1
|
Xin Y, Xiong S, Zhou L, Lin X. Activation of leukotriene B 4 receptor 1 is a prerequisite for complement receptor 3-mediated antifungal responses of neutrophils. Cell Mol Immunol 2024; 21:245-259. [PMID: 38297112 PMCID: PMC10901876 DOI: 10.1038/s41423-024-01130-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 12/31/2023] [Indexed: 02/02/2024] Open
Abstract
Invasive fungal infections are life-threatening, and neutrophils are vital cells of the innate immune system that defend against them. The role of LTA4H-LTB4-BLT1 axis in regulation of neutrophil responses to fungal infection remains poorly understood. Here, we demonstrated that the LTA4H-LTB4-BLT1 axis protects the host against Candida albicans and Aspergillus fumigatus, but not Cryptococcus neoformans infection, by regulating the antifungal activity of neutrophils. Our results show that deleting Lta4h or Blt1 substantially impairs the fungal-specific phagocytic capacity of neutrophils. Moreover, defective activation of the spleen tyrosine kinase (Syk) and extracellular signal-related kinase (ERK1/2) pathways in neutrophils accompanies this impairment. Mechanistically, BLT1 regulates CR3-mediated, β-1,3-glucan-induced neutrophil phagocytosis, while a physical interaction with CR3 with slight influence on its dynamics is observed. Our findings thus demonstrate that the LTA4H-LTB4-BLT1 axis is essential for the phagocytic function of neutrophils in host antifungal immune response against Candida albicans and Aspergillus fumigatus.
Collapse
Affiliation(s)
- Yan Xin
- Institute for Immunology and School of Medicine, Tsinghua University, 100084, Beijing, China
- Tsinghua University-Peking University Center for Life Sciences, 100084, Beijing, China
| | - Sihan Xiong
- Institute for Immunology and School of Medicine, Tsinghua University, 100084, Beijing, China
| | - Linghong Zhou
- Department of Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, National Medical Center for Infectious Diseases, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Xin Lin
- Institute for Immunology and School of Medicine, Tsinghua University, 100084, Beijing, China.
- Tsinghua University-Peking University Center for Life Sciences, 100084, Beijing, China.
| |
Collapse
|
2
|
Park D, Ro M, Lee AJ, Kwak DW, Chung Y, Kim JH. Contributory Role of BLT2 in the Production of Proinflammatory Cytokines in Cecal Ligation and Puncture-Induced Sepsis. Mol Cells 2021; 44:893-899. [PMID: 34887363 PMCID: PMC8718367 DOI: 10.14348/molcells.2021.0159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 10/03/2021] [Accepted: 10/15/2021] [Indexed: 11/27/2022] Open
Abstract
BLT2 is a low-affinity receptor for leukotriene B4, a potent lipid mediator of inflammation generated from arachidonic acid via the 5-lipoxygenase pathway. The aim of this study was to investigate whether BLT2 plays any role in sepsis, a systemic inflammatory response syndrome caused by infection. A murine model of cecal ligation and puncture (CLP)-induced sepsis was used to evaluate the role of BLT2 in septic inflammation. In the present study, we observed that the levels of ligands for BLT2 (LTB4 [leukotriene B4] and 12(S)-HETE [12(S)-hydroxyeicosatetraenoic acid]) were significantly increased in the peritoneal lavage fluid and serum from mice with CLP-induced sepsis. We also observed that the levels of BLT2 as well as 5-LO and 12-LO, which are synthesizing enzymes for LTB4 and 12(S)-HETE, were significantly increased in lung and liver tissues in the CLP mouse model. Blockade of BLT2 markedly suppressed the production of sepsis-associated cytokines (IL-6 [interleukin-6], TNF-α [tumor necrosis factor alpha], and IL-1β [interleukin-1β] as well as IL-17 [interleukin-17]) and alleviated lung inflammation in the CLP group. Taken together, our results suggest that BLT2 cascade contributes to lung inflammation in CLP-induced sepsis by mediating the production of inflammatory cytokines. These findings suggest that BLT2 may be a potential therapeutic target for sepsis patients.
Collapse
Affiliation(s)
- Donghwan Park
- Department of Biotechnology, College of Life Sciences, Korea University, Seoul 02841, Korea
| | - MyungJa Ro
- Department of Biotechnology, College of Life Sciences, Korea University, Seoul 02841, Korea
| | - A-Jin Lee
- 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
| | - Yunro Chung
- College of Health Solutions, Arizona State University, Phoenix, AZ 85004, USA
- Biodesign Center for Personalized Diagnostics, Arizona State University, Tempe, AZ 85281, USA
| | - Jae-Hong Kim
- Division of Life Sciences, College of Life Sciences, Korea University, Seoul 02841, Korea
| |
Collapse
|
3
|
Al-Shaer AE, Buddenbaum N, Shaikh SR. Polyunsaturated fatty acids, specialized pro-resolving mediators, and targeting inflammation resolution in the age of precision nutrition. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:158936. [PMID: 33794384 PMCID: PMC8496879 DOI: 10.1016/j.bbalip.2021.158936] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/17/2021] [Accepted: 03/24/2021] [Indexed: 12/16/2022]
Abstract
Chronic inflammation contributes toward the pathogenesis of numerous diseases including, but not limited to, obesity, autoimmunity, cardiovascular diseases, and cancers. The discovery of specialized pro-resolving mediators (SPMs), which are critical for resolving inflammation, has commenced investigation into targeting pathways of inflammation resolution to improve physiological outcomes. SPMs are predominately synthesized from the n-3 polyunsaturated fatty acids (PUFA) eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. Therefore, one viable strategy to promote inflammation resolution would be to increase dietary intake of EPA/DHA, which are deficient in select populations. However, there are inconsistencies between the use of EPA/DHA as dietary or pharmacological supplements and improved inflammatory status. Herein, we review the literature on the relationship between the high n-6/n-3 PUFA ratio, downstream SPM biosynthesis, and inflammatory endpoints. We highlight key studies that have investigated how dietary intake of EPA/DHA increase tissue SPMs and their effects on inflammation. We also discuss the biochemical pathways by which EPA/DHA drive SPM biosynthesis and underscore mechanistic gaps in knowledge about these pathways which include a neglect for host genetics/ethnic differences in SPM metabolism, sexual dimorphism in SPM levels, and potential competition from select dietary n-6 PUFAs for enzymes of SPM synthesis. Altogether, establishing how dietary PUFAs control SPM biosynthesis in a genetic- and sex-dependent manner will drive new precision nutrition studies with EPA/DHA to prevent chronic inflammation in select populations.
Collapse
Affiliation(s)
- Abrar E Al-Shaer
- Department of Nutrition, Gillings School of Global Public Health and School of Medicine, The University of North Carolina at Chapel Hill, 170 Rosenau Hall, CB# 7400, 135 Dauer Drive, Chapel Hill, NC, USA
| | - Nicole Buddenbaum
- Department of Nutrition, Gillings School of Global Public Health and School of Medicine, The University of North Carolina at Chapel Hill, 170 Rosenau Hall, CB# 7400, 135 Dauer Drive, Chapel Hill, NC, USA
| | - Saame Raza Shaikh
- Department of Nutrition, Gillings School of Global Public Health and School of Medicine, The University of North Carolina at Chapel Hill, 170 Rosenau Hall, CB# 7400, 135 Dauer Drive, Chapel Hill, NC, USA.
| |
Collapse
|
4
|
Blagojević V, Kovačević-Jovanović V, Ćuruvija I, Petrović R, Vujnović I, Vujić V, Stanojević S. Rat strain differences in peritoneal immune cell response to selected gut microbiota: A crossroad between tolerance and autoimmunity? Life Sci 2018; 197:147-157. [DOI: 10.1016/j.lfs.2018.02.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 02/06/2018] [Accepted: 02/07/2018] [Indexed: 02/06/2023]
|
5
|
Sasaki F, Koga T, Saeki K, Okuno T, Kazuno S, Fujimura T, Ohkawa Y, Yokomizo T. Biochemical and immunological characterization of a novel monoclonal antibody against mouse leukotriene B4 receptor 1. PLoS One 2017; 12:e0185133. [PMID: 28922396 PMCID: PMC5602668 DOI: 10.1371/journal.pone.0185133] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 09/05/2017] [Indexed: 01/27/2023] Open
Abstract
Leukotriene B4 (LTB4) receptor 1 (BLT1) is a G protein-coupled receptor expressed in various leukocyte subsets; however, the precise expression of mouse BLT1 (mBLT1) has not been reported because a mBLT1 monoclonal antibody (mAb) has not been available. In this study, we present the successful establishment of a hybridoma cell line (clone 7A8) that produces a high-affinity mAb for mBLT1 by direct immunization of BLT1-deficient mice with mBLT1-overexpressing cells. The specificity of clone 7A8 was confirmed using mBLT1-overexpressing cells and mouse peripheral blood leukocytes that endogenously express BLT1. Clone 7A8 did not cross-react with human BLT1 or other G protein-coupled receptors, including human chemokine (C-X-C motif) receptor 4. The 7A8 mAb binds to the second extracellular loop of mBLT1 and did not affect LTB4 binding or intracellular calcium mobilization by LTB4. The 7A8 mAb positively stained Gr-1-positive granulocytes, CD11b-positive granulocytes/monocytes, F4/80-positive monocytes, CCR2-high and CCR2-low monocyte subsets in the peripheral blood and a CD4-positive T cell subset, Th1 cells differentiated in vitro from naïve CD4-positive T cells. This mAb was able to detect Gr-1-positive granulocytes and monocytes in the spleens of naïve mice by immunohistochemistry. Finally, intraperitoneal administration of 7A8 mAb depleted granulocytes and monocytes in the peripheral blood. We have therefore succeeded in generating a high-affinity anti-mBLT1 mAb that is useful for analyzing mBLT1 expression in vitro and in vivo.
Collapse
MESH Headings
- Animals
- Antibodies, Monoclonal, Murine-Derived/chemistry
- Antibodies, Monoclonal, Murine-Derived/immunology
- Antibodies, Monoclonal, Murine-Derived/pharmacology
- CHO Cells
- Calcium Signaling/drug effects
- Cell Differentiation/immunology
- Cricetinae
- Cricetulus
- Granulocytes/immunology
- Leukotriene B4/immunology
- Male
- Mice
- Mice, Inbred BALB C
- Mice, Knockout
- Monocytes/immunology
- Protein Structure, Secondary
- Receptors, Leukotriene B4/antagonists & inhibitors
- Receptors, Leukotriene B4/chemistry
- Receptors, Leukotriene B4/immunology
- Th1 Cells/immunology
Collapse
Affiliation(s)
- Fumiyuki Sasaki
- Department of Biochemistry, Juntendo University School of Medicine, Tokyo, Japan
| | - Tomoaki Koga
- Department of Biochemistry, Juntendo University School of Medicine, Tokyo, Japan
| | - Kazuko Saeki
- Department of Biochemistry, Juntendo University School of Medicine, Tokyo, Japan
| | - Toshiaki Okuno
- Department of Biochemistry, Juntendo University School of Medicine, Tokyo, Japan
| | - Saiko Kazuno
- Laboratory of Proteomics and Biomolecular Science Research Support Center, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Tsutomu Fujimura
- Laboratory of Bioanalytical Chemistry, Tohoku Medical and Pharmaceutical University, Miyagi, Japan
| | - Yasuyuki Ohkawa
- Division of Transcriptomics, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Takehiko Yokomizo
- Department of Biochemistry, Juntendo University School of Medicine, Tokyo, Japan
- * E-mail:
| |
Collapse
|
6
|
Jala VR, Maturu P, Bodduluri SR, Krishnan E, Mathis S, Subbarao K, Wang M, Jenson AB, Proctor ML, Rouchka EC, Knight R, Haribabu B. Leukotriene B 4-receptor-1 mediated host response shapes gut microbiota and controls colon tumor progression. Oncoimmunology 2017; 6:e1361593. [PMID: 29209564 DOI: 10.1080/2162402x.2017.1361593] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 07/24/2017] [Accepted: 07/26/2017] [Indexed: 02/07/2023] Open
Abstract
Inflammation and infection are key promoters of colon cancer but the molecular interplay between these events is largely unknown. Mice deficient in leukotriene B4 receptor1 (BLT1) are protected in inflammatory disease models of arthritis, asthma and atherosclerosis. In this study, we show that BLT1-/- mice when bred onto a spontaneous tumor (ApcMin/+) model displayed an increase in the rate of intestinal tumor development and mortality. A paradoxical increase in inflammation in the tumors from the BLT1-/-ApcMin/+ mice is coincidental with defective host response to infection. Germ-free BLT1-/-ApcMin/+ mice are free from colon tumors that reappeared upon fecal transplantation. Analysis of microbiota showed defective host response in BLT1-/- ApcMin/+ mice reshapes the gut microbiota to promote colon tumor development. The BLT1-/-MyD88-/- double deficient mice are susceptible to lethal neonatal infections. Broad-spectrum antibiotic treatment eliminated neonatal lethality in BLT1-/-MyD88-/- mice and the BLT1-/-MyD88-/-ApcMin+ mice are protected from colon tumor development. These results identify a novel interplay between the Toll-like receptor mediated microbial sensing mechanisms and BLT1-mediated host response in the control of colon tumor development.
Collapse
Affiliation(s)
- Venkatakrishna R Jala
- James Graham Brown Cancer Center, University of Louisville Health Sciences Center, Louisville, KY, USA.,Department of Microbiology and Immunology, University of Louisville Health Sciences Center, Louisville, KY, USA
| | - Paramahamsa Maturu
- James Graham Brown Cancer Center, University of Louisville Health Sciences Center, Louisville, KY, USA.,Department of Microbiology and Immunology, University of Louisville Health Sciences Center, Louisville, KY, USA
| | - Sobha R Bodduluri
- James Graham Brown Cancer Center, University of Louisville Health Sciences Center, Louisville, KY, USA.,Department of Microbiology and Immunology, University of Louisville Health Sciences Center, Louisville, KY, USA
| | - Elangovan Krishnan
- James Graham Brown Cancer Center, University of Louisville Health Sciences Center, Louisville, KY, USA.,Department of Microbiology and Immunology, University of Louisville Health Sciences Center, Louisville, KY, USA
| | - Steven Mathis
- James Graham Brown Cancer Center, University of Louisville Health Sciences Center, Louisville, KY, USA.,Department of Microbiology and Immunology, University of Louisville Health Sciences Center, Louisville, KY, USA
| | - Krishnaprasad Subbarao
- James Graham Brown Cancer Center, University of Louisville Health Sciences Center, Louisville, KY, USA.,Department of Microbiology and Immunology, University of Louisville Health Sciences Center, Louisville, KY, USA
| | - Min Wang
- James Graham Brown Cancer Center, University of Louisville Health Sciences Center, Louisville, KY, USA.,Department of Microbiology and Immunology, University of Louisville Health Sciences Center, Louisville, KY, USA
| | - Alfred B Jenson
- Department of Pathology, University of Louisville Health Sciences Center, Louisville, KY, USA
| | - Mary L Proctor
- Research Resources Center, University of Louisville Health Sciences Center, Louisville, KY, USA
| | - Eric C Rouchka
- Department of Computer Engineering & Computer Science, Speed School of Engineering, University of Louisville, Louisville, KY, USA
| | - Rob Knight
- Center for Microbiome Innovation, University of California San Diego, La Jolla, CA, USA
| | - Bodduluri Haribabu
- James Graham Brown Cancer Center, University of Louisville Health Sciences Center, Louisville, KY, USA.,Department of Microbiology and Immunology, University of Louisville Health Sciences Center, Louisville, KY, USA
| |
Collapse
|
7
|
Chacon AC, Phillips BE, Chacon MA, Brunke-Reese D, Kelleher SL, Soybel DI. Oral omega-3 fatty acids promote resolution in chemical peritonitis. J Surg Res 2016; 206:190-198. [PMID: 27916361 DOI: 10.1016/j.jss.2016.06.036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 06/01/2016] [Accepted: 06/10/2016] [Indexed: 12/31/2022]
Abstract
BACKGROUND Recent studies suggest that purified omega-3 fatty acids may attenuate acute inflammation and hasten the transition to healing. In this study, we tested the hypothesis that pretreatment with omega-3-rich fish oil (FO) would promote resolution of peritoneal inflammation through production of specific lipid mediators. METHODS C57/BL6 mice were given a daily 200-μL oral gavage of saline (CTL) or FO (1.0-1.5 g/kg/d docosahexaenoic acid and 1.3-2.0 g/kg/d eicosapentaenoic acid) for 7 d before chemical peritonitis was induced with thioglycollate. Peritoneal lavage fluid was collected before induction and at days 2 and 4 after peritonitis onset. Prostaglandin E2 (PGE2), Leukotriene B4 (LTB4), Resolvin D1 (RvD1), and the composition of immune cell populations were examined in peritoneal lavage exudates. Cells harvested from the peritoneum were assessed for macrophage differentiation markers, phagocytosis, and lipopolysaccharide-induced cytokine secretion profiles (interleukin [IL]-6, IL-10, IL-1β, TNFα). RESULTS The ratio of RvD1 to pro-inflammatory PGE2 and LTB4 was increased in the peritoneal cavity of FO-supplemented animals. FO induced a decrease in the number of monocytes in the lavage fluid, with no change in the number of macrophages, neutrophils, or lymphocytes. Macrophage phagocytosis and M1/M2 messenger RNA markers were unchanged by FO with the exception of decreased PPARγ expression. FO increased ex vivo TNFα secretion after stimulation with lipopolysaccharide. CONCLUSIONS Our findings provide evidence that nutraceutically relevant doses of FO supplements given before and during chemical peritonitis shift the balance of lipid mediators towards a proresolution, anti-inflammatory state without drastically altering the number or phenotype of local innate immune cell populations.
Collapse
Affiliation(s)
- Alexander C Chacon
- Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | | | | | | | - Shannon L Kelleher
- Department of Surgery, Hershey, Pennsylvania; Department of Cellular and Molecular Physiology, Hershey, Pennsylvania; Department of Pharmacology, Hershey, Pennsylvania
| | - David I Soybel
- Department of Surgery, Hershey, Pennsylvania; Department of Cellular and Molecular Physiology, Hershey, Pennsylvania.
| |
Collapse
|
8
|
Carlos D, Spiller F, Souto FO, Trevelin SC, Borges VF, de Freitas A, Alves-Filho JC, Silva JS, Ryffel B, Cunha FQ. Histamine h2 receptor signaling in the pathogenesis of sepsis: studies in a murine diabetes model. THE JOURNAL OF IMMUNOLOGY 2013; 191:1373-82. [PMID: 23817413 DOI: 10.4049/jimmunol.1202907] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Type 1 diabetes enhances susceptibility to infection and favors the sepsis development. In addition, diabetic mice produced higher levels of histamine in several tissues and in the blood after LPS stimulation than nondiabetic mice. In this study, we aimed to explore the role of mast cells (MCs) and histamine in neutrophil migration and, consequently, infection control in diabetic mice with mild sepsis (MS) induced by cecum ligation and puncture. We used female BALB/c, MC-sufficient (WB/B6), MC-deficient (W/W(v)), and NOD mice. Diabetic mice given MS displayed 100% mortality within 24 h, whereas all nondiabetic mice survived for at least 5 d. The mortality rate of diabetic mice was reduced to 57% after the depletion of MC granules with compound 48/80. Moreover, this pretreatment increased neutrophil migration to the focus of infection, which reduced systemic inflammatory response and bacteremia. The downregulation of CXCR2 and upregulation of G protein-coupled receptor kinase 2 in neutrophils was prevented by pretreatment of diabetic mice given MS with compound 48/80. In addition, blocking the histamine H2 receptor restored neutrophil migration, enhanced CXCR2 expression, decreased bacteremia, and improved sepsis survival in alloxan-induced diabetic and spontaneous NOD mice. Finally, diabetic W/W(v) mice had neutrophil migration to the peritoneal cavity, increased CXCR2 expression, and reduced bacteremia compared with diabetic WB/B6 mice. These results demonstrate that histamine released by MCs reduces diabetic host resistance to septic peritonitis in mice.
Collapse
Affiliation(s)
- Daniela Carlos
- Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, 14049-900 Ribeirão Preto, São Paulo, Brazil
| | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Nam YH, Min D, Kim HP, Song KJ, Kim KA, Lee YA, Kim SH, Shin MH. Leukotriene B4 receptor BLT-mediated phosphorylation of NF-κB and CREB is involved in IL-8 production in human mast cells induced by Trichomonas vaginalis-derived secretory products. Microbes Infect 2011; 13:1211-20. [DOI: 10.1016/j.micinf.2011.07.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Revised: 07/01/2011] [Accepted: 07/04/2011] [Indexed: 02/08/2023]
|
10
|
Spite M, Hellmann J, Tang Y, Mathis SP, Kosuri M, Bhatnagar A, Jala VR, Haribabu B. Deficiency of the leukotriene B4 receptor, BLT-1, protects against systemic insulin resistance in diet-induced obesity. THE JOURNAL OF IMMUNOLOGY 2011; 187:1942-9. [PMID: 21742977 DOI: 10.4049/jimmunol.1100196] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Chronic inflammation is an underlying factor linking obesity with insulin resistance. Diet-induced obesity promotes an increase in circulating levels of inflammatory monocytes and their infiltration into expanding adipose tissue. Nevertheless, the endogenous pathways that trigger and sustain chronic low-grade inflammation in obesity are incompletely understood. In this study, we report that a high-fat diet selectively increases the circulating levels of CD11b(+) monocytes in wild-type mice that express leukotriene B(4) receptor, BLT-1, and that this increase is abolished in BLT-1-null mice. The accumulation of classically activated (M1) adipose tissue macrophages (ATMs) and the expression of proinflammatory cytokines and chemokines (i.e., IL-6 and Ccl2) was largely blunted in adipose tissue of obese BLT-1(-/-) mice, whereas the ratio of alternatively activated (M2) ATMs to M1 ATMs was increased. Obese BLT-1(-/-) mice were protected from systemic glucose and insulin intolerance and this was associated with a decrease in inflammation in adipose tissue and liver and a decrease in hepatic triglyceride accumulation. Deletion of BLT-1 prevented high fat-induced loss of insulin signaling in liver and skeletal muscle. These observations elucidate a novel role of chemoattractant receptor, BLT-1, in promoting monocyte trafficking to adipose tissue and promoting chronic inflammation in obesity and could lead to the identification of new therapeutic targets for treating insulin resistance in obesity.
Collapse
Affiliation(s)
- Matthew Spite
- Division of Cardiovascular Medicine, Diabetes and Obesity Center, University of Louisville School of Medicine, Louisville, KY 40202, USA.
| | | | | | | | | | | | | | | |
Collapse
|
11
|
Peritoneal damage: the inflammatory response and clinical implications of the neuro-immuno-humoral axis. World J Surg 2010; 34:704-20. [PMID: 20049432 DOI: 10.1007/s00268-009-0382-y] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND The peritoneum is a bilayer serous membrane that lines the abdominal cavity. We present a review of peritoneal structure and physiology, with a focus on the peritoneal inflammatory response to surgical injury and its clinical implications. METHODS We conducted a nonsystematic clinical review. A search of the Ovid MEDLINE database from 1950 through January 2009 was performed using the following search terms: peritoneum, adhesions, cytokine, inflammation, and surgery. RESULTS The peritoneum is a metabolically active organ, responding to insult through a complex array of immunologic and inflammatory cascades. This response increases with the duration and extent of injury and is central to the concept of surgical stress, manifesting via a combination of systemic effects, and local neural pathways via the neuro-immuno-humoral axis. There may be a decreased systemic inflammatory response after minimally invasive surgery; however, it is unclear whether this is due to a reduced local peritoneal reaction. CONCLUSIONS Interventions that dampen the peritoneal response and/or block the neuro-immuno-humoral pathway should be further investigated as possible avenues of enhancing recovery after surgery, and reducing postoperative complications.
Collapse
|
12
|
Lefebvre JS, Marleau S, Milot V, Lévesque T, Picard S, Flamand N, Borgeat P. Toll-like receptor ligands induce polymorphonuclear leukocyte migration: key roles for leukotriene B4 and platelet-activating factor. FASEB J 2009; 24:637-47. [PMID: 19843712 DOI: 10.1096/fj.09-135624] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Activation of toll-like receptors (TLRs) and polymorphonuclear leukocyte (PMN) accumulation at infection sites are critical events of host defense. The involvement of leukotriene (LT) B(4) and platelet-activating factor (PAF) in TLR ligand-induced activation of inflammatory cell functions is essentially unknown. Using an in vitro model of human PMN migration through human endothelial cell monolayers, we demonstrate that prototypic ligands of TLR1/2, 2/6, 3, 4, 5, and 7/8 promote PMN migration, an effect markedly inhibited by 3 LTB(4) receptor antagonists (70-80% inhibition at 100 nM compared to vehicle-treated cells), 3 PAF receptor antagonists (20-50% inhibition at 10 nM), 3 LT biosynthesis inhibitors (75-85% inhibition at 100 nM), and 1 cytosolic phospholipase A(2)alpha (cPLA(2)alpha) inhibitor (90% inhibition at 1 microM). Accordingly, selected TLR ligands caused Ser-505-phosphorylation of cPLA(2)alpha and measurable LTB(4) and PAF biosynthesis in the transmigration assay. As negative controls, interleukin-8- and formyl-methionyl-leucyl-phenylalanine-elicited migration in vitro was not inhibited either by an LTB(4) receptor antagonist or by the cPLA(2)alpha inhibitor. Finally, LTB(4) and PAF receptor antagonists inhibited (up to approximately 65% at optimal doses) TLR ligand-induced PMN infiltration in the mouse air-pouch model. These studies unravel the critical involvement of de novo LTB(4) and PAF biosynthesis in PMN migration elicited by TLR ligands.
Collapse
Affiliation(s)
- Julie S Lefebvre
- Centre de Recherche en Rhumatologie et Immunologie, Centre Hospitalier Universitaire de Québec, 2705 Laurier Blvd., Rm. T1-49, Québec, QC, Canada, G1V 4G2
| | | | | | | | | | | | | |
Collapse
|
13
|
Anstead GM, Zhang Q, Melby PC. Malnutrition promotes prostaglandin over leukotriene production and dysregulates eicosanoid-cytokine crosstalk in activated resident macrophages. Prostaglandins Leukot Essent Fatty Acids 2009; 81:41-51. [PMID: 19541468 DOI: 10.1016/j.plefa.2009.04.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2008] [Revised: 12/17/2008] [Accepted: 04/28/2009] [Indexed: 02/02/2023]
Abstract
We previously described a murine model of malnutrition that mimicked features of moderate human malnutrition, and led to increased dissemination of Leishmania donovani. In this study, we investigated the effect of malnutrition on macrophage production of cytokines, prostaglandins (PGs), and leukotrienes (LTs). Using either LPS or calcium ionophore A23187 as a stimulus, macrophages from the malnourished mice produced a 3-fold higher PG/LT ((PGE(2)+6-keto-PGF(1alpha))/(LTB(4)+cysteinyl leukotrienes)) ratio than macrophages from well-nourished mice. LPS-stimulated macrophages from the malnourished mice produced decreased levels of TNF-alpha, GM-CSF, and IL-10, but similar levels of IL-6 and NO compared to well-nourished mice. A complex crosstalk between the eicosanoids and cytokines in the LPS-stimulated macrophages from the malnourished mice was evident by the following: (1) high levels of PG secretion despite low levels of TNF-alpha; (2) supplemental IL-10 modulated the excessive PG production; (3) GM-CSF rectified the PG/LT ratio, but did not correct the abnormal cytokine profile; and (4) inhibitors of cyclooxygenase decreased the PG/LT ratio, but did not affect TNF-alpha. Thus, in this model of malnutrition, there is a relative increase in anti-inflammatory PGs compared to pro-inflammatory LTs, which may contribute to immunodeficiency.
Collapse
Affiliation(s)
- G M Anstead
- Research Service, Audie L. Murphy Memorial Veterans Hospital, South Texas Veterans Health Care System, USA.
| | | | | |
Collapse
|
14
|
Blockade of CD137 signaling counteracts polymicrobial sepsis induced by cecal ligation and puncture. Infect Immun 2009; 77:3932-8. [PMID: 19564374 DOI: 10.1128/iai.00407-09] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sepsis, a leading cause of death worldwide, involves proinflammatory responses and inefficient bacterial clearance. Previously, we have shown that CD137 (4-1BB), a member of the tumor necrosis factor receptor superfamily, plays critical roles in eradicating infective Listeria monocytogenes, a gram-positive bacterium, and that stimulation of CD137 protects mice from sepsis-induced death. In this study, we unexpectedly found that CD137 activation aggravated polymicrobial sepsis due to mixed gram-positive and gram-negative bacterial infection induced by cecal ligation and puncture (CLP). CD137-deficient (CD137(-/-)) mice showed significantly lower mortality than CD137-sufficient (CD137(+/+)) mice in the CLP model. Administration of an agonistic anti-CD137 monoclonal antibody (MAb) to CD137(+/+) mice decreased their survival in this infection model, while administration of a blocking anti-CD137 ligand MAb (TKS-1) to such mice increased their survival. CD137(-/-) mice and TKS-1-treated CD137(+/+) mice had lower levels of chemokines/proinflammatory cytokines (monocyte chemoattractant protein 1, interleukin-6 [IL-6], tumor necrosis factor alpha, IL-12) and an anti-inflammatory cytokine (IL-10), exhibited improved bacterial clearance in the peritoneum, liver, and blood, and had greater numbers of infiltrated peritoneal neutrophils and macrophages in the CLP model than control mice. Our data suggest that CD137 activation aggravates polymicrobial sepsis induced by CLP.
Collapse
|
15
|
Uozumi N, Kita Y, Shimizu T. Modulation of lipid and protein mediators of inflammation by cytosolic phospholipase A2alpha during experimental sepsis. THE JOURNAL OF IMMUNOLOGY 2008; 181:3558-66. [PMID: 18714029 DOI: 10.4049/jimmunol.181.5.3558] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Cytosolic phospholipase A(2)alpha (cPLA(2)alpha) is one of the key enzymes in lipid mediator generation. It preferentially hydrolyzes arachidonoyl-phospholipid in response to cellular stimuli, liberating arachidonic acid, the shared precursor of PGs and leukotrienes. Mice with disruption of the cPLA(2)alpha gene exhibit a more than 80% decrease in the generation of these lipid mediators, leading to dramatic phenotypes in various models of inflammatory and allergic disease. In this study, we use the cecal ligation and puncture model of sepsis along with multiplex quantitation systems to explore interactions between eicosanoids and protein mediators. cPLA(2)alpha-deficient mice exhibited significantly less weight loss accompanied by decreased generation of PGs, leukotriene B(4), IL-6, and CCL2. Despite these differences, genetic ablation of cPLA(2)alpha did not provide any survival advantage. Unexpectedly, abundant production of 12-hydroxy-eicosatetraenoic acid, another arachidonic acid-derived lipid mediator, was found to be unaffected by disruption of the cPLA(2)alpha gene. Eicosanoid production preceded the production of cytokines. Eicosanoid modulation of IL-6 and CCL2 expression was suggested by scattergram analyses. These results provide in vivo evidence for the rapid generation of eicosanoids, regulatory role(s) for cPLA(2)alpha-derived lipid mediators on protein mediator production, and the existence of a robust cPLA(2)alpha-independent pathway(s) of eicosanoid generation.
Collapse
Affiliation(s)
- Naonori Uozumi
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Tokyo, Tokyo, Japan
| | | | | |
Collapse
|
16
|
LEUKOTRIENE B4/LEUKOTRIENE B4 RECEPTOR PATHWAY IS INVOLVED IN HEPATIC MICROCIRCULATORY DYSFUNCTION ELICITED BY ENDOTOXIN. Shock 2008; 30:87-91. [DOI: 10.1097/shk.0b013e31815d06a1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
17
|
van Till JWO, van Veen SQ, van Ruler O, Lamme B, Gouma DJ, Boermeester MA. The innate immune response to secondary peritonitis. Shock 2007; 28:504-17. [PMID: 17589378 DOI: 10.1097/shk.0b013e318063e6ca] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Secondary peritonitis continues to cause high morbidity and mortality despite improvements in medical and surgical therapy. This review combines data from published literature, focusing on molecular patterns of inflammation in pathophysiology and prognosis during peritonitis. Orchestration of the innate immune response is essential. To clear the microbial infection, activation and attraction of leukocytes are essential and beneficial, just like the expression of inflammatory cytokines. Exaggeration of these inflammatory systems leads to tissue damage and organ failure. Nonsurvivors have increased proinflammation, complement activation, coagulation, and chemotaxis. In these patients, anti-inflammatory systems are decreased in blood and lungs, whereas the abdominal compartment shows decreased neutrophil activation and decreased or stationary chemokine and cytokine levels. A later down-regulation of proinflammatory mediators with concomitant overexpression of anti-inflammatory mediators leads to immunoparalysis and failure to clear residual bacterial load, resulting in the occurrence of superimposed infections. Thus, in patients with adverse outcome, the inflammatory reaction is no longer contained within the abdomen, and the inflammatory response has shifted to other compartments. For the understanding of the host response to secondary peritonitis, it is essential to realize that the defense systems presumably are expressed differently and, in part, autonomously in different compartments.
Collapse
Affiliation(s)
- J W Olivier van Till
- Department of Surgery, Academic Medical Center, University of Amsterdam, The Netherlands
| | | | | | | | | | | |
Collapse
|
18
|
Shiratsuchi Y, Iyoda T, Tanimoto N, Kegai D, Nagata K, Kobayashi Y. Infiltrating neutrophils induce allospecific CTL in response to immunization with apoptotic cells via MCP-1 production. J Leukoc Biol 2006; 81:412-20. [PMID: 17095610 DOI: 10.1189/jlb.0606399] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Our previous studies demonstrated that i.p. injection of late apoptotic P388 cells caused phagocytosis by macrophages and transient infiltration of neutrophils into the peritoneal cavity. As neutrophils are known to function as effectors as well as regulators in the immune response, we examined the roles of infiltrating neutrophils in alloantigen-specific CTL induction after immunization with late apoptotic P388 cells. The CTL induction and infiltration of CD8(+) T cells into the peritoneal cavity were inhibited by depletion of neutrophils by anti-Gr-1 mAb or inhibition of neutrophil infiltration by anti-MIP-2 antibody, suggesting that neutrophils are involved in CD8(+) T cell infiltration into the peritoneal cavity. It is known that MIP-1alpha, MIP-1beta, and MCP-1 are capable of attracting CD8(+) T cells and that they are produced by neutrophils. These chemokines were detected in the peritoneal cavity, and among them, MCP-1 production was reduced remarkably by suppression of neutrophil infiltration. Moreover, infiltration of CD8(+) T cells into the peritoneal cavity as well as CTL activity was clearly reduced by administering anti-MCP-1 antibody i.p. Furthermore, the CTL induction and infiltration of CD8(+) T cells in neutrophil-depleted mice were restored significantly by administering recombinant murine MCP-1 into the peritoneal cavity. These results indicate that MCP-1 appears to link infiltration of neutrophils with CTL induction.
Collapse
Affiliation(s)
- Yoshiko Shiratsuchi
- Division of Molecular Medicine, Department of Biomolecular Science, Faculty of Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba, Japan
| | | | | | | | | | | |
Collapse
|
19
|
Abstract
A recent hypothesis postulates that sepsis moves through different phases, with periods of enhanced inflammation alternating with periods of immune suppression. In this study we determined the levels of inflammation present during early and late septic deaths to examine whether death was due to hyperinflammation or immunosuppression. The murine model of sepsis induced by cecal ligation and puncture (CLP) was used. Complete blood counts, plasma interleukin-6 (IL-6) levels, and body weights were determined. Mice that died within the first 4 days had increased plasma levels of IL-6, indicating that there was activation of the immune system. Cecal resection on day 4 after CLP resulted in decreased abscess size, lower circulating neutrophil counts, decreased anemia, and improved survival compared to the results for mice that received only antibiotic and fluid therapy. All of the mice that died in the chronic phase of infection (after day 4) had positive peritoneal cultures containing significantly more bacteria than the cultures for surviving mice. After day 4, none of the surviving mice exhibited increases in the plasma levels of IL-6. Dying mice exhibited mixed IL-6 responses; for 41% of the mice there was never an increase in the IL-6 levels in the chronic phase, while for other mice the levels of IL-6 transiently increased prior to death. Peritoneal macrophages were obtained in the late phase of sepsis from moribund and healthy mice and were stimulated ex vivo. The cells from the moribund mice produced significantly less IL-6 than the cells obtained from healthy mice produced. These results indicate that in mice that die in the early phase there is uniformly increased inflammation. However, during the chronic phase of sepsis, some mice die with evidence of immunosuppression (increased bacterial growth and low IL-6 levels), while other mice die with immunostimulation (high IL-6 levels and bacterial growth). Determining the inflammatory status of individual patients may help guide appropriate, targeted therapy.
Collapse
Affiliation(s)
- Hongyan Xiao
- Department of Pathology, University of Michigan, 2210 Medical Science I Building, 1301 Catherine Road, Ann Arbor, MI 48109-0602, USA
| | | | | |
Collapse
|
20
|
Banerjee A, Apte UM, Smith R, Ramaiah SK. Higher neutrophil infiltration mediated by osteopontin is a likely contributing factor to the increased susceptibility of females to alcoholic liver disease. J Pathol 2006; 208:473-85. [PMID: 16440289 DOI: 10.1002/path.1917] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Alcoholic liver disease (ALD) is a major public health problem in the United States and women are known to be more susceptible to ALD. However, the precise mechanism for increased susceptibility of females to ALD is not completely understood. The present study is based on the hypothesis that induction of osteopontin (OPN), a matricellular protein, is the likely contributing factor for higher neutrophil recruitment in females during alcoholic steatohepatitis (ASH). ASH was induced in male and female Sprague-Dawley rats by feeding them a Lieber-DeCarli diet containing ethanol (EtOH) for 6 weeks, followed by a single injection of lipopolysaccharide (LPS, 10 mg/kg, ip). Liver injury, measured by plasma transaminase elevations and confirmed by haematoxylin and eosin-stained liver sections, revealed approximately 25-fold higher liver injury in the female ASH model compared with the males. Although steatosis, necrosis, and neutrophil infiltration were evident in both male and female rats, hepatic neutrophilic necrotic foci were noted as early as 2 h after LPS injection in the EtOH-treated female rats. Hepatic neutrophil infiltration correlated with higher expression of cleaved (cOPN) and uncleaved OPN in the EtOH + LPS-treated female rats compared with the males. OPN secretion was localized predominantly in the biliary epithelium and females had significantly higher OPN mRNA than their male counterparts in the ASH model. The ability of OPN to attract neutrophils was further confirmed in vivo, in a peritonitis rat model, and by neutralizing OPN (nOPN) antibody experiments. Hepatic neutrophil infiltration was largely inhibited ( approximately 50%) by nOPN antibody. Flow cytometry experiments revealed OPN-mediated up-regulation of the CD11b neutrophil adhesion molecule. In conclusion, these data suggest that higher hepatic expression of OPN is the likely reason for higher and early hepatic neutrophil infiltration making females more susceptible to ALD during ASH.
Collapse
Affiliation(s)
- A Banerjee
- Department of Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, 77843-4467, USA
| | | | | | | |
Collapse
|