1
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Tuerxun K, Midtbö K, Särndahl E, Vorontsov E, Karlsson R, Persson A, Kruse R, Eklund D. Cytokine responses to LPS in reprogrammed monocytes are associated with the transcription factor PU.1. J Leukoc Biol 2022; 112:679-692. [PMID: 35285058 PMCID: PMC9790682 DOI: 10.1002/jlb.3a0421-216r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 01/21/2022] [Accepted: 01/30/2022] [Indexed: 12/30/2022] Open
Abstract
Myeloid-derived suppressor cells (MDSCs) are functionally immunosuppressive cells that arise and expand during extensive inflammatory conditions by increased hematopoietic output or reprogramming of immune cells. In sepsis, an increase of circulating MDSCs is associated with adverse outcomes, but unique traits that can be used to identify increased activity of MDSCs are lacking. By using endotoxin tolerance as a model of sepsis-induced monocytic MDSCs (M-MDSC-like cells), this study aims to identify the mediator and transcriptional regulator profile associated with M-MDSC activity. After analyzing 180 inflammation-associated proteins, a profile of differentially expressed cytokines was found in M-MDSC-like cells versus normal monocytes stimulated with LPS. These cytokines were associated with 5 candidate transcription factors, where particularly PU.1 showed differential expression on both transcriptional and protein levels in M-MDSC-like cells. Furthermore, inhibition of PU.1 led to increased production of CXCL5 and CCL8 in M-MDSC-like cells indicating its role in regulating the ability of M-MDSC-like cells to recruit other immune cells. Taken together, the study identifies a unique profile in the pattern of immune mediators defining M-MDSC activity upon LPS stimulation, which offers a functional link to their contribution to immunosuppression.
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Affiliation(s)
- Kedeye Tuerxun
- Faculty of Medicine and Health, School of Medical SciencesÖrebro UniversityÖrebroSweden,Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and HealthÖrebro UniversityÖrebroSweden
| | - Kristine Midtbö
- Faculty of Medicine and Health, School of Medical SciencesÖrebro UniversityÖrebroSweden,Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and HealthÖrebro UniversityÖrebroSweden
| | - Eva Särndahl
- Faculty of Medicine and Health, School of Medical SciencesÖrebro UniversityÖrebroSweden,Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and HealthÖrebro UniversityÖrebroSweden
| | - Egor Vorontsov
- Proteomics Core Facility, Sahlgrenska AcademyUniversity of GothenburgSweden
| | - Roger Karlsson
- Department of Infectious Diseases, Institute of BiomedicineSahlgrenska Academy of the University of GothenburgSweden,Department of Clinical MicrobiologySahlgrenska University Hospital, Region Västra GötalandSweden,Nanoxis Consulting ABGothenburgSweden
| | - Alexander Persson
- Faculty of Medicine and Health, School of Medical SciencesÖrebro UniversityÖrebroSweden,Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and HealthÖrebro UniversityÖrebroSweden
| | - Robert Kruse
- Faculty of Medicine and Health, School of Medical SciencesÖrebro UniversityÖrebroSweden,Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and HealthÖrebro UniversityÖrebroSweden,Department of Clinical Research Laboratory, Faculty of Medicine and HealthÖrebro UniversityÖrebroSweden
| | - Daniel Eklund
- Faculty of Medicine and Health, School of Medical SciencesÖrebro UniversityÖrebroSweden,Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and HealthÖrebro UniversityÖrebroSweden
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2
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Viola NT, Glassbrook JE, Kalluri JR, Hackett JB, Wicker MN, Sternberg J, Gibson HM. Evaluation of an ImmunoPET Tracer for IL-12 in a Preclinical Model of Inflammatory Immune Responses. Front Immunol 2022; 13:870110. [PMID: 35634303 PMCID: PMC9130849 DOI: 10.3389/fimmu.2022.870110] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Accepted: 04/13/2022] [Indexed: 11/18/2022] Open
Abstract
The immune cytokine interleukin-12 (IL-12) is involved in cancer initiation and progression, autoimmunity, as well as graft versus host disease. The ability to monitor IL-12 via imaging may provide insight into various immune processes, including levels of antitumor immunity, inflammation, and infection due to its functions in immune signaling. Here, we report the development and preclinical evaluation of an antibody-based IL-12-specific positron emission tomography (PET) tracer. To mimic localized infection and stimulate IL-12 production, BALB/c mice were administered lipopolysaccharide (LPS) intramuscularly. [89Zr]Zr-DFO-αIL12 tracer was given one hour post LPS administration and PET images were taken after 5, 24, 48, and 72 hours. We observed significantly higher uptake in LPS-treated mice as compared to controls. Biodistribution of the tracer was evaluated in a separate cohort of mice, where tracer uptake was elevated in muscle, spleen, lymph nodes, and intestines after LPS administration. To evaluate the utility of [89Zr]Zr-DFO-αIL12 as an indicator of antigen presenting cell activation after cancer immunotherapy, we compared PET imaging with and without intratumoral delivery of oncolytic adenovirus expressing granulocyte-macrophage colony-stimulating factor (Adv/GM-CSF), which we have shown promotes anti-tumor immunity. BALB/c mice were inoculated orthotopically with the mouse mammary carcinoma line TUBO. Once TUBO tumors reached a volume of ~50 mm3, mice were treated with either three intratumoral injections of 108 PFU Adv/GM-CSF or vehicle control, given every other day. Upon the last dose, [89Zr]Zr-DFO-αIL12 was injected intravenously and 72 hours later all mice were imaged via PET. Tumor-specific uptake of [89Zr]Zr-DFO-αIL12 was higher in Adv/GM-CSF treated mice versus controls. Tissues were harvested after imaging, and elevated levels of macrophages and CD8+ Tc cells were detected in Adv/GM-CSF treated tumors by immunohistochemistry. We validated that IL-12 expression was induced after Adv/GM-CSF by qRT-PCR. Importantly, expression of genes activated by IL-12 (IFNγ, TNFα, and IL-18) were unaffected after IL-12 imaging relative to mice receiving an IgG control tracer, suggesting the tracer antibody does not significantly disrupt signaling. Our results indicate that targeting soluble cytokines such as IL-12 by PET imaging with antibody tracers may serve as a noninvasive method to evaluate the function of the immune milieu in situ.
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Affiliation(s)
- Nerissa T Viola
- Department of Oncology, Karmanos Cancer Institute, Wayne State University, Detroit, MI, United States
| | - James E Glassbrook
- Department of Oncology, Karmanos Cancer Institute, Wayne State University, Detroit, MI, United States.,Department of Biochemistry Microbiology and Immunology, Wayne State University, Detroit, MI, United States
| | - Jhansi R Kalluri
- Department of Oncology, Karmanos Cancer Institute, Wayne State University, Detroit, MI, United States
| | - Justin B Hackett
- Cancer Biology Graduate Program, School of Medicine, Wayne State University, Detroit, MI, United States
| | - Madison N Wicker
- Department of Oncology, Karmanos Cancer Institute, Wayne State University, Detroit, MI, United States
| | - Joshua Sternberg
- Department of Oncology, Karmanos Cancer Institute, Wayne State University, Detroit, MI, United States
| | - Heather M Gibson
- Department of Oncology, Karmanos Cancer Institute, Wayne State University, Detroit, MI, United States
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3
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Perros AJ, Esguerra‐Lallen A, Rooks K, Chong F, Engkilde‐Pedersen S, Faddy HM, Hewlett E, Naidoo R, Tung J, Fraser JF, Tesar P, Ziegenfuss M, Smith S, O’Brien D, Flower RL, Dean MM. Coronary artery bypass grafting is associated with immunoparalysis of monocytes and dendritic cells. J Cell Mol Med 2020; 24:4791-4803. [PMID: 32180339 PMCID: PMC7176880 DOI: 10.1111/jcmm.15154] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 02/07/2020] [Accepted: 02/10/2020] [Indexed: 02/06/2023] Open
Abstract
Coronary artery bypass grafting (CABG) triggers a systemic inflammatory response that may contribute to adverse outcomes. Dendritic cells (DC) and monocytes are immunoregulatory cells potentially affected by CABG, contributing to an altered immune state. This study investigated changes in DC and monocyte responses in CABG patients at 5 time-points: admission, peri-operative, ICU, day 3 and day 5. Whole blood from 49 CABG patients was used in an ex vivo whole blood culture model to prospectively assess DC and monocyte responses. Lipopolysaccharide (LPS) was added in parallel to model responses to an infectious complication. Co-stimulatory and adhesion molecule expression and intracellular mediator production was measured by flow cytometry. CABG modulated monocyte and DC responses. In addition, DC and monocytes were immunoparalysed, evidenced by failure of co-stimulatory and adhesion molecules (eg HLA-DR), and intracellular mediators (eg IL-6) to respond to LPS stimulation. DC and monocyte modulation was associated with prolonged ICU length of stay and post-operative atrial fibrillation. DC and monocyte cytokine production did not recover by day 5 post-surgery. This study provides evidence that CABG modulates DC and monocyte responses. Using an ex vivo model to assess immune competency of CABG patients may help identify biomarkers to predict adverse outcomes.
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Affiliation(s)
- Alexis J. Perros
- Research and DevelopmentAustralian Red Cross LifebloodBrisbaneQLDAustralia
- School of MedicineUniversity of QueenslandBrisbaneQLDAustralia
- Critical Care Research Group (CCRG)The Prince Charles HospitalBrisbaneQLDAustralia
| | - Arlanna Esguerra‐Lallen
- Research and DevelopmentAustralian Red Cross LifebloodBrisbaneQLDAustralia
- Critical Care Research Group (CCRG)The Prince Charles HospitalBrisbaneQLDAustralia
- Adult Intensive Care ServicesThe Prince Charles HospitalBrisbaneQLDAustralia
| | - Kelly Rooks
- Research and DevelopmentAustralian Red Cross LifebloodBrisbaneQLDAustralia
| | - Fenny Chong
- Research and DevelopmentAustralian Red Cross LifebloodBrisbaneQLDAustralia
| | - Sanne Engkilde‐Pedersen
- Research and DevelopmentAustralian Red Cross LifebloodBrisbaneQLDAustralia
- Critical Care Research Group (CCRG)The Prince Charles HospitalBrisbaneQLDAustralia
- Adult Intensive Care ServicesThe Prince Charles HospitalBrisbaneQLDAustralia
| | - Helen M. Faddy
- Research and DevelopmentAustralian Red Cross LifebloodBrisbaneQLDAustralia
- School of MedicineUniversity of QueenslandBrisbaneQLDAustralia
- Faculty of HealthQueensland University of TechnologyBrisbaneQLDAustralia
- School of Health and Sport SciencesUniversity of the Sunshine CoastPetrieQLDAustralia
| | - Elise Hewlett
- Research and DevelopmentAustralian Red Cross LifebloodBrisbaneQLDAustralia
| | - Rishendran Naidoo
- Cardiothoracic Surgery ProgramThe Prince Charles HospitalBrisbaneQLDAustralia
| | - John‐Paul Tung
- Research and DevelopmentAustralian Red Cross LifebloodBrisbaneQLDAustralia
- School of MedicineUniversity of QueenslandBrisbaneQLDAustralia
- Critical Care Research Group (CCRG)The Prince Charles HospitalBrisbaneQLDAustralia
- Faculty of HealthQueensland University of TechnologyBrisbaneQLDAustralia
| | - John F. Fraser
- School of MedicineUniversity of QueenslandBrisbaneQLDAustralia
- Critical Care Research Group (CCRG)The Prince Charles HospitalBrisbaneQLDAustralia
- Adult Intensive Care ServicesThe Prince Charles HospitalBrisbaneQLDAustralia
| | - Peter Tesar
- Cardiothoracic Surgery ProgramThe Prince Charles HospitalBrisbaneQLDAustralia
| | - Marc Ziegenfuss
- Adult Intensive Care ServicesThe Prince Charles HospitalBrisbaneQLDAustralia
| | - Susan Smith
- Cardiothoracic Surgery ProgramThe Prince Charles HospitalBrisbaneQLDAustralia
| | - Donalee O’Brien
- Cardiothoracic Surgery ProgramThe Prince Charles HospitalBrisbaneQLDAustralia
| | - Robert L. Flower
- Research and DevelopmentAustralian Red Cross LifebloodBrisbaneQLDAustralia
- Faculty of HealthQueensland University of TechnologyBrisbaneQLDAustralia
| | - Melinda M. Dean
- Research and DevelopmentAustralian Red Cross LifebloodBrisbaneQLDAustralia
- Critical Care Research Group (CCRG)The Prince Charles HospitalBrisbaneQLDAustralia
- School of Health and Sport SciencesUniversity of the Sunshine CoastPetrieQLDAustralia
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4
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Katsafadou AI, Politis AP, Mavrogianni VS, Barbagianni MS, Vasileiou NGC, Fthenakis GC, Fragkou IA. Mammary Defences and Immunity against Mastitis in Sheep. Animals (Basel) 2019; 9:E726. [PMID: 31561433 PMCID: PMC6826578 DOI: 10.3390/ani9100726] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 09/22/2019] [Accepted: 09/24/2019] [Indexed: 12/26/2022] Open
Abstract
The objectives of this review paper are to present udder defences, including teat of the udder, mammary epithelial cells, leucocytes, immunoglobulins, complement system and chemical antibacterial agents, to describe cooperation and interactions between them and to elaborate on potentials regarding their significance in mammary immunisation strategies. The teat of the udder provides initial protection to the mammary gland. The mammary epithelial cells synthesise antibacterial proteins and the leucocytes produce various inflammation mediators (cytokines or chemokines), phagocytose bacteria and recognise antigenic structures. In the mammary gland, four immunoglobulins (IgG1, IgG2, IgM and IgA) have important roles against bacterial pathogens. The complement system is a collection of proteins, participating in the inflammatory process through various pathways. Other components contributing to humoral mammary defence include lactoferrin, lysozyme and the lactoperoxidase/myeloperoxidase systems, as well as oligosaccharides, gangliosides, reactive oxygen species, acute phase proteins (e.g., haptoglobin and serum amyloid A), ribonucleases and a wide range of antimicrobial peptides. Management practices, genetic variations and nutrition can influence mammary defences and should be taken into account in the formulation of prevention strategies against ovine mastitis.
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5
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Modeling the Bistable Dynamics of the Innate Immune System. Bull Math Biol 2018; 81:256-276. [PMID: 30387078 DOI: 10.1007/s11538-018-0527-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 10/22/2018] [Indexed: 10/28/2022]
Abstract
The size of primary challenge with lipopolysaccharide induces changes in the innate immune cells phenotype between pro-inflammatory and pro-tolerant states when facing a secondary lipopolysaccharide challenge. To determine the molecular mechanisms governing this differential response, we propose a mathematical model for the interaction between three proteins involved in the immune cell decision making: IRAK-1, PI3K, and RelB. The mutual inhibition of IRAK-1 and PI3K in the model leads to bistable dynamics. By using the levels of RelB as indicative of strength of the immune responses, we connect the size of different primary lipopolysaccharide doses to the differential phenotypical outcomes following a secondary challenge. We further predict under what circumstances the primary LPS dose does not influence the response to a secondary challenge. Our results can be used to guide treatments for patients with either autoimmune disease or compromised immune system.
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6
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Roque K, Shin KM, Jo JH, Lim GD, Song ES, Shin SJ, Gautam R, Lee JH, Kim YG, Cho AR, Kim CY, Kim HJ, Lee MS, Oh HG, Lee BC, Kim JH, Kim KH, Jeong HK, Kim HA, Heo Y. Association between endotoxin levels in dust from indoor swine housing environments and the immune responses of pigs. J Vet Sci 2018; 19:331-338. [PMID: 29366303 PMCID: PMC5974514 DOI: 10.4142/jvs.2018.19.3.331] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 01/08/2018] [Accepted: 01/23/2018] [Indexed: 11/24/2022] Open
Abstract
Indoor animal husbandry environments are inevitably contaminated with endotoxins. Endotoxin exposure is associated with various inflammatory illnesses in animals. This cross-sectional study evaluated the relationship between the degree of endotoxin exposure and the cellular and humoral immune profiles of fattening pigs. Blood samples were taken from the jugular vein of 47 pigs from ten pig farms in Korea. Whole blood cell counts and plasma immunoglobulin (Ig) classes were determined. Peripheral-blood mononuclear cells were stimulated in vitro with concanavalin A for 48 h, and cytokines released into culture supernatants were measured. The barns in which the pigs lived were assessed for endotoxin levels in the total and respirable dust by using the limulus amebocyte lysate kinetic QCL method. Low and high endotoxin exposures were defined as ≤ 30 and > 30 EU/m3, respectively. Compared to pigs with low endotoxin exposure (n = 19), highly exposed pigs (n = 28) had higher circulating neutrophil and lymphocyte (particularly B cells) counts, IgG and IgE levels, interferon-gamma (IFNγ) and interleukin (IL)-4 productions, and lower IgA levels and tumor necrosis factor-alpha (TNFα) production. The IL-4, IFNγ, and TNFα levels significantly correlated with endotoxin level and/or pig age. Constant exposure of pigs to high levels of airborne endotoxins can lead to aberrant immune profiles.
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Affiliation(s)
- Katharine Roque
- Department of Occupational Health, College of Bio-Medical Sciences, Daegu Catholic University, Gyeongsan 38430, Korea
| | - Kyung Min Shin
- Department of Occupational Health, College of Bio-Medical Sciences, Daegu Catholic University, Gyeongsan 38430, Korea
| | - Ji Hoon Jo
- Department of Occupational Health, College of Bio-Medical Sciences, Daegu Catholic University, Gyeongsan 38430, Korea
| | - Gyeong Dong Lim
- Department of Occupational Health, College of Bio-Medical Sciences, Daegu Catholic University, Gyeongsan 38430, Korea
| | - Eun Seob Song
- Department of Occupational Health, College of Bio-Medical Sciences, Daegu Catholic University, Gyeongsan 38430, Korea
| | - So Jung Shin
- Department of Occupational Health, College of Bio-Medical Sciences, Daegu Catholic University, Gyeongsan 38430, Korea
| | - Ravi Gautam
- Department of Occupational Health, College of Bio-Medical Sciences, Daegu Catholic University, Gyeongsan 38430, Korea
| | - Jae Hee Lee
- Department of Occupational Health, College of Bio-Medical Sciences, Daegu Catholic University, Gyeongsan 38430, Korea
| | - Yeon Gyeong Kim
- Department of Occupational Health, College of Bio-Medical Sciences, Daegu Catholic University, Gyeongsan 38430, Korea
| | - Ah Rang Cho
- Department of Occupational Health, College of Bio-Medical Sciences, Daegu Catholic University, Gyeongsan 38430, Korea
| | - Chang Yul Kim
- Department of Occupational Health, College of Bio-Medical Sciences, Daegu Catholic University, Gyeongsan 38430, Korea
| | - Hyun Ji Kim
- Department of Occupational Health, College of Bio-Medical Sciences, Daegu Catholic University, Gyeongsan 38430, Korea
| | - Myung Sook Lee
- Technology Services Division, National Institute of Animal Science, Wanju 55365, Korea
| | - Hyeong-Geu Oh
- Technology Services Division, National Institute of Animal Science, Wanju 55365, Korea
| | - Byung-Chul Lee
- Technology Services Division, National Institute of Animal Science, Wanju 55365, Korea
| | - Jung Hee Kim
- Dodram Pig Farmer's Cooperative, Veterinary Service Center, Daejeon 35352, Korea
| | - Kwang-Ho Kim
- Dodram Pig Farmer's Cooperative, Veterinary Service Center, Daejeon 35352, Korea
| | - Hyun Kyu Jeong
- Dodram Pig Farmer's Cooperative, Veterinary Service Center, Daejeon 35352, Korea
| | - Hyoung Ah Kim
- Department of Preventive Medicine, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
| | - Yong Heo
- Department of Occupational Health, College of Bio-Medical Sciences, Daegu Catholic University, Gyeongsan 38430, Korea
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7
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Sirtuin1 Targeting Reverses Innate and Adaptive Immune Tolerance in Septic Mice. J Immunol Res 2018; 2018:2402593. [PMID: 30069485 PMCID: PMC6057336 DOI: 10.1155/2018/2402593] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 05/29/2018] [Indexed: 01/08/2023] Open
Abstract
Resistance and tolerance to infection are two universal fitness and survival strategies used by inflammation and immunity in organisms and cells to guard homeostasis. During sepsis, however, both strategies fail, and animal and human victims often die from combined innate and adaptive immune suppression with persistent bacterial and viral infections. NAD+-sensing nuclear sirtuin1 (SIRT1) epigenetically guards immune and metabolic homeostasis during sepsis. Pharmacologically inhibiting SIRT1 deacetylase activity in septic mice reverses monocyte immune tolerance, clears infection, rebalances glycolysis and glucose oxidation, resolves organ dysfunction, and prevents most septic deaths. Whether SIRT1 inhibition during sepsis treatment concomitantly reverses innate and T cell antigen-specific immune tolerance is unknown. Here, we show that treating septic mice with a SIRT1 selective inhibitor concordantly reverses immune tolerance splenic dendritic and antigen-specific tolerance of splenic CD4+ and CD8+ T cells. SIRT1 inhibition also increases the ratio of IL12 p40+ and TNFα proinflammatory/immune to IL10 and TGFβ anti-inflammatory/immune cytokines and decreases the ratio of CD4+ TReg repressor to CD4+ activator T cells. These findings support the unifying concept that nuclear NAD+ sensor SIRT1 broadly coordinates innate and adaptive immune reprogramming during sepsis and is a druggable immunometabolic enhancement target.
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8
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Rackov G, Shokri R, De Mon MÁ, Martínez-A C, Balomenos D. The Role of IFN-β during the Course of Sepsis Progression and Its Therapeutic Potential. Front Immunol 2017; 8:493. [PMID: 28533774 PMCID: PMC5420561 DOI: 10.3389/fimmu.2017.00493] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 04/10/2017] [Indexed: 12/17/2022] Open
Abstract
Sepsis is a complex biphasic syndrome characterized by both pro- and anti-inflammatory immune states. Whereas early sepsis mortality is caused by an acute, deleterious pro-inflammatory response, the second sepsis phase is governed by acute immunosuppression, which predisposes patients to long-term risk for life-threatening secondary infections. Despite extensive basic research and clinical trials, there is to date no specific therapy for sepsis, and mortality rates are on the rise. Although IFN-β is one of the most-studied cytokines, its diverse effects are not fully understood. Depending on the disease or type of infection, it can have beneficial or detrimental effects. As IFN-β has been used successfully to treat diverse diseases, emphasis has been placed on understanding the role of IFN-β in sepsis. Analyses of mouse models of septic shock attribute a pro-inflammatory role to IFN-β in sepsis development. As anti-inflammatory treatments in humans with antibodies to TNF-α or IL1-β resulted disappointing, cytokine modulation approaches were discouraged and neutralization of IFN-β has not been pursued for sepsis treatment. In the case of patients with delayed sepsis and immunosuppression, there is a debate as to whether the use of specific cytokines would restore the deactivated immune response. Recent reports show an association of low IFN-β levels with the hyporesponsive state of monocytes from sepsis patients and after endotoxin tolerance induction. These data, discussed here, project a role for IFN-β in restoring monocyte function and reversing immunosuppression, and suggest IFN-β-based additive immunomodulatory therapy. The dichotomy in putative therapeutic approaches, involving reduction or an increase in IFN-β levels, mirrors the contrasting nature of the early hyperinflammatory state and the delayed immunosuppression phase.
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Affiliation(s)
- Gorjana Rackov
- Department of Immunology and Oncology, Universidad Autónoma de Madrid, Centro Nacional de Biotecnología - CSIC, Madrid, Spain.,IMDEA Nanoscience, Universidad Autónoma de Madrid, Madrid, Spain
| | - Rahman Shokri
- Department of Immunology and Oncology, Universidad Autónoma de Madrid, Centro Nacional de Biotecnología - CSIC, Madrid, Spain
| | - Melchor Álvarez De Mon
- Immune System Diseases-Rheumatology and Oncology Service, University Hospital Principe de Asturias, Alcalá de Henares, Spain
| | - Carlos Martínez-A
- Department of Immunology and Oncology, Universidad Autónoma de Madrid, Centro Nacional de Biotecnología - CSIC, Madrid, Spain
| | - Dimitrios Balomenos
- Department of Immunology and Oncology, Universidad Autónoma de Madrid, Centro Nacional de Biotecnología - CSIC, Madrid, Spain
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9
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Salazar F, Awuah D, Negm OH, Shakib F, Ghaemmaghami AM. The role of indoleamine 2,3-dioxygenase-aryl hydrocarbon receptor pathway in the TLR4-induced tolerogenic phenotype in human DCs. Sci Rep 2017; 7:43337. [PMID: 28256612 PMCID: PMC5335671 DOI: 10.1038/srep43337] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 01/25/2017] [Indexed: 12/27/2022] Open
Abstract
A controlled inflammatory response is required for protection against infection, but persistent inflammation causes tissue damage. Dendritic cells (DCs) have a unique capacity to promote both inflammatory and anti-inflammatory processes. One key mechanism involved in DC-mediated immunosuppression is the expression of tryptophan-metabolizing enzyme indoleamine 2,3-dioxygenase (IDO). IDO has been implicated in diverse processes in health and disease but its role in endotoxin tolerance in human DCs is still controversial. Here we investigated the role of IDO in shaping DCs phenotype and function under endotoxin tolerance conditions. Our data show that TLR4 ligation in LPS-primed DCs, induced higher levels of both IDO isoforms together with the transcription factor aryl-hydrocarbon receptor (AhR), compared to unprimed controls. Additionally, LPS conditioning induced an anti-inflammatory phenotype in DCs - with an increase in IL-10 and higher expression of programmed death ligand (PD-L)1 and PD-L2 - which were partially dependent on IDO. Furthermore, we demonstrated that the AhR-IDO pathway was responsible for the preferential activation of non-canonical NF-κB pathway in LPS-conditioned DCs. These data provide new insight into the mechanisms of the TLR4-induced tolerogenic phenotype in human DCs, which can help the better understanding of processes involved in induction and resolution of chronic inflammation and tolerance.
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MESH Headings
- B7-H1 Antigen/genetics
- B7-H1 Antigen/immunology
- Basic Helix-Loop-Helix Transcription Factors/genetics
- Basic Helix-Loop-Helix Transcription Factors/immunology
- Cell Adhesion Molecules/genetics
- Cell Adhesion Molecules/immunology
- Cell Differentiation/drug effects
- Dendritic Cells/cytology
- Dendritic Cells/drug effects
- Dendritic Cells/immunology
- Gene Expression Regulation
- Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology
- Humans
- Immune Tolerance
- Indoleamine-Pyrrole 2,3,-Dioxygenase/genetics
- Indoleamine-Pyrrole 2,3,-Dioxygenase/immunology
- Interleukin-10/genetics
- Interleukin-10/immunology
- Interleukin-4/pharmacology
- Lectins, C-Type/genetics
- Lectins, C-Type/immunology
- Lipopolysaccharides/pharmacology
- Monocytes/cytology
- Monocytes/drug effects
- Monocytes/immunology
- NF-kappa B/genetics
- NF-kappa B/immunology
- Primary Cell Culture
- Programmed Cell Death 1 Ligand 2 Protein/genetics
- Programmed Cell Death 1 Ligand 2 Protein/immunology
- Protein Serine-Threonine Kinases/genetics
- Protein Serine-Threonine Kinases/immunology
- Receptors, Aryl Hydrocarbon/genetics
- Receptors, Aryl Hydrocarbon/immunology
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/immunology
- Signal Transduction
- TNF Receptor-Associated Factor 3/genetics
- TNF Receptor-Associated Factor 3/immunology
- Toll-Like Receptor 4/genetics
- Toll-Like Receptor 4/immunology
- Transcription Factor RelB/genetics
- Transcription Factor RelB/immunology
- NF-kappaB-Inducing Kinase
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Affiliation(s)
- Fabián Salazar
- Division of Immunology, School of Life Sciences, Faculty of Medicine and Health Sciences, University of Nottingham, United Kingdom
| | - Dennis Awuah
- Division of Immunology, School of Life Sciences, Faculty of Medicine and Health Sciences, University of Nottingham, United Kingdom
| | - Ola H. Negm
- Division of Immunology, School of Life Sciences, Faculty of Medicine and Health Sciences, University of Nottingham, United Kingdom
- Medical Microbiology and Immunology Department, Mansoura University, Egypt
| | - Farouk Shakib
- Division of Immunology, School of Life Sciences, Faculty of Medicine and Health Sciences, University of Nottingham, United Kingdom
| | - Amir M. Ghaemmaghami
- Division of Immunology, School of Life Sciences, Faculty of Medicine and Health Sciences, University of Nottingham, United Kingdom
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10
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Medvedev AE, Sabroe I, Hasday JD, Vogel SN. Invited review: Tolerance to microbial TLR ligands: molecular mechanisms and relevance to disease. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/09680519060120030201] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Many host cell types, including endothelial and epithelial cells, neutrophils, monocytes, natural killer cells, dendritic cells and macrophages, initiate the first line of defense against infection by sensing conserved microbial structures through Toll-like receptors (TLRs). Recognition of microbial ligands by TLRs induces their oligomerization and triggers intracellular signaling pathways, leading to production of pro- and anti-inflammatory cytokines. Dysregulation of the fine molecular mechanisms that tightly control TLR signaling may lead to hyperactivation of host cells by microbial products and septic shock. A prior exposure to bacterial products such as lipopolysaccharide (LPS) may result in a transient state of refractoriness to subsequent challenge that has been referred to as `tolerance'. Tolerance has been postulated as a protective mechanism limiting excessive inflammation and preventing septic shock. However, tolerance may compromise the host's ability to counteract subsequent bacterial challenge since many septic patients exhibit an increased incidence of recurrent bacterial infection and suppressed monocyte responsiveness to LPS, closely resembling the tolerant phenotype. Thus, by studying mechanisms of microbial tolerance, we may gain insights into how normal regulatory mechanisms are dysregulated, leading ultimately to microbial hyporesponsivess and life-threatening disease. In this review, we present current theories of the molecular mechanisms that underlie induction and maintenance of `microbial tolerance', and discuss the possible relevance of tolerance to several infectious and non-infectious diseases.
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Affiliation(s)
- Andrei E. Medvedev
- Department of Microbiology and Immunology, University of Maryland, Baltimore (UMB), Baltimore, Maryland, USA,
| | - Ian Sabroe
- Academic Unit of Respiratory Medicine, Division of Genomic Medicine, University of Sheffield, Royal Hallamshire Hospital, Sheffield, UK
| | - Jeffrey D. Hasday
- Department of Medicine, University of Maryland, Baltimore (UMB), Baltimore, Maryland, USA
| | - Stefanie N. Vogel
- Department of Microbiology and Immunology, University of Maryland, Baltimore (UMB), Baltimore, Maryland, USA
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11
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Cross AS. Invited review: Endotoxin tolerance — current concepts in historical perspective. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/09680519020080020201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Alan S. Cross
- Division of Infectious Diseases, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA,
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12
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Abstract
The phenomenon of endotoxin tolerance has been widely investigated, but to date, the molecular mechanisms of endotoxin tolerance remain to be resolved clearly. The discovery of the Toll-like receptor (TLR) family as the major receptors for lipopolysaccharide (LPS) and other bacterial products has prompted a resurgence of interest in endotoxin tolerance mechanisms. Changes of cell surface molecules, signaling proteins, pro-inflammatory and anti -inflammatory cytokines and other mediators have been examined. During tolerance expression of LPS-binding protein (LBP), CD14, myeloid differentiation protein-2 (MD-2) and TLR2 are unchanged or up-regulated, whereas TLR4 is transiently suppressed or unchanged. Proximal post-receptor signaling proteins that are altered in tolerance include augmented degradation of interleukin-1 receptor-associated kinase (IRAK), and decreased TLR4-myeloid differentiation factor 88 (MyD88) and IRAK-MyD88 association. Tolerance has also been shown to be associated with decreased Gi protein content and activity, decreased protein kinase C (PKC) activity, reduction in mitogen-activated protein kinase (MAP kinase) activity, and reduced activator protein-1 (AP-1) and nuclear factor kappa B (NF-κB) induced gene transactivation. However, not all signaling proteins and pathways are suppressed in tolerance and induction of specific anti-inflammatory proteins and signaling pathways may serve important counter inflammatory functions. The latter include induction of IRAK-M and suppressor of cytokine-signaling-1 (SOCS-1), phosphoinositide-3-kinase (PI3K) signaling, and increased or maintained expression of inhibitor-κB (IκB) isoforms. Also at the nuclear level, increase in the NFκB subunit p50 homodimer expression and increased activation of peroxisome-proliferatoractivated receptors-γ (PPARγ) have been linked to tolerance phenotype. Although there are species and cellular variations in manifestation of the LPS tolerant phenotype, it is clear that the tolerance phenomena have evolved as a complex orchestrated counter regulatory response to inflammation.
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Affiliation(s)
- Hongkuan Fan
- Department of Physiology and Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA
| | - James A. Cook
- Department of Physiology and Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA,
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13
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Rackov G, Hernández-Jiménez E, Shokri R, Carmona-Rodríguez L, Mañes S, Álvarez-Mon M, López-Collazo E, Martínez-A C, Balomenos D. p21 mediates macrophage reprogramming through regulation of p50-p50 NF-κB and IFN-β. J Clin Invest 2016; 126:3089-103. [PMID: 27427981 DOI: 10.1172/jci83404] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 05/24/2016] [Indexed: 01/01/2023] Open
Abstract
M1 and M2 macrophage phenotypes, which mediate proinflammatory and antiinflammatory functions, respectively, represent the extremes of immunoregulatory plasticity in the macrophage population. This plasticity can also result in intermediate macrophage states that support a balance between these opposing functions. In sepsis, M1 macrophages can compensate for hyperinflammation by acquiring an M2-like immunosuppressed status that increases the risk of secondary infection and death. The M1 to M2 macrophage reprogramming that develops during LPS tolerance resembles the pathological antiinflammatory response to sepsis. Here, we determined that p21 regulates macrophage reprogramming by shifting the balance between active p65-p50 and inhibitory p50-p50 NF-κB pathways. p21 deficiency reduced the DNA-binding affinity of the p50-p50 homodimer in LPS-primed and -rechallenged macrophages, impairing their ability to attenuate IFN-β production and acquire an M2-like hyporesponsive status. High p21 levels in sepsis patients correlated with low IFN-β expression, and p21 knockdown in human monocytes corroborated its role in IFN-β regulation. The data demonstrate that p21 adjusts the equilibrium between p65-p50 and p50-p50 NF-κB pathways to mediate macrophage plasticity in LPS tolerance. Identifying p21-related pathways involved in monocyte reprogramming may lead to potential targets for sepsis treatment.
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14
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Zouikr I, Bartholomeusz MD, Hodgson DM. Early life programming of pain: focus on neuroimmune to endocrine communication. J Transl Med 2016; 14:123. [PMID: 27154463 PMCID: PMC4859995 DOI: 10.1186/s12967-016-0879-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Accepted: 04/27/2016] [Indexed: 01/21/2023] Open
Abstract
Chronic pain constitutes a challenge for the scientific community and a significant economic and social cost for modern societies. Given the failure of current drugs to effectively treat chronic pain, which are based on suppressing aberrant neuronal excitability, we propose in this review an integrated approach that views pain not solely originating from neuronal activation but also the result of a complex interaction between the nervous, immune, and endocrine systems. Pain assessment must also extend beyond measures of behavioural responses to noxious stimuli to a more developmentally informed assessment given the significant plasticity of the nociceptive system during the neonatal period. Finally integrating the concept of perinatal programming into the pain management field is a necessary step to develop and target interventions to reduce the suffering associated with chronic pain. We present clinical and animal findings from our laboratory (and others) demonstrating the importance of the microbial and relational environment in programming pain responsiveness later in life via action on hypothalamo-pituitary adrenal (HPA) axis activity, peripheral and central immune system, spinal and supraspinal mechanisms, and the autonomic nervous system.
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Affiliation(s)
- I Zouikr
- Laboratory of Neuroimmunology, School of Psychology, The University of Newcastle, Newcastle, NSW, Australia. .,Laboratory for Molecular Mechanisms of Thalamus Development, RIKEN BSI East Building 4F 409, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
| | - M D Bartholomeusz
- Laboratory of Neuroimmunology, School of Psychology, The University of Newcastle, Newcastle, NSW, Australia
| | - D M Hodgson
- Laboratory of Neuroimmunology, School of Psychology, The University of Newcastle, Newcastle, NSW, Australia
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15
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Ma X, Yan W, Zheng H, Du Q, Zhang L, Ban Y, Li N, Wei F. Regulation of IL-10 and IL-12 production and function in macrophages and dendritic cells. F1000Res 2015; 4. [PMID: 26918147 PMCID: PMC4754024 DOI: 10.12688/f1000research.7010.1] [Citation(s) in RCA: 151] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/16/2015] [Indexed: 12/20/2022] Open
Abstract
Interleukin-10 and Interleukin-12 are produced primarily by pathogen-activated antigen-presenting cells, particularly macrophages and dendritic cells. IL-10 and IL-12 play very important immunoregulatory roles in host defense and immune homeostasis. Being anti- and pro-inflammatory in nature, respectively, their functions are antagonistically opposing. A comprehensive and in-depth understanding of their immunological properties and signaling mechanisms will help develop better clinical intervention strategies in therapy for a wide range of human disorders. Here, we provide an update on some emerging concepts, controversies, unanswered questions, and opinions regarding the immune signaling of IL-10 and IL-12.
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Affiliation(s)
- Xiaojing Ma
- State Key Laboratory of Microbial Metabolism, Sheng Yushou Center of Cell Biology and Immunology, School of Life Science and Biotechnology, Shanghai Jiaotong University, Shanghai, USA; Department of Microbiology and Immunology, Weill Cornell Medical College, New York, NY, USA
| | - Wenjun Yan
- State Key Laboratory of Microbial Metabolism, Sheng Yushou Center of Cell Biology and Immunology, School of Life Science and Biotechnology, Shanghai Jiaotong University, Shanghai, USA
| | - Hua Zheng
- State Key Laboratory of Microbial Metabolism, Sheng Yushou Center of Cell Biology and Immunology, School of Life Science and Biotechnology, Shanghai Jiaotong University, Shanghai, USA
| | - Qinglin Du
- State Key Laboratory of Microbial Metabolism, Sheng Yushou Center of Cell Biology and Immunology, School of Life Science and Biotechnology, Shanghai Jiaotong University, Shanghai, USA
| | - Lixing Zhang
- State Key Laboratory of Microbial Metabolism, Sheng Yushou Center of Cell Biology and Immunology, School of Life Science and Biotechnology, Shanghai Jiaotong University, Shanghai, USA
| | - Yi Ban
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, NY, USA
| | - Na Li
- State Key Laboratory of Microbial Metabolism, Sheng Yushou Center of Cell Biology and Immunology, School of Life Science and Biotechnology, Shanghai Jiaotong University, Shanghai, USA
| | - Fang Wei
- State Key Laboratory of Microbial Metabolism, Sheng Yushou Center of Cell Biology and Immunology, School of Life Science and Biotechnology, Shanghai Jiaotong University, Shanghai, USA
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16
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Li CC, Munitic I, Mittelstadt PR, Castro E, Ashwell JD. Suppression of Dendritic Cell-Derived IL-12 by Endogenous Glucocorticoids Is Protective in LPS-Induced Sepsis. PLoS Biol 2015; 13:e1002269. [PMID: 26440998 PMCID: PMC4595142 DOI: 10.1371/journal.pbio.1002269] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 08/28/2015] [Indexed: 01/16/2023] Open
Abstract
Sepsis, an exaggerated systemic inflammatory response, remains a major medical challenge. Both hyperinflammation and immunosuppression are implicated as causes of morbidity and mortality. Dendritic cell (DC) loss has been observed in septic patients and in experimental sepsis models, but the role of DCs in sepsis, and the mechanisms and significance of DC loss, are poorly understood. Here, we report that mice with selective deletion of the glucocorticoid receptor (GR) in DCs (GRCD11c-cre) were highly susceptible to LPS-induced septic shock, evidenced by elevated inflammatory cytokine production, hypothermia, and mortality. Neutralizing anti-IL-12 antibodies prevented hypothermia and death, demonstrating that endogenous GC-mediated suppression of IL-12 is protective. In LPS-challenged GRCD11c-cre mice, CD8+ DCs were identified as the major source of prolonged IL-12 production, which correlated with elevations of NK cell-derived IFN-γ. In addition, the loss of GR in CD11c+ cells rescued LPS-induced loss of CD8+ DCs but not other DC subsets. Unlike wild-type animals, exposure of GRCD11c-cre mice to low-dose LPS did not induce CD8+ DC loss or tolerance to subsequent challenge with high dose, but neutralization of IL-12 restored the ability of low-dose LPS to tolerize. Therefore, endogenous glucocorticoids blunt LPS-induced inflammation and promote tolerance by suppressing DC IL-12 production. Lipopolysaccharide (LPS) from bacteria causes the increased production of endogenous glucocorticoids, protecting mice from sepsis and contributing to LPS tolerance by suppressing production of interleukin-12 (IL-12) by dendritic cells and causing the death of the primary producers of IL-12. Read the Synopsis. Sepsis refers to life-threatening systemic inflammation, often caused by infection with bacteria that produce lipopolysaccharide (LPS). Glucocorticoids, immunosuppressive hormones produced by the adrenals, have been used to treat sepsis for over 50 y, but little is known about the role of endogenous (naturally occurring) glucocorticoids in systemic inflammation. Macrophages have been considered the primary source of inflammatory mediators (cytokines) and a target for glucocorticoid-mediated suppression. The possible role of another immune cell population, dendritic cells, has not been explored in detail. We created a mouse model in which the glucocorticoid receptor is selectively deleted in dendritic cells (DCs). We found that the elevation of glucocorticoids that accompanies sepsis protects mice from LPS-induced septic shock by suppressing DC production of IL-12, a cytokine that causes the secretion of other inflammatory mediators. In addition, LPS-induced glucocorticoids caused the death of a subset of DCs that are the primary producers of IL-12. Glucocorticoids were also found to be important for the phenomenon of "LPS tolerance", in which inoculation with low-dose LPS makes mice resistant to rechallenge with a high dose. This unexpected role of DC-produced IL-12 and its suppression by endogenous glucocorticoids may account, at least in part, for the known association of adrenal insufficiency and prolonged sepsis.
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MESH Headings
- Animals
- Anti-Inflammatory Agents, Non-Steroidal/administration & dosage
- Anti-Inflammatory Agents, Non-Steroidal/therapeutic use
- Antibodies, Neutralizing/administration & dosage
- Antibodies, Neutralizing/therapeutic use
- CD11c Antigen/genetics
- CD11c Antigen/metabolism
- Cells, Cultured
- Crosses, Genetic
- Dendritic Cells/drug effects
- Dendritic Cells/immunology
- Dendritic Cells/metabolism
- Dendritic Cells/pathology
- Dose-Response Relationship, Drug
- Female
- Glucocorticoids/agonists
- Glucocorticoids/antagonists & inhibitors
- Glucocorticoids/blood
- Glucocorticoids/metabolism
- Immunity, Innate/drug effects
- Interleukin-12/antagonists & inhibitors
- Interleukin-12/blood
- Interleukin-12/metabolism
- Lipopolysaccharides/toxicity
- Male
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Receptors, Glucocorticoid/agonists
- Receptors, Glucocorticoid/antagonists & inhibitors
- Receptors, Glucocorticoid/genetics
- Receptors, Glucocorticoid/metabolism
- Shock, Septic/immunology
- Shock, Septic/metabolism
- Shock, Septic/pathology
- Shock, Septic/prevention & control
- Signal Transduction/drug effects
- Specific Pathogen-Free Organisms
- Spleen/drug effects
- Spleen/immunology
- Spleen/metabolism
- Spleen/pathology
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Affiliation(s)
- Caiyi C. Li
- Laboratory of Immune Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Ivana Munitic
- Laboratory of Immune Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Paul R. Mittelstadt
- Laboratory of Immune Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Ehydel Castro
- Laboratory of Immune Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Jonathan D. Ashwell
- Laboratory of Immune Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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17
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Murphy MB, Xiong Y, Pattabiraman G, Manavalan TT, Qiu F, Medvedev AE. Pellino-3 promotes endotoxin tolerance and acts as a negative regulator of TLR2 and TLR4 signaling. J Leukoc Biol 2015; 98:963-74. [PMID: 26310831 DOI: 10.1189/jlb.2vma0515-229rr] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 07/30/2015] [Indexed: 12/24/2022] Open
Abstract
Development of endotoxin tolerance in macrophages during sepsis reprograms Toll-like receptor 4 signaling to inhibit proinflammatory cytokines without suppressing anti-inflammatory and antimicrobial mediators and protects the host from excessive inflammation and tissue damage. However, endotoxin tolerance renders septic patients immunocompromised and unable to control secondary infections. Although previous studies have revealed the importance of several negative regulators of Toll-like receptor signaling in endotoxin tolerance, the role of Pellino proteins has not been addressed. The present report shows that the induction of endotoxin tolerance in vivo in mice and in vitro in human monocytes and THP-1 and MonoMac-6 macrophages increases the expression of Pellino-3. Overexpression of Pellino-3 in human embryonic kidney 293/Toll-like receptor 2 or 293/Toll-like receptor 4/myeloid differentiation factor-2 cells inhibited Toll-like receptor 2/4-mediated activation of nuclear factor-κB and induction of CXCL-8 mRNA, and Pellino-3 ablation increased these responses. Pellino-3-deficient THP-1 cells had elevated Toll-like receptor 2/4-driven tumor necrosis factor-α, interleukin-6 mRNA, and Toll-like receptor 4-driven CCL5 gene expression in response to Toll-like receptor agonists and heat-killed Escherichia coli and Staphylococcus aureus, cytokines controlled by the MyD88 and Toll-interleukin-1R domain-containing protein inducing interferon-β-mediated pathways, respectively. In addition, deficiency in Pellino-3 slightly increased phagocytosis of heat-killed bacteria. Transfected Pellino-3 inhibited nuclear factor-κB activation driven by overexpression of MyD88, TIR domain-containing adapter inducing interferon-β, interleukin-1R-associated kinase-1, and tumor necrosis factor receptor activator of nuclear factor-κB-binding kinase-1, TGF-β-activated kinase 1, and tumor necrosis factor receptor-associated factor-6, and inhibited interleukin-1R-associated kinase 1 modifications and tumor necrosis factor receptor activator of nuclear factor-κB-binding kinase 1 phosphorylation. Finally, Pellino-3 ablation in THP-1 decreased the extent of endotoxin tolerization. Thus, Pellino-3 is involved in endotoxin tolerance and functions as a negative regulator of Toll-like receptor 2/4 signaling.
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Affiliation(s)
- Michael B Murphy
- *Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut, USA; and Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Yanbao Xiong
- *Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut, USA; and Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Goutham Pattabiraman
- *Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut, USA; and Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Tissa T Manavalan
- *Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut, USA; and Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Fu Qiu
- *Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut, USA; and Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Andrei E Medvedev
- *Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut, USA; and Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
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18
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Molinaro R, Pecli C, Guilherme RF, Alves-Filho JC, Cunha FQ, Canetti C, Kunkel SL, Bozza MT, Benjamim CF. CCR4 Controls the Suppressive Effects of Regulatory T Cells on Early and Late Events during Severe Sepsis. PLoS One 2015. [PMID: 26197455 PMCID: PMC4511514 DOI: 10.1371/journal.pone.0133227] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Sepsis is a deadly disease characterized by an overwhelming release of inflammatory mediators and the activation of different types of cells. This altered state of cell activation, termed leukocyte reprogramming, contributes to patient outcome. However, the understanding of the process underlying sepsis and the role of regulatory T cells (Tregs) in sepsis remains to be elucidated. In this study, we investigated the role of CCR4, the CCL17/CCL22 chemokine receptor, in the innate and acquired immune responses during severe sepsis and the role of Tregs in effecting the outcome. In contrast with wild-type (WT) mice subjected to cecal ligation and puncture (CLP) sepsis, CCR4-deficient (CCR4-/-) septic mice presented an increased survival rate, significant neutrophil migration toward the infection site, a low bacterial count in the peritoneum, and reduced lung inflammation and serum cytokine levels. Thus, a better early host response may favor an adequate long-term response. Consequently, the CCR4-/- septic mice were not susceptible to secondary fungal infection, in contrast with the WT septic mice. Furthermore, Tregs cells from the CCR4-/- septic mice showed reduced suppressive effects on neutrophil migration (both in vivo and in vitro), lymphocyte proliferation and ROS production from activated neutrophils, in contrast with what was observed for Tregs from the WT septic mice. These data show that CCR4 is involved in immunosuppression after severe sepsis and suggest that CCR4+ Tregs negatively modulate the short and long-term immune responses.
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Affiliation(s)
- Raphael Molinaro
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Cyntia Pecli
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Rafael F. Guilherme
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - José Carlos Alves-Filho
- Departamento de Farmacologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Fernando Q. Cunha
- Departamento de Farmacologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Claudio Canetti
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Steven L. Kunkel
- Department of Pathology, University of Michigan, Ann Arbor, Michigan, 48109, United States of America
| | - Marcelo T. Bozza
- Departamento de Imunologia, Instituto de Microbiologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Claudia F. Benjamim
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
- * E-mail:
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19
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Murphy M, Xiong Y, Pattabiraman G, Qiu F, Medvedev AE. Pellino-1 Positively Regulates Toll-like Receptor (TLR) 2 and TLR4 Signaling and Is Suppressed upon Induction of Endotoxin Tolerance. J Biol Chem 2015; 290:19218-32. [PMID: 26082489 DOI: 10.1074/jbc.m115.640128] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Indexed: 11/06/2022] Open
Abstract
Endotoxin tolerance reprograms Toll-like receptor (TLR) 4-mediated macrophage responses by attenuating induction of proinflammatory cytokines while retaining expression of anti-inflammatory and antimicrobial mediators. We previously demonstrated deficient TLR4-induced activation of IL-1 receptor-associated kinase (IRAK) 4, IRAK1, and TANK-binding kinase (TBK) 1 as critical hallmarks of endotoxin tolerance, but mechanisms remain unclear. In this study, we examined the role of the E3 ubiquitin ligase Pellino-1 in endotoxin tolerance and TLR signaling. LPS stimulation increased Pellino-1 mRNA and protein expression in macrophages from mice injected with saline and in medium-pretreated human monocytes, THP-1, and MonoMac-6 cells, whereas endotoxin tolerization abrogated LPS inducibility of Pellino-1. Overexpression of Pellino-1 in 293/TLR2 and 293/TLR4/MD2 cells enhanced TLR2- and TLR4-induced nuclear factor κB (NF-κB) and expression of IL-8 mRNA, whereas Pellino-1 knockdown reduced these responses. Pellino-1 ablation in THP-1 cells impaired induction of myeloid differentiation primary response protein (MyD88), and Toll-IL-1R domain-containing adapter inducing IFN-β (TRIF)-dependent cytokine genes in response to TLR4 and TLR2 agonists and heat-killed Escherichia coli and Staphylococcus aureus, whereas only weakly affecting phagocytosis of heat-killed bacteria. Co-expressed Pellino-1 potentiated NF-κB activation driven by transfected MyD88, TRIF, IRAK1, TBK1, TGF-β-activated kinase (TAK) 1, and TNFR-associated factor 6, whereas not affecting p65-induced responses. Mechanistically, Pellino-1 increased LPS-driven K63-linked polyubiquitination of IRAK1, TBK1, TAK1, and phosphorylation of TBK1 and IFN regulatory factor 3. These results reveal a novel mechanism by which endotoxin tolerance re-programs TLR4 signaling via suppression of Pellino-1, a positive regulator of MyD88- and TRIF-dependent signaling that promotes K63-linked polyubiquitination of IRAK1, TBK1, and TAK1.
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Affiliation(s)
- Michael Murphy
- From the Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut 06030 and
| | - Yanbao Xiong
- the Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Goutham Pattabiraman
- From the Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut 06030 and
| | - Fu Qiu
- the Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Andrei E Medvedev
- From the Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut 06030 and
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20
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Emani R, Alam C, Pekkala S, Zafar S, Emani MR, Hänninen A. Peritoneal cavity is a route for gut-derived microbial signals to promote autoimmunity in non-obese diabetic mice. Scand J Immunol 2015; 81:102-9. [PMID: 25410403 DOI: 10.1111/sji.12253] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Accepted: 11/10/2014] [Indexed: 01/28/2023]
Abstract
Macrophages play a crucial role in innate immune reactions, and peritoneal macrophages (PMs) guard the sterility of this compartment mainly against microbial threat from the gut. Type 1 diabetes (T1D) is an autoimmune disease in which gut microbiota and gut immune system appear to contribute to disease pathogenesis. We have recently reported elevated free radical production and increased permeability of gut epithelium in non-obese diabetic (NOD) mice. Impaired barrier function could lead to bacterial leakage to the peritoneal cavity. To explore the consequences of impaired gut barrier function on extra-intestinal immune regulation, we characterized peritoneal lavage cells from young newly weaned NOD mice. We detected a rapid increase in the number of macrophages 1-2 weeks after weaning in NOD mice compared to C57BL/6 and BALB/c mice. Interestingly, this increase in macrophages was abrogated in NOD mice that were fed an antidiabetogenic diet (ProSobee), which improves gut barrier function. Macrophages in young (5-week-old) NOD mice displayed a poor TNF-α cytokine response to LPS stimulation and high expression of interleukin-1receptor-associated kinase-M (IRAK-M), indicating prior in vivo exposure to TLR-4 ligand(s). Furthermore, injection of LPS intraperitoneally increased T cell CD69 expression in pancreatic lymph node (PaLN), suggestive of T cell activation. Leakage of bacterial components such as endotoxins into the peritoneal cavity may contribute to auto-reactive T cell activation in the PaLN.
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Affiliation(s)
- R Emani
- Department of Medical Microbiology and Immunology, University of Turku, Turku, Finland
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21
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Fan X, Liu Z, Jin H, Yan J, Liang HP. Alterations of dendritic cells in sepsis: featured role in immunoparalysis. BIOMED RESEARCH INTERNATIONAL 2015; 2015:903720. [PMID: 25821827 PMCID: PMC4363672 DOI: 10.1155/2015/903720] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2014] [Revised: 05/25/2014] [Accepted: 07/28/2014] [Indexed: 12/12/2022]
Abstract
Sepsis, the leading cause of mortality in intensive care unit, is characterized by hyperinflammatory response in the early stage and followed by a period of immunosuppression. This immune disorder is believed to be the potent factor that is tightly associated with high mortality in sepsis. Dendritic cells (DCs) serve as professional antigen-presenting cells that play a vital role in immune response by activating T lymphocytes. During the progression of sepsis, DCs have been reported to take part in the aberrant immune response and be necessary for survival. Therefore, a better understanding of the DCs pathology will be undoubtedly beneficial for resolving the problems occurring in sepsis. This review discusses effects of sepsis on DCs number and function, including surface molecules expression, cytokines secretion, and T cell activation, and the underlying mechanism as well as some potential therapeutic strategies.
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Affiliation(s)
- Xia Fan
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, The Third Military Medical University, Chongqing 400042, China
| | - Zheng Liu
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, The Third Military Medical University, Chongqing 400042, China
| | - He Jin
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, The Third Military Medical University, Chongqing 400042, China
| | - Jun Yan
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, The Third Military Medical University, Chongqing 400042, China
| | - Hua-ping Liang
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, The Third Military Medical University, Chongqing 400042, China
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Dai J, El Gazzar M, Li GY, Moorman JP, Yao ZQ. Myeloid-derived suppressor cells: paradoxical roles in infection and immunity. J Innate Immun 2014; 7:116-26. [PMID: 25401944 DOI: 10.1159/000368233] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 09/09/2014] [Indexed: 12/31/2022] Open
Abstract
Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature suppressor cells that are generated due to aberrant myelopoiesis under pathological conditions. Although MDSCs have been recognized for more than 20 years under the guise of different monikers, these particular populations of myeloid cells gained more attention recently due to their immunosuppressive properties, which halt host immune responses to growing cancers or overwhelming infections. While MDSCs may contribute to immune homeostasis after infection or tissue injury by limiting excessive inflammatory processes, their expansion may be at the expense of pathogen elimination and thus may lead to disease persistence. Therefore, MDSCs may be either damaging or obliging to the host by attenuating, for example, antitumor or anti-infectious immune responses. In this review, we recapitulate the biological and immunological aspects of MDSCs, including their generation, distribution, trafficking and the factors involved in their activation, expansion, suppressive functions, and interplay between MDSCs and regulatory T cells, with a focus on the perspectives of infection and inflammation.
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Affiliation(s)
- Jun Dai
- Center for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, Tenn., USA
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López-Collazo E, del Fresno C. Pathophysiology of endotoxin tolerance: mechanisms and clinical consequences. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2013; 17:242. [PMID: 24229432 PMCID: PMC4059412 DOI: 10.1186/cc13110] [Citation(s) in RCA: 157] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Endotoxin tolerance was first described in a study that exposed animals to a sublethal dose of bacterial endotoxin. The animals subsequently survived a lethal injection of endotoxin. This refractory state is associated with the innate immune system and, in particular, with monocytes and macrophages, which act as the main participants. Several mechanisms are involved in the control of endotoxin tolerance; however, a full understanding of this phenomenon remains elusive. A number of recent reports indicate that clinical examples of endotoxin tolerance include not only sepsis but also diseases such as cystic fibrosis and acute coronary syndrome. In these pathologies, the risk of new infections correlates with a refractory state. This review integrates the molecular basis and clinical implications of endotoxin tolerance in various pathologies.
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Martin EM, Remke A, Pfeifer E, Polz J, Pietryga-Krieger A, Steffens-Weber D, Freudenberg MA, Mostböck S, Männel DN. TNFR2 maintains adequate IL-12 production by dendritic cells in inflammatory responses by regulating endogenous TNF levels. Innate Immun 2013; 20:712-20. [DOI: 10.1177/1753425913506949] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Sepsis-induced immune reactions are reduced in TNF receptor 2 (TNFR2)-deficient mice as previously shown. In order to elucidate the underlying mechanisms, the functional integrity of myeloid cells of TNFR2-deficient mice was analyzed and compared to wild type (WT) mice. The capacity of dendritic cells to produce IL-12 was strongly impaired in TNF-deficient mice, mirroring impaired production of IL-12 by WT dendritic cells in sepsis or after LPS or TNF pre-treatment. In addition, TNFR2-deficient mice were refractory to LPS pre-treatment and also to hyper-sensitization by inactivated Propionibacterium acnes, indicating habituation to inflammatory stimuli by the immune response when TNFR2 is lacking. Constitutive expression of TNF mRNA in kidney, liver, spleen, colon and lung tissue, and the presence of soluble TNFR2 in urine of healthy WT mice supported the conclusion that TNF is continuously present in naïve mice and controlled by soluble TNFR2. In TNFR2-deficient mice endogenous TNF levels cannot be balanced and the continuous exposure to enhanced TNF levels impairs dendritic cell function. In conclusion, TNF pre-exposure suppresses secondary inflammatory reactions of myeloid cells; therefore, continuous control of endogenous TNF by soluble TNFR2 seems to be essential for the maintenance of adequate sensitivity to inflammatory stimuli.
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Affiliation(s)
| | - Annika Remke
- Institute of Immunology, University of Regensburg, Regensburg, Germany
| | - Eva Pfeifer
- Institute of Immunology, University of Regensburg, Regensburg, Germany
| | - Johannes Polz
- Institute of Immunology, University of Regensburg, Regensburg, Germany
| | | | | | | | - Sven Mostböck
- Institute of Immunology, University of Regensburg, Regensburg, Germany
| | - Daniela N Männel
- Institute of Immunology, University of Regensburg, Regensburg, Germany
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NF-κB1 inhibits NOD2-induced cytokine secretion through ATF3-dependent mechanisms. Mol Cell Biol 2013; 33:4857-71. [PMID: 24100018 DOI: 10.1128/mcb.00797-13] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Regulation of microbially induced cytokine secretion is critical in intestinal immune homeostasis. NOD2, the Crohn's disease-associated bacterial peptidoglycan sensor, activates the NF-κB pathway. After chronic NOD2 stimulation in human macrophages, cytokine secretion is significantly attenuated, similar to the situation in the intestinal environment. We find that NF-κB1 (p105/p50) expression is upregulated with chronic NOD2 stimulation and is required for attenuation of cytokine secretion in vitro in human macrophages and in vivo in mice. Upon chronic NOD2 stimulation, regulation of both activating (H3K4Me2 and H4Ac) and inhibitory (H3K27Me3) histone modifications was observed within cytokine gene promoters; these outcomes were NF-κB1 dependent. In addition to enhanced binding to cytokine gene promoters with chronic NOD2 stimulation, NF-κB1 bound to the promoter of the transcriptional repressor, ATF3. ATF3 was then induced and bound to cytokine gene promoters; both features were impaired upon NF-κB1 knockdown. Restoring ATF3 expression under NF-κB1 knockdown conditions restored NOD2-mediated cytokine downregulation. Finally, NF-κB1 and ATF3 cooperate with other inhibitory pathways, including IRAKM and secreted mediators, to downregulate cytokine secretion after chronic NOD2 stimulation. Therefore, we identify NF-κB1 and ATF3 as critical mechanisms through which NOD2 downregulates cytokines and contributes to intestinal immune homeostasis.
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Lipopeptides rather than lipopolysaccharide favor the development of dendritic cell dysfunction similar to polymicrobial sepsis in mice. Inflamm Res 2013; 62:627-36. [DOI: 10.1007/s00011-013-0616-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Revised: 02/10/2013] [Accepted: 03/18/2013] [Indexed: 10/27/2022] Open
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Prince A. Innate Immune Responses in Ventilator-Associated Pneumonia. MUCOSAL IMMUNOLOGY OF ACUTE BACTERIAL PNEUMONIA 2013. [PMCID: PMC7121904 DOI: 10.1007/978-1-4614-5326-0_8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Ventilator-associated pneumonia (VAP) is a common complication of mechanical ventilation, resulting in substantial morbidity, mortality, and health care cost. Early upper airway colonization by pathogenic bacteria and microaspiration are the primary pathogenic events leading to VAP. Patients at risk for VAP have defects in structural/mechanical defenses of the respiratory tract. In addition, critical illness, including sepsis, trauma, and postoperative states, is associated with profound defects in both innate and acquired antibacterial immunity, influencing antimicrobial effector functions of both leukocytes and structural/parenchymal cells. Factors present within the lung microenvironment, including alveolar stretch, cyclical atelectasis, changes in oxygen tension, and respiratory tract microbiota, substantially impact antibacterial host responses. Mechanisms accounting for dysregulated immune homeostasis are incompletely understood, but likely involve: (1) alterations in the balance of pro- and anti-inflammatory cytokines; (2) changes in pathogen recognition receptor and G-protein coupled receptor expression and downstream signaling cascades; and (3) dysregulated cell death responses. Antibiotics and preventive strategies are the mainstay of therapy in patients with VAP. However, novel approaches are needed to reverse immunological reprogramming that occurs during critical illness and/or mechanical ventilation, and to identify patients who are most likely to benefit from immunomodulatory therapy.
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Pène F, Grimaldi D, Zuber B, Sauneuf B, Rousseau C, El Hachem C, Martin C, Belaïdouni N, Balloy V, Mira JP, Chiche JD. Toll-like receptor 2 deficiency increases resistance to Pseudomonas aeruginosa pneumonia in the setting of sepsis-induced immune dysfunction. J Infect Dis 2012; 206:932-42. [PMID: 22782952 DOI: 10.1093/infdis/jis438] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Sepsis is characterized by a dysregulated inflammatory response followed by immunosuppression that favors the development of secondary infections. Toll-like receptors (TLRs) are major regulators of the host's response to infections. How variability in TLR signaling may impact the development of sepsis-induced immune dysfunction has not been established. We sought to establish the role of TLR2, TLR4, and TLR5 in postseptic mice with Pseudomonas aeruginosa pneumonia. METHODS We used an experimental model of sublethal polymicrobial sepsis induced by cecal ligation and puncture (CLP). Wild-type, tlr2(-/-), tlr4(-/-), tlr5(-/-), tlr2 4(-/-) mice that underwent CLP were secondarily subjected to P. aeruginosa pulmonary infection. RESULTS Postseptic wild-type and tlr4(-/-) and tlr5(-/-) mice displayed high susceptibility to P. aeruginosa pneumonia. In contrast, TLR2-deficient mice, either tlr2(-/-)or tlr2 4(-/-), that underwent CLP were resistant to the secondary pulmonary infection. As compared to wild-type mice, tlr2(-/-) mice displayed improvement in bacterial clearance, decreased bacteremic dissemination, and attenuated lung damage. Furthermore, tlr2(-/-) mice exhibited a pulmonary proinflammatory cytokine balance, with increased production of tumor necrosis factor α and decreased release of interleukin 10. CONCLUSIONS In a model of secondary P. aeruginosa pneumonia in postseptic mice, TLR2 deficiency improves survival by promoting efficient bacterial clearance and restoring a proinflammatory cytokine balance in the lung.
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Adoptive transfer of CD34
+
cells during murine sepsis rebalances macrophage lipopolysaccharide responses. Immunol Cell Biol 2012; 90:925-34. [DOI: 10.1038/icb.2012.32] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Brudecki L, Ferguson DA, McCall CE, El Gazzar M. Myeloid-derived suppressor cells evolve during sepsis and can enhance or attenuate the systemic inflammatory response. Infect Immun 2012; 80:2026-34. [PMID: 22451518 PMCID: PMC3370575 DOI: 10.1128/iai.00239-12] [Citation(s) in RCA: 141] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 03/17/2012] [Indexed: 01/10/2023] Open
Abstract
Myeloid-derived suppressor cells (MDSCs) are a heterogeneous Gr1(+) CD11b(+) population of immature cells containing granulocytic and monocytic progenitors, which expand under nearly all inflammatory conditions and are potent repressors of T-cell responses. Studies of MDSCs during inflammatory responses, including sepsis, suggest they can protect or injure. Here, we investigated MDSCs during early and late sepsis. To do this, we used our published murine model of cecal ligation and puncture (CLP)-induced polymicrobial sepsis, which transitions from an early proinflammatory phase to a late anti-inflammatory and immunosuppressive phase. We confirmed that Gr1(+) CD11b(+) MDSCs gradually increase after CLP, reaching ∼88% of the bone marrow myeloid series in late sepsis. Adoptive transfer of early (day 3) MDSCs from septic mice into naive mice after CLP increased proinflammatory cytokine production, decreased peritoneal bacterial growth, and increased early mortality. Conversely, transfer of late (day 12) MDSCs from septic mice had the opposite effects. Early and late MDSCs studied ex vivo also differed in their inflammatory phenotypes. Early MDSCs expressed nitric oxide and proinflammatory cytokines, whereas late MDSCs expressed arginase activity and anti-inflammatory interleukin 10 (IL-10) and transforming growth factor β (TGF-β). Late MDSCs had more immature CD31(+) myeloid progenitors and, when treated ex vivo with granulocyte-macrophage colony-stimulating factor (GM-CSF), generated fewer macrophages and dendritic cells than early MDSCs. We conclude that as the sepsis inflammatory process progresses, the heterogeneous MDSCs shift to a more immature state and from being proinflammatory to anti-inflammatory.
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Affiliation(s)
| | - Donald A. Ferguson
- Microbiology, East Tennessee State University College of Medicine, Johnson City, Tennessee, USA
| | - Charles E. McCall
- Department of Internal Medicine, Section of Molecular Medicine, and Translational Science Institute, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
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31
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Zeng X, Wang T, Zhu C, Xing X, Ye Y, Lai X, Song B, Zeng Y. Topographical and biological evidence revealed FTY720-mediated anergy-polarization of mouse bone marrow-derived dendritic cells in vitro. PLoS One 2012; 7:e34830. [PMID: 22693544 PMCID: PMC3365054 DOI: 10.1371/journal.pone.0034830] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2011] [Accepted: 03/06/2012] [Indexed: 12/21/2022] Open
Abstract
Abnormal inflammations are central therapeutic targets in numerous infectious and autoimmune diseases. Dendritic cells (DCs) are involved in these inflammations, serving as both antigen presenters and proinflammatory cytokine providers. As an immuno-suppressor applied to the therapies of multiple sclerosis and allograft transplantation, fingolimod (FTY720) was shown to affect DC migration and its crosstalk with T cells. We posit FTY720 can induce an anergy-polarized phenotype switch on DCs in vitro, especially upon endotoxic activation. A lipopolysaccharide (LPS)-induced mouse bone marrow-derived dendritic cell (BMDC) activation model was employed to test FTY720-induced phenotypic changes on immature and mature DCs. Specifically, methods for morphology, nanostructure, cytokine production, phagocytosis, endocytosis and specific antigen presentation studies were used. FTY720 induced significant alterations of surface markers, as well as decline of shape indices, cell volume, surface roughness in LPS-activated mature BMDCs. These phenotypic, morphological and topographical changes were accompanied by FTY720-mediated down-regulation of proinflammatory cytokines, including IL-6, TNF-α, IL-12 and MCP-1. Together with suppressed nitric oxide (NO) production and CCR7 transcription in FTY720-treated BMDCs with or without LPS activation, an inhibitory mechanism of NO and cytokine reciprocal activation was suggested. This implication was supported by the impaired phagocytotic, endocytotic and specific antigen presentation abilities observed in the FTY720-treated BMDCs. In conclusion, we demonstrated FTY720 can induce anergy-polarization in both immature and LPS-activated mature BMDCs. A possible mechanism is FTY720-mediated reciprocal suppression on the intrinsic activation pathway and cytokine production with endpoint exhibitions on phagocytosis, endocytosis, antigen presentation as well as cellular morphology and topography.
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Affiliation(s)
- Xiangfeng Zeng
- Institute for Tissue Transplantation and Immunology, Jinan University, Guangzhou, China
| | - Tong Wang
- Institute for Tissue Transplantation and Immunology, Jinan University, Guangzhou, China
- Institute of Life and Health Engineering, Jinan University, Guangzhou, China
| | - Cairong Zhu
- Guangzhou Women and Children’s Medical Center, Guangzhou, Guangdong, China
| | - Xiaobo Xing
- Department of Chemistry, Jinan University, Guangzhou, China
- MOE Key Laboratory of Laser Life Science and Institute of Laser Life Science, South China Normal University, Guangzhou, China
| | - Yanxia Ye
- Institute for Tissue Transplantation and Immunology, Jinan University, Guangzhou, China
| | - Xinqiang Lai
- Institute for Tissue Transplantation and Immunology, Jinan University, Guangzhou, China
| | - Bing Song
- Institute for Tissue Transplantation and Immunology, Jinan University, Guangzhou, China
| | - Yaoying Zeng
- Institute for Tissue Transplantation and Immunology, Jinan University, Guangzhou, China
- * E-mail:
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Cole TS, Zhang M, Standiford TJ, Newstead M, Luther J, Zhang J, Chen CC, Kao JY. IRAK-M modulates expression of IL-10 and cell surface markers CD80 and MHC II after bacterial re-stimulation of tolerized dendritic cells. Immunol Lett 2012; 144:49-59. [PMID: 22472665 DOI: 10.1016/j.imlet.2012.03.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 03/04/2012] [Accepted: 03/12/2012] [Indexed: 01/22/2023]
Abstract
BACKGROUND As essential components of the innate immune system, dendritic cells (DCs) can interact directly with pathogens as well as participate in the adaptive immune response. In cells closely related to DCs such as macrophages and monocytes, prior exposure to minute amounts of endotoxin can lead to a refractory period where subsequent exposure to higher doses fails to induce an inflammatory response; little research has investigated this effect on DCs. This study tested if murine bone marrow-derived dendritic cells (BM-DCs) respond to endotoxin- and bacterial sonicate-induced tolerance by decreased inflammatory and increased anti-inflammatory response, and the role of IRAK-M, an intracellular negative regulator of TLR signaling, in this tolerance. RESULTS Tolerized BM-DCs exhibited a significant drop in TNF-α and IL-12p70 production and increased IL-10 expression compared to untolerized cells. BM-DCs also showed the ability to develop heterotolerance, in which the LPS exposure alone was able to induce tolerance to Helicobacter pylori sonicate and TLR2 agonist Pam3Cys. Furthermore, the expression of IRAK-M was increased after restimulation of tolerized BM-DCs as determined qPCR and Western blot. IRAK-M exhibited a suppressive effect on surface expression of major histocompatibilty complex class II (MHC II) and CD80 in LPS-tolerized BM-DCs. IL-10 expression in bacterial sonicate-tolerized IRAK-M-/- BM-DCs was altered as compared to wild type BM-DCs, with tolerance-induced expression of IL-10 mitigated in tolerized IRAK-M-/- BM-DCs. CONCLUSION Along with endotoxin, bacterial sonicate is able to induce refractory tolerance in BM-DCs, and IRAK-M plays a role in modulating cell surface expression of MHC class II and CD80 and release of IL-10 during this tolerance.
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Affiliation(s)
- Tyler S Cole
- Division of Gastroenterology, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109, United States
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Xiong Y, Medvedev AE. Induction of endotoxin tolerance in vivo inhibits activation of IRAK4 and increases negative regulators IRAK-M, SHIP-1, and A20. J Leukoc Biol 2011; 90:1141-8. [PMID: 21934070 DOI: 10.1189/jlb.0611273] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
TLRs mediate host defense against microbial pathogens by eliciting production of inflammatory mediators and activating expression of MHC, adhesion, and costimulatory molecules. Endotoxin tolerance limits excessive TLR-driven inflammation during sepsis and reprograms macrophage responses to LPS, decreasing expression of proinflammatory cytokines without inhibiting anti-inflammatory and antimicrobial mediators. Molecular mechanisms of reprogramming of TLR4 signaling upon in vivo induction of endotoxin tolerance are incompletely understood. We used an in vivo model of endotoxin tolerance, whereby C57BL/6 mice were i.p.-inoculated with LPS or PBS, followed by in vitro challenge of peritoneal or splenic macrophages with LPS to examine activation of IRAK4 and expression of negative regulatory molecules. Administration of LPS in vivo-induced endotoxin tolerance in peritoneal and splenic macrophages, as evidenced by decreased degradation of IκBα, suppressed phosphorylation of p38 and reduced expression of TNF-α, IL-6, and KC mRNA upon in vitro LPS challenge. Macrophages from control and endotoxin-tolerant mice exhibited comparable TLR4 mRNA levels and similar expression of IL-1RA and IL-10 genes. Endotoxin tolerization in vivo blocked TLR4-driven IRAK4 phosphorylation and activation in macrophages, while increasing expression of IRAK-M, SHIP-1, A20 mRNA, and A20 protein. Thus, induction of endotoxin tolerance in vivo inhibits expression of proinflammatory mediators via impaired activation of IRAK4, p38, and NF-κB and increases expression of negative regulators of TLR4 pathways.
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Affiliation(s)
- Yanbao Xiong
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
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Riccardi F, Della Porta MG, Rovati B, Casazza A, Radolovich D, De Amici M, Danova M, Langer M. Flow cytometric analysis of peripheral blood dendritic cells in patients with severe sepsis. CYTOMETRY PART B-CLINICAL CYTOMETRY 2011; 80:14-21. [PMID: 20687203 DOI: 10.1002/cyto.b.20540] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Dendritic cells (DC) play a key role in cell-mediated immunity. We aimed to analyse the number and function of peripheral blood (PB) myeloid and plasmacytoid DC (mDC/pDC) in patients with severe sepsis. METHODS Twenty-six septic patients, 20 surgical patients (abdominal aortic aneurysm) and 20 healthy controls were enrolled in this prospective study. RESULTS At day 1 (enrollment in the study), septic patients showed in comparison with healthy controls, decreased mDC (P < 0.001) and increased pDC (P = 0.03), resulting in a reduction of the mDC/pDC ratio (P < 0.001). Surgery induced a decrease in both mDCs and pDCs level, without modification of mDC/pDC ratio. Septic patients included 15 survivors and 11 nonsurvivors. At day 1 no significant difference was found in mDC between the two groups, while pDCs were significantly higher in nonsurvivors (P = 0.03). At the outcome, mDC were selectively increased with respect to day 1 in survivors (P = 0.001), while no significant differences were observed as far as pDC count is concerned in both groups. Sorted DC from septic patients showed in comparison with healthy controls, reduced levels of HLA DR (P < 0.001), CD11c (P < 0.001), CD83 (P = 0.006) and of costimulatory molecule CD86 (P = 0.003); an up-regulation of chemokine receptor CXCR4 (P = 0.031) and increased apoptosis (P < 0.001). CONCLUSIONS Sepsis has a profound effect on PB DC compartment. These alterations appear to be sepsis-specific. Increased apoptosis and alteration of migration and trafficking mechanism may be involved in DC compartment modification. DC alterations could contribute to sepsis-mediated immunoparalysis.
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Affiliation(s)
- Francesca Riccardi
- Servizio Anestesia e Rianimazione II, IRCCS Policlinico, S. Matteo and University of Pavia, Pavia, Italy.
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Auletta JJ, Alabran JL, Kim BG, Meyer CJ, Letterio JJ. The synthetic triterpenoid, CDDO-Me, modulates the proinflammatory response to in vivo lipopolysaccharide challenge. J Interferon Cytokine Res 2011; 30:497-508. [PMID: 20626291 DOI: 10.1089/jir.2009.0100] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The synthetic triterpenoid, CDDO-Me, has potent antiproliferative and antioxidant properties. However, its immunomodulatory effects in the context of LPS challenge are incompletely defined. Pretreatment with oral CDDO-Me significantly improved survival following lethal-dose LPS challenge in mice. To define this protection further, we measured effects of CDDO-Me pretreatment on splenocyte populations and cytokine production following LPS challenge, using low-level LPS pretreatment as an in vivo control for reducing cytokine production. Despite similar decreases in levels of LPS-inducible, circulating proinflammatory cytokines (IL-12p70, IFN-gamma, IL-6, IL-17, and IL-23) and increases in heme oxygenase 1 (HO-1) protein expression, low-dose LPS and CDDO-Me pretreatments markedly differed in their overall response profiles. Splenocytes from LPS-pretreated mice contained reduced numbers of dendritic cells, increased percentages of Th17 and T-regulatory cells, lower levels of TLR-inducible IL-6, and higher levels of TLR-inducible IL-10. In contrast, CDDO-Me protection against LPS challenge had no impact on absolute numbers or distribution of splenocyte subsets, despite attenuating in vivo induction of proinflammatory cytokines in an IL-10-independent manner. Together, these results suggest that CDDO-Me pretreatment uniquely confers protection against LPS challenge by modulating the in vivo immune response to LPS. Thus, CDDO-Me potentially represents a novel oral agent for use in LPS-mediated inflammatory diseases.
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Affiliation(s)
- Jeffery J Auletta
- Department of Pediatrics, Case Western Reserve University, Cleveland, Ohio, USA.
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Lenz AM, Qadan M, Gardner SA, Cheadle WG. Impact of microbial tolerance in persistent secondary Klebsiella pneumoniae peritonitis. Cytokine 2011; 53:84-93. [DOI: 10.1016/j.cyto.2010.08.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Revised: 06/25/2010] [Accepted: 08/31/2010] [Indexed: 11/29/2022]
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Sirgo G, Claramonte R, Chánovas M, Esteban F, Forcadell I, Luna J, Masdeu G, Ramón Vázquez J, Artigas A. [Dendritic cells in sepsis: an approach to post-infectious immunosuppression]. Med Intensiva 2010; 34:559-66. [PMID: 20034705 DOI: 10.1016/j.medin.2009.11.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2009] [Revised: 10/16/2009] [Accepted: 11/08/2009] [Indexed: 12/24/2022]
Abstract
Dendritic cells (DCs) play a decisive role in the immune system, especially in the initial events that determine coordination between the innate and adaptive response. Moreover, they are antigen-presenting cells which, through contact with T cells, determine the type of immune responses towards inflammatory or anti-inflammatory. Currently, the hypothesis that attributes importance to the development of a post-infectious immunosuppression in the prognosis of the septic patient is growing stronger. It has been possible to verify the role played by these cells in this type of immunosuppression by the significant decrease in the number of DCs and by the dysfunctions in the functional capacity that include, on the one hand, the abnormal cytokine production and, on the other hand, the alterations in communication between the DCs and T cells that constitute an essential immunological fact. Further research into the knowledge regarding the DCs, in the context of severe infection, may help to consolidate some encouraging data that indicate these cells as: 1) an effective tool for monitoring the acute infection, 2) a discriminatory variable that may help determine the risk of nosocomial infection and 3) in a longer term, a treatment target that would restore the immunological abnormalities that occur in sepsis.
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Affiliation(s)
- G Sirgo
- UMI, Hospital Verge de la Cinta, Tortosa, Tarragona, España.
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Yasuda Y, Matsumura Y, Kasahara K, Ouji N, Sugiura S, Mikasa K, Kita E. Microbial exposure early in life regulates airway inflammation in mice after infection with Streptococcus pneumoniae with enhancement of local resistance. Am J Physiol Lung Cell Mol Physiol 2010; 298:L67-78. [DOI: 10.1152/ajplung.00193.2009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The immunological explanation for the “hygiene hypothesis” has been proposed to be induction of T helper 1 (Th1) responses by microbial products. However, the protective results of hygiene hypothesis-linked microbial exposures are currently shown to be unlikely to result from a Th1-skewed response. Until now, effect of microbial exposure early in life on airway innate resistance remained unclear. We examined the role of early life exposure to microbes in airway innate resistance to a respiratory pathogen. Specific pathogen-free weanling mice were nasally exposed to the mixture of microbial extracts or PBS (control) every other day for 28 days and intratracheally infected with Streptococcus pneumoniae 10 days after the last exposure. Exposure to microbial extracts facilitated colonization of aerobic gram-positive bacteria, anaerobic microorganisms, and Lactobacillus in the airway, compared with control exposure. In pneumococcal pneumonia, the exposure prolonged mouse survival days by suppressing bacterial growth and by retarding pneumococcal blood invasion, despite significantly low levels of leukocyte recruitment in the lung. Enhancement of airway resistance was associated with a significant decrease in production of leukocyte chemokine (KC) and TNFα, and suppression of matrix metalloproteinase (MMP-9) expression/activation with enhancement of tissue inhibitor of MMP (TIMP-3) activation. The exposure increased production of IFN-γ, IL-4, and monocyte chemoattractant-1 following infection. Furthermore, expression of Toll-like receptor 2, 4, and 9 was promoted by the exposure but no longer upregulated upon pneumococcal infection. Thus, we suggest that hygiene hypothesis is more important in regulating the PMN-dominant inflammatory response than in inducing a Th1-dominant response.
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Affiliation(s)
| | | | | | | | | | - Keiichi Mikasa
- Center for Infectious Diseases, Nara Medical University, School of Medicine, Kashihara, Nara, Japan
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Day J, Rubin JE, Chow CC. Competition Between Transients in the Rate of Approach to a Fixed Point. SIAM JOURNAL ON APPLIED DYNAMICAL SYSTEMS 2009; 8:1523-1563. [PMID: 20011076 PMCID: PMC2790829 DOI: 10.1137/080718929] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The goal of this paper is to provide and apply tools for analyzing a specific aspect of transient dynamics not covered by previous theory. The question we address is whether one component of a perturbed solution to a system of differential equations can overtake the corresponding component of a reference solution as both converge to a stable node at the origin, given that the perturbed solution was initially farther away and that both solutions are nonnegative for all time. We call this phenomenon tolerance, for its relation to a biological effect. We show using geometric arguments that tolerance will exist in generic linear systems with a complete set of eigenvectors and in excitable nonlinear systems. We also define a notion of inhibition that may constrain the regions in phase space where the possibility of tolerance arises in general systems. However, these general existence theorems do not not yield an assessment of tolerance for specific initial conditions. To address that issue, we develop some analytical tools for determining if particular perturbed and reference solution initial conditions will exhibit tolerance.
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Affiliation(s)
- Judy Day
- Mathematical Biosciences Institute, The Ohio State University, 1735 Neil Ave, Jennings Hall, Columbus, OH 43210
| | - Jonathan E. Rubin
- Department of Mathematics, University of Pittsburgh, 301 Thackeray Hall, Pittsburgh, PA 15260
| | - Carson C. Chow
- Laboratory of Biological Modeling, NIDDK, National Institutes of Health, Building 12A, Room 4007, 12 South Drive MSC 5621, Bethesda, MD 20892
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Toll-like receptors 2 and 4 contribute to sepsis-induced depletion of spleen dendritic cells. Infect Immun 2009; 77:5651-8. [PMID: 19805530 DOI: 10.1128/iai.00238-09] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Depletion of dendritic cells (DC) in secondary lymphoid organs is a hallmark of sepsis-induced immune dysfunction. In this setting, we investigated if Toll-like receptor (TLR)-dependent signaling might modulate the maturation process and the survival of DC. Using a model of sublethal polymicrobial sepsis induced by cecal ligation and puncture, we investigated the quantitative and functional features of spleen DC in wild-type, TLR2(-/-), TLR4(-/-), and TLR2(-/-) TLR4(-/-) mice. By 24 h, a decrease in the relative percentage of CD11c(high) spleen DC occurred in wild-type mice but was prevented in TLR2(-/-), TLR4(-/-), and TLR2(-/-) TLR4(-/-) mice. In wild-type mice, sepsis dramatically affected both CD11c(+) CD8alpha(+) and CD11c(+) CD8alpha(-) subsets. In all three types of knockout mice studied, the CD11c(+) CD8alpha(+) subset followed a depletion pattern similar to that for wild-type mice. In contrast, the loss of CD11c(+) CD8alpha(-) cells was attenuated in TLR2(-/-) and TLR4(-/-) mice and completely prevented in TLR2(-/-) TLR4(-/-) mice. Accordingly, apoptosis of spleen DC was increased in septic wild-type mice and inhibited in knockout mice. In addition we characterized the functional features of spleen DC obtained from septic mice. As shown by increased expression of major histocompatibility complex class II and CD86, polymicrobial sepsis induced maturation of DC, with subsequent increased capacity to prime T lymphocytes, similarly in wild-type and knockout mice. In response to CpG DNA stimulation, production of interleukin-12 was equally impaired in DC obtained from wild-type and knockout septic mice. In conclusion, although dispensable for the DC maturation process, TLR2 and TLR4 are involved in the mechanisms leading to depletion of spleen DC following polymicrobial sepsis.
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Biswas SK, Lopez-Collazo E. Endotoxin tolerance: new mechanisms, molecules and clinical significance. Trends Immunol 2009; 30:475-87. [PMID: 19781994 DOI: 10.1016/j.it.2009.07.009] [Citation(s) in RCA: 963] [Impact Index Per Article: 64.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2009] [Revised: 07/14/2009] [Accepted: 07/15/2009] [Indexed: 02/06/2023]
Abstract
Prior exposure of innate immune cells like monocytes/macrophages to minute amounts of endotoxin cause them to become refractory to subsequent endotoxin challenge, a phenomenon called "endotoxin tolerance". Clinically, this state is associated with monocytes/macrophages in sepsis patients where they contribute to "immunosuppression" and mortality. The molecular mechanisms underlying endotoxin tolerance remain elusive. The recent appreciation of inflammation as a self-regulating process, the relative contribution of MyD88 versus TRIF signaling pathways in inducing activation or tolerance, plasticity of NF-kappaB function and the role of chromatin modification and microRNAs in LPS-induced gene reprogramming urges a re-evaluation of endotoxin tolerance. This review integrates these new findings into an up-to-date account of endotoxin tolerance, its molecular basis and clinical implications in different pathologies.
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Affiliation(s)
- Subhra K Biswas
- Singapore Immunology Network, Biomedical Sciences Institutes, Agency for Science, Technology and Research, #04-01 Immunos, 8A Biomedical Drive, 138648 Singapore.
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Poovassery JS, Vanden Bush TJ, Bishop GA. Antigen receptor signals rescue B cells from TLR tolerance. THE JOURNAL OF IMMUNOLOGY 2009; 183:2974-83. [PMID: 19648281 DOI: 10.4049/jimmunol.0900495] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Interactions between innate and adaptive immune receptors are critical for an optimal immune response, but the role played by Ag receptors in modulating innate receptor functions is less clear. TLRs are a family of pattern recognition receptors that play crucial roles in detecting microbial pathogens and subsequent development of immune responses. However, chronic stimulation through TLRs renders immune cells hyporesponsive to subsequent stimulation with TLR ligands, a phenomenon known as TLR tolerance, well characterized in myeloid cells. However, it has not been studied in detail in B lymphocytes. In addition to the BCR, B cells express almost all known TLRs and respond robustly to many TLR ligands. Thus, B cells may receive signals through both TLRs and BCR during an infection and may respond differently to TLR stimulation than myeloid cells. We tested this possibility by stimulating repeatedly through either TLR alone or both TLR and BCR. Prestimulation through TLR7 resulted in reduced B cell proliferation, cytokine production, and IgM secretion upon subsequent TLR7 restimulation. The hyporesponsiveness to TLR7 restimulation was associated with reduced NF-kappaB and MAPK activation and defective c-Jun phosphorylation. However, simultaneous BCR signaling prevented or reversed TLR7 tolerance in both mouse and human B cells. Importantly, BCR signaling also rescued B cells from TLR7-mediated TLR9 tolerance. Additionally, the reversal of TLR7-mediated JNK activation was dependent on PI3K activation. Together these results present a novel mechanism to prevent and reverse TLR tolerance in B cells.
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Kramer BW, Kallapur SG, Moss TJ, Nitsos I, Newnham JP, Jobe AH. Intra-amniotic LPS modulation of TLR signaling in lung and blood monocytes of fetal sheep. Innate Immun 2009; 15:101-7. [PMID: 19318420 DOI: 10.1177/1753425908100455] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Epidemiological studies suggest that intra-uterine exposure to inflammation may prime postnatal immune responses. In fetal sheep, intra-amniotic injection of lipopolysaccharide (LPS) induced chorioamnionitis, lung inflammation and maturation, matured lung monocytes to macrophages and initiated systemic tolerance of fetal monocytes to subsequent challenge with LPS. We hypothesized that LPS-mediated chorioamnionitis altered the response of lung and blood monocytes to Toll-like receptor (TLR) ligands such as PamCysK4 (TLR2), flagellin (TLR5), and human CpG-DNA (TLR9). Time-mated ewes were given intra-amniotic injections of LPS or saline. Blood and lung monocytes were assessed after 2 days, 7 days and 2 days and 7 days repetitive LPS injections before delivery at 124 days gestational age (term 150 days). Responsiveness of blood and lung monocytes to TLR-ligands in vitro was assessed by interleukin (IL)-6, tumor necrosis factor-alpha (TNF-alpha) and hydrogen peroxide. Monocytes from preterm controls had minimal responses. Lipopolysaccharide-mediated chorioamnionitis increased IL-6, TNF- alpha and hydrogen peroxide to all TLR agonists in blood and lung monocytes. Repetitive exposure to antenatal LPS reduced IL-6, TNF- alpha and hydrogen peroxide to TLR-ligands suggesting tolerance. Tolerance to TLR-ligands reduced IL-1 receptor associated kinase-4 expression. Thus, repeated fetal exposure to LPS induced tolerance to other TLR-ligands. These modulations of fetal innate immunity have implications for host defense and injury responses in preterm infants.
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Affiliation(s)
- Boris W Kramer
- Maastricht University Medical Center, University of Maastricht, Maastricht, The Netherlands.
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Poehlmann H, Schefold JC, Zuckermann-Becker H, Volk HD, Meisel C. Phenotype changes and impaired function of dendritic cell subsets in patients with sepsis: a prospective observational analysis. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2009; 13:R119. [PMID: 19604380 PMCID: PMC2750167 DOI: 10.1186/cc7969] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2009] [Revised: 06/10/2009] [Accepted: 07/15/2009] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Patients with sepsis often demonstrate severely impaired immune responses. The hallmark of this state of immunoparalysis is monocytic deactivation characterized by decreased human leukocyte antigen (HLA)-DR expression and reduced production of proinflammatory cytokines. Recently, diminished numbers of dendritic cells (DCs) were reported in patients with sepsis. However, little is known about DC phenotype and function in human sepsis. We therefore compared phenotypic and functional changes in monocyte and DC subsets in patients with sepsis and immunoparalysis. METHODS In a prospective observational analysis, 16 consecutive patients with severe sepsis and septic shock (age 59.2 +/- 9.7 years, 13 male, Sequential Organ Failure Assessment score 6.1 +/- 2.7) and immunoparalysis (monocytic HLA-DR expression < 5,000 antibodies/cell) and 16 healthy volunteers were included. Peripheral blood DC counts, HLA-DR expression and ex vivo cytokine production were evaluated in comparison with monocyte subsets over time. RESULTS At baseline, a profound reduction in the numbers of myeloid DCs (MDCs), plasmacytoid DCs (PDCs), and CD14dimCD16positive monocytes was observed in sepsis whereas CD14brightCD16negative and CD14brightCD16positive monocyte numbers were increased. HLA-DR expression was reduced on all monocyte and DC subsets. Production of proinflammatory cytokines and intracellular cytokine staining in response to lipopolysaccharide and lipoteichoic acid was impaired in monocyte subsets and MDCs, whereas IL-10 secretion was increased. IFNalpha response by stimulated PDCs was significantly decreased compared with controls. At day 28, HLA-DR expression and cytokine production of DC and monocyte subsets remained lower in septic patients compared with controls. CONCLUSIONS In sepsis, long-lasting functional deactivation is common to all circulating monocyte and DC subsets. In addition to decreased peripheral blood DC counts, functional impairment of antigen-presenting cells may contribute to an impaired antimicrobial defense in sepsis.
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Affiliation(s)
- Holger Poehlmann
- Department of Medical Immunology, Charité Universitätsmedizin Berlin, Campus Mitte, Chariteplatz 1, Berlin 10117, Germany.
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Diverse immune responses to orally administered heat-killed cell preparation of Enterococcus faecalis strain EC-12 in murine immune tissues. Biosci Biotechnol Biochem 2009; 73:1439-42. [PMID: 19502756 DOI: 10.1271/bbb.90010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Diverse immune responses to an orally administered heat-killed cell preparation of Enterococcus faecalis strain EC-12 (EC-12) among jejunal-Peyer's patches (PPs), ileal-PPs, mesenteric lymph nodes (MLNs), and spleen were compared by real-time PCR in mice. Intriguingly, distinct responses to EC-12 were observed in the various tissues. This study indicates a site-specific response to orally administered bacteria, particularly in jejunal- and ileal-PPs.
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Zhang J, Qu JM, He LX. IL-12 suppression, enhanced endocytosis and up-regulation of MHC-II and CD80 in dendritic cells during experimental endotoxin tolerance. Acta Pharmacol Sin 2009; 30:582-8. [PMID: 19349963 DOI: 10.1038/aps.2009.34] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
AIM The aim of this study was to investigate endocytosis, MHC-II expression and co-stimulatory molecule expression, as well as interleukin-12 (IL-12) production, in bone marrow dendritic cells (DCs) derived from endotoxin tolerant mice. METHODS Endotoxin tolerance was induced in C57BL/10J mice through four consecutive daily intraperitoneal injections of 1.0 mg/kg of 055:B5 Escherichia coli lipopolysaccharide (LPS). Bone marrow DCs were isolated in the presence of GM-CSF and IL-4 and purified by anti-CD11c Micro beads. FITC-dextran uptake by DCs was tested by flow cytometric analysis and the percentage of dextran-containing cells was calculated using a fluorescence microscope. The expression of surface MHC-II, CD40, CD80, and CD86 was also detected by flow cytometric analysis. An ELISA was used for the measurement of IL-12 production by DCs with or without LPS stimulation. RESULTS Endotoxin tolerance was successfully induced in C57BL/10J mice, evidenced by an attenuated elevation of systemic TNF-alpha. DCs from endotoxin tolerant mice possessed enhanced dextran endocytosis ability. The expression of surface MHC-II and CD80 was higher in DCs from endotoxin tolerant mice than in DCs from control mice, whereas the expression of CD40 and CD86 was not altered. Compared with DCs from normal control mice, DCs from endotoxin tolerant mice produced less IL-12 after subsequent in vitro stimulation with LPS. CONCLUSION These data suggest enhanced endocytosis, selective up-regulation of MHC-II and CD80 and IL-12 suppression in DCs during in vivo induction of endotoxin tolerance.
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Pène F, Zuber B, Courtine E, Rousseau C, Ouaaz F, Toubiana J, Tazi A, Mira JP, Chiche JD. Dendritic cells modulate lung response to Pseudomonas aeruginosa in a murine model of sepsis-induced immune dysfunction. THE JOURNAL OF IMMUNOLOGY 2009; 181:8513-20. [PMID: 19050269 DOI: 10.4049/jimmunol.181.12.8513] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Host infection by pathogens triggers an innate immune response leading to a systemic inflammatory response, often followed by an immune dysfunction which can favor the emergence of secondary infections. Dendritic cells (DCs) link innate and adaptive immunity and may be centrally involved in the regulation of sepsis-induced immune dysfunction. We assessed the contribution of DCs to lung defense in a murine model of sublethal polymicrobial sepsis (cecal ligature and puncture, CLP). In this model, bone marrow-derived DCs (BMDCs) retained an immature phenotype, associated with decreased capacity of IL-12p70 release and impaired priming of T cell lymphocytes. Eight days after CLP surgery, we induced a secondary pulmonary infection through intratracheal instillation of 5 x 10(6) CFUs of Pseudomonas aeruginosa. Whereas all sham-operated mice survived, 80% of post-CLP mice died after secondary pneumonia. Post-CLP mice exhibited marked lung damage with early recruitment of neutrophils, cytokine imbalance with decreased IL-12p70 production, and increased IL-10 release, but no defective bacterial lung clearance, while systemic bacterial dissemination was almost constant. Concomitant intrapulmonary administration of exogenous BMDCs into post-CLP mice challenged with P. aeruginosa dramatically improved survival. BMDCs did not improve bacterial lung clearance, but delayed neutrophil recruitment, strongly attenuated the early peak of TNF-alpha and restored an adequate Il-12p70/IL-10 balance in post-CLP mice. Thus, adoptive transfer of BMDCs reversed sepsis-induced immune dysfunction in a relevant model of secondary P. aeruginosa pneumonia. Unexpectedly, the mechanism of action of BMDCs did not involve enhanced antibacterial activity, but occurred by dampening the pulmonary inflammatory response.
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Affiliation(s)
- Frédéric Pène
- Department of Cellular Biology, Centre National de la Recherche Scientifique, Cochin Institute, University Paris-Descartes, Paris, France
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Rockwell CE, Morrison DC, Qureshi N. Lipid A-mediated tolerance and cancer therapy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2009; 667:81-99. [PMID: 20665202 DOI: 10.1007/978-1-4419-1603-7_8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The term "tolerance" from an immunological perspective, broadly encompasses a number of phenomena, but generally refers to a diminished responsiveness to LPS and/or other microbial products. With the discovery that many of the immunological, physiological and/or pathophysiological effects of LPS can be attributed to the lipid A moiety of the LPS molecule, a number of different lipid A analogs were synthesized with the goal of developing a drug that could be used clinically to treat cancer. In many instances, the development of tolerance to the lipid A congeners confounded the utility of these analogs as cancer therapeutics. In certain circumstances, however, the development of tolerance in patients has been utilized therapeutically to protect immunosuppressed patients from sepsis. Although numerous studies have been designed to investigate the development of tolerance, the underlying molecular mechanism remains unclear. This may be due, in part, to differences in the experimental models used, the sources and types of microbes and microbial products studied, kinetics of responses, and/or other experimental conditions. Nonetheless, a number of different signaling pathways have been identified as potentially modulating and/or triggering the development of tolerance. Though complex and incompletely understood, the capacity of tolerance to impact lipid A-based therapeutics, either positively or negatively, is inarguable, thus underscoring the necessity for further investigation toward elucidating the mechanisms contributing to the development of tolerance to lipid A and its analogs.
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Affiliation(s)
- Cheryl E Rockwell
- Department of Basic Medical Science, School of Medicine, Shock/Trauma Research Center, University of Missouri, 2411 Holmes Street, Kansas City, MO 64108, USA
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Lenz AM, Turina M, Alard P, Gardner SA, Cheadle WG. Microbial tolerance in secondary peritonitis is dose dependent. Cell Immunol 2009; 258:98-106. [DOI: 10.1016/j.cellimm.2009.03.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2009] [Revised: 03/20/2009] [Accepted: 03/25/2009] [Indexed: 10/20/2022]
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Albrecht V, Hofer TPJ, Foxwell B, Frankenberger M, Ziegler-Heitbrock L. Tolerance induced via TLR2 and TLR4 in human dendritic cells: role of IRAK-1. BMC Immunol 2008; 9:69. [PMID: 19025640 PMCID: PMC2628880 DOI: 10.1186/1471-2172-9-69] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2008] [Accepted: 11/24/2008] [Indexed: 11/20/2022] Open
Abstract
Background While dendritic cells (DCs) can induce tolerance in T cells, little is known about tolerance induction in DCs themselves. We have analysed tolerance induced in human in-vitro generated DCs by repeated stimulation with ligands for TLR4 and TLR2. Results DCs stimulated with the TLR4 ligand LPS did show a rapid and pronounced expression of TNF mRNA and protein. When DCs were pre-cultured for 2 days with 5 ng LPS/ml then the subsequent response to stimulation with a high dose of LPS (500 ng/ml) was strongly reduced for both TNF mRNA and protein. At the promoter level there was a reduced transactivation by the -1173 bp TNF promoter and by a construct with a tetrameric NF-κB motif. Within the signalling cascade leading to NF-κB activation we found an ablation of the IRAK-1 adaptor protein in LPS-tolerant DCs. Pre-culture of DCs with the TLR2 ligand Pam3Cys also led to tolerance with respect to TNF gene expression and IRAK-1 protein was ablated in such tolerant cells as well, while IRAK-4 protein levels were unchanged. Conclusion These data show that TLR-ligands can render DCs tolerant with respect to TNF gene expression by a mechanism that likely involves blockade of signal transduction at the level of IRAK-1.
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Affiliation(s)
- Valerie Albrecht
- Helmholtz Center München, German Research Center for Environmental Health and Asklepios-Fachkliniken Gauting, Inflammatory Lung Diseases, 82131 Gauting, Germany.
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