis in mast cells, and blockading BLT2 abolished these effects. Similarly, in vivo, the IL-13 level was markedly enhanced by LPS administration in an OVA-induced asthma model, and injecting a BLT2 antagonist beforehand clearly attenuated this increase. Together, our findings suggest that a BLT2-linked cascade plays a pivotal role in LPS/TLR4 signaling for IL-13 synthesis in mast cells, thereby potentially exacerbating allergic response. Our findings may provide insight into the mechanisms underlying how bacterial infection worsens allergic inflammation under certain conditions.
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Affiliation(s)
- A-Jin Lee
- College of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea; and
| | - MyungJa Ro
- College of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea; and
| | - Kyung-Jin Cho
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Jae-Hong Kim
- College of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea; and
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Lv J, Xiong Y, Li W, Yang W, Zhao L, He R. BLT1 Mediates Bleomycin-Induced Lung Fibrosis Independently of Neutrophils and CD4+ T Cells. THE JOURNAL OF IMMUNOLOGY 2017; 198:1673-1684. [PMID: 28077599 DOI: 10.4049/jimmunol.1600465] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 12/12/2016] [Indexed: 02/04/2023]
Abstract
Leukotriene B4 (LTB4) and its functional receptor BLT1 are closely involved in tissue inflammation by primarily mediating leukocyte recruitment and activation. Elevated LTB4 was reported in patients with lung fibrosis; however, the role of the LTB4/BLT1 axis in lung fibrosis remains unknown. In this study, we demonstrated that BLT1-/- mice exhibited significantly attenuated bleomycin (BLM)-induced lung fibrosis. Interestingly, BLT1 blockade with its specific antagonist U75302 in the acute injury phase (days 0-10 after BLM treatment) significantly attenuated lung fibrosis, which was accompanied by significant decreases in early infiltrating neutrophils and later infiltrating CD4+ T cells and the production of TGF-β, IL-13, and IL-17A. In contrast, BLT1 blockade in the fibrotic phase (days 10-21 after BLM treatment) had no effect on lung fibrosis and TGF-β production, although it significantly decreased CD4+ T cell infiltration. Furthermore, depletion of neutrophils or CD4+ T cells had no effect on BLM-induced lung fibrosis, suggesting the independence of profibrotic activity of the LTB4/BLT1 axis on BLT1-dependent lung recruitment of these two leukocytes. Finally, although BLT1 blockade had no effect on the recruitment and phenotype of macrophages in BLM-induced lung fibrosis, the LTB4/BLT1 axis could promote TGF-β production by macrophages stimulated with BLM or supernatants from BLM-exposed airway epithelial cells in an autocrine manner, which further induced collagen secretion by lung fibroblasts. Collectively, our study demonstrates that the LTB4/BLT1 axis plays a critical role in acute injury phase to promote BLM-induced lung fibrosis, and it suggests that early interruption of the LTB4/BLT1 axis in some inflammatory diseases could prevent the later development of tissue fibrosis.
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Affiliation(s)
- Jiaoyan Lv
- Department of Immunology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, People's Republic of China; and.,Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, School of Basic Medical Sciences, Fudan University, Shanghai 200032, People's Republic of China
| | - Yingluo Xiong
- Department of Immunology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, People's Republic of China; and.,Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, School of Basic Medical Sciences, Fudan University, Shanghai 200032, People's Republic of China
| | - Wenjing Li
- Department of Immunology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, People's Republic of China; and.,Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, School of Basic Medical Sciences, Fudan University, Shanghai 200032, People's Republic of China
| | - Wei Yang
- Department of Immunology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, People's Republic of China; and.,Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, School of Basic Medical Sciences, Fudan University, Shanghai 200032, People's Republic of China
| | - Lina Zhao
- Department of Immunology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, People's Republic of China; and.,Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, School of Basic Medical Sciences, Fudan University, Shanghai 200032, People's Republic of China
| | - Rui He
- Department of Immunology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, People's Republic of China; and .,Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, School of Basic Medical Sciences, Fudan University, Shanghai 200032, People's Republic of China
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