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Luo X, Jean-Toussaint R, Tian Y, Balashov SV, Sacan A, Ajit SK. Small Extracellular Vesicles From Spared Nerve Injury Model and Sham Control Mice Differentially Regulate Gene Expression in Primary Microglia. THE JOURNAL OF PAIN 2023; 24:1570-1581. [PMID: 37044293 PMCID: PMC10524046 DOI: 10.1016/j.jpain.2023.03.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 03/17/2023] [Accepted: 03/29/2023] [Indexed: 04/14/2023]
Abstract
Nerve injury outcomes might be predicted by examining small extracellular vesicles (sEVs) in circulation, as their biomolecular cargo facilitates cellular communication and can alter transcriptional state and behavior of recipient cells. We found that sEVs from the serum of spared nerve injury (SNI) model male mice had 7 differentially expressed miRNAs compared to sEVs from sham-operated control mice 4 weeks postsurgery. We investigated how these sEVs alter transcription in primary cortical microglia, a crucial mediator of neuropathic pain, using RNA sequencing. While the uptake of sEVs from both SNI model and sham groups changed gene expression in microglia compared to PBS treatment, sEVs from the sham group induced a more drastic change, particularly in genes involved in immune response. This was recapitulated by increased levels of pro-inflammatory cytokines and chemokines in microglia incubated with sEVs from sham control compared to sEVs from SNI model, naïve mice, or PBS. However, treating microglia with sEVs from female mice showed that serum sEVs derived from female SNI mice but not from female sham mice induced a more pronounced microglial secretion of pro-inflammatory mediators. Our data demonstrate that the molecular changes induced by sham surgery injuring skin and muscles are reflected in circulating sEVs in male mice 4 weeks later. Thus, when using sEVs from sham mice as control in comparative mechanistic studies after nerve injury, sex of mice should be taken into consideration. PERSPECTIVE: Microglial uptake of sEVs from male sham control mice induces higher pro-inflammatory responses compared to SNI sEVs but the reverse was observed upon treatment with sEVs from female mice. Wound healing may have a long-term impact on sEVs in male mice and should be considered for comparative studies using sEVs.
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Affiliation(s)
- Xuan Luo
- Pharmacology & Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Renée Jean-Toussaint
- Pharmacology & Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Yuzhen Tian
- Pharmacology & Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Sergey V Balashov
- Microbiology & Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Ahmet Sacan
- School of Biomedical Engineering, Science & Health Systems, Drexel University, Philadelphia, Pennsylvania
| | - Seena K Ajit
- Pharmacology & Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania.
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Vappala S, Smith SA, Kizhakkedathu JN, Morrissey JH. Inhibitors of Polyphosphate and Neutrophil Extracellular Traps. Semin Thromb Hemost 2023:10.1055/s-0043-1768936. [PMID: 37192652 PMCID: PMC10651799 DOI: 10.1055/s-0043-1768936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The contact pathway of blood clotting has received intense interest in recent years as studies have linked it to thrombosis, inflammation, and innate immunity. Because the contact pathway plays little to no role in normal hemostasis, it has emerged as a potential target for safer thromboprotection, relative to currently approved antithrombotic drugs which all target the final common pathway of blood clotting. Research since the mid-2000s has identified polyphosphate, DNA, and RNA as important triggers of the contact pathway with roles in thrombosis, although these molecules also modulate blood clotting and inflammation via mechanisms other than the contact pathway of the clotting cascade. The most significant source of extracellular DNA in many disease settings is in the form of neutrophil extracellular traps (NETs), which have been shown to contribute to incidence and severity of thrombosis. This review summarizes known roles of extracellular polyphosphate and nucleic acids in thrombosis, with an emphasis on novel agents under current development that target the prothrombotic activities of polyphosphate and NETs.
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Affiliation(s)
- Sreeparna Vappala
- Department of Pathology and Laboratory Medicine; and Centre for Blood Research, Life Science Institute; University of British Columbia, Vancouver, British Columbia, Canada
| | - Stephanie A. Smith
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Jayachandran N. Kizhakkedathu
- Department of Pathology and Laboratory Medicine; and Centre for Blood Research, Life Science Institute; University of British Columbia, Vancouver, British Columbia, Canada
- Department of Chemistry; and School of Biomedical Engineering; University of British Columbia, Vancouver, British Columbia, Canada
| | - James H. Morrissey
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA
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Functions and cellular signaling by ribosomal extracellular RNA (rexRNA): Facts and hypotheses on a non-typical DAMP. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2023; 1870:119408. [PMID: 36503009 DOI: 10.1016/j.bbamcr.2022.119408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 11/07/2022] [Accepted: 11/30/2022] [Indexed: 12/13/2022]
Abstract
Upon microbial infections with the subsequent host response of innate immunity, a variety of fragmented RNA- and DNA-based "Pathogen-associated molecular patterns" (PAMPs) are recognized mainly by endosomal or cytoplasmic host cell "Pattern recognition receptors" (PRRs), particularly "Toll-like receptors" (TLRs). Concomitantly, various self-extracellular RNA species (exRNAs) are present in extracellular body fluids where they contribute to diverse physiological and homeostatic processes. In principle, such exRNAs, including the most abundant one, ribosomal exRNA (rexRNA), are designated as "Danger-associated molecular patterns" (DAMPs) and are prevented by e.g. natural modifications from uncontrolled signaling via TLRs to avoid hyper-inflammatory responses or autoimmunity. Upon cellular stress or tissue damage/necrosis, the levels and composition of released self-exRNA species, either in free form, in complex with proteins or in association with extracellular vesicles (EVs), can change considerably. Among the self-exRNAs, rexRNA is considered as a non-typical DAMP, since it may induce inflammatory responses by cell membrane receptors, both in the absence or presence of PAMPs. Yet, its mode of receptor activation to mount inflammatory responses remains obscure. RexRNA also serves as a universal damaging factor in cardiovascular and other diseases independent of PRRs. In general, RNase1 provides a profound antagonist in these pathologies and in rexRNA-mediated inflammatory cell responses. Based on the extrapolation of the here described aspects of rexRNA-biology, further activities of this molecular entity are hypothesized that may stimulate additional research in this area.
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Preissner KT, Fischer S, Deindl E. Extracellular RNA as a Versatile DAMP and Alarm Signal That Influences Leukocyte Recruitment in Inflammation and Infection. Front Cell Dev Biol 2020; 8:619221. [PMID: 33392206 PMCID: PMC7775424 DOI: 10.3389/fcell.2020.619221] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 11/30/2020] [Indexed: 12/11/2022] Open
Abstract
Upon vascular injury, tissue damage, ischemia, or microbial infection, intracellular material such as nucleic acids and histones is liberated and comes into contact with the vessel wall and circulating blood cells. Such "Danger-associated molecular patterns" (DAMPs) may thus have an enduring influence on the inflammatory defense process that involves leukocyte recruitment and wound healing reactions. While different species of extracellular RNA (exRNA), including microRNAs and long non-coding RNAs, have been implicated to influence inflammatory processes at different levels, recent in vitro and in vivo work has demonstrated a major impact of ribosomal exRNA as a prominent DAMP on various steps of leukocyte recruitment within the innate immune response. This includes the induction of vascular hyper-permeability and vasogenic edema by exRNA via the activation of the "vascular endothelial growth factor" (VEGF) receptor-2 system, as well as the recruitment of leukocytes to the inflamed endothelium, the M1-type polarization of inflammatory macrophages, or the role of exRNA as a pro-thrombotic cofactor to promote thrombosis. Beyond sterile inflammation, exRNA also augments the docking of bacteria to host cells and the subsequent microbial invasion. Moreover, upon vessel occlusion and ischemia, the shear stress-induced release of exRNA initiates arteriogenesis (i.e., formation of natural vessel bypasses) in a multistep process that resembles leukocyte recruitment. Although exRNA can be counteracted for by natural circulating RNase1, under the conditions mentioned, only the administration of exogenous, thermostable, non-toxic RNase1 provides an effective and safe therapeutic regimen for treating the damaging activities of exRNA. It remains to be investigated whether exRNA may also influence viral infections (including COVID-19), e.g., by supporting the interaction of host cells with viral particles and their subsequent invasion. In fact, as a consequence of the viral infection cycle, massive amounts of exRNA are liberated, which can provoke further tissue damage and enhance virus dissemination. Whether the application of RNase1 in this scenario may help to limit the extent of viral infections like COVID-19 and impact on leukocyte recruitment and emigration steps in immune defense in order to limit the extent of associated cardiovascular diseases remains to be studied.
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Affiliation(s)
- Klaus T. Preissner
- Department of Biochemistry, Medical School, Justus Liebig University Giessen, Giessen, Germany
- Kerckhoff-Heart-Research-Institute, Department of Cardiology, Medical School, Justus Liebig University Giessen, Giessen, Germany
| | - Silvia Fischer
- Department of Biochemistry, Medical School, Justus Liebig University Giessen, Giessen, Germany
| | - Elisabeth Deindl
- Walter-Brendel-Centre of Experimental Medicine, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, LMU Munich, Munich, Germany
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Kosgey JC, Jia L, Nyamao RM, Zhao Y, Xue T, Yang J, Fang Y, Zhang F. RNase 1, 2, 5 & 8 role in innate immunity: Strain specific antimicrobial activity. Int J Biol Macromol 2020; 160:1042-1049. [PMID: 32504708 DOI: 10.1016/j.ijbiomac.2020.06.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/31/2020] [Accepted: 06/01/2020] [Indexed: 01/26/2023]
Abstract
The increase in microbial resistance to conventional antimicrobial agents is driving research for the discovery of new antibiotics and antifungal agents. The greatest challenge in this endeavor is to find antimicrobial agents with broad antimicrobial activity and low toxicity. Antimicrobial peptides, for example, RNases, are one of the promising areas. The production of RNases increases during infection, but their role is still being explored. Whereas the enzymatic activity of RNases is well documented, their physiological function is still being investigated. This study aimed to evaluate the antimicrobial activity of RNase 1, 2, 5, and 8 against E. coli strains, S. aureus, Streptococcus thermophilus, P. aeruginosa, Candida albicans, and Candida glabrata. The results demonstrated that RNases have a strain-specific antimicrobial activity. RNase 1 had the highest antimicrobial activity compared to other RNases. All the microorganisms screened had varying levels of susceptibility to RNases, except P. aeruginosa and E. coli DR115. RNase 1 showed dose-dependent activity against C. albicans. The RNase killed Candida albicans by lowering the mitochondrial membrane potential but did not damage the cell membrane. We concluded that strain-specific antimicrobial activity is one of the physiological roles of RNases.
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Affiliation(s)
- Janet Cheruiyot Kosgey
- School of Biological and Life Sciences, The Technical University of Kenya, 52428-00200, Kenya; Department of Microbiology, WU Lien-Teh Institute, Harbin Medical University, Harbin 150086, China
| | - Lina Jia
- Department of Microbiology, WU Lien-Teh Institute, Harbin Medical University, Harbin 150086, China
| | - Rose Magoma Nyamao
- Department of Microbiology, WU Lien-Teh Institute, Harbin Medical University, Harbin 150086, China; School of Medicine, Kenyatta University, 43844, 00100, Kenya
| | - Yi Zhao
- Department of Microbiology, WU Lien-Teh Institute, Harbin Medical University, Harbin 150086, China
| | - Teng Xue
- Department of Microbiology, WU Lien-Teh Institute, Harbin Medical University, Harbin 150086, China
| | - Jianxun Yang
- Department of Microbiology, WU Lien-Teh Institute, Harbin Medical University, Harbin 150086, China; Department of Dermatology, The 2nd Hospital of Harbin Medical University, Harbin 150086, China
| | - Yong Fang
- Department of Microbiology, WU Lien-Teh Institute, Harbin Medical University, Harbin 150086, China
| | - Fengmin Zhang
- Department of Microbiology, WU Lien-Teh Institute, Harbin Medical University, Harbin 150086, China.
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Dufourd T, Robil N, Mallet D, Carcenac C, Boulet S, Brishoual S, Rabois E, Houeto JL, de la Grange P, Carnicella S. Plasma or serum? A qualitative study on rodents and humans using high-throughput microRNA sequencing for circulating biomarkers. Biol Methods Protoc 2019; 4:bpz006. [PMID: 32395624 PMCID: PMC7200924 DOI: 10.1093/biomethods/bpz006] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 04/26/2019] [Accepted: 05/24/2019] [Indexed: 02/06/2023] Open
Abstract
microRNAs are small non-coding RNAs gaining interest for their potential roles as reliable biomarkers for the diagnosis and therapeutics of numerous pathologies, ranging from cancer to neurodegenerative or psychiatric disorders. Indeed, microRNAs are present in various accessible biofluids, including peripheral blood, and specific dysregulation of their expression may be associated with these different pathological conditions. microRNAs can be isolated from plasma or serum for sequencing with commercial kits. However, these two biofluids might exhibit some differences in their microRNA contents, due notably to the coagulation process occurring during serum collection. It remains unclear from previous studies and commercial recommendations which blood fraction is preferable. Because of the small amount of circulating microRNAs in a given blood volume, this question appears crucial for qualitative and quantitative optimization of microRNA profiling, especially in animal models used for investigating the pathophysiological relevancy of this approach. We therefore evaluated the efficiency of RNA isolation and microRNA levels from plasma and sera isolated from rats and humans, with a widely used extraction kit (QIAGEN miRNeasy), and assessed microRNA quality and quantity with high-throughput sequencing. Fewer reads with length corresponding to non-miRNAs sequences were observed in plasma than in serum, both from rats and humans. Moreover, rat plasma produced twice as many aligned reads compared to sera, as well as more aligned reads corresponding to microRNAs (84.6% against 38.7%), differences that were not find in human samples. Our results, therefore, clearly indicate that plasma should be preferred for miRNA investigations, particularly for translational studies.
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Affiliation(s)
- Thibault Dufourd
- Inserm, U1216, University Grenoble Alpes, Grenoble Institut des Neurosciences, 38000 Grenoble, France
| | | | - David Mallet
- Inserm, U1216, University Grenoble Alpes, Grenoble Institut des Neurosciences, 38000 Grenoble, France
| | - Carole Carcenac
- Inserm, U1216, University Grenoble Alpes, Grenoble Institut des Neurosciences, 38000 Grenoble, France
| | - Sabrina Boulet
- Inserm, U1216, University Grenoble Alpes, Grenoble Institut des Neurosciences, 38000 Grenoble, France
| | | | | | | | | | - Sebastien Carnicella
- Inserm, U1216, University Grenoble Alpes, Grenoble Institut des Neurosciences, 38000 Grenoble, France
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Li S, Chen L, Wang G, Xu L, Hou S, Chen Z, Xu X, Wang X, Liu F, Du YZ. Anti-ICAM-1 antibody-modified nanostructured lipid carriers: a pulmonary vascular endothelium-targeted device for acute lung injury therapy. J Nanobiotechnology 2018; 16:105. [PMID: 30594254 PMCID: PMC6311082 DOI: 10.1186/s12951-018-0431-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 12/10/2018] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Acute lung injury (ALI) is a life-threatening clinical syndrome without effective treatment. Targeting delivery of glucocorticoid to lung shows potential efficacy for ALI based on their anti-inflammatory and anti-fibrotic properties, breaking through their clinical application limitation due to systemic side effects. This work was aimed to establish lung-targeted dexamethasone (DEX) loaded nanostructured lipid carriers (NLCs) with opposite surface charge and investigate their therapeutic effects on lipopolysaccharide (LPS)-induced ALI mice. RESULTS The diameter of anionic anti-intercellular adhesion molecule 1 (anti-ICAM-1) antibody-conjugated DEX-loaded NLCs (ICAM/DEX/NLCs) and the cationic ones with octadecylamine (ODA) modification (ICAM/DEX/ODA-NLCs) was about 249.9 and 235.9 nm. The zeta potential of ICAM/DEX/NLCs and ICAM/DEX/ODA-NLCs was about - 30.3 and 37.4 mV, respectively. Relative to the non-targeted control and ICAM/DEX/ODA-NLCs, ICAM/DEX/NLCs exhibited higher in vitro cellular uptake in LPS-activated human vascular endothelial cell line EAhy926 after CAM-mediated endocytosis, and stronger in vivo pulmonary distribution in the ALI model mice. In vivo i.v. administration of ICAM/DEX/NLCs significantly attenuated pulmonary inflammatory cells infiltration, and the production of pro-inflammatory cytokine TNF-α and IL-6 in ALI mice. H&E stain also revealed positive histological improvements by ICAM/DEX/NLCs. CONCLUSIONS ICAM/DEX/NLCs may represent a potential pulmonary endothelium targeted device, which facilitate translation of DEX into clinical ALI treatment.
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Affiliation(s)
- Shujuan Li
- Department of Pharmacy, Zhejiang Pharmaceutical College, Ningbo, 315100, Zhejiang, China
| | - Li Chen
- Institute of Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, People's Republic of China.,Department of Pharmacy, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China
| | - Guokang Wang
- Department of Pharmacy, Zhejiang Pharmaceutical College, Ningbo, 315100, Zhejiang, China
| | - Lexing Xu
- Department of Pharmacy, Zhejiang Pharmaceutical College, Ningbo, 315100, Zhejiang, China
| | - Shanshan Hou
- Department of Pharmacy, Zhejiang Pharmaceutical College, Ningbo, 315100, Zhejiang, China
| | - Ziwei Chen
- Department of Pharmacy, Zhejiang Pharmaceutical College, Ningbo, 315100, Zhejiang, China
| | - Xiaoling Xu
- Institute of Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, People's Republic of China
| | - Xiaojuan Wang
- Department of Pharmacy, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China
| | - Fuhe Liu
- Department of Pharmacy, Zhejiang Pharmaceutical College, Ningbo, 315100, Zhejiang, China.
| | - Yong-Zhong Du
- Institute of Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, People's Republic of China.
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Combined delivery of angiopoietin-1 gene and simvastatin mediated by anti-intercellular adhesion molecule-1 antibody-conjugated ternary nanoparticles for acute lung injury therapy. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2018; 15:25-36. [PMID: 30193816 DOI: 10.1016/j.nano.2018.08.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Revised: 07/10/2018] [Accepted: 08/19/2018] [Indexed: 01/02/2023]
Abstract
Effective treatment for acute lung injury (ALI) is in high demand. Lung-targeted ternary nanoparticles containing anti-intercellular adhesion molecule-1 (ICAM-1) antibody-conjugated simvastatin-loaded nanostructured lipid carrier (ICAM/NLC), protamine (Pro), and angiopoietin-1 (Ang-1) gene (ICAM-NLC/Pro/Ang) were developed for ALI therapy. The ternary nanoparticles with different weight ratios of ICAM-NLC to Ang-1 gene were prepared via charge interaction. The anti-ICAM-1 antibody-conjugated ternary nanoparticles exhibited higher cellular uptake and transfection efficiency (from 26.7% to 30.9%) in human vascular endothelial cell line EAhy926 than the non-targeted control. The largest size of ICAM-NLC/Pro/Ang (357.1 nm) was employed for further study, which significantly up-regulated in vitro and in vivo Ang-1 protein expression. In vivo i.v. administration of ICAM-NLC/Pro/Ang (357.1 nm) significantly attenuated pulmonary TNF-α and IL-6 levels, inflammatory cell infiltration, and led to positive histological improvements in lipopolysaccharide-induced ALI mice. Collectively, the ICAM-NLC/Pro/Ang that co-delivered simvastatin and Ang-1 gene may represent a potential treatment modality for ALI.
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Noll F, Behnke J, Leiting S, Troidl K, Alves GT, Müller-Redetzky H, Preissner KT, Fischer S. Self-extracellular RNA acts in synergy with exogenous danger signals to promote inflammation. PLoS One 2017; 12:e0190002. [PMID: 29261777 PMCID: PMC5738100 DOI: 10.1371/journal.pone.0190002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 12/06/2017] [Indexed: 01/05/2023] Open
Abstract
Self-extracellular RNA (eRNA), released from stressed or injured cells upon various pathological situations such as ischemia-reperfusion-injury, has been shown to act as an alarmin by inducing procoagulatory and proinflammatory responses. In particular, M1-polarization of macrophages by eRNA resulted in the expression and release of a variety of cytokines, including tumor necrosis factor (TNF)-α or interleukin-6 (IL-6). The present study now investigates in which way self-eRNA may influence the response of macrophages towards various Toll-like receptor (TLR)-agonists. Isolated agonists of TLR2 (Pam2CSK4), TLR3 (PolyIC), TLR4 (LPS), or TLR7 (R848) induced the release of TNF-α in a concentration-dependent manner in murine macrophages, differentiated from bone marrow-derived stem cells by mouse colony stimulating factor. Here, the presence of eRNA shifted the dose-response curve for Pam2CSK4 (Pam) considerably to the left, indicating that eRNA synergistically enhanced the cytokine liberation from macrophages even at very low Pam-levels. The synergistic activation of TLR2 by eRNA/Pam was duplicated by other TLR2-agonists such as FSL-1 or Pam3CSK4. In contrast, for TLR4-agonists such as LPS a synergistic effect of eRNA was much weaker, and was not existent for TLR3-, or TLR7-agonists. The synergistic eRNA/Pam action was dependent on the NFκB-signaling pathway as well as on p38MAP- and MEK1/ERK-kinases and was prevented by predigestion of eRNA with RNase1 or by antibodies against TLR2. Thus, the presence of self-eRNA as alarming molecule sensitizes innate immune responses towards pathogen-associated molecular patterns (PAMPs) in a synergistic way and may thereby contribute to the differentiated outcome of inflammatory responses.
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Affiliation(s)
- Frederik Noll
- Institute of Biochemistry, Medical School, Justus-Liebig-University, Giessen, Germany
| | - Jonas Behnke
- Institute of Biochemistry, Medical School, Justus-Liebig-University, Giessen, Germany
| | - Silke Leiting
- Institute of Biochemistry, Medical School, Justus-Liebig-University, Giessen, Germany
| | - Kerstin Troidl
- Max-Planck-Instiute for Heart and Lung research, Bad Nauheim, Germany
- Department of Vascular and Endovascular Surgery, University Hospital Frankfurt, Frankfurt, Germany
| | - Gustavo Teixeira Alves
- Department of Infectious Diseases and Pulmonary Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Holger Müller-Redetzky
- Department of Infectious Diseases and Pulmonary Medicine, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Klaus T. Preissner
- Institute of Biochemistry, Medical School, Justus-Liebig-University, Giessen, Germany
| | - Silvia Fischer
- Institute of Biochemistry, Medical School, Justus-Liebig-University, Giessen, Germany
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