151
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Tartey S, Takeuchi O. Pathogen recognition and Toll-like receptor targeted therapeutics in innate immune cells. Int Rev Immunol 2017; 36:57-73. [PMID: 28060562 DOI: 10.1080/08830185.2016.1261318] [Citation(s) in RCA: 151] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The innate immune system deploys a variety of pattern-recognition receptors (PRRs) which include Toll-like receptors (TLRs), RIG-I-like receptors, NOD-like receptors, and C-type lectin receptors to detect the invasion of pathogens and initiate protective responses. The intercellular and intracellular orchestration of signals from different PRRs, their endogenous or microbial ligands and accessory molecules determine the stimulatory or inhibitory responses. Progressing over the last two decades, considerable research on the molecular mechanisms underlying host-pathogen interactions has led to a paradigm shift of our understanding of TLR signaling in the innate immune system. Given that a significant amount of evidence implicates TLRs in the pathogenesis of immune diseases and cancer, and their activation occurs early in the inflammatory cascade, they are attractive targets for novel therapeutic agents. In this review, we discuss the recent advances in TLR signaling cross talks and the mechanism of pathogen recognition with special emphasis on the role of TLRs in tumor immunity and TLR-targeted therapeutics.
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Affiliation(s)
- Sarang Tartey
- a Laboratory of Infection and Prevention, Institute for Virus Research, Kyoto University , Kawara-Cho, Sakyo-Ku, Kyoto , Japan.,b AMED-CREST, Japan Agency for Medical Research and Development , Kyoto , Japan
| | - Osamu Takeuchi
- a Laboratory of Infection and Prevention, Institute for Virus Research, Kyoto University , Kawara-Cho, Sakyo-Ku, Kyoto , Japan.,b AMED-CREST, Japan Agency for Medical Research and Development , Kyoto , Japan
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152
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Knowlton AA. Paying for the Tolls: The High Cost of the Innate Immune System for the Cardiac Myocyte. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1003:17-34. [PMID: 28667552 DOI: 10.1007/978-3-319-57613-8_2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The cardiac myocyte differs strikingly from the specialized cells of the immune system, which has two different responses to invading organisms and tissue damage. Adaptive or acquired immunity generates highly specific antibodies in response to threats and is an essential component of immunity; however, adaptive immunity can take 4-7 days to mobilize, and a more primitive response, innate immunity, fills the gap. Innate immunity is expressed in complex and in primitive life forms. Specialized receptors, Toll-like receptors (TLRs), which are widely distributed throughout different tissues recognize danger signals and rapidly respond with the release of noxious substances, such as TNFα. The problem is that many endogenous molecules have been found to act as ligands for specific TLRs, and when these molecules are released into the extracellular environment, they can cause problems by activating innate immunity and an inflammatory response. In cardiac myocytes heat shock protein (HSP)60 can activate TLR4, as can HMGB1, and this type of response can amplify the response to ischemia/reperfusion leading to increased cell and tissue injury. Activation of TLRs can potentially amplify chronic, inflammatory diseases, such as ischemic heart failure. Thus, it is important to understand the regulation of the TLRs and their downstream effects. This chapter will focus on the TLRs and cardiac myocytes.
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Affiliation(s)
- Anne A Knowlton
- Cardiovascular Division, Department of Medicine, Molecular and Cellular Cardiology, University of California, Davis, One Shields Avenue, Davis, CA, 95616, USA. .,Department of Pharmacology, University of California, Davis, CA, USA. .,The Department of Veteran's Affairs, Northern California VA, Sacramento, CA, USA.
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153
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Kovarik P, Castiglia V, Ivin M, Ebner F. Type I Interferons in Bacterial Infections: A Balancing Act. Front Immunol 2016; 7:652. [PMID: 28082986 PMCID: PMC5183637 DOI: 10.3389/fimmu.2016.00652] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 12/14/2016] [Indexed: 01/21/2023] Open
Abstract
Defense against bacterial infections requires activation of the immune response as well as timely reestablishment of tissue and immune homeostasis. Instauration of homeostasis is critical for tissue regeneration, wound healing, and host recovery. Recent studies revealed that severe infectious diseases frequently result from failures in homeostatic processes rather than from inefficient pathogen eradication. Type I interferons (IFN) appear to play a key role in such processes. Remarkably, the involvement of type I IFNs in the regulation of immune and tissue homeostasis upon bacterial insult may have beneficial or detrimental consequences for the host. The reasons for such ambivalent function of type I IFNs are not understood. The disparate effects of type I IFNs on bacterial infections are in marked contrast to their well-established protective roles in most viral infections. In this review, we will focus on type I IFN effector mechanisms which balance processes involved in immune and tissue homeostasis during specific bacterial infections and highlight the most important missing links in our understanding of type I IFN functions.
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Affiliation(s)
- Pavel Kovarik
- Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
| | | | - Masa Ivin
- Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
| | - Florian Ebner
- Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
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154
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Shirjang S, Mansoori B, Solali S, Hagh MF, Shamsasenjan K. Toll-like receptors as a key regulator of mesenchymal stem cell function: An up-to-date review. Cell Immunol 2016; 315:1-10. [PMID: 28284487 DOI: 10.1016/j.cellimm.2016.12.005] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Revised: 12/07/2016] [Accepted: 12/24/2016] [Indexed: 02/07/2023]
Abstract
Understanding the role of toll-like receptors (TLRs) in the immunomodulation potential, differentiation, migration, and survival of mesenchymal stem cells (MSCs) is absolutely vital to fully exploiting their MSC-based therapeutic potential. Furthermore, through recognition of exogenous or endogenous ligands produced upon injury, TLRs have been linked to allograft rejection and maintenance of chronic inflammatory diseases, including Crohn's disease, rheumatoid arthritis. Characterizing the effect of TLRs in biological control of MSCs fate and function could improve our knowledge about the MSC-based cell therapy and immunotherapy. In this paper, we outline the impacts of TLR activation and mechanisms on MSCs immunomodulatory functions, differentiation, migration, and survivability. Moreover, we indicate that the expression patterns of TLRs in MSCs from different sources.
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Affiliation(s)
- Solmaz Shirjang
- Hematology and Oncology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Behzad Mansoori
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Saeed Solali
- Hematology and Oncology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Karim Shamsasenjan
- Hematology and Oncology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
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155
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Majer O, Liu B, Barton GM. Nucleic acid-sensing TLRs: trafficking and regulation. Curr Opin Immunol 2016; 44:26-33. [PMID: 27907816 DOI: 10.1016/j.coi.2016.10.003] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 10/28/2016] [Indexed: 12/11/2022]
Abstract
Toll-like receptors (TLRs) play an important role in innate immune responses against pathogenic microorganisms or tissue damage. Nucleic acid (NA)-sensing TLRs localize in intracellular vesicular compartments and recognize foreign-derived and host-derived nucleic acid ligands. Inappropriate activation of NA-sensing TLRs can cause pathogenic inflammation and autoimmunity. Multiple regulatory mechanisms exist to limit recognition of self-NAs. This review summarizes recent progress that has been made in understanding how NA-sensing TLRs are regulated via trafficking, proteolytic cleavage, as well as ligand processing and recognition.
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Affiliation(s)
- Olivia Majer
- Division of Immunology & Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, United States
| | - Bo Liu
- Division of Immunology & Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, United States
| | - Gregory M Barton
- Division of Immunology & Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, United States
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156
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Athari SS, Athari SM, Beyzay F, Movassaghi M, Mortaz E, Taghavi M. Critical role of Toll-like receptors in pathophysiology of allergic asthma. Eur J Pharmacol 2016; 808:21-27. [PMID: 27894811 DOI: 10.1016/j.ejphar.2016.11.047] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Revised: 11/21/2016] [Accepted: 11/25/2016] [Indexed: 12/11/2022]
Abstract
Allergic asthma is an airway disease, characterized by reversible bronchoconstriction, chronic inflammation of the airway, and thickness of smooth muscle in the respiratory tract. Asthma is orchestrated by an excessive Th2-adaptive immune response, in which innate immunity plays a key role. Recently TLRs have received more and more attention as they are central to orchestrate the innate immune responses. TLRs are localized as integral membrane or intracellular glycoproteins with those on the cell surface sensing microbial antigens and the ones, localized in intracellular vesicles, sensing microbial nucleic acid species. Having recognized microbial antigens, TLRs conduct the immune response towards a pro- or anti-allergy response. As a double-edged sword, they could initiate either harmful or helpful responses by the immune system in case of allergic asthma. In the current review, we will describe the role of TLRs and their signaling pathways in allergic asthma.
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Affiliation(s)
- Seyyed Shamsadin Athari
- Research Center for Food Hygiene and Safety, Shahid Sadoughi University of Medical Sciences, Yazd, Iran; Health policy Research Center, Shiraz University of Medical Sciences, Shiraz, Iran; Department of Immunology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | | | - Fateme Beyzay
- Department of Immunology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Masoud Movassaghi
- Department of Pathology and Laboratory Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
| | - Esmaeil Mortaz
- Clinical Tuberculosis and Epidemiology Research Center, National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran; Department of Immunology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Mehdi Taghavi
- Mycology Research Center, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran
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157
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Kohailan M, Alanazi M, Rouabhia M, Alamri A, Parine NR, Alhadheq A, Basavarajappa S, Abdullah Al-Kheraif AA, Semlali A. Effect of smoking on the genetic makeup of toll-like receptors 2 and 6. Onco Targets Ther 2016; 9:7187-7198. [PMID: 27920557 PMCID: PMC5123654 DOI: 10.2147/ott.s109650] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Background Cigarette smoking is a major risk factor for lung cancer, asthma, and oral cancer, and is central to the altered innate immune responsiveness to infection. Many hypotheses have provided evidence that cigarette smoking induces more genetic changes in genes involved in the development of many cigarette-related diseases. This alteration may be from single-nucleotide polymorphisms (SNPs) in innate immunity genes, especially the toll-like receptors (TLRs). Objective In this study, the genotype frequencies of TLR2 and TLR6 in smoking and nonsmoking population were examined. Methods Saliva samples were collected from 177 smokers and 126 nonsmokers. The SNPs used were rs3804100 (1350 T/C, Ser450Ser) and rs3804099 (597 T/C, Asn199Asn) for TLR2 and rs3796508 (979 G/A, Val327Met) and rs5743810 (745 T/C, Ser249Pro) for TLR6. Results Results showed that TLR2 rs3804100 has a significant effect in short-term smokers (OR =2.63; P=0.04), and this effect is not observed in long-term smokers (>5 years of smoking). Therefore, this early mutation may be repaired by the DNA repair system. For TLR2 rs3804099, the variation in genotype frequencies between the smokers and control patients was due to a late mutation, and its protective role appears only in long-term smokers (OR =0.40, P=0.018). In TLR6 rs5743810, the TT genotype is significantly higher in smokers than in nonsmokers (OR =6.90). The effect of this SNP is observed in long-term smokers, regardless of the smoking regime per day. Conclusion TLR2 (rs3804100 and rs3804099) and TLR6 (rs5743810) can be used as a potential index in the diagnosis and prevention of more diseases caused by smoking.
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Affiliation(s)
- Muhammad Kohailan
- Genome Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Mohammad Alanazi
- Genome Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Mahmoud Rouabhia
- Département de Stomatologie, Faculté de Médecine Dentaire, Groupe de Recherche en Écologie Buccale, Université Laval, Québec City, QC, Canada
| | - Abdullah Alamri
- Genome Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Narasimha Reddy Parine
- Genome Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Abdullah Alhadheq
- Genome Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Santhosh Basavarajappa
- Dental Biomaterial Research Chair, Department of Dental Health, College of Applied Medical Sciences, King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Abdul Aziz Abdullah Al-Kheraif
- Dental Biomaterial Research Chair, Department of Dental Health, College of Applied Medical Sciences, King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Abdelhabib Semlali
- Genome Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, Kingdom of Saudi Arabia
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158
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Vabret N, Bhardwaj N, Greenbaum BD. Sequence-Specific Sensing of Nucleic Acids. Trends Immunol 2016; 38:53-65. [PMID: 27856145 DOI: 10.1016/j.it.2016.10.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 10/14/2016] [Accepted: 10/14/2016] [Indexed: 12/25/2022]
Abstract
Innate immune cells are endowed with many nucleic acid receptors, but the role of sequence in the detection of foreign organisms remains unclear. Can sequence patterns influence recognition? In addition, how can we infer those patterns from sequence data? Here, we detail recent computational and experimental evidence associated with sequence-specific sensing. We review the mechanisms underlying the detection and discrimination of foreign sequences from self. We also describe quantitative approaches used to infer the stimulatory capacity of a given pathogen nucleic acid species, and the influence of sequence-specific sensing on host-pathogen coevolution, including endogenous sequences of foreign origin. Finally, we speculate how further studies of sequence-specific sensing will be useful to improve vaccine design, gene therapy and cancer treatment.
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Affiliation(s)
- Nicolas Vabret
- Tisch Cancer Institute, Departments of Medicine, Hematology, and Medical Oncology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Departments of Oncological Sciences and Pathology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
| | - Nina Bhardwaj
- Tisch Cancer Institute, Departments of Medicine, Hematology, and Medical Oncology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Benjamin D Greenbaum
- Tisch Cancer Institute, Departments of Medicine, Hematology, and Medical Oncology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Departments of Oncological Sciences and Pathology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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159
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van de Beek D, Brouwer M, Hasbun R, Koedel U, Whitney CG, Wijdicks E. Community-acquired bacterial meningitis. Nat Rev Dis Primers 2016; 2:16074. [PMID: 27808261 DOI: 10.1038/nrdp.2016.74] [Citation(s) in RCA: 163] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Meningitis is an inflammation of the meninges and subarachnoid space that can also involve the brain cortex and parenchyma. It can be acquired spontaneously in the community - community-acquired bacterial meningitis - or in the hospital as a complication of invasive procedures or head trauma (nosocomial bacterial meningitis). Despite advances in treatment and vaccinations, community-acquired bacterial meningitis remains one of the most important infectious diseases worldwide. Streptococcus pneumoniae and Neisseria meningitidis are the most common causative bacteria and are associated with high mortality and morbidity; vaccines targeting these organisms, which have designs similar to the successful vaccine that targets Haemophilus influenzae type b meningitis, are now being used in many routine vaccination programmes. Experimental and genetic association studies have increased our knowledge about the pathogenesis of bacterial meningitis. Early antibiotic treatment improves the outcome, but the growing emergence of drug resistance as well as shifts in the distribution of serotypes and groups are fuelling further development of new vaccines and treatment strategies. Corticosteroids were found to be beneficial in high-income countries depending on the bacterial species. Further improvements in the outcome are likely to come from dampening the host inflammatory response and implementing preventive measures, especially the development of new vaccines.
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Affiliation(s)
- Diederik van de Beek
- Department of Neurology, Center of Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, P.O. BOX 22660, 1100DD Amsterdam, The Netherlands
| | - Matthijs Brouwer
- Department of Neurology, Center of Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, P.O. BOX 22660, 1100DD Amsterdam, The Netherlands
| | - Rodrigo Hasbun
- Department of Internal Medicine, UT Health McGovern Medical School, Houston, Texas, USA
| | - Uwe Koedel
- Department of Neurology, Clinic Grosshadern of the Ludwig-Maximilians University of Munich, Munich, Germany
| | - Cynthia G Whitney
- Respiratory Diseases Branch, Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Eelco Wijdicks
- Division of Critical Care Neurology, Department of Neurology, Mayo Clinic, Rochester, Minnesota, USA
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160
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Gao D, Li W. Structures and recognition modes of toll-like receptors. Proteins 2016; 85:3-9. [DOI: 10.1002/prot.25179] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 09/06/2016] [Accepted: 09/24/2016] [Indexed: 12/13/2022]
Affiliation(s)
- Dong Gao
- Shenzhen Hornetcorn Biotechnology Co, Ltd; Shenzhen 518045 China
| | - Wang Li
- Shenzhen Hornetcorn Biotechnology Co, Ltd; Shenzhen 518045 China
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161
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Bertheloot D, Naumovski AL, Langhoff P, Horvath GL, Jin T, Xiao TS, Garbi N, Agrawal S, Kolbeck R, Latz E. RAGE Enhances TLR Responses through Binding and Internalization of RNA. THE JOURNAL OF IMMUNOLOGY 2016; 197:4118-4126. [PMID: 27798148 DOI: 10.4049/jimmunol.1502169] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 09/20/2016] [Indexed: 01/08/2023]
Abstract
Nucleic acid recognition is an important mechanism that enables the innate immune system to detect microbial infection and tissue damage. To minimize the recognition of self-derived nucleic acids, all nucleic acid-sensing signaling receptors are sequestered away from the cell surface and are activated in the cytoplasm or in endosomes. Nucleic acid sensing in endosomes relies on members of the TLR family. The receptor for advanced glycation end-products (RAGE) was recently shown to bind DNA at the cell surface, facilitating DNA internalization and subsequent recognition by TLR9. In this article, we show that RAGE binds RNA molecules in a sequence-independent manner and enhances cellular RNA uptake into endosomes. Gain- and loss-of-function studies demonstrate that RAGE increases the sensitivity of all ssRNA-sensing TLRs (TLR7, TLR8, TLR13), suggesting that RAGE is an integral part of the endosomal nucleic acid-sensing system.
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Affiliation(s)
- Damien Bertheloot
- Institute of Innate Immunity, University Hospital, University of Bonn, 53127 Bonn, Germany
| | | | - Pia Langhoff
- Institute of Innate Immunity, University Hospital, University of Bonn, 53127 Bonn, Germany.,German Center for Neurodegenerative Diseases, 53117 Bonn, Germany
| | - Gabor L Horvath
- Institute of Innate Immunity, University Hospital, University of Bonn, 53127 Bonn, Germany
| | - Tengchuan Jin
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Tsan Sam Xiao
- Department of Pathology, Case Western Reserve University, Cleveland, OH 44106
| | - Natalio Garbi
- Institute of Molecular Medicine and Experimental Immunology, University of Bonn, 53127 Bonn, Germany
| | | | | | - Eicke Latz
- Institute of Innate Immunity, University Hospital, University of Bonn, 53127 Bonn, Germany; .,German Center for Neurodegenerative Diseases, 53117 Bonn, Germany.,Department of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01605
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162
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Zhang Z, Ohto U, Shibata T, Krayukhina E, Taoka M, Yamauchi Y, Tanji H, Isobe T, Uchiyama S, Miyake K, Shimizu T. Structural Analysis Reveals that Toll-like Receptor 7 Is a Dual Receptor for Guanosine and Single-Stranded RNA. Immunity 2016; 45:737-748. [DOI: 10.1016/j.immuni.2016.09.011] [Citation(s) in RCA: 232] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 06/13/2016] [Accepted: 06/30/2016] [Indexed: 11/26/2022]
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163
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Pelka K, Shibata T, Miyake K, Latz E. Nucleic acid-sensing TLRs and autoimmunity: novel insights from structural and cell biology. Immunol Rev 2016; 269:60-75. [PMID: 26683145 DOI: 10.1111/imr.12375] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Invasion of pathogenic microorganisms or tissue damage activates innate immune signaling receptors that sample subcellular locations for foreign molecular structures, altered host molecules, or signs of compartment breaches. Upon engagement of innate immune receptors an acute but transient inflammatory response is initiated, aimed at the clearance of pathogens and cellular debris. Among the molecules that are sensed are nucleic acids, which activate several members of the transmembrane Toll-like receptor (TLR) family. Inappropriate recognition of nucleic acids by TLRs can cause inflammatory pathologies and autoimmunity. Here, we review the mechanisms involved in triggering nucleic acid-sensing TLRs and indicate checkpoints that restrict their activation to endolysosomal compartments. These mechanisms are crucial to sample the content of endosomes for nucleic acids in the context of infection or tissue damage, yet prevent accidental activation by host nucleic acids under physiological conditions. Decoding the molecular mechanisms that regulate nucleic acid recognition by TLRs is central to understand pathologies linked to unrestricted nucleic acid sensing and to develop novel therapeutic strategies.
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Affiliation(s)
- Karin Pelka
- Institute of Innate Immunity, University Hospitals Bonn, Bonn, Germany
| | - Takuma Shibata
- Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, Tokyo, Japan.,Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo, Japan
| | - Kensuke Miyake
- Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Eicke Latz
- Institute of Innate Immunity, University Hospitals Bonn, Bonn, Germany.,German Center for Neurodegenerative Diseases, Bonn, Germany.,Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
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164
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Goulopoulou S, McCarthy CG, Webb RC. Toll-like Receptors in the Vascular System: Sensing the Dangers Within. Pharmacol Rev 2016; 68:142-67. [PMID: 26721702 DOI: 10.1124/pr.114.010090] [Citation(s) in RCA: 166] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Toll-like receptors (TLRs) are components of the innate immune system that respond to exogenous infectious ligands (pathogen-associated molecular patterns, PAMPs) and endogenous molecules that are released during host tissue injury/death (damage-associated molecular patterns, DAMPs). Interaction of TLRs with their ligands leads to activation of downstream signaling pathways that induce an immune response by producing inflammatory cytokines, type I interferons (IFN), and other inflammatory mediators. TLR activation affects vascular function and remodeling, and these molecular events prime antigen-specific adaptive immune responses. Despite the presence of TLRs in vascular cells, the exact mechanisms whereby TLR signaling affects the function of vascular tissues are largely unknown. Cardiovascular diseases are considered chronic inflammatory conditions, and accumulating data show that TLRs and the innate immune system play a determinant role in the initiation and development of cardiovascular diseases. This evidence unfolds a possibility that targeting TLRs and the innate immune system may be a novel therapeutic goal for these conditions. TLR inhibitors and agonists are already in clinical trials for inflammatory conditions such as asthma, cancer, and autoimmune diseases, but their study in the context of cardiovascular diseases is in its infancy. In this article, we review the current knowledge of TLR signaling in the cardiovascular system with an emphasis on atherosclerosis, hypertension, and cerebrovascular injury. Furthermore, we address the therapeutic potential of TLR as pharmacological targets in cardiovascular disease and consider intriguing research questions for future study.
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Affiliation(s)
- Styliani Goulopoulou
- Institute for Cardiovascular and Metabolic Diseases, Department of Obstetrics and Gynecology, University of North Texas Health Science Center, Fort Worth, Texas; and Department of Physiology, Augusta University, Augusta, Georgia
| | - Cameron G McCarthy
- Institute for Cardiovascular and Metabolic Diseases, Department of Obstetrics and Gynecology, University of North Texas Health Science Center, Fort Worth, Texas; and Department of Physiology, Augusta University, Augusta, Georgia
| | - R Clinton Webb
- Institute for Cardiovascular and Metabolic Diseases, Department of Obstetrics and Gynecology, University of North Texas Health Science Center, Fort Worth, Texas; and Department of Physiology, Augusta University, Augusta, Georgia
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165
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Wang Y, Bi X, Chu Q, Xu T. Discovery of toll-like receptor 13 exists in the teleost fish: Miiuy croaker (Perciformes, Sciaenidae). DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2016; 61:25-33. [PMID: 26952767 DOI: 10.1016/j.dci.2016.03.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 03/02/2016] [Accepted: 03/03/2016] [Indexed: 06/05/2023]
Abstract
Toll-like receptors (TLRs) play an indispensable role in the immune response for pathogen recognition and triggering not only innate immunity but also adaptive immunity. Here we report the TLR13 homologue, one member of TLRs, in Perciformes (especially Sciaenidae). And we used the miiuy croaker as represented species for further functional experiments. Former study reported the TLR13 only expressed in murine, and we are the first to report the teleost TLR13 (mmiTLR13). MmiTLR13 expressed highly in immune defense related tissues, such as the liver, spleen, and kidney, and Vibrio anguillarum or poly(I:C) infection showed the immune response of mmiTLR13. Further luciferase reporter assays showed the ability for activation of ISRE luciferase reporter, but it failed to active NF-κB. And further gene silence by short hairpin RNA (shRNA) confirmed the results. Immunofluorescence of mmiTLR13 presents the cytoplasmic distribution in Hela cell. In addition, the Toll/interleukin 1 receptor (TIR) domain of mammal TLR5 exhibits high identity with TLR13, which indicated the high homology between TLR5 and TLR13. These findings will lay the fundamental cornerstone for further research of teleost TLR13 and expand the horizon for better understand the teleost TLRs system.
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Affiliation(s)
- Yanjin Wang
- Laboratory of Fish Biogenetics & Immune Evolution, College of Marine Science, Zhejiang Ocean University, Zhoushan, 316022, China
| | - Xueyi Bi
- Laboratory of Fish Biogenetics & Immune Evolution, College of Marine Science, Zhejiang Ocean University, Zhoushan, 316022, China
| | - Qing Chu
- Laboratory of Fish Biogenetics & Immune Evolution, College of Marine Science, Zhejiang Ocean University, Zhoushan, 316022, China
| | - Tianjun Xu
- Laboratory of Fish Biogenetics & Immune Evolution, College of Marine Science, Zhejiang Ocean University, Zhoushan, 316022, China.
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166
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Fritz JV, Heintz-Buschart A, Ghosal A, Wampach L, Etheridge A, Galas D, Wilmes P. Sources and Functions of Extracellular Small RNAs in Human Circulation. Annu Rev Nutr 2016; 36:301-36. [PMID: 27215587 PMCID: PMC5479634 DOI: 10.1146/annurev-nutr-071715-050711] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Various biotypes of endogenous small RNAs (sRNAs) have been detected in human circulation, including microRNAs, transfer RNAs, ribosomal RNA, and yRNA fragments. These extracellular sRNAs (ex-sRNAs) are packaged and secreted by many different cell types. Ex-sRNAs exhibit differences in abundance in several disease states and have, therefore, been proposed for use as effective biomarkers. Furthermore, exosome-borne ex-sRNAs have been reported to elicit physiological responses in acceptor cells. Exogenous ex-sRNAs derived from diet (most prominently from plants) and microorganisms have also been reported in human blood. Essential issues that remain to be conclusively addressed concern the (a) presence and sources of exogenous ex-sRNAs in human bodily fluids, (b) detection and measurement of ex-sRNAs in human circulation, (c) selectivity of ex-sRNA export and import, (d) sensitivity and specificity of ex-sRNA delivery to cellular targets, and (e) cell-, tissue-, organ-, and organism-wide impacts of ex-sRNA-mediated cell-to-cell communication. We survey the present state of knowledge of most of these issues in this review.
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MESH Headings
- Animals
- Biological Transport
- Biomarkers/blood
- Cell Communication
- Diet
- Gastrointestinal Microbiome/immunology
- Gene Expression Regulation
- Host-Parasite Interactions
- Host-Pathogen Interactions
- Humans
- Immunity, Innate
- MicroRNAs/blood
- MicroRNAs/metabolism
- Models, Biological
- RNA, Bacterial/blood
- RNA, Bacterial/metabolism
- RNA, Plant/blood
- RNA, Plant/metabolism
- RNA, Ribosomal/blood
- RNA, Ribosomal/metabolism
- RNA, Small Interfering/blood
- RNA, Small Interfering/metabolism
- RNA, Small Untranslated/blood
- RNA, Small Untranslated/metabolism
- RNA, Transfer/blood
- RNA, Transfer/metabolism
- RNA, Viral/blood
- RNA, Viral/metabolism
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Affiliation(s)
- Joëlle V Fritz
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Campus Belval, L-4367 Belvaux, Luxembourg; ,
| | - Anna Heintz-Buschart
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Campus Belval, L-4367 Belvaux, Luxembourg; ,
| | - Anubrata Ghosal
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Linda Wampach
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Campus Belval, L-4367 Belvaux, Luxembourg; ,
| | - Alton Etheridge
- Pacific Northwest Diabetes Research Institute, Seattle, Washington 98122
| | - David Galas
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Campus Belval, L-4367 Belvaux, Luxembourg; ,
- Pacific Northwest Diabetes Research Institute, Seattle, Washington 98122
| | - Paul Wilmes
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Campus Belval, L-4367 Belvaux, Luxembourg; ,
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167
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Stein K, Brand S, Jenckel A, Sigmund A, Chen ZJ, Kirschning CJ, Kauth M, Heine H. Endosomal recognition of Lactococcus lactis G121 and its RNA by dendritic cells is key to its allergy-protective effects. J Allergy Clin Immunol 2016; 139:667-678.e5. [PMID: 27544739 DOI: 10.1016/j.jaci.2016.06.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 06/02/2016] [Accepted: 06/13/2016] [Indexed: 11/19/2022]
Abstract
BACKGROUND Bacterial cowshed isolates are allergy protective in mice; however, the underlying mechanisms are largely unknown. We examined the ability of Lactococcus lactis G121 to prevent allergic inflammatory reactions. OBJECTIVE We sought to identify the ligands and pattern recognition receptors through which L lactis G121 confers allergy protection. METHODS L lactis G121-induced cytokine release and surface expression of costimulatory molecules by untreated or inhibitor-treated (bafilomycin and cytochalasin D) human monocyte-derived dendritic cells (moDCs), bone marrow-derived mouse dendritic cells (BMDCs), and moDC/naive CD4+ T-cell cocultures were analyzed by using ELISA and flow cytometry. The pathology of ovalbumin-induced acute allergic airway inflammation after adoptive transfer of BMDCs was examined by means of microscopy. RESULTS L lactis G121-treated murine BMDCs and human moDCs released TH1-polarizing cytokines and induced TH1 T cells. Inhibiting phagocytosis and endosomal acidification in BMDCs or moDCs impaired the release of TH1-polarizing cytokines, costimulatory molecule expression, and T-cell activation on L lactis G121 challenge. In vivo allergy protection mediated by L lactis G121 was dependent on endosomal acidification in dendritic cells (DCs). Toll-like receptor (Tlr) 13-/- BMDCs showed a weak response to L lactis G121 and were unresponsive to its RNA. The TH1-polarizing activity of L lactis G121-treated human DCs was blocked by TLR8-specific inhibitors, mediated by L lactis G121 RNA, and synergistically enhanced by activation of nucleotide-binding oligomerization domain-containing protein (NOD) 2. CONCLUSION Bacterial RNA is the main driver of L lactis G121-mediated protection against experimentally induced allergy and requires both bacterial uptake by DCs and endosomal acidification. In mice L lactis G121 RNA signals through TLR13; however, the most likely intracellular receptor in human subjects is TLR8.
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Affiliation(s)
- Karina Stein
- Division of Innate Immunity, Research Center Borstel, Airway Research Center North, German Center for Lung Research (DZL), Germany
| | | | - André Jenckel
- Division of Innate Immunity, Research Center Borstel, Airway Research Center North, German Center for Lung Research (DZL), Germany
| | - Anna Sigmund
- Institute of Medical Microbiology, University of Duisburg-Essen, Essen, Germany
| | - Zhijian James Chen
- Department of Molecular Biology, Howard Hughes Medical Institute, UT Southwestern Medical School, Dallas, Tex
| | | | | | - Holger Heine
- Division of Innate Immunity, Research Center Borstel, Airway Research Center North, German Center for Lung Research (DZL), Germany.
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168
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Pektor S, Bausbacher N, Otto G, Lawaczeck L, Grabbe S, Schreckenberger M, Miederer M. Toll like receptor mediated immune stimulation can be visualized in vivo by [ 18F]FDG-PET. Nucl Med Biol 2016; 43:651-660. [PMID: 27552488 DOI: 10.1016/j.nucmedbio.2016.07.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 06/13/2016] [Accepted: 07/11/2016] [Indexed: 01/19/2023]
Abstract
INTRODUCTION High uptake of [18F]-2-fluorodeoxyglucose ([18F]FDG) by inflammatory cells is a frequent cause of false positive results in [18F]FDG-positron-emission tomography (PET) for cancer diagnostics. Similar to cancer cells, immune cells undergo significant increases in glucose utilization following activation, e.g., in infectious diseases or after vaccination during cancer therapy. The aim of this study was to quantify certain immune effects in vitro and in vivo by [18F]FDG-PET after stimulation with TLR ligands and specific antibodies. METHODS In vivo [18F]FDG-PET/magnetic resonance imaging (MRI) and biodistribution was performed with C57BL/6 mice immunized with CpG or LPS. Cellular [18F]FDG-uptake assays were performed with B cells and T cells or with whole spleen cells after stimulation with CpG, LPS and anti-CD3/CD28. In vitro and in vivo activation of B and T cells was examined by concomitant FACS analysis to correlate immune cell activation with the strength of [18F]FDG accumulation. RESULTS We could show that TLR mediated activation of B cells increases [18F]FDG uptake, and that B cells show faster kinetics and greater effect than T cells stimulated by the CD3/CD28 pathway. In the whole spleen cell population the [18F]FDG signal was triggered mainly by the activation of B cells, corresponding closely to expression of typical stimulation markers. This finding could also been seen in vivo in [18F]FDG-PET/MRI, where the spleen was clearly visible after TLR stimulation and B cells showed upregulation of CD80 and CD86. CONCLUSION In vivo TLR stimulation can be visualized by increased [18F]FDG uptake in lymphoid organs. The signal generated in the spleen after immunization might be mainly attributed to the activation of B cells within. ADVANCES IN KNOWLEDGE AND IMPLICATIONS FOR PATIENT CARE Knowledge of the composition of cells that take up [18F]FDG during vaccination or in response to therapy may improve successful treatment of cancer patients in the future.
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Affiliation(s)
- Stefanie Pektor
- Department of Nuclear Medicine, University Medical Center Mainz, Germany.
| | - Nicole Bausbacher
- Department of Nuclear Medicine, University Medical Center Mainz, Germany
| | - Georg Otto
- Department of Nuclear Medicine, University Medical Center Mainz, Germany
| | - Laura Lawaczeck
- Department of Nuclear Medicine, University Medical Center Mainz, Germany
| | - Stephan Grabbe
- Department of Dermatology, University Medical Center Mainz, Germany
| | | | - Matthias Miederer
- Department of Nuclear Medicine, University Medical Center Mainz, Germany
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169
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Medvedev AE, Murphy M, Zhou H, Li X. E3 ubiquitin ligases Pellinos as regulators of pattern recognition receptor signaling and immune responses. Immunol Rev 2016; 266:109-22. [PMID: 26085210 DOI: 10.1111/imr.12298] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Pellinos are a family of E3 ubiquitin ligases discovered for their role in catalyzing K63-linked polyubiquitination of Pelle, an interleukin-1 (IL-1) receptor-associated kinase homolog in the Drosophila Toll pathway. Subsequent studies have revealed the central and non-redundant roles of mammalian Pellino-1, Pellino-2, and Pelino-3 in signaling pathways emanating from IL-1 receptors, Toll-like receptors, NOD-like receptors, T- and B-cell receptors. While Pellinos ability to interact with many signaling intermediates suggested their scaffolding roles, recent findings in mice expressing ligase-inactive Pellinos demonstrated the importance of Pellino ubiquitin ligase activity. Cell-specific functions of Pellinos have emerged, e.g. Pellino-1 being a negative regulator in T lymphocytes and a positive regulator in myeloid cells, and details of molecular regulation of receptor signaling by various members of the Pellino family have been revealed. In this review, we summarize current information about Pellino-mediated regulation of signaling by pattern recognition receptors, T-cell and B-cell receptors and tumor necrosis factor receptors, and discuss Pellinos roles in sepsis and infectious diseases, as well as in autoimmune, inflammatory, and allergic disorders. We also provide our perspective on the potential of targeting Pellinos with peptide- or small molecule-based drug compounds as a new therapeutic approach for septic shock and autoimmune pathologies.
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Affiliation(s)
- Andrei E Medvedev
- Department of Immunology, University of Connecticut Health Center, Farmington, CT, USA
| | - Michael Murphy
- Department of Immunology, University of Connecticut Health Center, Farmington, CT, USA
| | - Hao Zhou
- Department of Immunology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Xiaoxia Li
- Department of Immunology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
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170
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Dawson HD, Smith AD, Chen C, Urban JF. An in-depth comparison of the porcine, murine and human inflammasomes; lessons from the porcine genome and transcriptome. Vet Microbiol 2016; 202:2-15. [PMID: 27321134 DOI: 10.1016/j.vetmic.2016.05.013] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 04/26/2016] [Accepted: 05/26/2016] [Indexed: 12/14/2022]
Abstract
Emerging evidence suggests that swine are a scientifically acceptable intermediate species between rodents and humans to model immune function relevant to humans. The swine genome has recently been sequenced and several preliminary structural and functional analysis of the porcine immunome have been published. Herein we provide an expanded in silico analysis using an improved assembly of the porcine transcriptome that provides an in depth analysis of genes that are related to inflammasomes, responses to Toll-like receptor ligands, and M1 macrophage polarization and Escherichia coli as a model organism. Comparisons of the expansion or contraction of orthologous gene families indicated more similar rates and classes of genes in humans and pigs than in mice; however several novel porcine or artiodactyl-specific paralogs or pseudogenes were identified. Conservation of homology and structural motifs of orthologs revealed that the overall similarity to human proteins was significantly higher for pigs compared to mouse. Despite these similarities, two out of four canonical inflammasome pathways, Absent in melanoma 2 (AIM2) and NLR family and CARD domain containing 4 (NLRC4), were found to be missing in pigs. Pig M1 Mφ polarization in response to interferon-γ (IFN-γ) and lipopolysaccharide (LPS) was assessed, via the transcriptome, using next generation sequencing. Our analysis revealed predominantly human-like responses however some, mouse-like responses were observed, as well as induction of numerous pig or artiodactyl-specific genes. This work supports using swine to model both human immunological and inflammatory responses to infection. However, caution must be exercised as pigs differ from humans in several fundamental pathways.
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Affiliation(s)
- Harry D Dawson
- Rm 224, Bld 307C, Beltsville Human Nutrition Research Center, Beltsville, MD 20705, USA; U.S. Department of Agriculture, Agricultural Research Service, Beltsville Human Nutrition Research Center, Diet, Genomics and Immunology Laboratory, Beltsville, MD 20705, USA.
| | - Allen D Smith
- U.S. Department of Agriculture, Agricultural Research Service, Beltsville Human Nutrition Research Center, Diet, Genomics and Immunology Laboratory, Beltsville, MD 20705, USA
| | - Celine Chen
- U.S. Department of Agriculture, Agricultural Research Service, Beltsville Human Nutrition Research Center, Diet, Genomics and Immunology Laboratory, Beltsville, MD 20705, USA
| | - Joseph F Urban
- U.S. Department of Agriculture, Agricultural Research Service, Beltsville Human Nutrition Research Center, Diet, Genomics and Immunology Laboratory, Beltsville, MD 20705, USA
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171
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Murphy MB, Medvedev AE. Long noncoding RNAs as regulators of Toll-like receptor signaling and innate immunity. J Leukoc Biol 2016; 99:839-50. [PMID: 26965636 PMCID: PMC6608019 DOI: 10.1189/jlb.2ru1215-575r] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 02/18/2016] [Accepted: 02/23/2016] [Indexed: 12/30/2022] Open
Abstract
Sensing of microbial pathogens and endogenous "alarmins" by macrophages and dendritic cells is reliant on pattern recognition receptors, including membrane-associated TLRs, cytosolic nucleotide-binding and oligomerization domain leucine-rich repeat-containing receptors, retinoic acid-inducible gene I-like receptors, and absent in melanoma 2-like receptors. Engagement of TLRs elicits signaling pathways that activate inflammatory genes whose expression is regulated by chromatin-modifying complexes and transcription factors. Long noncoding RNAs have emerged as new regulators of inflammatory mediators in the immune system. They are expressed in macrophages, dendritic cells, neutrophils, NK cells, and T- and B-lymphocytes and are involved in immune cell differentiation and activation. Long noncoding RNAs act via repression or activation of transcription factors, modulation of stability of mRNA and microRNA, regulation of ribosome entry and translation of mRNAs, and controlling components of the epigenetic machinery. In this review, we focus on recent advances in deciphering the mechanisms by which long noncoding RNAs regulate TLR-driven responses in macrophages and dendritic cells and discuss the involvement of long noncoding RNAs in endotoxin tolerance, autoimmune, and inflammatory diseases. The dissection of the role of long noncoding RNAs will improve our understanding of the mechanisms of regulation of inflammation and may provide new targets for therapeutic intervention.
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Affiliation(s)
- Michael B Murphy
- Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Andrei E Medvedev
- Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut, USA
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172
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Wang J, Zhang Z, Liu J, Zhao J, Yin D. Ectodomain Architecture Affects Sequence and Functional Evolution of Vertebrate Toll-like Receptors. Sci Rep 2016; 6:26705. [PMID: 27216145 PMCID: PMC4877655 DOI: 10.1038/srep26705] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 05/05/2016] [Indexed: 02/08/2023] Open
Abstract
Toll-like receptors (TLRs) are crucial components of innate immunity that specifically recognize diverse pathogen-associated molecular patterns from pathogens. The continuous hydrogen-bond network (asparagine ladder) formed among the asparagine residues on the concave surfaces of neighboring leucine-rich repeat modules assists in stabilizing the overall shape of TLR ectodomains responsible for ligand recognition. Analysis of 28 types of vertebrate TLRs showed that their ectodomains possessed three types of architectures: a single-domain architecture with an intact asparagine ladder, a three-domain architecture with the ladder interrupted in the middle, and a trans-three-domain architecture with the ladder broken in both termini. Based on a phylogenetic analysis, the three vertebrate TLR architectures arose during early evolution. The 1428 vertebrate TLRs can be divided into eight families based on sequence and structural differences. TLRs ligand specificities are affected by their ectodomain architectures. Three-domain TLRs bind hydrophobic ligands, whereas single-domain and trans-three-domain TLRs mainly recognize hydrophilic ligands. Analysis of 39 vertebrate genomes suggested that the number of single-domain TLR genes in terrestrial vertebrate genomes decreased by half compared to aquatic vertebrate genomes. Single-domain TLR genes underwent stronger purifying selective pressures than three-domain TLR genes in mammals. Overall, ectodomain architecture influences the sequence and functional evolution of vertebrate TLRs.
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Affiliation(s)
- Jinlan Wang
- Institute of Developmental Biology, School of Life Science, Shandong University, Jinan 250100, China
| | - Zheng Zhang
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan 250100, China
| | - Jing Liu
- Institute of Developmental Biology, School of Life Science, Shandong University, Jinan 250100, China
| | - Jing Zhao
- Institute of Developmental Biology, School of Life Science, Shandong University, Jinan 250100, China
| | - Deling Yin
- School of Pharmacy, Central South University, Changsha 410013, China.,Department of Internal Medicine, College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
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173
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Dowling JK, Mansell A. Toll-like receptors: the swiss army knife of immunity and vaccine development. Clin Transl Immunology 2016; 5:e85. [PMID: 27350884 PMCID: PMC4910119 DOI: 10.1038/cti.2016.22] [Citation(s) in RCA: 178] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 03/31/2016] [Accepted: 04/05/2016] [Indexed: 12/27/2022] Open
Abstract
Innate immune cells have a critical role in defense against infection and disease. Central to this is the broad specificity with which they can detect pathogen-associated patterns and danger-associated patterns via the pattern recognition receptors (PRRs) they express. Several families of PRRs have been identified including: Toll-like receptors (TLRs), C-type lectin-like receptors, retinoic acid-inducible gene-like receptors and nucleotide-binding oligomerization domain-like receptors. TLRs are one of the most largely studied families of PRRs. The binding of ligands to TLRs on antigen presenting cells (APCs), mainly dendritic cells, leads to APC maturation, induction of inflammatory cytokines and the priming of naive T cells to drive acquired immunity. Therefore, activation of TLRs promotes both innate inflammatory responses and the induction of adaptive immunity. Consequently, in the last two decades mounting evidence has inextricably linked TLR activation with the pathogenesis of immune diseases and cancer. It has become advantageous to harness these aspects of TLR signaling therapeutically to accelerate and enhance the induction of vaccine-specific responses and also target TLRs with the use of biologics and small molecule inhibitors for the treatment of disease. In these respects, TLRs may be considered a 'Swiss Army' knife of the immune system, ready to respond in a multitude of infectious and disease states. Here we describe the latest advances in TLR-targeted therapeutics and the use of TLR ligands as vaccine adjuvants.
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Affiliation(s)
- Jennifer K Dowling
- Pattern Recognition Receptors and Inflammation Research group, Centre for Innate Immunity and Infectious Disease, Hudson Institute of Medical Research, Melbourne, Victoria, Australia; Monash University, Clayton, Victoria, Australia
| | - Ashley Mansell
- Pattern Recognition Receptors and Inflammation Research group, Centre for Innate Immunity and Infectious Disease, Hudson Institute of Medical Research, Melbourne, Victoria, Australia; Monash University, Clayton, Victoria, Australia
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174
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Zhang Q, Yoo D. Immune evasion of porcine enteric coronaviruses and viral modulation of antiviral innate signaling. Virus Res 2016; 226:128-141. [PMID: 27212682 PMCID: PMC7111337 DOI: 10.1016/j.virusres.2016.05.015] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 05/16/2016] [Accepted: 05/17/2016] [Indexed: 12/15/2022]
Abstract
Enteric coronaviruses have evolved to modulate the host innate immunity. Viral IFN antagonists have been identified and they are mostly redundant. For protection of intestinal epithelia from enteric viruses, type III IFN plays a major role.
Porcine epidemic diarrhea virus (PEDV) and porcine deltacoronavirus (PDCoV) are emerged and reemerging viruses in pigs, and together with transmissible gastroenteritis virus (TGEV), pose significant economic concerns to the swine industry. These viruses infect epithelial cells of the small intestine and cause watery diarrhea, dehydration, and a high mortality in neonatal piglets. Type I interferons (IFN-α/β) are major antiviral cytokines forming host innate immunity, and in turn, these enteric coronaviruses have evolved to modulate the host innate immune signaling during infection. Accumulating evidence however suggests that IFN induction and signaling in the intestinal epithelial cells differ from other epithelial cells, largely due to distinct features of the gut epithelial mucosal surface and commensal microflora, and it appears that type III interferon (IFN-λ) plays a key role to maintain the antiviral state in the gut. This review describes the recent understanding on the immune evasion strategies of porcine enteric coronaviruses and the role of different types of IFNs for intestinal antiviral innate immunity.
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Affiliation(s)
- Qingzhan Zhang
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana IL, United States
| | - Dongwan Yoo
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana IL, United States.
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175
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Becattini S, Taur Y, Pamer EG. Antibiotic-Induced Changes in the Intestinal Microbiota and Disease. Trends Mol Med 2016; 22:458-478. [PMID: 27178527 DOI: 10.1016/j.molmed.2016.04.003] [Citation(s) in RCA: 514] [Impact Index Per Article: 64.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 04/13/2016] [Accepted: 04/13/2016] [Indexed: 12/12/2022]
Abstract
The gut microbiota is a key player in many physiological and pathological processes occurring in humans. Recent investigations suggest that the efficacy of some clinical approaches depends on the action of commensal bacteria. Antibiotics are invaluable weapons to fight infectious diseases. However, by altering the composition and functions of the microbiota, they can also produce long-lasting deleterious effects for the host. The emergence of multidrug-resistant pathogens raises concerns about the common, and at times inappropriate, use of antimicrobial agents. Here we review the most recently discovered connections between host pathophysiology, microbiota, and antibiotics highlighting technological platforms, mechanistic insights, and clinical strategies to enhance resistance to diseases by preserving the beneficial functions of the microbiota.
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Affiliation(s)
- Simone Becattini
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Ying Taur
- Infectious Diseases Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Lucille Castori Center for Microbes, Inflammation and Cancer, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Eric G Pamer
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Infectious Diseases Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Lucille Castori Center for Microbes, Inflammation and Cancer, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
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176
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The expanding universe of ribonucleoproteins: of novel RNA-binding proteins and unconventional interactions. Pflugers Arch 2016; 468:1029-40. [PMID: 27165283 PMCID: PMC4893068 DOI: 10.1007/s00424-016-1819-4] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 03/29/2016] [Accepted: 04/01/2016] [Indexed: 02/06/2023]
Abstract
Post-transcriptional regulation of gene expression plays a critical role in almost all cellular processes. Regulation occurs mostly by RNA-binding proteins (RBPs) that recognise RNA elements and form ribonucleoproteins (RNPs) to control RNA metabolism from synthesis to decay. Recently, the repertoire of RBPs was significantly expanded owing to methodological advances such as RNA interactome capture. The newly identified RNA binders are involved in diverse biological processes and belong to a broad spectrum of protein families, many of them exhibiting enzymatic activities. This suggests the existence of an extensive crosstalk between RNA biology and other, in principle unrelated, cell functions such as intermediary metabolism. Unexpectedly, hundreds of new RBPs do not contain identifiable RNA-binding domains (RBDs), raising the question of how they interact with RNA. Despite the many functions that have been attributed to RNA, our understanding of RNPs is still mostly governed by a rather protein-centric view, leading to the idea that proteins have evolved to bind to and regulate RNA and not vice versa. However, RNPs formed by an RNA-driven interaction mechanism (RNA-determined RNPs) are abundant and offer an alternative explanation for the surprising lack of classical RBDs in many RNA-interacting proteins. Moreover, RNAs can act as scaffolds to orchestrate and organise protein networks and directly control their activity, suggesting that nucleic acids might play an important regulatory role in many cellular processes, including metabolism.
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177
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Castiglia V, Piersigilli A, Ebner F, Janos M, Goldmann O, Damböck U, Kröger A, Weiss S, Knapp S, Jamieson AM, Kirschning C, Kalinke U, Strobl B, Müller M, Stoiber D, Lienenklaus S, Kovarik P. Type I Interferon Signaling Prevents IL-1β-Driven Lethal Systemic Hyperinflammation during Invasive Bacterial Infection of Soft Tissue. Cell Host Microbe 2016; 19:375-87. [PMID: 26962946 DOI: 10.1016/j.chom.2016.02.003] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2015] [Revised: 12/19/2015] [Accepted: 02/11/2016] [Indexed: 12/12/2022]
Abstract
Type I interferons (IFN-Is) are fundamental for antiviral immunity, but their role in bacterial infections is contradictory and incompletely described. Streptococcus pyogenes activates IFN-I production in innate immune cells, and IFN-I receptor 1 (Ifnar1)-deficient mice are highly susceptible to S. pyogenes infection. Here we report that IFN-I signaling protects the host against invasive S. pyogenes infection by restricting inflammation-driven damage in distant tissues. Lethality following infection in Ifnar1-deficient mice is caused by systemically exacerbated levels of the proinflammatory cytokine IL-1β. Critical cellular effectors of IFN-I in vivo are LysM+ and CD11c+ myeloid cells, which exhibit suppression of Il1b transcription upon Ifnar1 engagement. These cells are also the major source of IFN-β, which is significantly induced by S. pyogenes 23S rRNA in an Irf5-dependent manner. Our study establishes IL-1β and IFN-I levels as key homeostatic variables of protective, yet tuned, immune responses against severe invasive bacterial infection.
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Affiliation(s)
- Virginia Castiglia
- Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter (VBC), 1030 Vienna, Austria
| | - Alessandra Piersigilli
- Institute of Animal Pathology (COMPATH), University of Bern, 3012 Bern, Switzerland; Life Science Faculty, EPFL, 1015 Lausanne, Switzerland
| | - Florian Ebner
- Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter (VBC), 1030 Vienna, Austria
| | - Marton Janos
- Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter (VBC), 1030 Vienna, Austria
| | - Oliver Goldmann
- Infection Immunology Research Group, Helmholtz Center for Infection Research, 38124 Braunschweig, Germany
| | - Ursula Damböck
- Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter (VBC), 1030 Vienna, Austria
| | - Andrea Kröger
- Institute of Medical Microbiology, Otto-von-Guericke-University, 39106 Magdeburg, Germany; Department of Molecular Immunology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
| | - Sigfried Weiss
- Department of Molecular Immunology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
| | - Sylvia Knapp
- Center for Molecular Medicine of the Austrian Academy of Sciences, 1090 Vienna, Austria; Department of Medicine I, Laboratory of Infection Biology, Medical University of Vienna, 1090 Vienna, Austria
| | - Amanda M Jamieson
- Division of Biology and Medicine, Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912, USA
| | - Carsten Kirschning
- Institute of Medical Microbiology, University of Duisburg-Essen, 45147 Essen, Germany
| | - Ulrich Kalinke
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover Medical School and Helmholtz Centre for Infection Research, 30625 Hannover, Germany
| | - Birgit Strobl
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
| | - Mathias Müller
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
| | - Dagmar Stoiber
- Institute of Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; Ludwig Boltzmann Institute for Cancer Research, 1090 Vienna, Austria
| | - Stefan Lienenklaus
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover Medical School and Helmholtz Centre for Infection Research, 30625 Hannover, Germany; Institute for Laboratory Animal Science, Hannover Medical School, 30625 Hannover, Germany
| | - Pavel Kovarik
- Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter (VBC), 1030 Vienna, Austria.
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178
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Borrelia burgdorferi induces a type I interferon response during early stages of disseminated infection in mice. BMC Microbiol 2016; 16:29. [PMID: 26957120 PMCID: PMC4784397 DOI: 10.1186/s12866-016-0644-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 02/25/2016] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Lyme borrelia genotypes differ in their capacity to cause disseminated disease. Gene array analysis was employed to profile the host transcriptome induced by Borrelia burgdorferi strains with different capacities for causing disseminated disease in the blood of C3H/HeJ mice during early infection. RESULTS B. burgdorferi B515, a clinical isolate that causes disseminated infection in mice, differentially regulated 236 transcripts (P < 0.05 by ANOVA, with fold change of at least 2). The 216 significantly induced transcripts included interferon (IFN)-responsive genes and genes involved in immunity and inflammation. In contrast, B. burgdorferi B331, a clinical isolate that causes transient skin infection but does not disseminate in C3H/HeJ mice, stimulated changes in only a few genes (1 induced, 4 repressed). Transcriptional regulation of type I IFN and IFN-related genes was measured by quantitative RT-PCR in mouse skin biopsies collected from the site of infection 24 h after inoculation with B. burgdorferi. The mean values for transcripts of Ifnb, Cxcl10, Gbp1, Ifit1, Ifit3, Irf7, Mx1, and Stat2 were found to be significantly increased in B. burgdorferi strain B515-infected mice relative to the control group. In contrast, transcription of these genes was not significantly changed in response to B. burgdorferi strain B331 or B31-4, a mutant that is unable to disseminate. CONCLUSIONS These results establish a positive association between the disseminating capacity of B. burgdorferi and early type I IFN induction in a murine model of Lyme disease.
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179
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Ignacio A, Morales CI, Câmara NOS, Almeida RR. Innate Sensing of the Gut Microbiota: Modulation of Inflammatory and Autoimmune Diseases. Front Immunol 2016; 7:54. [PMID: 26925061 PMCID: PMC4759259 DOI: 10.3389/fimmu.2016.00054] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 02/04/2016] [Indexed: 12/13/2022] Open
Abstract
The mammalian gastrointestinal tract harbors a diverse microbial community with which dynamic interactions have been established over millennia of coevolution. Commensal bacteria and their products are sensed by innate receptors expressed in gut epithelia and in gut-associated immune cells, thereby promoting the proper development of mucosal immune system and host homeostasis. Many studies have demonstrated that host–microbiota interactions play a key role during local and systemic immunity. Therefore, this review will focus on how innate sensing of the gut microbiota and their metabolites through inflammasome and toll-like receptors impact the modulation of a distinct set of inflammatory and autoimmune diseases. We believe that a better understanding of the fine-tuning that governs host–microbiota interactions will further improve common prophylactic and therapeutic applications.
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Affiliation(s)
- Aline Ignacio
- Laboratory of Transplantation Immunobiology, Department of Immunology, Institute of Biomedical Sciences, University of São Paulo , São Paulo , Brazil
| | - Camila Ideli Morales
- Laboratory of Transplantation Immunobiology, Department of Immunology, Institute of Biomedical Sciences, University of São Paulo , São Paulo , Brazil
| | - Niels Olsen Saraiva Câmara
- Laboratory of Transplantation Immunobiology, Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil; Department of Medicine, Nephrology Division, Federal University of São Paulo, São Paulo, Brazil; Renal Pathophysiology Laboratory, Department of Clinical Medicine, University of São Paulo, São Paulo, Brazil
| | - Rafael Ribeiro Almeida
- Laboratory of Transplantation Immunobiology, Department of Immunology, Institute of Biomedical Sciences, University of São Paulo , São Paulo , Brazil
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180
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Ohto U, Shimizu T. Structural aspects of nucleic acid-sensing Toll-like receptors. Biophys Rev 2016; 8:33-43. [PMID: 28510149 DOI: 10.1007/s12551-015-0187-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 12/03/2015] [Indexed: 02/25/2023] Open
Abstract
Invading pathogens elicit potent immune responses in cells through interactions between structurally conserved molecules derived from the pathogens and specialized innate immune receptors such as the Toll-like receptors (TLRs). Nucleic acid is one of the principal TLR ligands. Nucleic acid-sensing TLRs recognize an array of nucleic acids, including double-stranded RNA, single-stranded RNA, and DNAs with specific sequence motifs. Although ligand-induced dimerization is commonly observed followed by TLR activation, both the specific recognition mechanisms and the ligand-receptor interactions vary among different TLRs. In this review, we highlight our current understanding of how these receptors recognize their cognate ligands based on the recent advances in structural biology.
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Affiliation(s)
- Umeharu Ohto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Toshiyuki Shimizu
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
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181
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Kolter J, Feuerstein R, Spoeri E, Gharun K, Elling R, Trieu-Cuot P, Goldmann T, Waskow C, Chen ZJ, Kirschning CJ, Deshmukh SD, Henneke P. Streptococci Engage TLR13 on Myeloid Cells in a Site-Specific Fashion. THE JOURNAL OF IMMUNOLOGY 2016; 196:2733-41. [PMID: 26873993 DOI: 10.4049/jimmunol.1501014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 01/14/2016] [Indexed: 12/11/2022]
Abstract
Streptococci are common human colonizers with a species-specific mucocutaneous distribution. At the same time, they are among the most important and most virulent invasive bacterial pathogens. Thus, site-specific cellular innate immunity, which is predominantly executed by resident and invading myeloid cells, has to be adapted with respect to streptococcal sensing, handling, and response. In this article, we show that TLR13 is the critical mouse macrophage (MΦ) receptor in the response to group B Streptococcus, both in bone marrow-derived MΦs and in mature tissue MΦs, such as those residing in the lamina propria of the colon and the dermis, as well as in microglia. In contrast, TLR13 and its chaperone UNC-93B are dispensable for a potent cytokine response of blood monocytes to group B Streptococcus, although monocytes serve as the key progenitors of intestinal and dermal MΦs. Furthermore, a specific role for TLR13 with respect to MΦ function is supported by the response to staphylococci, where TLR13 and UNC-93B limit the cytokine response in bone marrow-derived MΦs and microglia, but not in dermal MΦs. In summary, TLR13 is a critical and site-specific receptor in the single MΦ response to β-hemolytic streptococci.
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Affiliation(s)
- Julia Kolter
- Center for Chronic Immunodeficiency, Medical Center, University of Freiburg, 79106 Freiburg, Germany; Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Reinhild Feuerstein
- Center for Chronic Immunodeficiency, Medical Center, University of Freiburg, 79106 Freiburg, Germany; Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Evelyne Spoeri
- Center for Chronic Immunodeficiency, Medical Center, University of Freiburg, 79106 Freiburg, Germany
| | - Kourosh Gharun
- Center for Chronic Immunodeficiency, Medical Center, University of Freiburg, 79106 Freiburg, Germany; Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Roland Elling
- Center for Chronic Immunodeficiency, Medical Center, University of Freiburg, 79106 Freiburg, Germany; Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01655
| | - Patrick Trieu-Cuot
- Institute Pasteur, Unité de Biologie des Bactéries Pathogènes à Gram-Positif, CNRS ERL3526, 75724 Paris Cedex 15, France
| | - Tobias Goldmann
- Institute of Neuropathology, Medical Center, University of Freiburg, 79106 Freiburg, Germany
| | - Claudia Waskow
- Regeneration in Hematopoiesis and Animal Models of Hematopoiesis, Faculty of Medicine, Technical University, 01307 Dresden, Germany
| | - Zhijian J Chen
- Southwestern Medical School, University of Texas, Dallas, TX 75390
| | - Carsten J Kirschning
- Institute of Medical Microbiology, Medical Center, University of Essen, 45147 Essen, Germany
| | - Sachin D Deshmukh
- Center for Chronic Immunodeficiency, Medical Center, University of Freiburg, 79106 Freiburg, Germany; Center for Sepsis Control and Care, Medical Center, University of Jena, 07747 Jena, Germany; and
| | - Philipp Henneke
- Center for Chronic Immunodeficiency, Medical Center, University of Freiburg, 79106 Freiburg, Germany; Center for Pediatrics and Adolescent Medicine, Medical Center, University of Freiburg, 79106 Freiburg, Germany
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182
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Li J, Csakai A, Jin J, Zhang F, Yin H. Therapeutic Developments Targeting Toll-like Receptor-4-Mediated Neuroinflammation. ChemMedChem 2016; 11:154-65. [PMID: 26136385 PMCID: PMC4983275 DOI: 10.1002/cmdc.201500188] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Indexed: 02/06/2023]
Abstract
Toll-like receptors (TLRs) have been shown to play an important role in the immune system, which warrants study of their remarkable potential as pharmacological targets. Activation of TLRs requires participation from specific pathogen-associated molecular patterns (PAMPs) and accessory proteins such as myeloid differentiation protein 2 (MD2), lipopolysaccharide binding protein (LBP), and cluster differentiation antigen 14 (CD14). Assembly of the TLR4-MD2-LPS complex is essential in TLR4 activation. Recent studies have revealed that TLR4 activation is a significant trigger of signal transmission pathways in the nervous system, which could result in chronic pain as well as opioid tolerance and dependence. Researchers of the molecular structure of TLRs and their accessory proteins have opened a door to syntheses of TLRs agonists and antagonists, such as eritoran. Small-molecule modulators of TLR4, such as MD2-I and tricyclic antidepressants, offer more promising prospects than peptides, given their convenience in oral administration and lower cost. Herein we mainly discuss the mechanisms and clinical prospects of TLR4 agonists and antagonists.
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Affiliation(s)
- Jing Li
- Department of Rheumatology and Clinical Immunology, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Key Laboratory of Rheumatology and Clinical Immunology, Ministry of Education, Beijing, 100032, China
| | - Adam Csakai
- Department of Chemistry and Biochemistry and BioFrontiers Institute, University of Colorado, Boulder, CO, 80309-0596, USA
| | - Jialin Jin
- Center of Basic Molecular Science, Department of Chemistry, Tsinghua University, Beijing, 100082, China
- Physikalisch-Astronomische Fakultät, Abbe School of Photonics, Jena, 07743, Germany
| | - Fengchun Zhang
- Department of Rheumatology and Clinical Immunology, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Key Laboratory of Rheumatology and Clinical Immunology, Ministry of Education, Beijing, 100032, China.
| | - Hang Yin
- Department of Chemistry and Biochemistry and BioFrontiers Institute, University of Colorado, Boulder, CO, 80309-0596, USA.
- Center of Basic Molecular Science, Department of Chemistry, Tsinghua University, Beijing, 100082, China.
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183
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Wang J, Chai J, Wang H. Structure of the mouse Toll-like receptor 13 ectodomain in complex with a conserved sequence from bacterial 23S ribosomal RNA. FEBS J 2016; 283:1631-5. [PMID: 26676765 DOI: 10.1111/febs.13628] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Revised: 12/09/2015] [Accepted: 12/11/2015] [Indexed: 11/30/2022]
Abstract
Toll-like receptor 13 (TLR13) recognizes a conserved 10-nucleotide sequence from bacterial 23S ribosomal RNA, and binding of TLR13 to the target rRNA molecule triggers immune responses. Recently, the crystal structure of the TLR13 ectodomain bound by a 13-nucleotide single-stranded RNA (ssRNA13) was determined by using the initial phases provided by a cryo-electron microscopy map of TLR13 in complex with a 25-nucleotide ssRNA (ssRNA25). This structural snapshot describes a unique method for solving the crystal structure of the TLR13-ssRNA13 complex based on medium-resolution reconstruction of TLR13-ssRNA25 cryo-electron microscopy images.
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Affiliation(s)
- Jiawei Wang
- State Key Laboratory of Membrane Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Jijie Chai
- Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.,Ministry of Education Key Laboratory of Protein Science, School of Life Sciences, Tsinghua University, Beijing, China
| | - Hongwei Wang
- Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.,Ministry of Education Key Laboratory of Protein Science, School of Life Sciences, Tsinghua University, Beijing, China
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184
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Affiliation(s)
- Ralph Panstruga
- Unit of Plant Molecular Cell Biology, Institute for Biology I, RWTH Aachen University, Worringerweg 1, 52056, Aachen, Germany
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185
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Abstract
For many years innate immunity was regarded as a relatively nonspecific set of mechanisms serving as a first line of defence to contain infections while the more refined adaptive immune response was developing. The discovery of pattern recognition receptors (PRRs) revolutionised the prevailing view of innate immunity, revealing its intimate connection with adaptive immunity and generation of effector and memory T- and B-cell responses. Among the PRRs, families of Toll-like receptors (TLRs), C-type lectin receptors (CLR), retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) and nucleotide-binding domain, leucine-rich repeat-containing protein receptors (NLRs), along with a number of cytosolic DNA sensors and the family of absent in melanoma (AIM)-like receptors (ALRs), have been characterised. NLR sensors have been a particular focus of attention, and some NLRs have emerged as key orchestrators of the inflammatory response through the formation of large multiprotein complexes termed inflammasomes. However, several other functions not related to inflammasomes have also been described for NLRs. This chapter introduces the different families of PRRs, their signalling pathways, cross-regulation and their roles in immunosurveillance. The structure and function of NLRs is also discussed with particular focus on the non-inflammasome NLRs.
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186
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Dowling JK, Dellacasagrande J. Toll-Like Receptors: Ligands, Cell-Based Models, and Readouts for Receptor Action. Methods Mol Biol 2016; 1390:3-27. [PMID: 26803619 DOI: 10.1007/978-1-4939-3335-8_1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
This chapter details Toll-like receptors (TLRs) and the tools available to study their biology in vitro. Key parameters to consider before exploring TLR action such as receptor localization, signaling pathways, nature of ligands and cellular expression are introduced. Cellular models (i.e., host cells and readouts) based on the use of cell lines, primary cells, or whole blood are presented. The use of modified TLRs to circumvent some technical problems is also discussed.
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Affiliation(s)
- Jennifer K Dowling
- Hudson Institute of Medical Research, Monash University, 27-31 Wright St., Clayton, Melbourne, VIC, 3168, Australia.
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187
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Abstract
In the two decades since their initial discovery, DNA vaccines technologies have come a long way. Unfortunately, when applied to human subjects inadequate immunogenicity is still the biggest challenge for practical DNA vaccine use. Many different strategies have been tested in preclinical models to address this problem, including novel plasmid vectors and codon optimization to enhance antigen expression, new gene transfection systems or electroporation to increase delivery efficiency, protein or live virus vector boosting regimens to maximise immune stimulation, and formulation of DNA vaccines with traditional or molecular adjuvants. Better understanding of the mechanisms of action of DNA vaccines has also enabled better use of the intrinsic host response to DNA to improve vaccine immunogenicity. This review summarizes recent advances in DNA vaccine technologies and related intracellular events and how these might impact on future directions of DNA vaccine development.
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Affiliation(s)
- Lei Li
- a Vaxine Pty Ltd, Bedford Park , Adelaide , Australia.,b Department of Diabetes and Endocrinology , Flinders University, Flinders Medical Centre , Adelaide , SA , Australia
| | - Nikolai Petrovsky
- a Vaxine Pty Ltd, Bedford Park , Adelaide , Australia.,b Department of Diabetes and Endocrinology , Flinders University, Flinders Medical Centre , Adelaide , SA , Australia
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188
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Tanne A, Muniz LR, Puzio-Kuter A, Leonova KI, Gudkov AV, Ting DT, Monasson R, Cocco S, Levine AJ, Bhardwaj N, Greenbaum BD. Distinguishing the immunostimulatory properties of noncoding RNAs expressed in cancer cells. Proc Natl Acad Sci U S A 2015; 112:15154-9. [PMID: 26575629 PMCID: PMC4679042 DOI: 10.1073/pnas.1517584112] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Recent studies have demonstrated abundant transcription of a set of noncoding RNAs (ncRNAs) preferentially within tumors as opposed to normal tissue. Using an approach from statistical physics, we quantify global transcriptome-wide motif use for the first time, to our knowledge, in human and murine ncRNAs, determining that most have motif use consistent with the coding genome. However, an outlier subset of tumor-associated ncRNAs, typically of recent evolutionary origin, has motif use that is often indicative of pathogen-associated RNA. For instance, we show that the tumor-associated human repeat human satellite repeat II (HSATII) is enriched in motifs containing CpG dinucleotides in AU-rich contexts that most of the human genome and human adapted viruses have evolved to avoid. We demonstrate that a key subset of these ncRNAs functions as immunostimulatory "self-agonists" and directly activates cells of the mononuclear phagocytic system to produce proinflammatory cytokines. These ncRNAs arise from endogenous repetitive elements that are normally silenced, yet are often very highly expressed in cancers. We propose that the innate response in tumors may partially originate from direct interaction of immunogenic ncRNAs expressed in cancer cells with innate pattern recognition receptors, and thereby assign a previously unidentified danger-associated function to a set of dark matter repetitive elements. These findings potentially reconcile several observations concerning the role of ncRNA expression in cancers and their relationship to the tumor microenvironment.
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Affiliation(s)
- Antoine Tanne
- Tisch Cancer Institute, Department of Medicine, Hematology, and Medical Oncology, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Luciana R Muniz
- Tisch Cancer Institute, Department of Medicine, Hematology, and Medical Oncology, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | | | | | | | - David T Ting
- Massachusetts General Hospital, Charlestown, MA 02129
| | - Rémi Monasson
- Laboratoire de Physique Théorique, CNRS and Ecole Normale Supérieure, 75005 Paris, France
| | - Simona Cocco
- Laboratoire de Physique Statistique, CNRS and Ecole Normale Supérieure, 75005 Paris, France
| | - Arnold J Levine
- Rutgers Cancer Institute of New Jersey, New Brunswick, NJ 08903; The Simons Center for Systems Biology, School of Natural Sciences, Institute for Advanced Study, Princeton, NJ 08540;
| | - Nina Bhardwaj
- Tisch Cancer Institute, Department of Medicine, Hematology, and Medical Oncology, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Benjamin D Greenbaum
- Tisch Cancer Institute, Department of Medicine, Hematology, and Medical Oncology, Icahn School of Medicine at Mount Sinai, New York, NY 10029; The Simons Center for Systems Biology, School of Natural Sciences, Institute for Advanced Study, Princeton, NJ 08540; Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, NY 10029
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189
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Krüger A, Oldenburg M, Chebrolu C, Beisser D, Kolter J, Sigmund AM, Steinmann J, Schäfer S, Hochrein H, Rahmann S, Wagner H, Henneke P, Hornung V, Buer J, Kirschning CJ. Human TLR8 senses UR/URR motifs in bacterial and mitochondrial RNA. EMBO Rep 2015; 16:1656-63. [PMID: 26545385 PMCID: PMC4687425 DOI: 10.15252/embr.201540861] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 10/15/2015] [Indexed: 11/25/2022] Open
Abstract
Toll‐like receptor (TLR) 13 and TLR2 are the major sensors of Gram‐positive bacteria in mice. TLR13 recognizes Sa19, a specific 23S ribosomal (r) RNA‐derived fragment and bacterial modification of Sa19 ablates binding to TLR13, and to antibiotics such as erythromycin. Similarly, RNase A‐treated Staphylococcus aureus activate human peripheral blood mononuclear cells (PBMCs) only via TLR2, implying single‐stranded (ss) RNA as major stimulant. Here, we identify human TLR8 as functional TLR13 equivalent that promiscuously senses ssRNA. Accordingly, Sa19 and mitochondrial (mt) 16S rRNA sequence‐derived oligoribonucleotides (ORNs) stimulate PBMCs in a MyD88‐dependent manner. These ORNs, as well as S. aureus‐, Escherichia coli‐, and mt‐RNA, also activate differentiated human monocytoid THP‐1 cells, provided they express TLR8. Moreover, Unc93b1−/−‐ and Tlr8−/−‐THP‐1 cells are refractory, while endogenous and ectopically expressed TLR8 confers responsiveness in a UR/URR RNA ligand consensus motif‐dependent manner. If TLR8 function is inhibited by suppression of lysosomal function, antibiotic treatment efficiently blocks bacteria‐driven inflammatory responses in infected human whole blood cultures. Sepsis therapy might thus benefit from interfering with TLR8 function.
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Affiliation(s)
- Anne Krüger
- Institute of Medical Microbiology, University of Duisburg-Essen, Essen, Germany
| | - Marina Oldenburg
- Institute of Medical Microbiology, University of Duisburg-Essen, Essen, Germany
| | | | - Daniela Beisser
- Genome Informatics, Institute of Human Genetics, University of Duisburg-Essen, Essen, Germany
| | - Julia Kolter
- Centre of Chronic Immunodeficiency, University Medical Center Freiburg, Freiburg, Germany
| | - Anna M Sigmund
- Institute of Medical Microbiology, University of Duisburg-Essen, Essen, Germany
| | - Jörg Steinmann
- Institute of Medical Microbiology, University of Duisburg-Essen, Essen, Germany
| | - Simon Schäfer
- Clinic of Anesthesia, University of Duisburg-Essen, Essen, Germany
| | - Hubertus Hochrein
- Department of Research Immunology, Bavarian Nordic GmbH, Martinsried, Germany
| | - Sven Rahmann
- Genome Informatics, Institute of Human Genetics, University of Duisburg-Essen, Essen, Germany
| | - Hermann Wagner
- Institute for Medical Microbiology, Immunology and Hygiene, Technical University of Munich, Munich, Germany
| | - Philipp Henneke
- Centre of Chronic Immunodeficiency, University Medical Center Freiburg, Freiburg, Germany
| | - Veit Hornung
- Institute of Clinical Chemistry and Clinical Pharmacology, University of Bonn, Bonn, Germany
| | - Jan Buer
- Institute of Medical Microbiology, University of Duisburg-Essen, Essen, Germany
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190
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Shibata T, Ohto U, Nomura S, Kibata K, Motoi Y, Zhang Y, Murakami Y, Fukui R, Ishimoto T, Sano S, Ito T, Shimizu T, Miyake K. Guanosine and its modified derivatives are endogenous ligands for TLR7. Int Immunol 2015; 28:211-22. [PMID: 26489884 DOI: 10.1093/intimm/dxv062] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 10/12/2015] [Indexed: 12/20/2022] Open
Abstract
Toll-like receptor (TLR) 7and 8 were considered to recognize single-strand RNA (ssRNA) from viruses. Although these receptors also respond to synthetic small chemical ligands, such as CL075 and R848, it remains to be determined whether these receptors sense natural small molecules or not. In the structure of human TLR8 (huTLR8) with ssRNA, there are two ligand-binding sites: one binds a uridine and the other binds an oligoribonucleotide (ORN). This finding demonstrates that huTLR8 recognizes degradation products of ssRNA, suggesting the presence of natural small ligands. We here show that TLR7 works as the sensor for guanosine (G)/2'-deoxyguanosine (dG) in the presence of ORN where ORN strengthens TLR7 interaction with G/dG. In addition, modified nucleosides such as 7-methylguanosine, 8-hydroxyguanosine (8-OHG) and 8-hydroxydeoxyguanosine (8-OHdG) activated TLR7 with ORNs. Importantly, 8-OHdG-a well-known oxidative DNA damage marker with unknown function-induced strong cytokine production comparable to G and dG both in mouse and human immune cells. Although 8-OHdG bound TLR7/ORN with lower affinity than dG did in isothermal titration calorimetry, administered 8-OHdG was metabolically more stable than dG in the serum, indicating that 8-OHdG acts on TLR7 as an endogenous ligand in vivo To address a role of G analogs in the disease state, we also examined macrophages from Unc93b1 (D34A/D34A) mice, which suffer from TLR7-dependent systemic inflammation, and found that Unc93b1 (D34A/D34A) macrophages showed significantly enhanced response to G alone or 8-OHdG with ORN. In conclusion, our results provide evidence that G, dG, 8-OHG and 8-OHdG are novel endogenous ligands for TLR7.
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Affiliation(s)
- Takuma Shibata
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minatoku, Tokyo 108-8639, Japan CREST, Japan Science and Technology agency, 4-1-8, Honcho, Kawaguchi-shi, Saitama 332-0012, Japan
| | - Umeharu Ohto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Shosaku Nomura
- First Department of Internal Medicine, Kansai Medical University, Osaka 573-1010, Japan
| | - Kayoko Kibata
- First Department of Internal Medicine, Kansai Medical University, Osaka 573-1010, Japan
| | - Yuji Motoi
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minatoku, Tokyo 108-8639, Japan
| | - Yan Zhang
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minatoku, Tokyo 108-8639, Japan
| | - Yusuke Murakami
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minatoku, Tokyo 108-8639, Japan
| | - Ryutaro Fukui
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minatoku, Tokyo 108-8639, Japan
| | - Tatsushi Ishimoto
- Department of Dermatology, Kochi Medical School, Kochi University, Kohasu, Okocho, Nankoku 783-8505, Japan
| | - Shigetoshi Sano
- Department of Dermatology, Kochi Medical School, Kochi University, Kohasu, Okocho, Nankoku 783-8505, Japan
| | - Tomoki Ito
- First Department of Internal Medicine, Kansai Medical University, Osaka 573-1010, Japan
| | - Toshiyuki Shimizu
- CREST, Japan Science and Technology agency, 4-1-8, Honcho, Kawaguchi-shi, Saitama 332-0012, Japan Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kensuke Miyake
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minatoku, Tokyo 108-8639, Japan Laboratory of Innate Immunity, Center for Experimental Medicine and Systems Biology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minatoku, Tokyo 108-8639, Japan
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191
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Song W, Wang J, Han Z, Zhang Y, Zhang H, Wang W, Chang J, Xia B, Fan S, Zhang D, Wang J, Wang HW, Chai J. Structural basis for specific recognition of single-stranded RNA by Toll-like receptor 13. Nat Struct Mol Biol 2015; 22:782-7. [PMID: 26323037 DOI: 10.1038/nsmb.3080] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 08/06/2015] [Indexed: 12/16/2022]
Abstract
Toll-like receptors (TLRs) have crucial roles in innate immunity, functioning as pattern-recognition receptors. TLR13 recognizes a conserved sequence from bacterial 23S rRNA and then triggers an immune response. Here we report the crystal structure of the mouse TLR13 ectodomain bound by a 13-nt single-stranded (ss) RNA derived from 23S rRNA. The ssRNA induces TLR13 dimerization but assumes a stem-loop-like structure that is completely different from that in the bacterial ribosome but nevertheless is crucial for TLR13 recognition. Most of the RNA nucleotides are splayed out to make base-specific contacts with the concave surface of TLR13, and RNA-specific interactions are important to allow TLR13 to distinguish RNA from DNA. Interestingly, a viral-derived 16-nt ssRNA predicted to form a similar stem-loop-like structure also induces TLR13 activation. Together, our results reveal the structural mechanism of TLR13's sequence- and conformation-specific recognition of ssRNA.
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Affiliation(s)
- Wen Song
- Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Jia Wang
- Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Zhifu Han
- Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Yifan Zhang
- Center for Infectious and Inflammatory Diseases, Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, Texas, USA
| | - Heqiao Zhang
- Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Weiguang Wang
- Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Junbiao Chang
- Collaborative Innovation Center of New Drug Research and Safety Evaluation, Zhengzhou University, Zhengzhou, China
| | - Bingshu Xia
- Center for Infectious and Inflammatory Diseases, Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, Texas, USA
| | - Shilong Fan
- Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Dekai Zhang
- Center for Infectious and Inflammatory Diseases, Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, Texas, USA
| | - Jiawei Wang
- Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Hong-Wei Wang
- Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Jijie Chai
- Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Tsinghua-Peking Center for Life Sciences, Beijing, China
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192
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Thornton CS, Grinwis ME, Sibley CD, Parkins MD, Rabin HR, Surette MG. Antibiotic susceptibility and molecular mechanisms of macrolide resistance in streptococci isolated from adult cystic fibrosis patients. J Med Microbiol 2015; 64:1375-1386. [PMID: 26408040 DOI: 10.1099/jmm.0.000172] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The cystic fibrosis (CF) airways are colonized by polymicrobial communities with high bacterial load and are influenced by frequent antibiotic exposures. This community includes diverse streptococci, some of which have been directly or indirectly associated with pulmonary exacerbations. As many streptococci are naturally competent, horizontal transfer of antibiotic-resistant determinants coupled with frequent and/or chronic antibiotic exposure may contribute to high resistance rates. In this study, we assessed antibiotic resistance in 413 streptococcal isolates from adult CF patients against nine antibiotics relevant in CF treatment. We observed very low rates of cephalosporin resistance [cefepime and ceftriaxone ( < 2%)], and higher rates of resistance to tetracycline (∼34%) and sulfamethoxazole/trimethoprim (∼45%). The highest rate of antibiotic resistance was to the macrolides [azithromycin (56.4%) and erythromycin (51.6%)]. We also investigated the molecular mechanisms of macrolide resistance and found that only half of our macrolide-resistant streptococci isolates contained the mef (efflux pump) or erm (methylation of 23S ribosomal target site) genes. The majority of isolates were, however, found to have point mutations at position 2058 or 2059 of the 23S ribosomal subunit - a molecular mechanism of resistance not commonly reported in the non-pyogenic and non-pneumococcal streptococci, and unique in comparison with previous studies. The high rates of resistance observed here may result in poor outcomes where specific streptococci are contributing to CF airway disease and serve as a reservoir of resistance genes within the CF airway microbiome.
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Affiliation(s)
- Christina S Thornton
- Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Margot E Grinwis
- Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Christopher D Sibley
- Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Michael D Parkins
- Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta T2N 4N1, Canada.,Department of Medicine, University of Calgary, Calgary, Alberta T2N 4N1, Canada.,Adult Cystic Fibrosis Clinic, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Harvey R Rabin
- Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta T2N 4N1, Canada.,Department of Medicine, University of Calgary, Calgary, Alberta T2N 4N1, Canada.,Adult Cystic Fibrosis Clinic, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Michael G Surette
- Farncombe Family Digestive Health Research Institute, Department of Medicine, McMaster University, Hamilton, Ontario L8S 4L8, Canada.,Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta T2N 4N1, Canada
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193
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Pinheiro A, Neves F, Lemos de Matos A, Abrantes J, van der Loo W, Mage R, Esteves PJ. An overview of the lagomorph immune system and its genetic diversity. Immunogenetics 2015; 68:83-107. [PMID: 26399242 DOI: 10.1007/s00251-015-0868-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 08/31/2015] [Indexed: 01/11/2023]
Abstract
Our knowledge of the lagomorph immune system remains largely based upon studies of the European rabbit (Oryctolagus cuniculus), a major model for studies of immunology. Two important and devastating viral diseases, rabbit hemorrhagic disease and myxomatosis, are affecting European rabbit populations. In this context, we discuss the genetic diversity of the European rabbit immune system and extend to available information about other lagomorphs. Regarding innate immunity, we review the most recent advances in identifying interleukins, chemokines and chemokine receptors, Toll-like receptors, antiviral proteins (RIG-I and Trim5), and the genes encoding fucosyltransferases that are utilized by rabbit hemorrhagic disease virus as a portal for invading host respiratory and gut epithelial cells. Evolutionary studies showed that several genes of innate immunity are evolving by strong natural selection. Studies of the leporid CCR5 gene revealed a very dramatic change unique in mammals at the second extracellular loop of CCR5 resulting from a gene conversion event with the paralogous CCR2. For the adaptive immune system, we review genetic diversity at the loci encoding antibody variable and constant regions, the major histocompatibility complex (RLA) and T cells. Studies of IGHV and IGKC genes expressed in leporids are two of the few examples of trans-species polymorphism observed outside of the major histocompatibility complex. In addition, we review some endogenous viruses of lagomorph genomes, the importance of the European rabbit as a model for human disease studies, and the anticipated role of next-generation sequencing in extending knowledge of lagomorph immune systems and their evolution.
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Affiliation(s)
- Ana Pinheiro
- InBIO-Research Network in Biodiversity and Evolutionary Biology, CIBIO, Universidade do Porto, Campus Agrário de Vairão, Rua Padre Armando Quintas, nr. 7, 4485-661, Vairão, Portugal
- Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, 4169-007, Porto, Portugal
- SaBio-IREC (CSIC-UCLM-JCCM), Ronda de Toledo s/n, 13071, Ciudad Real, Spain
| | - Fabiana Neves
- InBIO-Research Network in Biodiversity and Evolutionary Biology, CIBIO, Universidade do Porto, Campus Agrário de Vairão, Rua Padre Armando Quintas, nr. 7, 4485-661, Vairão, Portugal
- UMIB/UP-Unidade Multidisciplinar de Investigação Biomédica, Universidade do Porto, Porto, Portugal
| | - Ana Lemos de Matos
- Department of Molecular Genetics & Microbiology, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Joana Abrantes
- InBIO-Research Network in Biodiversity and Evolutionary Biology, CIBIO, Universidade do Porto, Campus Agrário de Vairão, Rua Padre Armando Quintas, nr. 7, 4485-661, Vairão, Portugal
| | - Wessel van der Loo
- InBIO-Research Network in Biodiversity and Evolutionary Biology, CIBIO, Universidade do Porto, Campus Agrário de Vairão, Rua Padre Armando Quintas, nr. 7, 4485-661, Vairão, Portugal
| | - Rose Mage
- NIAID, NIH, Bethesda, MD, 20892, USA
| | - Pedro José Esteves
- InBIO-Research Network in Biodiversity and Evolutionary Biology, CIBIO, Universidade do Porto, Campus Agrário de Vairão, Rua Padre Armando Quintas, nr. 7, 4485-661, Vairão, Portugal.
- Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, 4169-007, Porto, Portugal.
- CITS-Centro de Investigação em Tecnologias de Saúde, CESPU, Gandra, Portugal.
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194
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McGlasson S, Jury A, Jackson A, Hunt D. Type I interferon dysregulation and neurological disease. Nat Rev Neurol 2015; 11:515-23. [PMID: 26303851 DOI: 10.1038/nrneurol.2015.143] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Type I interferon is an essential component of the brain's innate immune defence, conferring protection against viral infection. Recently, dysregulation of the type I interferon pathway has been implicated in the pathogenesis of a spectrum of neuroinfectious and neuroinflammatory disorders. Underactivity of the type I interferon response is associated with a predisposition to herpes simplex encephalitis. Conversely, a group of 'interferonopathic' disorders, characterized by severe neuroinflammation and overactivity of type I interferon, has been described. Elucidation of the genetic basis of these Mendelian neuroinflammatory diseases has uncovered important links between nucleic acid sensors, innate immune activation and neuroinflammatory disease. These mechanisms have an important role in the pathogenesis of more common polygenic diseases that can affect the brain, such as lupus and cerebral small vessel disease. In this article, we review the spectrum of neurological disease associated with type I interferon dysregulation, as well as advances in our understanding of the molecular and cellular pathogenesis of these conditions. We highlight the potential utility of type I interferon as both a biomarker and a therapeutic target in neuroinflammatory disease.
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Affiliation(s)
- Sarah McGlasson
- MRC Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Crewe Road, Edinburgh EH4 2XU, UK
| | - Alexa Jury
- MRC Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Crewe Road, Edinburgh EH4 2XU, UK
| | - Andrew Jackson
- MRC Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Crewe Road, Edinburgh EH4 2XU, UK
| | - David Hunt
- MRC Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Crewe Road, Edinburgh EH4 2XU, UK
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195
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Bhattacharyya S, Varga J. Emerging roles of innate immune signaling and toll-like receptors in fibrosis and systemic sclerosis. Curr Rheumatol Rep 2015; 17:474. [PMID: 25604573 DOI: 10.1007/s11926-014-0474-z] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Pathological fibrosis is a distinguishing hallmark of systemic sclerosis (SSc) as well as a number of more common conditions. Fibrosis is a complex and dynamic process associated with immune dysregulation, vasculopathy, and uncontrolled extracellular matrix production leading to intractable scar formation in the skin and internal organs. Persistent or recurrent chemical, infectious, mechanical, or autoimmune injury in genetically predisposed individuals causes sustained fibroblasts activation. Innate immune signaling via toll-like receptors (TLRs) is increasingly recognized as a key player driving the persistent fibrotic response in SSc. In particular, expression of TLR4 as well as its endogenous ligands are elevated in lesional tissue from patients with SSc. Ligand-induced TLR4 activation elicits potent stimulatory effects on fibrotic gene expression and myofibroblast differentiation. Furthermore, TLR4 appears to sensitize fibroblasts to the profibrotic stimulatory effect of transforming growth factor-β. This review highlights recent advances and emerging paradigms for understanding the regulation, complex functional roles, and therapeutic potential of TLRs in SSc pathogenesis.
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Affiliation(s)
- Swati Bhattacharyya
- Division of Rheumatology, Northwestern University Feinberg School of Medicine, 240 E. Huron St., Chicago, IL, 60611, USA,
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196
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Pandey S, Singh S, Anang V, Bhatt AN, Natarajan K, Dwarakanath BS. Pattern Recognition Receptors in Cancer Progression and Metastasis. CANCER GROWTH AND METASTASIS 2015; 8:25-34. [PMID: 26279628 PMCID: PMC4514171 DOI: 10.4137/cgm.s24314] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 06/29/2015] [Accepted: 07/01/2015] [Indexed: 02/07/2023]
Abstract
The innate immune system is an integral component of the inflammatory response to pathophysiological stimuli. Toll-like receptors (TLRs) and inflammasomes are the major sensors and pattern recognition receptors (PRRs) of the innate immune system that activate stimulus (signal)-specific pro-inflammatory responses. Chronic activation of PRRs has been found to be associated with the aggressiveness of various cancers and poor prognosis. Involvement of PRRs was earlier considered to be limited to infection- and injury-driven carcinogenesis, where they are activated by pathogenic ligands. With the recognition of damage-associated molecular patterns (DAMPs) as ligands of PRRs, the role of PRRs in carcinogenesis has also been implicated in other non-pathogen-driven neoplasms. Dying (apoptotic or necrotic) cells shed a plethora of DAMPs causing persistent activation of PRRs, leading to chronic inflammation and carcinogenesis. Such chronic activation of TLRs promotes tumor cell proliferation and enhances tumor cell invasion and metastasis by regulating pro-inflammatory cytokines, metalloproteinases, and integrins. Due to the decisive role of PRRs in carcinogenesis, targeting PRRs appears to be an effective cancer-preventive strategy. This review provides a brief account on the association of PRRs with various cancers and their role in carcinogenesis.
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Affiliation(s)
- Sanjay Pandey
- Institute of Nuclear Medicine and Allied Sciences, Brig. S.K. Mazumdar Road, Delhi, India. ; Dr B.R. Ambedkar Center for Biomedical Research, University of Delhi, Delhi, India
| | - Saurabh Singh
- Institute of Nuclear Medicine and Allied Sciences, Brig. S.K. Mazumdar Road, Delhi, India
| | - Vandana Anang
- Dr B.R. Ambedkar Center for Biomedical Research, University of Delhi, Delhi, India
| | - Anant N Bhatt
- Institute of Nuclear Medicine and Allied Sciences, Brig. S.K. Mazumdar Road, Delhi, India
| | - K Natarajan
- Dr B.R. Ambedkar Center for Biomedical Research, University of Delhi, Delhi, India
| | - Bilikere S Dwarakanath
- Institute of Nuclear Medicine and Allied Sciences, Brig. S.K. Mazumdar Road, Delhi, India
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197
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Eigenbrod T, Keller P, Kaiser S, Rimbach K, Dalpke AH, Helm M. Recognition of Specified RNA Modifications by the Innate Immune System. Methods Enzymol 2015; 560:73-89. [PMID: 26253966 DOI: 10.1016/bs.mie.2015.03.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Microbial nucleic acids have been described as important activators of human innate immune responses by triggering so-called pattern recognition receptors (PRRs) that are expressed on innate immune cells, including plasmacytoid dendritic cells and monocytes. Although host and microbial nucleic acids share pronounced chemical and structural similarities, they significantly differ in their posttranscriptional modification profile, allowing the host to discriminate between self and nonself. In this regard, ribose 2'-O-methylation has been discovered as suppressor of RNA-induced PRR activation. Although 2'-O-methylation occurs with higher frequencies in eukaryotic than in prokaryotic RNA, the immunosuppressive properties of 2'-O-methylated nucleotides may be misused by certain bacteria as immune evasion mechanism. In the course of identifying inhibitory RNA modifications, our groups have synthesized and comparatively analyzed a series of differentially modified RNAs, so-called modivariants, for their immune stimulatory capacities. In this chapter, we will detail the protocols for the design and synthesis of RNA modivariants by molecular cut-and-paste techniques (referred to as molecular surgery) and describe testing of their immune stimulatory properties upon transfection into peripheral blood mononuclear cells.
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Affiliation(s)
- Tatjana Eigenbrod
- Department of Infectious Diseases, Medical Microbiology and Hygiene, University of Heidelberg, Heidelberg, Germany
| | - Patrick Keller
- Institute of Pharmacy and Biochemistry, Johannes Gutenberg-University of Mainz, Mainz, Germany
| | - Steffen Kaiser
- Institute of Pharmacy and Biochemistry, Johannes Gutenberg-University of Mainz, Mainz, Germany
| | - Katharina Rimbach
- Department of Infectious Diseases, Medical Microbiology and Hygiene, University of Heidelberg, Heidelberg, Germany
| | - Alexander H Dalpke
- Department of Infectious Diseases, Medical Microbiology and Hygiene, University of Heidelberg, Heidelberg, Germany
| | - Mark Helm
- Institute of Pharmacy and Biochemistry, Johannes Gutenberg-University of Mainz, Mainz, Germany.
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198
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Innate Immunity and Biomaterials at the Nexus: Friends or Foes. BIOMED RESEARCH INTERNATIONAL 2015; 2015:342304. [PMID: 26247017 PMCID: PMC4515263 DOI: 10.1155/2015/342304] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 06/15/2015] [Accepted: 06/22/2015] [Indexed: 01/04/2023]
Abstract
Biomaterial implants are an established part of medical practice, encompassing a broad range of devices that widely differ in function and structural composition. However, one common property amongst biomaterials is the induction of the foreign body response: an acute sterile inflammatory reaction which overlaps with tissue vascularisation and remodelling and ultimately fibrotic encapsulation of the biomaterial to prevent further interaction with host tissue. Severity and clinical manifestation of the biomaterial-induced foreign body response are different for each biomaterial, with cases of incompatibility often associated with loss of function. However, unravelling the mechanisms that progress to the formation of the fibrotic capsule highlights the tightly intertwined nature of immunological responses to a seemingly noncanonical “antigen.” In this review, we detail the pathways associated with the foreign body response and describe possible mechanisms of immune involvement that can be targeted. We also discuss methods of modulating the immune response by altering the physiochemical surface properties of the biomaterial prior to implantation. Developments in these areas are reliant on reproducible and effective animal models and may allow a “combined” immunomodulatory approach of adapting surface properties of biomaterials, as well as treating key immune pathways to ultimately reduce the negative consequences of biomaterial implantation.
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199
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Eigenbrod T, Dalpke AH. Bacterial RNA: An Underestimated Stimulus for Innate Immune Responses. THE JOURNAL OF IMMUNOLOGY 2015; 195:411-8. [DOI: 10.4049/jimmunol.1500530] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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200
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Wan GX, Cao YW, Li WQ, Li YC, Zhang WJ, Li F. Associations between TLR9 polymorphisms and cancer risk: evidence from an updated meta-analysis of 25,685 subjects. Asian Pac J Cancer Prev 2015; 15:8279-85. [PMID: 25339018 DOI: 10.7314/apjcp.2014.15.19.8279] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
A meta-analysis incorporating 34 case-control studies from 19 articles involving 12,197 cases and 13,488 controls was conducted to assess the effects of three genetic variants of Toll-like receptor 9 (TLR9): rs187084, rs352140, and rs5743836. Studies on associations between TLR9 polymorphisms and cancer risk were systematically searched in electronic databases. The reported odds ratios (OR) and 95% confidence intervals (CI) were pooled to assess the strength of any associations. The results showed that the rs187084 polymorphism was significantly associated with an increased risk of cancer (CC vs TC+TT: OR=1.14, 95% CI=1.02-1.28), specifically cervical cancer (C vs T: OR=1.19, 95% CI=1.05-1.34; TC vs TT: OR=1.32, 95% CI=1.10-1.58; CC vs TT: OR=1.31, 95% CI= 1.03-1.68; CC+TC vs TT: OR=1.32, 95% CI=1.11-1.56), and that this association was significantly positive in Caucasians (CC vs. TC+TT: OR=1.18, 95% CI=1.01-1.38). The rs352140 polymorphism had a protective effect on breast cancer (GA vs GG: OR=0.77, 95% CI=0.66-0.89), whereas the rs5743836 polymorphism was likely protective for digestive system cancers (CC+TC vs TT: OR=0.81, 95% CI=0.66-0.98). In conclusion, our results suggest that the rs187084 polymorphism may be associated with an elevated cancer risk, whereas polymorphisms of rs352140 and rs5743836 may play protective roles in the development of breast and digestive system cancers, respectively. From the results of this meta-analysis further large-scale case-control studies are warranted to verify associations between TLR9 polymorphisms and cancer.
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Affiliation(s)
- Guo-Xing Wan
- Department of Pathology and the Key Laboratories for Xinjiang Endemic and Ethnic Diseases (a joint venture with the Chinese Ministry of Education), Shihezi University School of Medicine, Shihezi, Xinjiang, China E-mail :
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