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Xuan S, Ma Y, Zhou H, Gu S, Yao X, Zeng X. The implication of dendritic cells in lung diseases: Immunological role of toll-like receptor 4. Genes Dis 2024; 11:101007. [PMID: 39238498 PMCID: PMC11375267 DOI: 10.1016/j.gendis.2023.04.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 04/11/2023] [Accepted: 04/17/2023] [Indexed: 09/07/2024] Open
Abstract
The immune responses play a profound role in the progression of lung lesions in both infectious and non-infectious diseases. Dendritic cells, as the "frontline" immune cells responsible for antigen presentation, set up a bridge between innate and adaptive immunity in the course of these diseases. Among the receptors equipped in dendritic cells, Toll-like receptors are a group of specialized receptors as one type of pattern recognition receptors, capable of sensing environmental signals including invading pathogens and self-antigens. Toll-like receptor 4, a pivotal member of the Toll-like receptor family, was formerly recognized as a receptor sensitive to the outer membrane component lipopolysaccharide derived from Gram-negative bacteria, triggering the subsequent response. Moreover, its other essential roles in immune responses have drawn significant attention in the past decade. A better understanding of the implication of Toll-like receptor 4 in dendritic cells could contribute to the management of pulmonary diseases including pneumonia, pulmonary tuberculosis, asthma, acute lung injury, and lung cancer.
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Affiliation(s)
- Shurui Xuan
- Department of Pulmonary & Critical Care Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, China
- Department of Respiratory Medicine, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu 210006, China
| | - Yuan Ma
- Department of Pulmonary & Critical Care Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Honglei Zhou
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Shengwei Gu
- Department of Pulmonary & Critical Care Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Xin Yao
- Department of Pulmonary & Critical Care Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Xiaoning Zeng
- Department of Pulmonary & Critical Care Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, China
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2
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Schorey JS, Vecchio J, McManus WR, Ongalo J, Webber K. Activation of host nucleic acid sensors by Mycobacterium: good for us or good for them? Crit Rev Microbiol 2024; 50:224-240. [PMID: 38153209 PMCID: PMC10985831 DOI: 10.1080/1040841x.2023.2294904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 12/10/2023] [Indexed: 12/29/2023]
Abstract
Although the importance of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) sensors in controlling viral infection is well established, their role in promoting an effective immune response to pathogens other than viruses is less clear. This is particularly true for infections with mycobacteria, as studies point to both protective and detrimental roles for activation of nucleic acid sensors in controlling a mycobacterial infection. Some of the contradiction likely stems from the use of different model systems and different mycobacterial species/strains as well as from which nucleic acid sensors were studied and what downstream effectors were evaluated. In this review, we will describe the different nucleic acid sensors that have been studied in the context of mycobacterial infections, and how the different studies compare. We conclude with a section on how nucleic acid sensor agonists have been used therapeutically and what further information is needed to enhance their potential as therapeutic agents.
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Affiliation(s)
- Jeffery S. Schorey
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556
| | - Joseph Vecchio
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556
| | - William R. McManus
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556
| | - Joshua Ongalo
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556
| | - Kylie Webber
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556
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3
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Li Y, Arai S, Kato K, Iwabuchi S, Iwabuchi N, Muto N, Motobayashi H, Ebihara S, Tanaka M, Hashimoto S. The Potential Immunomodulatory Effect of Bifidobacterium longum subsp. longum BB536 on Healthy Adults through Plasmacytoid Dendritic Cell Activation in the Peripheral Blood. Nutrients 2023; 16:42. [PMID: 38201872 PMCID: PMC10780326 DOI: 10.3390/nu16010042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 12/05/2023] [Accepted: 12/18/2023] [Indexed: 01/12/2024] Open
Abstract
The interaction between the gut microbiota and the host can influence the host's immune system. Bifidobacterium, a commensal genus of gut bacteria, seems to have positive effects on host health. Our previous clinical research showed that B. longum subsp. longum BB536 enhanced innate and adaptive immune responses in elderly individuals with a lower grade of immunity, but the immunomodulatory mechanism is still unclear. In this study, dendritic cell (DC) surface markers in peripheral blood mononuclear cells isolated from healthy individuals were evaluated through coculture with heat-killed BB536. DC markers, innate immune activity and cytokine levels in plasma were also evaluated by a randomized, double-blind, placebo-controlled, parallel-group study (UMIN000045564) with 4 weeks of continuous live BB536 intake. BB536 significantly increased the expression of CD86 and HLA-DR on plasmacytoid DCs (pDCs) in vitro. Compared to placebo (n = 48), a significant increase in the expression of CD86 on peripheral pDCs was detected at week 4 of live BB536 intake (n = 49; 1 × 1010 CFU/day). Furthermore, coculture with hk-BB536 significantly increased the IFNγ expression level and demonstrated trends of increased IFNα1 and IFNβ expression. These findings suggest that consumption of BB536 has potential immunomodulatory effects on healthy individuals through the activation of peripheral pDCs.
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Affiliation(s)
- Yiran Li
- Innovative Research Institute, R&D Division, Morinaga Milk Industry Co., Ltd., 5-1-83, Higashihara, Zama 252-8583, Kanagawa, Japan
| | - Satoshi Arai
- Innovative Research Institute, R&D Division, Morinaga Milk Industry Co., Ltd., 5-1-83, Higashihara, Zama 252-8583, Kanagawa, Japan
| | - Kumiko Kato
- Innovative Research Institute, R&D Division, Morinaga Milk Industry Co., Ltd., 5-1-83, Higashihara, Zama 252-8583, Kanagawa, Japan
| | - Sadahiro Iwabuchi
- Department of Molecular Pathophysiology, Wakayama Medical University, 811-1 Kimiidera, Wakayama 641-8509, Wakayama, Japan
| | - Noriyuki Iwabuchi
- Innovative Research Institute, R&D Division, Morinaga Milk Industry Co., Ltd., 5-1-83, Higashihara, Zama 252-8583, Kanagawa, Japan
| | - Natsumi Muto
- Innovative Research Institute, R&D Division, Morinaga Milk Industry Co., Ltd., 5-1-83, Higashihara, Zama 252-8583, Kanagawa, Japan
| | - Hideki Motobayashi
- Second Department of Surgery, Wakayama Medical University, 811-1 Kimiidera, Wakayama 641-8509, Wakayama, Japan
| | - Shukuko Ebihara
- Chiyoda Paramedical Care Clinic, Daiwa Building 2F, 3-3-10 Nihonbashi Hongokucho, Chuo-ku, Tokyo 103-0021, Japan
| | - Miyuki Tanaka
- Innovative Research Institute, R&D Division, Morinaga Milk Industry Co., Ltd., 5-1-83, Higashihara, Zama 252-8583, Kanagawa, Japan
| | - Shinichi Hashimoto
- Department of Molecular Pathophysiology, Wakayama Medical University, 811-1 Kimiidera, Wakayama 641-8509, Wakayama, Japan
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4
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Casaro S, Prim JG, Gonzalez TD, Bisinotto RS, Chebel RC, Marrero MG, Silva ACM, Santos JEP, Nelson CD, Laporta J, Jeon SJ, Bicalho RC, Driver JP, Galvão KN. Unraveling the immune and metabolic changes associated with metritis in dairy cows. J Dairy Sci 2023; 106:9244-9259. [PMID: 37641354 DOI: 10.3168/jds.2023-23289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 06/11/2023] [Indexed: 08/31/2023]
Abstract
The objective was to unravel the peripartum immune and metabolic changes associated with metritis in Holstein cows. Holstein cows (n = 128) had blood collected at -14, 0, 3, and 7 d relative to parturition (DRP). Flow cytometry was used to evaluate blood leukocyte counts, proportions, and activation. Total cells, live cells, single cells, monocytes (CD172α+/CD14+), polymorphonuclears (CD172α+/CD14-/SSChigh), B-cells (CD21+/MHCII+), CD4+ T-cells (CD4+), CD8+ T-cells (CD8+), and γδ T-cells (γδTCR+) were evaluated. Both CD62L and CD11b were used as markers of cell activation. Major histocompatibility complex class II was used as a marker of antigen presentation in monocytes. A Milliplex Bovine Cytokine/Chemokine 08-plex kit was used to evaluate plasma concentrations of IFN-γ, IL-1α, IL-1β, IL-4, IL-6, IL-8, IL-10, and tumor necrosis factor-α. The body weight (BW) change prepartum was calculated as the difference between calving BW and prepartum BW divided by the number of days between measurements. Plasma fatty acids (FA) were measured at -14 and 0 DRP using untargeted gas chromatography with time-of-flight mass spectrometry. Data were analyzed by ANOVA for repeated measures. Cows that developed metritis (n = 57) had greater prepartum BW, prepartum BW loss, and greater FA concentrations at calving. Plasma FA at calving was positively correlated with IL-1β. Cows that developed metritis had persistent systemic inflammation, which was demonstrated by greater B-cell activation, greater pro-inflammatory cytokine concentrations, and greater cell damage pre- and postpartum. Postpartum, we observed greater polymorphonuclear cell activation and extravasation but lesser monocytes and CD4+ T-cells activation and extravasation, which suggests postpartum immune tolerance. Greater prepartum adiposity in cows that developed metritis may lead to systemic inflammation pre- and postpartum and immune tolerance postpartum, which may lead to failure to prevent bacterial infection, and development of puerperal metritis.
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Affiliation(s)
- S Casaro
- Department of Large Animal Clinical Sciences, University of Florida, Gainesville, FL 32610
| | - J G Prim
- Department of Large Animal Clinical Sciences, University of Florida, Gainesville, FL 32610
| | - T D Gonzalez
- Department of Large Animal Clinical Sciences, University of Florida, Gainesville, FL 32610
| | - R S Bisinotto
- Department of Large Animal Clinical Sciences, University of Florida, Gainesville, FL 32610
| | - R C Chebel
- Department of Large Animal Clinical Sciences, University of Florida, Gainesville, FL 32610
| | - M G Marrero
- Department of Animal Sciences, University of Florida, Gainesville, FL 32610
| | - A C M Silva
- Department of Animal Sciences, University of Florida, Gainesville, FL 32610
| | - J E P Santos
- Department of Animal Sciences, University of Florida, Gainesville, FL 32610; D. H. Barron Reproductive and Perinatal Biology Research Program, University of Florida, Gainesville, FL 32610
| | - C D Nelson
- Department of Animal Sciences, University of Florida, Gainesville, FL 32610; D. H. Barron Reproductive and Perinatal Biology Research Program, University of Florida, Gainesville, FL 32610
| | - J Laporta
- Department of Dairy Sciences, University of Wisconsin-Madison, Madison, WI 53706
| | - S J Jeon
- Department of Veterinary Biomedical Sciences, Long Island University, Brookville, NY 11548
| | - R C Bicalho
- FERA Diagnostics and Biologicals, College Station, TX 77845
| | - J P Driver
- Division of Animals Sciences, University of Missouri-Columbia, Columbia, MO 65211
| | - K N Galvão
- Department of Large Animal Clinical Sciences, University of Florida, Gainesville, FL 32610; D. H. Barron Reproductive and Perinatal Biology Research Program, University of Florida, Gainesville, FL 32610.
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5
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Höpfinger A, Schmid A, Schweitzer L, Patz M, Weber A, Schäffler A, Karrasch T. Regulation of Cathelicidin Antimicrobial Peptide (CAMP) Gene Expression by TNFα and cfDNA in Adipocytes. Int J Mol Sci 2023; 24:15820. [PMID: 37958808 PMCID: PMC10649744 DOI: 10.3390/ijms242115820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 10/16/2023] [Accepted: 10/21/2023] [Indexed: 11/15/2023] Open
Abstract
Understanding the complex interactions between metabolism and the immune system ("metaflammation") is crucial for the identification of key immunomodulatory factors as potential therapeutic targets in obesity and in cardiovascular diseases. Cathelicidin antimicrobial peptide (CAMP) is an important factor of innate immunity and is expressed in adipocytes. CAMP, therefore, might play a role as an adipokine in metaflammation and adipose inflammation. TNFα, cell-free nucleic acids (cfDNA), and toll-like receptor (TLR) 9 are components of the innate immune system and are functionally active in adipose tissue. The aim of the present study was to investigate the impact of TNFα and cfDNA on CAMP expression in adipocytes. Since cfDNA acts as a physiological TLR9 agonist, we additionally investigated TLR9-mediated CAMP regulation in adipocytes and adipose tissue. CAMP gene expression in murine 3T3-L1 and human SGBS adipocytes and in murine and human adipose tissues was quantified by real-time PCR. Adipocyte inflammation was induced in vitro by TNFα and cfDNA stimulation. Serum CAMP concentrations in TLR9 knockout (KO) and in wildtype mice were quantified by ELISA. In primary adipocytes of wildtype and TLR9 KO mice, CAMP gene expression was quantified by real-time PCR. CAMP gene expression was considerably increased in 3T3-L1 and SGBS adipocytes during differentiation. TNFα significantly induced CAMP gene expression in mature adipocytes, which was effectively antagonized by inhibition of PI3K signaling. Cell-free nucleic acids (cfDNA) significantly impaired CAMP gene expression, whereas synthetic agonistic and antagonistic TLR9 ligands had no effect. CAMP and TLR9 gene expression were correlated positively in murine and human subcutaneous but not in intra-abdominal/visceral adipose tissues. Male TLR9 knockout mice exhibited lower systemic CAMP concentrations than wildtype mice. CAMP gene expression levels in primary adipocytes did not significantly differ between wildtype and TLR9 KO mice. These findings suggest a regulatory role of inflammatory mediators, such as TNFα and cfDNA, in adipocytic CAMP expression as a novel putative molecular mechanism in adipose tissue innate immunity.
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Affiliation(s)
- Alexandra Höpfinger
- Department of Internal Medicine III, University of Giessen, 35392 Giessen, Germany (A.S.); (T.K.)
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6
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Emami MR, Espinoza A, Young CS, Ma F, Farahat PK, Felgner PL, Chamberlain JS, Xu X, Pyle AD, Pellegrini M, Villalta SA, Spencer MJ. Innate and adaptive AAV-mediated immune responses in a mouse model of Duchenne muscular dystrophy. Mol Ther Methods Clin Dev 2023; 30:90-102. [PMID: 37746243 PMCID: PMC10512012 DOI: 10.1016/j.omtm.2023.06.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 06/08/2023] [Indexed: 09/26/2023]
Abstract
High systemic doses of adeno-associated viruses (AAVs) have been associated with immune-related serious adverse events (SAEs). Although AAV was well tolerated in preclinical models, SAEs were observed in clinical trials, indicating the need for improved preclinical models to understand AAV-induced immune responses. Here, we show that mice dual-dosed with AAV9 at 4-week intervals better recapitulate aspects of human immunity to AAV. In the model, anti-AAV9 immunoglobulin G (IgGs) increased in a linear fashion between the first and second AAV administrations. Complement activation was only observed in the presence of high levels of both AAV and anti-AAV IgG. Myeloid-derived pro-inflammatory cytokines were significantly induced in the same pattern as complement activation, suggesting that myeloid cell activation to AAV may rely on the presence of both AAV and anti-AAV IgG complexes. Single-cell RNA sequencing of peripheral blood mononuclear cells confirmed that activated monocytes were a primary source of pro-inflammatory cytokines and chemokines, which were significantly increased after a second AAV9 exposure. The same activated monocyte clusters expressed both Fcγ and complement receptors, suggesting that anti-AAV-mediated activation of myeloid cells through Fcγ receptors and/or complement receptors is one mechanism by which anti-AAV antigen complexes may prime antigen-presenting cells and amplify downstream immunity.
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Affiliation(s)
- Michael R. Emami
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Alejandro Espinoza
- Department of Human Genetics, University of California, Los Angeles, Los Angeles, CA, USA
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, USA
- Institute for Quantitative and Computational Biosciences – The Collaboratory, University of California, Los Angeles, Los Angeles, CA, USA
| | | | - Feiyang Ma
- Division of Rheumatology, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Philip K. Farahat
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA, USA
| | - Philip L. Felgner
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA, USA
| | - Jeffrey S. Chamberlain
- Department of Neurology, University of Washington School of Medicine, Seattle, WA, USA
- Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Washington School of Medicine, Seattle, WA, USA
- Department of Biochemistry, University of Washington School of Medicine, Seattle, WA, USA
- Department of Medicine, University of Washington School of Medicine, Seattle, WA, USA
| | - Xiangmin Xu
- Department of Anatomy and Neurobiology, School of Medicine, University of California, Irvine, Irvine, CA, USA
| | - April D. Pyle
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, USA
- Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, Los Angeles, CA, USA
| | - Matteo Pellegrini
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, USA
- Institute for Genomics and Proteomics, University of California, Los Angeles, Los Angeles, CA, USA
| | - S. Armando Villalta
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA, USA
- Institute of Immunology, University of California, Irvine, Irvine, CA, USA
- Department of Neurology, University of California, Irvine, Irvine, CA, USA
| | - Melissa J. Spencer
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
- Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, Los Angeles, CA, USA
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7
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CXCR4 signaling controls dendritic cell location and activation at steady state and in inflammation. Blood 2021; 137:2770-2784. [PMID: 33512478 DOI: 10.1182/blood.2020006675] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 12/20/2020] [Indexed: 12/12/2022] Open
Abstract
Dendritic cells (DCs) encompass several cell subsets that collaborate to initiate and regulate immune responses. Proper DC localization determines their function and requires the tightly controlled action of chemokine receptors. All DC subsets express CXCR4, but the genuine contribution of this receptor to their biology has been overlooked. We addressed this question using natural CXCR4 mutants resistant to CXCL12-induced desensitization and harboring a gain of function that cause the warts, hypogammaglobulinemia, infections, and myelokathexis (WHIM) syndrome (WS), a rare immunodeficiency associated with high susceptibility to the pathogenesis of human papillomavirus (HPV). We report a reduction in the number of circulating plasmacytoid DCs (pDCs) in WHIM patients, whereas that of conventional DCs is preserved. This pattern was reproduced in an original mouse model of WS, enabling us to show that the circulating pDC defect can be corrected upon CXCR4 blockade and that pDC differentiation and function are preserved, despite CXCR4 dysfunction. We further identified proper CXCR4 signaling as a critical checkpoint for Langerhans cell and DC migration from the skin to lymph nodes, with corollary alterations of their activation state and tissue inflammation in a model of HPV-induced dysplasia. Beyond providing new hypotheses to explain the susceptibility of WHIM patients to HPV pathogenesis, this study shows that proper CXCR4 signaling establishes a migration threshold that controls DC egress from CXCL12-containing environments and highlights the critical and subset-specific contribution of CXCR4 signal termination to DC biology.
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8
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Fevereiro J, Fraga AG, Pedrosa J. Genetics in the Host-Mycobacterium ulcerans interaction. Immunol Rev 2021; 301:222-241. [PMID: 33682158 DOI: 10.1111/imr.12958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 01/30/2021] [Accepted: 02/01/2021] [Indexed: 11/30/2022]
Abstract
Buruli ulcer is an emerging infectious disease associated with high morbidity and unpredictable outbreaks. It is caused by Mycobacterium ulcerans, a slow-growing pathogen evolutionarily shaped by the acquisition of a plasmid involved in the production of a potent macrolide-like cytotoxin and by genome rearrangements and downsizing. These events culminated in an uncommon infection pattern, whereby M. ulcerans is both able to induce the initiation of the inflammatory cascade and the cell death of its proponents, as well as to survive within the phagosome and in the extracellular milieu. In such extreme conditions, the host is sentenced to rely on a highly orchestrated genetic landscape to be able to control the infection. We here revisit the dynamics of M. ulcerans infection, drawing parallels from other mycobacterioses and integrating the most recent knowledge on its evolution and pathogenicity in its interaction with the host immune response.
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Affiliation(s)
- João Fevereiro
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Alexandra G Fraga
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Jorge Pedrosa
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
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Yang H, Chen J, Chen Y, Jiang Y, Ge B, Hong L. Sirt1 activation negatively regulates overt apoptosis in Mtb-infected macrophage through Bax. Int Immunopharmacol 2021; 91:107283. [PMID: 33373810 DOI: 10.1016/j.intimp.2020.107283] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 11/25/2020] [Accepted: 12/04/2020] [Indexed: 01/18/2023]
Abstract
Apoptotic pathways play an important role in Mycobacterium tuberculosis-infected macrophages. Sirt1 is a member of the deacetylase family that is known to promote apoptosis resistance in many mammalian cells. However, the apoptotic role of Sirt1 in the process of M. tuberculosis infection remains unclear. With the help of mouse macrophage samples, 129/Sv background mice, and PBMCs-derived macrophages from healthy controls and patients with tuberculosis, we have shown that M. tuberculosis infection reduced Sirt1 mRNA and protein expression, however, increased Bax mRNA and protein expression. Further, we found that resveratrol, a Sirt1 activator, inhibited M. tuberculosis-induced Bax expression. Thus, it seems that Sirt1 acts as a novel regulator of apoptosis signaling in M. tuberculosis infection via its effects on Bax. Sirt1 activation may therefore be a new candidate for the prevention and treatment of tuberculosis.
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Affiliation(s)
- Hong Yang
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai 200092, China; Clinical Translational Research Center, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China; Shanghai TB Key Laboratory, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China.
| | - Jianxia Chen
- Clinical Translational Research Center, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China; Shanghai TB Key Laboratory, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China
| | - Yanghaoyu Chen
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Yan Jiang
- Clinical Translational Research Center, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China; Shanghai TB Key Laboratory, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China
| | - Baoxue Ge
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai 200092, China; Clinical Translational Research Center, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China; Shanghai TB Key Laboratory, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China
| | - Ling Hong
- Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai 201204, China.
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10
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Janosevic D, Myslinski J, McCarthy TW, Zollman A, Syed F, Xuei X, Gao H, Liu YL, Collins KS, Cheng YH, Winfree S, El-Achkar TM, Maier B, Melo Ferreira R, Eadon MT, Hato T, Dagher PC. The orchestrated cellular and molecular responses of the kidney to endotoxin define a precise sepsis timeline. eLife 2021; 10:62270. [PMID: 33448928 PMCID: PMC7810465 DOI: 10.7554/elife.62270] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 12/13/2020] [Indexed: 12/14/2022] Open
Abstract
Sepsis is a dynamic state that progresses at variable rates and has life-threatening consequences. Staging patients along the sepsis timeline requires a thorough knowledge of the evolution of cellular and molecular events at the tissue level. Here, we investigated the kidney, an organ central to the pathophysiology of sepsis. Single-cell RNA-sequencing in a murine endotoxemia model revealed the involvement of various cell populations to be temporally organized and highly orchestrated. Endothelial and stromal cells were the first responders. At later time points, epithelial cells upregulated immune-related pathways while concomitantly downregulating physiological functions such as solute homeostasis. Sixteen hours after endotoxin, there was global cell–cell communication failure and organ shutdown. Despite this apparent organ paralysis, upstream regulatory analysis showed significant activity in pathways involved in healing and recovery. This rigorous spatial and temporal definition of murine endotoxemia will uncover precise biomarkers and targets that can help stage and treat human sepsis.
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Affiliation(s)
- Danielle Janosevic
- Department of Medicine, Indiana University School of Medicine, Indianapolis, United States
| | - Jered Myslinski
- Department of Medicine, Indiana University School of Medicine, Indianapolis, United States
| | - Thomas W McCarthy
- Department of Medicine, Indiana University School of Medicine, Indianapolis, United States
| | - Amy Zollman
- Department of Medicine, Indiana University School of Medicine, Indianapolis, United States
| | - Farooq Syed
- Department of Pediatrics and the Herman B. Wells Center, Indiana University School of Medicine, Indianapolis, United States
| | - Xiaoling Xuei
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, United States
| | - Hongyu Gao
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, United States
| | - Yun-Long Liu
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, United States
| | - Kimberly S Collins
- Department of Medicine, Indiana University School of Medicine, Indianapolis, United States
| | - Ying-Hua Cheng
- Department of Medicine, Indiana University School of Medicine, Indianapolis, United States
| | - Seth Winfree
- Department of Medicine, Indiana University School of Medicine, Indianapolis, United States
| | - Tarek M El-Achkar
- Department of Medicine, Indiana University School of Medicine, Indianapolis, United States.,Roudebush Indianapolis Veterans Affairs Medical Center, Indianapolis, United States
| | - Bernhard Maier
- Department of Medicine, Indiana University School of Medicine, Indianapolis, United States
| | - Ricardo Melo Ferreira
- Department of Medicine, Indiana University School of Medicine, Indianapolis, United States
| | - Michael T Eadon
- Department of Medicine, Indiana University School of Medicine, Indianapolis, United States
| | - Takashi Hato
- Department of Medicine, Indiana University School of Medicine, Indianapolis, United States
| | - Pierre C Dagher
- Department of Medicine, Indiana University School of Medicine, Indianapolis, United States.,Roudebush Indianapolis Veterans Affairs Medical Center, Indianapolis, United States
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11
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Psarras A, Antanaviciute A, Alase A, Carr I, Wittmann M, Emery P, Tsokos GC, Vital EM. TNF-α Regulates Human Plasmacytoid Dendritic Cells by Suppressing IFN-α Production and Enhancing T Cell Activation. THE JOURNAL OF IMMUNOLOGY 2021; 206:785-796. [PMID: 33441439 PMCID: PMC7851743 DOI: 10.4049/jimmunol.1901358] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 11/25/2020] [Indexed: 12/29/2022]
Abstract
TNF downregulates IFN-α and TNF production by human pDCs. TNF downregulates IRF7 and NF-κB pathways and upregulates Ag processing in pDCs. TNF enhances Ag presentation and T cell activation properties in pDCs.
Human plasmacytoid dendritic cells (pDCs) play a vital role in modulating immune responses. They can produce massive amounts of type I IFNs in response to nucleic acids via TLRs, but they are also known to possess weak Ag-presenting properties inducing CD4+ T cell activation. Previous studies showed a cross-regulation between TNF-α and IFN-α, but many questions remain about the effect of TNF-α in regulating human pDCs. In this study, we showed that TNF-α significantly inhibited the secretion of IFN-α and TNF-α of TLR-stimulated pDCs. Instead, exogenous TNF-α promoted pDC maturation by upregulating costimulatory molecules and chemokine receptors such as CD80, CD86, HLA-DR, and CCR7. Additionally, RNA sequencing analysis showed that TNF-α inhibited IFN-α and TNF-α production by downregulating IRF7 and NF-κB pathways, while it promoted Ag processing and presentation pathways as well as T cell activation and differentiation. Indeed, TNF-α–treated pDCs induced in vitro higher CD4+ T cell proliferation and activation, enhancing the production of Th1 and Th17 cytokines. In conclusion, TNF-α favors pDC maturation by switching their main role as IFN-α–producing cells to a more conventional dendritic cell phenotype. The functional status of pDCs might therefore be strongly influenced by their overall inflammatory environment, and TNF-α might regulate IFN-α–mediated aspects of a range of autoimmune and inflammatory diseases.
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Affiliation(s)
- Antonios Psarras
- Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds LS7 4SA, United Kingdom.,National Institute for Health Research Leeds Biomedical Research Centre, Leeds Teaching Hospitals NHS Trust, Leeds LS7 4SA, United Kingdom.,Division of Rheumatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215; and
| | - Agne Antanaviciute
- Leeds Institute for Data Analytics, University of Leeds, Leeds LS9 7TF, United Kingdom
| | - Adewonuola Alase
- Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds LS7 4SA, United Kingdom.,National Institute for Health Research Leeds Biomedical Research Centre, Leeds Teaching Hospitals NHS Trust, Leeds LS7 4SA, United Kingdom
| | - Ian Carr
- Leeds Institute for Data Analytics, University of Leeds, Leeds LS9 7TF, United Kingdom
| | - Miriam Wittmann
- Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds LS7 4SA, United Kingdom.,National Institute for Health Research Leeds Biomedical Research Centre, Leeds Teaching Hospitals NHS Trust, Leeds LS7 4SA, United Kingdom
| | - Paul Emery
- Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds LS7 4SA, United Kingdom.,National Institute for Health Research Leeds Biomedical Research Centre, Leeds Teaching Hospitals NHS Trust, Leeds LS7 4SA, United Kingdom
| | - George C Tsokos
- Division of Rheumatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215; and
| | - Edward M Vital
- Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds LS7 4SA, United Kingdom; .,National Institute for Health Research Leeds Biomedical Research Centre, Leeds Teaching Hospitals NHS Trust, Leeds LS7 4SA, United Kingdom
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12
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Yang H, Chen J, Chen Y, Jiang Y, Ge B, Hong L. Sirtuin inhibits M. tuberculosis -induced apoptosis in macrophage through glycogen synthase kinase-3β. Arch Biochem Biophys 2020; 694:108612. [PMID: 33007281 DOI: 10.1016/j.abb.2020.108612] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/05/2020] [Accepted: 09/27/2020] [Indexed: 12/22/2022]
Abstract
Apoptotic and inflammatory pathways play important roles in Mycobacterium tuberculosis-infected macrophages. Sirt1 is a member of the deacetylase family that is known to promote apoptosis resistance in mammalian cells and was recently reported to regulate mycobacterial immunopathogenesis via inflammatory responses. However, the apoptotic role of Sirt1 in the process of M. tuberculosis infection remains unclear. With the help of mouse peritoneal macrophage samples, we have shown that resveratrol, a Sirt1 activator, inhibited M. tuberculosis-induced apoptosis in peritoneal macrophages. Further, we found that Sirt1 activation prompted M. tuberculosis induced GSK3β phosphorylation. Further investigation into the possible mechanisms of action showed that Sirt1 directly interacted with GSK3β and enhanced GSK3β phosphorylation by promoting its deacetylation. Sirt1 activation inhibited M. tuberculosis growth. Thus, it seemed that Sirt1 acted as a novel regulator of apoptosis signaling in M. tuberculosis infection via its direct effects on GSK3β. Sirt1 may therefore be a new candidate for the prevention and treatment of tuberculosis.
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Affiliation(s)
- Hong Yang
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, 200092, China; Clinical Translational Research Center, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200433, China; Shanghai TB Key Laboratory, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200433, China.
| | - Jianxia Chen
- Clinical Translational Research Center, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200433, China; Shanghai TB Key Laboratory, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200433, China
| | - Yanghaoyu Chen
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Yan Jiang
- Clinical Translational Research Center, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200433, China; Shanghai TB Key Laboratory, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200433, China
| | - Baoxue Ge
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, 200092, China; Clinical Translational Research Center, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200433, China; Shanghai TB Key Laboratory, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200433, China
| | - Ling Hong
- Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, 201204, China.
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13
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Bagadia P, Huang X, Liu TT, Murphy KM. Shared Transcriptional Control of Innate Lymphoid Cell and Dendritic Cell Development. Annu Rev Cell Dev Biol 2019; 35:381-406. [PMID: 31283378 PMCID: PMC6886469 DOI: 10.1146/annurev-cellbio-100818-125403] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Innate immunity and adaptive immunity consist of highly specialized immune lineages that depend on transcription factors for both function and development. In this review, we dissect the similarities between two innate lineages, innate lymphoid cells (ILCs) and dendritic cells (DCs), and an adaptive immune lineage, T cells. ILCs, DCs, and T cells make up four functional immune modules and interact in concert to produce a specified immune response. These three immune lineages also share transcriptional networks governing the development of each lineage, and we discuss the similarities between ILCs and DCs in this review.
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Affiliation(s)
- Prachi Bagadia
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63108, USA;
| | - Xiao Huang
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63108, USA;
| | - Tian-Tian Liu
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63108, USA;
| | - Kenneth M Murphy
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63108, USA;
- Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri 63108, USA
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14
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Immunology of Plasmacytoid Dendritic Cells in Solid Tumors: A Brief Review. Cancers (Basel) 2019; 11:cancers11040470. [PMID: 30987228 PMCID: PMC6520684 DOI: 10.3390/cancers11040470] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 03/30/2019] [Accepted: 04/01/2019] [Indexed: 01/06/2023] Open
Abstract
The immune response, both innate and adaptive, is a key player in cancer development and progression. Plasmacytoid dendritic cells (pDCs) are a subset of dendritic cells that play one of the central roles in the immune system. They are known mostly as the major IFN type I-producing cells upon stimulation of Toll-like receptors 7 and 9. However, based on current knowledge, the functionality of pDCs is very complex, as they have the ability to affect many other cell types. In the context of the tumor tissue, pDCs were mostly described to show substantial functional defects and therefore contribute to the establishement of immunosuppressive tumor microenvironment. Immunotherapeutic approaches have proven to be one of the most promising treatment strategies in the last decade. In view of this fact, it is crucial to map the complexity of the tumor microenvironment in detail, including less numerous cell types. This review focuses on pDCs in relation to solid tumors. We provide a summary of current data on the role of pDCs in different tumor types and suggest their possible clinical applications.
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15
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Thomalla M, Schmid A, Neumann E, Pfefferle PI, Müller-Ladner U, Schäffler A, Karrasch T. Evidence of an anti-inflammatory toll-like receptor 9 (TLR 9) pathway in adipocytes. J Endocrinol 2019; 240:325-343. [PMID: 30508414 DOI: 10.1530/joe-18-0326] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 11/30/2018] [Indexed: 12/17/2022]
Abstract
Adipocytes express various pattern recognition receptors (PRRs) such as Toll-like receptors (TLRs) and actively participate in anti-bacterial and anti-viral host defence. Obesity is associated with adipose tissue PRR expression. The potential role of Toll-like receptor 9 (TLR9) in adipocytes has not yet been investigated. Here, we evaluated TLR9 expression during adipocyte differentiation (AD) of 3T3-L1 adipocytes, in primary murine adipocytes and in different murine and human adipose tissue depots by real-time PCR, immunocytochemistry and immunohistochemistry. TLR9 expression was inhibited using specific siRNA-mediated knockdown, and TLR9 signaling was induced using specific class A, B and C agonistic CpG-oligodeoxynucleotide (ODN) treatment vs ODN controls in 3T3-L1 adipocytes and in primary murine adipocytes from Tlr9wt/wt vs Tlr9-/- mice. We found that TLR9 gene expression is induced during AD and that TLR9 protein is expressed in murine gonadal and human visceral adipocytes. AD depends on intact TLR9 expression. Tlr9-/- mice demonstrate significantly reduced adiponectin serum levels, while siRNA-mediated TLR9 knockdown led to reduced adiponectin mRNA expression in adipocytes. TLR9 ligands (CpG-ODNs) inhibit pro-inflammatory resistin secretion in mature 3T3-L1 adipocytes. Tlr9-/- as compared to Tlr9wt/wt adipocytes exhibit increased resistin and MCP1 secretion and reduced adiponectin secretion into cell culture supernatants, while TLR9 ligands (ODNs) show differential effects in Tlr9-/- vs Tlr9wt/wt primary murine adipocytes. TLR9 expression is significantly increased in visceral compared to subcutaneous adipose tissue depots in non-diabetic obese patients and correlates with systemic resistin levels in a compartment-specific manner. Thus, adipocytic TLR9 is a putative, new protective factor during (obesity-associated) adipose tissue inflammation.
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Affiliation(s)
- Miriam Thomalla
- Department of Internal Medicine III, Giessen University Hospital, Giessen, Germany
| | - Andreas Schmid
- Department of Internal Medicine III, Giessen University Hospital, Giessen, Germany
| | - Elena Neumann
- Department of Rheumatology and Clinical Immunology, University of Giessen and Kerckhoff Clinic, Bad Nauheim, Germany
| | - Petra Ina Pfefferle
- Comprehensive Biomaterial Bank Marburg (CBBMR), Philipps-University of Marburg, Marburg, Germany
| | - Ulf Müller-Ladner
- Department of Rheumatology and Clinical Immunology, University of Giessen and Kerckhoff Clinic, Bad Nauheim, Germany
| | - Andreas Schäffler
- Department of Internal Medicine III, Giessen University Hospital, Giessen, Germany
| | - Thomas Karrasch
- Department of Internal Medicine III, Giessen University Hospital, Giessen, Germany
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16
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Reizis B. Plasmacytoid Dendritic Cells: Development, Regulation, and Function. Immunity 2019; 50:37-50. [PMID: 30650380 PMCID: PMC6342491 DOI: 10.1016/j.immuni.2018.12.027] [Citation(s) in RCA: 369] [Impact Index Per Article: 73.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 12/17/2018] [Accepted: 12/20/2018] [Indexed: 12/14/2022]
Abstract
Plasmacytoid dendritic cells (pDCs) are a unique sentinel cell type that can detect pathogen-derived nucleic acids and respond with rapid and massive production of type I interferon. This review summarizes our current understanding of pDC biology, including transcriptional regulation, heterogeneity, role in antiviral immune responses, and involvement in immune pathology, particularly in autoimmune diseases, immunodeficiency, and cancer. We also highlight the remaining gaps in our knowledge and important questions for the field, such as the molecular basis of unique interferon-producing capacity of pDCs. A better understanding of cell type-specific positive and negative control of pDC function should pave the way for translational applications focused on this immune cell type.
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Affiliation(s)
- Boris Reizis
- Department of Pathology and Department of Medicine, New York University School of Medicine, New York, NY 10016, USA.
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17
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Webster B, Werneke SW, Zafirova B, This S, Coléon S, Décembre E, Paidassi H, Bouvier I, Joubert PE, Duffy D, Walzer T, Albert ML, Dreux M. Plasmacytoid dendritic cells control dengue and Chikungunya virus infections via IRF7-regulated interferon responses. eLife 2018; 7:34273. [PMID: 29914621 PMCID: PMC6008049 DOI: 10.7554/elife.34273] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 04/30/2018] [Indexed: 01/01/2023] Open
Abstract
Type I interferon (IFN-I) responses are critical for the control of RNA virus infections, however, many viruses, including Dengue (DENV) and Chikungunya (CHIKV) virus, do not directly activate plasmacytoid dendritic cells (pDCs), robust IFN-I producing cells. Herein, we demonstrated that DENV and CHIKV infected cells are sensed by pDCs, indirectly, resulting in selective IRF7 activation and IFN-I production, in the absence of other inflammatory cytokine responses. To elucidate pDC immunomodulatory functions, we developed a mouse model in which IRF7 signaling is restricted to pDC. Despite undetectable levels of IFN-I protein, pDC-restricted IRF7 signaling controlled both viruses and was sufficient to protect mice from lethal CHIKV infection. Early pDC IRF7-signaling resulted in amplification of downstream antiviral responses, including an accelerated natural killer (NK) cell-mediated type II IFN response. These studies revealed the dominant, yet indirect role of pDC IRF7-signaling in directing both type I and II IFN responses during arbovirus infections. Viruses, like the ones responsible for the tropical diseases dengue and chikungunya, are parasites of living cells. As they cannot multiply on their own, these microbes need to infect a host cell and hijack its machinery to make more of themselves. When a cell is invaded, it can sense the viral particles, and defend itself by releasing antiviral molecules. Some of these molecules, such as interferons, also help recruit immune cells that can fight the germs. However, viruses often evolve mechanisms to escape being detected by the cell they occupy. Plasmacytoid dendritic cells are a rare group of immune cells, and they are able to detect when another cell is infected by the dengue virus. When they are in close physical contact with an invaded cell, these sentinels can recognize immature viral particles and release large amounts of antiviral molecules. However, it is unclear how important plasmacytoid dendritic cells are in clearing a viral infection. Here, Webster, Werneke et al. confirmed that plasmacytoid dendritic cells were able to sense cells infected by dengue, but also by chikungunya. When this happened, the dendritic cells primarily produced interferon, rather than other defense molecules. In addition, mice were genetically engineered so that the production of interferon was restricted to the plasmacytoid dendritic cells. When infected with dengue or chikungunya, the modified rodents resisted the diseases. These results show that, even though they are only a small percentage of all immune cells, plasmacytoid dendritic cells have an outsize role as first responders and as coordinators of the immune response. Finally, Webster, Werneke et al. showed that when low doses of interferon are added, , the plasmacytoid dendritic cells respond more quickly to cells infected by dengue. Together these findings could potentially be leveraged to create new treatments to fight dengue. These would be of particular interest because interferons are not as damaging to the body compared to other types of defense molecules. The issue is timely since climate change is allowing the mosquitos that transmit dengue and chikungunya to live in new places, exposing more people to these serious infections.
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Affiliation(s)
- Brian Webster
- CIRI, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Univ Lyon, Lyon, France
| | - Scott W Werneke
- Immunobiology of Dendritic Cells, Institut Pasteur, Paris, France.,Cancer Immunology Department, Genentech, San Francisco, United States
| | - Biljana Zafirova
- Immunobiology of Dendritic Cells, Institut Pasteur, Paris, France
| | - Sébastien This
- CIRI, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Univ Lyon, Lyon, France
| | - Séverin Coléon
- CIRI, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Univ Lyon, Lyon, France
| | - Elodie Décembre
- CIRI, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Univ Lyon, Lyon, France
| | - Helena Paidassi
- CIRI, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Univ Lyon, Lyon, France
| | - Isabelle Bouvier
- Immunobiology of Dendritic Cells, Institut Pasteur, Paris, France
| | | | - Darragh Duffy
- Immunobiology of Dendritic Cells, Institut Pasteur, Paris, France
| | - Thierry Walzer
- CIRI, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Univ Lyon, Lyon, France
| | - Matthew L Albert
- Immunobiology of Dendritic Cells, Institut Pasteur, Paris, France.,Cancer Immunology Department, Genentech, San Francisco, United States
| | - Marlène Dreux
- CIRI, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Univ Lyon, Lyon, France
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18
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Mitochondrial reactive oxygen species regulate the induction of CD8 + T cells by plasmacytoid dendritic cells. Nat Commun 2018; 9:2241. [PMID: 29884826 PMCID: PMC5993805 DOI: 10.1038/s41467-018-04686-8] [Citation(s) in RCA: 112] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 05/14/2018] [Indexed: 01/14/2023] Open
Abstract
Cross-presentation allows exogenous antigen presentation in association with major histocompatibility complex class I molecules, a process crucial for the priming of CD8+ T-cell responses against viruses and tumors. By contrast to conventional dendritic cells (cDC), which cross-present antigens in the steady state, plasmacytoid dendritic cells (pDC) acquire this ability only after stimulation by Toll-like receptor (TLR) ligands. The intracellular pathways accounting for this functional difference are still unknown. Here we show that the induction of cross-presentation by pDCs is regulated by mitochondria through a reactive oxygen species (ROS)-dependent mechanism, involving pH alkalization and antigen protection. The reduction of mitochondrial ROS production dramatically decreases the cross-presentation capacity of pDCs, leading to a strong reduction of their capacity to trigger CD8+ T-cell responses. Our results demonstrate the importance of mitochondrial metabolism in pDC biology, particularly for the induction of adaptive immune responses.
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19
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Terra M, Oberkampf M, Fayolle C, Rosenbaum P, Guillerey C, Dadaglio G, Leclerc C. Tumor-Derived TGFβ Alters the Ability of Plasmacytoid Dendritic Cells to Respond to Innate Immune Signaling. Cancer Res 2018. [PMID: 29523540 DOI: 10.1158/0008-5472.can-17-2719] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A growing number of observations has suggested that plasmacytoid dendritic cells (pDC) play a critical role in tumor biology. In patients, infiltration of tumors by pDCs generally correlates with a poor prognosis, suggesting that pDCs may play an important role in the host-tumor relationship. Here, we analyze the influence of pDCs in solid tumor development using two different tumor models: TC-1 and B16-OVA. Phenotypic and functional gene profiling analysis of tumor-associated pDCs showed that the tumor microenvironment affected their activation status and ability to produce cytokines and chemokines. In addition, tumor cells secreted factors that inhibit the ability of pDCs to produce type I IFN. Among the various cytokines and chemokines produced by the tumor cells, we demonstrate that TGFβ is the main factor responsible for this inhibition. Using a mouse model deficient for pDCs, we also show that pDCs promote TC-1 tumor growth and that natural killer (NK) cells and regulatory T cells are involved in the protumoral effect of pDCs. Overall, our results evidence the cross-talk among pDCs, NK, and regulatory T cells in the promotion of tumor growth and their role in the development of antitumor immune responses.Significance: These findings highlight the importance of pDCs in the cross-talk between tumor cells and the immune system. Cancer Res; 78(11); 3014-26. ©2018 AACR.
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Affiliation(s)
- Mariana Terra
- Institut Pasteur, Unité de Régulation Immunitaire et Vaccinologie, Equipe Labellisée Ligue Contre le Cancer, Paris, France.,INSERM U1041, Paris, France.,Université Paris-Diderot, Sorbonne Paris Cité, Paris, France
| | - Marine Oberkampf
- Institut Pasteur, Unité de Régulation Immunitaire et Vaccinologie, Equipe Labellisée Ligue Contre le Cancer, Paris, France.,INSERM U1041, Paris, France
| | - Catherine Fayolle
- Institut Pasteur, Unité de Régulation Immunitaire et Vaccinologie, Equipe Labellisée Ligue Contre le Cancer, Paris, France.,INSERM U1041, Paris, France
| | - Pierre Rosenbaum
- Institut Pasteur, Unité de Régulation Immunitaire et Vaccinologie, Equipe Labellisée Ligue Contre le Cancer, Paris, France.,INSERM U1041, Paris, France
| | - Camille Guillerey
- Institut Pasteur, Unité de Régulation Immunitaire et Vaccinologie, Equipe Labellisée Ligue Contre le Cancer, Paris, France.,INSERM U1041, Paris, France
| | - Gilles Dadaglio
- Institut Pasteur, Unité de Régulation Immunitaire et Vaccinologie, Equipe Labellisée Ligue Contre le Cancer, Paris, France. .,INSERM U1041, Paris, France
| | - Claude Leclerc
- Institut Pasteur, Unité de Régulation Immunitaire et Vaccinologie, Equipe Labellisée Ligue Contre le Cancer, Paris, France. .,INSERM U1041, Paris, France
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20
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von Stebut E, Tenzer S. Cutaneous leishmaniasis: Distinct functions of dendritic cells and macrophages in the interaction of the host immune system with Leishmania major. Int J Med Microbiol 2017; 308:206-214. [PMID: 29129568 DOI: 10.1016/j.ijmm.2017.11.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 10/30/2017] [Accepted: 11/05/2017] [Indexed: 12/12/2022] Open
Abstract
Leishmaniasis is transmitted by sand flies leading to parasite inoculation into skin. In the mammalian host, the parasite primarily resides in skin macrophages (MΦ) and dendritic cells (DC). MΦ are silently invaded by the parasite eliciting a stress response, whereas DC become activated, release IL-12, and prime antigen-specific T cells. Here we review the basics of the immune response against this human pathogen and elucidate the role and function DC and MΦ for establishment of protective immunity against leishmaniasis. We focus on cell type-specific differences in parasite uptake, phagocyte activation and processing of parasite antigens to facilitate an understanding how their respective function may be modulated e.g. under therapeutic considerations.
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Affiliation(s)
| | - Stefan Tenzer
- Institute for Immunology, University Medical Center, Johannes Gutenberg-University Mainz, Mainz, Germany
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21
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Faridgohar M, Nikoueinejad H. New findings of Toll-like receptors involved in Mycobacterium tuberculosis infection. Pathog Glob Health 2017; 111:256-264. [PMID: 28715935 DOI: 10.1080/20477724.2017.1351080] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Tuberculosis (TB), an important issue in the present age, affects millions of people each year. The infectious agent of TB, Mycobacterium tuberculosis (Mtb), interacts with the immune system which prevents the development of this bacterium as much as possible. In fact, the receptors on the surface of immune cells identify the bacteria, one of which is Toll-like receptors (TLRs). Different TLRs including 2, 4, 9 and 8 play critical roles in tuberculosis infection. In this paper, we focused on the role of TLRs which interact with different components of Mtb and, consequently, prevent the entrance and influence of bacteria on the body.
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Affiliation(s)
- Majid Faridgohar
- a Molecular Biology Research Center , Baqiyatallah University of Medical Sciences , Tehran , Iran
| | - Hassan Nikoueinejad
- b Nephrology and Urology Research Center , Baqiyatallah University of Medical Sciences , Tehran , Iran
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22
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Scott EA, Karabin NB, Augsornworawat P. Overcoming Immune Dysregulation with Immunoengineered Nanobiomaterials. Annu Rev Biomed Eng 2017; 19:57-84. [PMID: 28226216 DOI: 10.1146/annurev-bioeng-071516-044603] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The immune system is governed by an immensely complex network of cells and both intracellular and extracellular molecular factors. It must respond to an ever-growing number of biochemical and biophysical inputs by eliciting appropriate and specific responses in order to maintain homeostasis. But as with any complex system, a plethora of false positives and false negatives can occur to generate dysregulated responses. Dysregulated immune responses are essential components of diverse inflammation-driven pathologies, including cancer, heart disease, and autoimmune disorders. Nanoscale biomaterials (i.e., nanobiomaterials) have emerged as highly customizable platforms that can be engineered to interact with and direct immune responses, holding potential for the design of novel and targeted approaches to redirect or inhibit inflammation. Here, we present recent developments of nanobiomaterials that were rationally designed to target and modulate inflammatory cells and biochemical pathways for the treatment of immune dysregulation.
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Affiliation(s)
- Evan A Scott
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois 60208
| | - Nicholas B Karabin
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois 60208
| | - Punn Augsornworawat
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois 60208
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23
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Schaedler E, Remy-Ziller C, Hortelano J, Kehrer N, Claudepierre MC, Gatard T, Jakobs C, Préville X, Carpentier AF, Rittner K. Sequential administration of a MVA-based MUC1 cancer vaccine and the TLR9 ligand Litenimod (Li28) improves local immune defense against tumors. Vaccine 2016; 35:577-585. [PMID: 28012777 DOI: 10.1016/j.vaccine.2016.12.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 11/10/2016] [Accepted: 12/09/2016] [Indexed: 11/30/2022]
Abstract
TG4010 is an immunotherapeutic vaccine based on Modified Vaccinia virus Ankara (MVA) encoding the human tumor-associated antigen MUC1 and human IL-2. In combination with first-line standard of care chemotherapy in advanced metastatic non-small-cell lung cancer (NSCLC), repeated subcutaneous injection of TG4010 improved progression-free survival in phase 2b clinical trials. In preclinical tumor models, MVATG9931, the research version of TG4010, conferred antigen-specific responses against the weak antigen human MUC1. The combination of a suboptimal dose of MVATG9931 and the type B TLR9 ligand Litenimod (Li28) markedly increased survival in a subcutaneous RMA-MUC1 tumor model compared to the treatment with MVATG9931 or Li28 alone. The requirements for this protection were (i) de novo synthesis of MUC1, (ii) Li28 delivered several hours after MVATG9931 at the same site, (iii) at least two vaccination cycles, and (iv) implantation of MUC1-positive tumor cells in the vicinity to the vaccination site. Subcutaneously injected MVATG9931 allowed transient local gene expression and induced the local accumulation of MCP-1, RANTES, M-CSF, IL-15/IL-15R and IP-10. After repeated injection, CD4+ and CD8+ T lymphocytes, B lymphocytes, NK cells, pDCs, neutrophils, and macrophages accumulated around the injection site, local RANTES levels remained high. Delayed injection of Li28 into this environment, led to further accumulation of macrophages, the secretion of IL-18 and IL-1 beta, and an increase of the percentage of activated CD69+ NK cell. Combination treatment augmented the number of activated CD86+ DCs in the draining lymph nodes and increased the percentage of KLRG1+ CD127-CD8+ T cells at the injection site. In vivo depletion of macrophages around the injection site by Clodronate liposomes reduced local IL-18 levels and diminished survival rates significantly. Thus, sequential administration of MVATG9931 and Li28 improves local innate and adaptive immune defense against tumors, arguing for intratumoral delivery of this peculiar sequential combination therapy.
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Affiliation(s)
- Emmanuelle Schaedler
- TRANSGENE S.A., 400 Boulevard Gonthier d'Andernach, Parc d'Innovation, 67405 Illkirch-Graffenstaden, France
| | - Christelle Remy-Ziller
- TRANSGENE S.A., 400 Boulevard Gonthier d'Andernach, Parc d'Innovation, 67405 Illkirch-Graffenstaden, France
| | - Julie Hortelano
- TRANSGENE S.A., 400 Boulevard Gonthier d'Andernach, Parc d'Innovation, 67405 Illkirch-Graffenstaden, France
| | - Nadine Kehrer
- TRANSGENE S.A., 400 Boulevard Gonthier d'Andernach, Parc d'Innovation, 67405 Illkirch-Graffenstaden, France
| | | | - Tanja Gatard
- TRANSGENE S.A., 400 Boulevard Gonthier d'Andernach, Parc d'Innovation, 67405 Illkirch-Graffenstaden, France
| | - Christopher Jakobs
- Institut of Molecular Medicine, University of Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany
| | - Xavier Préville
- TRANSGENE S.A., 400 Boulevard Gonthier d'Andernach, Parc d'Innovation, 67405 Illkirch-Graffenstaden, France
| | - Antoine F Carpentier
- Laboratoire de Recherches Biochirurgicales, Université Paris Descartes, Hôpital Européen Georges Pompidou, 20 rue Leblanc, 75015 Paris, France
| | - Karola Rittner
- TRANSGENE S.A., 400 Boulevard Gonthier d'Andernach, Parc d'Innovation, 67405 Illkirch-Graffenstaden, France.
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Allen S, Liu YG, Scott E. Engineering nanomaterials to address cell-mediated inflammation in atherosclerosis. REGENERATIVE ENGINEERING AND TRANSLATIONAL MEDICINE 2016; 2:37-50. [PMID: 27135051 DOI: 10.1007/s40883-016-0012-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Atherosclerosis is an inflammatory disorder with a pathophysiology driven by both innate and adaptive immunity and a primary cause of cardiovascular disease (CVD) worldwide. Vascular inflammation and accumulation of foam cells and their products induce maturation of atheromas, or plaques, which can rupture by metalloprotease action, leading to ischemic stroke or myocardial infarction. Diverse immune cell populations participate in all stages of plaque maturation, many of which directly influence plaque stability and rupture via inflammatory mechanisms. Current clinical treatments for atherosclerosis focus on lowering serum levels of low-density lipoprotein (LDL) using therapeutics such as statins, administration of antithrombotic drugs, and surgical intervention. Strategies that address cell-mediated inflammation are lacking, and consequently have recently become an area of considerable research focus. Nanomaterials have emerged as highly advantageous tools for these studies, as they can be engineered to target specific inflammatory cell populations, deliver therapeutics of wide-ranging solubilities and enhance analytical methods that include imaging and proteomics. Furthermore, the highly phagocytic nature of antigen presenting cells (APCs), a diverse cell population central to the initiation of immune responses and inflammation, make them particularly amenable to targeting and modulation by nanoscale particulates. Nanomaterials have therefore become essential components of vaccine formulations and treatments for inflammation-driven pathologies like autoimmunity, and present novel opportunities for immunotherapeutic treatments of CVD. Here, we review recent progress in the design and use of nanomaterials for therapeutic assessment and treatment of atherosclerosis. We will focus on promising new approaches that utilize nanomaterials for cell-specific imaging, gene therapy and immunomodulation.
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Affiliation(s)
- Sean Allen
- Department of Biomedical Engineering, Northwestern University, Evanston IL, USA
| | - Yu-Gang Liu
- Department of Biomedical Engineering, Northwestern University, Evanston IL, USA
| | - Evan Scott
- Department of Biomedical Engineering, Northwestern University, Evanston IL, USA
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Nishimoto S, Fukuda D, Higashikuni Y, Tanaka K, Hirata Y, Murata C, Kim-Kaneyama JR, Sato F, Bando M, Yagi S, Soeki T, Hayashi T, Imoto I, Sakaue H, Shimabukuro M, Sata M. Obesity-induced DNA released from adipocytes stimulates chronic adipose tissue inflammation and insulin resistance. SCIENCE ADVANCES 2016; 2:e1501332. [PMID: 27051864 PMCID: PMC4820373 DOI: 10.1126/sciadv.1501332] [Citation(s) in RCA: 167] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 02/11/2016] [Indexed: 05/08/2023]
Abstract
Obesity stimulates chronic inflammation in adipose tissue, which is associated with insulin resistance, although the underlying mechanism remains largely unknown. Here we showed that obesity-related adipocyte degeneration causes release of cell-free DNA (cfDNA), which promotes macrophage accumulation in adipose tissue via Toll-like receptor 9 (TLR9), originally known as a sensor of exogenous DNA fragments. Fat-fed obese wild-type mice showed increased release of cfDNA, as determined by the concentrations of single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA) in plasma. cfDNA released from degenerated adipocytes promoted monocyte chemoattractant protein-1 (MCP-1) expression in wild-type macrophages, but not in TLR9-deficient (Tlr9 (-/-) ) macrophages. Fat-fed Tlr9 (-/-) mice demonstrated reduced macrophage accumulation and inflammation in adipose tissue and better insulin sensitivity compared with wild-type mice, whereas bone marrow reconstitution with wild-type bone marrow restored the attenuation of insulin resistance observed in fat-fed Tlr9 (-/-) mice. Administration of a TLR9 inhibitory oligonucleotide to fat-fed wild-type mice reduced the accumulation of macrophages in adipose tissue and improved insulin resistance. Furthermore, in humans, plasma ssDNA level was significantly higher in patients with computed tomography-determined visceral obesity and was associated with homeostasis model assessment of insulin resistance (HOMA-IR), which is the index of insulin resistance. Our study may provide a novel mechanism for the development of sterile inflammation in adipose tissue and a potential therapeutic target for insulin resistance.
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Affiliation(s)
- Sachiko Nishimoto
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8503, Japan
| | - Daiju Fukuda
- Department of Cardiovascular Medicine, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8503, Japan
- Corresponding author. E-mail: (D.F.); (M.S.)
| | - Yasutomi Higashikuni
- Department of Cardiovascular Medicine, The University of Tokyo, Tokyo 113-8655, Japan
| | - Kimie Tanaka
- Division for Health Service Promotion, The University of Tokyo, Tokyo 113-8655, Japan
| | - Yoichiro Hirata
- Department of Pediatrics, The University of Tokyo Hospital, Tokyo 113-8655, Japan
| | - Chie Murata
- Department of Human Genetics, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8503, Japan
| | - Joo-ri Kim-Kaneyama
- Department of Biochemistry, Showa University School of Medicine, Tokyo 142-8555, Japan
| | - Fukiko Sato
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8503, Japan
| | - Masahiro Bando
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8503, Japan
| | - Shusuke Yagi
- Department of Cardiovascular Medicine, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8503, Japan
| | - Takeshi Soeki
- Department of Cardiovascular Medicine, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8503, Japan
| | - Tetsuya Hayashi
- Laboratory of Cardiovascular Pharmacotherapy and Toxicology, Osaka University of Pharmaceutical Sciences, Osaka 569-1094, Japan
| | - Issei Imoto
- Department of Human Genetics, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8503, Japan
| | - Hiroshi Sakaue
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8503, Japan
| | - Michio Shimabukuro
- Department of Cardio-Diabetes Medicine, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8503, Japan
- Diabetes and Lifestyle-Related Disease Center, Tomishiro Central Hospital, Okinawa 901-0243, Japan
| | - Masataka Sata
- Department of Cardiovascular Medicine, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8503, Japan
- Corresponding author. E-mail: (D.F.); (M.S.)
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Toll-like receptor 9 signaling in dendritic cells regulates neutrophil recruitment to inflammatory foci following Leishmania infantum infection. Infect Immun 2015; 83:4604-16. [PMID: 26371124 DOI: 10.1128/iai.00975-15] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 09/06/2015] [Indexed: 11/20/2022] Open
Abstract
Leishmania infantum is a protozoan parasite that causes visceral leishmaniasis (VL). This infection triggers dendritic cell (DC) activation through the recognition of microbial products by Toll-like receptors (TLRs). Among the TLRs, TLR9 is required for DC activation by different Leishmania species. We demonstrated that TLR9 is upregulated in vitro and in vivo during infection. We show that C57BL/6 mice deficient in TLR9 expression (TLR9(-/-) mice) are more susceptible to infection and display higher parasite numbers in the spleen and liver. The increased susceptibility of TLR9(-/-) mice was due to the impaired recruitment of neutrophils to the infection foci associated with reduced levels of neutrophil chemoattractants released by DCs in the target organs. Moreover, both Th1 and Th17 cells were also committed in TLR9(-/-) mice. TLR9-dependent neutrophil recruitment is mediated via the MyD88 signaling pathway but is TIR domain-containing adapter-inducing interferon beta (TRIF) independent. Furthermore, L. infantum failed to activate both plasmacytoid and myeloid DCs from TLR9(-/-) mice, which presented reduced surface costimulatory molecule expression and chemokine release. Interestingly, neutrophil chemotaxis was affected both in vitro and in vivo when DCs were derived from TLR9(-/-) mice. Our results suggest that TLR9 plays a critical role in neutrophil recruitment during the protective response against L. infantum infection that could be associated with DC activation.
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Julian MW, Strange HR, Ballinger MN, Hotchkiss RS, Papenfuss TL, Crouser ED. Tolerance and Cross-Tolerance following Toll-Like Receptor (TLR)-4 and -9 Activation Are Mediated by IRAK-M and Modulated by IL-7 in Murine Splenocytes. PLoS One 2015. [PMID: 26218271 PMCID: PMC4517781 DOI: 10.1371/journal.pone.0132921] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Objective Immune suppression during critical illness predisposes to serious infections. We sought to determine the mechanisms regulating tolerance and cross-tolerance to common pro-inflammatory danger signals in a model that recapitulates the intact in vivo immune response. Materials and Methods Flt3-expanded splenocytes obtained from wild-type or matching IRAK-M knockout (IRAK-M-/-), C57BL/6, male mice (8–10 weeks old) were treated repeatedly or alternately with either LPS or CpGA DNA, agonists of Toll-like receptor (TLR)-4 and -9, respectively, over successive 24-hour periods. Supernatants were collected following each 24-hour period with cytokine release (ELISA) and splenocyte IRAK-M expression (Western blot) determined. Tolerance and cross-tolerance were assessed in the absence or presence of programmed death receptor (PD)-1 blocking antibody or IL-7 pre-treatment. Main Results Splenocytes notably exhibited both tolerance and cross-tolerance to subsequent treatments with either LPS or CpGA DNA. The character of tolerance and cross-tolerance in this model was distinct following initial LPS or CpGA treatment in that TNFα and IFNγ release (not IL-10) were suppressed following LPS; whereas, initial CpGA treatment suppressed TNFα, IFNγ and IL-10 release in response to subsequent stimulation (LPS or CpGA). Tolerance and cross-tolerance were unrelated to IL-10 release or PD-1 but were attenuated in IRAK-M-/- splenocytes. IL-7 significantly suppressed IRAK-M expression and restored TNFα and IFNγ production without influencing IL-10 release. Conclusions In summary, acute immune tolerance and cross-tolerance in response to LPS or CpGA were distinct in that LPS selectively suppressed pro-inflammatory cytokine responses; whereas, CpGA suppressed both pro- and anti-inflammatory responses. The induction of tolerance and cross-tolerance in response to common danger signals was mechanistically unrelated to IL-10 or PD-1 but was directly influenced by IRAK-M expression. IL-7 reduced IRAK-M expression and attenuated immune tolerance induced by either LPS or CpGA, and thus may be useful for reversal of immune tolerance in the setting of critical illness.
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Affiliation(s)
- Mark W. Julian
- Dorothy M. Davis Heart and Lung Research Institute, Division of Pulmonary Allergy, Critical Care, and Sleep Medicine, Wexner Medical Center, Columbus, OH, United States of America
| | - Heather R. Strange
- College of Veterinary Medicine, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH, United States of America
| | - Megan N. Ballinger
- Dorothy M. Davis Heart and Lung Research Institute, Division of Pulmonary Allergy, Critical Care, and Sleep Medicine, Wexner Medical Center, Columbus, OH, United States of America
| | - Richard S. Hotchkiss
- Departments of Anesthesiology, Medicine and Surgery, Washington University School of Medicine, St. Louis, MO, United States of America
| | - Tracey L. Papenfuss
- College of Veterinary Medicine, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH, United States of America
| | - Elliott D. Crouser
- Dorothy M. Davis Heart and Lung Research Institute, Division of Pulmonary Allergy, Critical Care, and Sleep Medicine, Wexner Medical Center, Columbus, OH, United States of America
- * E-mail:
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Ashok D, Acha-Orbea H. Timing is everything: dendritic cell subsets in murine Leishmania infection. Trends Parasitol 2014; 30:499-507. [DOI: 10.1016/j.pt.2014.08.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 08/07/2014] [Accepted: 08/08/2014] [Indexed: 02/02/2023]
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Bharti D, Kumar A, Mahla RS, Kumar S, Ingle H, Shankar H, Joshi B, Raut AA, Kumar H. The role of TLR9 polymorphism in susceptibility to pulmonary tuberculosis. Immunogenetics 2014; 66:675-81. [PMID: 25248338 DOI: 10.1007/s00251-014-0806-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 09/09/2014] [Indexed: 12/20/2022]
Abstract
Mycobacterium tuberculosis (MTB) is the causative agent of pulmonary tuberculosis (PTB), a major health problem that leads to 1.5 million deaths annually. Host genetic factors play a significant role in disease resistance/susceptibility by altering immunity against MTB. Toll-like receptor (TLR) sensors such as TLR2, TLR4, TLR8, and TLR9 are known to play a pivotal role in PTB via modulating sensor expression and/or effector responses. Single-nucleotide polymorphism (SNP) rs187084 (T-1486C) of the TLR9 promoter is associated with various autoimmune disorders and cancers. A recent bioinformatic analysis predicted that the T-1486C SNP is involved in PTB, although its potential role is unclear. To investigate the role of T-1486C in PTB, we stimulated PBMCs with the H37Rv whole cell lysate. We found that the presence of the "C" allele increases the transcriptional activity of the TLR9, which in turn induces high levels of Interferon gamma-induced protein 10 (IP-10), a biomarker for PTB. However, the expression of protective cytokines such as IFNγ and TNFα was observed significantly less with "C" allele in comparison to "T" allele. We further selected three different tribe populations showing differential susceptibility to PTB and performed genotypic analyses for the TLR9 promoter. We found a significantly lower minor allele frequency (MAF) of T-1486C in the Baiga tribe, wherein fewer PTB cases were reported, than that in the Gond and Korku tribes. Collectively, these data suggest that the minor "C" allele at rs187084 locus may be associated with susceptibility to PTB, which may explain the relatively lower PTB rates observed in Baiga tribe members.
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Affiliation(s)
- Deepak Bharti
- Laboratory of Immunology, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER), Indore-Bypass Road, Bhauri, Bhopal, 460023, Madhya Pradesh, India
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30
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Reid E, Charleston B. Type I and III interferon production in response to RNA viruses. J Interferon Cytokine Res 2014; 34:649-58. [PMID: 24956361 DOI: 10.1089/jir.2014.0066] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The biology of RNA viruses is closely linked to the type I and type III interferon (IFN) response of the host. These viruses display a range of molecular patterns that may be detected by host cells resulting in the induction of IFNs. Consequently, there are many examples of mechanisms employed by RNA viruses to block or delay IFN induction and reduce the expression of IFN-stimulated genes (ISGs), a necessary step in the virus lifecycle because of the capacity of IFNs to block virus replication. Efficient transmission of viruses depends, in part, on maintaining a balance between virus replication and host survival; specialized host cells, such as plasmacytoid dendritic cells, can sense viral molecular patterns and produce IFNs to help maintain this balance. There are now many examples of RNA viruses inducing type I and type III IFNs, and although these IFNs act through different receptors, in many systems studied, they induce a similar spectrum of genes. However, there may be a difference in the temporal expression pattern, with more prolonged expression of ISGs in response to type III IFN compared with type I IFN. There are also examples of synergy between type I and type III IFNs to induce antiviral responses. Clearly, it is important to understand the different roles of these IFNs in the antiviral response in vivo. One of the most striking differences between these 2 IFN systems is the distribution of the receptors: type I IFN receptors are expressed on most cells, yet type III receptor expression is restricted primarily to epithelial cells but has also been demonstrated on other cells, including dendritic cells. There is increasing evidence that type III IFNs are a key control mechanism against RNA viruses that infect respiratory and enteric epithelia.
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Affiliation(s)
- Elizabeth Reid
- Viral Immunology, The Pirbright Institute , Surrey, United Kingdom
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31
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Shodell M, Kempin S, Siegal FP. Plasmacytoid dendritic cell and CD4 + T cell deficiencies in untreated Hodgkin disease: implications for susceptibility to opportunistic infections. Leuk Lymphoma 2014; 55:2656-7. [DOI: 10.3109/10428194.2014.893312] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Michael Shodell
- Department of Biology, Long Island University,
C. W. Post Campus, Brookville, NY, USA
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Yeast virus-derived stimulator of the innate immune system augments the efficacy of virus vector-based immunotherapy. J Virol 2014; 88:5242-55. [PMID: 24574403 DOI: 10.1128/jvi.03819-13] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
UNLABELLED To identify novel stimulators of the innate immune system, we constructed a panel of eight HEK293 cell lines double positive for human Toll-like receptors (TLRs) and an NF-κB-inducible reporter gene. Screening of a large variety of compounds and cellular extracts detected a TLR3-activating compound in a microsomal yeast extract. Fractionation of this extract identified an RNA molecule of 4.6 kb, named nucleic acid band 2 (NAB2), that was sufficient to confer the activation of TLR3. Digests with single- and double-strand-specific RNases showed the double-strand nature of this RNA, and its sequence was found to be identical to that of the genome of the double-stranded RNA (dsRNA) L-BC virus of Saccharomyces cerevisiae. A large-scale process of production and purification of this RNA was established on the basis of chemical cell lysis and dsRNA-specific chromatography. NAB2 complexed with the cationic lipid Lipofectin but neither NAB2 nor Lipofectin alone induced the secretion of interleukin-12(p70) [IL-12(p70)], alpha interferon, gamma interferon-induced protein 10, macrophage inflammatory protein 1β, or IL-6 in human monocyte-derived dendritic cells. While NAB2 activated TLR3, Lipofectin-stabilized NAB2 also signaled via the cytoplasmic sensor for RNA recognition MDA-5. A significant increase of RMA-MUC1 tumor rejection and survival was observed in C57BL/6 mice after prophylactic vaccination with MUC1-encoding modified vaccinia virus Ankara (MVA) and NAB2-Lipofectin. This combination of immunotherapies strongly increased at the injection sites the percentage of infiltrating natural killer (NK) cells and plasmacytoid dendritic cells (pDCs), cell types which can modulate innate and adaptive immune responses. IMPORTANCE Virus-based cancer vaccines offer a good alternative to the treatment of cancer but could be improved. Starting from a screening approach, we have identified and characterized an unexplored biological molecule with immunomodulatory characteristics which augments the efficacy of an MVA-based immunotherapeutic agent. The immune modulator consists of the purified dsRNA genome isolated from a commercially used yeast strain, NAB2, mixed with a cationic lipid, Lipofectin. NAB2-Lipofectin stimulates the immune system via TLR3 and MDA-5. When it was injected at the MVA vaccination site, the immune modulator increased survival in a preclinical tumor model. We could demonstrate that NAB2-Lipofectin augments the MVA-induced infiltration of natural killer and plasmacytoid dendritic cells. We suggest indirect mechanisms of activation of these cell types by the influence of NAB2-Lipofectin on innate and adaptive immunity. Detailed analysis of cell migration at the vaccine injection site and the appropriate choice of an immune modulator should be considered to achieve the rational improvement of virus vector-based vaccination by immune modulators.
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Small molecule Me6TREN mobilizes hematopoietic stem/progenitor cells by activating MMP-9 expression and disrupting SDF-1/CXCR4 axis. Blood 2014; 123:428-41. [DOI: 10.1182/blood-2013-04-498535] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Key Points
The small molecule Me6TREN is a new potent and efficacious mobilizing agent of HSPCs and works more effectively than G-CSF or AMD3100. Me6 mobilizes murine HSPCs and functions by upregulating MMP-9 expression and disrupting the SDF-1α/CXCR4 axis.
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Natural killer cell-dependent anti-fibrotic pathway in liver injury via Toll-like receptor-9. PLoS One 2013; 8:e82571. [PMID: 24340043 PMCID: PMC3858328 DOI: 10.1371/journal.pone.0082571] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 10/24/2013] [Indexed: 01/07/2023] Open
Abstract
The toll-like receptor-9 (TLR9) agonist cytosine phosphate guanine (CpG), activates hepatic stellate cells (HSCs) and mediates fibrosis. We investigated the TLR9 effects on lymphocyte/HSCs interactions. Liver fibrosis was induced in wild-type (WT) mice by intra-peritoneal carbon-tetrachloride (CCl4) induction for 6 weeks. Fibrotic groups were intravenously treated by a vehicle versus CpG along last 2 weeks. Compared to vehicle-treated fibrotic WT, the in-vivo CpG-treatment significantly attenuated hepatic fibrosis and inflammation, associated with decreased CD8 and increased NK liver cells. In-vitro, co-cultures with vehicle-treated fibrotic NK cells increased HSCs proliferation (P<0.001) while their CpG-treated counterparts achieved a significant decrease. To investigate the role of lymphocytes, TLR9-/- mice induced-hepatic fibrosis were used. Although TLR9-/- mice manifested lower fibrotic profile as compared to their wild-type (WT) counterparts, senescence (SA-β-Gal activity) in the liver and ALT serum levels were significantly greater. In an adoptive transfer model; irradiated WT and TLR9-/- recipients were reconstituted with naïve WT or TLR9-/- lymphocytes. The adoptive transfer of TLR9-/- versus WT lymphocytes led to increased fibrosis of WT recipients. TLR9-/- fibrotic recipients reconstituted with TLR9-/- or WT lymphocytes showed no changes in hepatic fibrosis severity or ALT serum levels. TLR9 activation had inconsistent effects on lymphocytes and HSCs. The net balance of TLR9 activation in WT, displayed significant anti-fibrotic activity, accompanied by CD8 suppression and increased NK-cells, activity and adherence to HSCs. The pro-fibrotic and pro-inflammatory properties of TLR9-/- lymphocytes fail to activate HSCs with an early senescence in TLR9-/- mice.
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Dendritic cell subtypes from lymph nodes and blood show contrasted gene expression programs upon Bluetongue virus infection. J Virol 2013; 87:9333-43. [PMID: 23785206 DOI: 10.1128/jvi.00631-13] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Human and animal hemorrhagic viruses initially target dendritic cells (DCs). It has been proposed, but not documented, that both plasmacytoid DCs (pDCs) and conventional DCs (cDCs) may participate in the cytokine storm encountered in these infections. In order to evaluate the contribution of DCs in hemorrhagic virus pathogenesis, we performed a genome-wide expression analysis during infection by Bluetongue virus (BTV), a double-stranded RNA virus that induces hemorrhagic fever in sheep and initially infects cDCs. Both pDCs and cDCs accumulated in regional lymph nodes and spleen during BTV infection. The gene response profiles were performed at the onset of the disease and markedly differed with the DC subtypes and their lymphoid organ location. An integrative knowledge-based analysis revealed that blood pDCs displayed a gene signature related to activation of systemic inflammation and permeability of vasculature. In contrast, the gene profile of pDCs and cDCs in lymph nodes was oriented to inhibition of inflammation, whereas spleen cDCs did not show a clear functional orientation. These analyses indicate that tissue location and DC subtype affect the functional gene expression program induced by BTV and suggest the involvement of blood pDCs in the inflammation and plasma leakage/hemorrhage during BTV infection in the real natural host of the virus. These findings open the avenue to target DCs for therapeutic interventions in viral hemorrhagic diseases.
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Role of Toll-like receptor 9 signaling in experimental Leishmania braziliensis infection. Infect Immun 2013; 81:1575-84. [PMID: 23439309 DOI: 10.1128/iai.01401-12] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Infection with Leishmania braziliensis causes cutaneous or mucocutaneous leishmaniasis in humans. Toll-like receptor 9 (TLR9) expression has been found in granulomas of lesions in L. braziliensis-infected individuals. L. braziliensis inoculation in mice induces very small lesions that are self-healing, whereas deficiency in the TLR adaptor molecule, MyD88, renders mice susceptible to infection. The TLR involved has not been identified, prompting us to investigate if TLR9 triggering by the parasite contributes to the strong resistance to infection observed in L. braziliensis-inoculated mice. The parasites activated wild-type (WT) dendritic cells (DCs) in vitro but not DCs derived from TLR9(-/-) mice. TLR9(-/-) mice inoculated with L. braziliensis exhibited a transient susceptibility characterized by increased lesion size and parasite burden compared to those of WT mice. Surprisingly, elevated levels of gamma interferon (IFN-γ) were measured at the site of infection and in draining lymph node T cells of TLR9(-/-) mice at the peak of susceptibility, suggesting that unlike observations in vitro, the parasite could induce DC activation leading to the development of Th1 cells in the absence of TLR9 expression. Taken together, these data show that TLR9 signaling is important for the early control of lesion development and parasite burden but is dispensable for the differentiation of Th1 cells secreting IFN-γ, and the high levels of this cytokine are not sufficient to control early parasite replication following L. braziliensis infection.
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Pathogen sensors and chemokine receptors in dendritic cell subsets. Vaccine 2012; 30:7652-7. [PMID: 23142133 DOI: 10.1016/j.vaccine.2012.10.043] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Accepted: 10/12/2012] [Indexed: 02/07/2023]
Abstract
Pathogen sensors such as Toll-like receptors (TLRs) detect microorganism- or host-derived conserved molecular structures, including lipids or nucleic acids and provoke activation of Ag presenting cells such as dendritic cells (DCs). Several synthetic TLR ligands, especially oligonucleotides, are being developed as promising vaccines for infectious diseases, cancers or allergies. DCs are heterogeneous and consist of various subsets, each of which expresses a subset-specific repertoire of TLRs and responds to the TLR signaling in a subset-specific manner. Furthermore, each DC subset expresses a set of chemokine receptors that regulate its function and behavior. Here I review the functions of two DC subsets and how chemokine receptors function in these subsets. One is the plasmacytoid DC (pDC), which expresses nucleic acid sensing receptors TLR7 and TLR9 and secretes large amounts of type I interferons in response to TLR7/9 signaling. The other is splenic CD8α(+) conventional DC (cDC). This DC subset expresses lipid sensors, TLR2 and TLR4, and nucleic acid sensors, TLR3, TLR9 and TLR13 and is specialized for antigen crosspresentation. Several chemokine receptors are differentially expressed on these DC subsets. The homologues of these murine DC subsets are also found in humans. Understanding how these DC subsets function and respond to TLR ligands and chemokines should be important for development of effective vaccines.
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Altered natural killer cells' response to herpes virus infection in multiple sclerosis involves KIR2DL2 expression. J Neuroimmunol 2012; 251:55-64. [PMID: 22871633 DOI: 10.1016/j.jneuroim.2012.07.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Revised: 06/25/2012] [Accepted: 07/17/2012] [Indexed: 01/05/2023]
Abstract
The role of herpes viruses as potential triggers of multiple sclerosis (MS) is still debated. Peripheral blood mononuclear cells from MS patients and controls were treated with CpG sequences and infected in vitro with HSV-1. Samples were analyzed for viral yield, TLR9 pathways, cytokine secretion, NK cell activation and killer immunoglobulin-like receptor (KIR) expression. CpG treatment promoted an unexpected sensitivity to herpes virus infection in a subset of MS patients: TLR9 pathways did not show defects while NK cells presented decreased degranulation and cytotoxicity and up-regulated the inhibitory KIR2DL2 receptor. CpG treatment of purified NK cells affected directly KIR2DL2 modulation and cell activation. These data suggest potential implications for viral pathogenesis of MS.
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