1
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Liu C, Wei W, Huang Y, Fu P, Zhang L, Zhao Y. Metabolic reprogramming in septic acute kidney injury: pathogenesis and therapeutic implications. Metabolism 2024; 158:155974. [PMID: 38996912 DOI: 10.1016/j.metabol.2024.155974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 07/06/2024] [Accepted: 07/09/2024] [Indexed: 07/14/2024]
Abstract
Acute kidney injury (AKI) is a frequent and severe complication of sepsis and is characterized by significant mortality and morbidity. However, the pathogenesis of septic acute kidney injury (S-AKI) remains elusive. Metabolic reprogramming, which was originally referred to as the Warburg effect in cancer, is strongly related to S-AKI. At the onset of sepsis, both inflammatory cells and renal parenchymal cells, such as macrophages, neutrophils and renal tubular epithelial cells, undergo metabolic shifts toward aerobic glycolysis to amplify proinflammatory responses and fortify cellular resilience to septic stimuli. As the disease progresses, these cells revert to oxidative phosphorylation, thus promoting anti-inflammatory reactions and enhancing functional restoration. Alterations in mitochondrial dynamics and metabolic reprogramming are central to the energetic changes that occur during S-AKI. In this review, we summarize the current understanding of the pathogenesis of metabolic reprogramming in S-AKI, with a focus on each cell type involved. By identifying relevant key regulatory factors, we also explored potential metabolic reprogramming-related therapeutic targets for the management of S-AKI.
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Affiliation(s)
- Caihong Liu
- Department of Nephrology, Institute of Kidney Diseases, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Wei Wei
- Department of Nephrology, Institute of Kidney Diseases, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Yongxiu Huang
- Department of Nephrology, Institute of Kidney Diseases, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Ping Fu
- Department of Nephrology, Institute of Kidney Diseases, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Ling Zhang
- Department of Nephrology, Institute of Kidney Diseases, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Yuliang Zhao
- Department of Nephrology, Institute of Kidney Diseases, West China Hospital of Sichuan University, Chengdu 610041, China.
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2
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Gao S, Mao C, Yuan S, Quan Y, Jin W, Shen Y, Zhang X, Wang Y, Yi L, Wang Y. AI-2 quorum sensing-induced galactose metabolism activation in Streptococcus suis enhances capsular polysaccharide-associated virulence. Vet Res 2024; 55:80. [PMID: 38886823 PMCID: PMC11184709 DOI: 10.1186/s13567-024-01335-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Accepted: 05/29/2024] [Indexed: 06/20/2024] Open
Abstract
Bacteria utilize intercellular communication to orchestrate essential cellular processes, adapt to environmental changes, develop antibiotic tolerance, and enhance virulence. This communication, known as quorum sensing (QS), is mediated by the exchange of small signalling molecules called autoinducers. AI-2 QS, regulated by the metabolic enzyme LuxS (S-ribosylhomocysteine lyase), acts as a universal intercellular communication mechanism across gram-positive and gram-negative bacteria and is crucial for diverse bacterial processes. In this study, we demonstrated that in Streptococcus suis (S. suis), a notable zoonotic pathogen, AI-2 QS enhances galactose utilization, upregulates the Leloir pathway for capsular polysaccharide (CPS) precursor production, and boosts CPS synthesis, leading to increased resistance to macrophage phagocytosis. Additionally, our molecular docking and dynamics simulations suggest that, similar to S. pneumoniae, FruA, a fructose-specific phosphoenolpyruvate phosphotransferase system prevalent in gram-positive pathogens, may also function as an AI-2 membrane surface receptor in S. suis. In conclusion, our study demonstrated the significance of AI-2 in the synthesis of galactose metabolism-dependent CPS in S. suis. Additionally, we conducted a preliminary analysis of the potential role of FruA as a membrane surface receptor for S. suis AI-2.
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Affiliation(s)
- Shuji Gao
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- College of Life Science, Luoyang Normal University, Luoyang, 471934, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Chenlong Mao
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Shuo Yuan
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Yingying Quan
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Wenjie Jin
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Yamin Shen
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Xiaoling Zhang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Yuxin Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Li Yi
- College of Life Science, Luoyang Normal University, Luoyang, 471934, China.
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China.
| | - Yang Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China.
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China.
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3
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Gao S, Jin W, Quan Y, Li Y, Shen Y, Yuan S, Yi L, Wang Y, Wang Y. Bacterial capsules: Occurrence, mechanism, and function. NPJ Biofilms Microbiomes 2024; 10:21. [PMID: 38480745 PMCID: PMC10937973 DOI: 10.1038/s41522-024-00497-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 03/05/2024] [Indexed: 03/17/2024] Open
Abstract
In environments characterized by extended multi-stress conditions, pathogens develop a variety of immune escape mechanisms to enhance their ability to infect the host. The capsules, polymers that bacteria secrete near their cell wall, participates in numerous bacterial life processes and plays a crucial role in resisting host immune attacks and adapting to their niche. Here, we discuss the relationship between capsules and bacterial virulence, summarizing the molecular mechanisms of capsular regulation and pathogenesis to provide new insights into the research on the pathogenesis of pathogenic bacteria.
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Affiliation(s)
- Shuji Gao
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Wenjie Jin
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Yingying Quan
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Yue Li
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Yamin Shen
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Shuo Yuan
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Li Yi
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
- College of Life Science, Luoyang Normal University, Luoyang, 471934, China
| | - Yuxin Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China.
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China.
| | - Yang Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China.
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China.
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Jessop F, Schwarz B, Bohrnsen E, Bosio CM. Route of Francisella tularensis infection informs spatiotemporal metabolic reprogramming and inflammation in mice. PLoS One 2023; 18:e0293450. [PMID: 37883420 PMCID: PMC10602361 DOI: 10.1371/journal.pone.0293450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 10/12/2023] [Indexed: 10/28/2023] Open
Abstract
Route of exposure to pathogens can inform divergent disease pathogenesis and mortality rates. However, the features that contribute to these differences are not well established. Host metabolism has emerged as a critical element governing susceptibility and the metabolism of tissue exposure sites are unique. Therefore, specific metabolic niches may contribute to the course and outcome of infection depending on route of infection. In the current study, we utilized a combination of imaging and systems metabolomics to map the spatiotemporal dynamics of the host response to intranasal (i.n.) or intradermal (i.d.) infection of mice using the bacterium Francisella tularensis subsp tularensis (FTT). FTT causes lethal disease through these infection routes with similar inoculation doses and replication kinetics, which allowed for isolation of host outcomes independent of bacterial burden. We observed metabolic modifications that were both route dependent and independent. Specifically, i.d. infection resulted in early metabolic reprogramming at the site of infection and draining lymph nodes, whereas the lungs and associated draining lymph nodes were refractory to metabolic reprogramming following i.n. infection. Irrespective of exposure route, FTT promoted metabolic changes in systemic organs prior to colonization, and caused massive dysregulation of host metabolism in these tissues prior to onset of morbidity. Preconditioning infection sites towards a more glycolytic and pro-inflammatory state prior to infection exacerbated FTT replication within the lungs but not intradermal tissue. This enhancement of replication in the lungs was associated with the ability of FTT to limit redox imbalance and alter the pentose phosphate pathway. Together, these studies identify central metabolic features of the lung and dermal compartments that contribute to disease progression and identify potential tissue specific targets that may be exploited for novel therapeutic approaches.
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Affiliation(s)
- Forrest Jessop
- Rocky Mountain Laboratories, NIAID, Hamilton, MT, United States of America
| | - Benjamin Schwarz
- Rocky Mountain Laboratories, NIAID, Hamilton, MT, United States of America
| | - Eric Bohrnsen
- Rocky Mountain Laboratories, NIAID, Hamilton, MT, United States of America
| | - Catharine M. Bosio
- Rocky Mountain Laboratories, NIAID, Hamilton, MT, United States of America
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5
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Abstract
Ubiquitination is a posttranslational modification that regulates a multitude of cellular functions. Pathogens, such as bacteria and viruses, have evolved sophisticated mechanisms that evade or counteract ubiquitin-dependent host responses, or even exploit the ubiquitin system to their own advantage. This is largely done by numerous pathogen virulence factors that encode E3 ligases and deubiquitinases, which are often used as weapons in pathogen-host cell interactions. Moreover, upon pathogen attack, host cellular signaling networks undergo major ubiquitin-dependent changes to protect the host cell, including coordination of innate immunity, remodeling of cellular organelles, reorganization of the cytoskeleton, and reprogramming of metabolic pathways to restrict growth of the pathogen. Here we provide mechanistic insights into ubiquitin regulation of host-pathogen interactions and how it affects bacterial and viral pathogenesis and the organization and response of the host cell.
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Affiliation(s)
- Rukmini Mukherjee
- Institute of Biochemistry II, Faculty of Medicine, Goethe University, Frankfurt, Germany; .,Buchmann Institute for Molecular Life Sciences, Goethe University, Frankfurt, Germany.,Max Planck Institute of Biophysics, Frankfurt, Germany
| | - Ivan Dikic
- Institute of Biochemistry II, Faculty of Medicine, Goethe University, Frankfurt, Germany; .,Buchmann Institute for Molecular Life Sciences, Goethe University, Frankfurt, Germany.,Max Planck Institute of Biophysics, Frankfurt, Germany.,Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Branch Translational Medicine and Pharmacology, Frankfurt, Germany
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6
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Mohammadi N, Lindgren H, Yamamoto M, Martin A, Henry T, Sjöstedt A. Macrophages Demonstrate Guanylate-Binding Protein-Dependent and Bacterial Strain-Dependent Responses to Francisella tularensis. Front Cell Infect Microbiol 2022; 11:784101. [PMID: 35004352 PMCID: PMC8738097 DOI: 10.3389/fcimb.2021.784101] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 12/09/2021] [Indexed: 11/13/2022] Open
Abstract
Francisella tularensis is a facultative intracellular bacterium and the etiological agent of tularemia, a zoonotic disease. Infection of monocytic cells by F. tularensis can be controlled after activation with IFN-γ; however, the molecular mechanisms whereby the control is executed are incompletely understood. Recently, a key role has been attributed to the Guanylate-binding proteins (GBPs), interferon-inducible proteins involved in the cell-specific immunity against various intracellular pathogens. Here, we assessed the responses of bone marrow-derived murine macrophages (BMDM) and GBP-deficient BMDM to F. tularensis strains of variable virulence; the highly virulent SCHU S4 strain, the human live vaccine strain (LVS), or the widely used surrogate for F. tularensis, the low virulent F. novicida. Each of the strains multiplied rapidly in BMDM, but after addition of IFN-γ, significant GBP-dependent control of infection was observed for the LVS and F. novicida strains, whereas there was no control of the SCHU S4 infection. However, no differences in GBP transcription or translation were observed in the infected cell cultures. During co-infection with F. novicida and SCHU S4, significant control of both strains was observed. Patterns of 18 cytokines were very distinct between infected cell cultures and high levels were observed for almost all cytokines in F. novicida-infected cultures and very low levels in SCHU S4-infected cultures, whereas levels in co-infected cultures for a majority of cytokines showed intermediate levels, or levels similar to those of F. novicida-infected cultures. We conclude that the control of BMDM infection with F. tularensis LVS or F. novicida is GBP-dependent, whereas SCHU S4 was only controlled during co-infection. Since expression of GBP was similar regardless of infecting agent, the findings imply that SCHU S4 has an inherent ability to evade the GBP-dependent anti-bacterial mechanisms.
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Affiliation(s)
- Nasibeh Mohammadi
- Department of Clinical Microbiology and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
| | - Helena Lindgren
- Department of Clinical Microbiology and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
| | - Masahiro Yamamoto
- Department of Immunoparasitology, Research Institute for Microbial Diseases, Osaka, Japan
| | - Amandine Martin
- Inserm, U1111, Centre International de Recherche en Infectiologie, Lyon, France
| | - Thomas Henry
- Inserm, U1111, Centre International de Recherche en Infectiologie, Lyon, France
| | - Anders Sjöstedt
- Department of Clinical Microbiology and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
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7
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Stabilization but no functional influence of HIF-1α expression in the intestinal epithelium during Salmonella Typhimurium infection. Infect Immun 2022; 90:e0022221. [PMID: 34978927 DOI: 10.1128/iai.00222-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The hypoxia-inducible transcription factor 1 (HIF-1) has been shown to enhance microbial killing and to ameliorate the course of bacterial infections. While the impact of HIF-1 on inflammatory diseases of the gut has been studied intensively, its function in bacterial infections of the gastrointestinal tract remains largely elusive. With the help of a publicly available gene expression data set, we could infer significant activation of HIF-1 after oral infection of mice with Salmonella Typhimurium. Immunohistochemistry and western blot analysis confirmed marked HIF-1α protein stabilization, especially in the intestinal epithelium. This prompted us to analyze conditional Hif1a-deficient mice to examine cell type-specific functions of HIF-1 in this model. Our results demonstrate enhanced non-canonical induction of HIF-1 activity upon Salmonella infection in the intestinal epithelium as well as in macrophages. Surprisingly, Hif1a deletion in intestinal epithelial cells did not impact on inflammatory gene expression, bacterial spread or disease outcome. In contrast, Hif1a deletion in myeloid cells enhanced intestinal Cxcl2 expression and reduced the cecal Salmonella load. In vitro, HIF-1α-deficient macrophages showed an overall impaired transcription of mRNA encoding pro-inflammatory factors, however, intracellular survival of Salmonella was not impacted by HIF-1α deficiency.
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8
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Liu D, Sun W, Zhang D, Yu Z, Qin W, Liu Y, Zhang K, Yin J. Long noncoding RNA GSEC promotes neutrophil inflammatory activation by supporting PFKFB3-involved glycolytic metabolism in sepsis. Cell Death Dis 2021; 12:1157. [PMID: 34907156 PMCID: PMC8671582 DOI: 10.1038/s41419-021-04428-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 11/03/2021] [Accepted: 11/17/2021] [Indexed: 12/18/2022]
Abstract
Metabolic reprogramming is a hallmark of neutrophil activation in sepsis. LncRNAs play important roles in manipulating cell metabolism; however, their specific involvement in neutrophil activation in sepsis remains unclear. Here we found that 11 lncRNAs and 105 mRNAs were differentially expressed in three transcriptome datasets (GSE13904, GSE28750, and GSE64457) of gene expression in blood leukocytes and neutrophils of septic patients and healthy volunteers. After Gene Ontology biological process analysis and lncRNA-mRNA pathway network construction, we noticed that GSEC lncRNA and PFKFB3 were co-expressed and associated with enhanced glycolytic metabolism. Our clinical observations confirmed the expression patterns of GSEC lncRNA and PFKFB3 genes in neutrophils in septic patients. Performing in vitro experiments, we found that the expression of GSEC lncRNA and PFKFB3 was increased when neutrophils were treated with inflammatory stimuli. Knockdown and overexpression experiments showed that GSEC lncRNA was essential for mediating PFKFB3 mRNA expression and stability in neutrophil-like dHL-60 cells. In addition, we found that GSEC lncRNA-induced PFKFB3 expression was essential for mediating dHL-60 cell inflammatory cytokine expression. Performing mechanistic experiments, we found that glycolytic metabolism with PFKFB3 involvement supported inflammatory cytokine expression. In summary, our study uncovers a mechanism by which GSEC lncRNA promotes neutrophil inflammatory activation in sepsis by supporting glycolytic metabolism with PFKFB3.
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Affiliation(s)
- Dadong Liu
- Department of Critical Care Medicine, Affiliated Hospital of Jiangsu University, Zhenjiang, China
| | - Wen Sun
- Department of Critical Care Medicine, Jurong Hospital Affiliated to Jiangsu University, Zhenjiang, China
| | - Danying Zhang
- Department of Laboratory Medicine, Affiliated People's Hospital of Jiangsu University, Zhenjiang, China
| | - Zongying Yu
- Department of Electrocardiograph, The No. 4 Affiliated Hospital of Jiangsu University, Zhenjiang, China
| | - Weiting Qin
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, Shanghai, China
| | - Yishu Liu
- Department of Gastrointestinal Surgery, Affiliated Hospital of Jiangsu University, Zhenjiang, China
| | - Kai Zhang
- Department of Otorhinolaryngology and Head and Neck Surgery, Affiliated Hospital of Jiangsu University, Zhenjiang, China.
| | - Jiangtao Yin
- Department of Critical Care Medicine, Affiliated Hospital of Jiangsu University, Zhenjiang, China.
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9
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Wang J, Ma S, Li W, Wang X, Huang D, Jiang L, Feng L. Salmonella enterica Serovar Typhi Induces Host Metabolic Reprogramming to Increase Glucose Availability for Intracellular Replication. Int J Mol Sci 2021; 22:ijms221810003. [PMID: 34576166 PMCID: PMC8467381 DOI: 10.3390/ijms221810003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/13/2021] [Accepted: 09/14/2021] [Indexed: 11/18/2022] Open
Abstract
Salmonella enterica serovar Typhi (S. Typhi) is a human-limited intracellular pathogen and the cause of typhoid fever, a severe systemic disease. Pathogen–host interaction at the metabolic level affects the pathogenicity of intracellular pathogens, but it remains unclear how S. Typhi infection influences host metabolism for its own benefit. Herein, using metabolomics and transcriptomics analyses, combined with in vitro and in vivo infection assays, we investigated metabolic responses in human macrophages during S. Typhi infection, and the impact of these responses on S. Typhi intracellular replication and systemic pathogenicity. We observed increased glucose content, higher rates of glucose uptake and glycolysis, and decreased oxidative phosphorylation in S. Typhi-infected human primary macrophages. Replication in human macrophages and the bacterial burden in systemic organs of humanized mice were reduced by either the inhibition of host glucose uptake or a mutation of the bacterial glucose uptake system, indicating that S. Typhi utilizes host-derived glucose to enhance intracellular replication and virulence. Thus, S. Typhi promotes its pathogenicity by inducing metabolic changes in host macrophages and utilizing the glucose that subsequently accumulates as a nutrient for intracellular replication. Our findings provide the first metabolic signature of S. Typhi-infected host cells and identifies a new strategy utilized by S. Typhi for intracellular replication.
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Affiliation(s)
- Jingting Wang
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin 300457, China; (J.W.); (S.M.); (W.L.); (X.W.); (D.H.)
- Tianjin Key Laboratory of Microbial Functional Genomics, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin 300457, China
| | - Shuai Ma
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin 300457, China; (J.W.); (S.M.); (W.L.); (X.W.); (D.H.)
- Tianjin Key Laboratory of Microbial Functional Genomics, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin 300457, China
| | - Wanwu Li
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin 300457, China; (J.W.); (S.M.); (W.L.); (X.W.); (D.H.)
- Tianjin Key Laboratory of Microbial Functional Genomics, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin 300457, China
| | - Xinyue Wang
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin 300457, China; (J.W.); (S.M.); (W.L.); (X.W.); (D.H.)
- Tianjin Key Laboratory of Microbial Functional Genomics, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin 300457, China
| | - Di Huang
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin 300457, China; (J.W.); (S.M.); (W.L.); (X.W.); (D.H.)
- Tianjin Key Laboratory of Microbial Functional Genomics, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin 300457, China
| | - Lingyan Jiang
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin 300457, China; (J.W.); (S.M.); (W.L.); (X.W.); (D.H.)
- Tianjin Key Laboratory of Microbial Functional Genomics, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin 300457, China
- Correspondence: (L.J.); (L.F.)
| | - Lu Feng
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin 300457, China; (J.W.); (S.M.); (W.L.); (X.W.); (D.H.)
- Tianjin Key Laboratory of Microbial Functional Genomics, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin 300457, China
- Correspondence: (L.J.); (L.F.)
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10
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Choudhuri S, Chowdhury IH, Garg NJ. Mitochondrial Regulation of Macrophage Response Against Pathogens. Front Immunol 2021; 11:622602. [PMID: 33679710 PMCID: PMC7925834 DOI: 10.3389/fimmu.2020.622602] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 12/29/2020] [Indexed: 12/18/2022] Open
Abstract
Innate immune cells play the first line of defense against pathogens. Phagocytosis or invasion by pathogens can affect mitochondrial metabolism in macrophages by diverse mechanisms and shape the macrophage response (proinflammatory vs. immunomodulatory) against pathogens. Besides β-nicotinamide adenine dinucleotide 2'-phosphate, reduced (NADPH) oxidase, mitochondrial electron transport chain complexes release superoxide for direct killing of the pathogen. Mitochondria that are injured are removed by mitophagy, and this process can be critical for regulating macrophage activation. For example, impaired mitophagy can result in cytosolic leakage of mitochondrial DNA (mtDNA) that can lead to activation of cGAS-STING signaling pathway of macrophage proinflammatory response. In this review, we will discuss how metabolism, mtDNA, mitophagy, and cGAS-STING pathway shape the macrophage response to infectious agents.
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Affiliation(s)
- Subhadip Choudhuri
- Department of Microbiology and Immunology, University of Texas Medical Branch (UTMB), Galveston, TX, United States
| | - Imran Hussain Chowdhury
- Department of Microbiology and Immunology, University of Texas Medical Branch (UTMB), Galveston, TX, United States
| | - Nisha Jain Garg
- Department of Microbiology and Immunology, University of Texas Medical Branch (UTMB), Galveston, TX, United States
- Institute for Human Infections and Immunity, UTMB, Galveston, TX, United States
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11
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Jiang L, Wang P, Song X, Zhang H, Ma S, Wang J, Li W, Lv R, Liu X, Ma S, Yan J, Zhou H, Huang D, Cheng Z, Yang C, Feng L, Wang L. Salmonella Typhimurium reprograms macrophage metabolism via T3SS effector SopE2 to promote intracellular replication and virulence. Nat Commun 2021; 12:879. [PMID: 33563986 PMCID: PMC7873081 DOI: 10.1038/s41467-021-21186-4] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 01/11/2021] [Indexed: 12/14/2022] Open
Abstract
Salmonella Typhimurium establishes systemic infection by replicating in host macrophages. Here we show that macrophages infected with S. Typhimurium exhibit upregulated glycolysis and decreased serine synthesis, leading to accumulation of glycolytic intermediates. The effects on serine synthesis are mediated by bacterial protein SopE2, a type III secretion system (T3SS) effector encoded in pathogenicity island SPI-1. The changes in host metabolism promote intracellular replication of S. Typhimurium via two mechanisms: decreased glucose levels lead to upregulated bacterial uptake of 2- and 3-phosphoglycerate and phosphoenolpyruvate (carbon sources), while increased pyruvate and lactate levels induce upregulation of another pathogenicity island, SPI-2, known to encode virulence factors. Pharmacological or genetic inhibition of host glycolysis, activation of host serine synthesis, or deletion of either the bacterial transport or signal sensor systems for those host glycolytic intermediates impairs S. Typhimurium replication or virulence. Salmonella Typhimurium establishes systemic infection by replicating in host macrophages. Here, Jiang et al. show that infected macrophages exhibit upregulated glycolysis and decreased serine synthesis, leading to accumulation of glycolytic intermediates that promote intracellular replication and virulence of S. Typhimurium.
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Affiliation(s)
- Lingyan Jiang
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China.,TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, China
| | - Peisheng Wang
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China.,TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, China
| | - Xiaorui Song
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China.,TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, China
| | - Huan Zhang
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China.,TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, China
| | - Shuangshuang Ma
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China.,TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, China
| | - Jingting Wang
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China.,TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, China
| | - Wanwu Li
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China.,TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, China
| | - Runxia Lv
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China.,TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, China
| | - Xiaoqian Liu
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China.,TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, China
| | - Shuai Ma
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China.,TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, China
| | - Jiaqi Yan
- College of Life Sciences, Nankai University, Tianjin, China
| | - Haiyan Zhou
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Di Huang
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China.,TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, China
| | - Zhihui Cheng
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China.,College of Life Sciences, Nankai University, Tianjin, China
| | - Chen Yang
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Lu Feng
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China. .,TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, China.
| | - Lei Wang
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China. .,TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, China. .,The Institute of Translational Medicine Research, Tianjin Union Medical Center, Nankai University Affiliated Hospital, Nankai University, Tianjin, China.
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12
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Jiang Q, Geng X, Warren J, Eugene Paul Cosky E, Kaura S, Stone C, Li F, Ding Y. Hypoxia Inducible Factor-1α (HIF-1α) Mediates NLRP3 Inflammasome-Dependent-Pyroptotic and Apoptotic Cell Death Following Ischemic Stroke. Neuroscience 2020; 448:126-139. [PMID: 32976985 DOI: 10.1016/j.neuroscience.2020.09.036] [Citation(s) in RCA: 110] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 09/08/2020] [Accepted: 09/15/2020] [Indexed: 12/19/2022]
Abstract
Stroke is a major cause of death and long-term disability. Recent evidence suggests that hypoxia-inducible factor 1α (HIF-1α), a transcription factor that regulates oxygen levels, plays a key role in neurological outcomes after ischemic stroke. Accordingly, we investigated the mechanism of HIF-1α on pyroptotic and apoptotic cells during ischemia/reperfusion (I/R). Adult Sprague-Dawley rats underwent 2 h of middle cerebral artery occlusion (MCAO). The rats were then exposed to 6 or 24 h of reperfusion, with or without YC-1 (HIF-1α inhibitor, 5 mg/kg). Infarct volumes, along with mRNA and protein quantities of HIF-1α, NLRP3, IL-1β, IL-18, Caspase-1, and co-localization of HIF-1α, and NLRP3, were assessed. We measured apoptotic and pyroptotic cell death, gasdermin D (GSDMD) activation and lactate dehydrogenase (LDH) activity, and the infiltration of neutrophils and macrophages after ischemic stroke. HIF-1α mRNA and NLRP3 inflammasome components were increased after 24 h of reperfusion. YC-1 significantly reduced the mRNA and protein expression of NLRP3, IL-1β, IL-18, and caspase-1; significantly decreased infarction and pyroptotic cell death after 24 h of reperfusion; attenuated the neuroinflammatory response by reducing infiltration of CD68- and MPO-positive cells after 24 h of reperfusion; and reduced apoptotic cell death following ischemic stroke. We found that HIF-1α likely regulates inflammatory responses through the NLRP3 inflammasome complex, thus influencing both apoptotic and pyroptotic cell death after stroke. These findings suggest that future investigations are needed regarding HIF-1α and its role as a potential molecular target in the treatment of acute ischemic stroke.
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Affiliation(s)
- Qian Jiang
- China-America Institute of Neuroscience, Beijing Luhe Hospital, Capital Medical University, China; Department of Neurology, Beijing Luhe Hospital, Capital Medical University, China
| | - Xiaokun Geng
- China-America Institute of Neuroscience, Beijing Luhe Hospital, Capital Medical University, China; Department of Neurology, Beijing Luhe Hospital, Capital Medical University, China; Department of Neurosurgery, Wayne State University School of Medicine, Detroit, MI, USA.
| | - Jonathan Warren
- Department of Neurosurgery, Wayne State University School of Medicine, Detroit, MI, USA
| | | | - Shawn Kaura
- Department of Neurosurgery, Wayne State University School of Medicine, Detroit, MI, USA
| | - Christopher Stone
- Department of Neurosurgery, Wayne State University School of Medicine, Detroit, MI, USA
| | - Fengwu Li
- China-America Institute of Neuroscience, Beijing Luhe Hospital, Capital Medical University, China; Department of Neurology, Beijing Luhe Hospital, Capital Medical University, China
| | - Yuchuan Ding
- Department of Neurosurgery, Wayne State University School of Medicine, Detroit, MI, USA; Department of Research & Development Center, John D. Dingell VA Medical Center, Detroit, MI, USA.
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13
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Goll JB, Li S, Edwards JL, Bosinger SE, Jensen TL, Wang Y, Hooper WF, Gelber CE, Sanders KL, Anderson EJ, Rouphael N, Natrajan MS, Johnson RA, Sanz P, Hoft D, Mulligan MJ. Transcriptomic and Metabolic Responses to a Live-Attenuated Francisella tularensis Vaccine. Vaccines (Basel) 2020; 8:vaccines8030412. [PMID: 32722194 PMCID: PMC7563297 DOI: 10.3390/vaccines8030412] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 05/29/2020] [Accepted: 06/14/2020] [Indexed: 12/15/2022] Open
Abstract
The immune response to live-attenuated Francisella tularensis vaccine and its host evasion mechanisms are incompletely understood. Using RNA-Seq and LC–MS on samples collected pre-vaccination and at days 1, 2, 7, and 14 post-vaccination, we identified differentially expressed genes in PBMCs, metabolites in serum, enriched pathways, and metabolites that correlated with T cell and B cell responses, or gene expression modules. While an early activation of interferon α/β signaling was observed, several innate immune signaling pathways including TLR, TNF, NF-κB, and NOD-like receptor signaling and key inflammatory cytokines such as Il-1α, Il-1β, and TNF typically activated following infection were suppressed. The NF-κB pathway was the most impacted and the likely route of attack. Plasma cells, immunoglobulin, and B cell signatures were evident by day 7. MHC I antigen presentation was more actively up-regulated first followed by MHC II which coincided with the emergence of humoral immune signatures. Metabolomics analysis showed that glycolysis and TCA cycle-related metabolites were perturbed including a decline in pyruvate. Correlation networks that provide hypotheses on the interplay between changes in innate immune, T cell, and B cell gene expression signatures and metabolites are provided. Results demonstrate the utility of transcriptomics and metabolomics for better understanding molecular mechanisms of vaccine response and potential host–pathogen interactions.
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Affiliation(s)
- Johannes B. Goll
- The Emmes Company, Rockville, MD 20850, USA; (J.B.G.); (T.L.J.); (W.F.H.); (C.E.G.)
| | - Shuzhao Li
- Departments of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA; (S.L.); (Y.W.)
| | - James L. Edwards
- Department of Chemistry, Saint Louis University, St Louis, MO 63103, USA; (J.L.E.); (K.L.S.)
| | - Steven E. Bosinger
- Yerkes National Primate Research Center, Secret Path, Atlanta, GA 30329, USA;
- Emory Vaccine Center, Emory University, Atlanta, GA 30322, USA; (N.R.); (M.S.N.)
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Decatur, GA 30030, USA
| | - Travis L. Jensen
- The Emmes Company, Rockville, MD 20850, USA; (J.B.G.); (T.L.J.); (W.F.H.); (C.E.G.)
| | - Yating Wang
- Departments of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA; (S.L.); (Y.W.)
| | - William F. Hooper
- The Emmes Company, Rockville, MD 20850, USA; (J.B.G.); (T.L.J.); (W.F.H.); (C.E.G.)
| | - Casey E. Gelber
- The Emmes Company, Rockville, MD 20850, USA; (J.B.G.); (T.L.J.); (W.F.H.); (C.E.G.)
| | - Katherine L. Sanders
- Department of Chemistry, Saint Louis University, St Louis, MO 63103, USA; (J.L.E.); (K.L.S.)
| | - Evan J. Anderson
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA;
- Department of Pediatrics, Emory University School of Medicine and Children’s Healthcare of Atlanta, Atlanta, GA, 30322, USA
| | - Nadine Rouphael
- Emory Vaccine Center, Emory University, Atlanta, GA 30322, USA; (N.R.); (M.S.N.)
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA;
| | - Muktha S. Natrajan
- Emory Vaccine Center, Emory University, Atlanta, GA 30322, USA; (N.R.); (M.S.N.)
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA;
| | - Robert A. Johnson
- Biomedical Advanced Research and Development Authority, U. S. Department of Health and Human Services, Washington, DC 20201, USA;
| | - Patrick Sanz
- Division of Microbiology and Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20892, USA;
| | - Daniel Hoft
- Division of Infectious Diseases, Allergy and Immunology, Saint Louis University Health Sciences Center, St. Louis, MO 63104, USA;
| | - Mark J. Mulligan
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA;
- Department of Pediatrics, Emory University School of Medicine and Children’s Healthcare of Atlanta, Atlanta, GA, 30322, USA
- Division of Infectious Diseases and Immunology, Department of Medicine, and New York University (NYU) Langone Vaccine Center, NYU School of Medicine, New York, NY 10016, USA
- Correspondence: ; Tel.: +1-212-263-9410; Fax: +1-646-501-4645
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14
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Interferon Gamma Reprograms Host Mitochondrial Metabolism through Inhibition of Complex II To Control Intracellular Bacterial Replication. Infect Immun 2020; 88:IAI.00744-19. [PMID: 31740527 DOI: 10.1128/iai.00744-19] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 11/12/2019] [Indexed: 12/21/2022] Open
Abstract
The mechanisms by which interferon gamma (IFN-γ) controls the replication of cytosolic pathogens independent of responses, such as the generation of reactive oxygen species/reactive nitrogen species (ROS/RNS), have not been fully elucidated. In the current study, we developed a model using Francisella tularensis, the causative agent of tularemia, in which pathways triggered by IFN-γ commonly associated with bacterial control were not required. Using this model, we demonstrated that IFN-γ-mediated production of itaconate and its ability to impair host mitochondrial function, independent of activity on the pathogen, were central for the restriction of bacterial replication in vitro and in vivo We then demonstrate that IFN-γ-driven itaconate production was dispensable, as directly targeting complex II using cell membrane-permeable metabolites also controlled infection. Together, these findings show that while reprogramming of mitochondrial metabolism is a key factor in IFN-γ control of intracellular bacteria, the development of antimicrobial strategies based on targeting host mitochondrial metabolism independent of this cytokine may be an effective therapeutic approach.
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15
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Nouwen LV, Everts B. Pathogens MenTORing Macrophages and Dendritic Cells: Manipulation of mTOR and Cellular Metabolism to Promote Immune Escape. Cells 2020; 9:cells9010161. [PMID: 31936570 PMCID: PMC7017145 DOI: 10.3390/cells9010161] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/01/2020] [Accepted: 01/07/2020] [Indexed: 02/06/2023] Open
Abstract
Myeloid cells, including macrophages and dendritic cells, represent an important first line of defense against infections. Upon recognition of pathogens, these cells undergo a metabolic reprogramming that supports their activation and ability to respond to the invading pathogens. An important metabolic regulator of these cells is mammalian target of rapamycin (mTOR). During infection, pathogens use host metabolic pathways to scavenge host nutrients, as well as target metabolic pathways for subversion of the host immune response that together facilitate pathogen survival. Given the pivotal role of mTOR in controlling metabolism and DC and macrophage function, pathogens have evolved strategies to target this pathway to manipulate these cells. This review seeks to discuss the most recent insights into how pathogens target DC and macrophage metabolism to subvert potential deleterious immune responses against them, by focusing on the metabolic pathways that are known to regulate and to be regulated by mTOR signaling including amino acid, lipid and carbohydrate metabolism, and autophagy.
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16
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Liao ST, Han C, Xu DQ, Fu XW, Wang JS, Kong LY. 4-Octyl itaconate inhibits aerobic glycolysis by targeting GAPDH to exert anti-inflammatory effects. Nat Commun 2019; 10:5091. [PMID: 31704924 PMCID: PMC6841710 DOI: 10.1038/s41467-019-13078-5] [Citation(s) in RCA: 215] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Accepted: 10/18/2019] [Indexed: 12/14/2022] Open
Abstract
Activated macrophages switch from oxidative phosphorylation to aerobic glycolysis, similar to the Warburg effect, presenting a potential therapeutic target in inflammatory disease. The endogenous metabolite itaconate has been reported to regulate macrophage function, but its precise mechanism is not clear. Here, we show that 4-octyl itaconate (4-OI, a cell-permeable itaconate derivative) directly alkylates cysteine residue 22 on the glycolytic enzyme GAPDH and decreases its enzyme activity. Glycolytic flux analysis by U13C glucose tracing provides evidence that 4-OI blocks glycolytic flux at GAPDH. 4-OI thereby downregulates aerobic glycolysis in activated macrophages, which is required for its anti-inflammatory effects. The anti-inflammatory effects of 4-OI are replicated by heptelidic acid, 2-DG and reversed by increasing wild-type (but not C22A mutant) GAPDH expression. 4-OI protects against lipopolysaccharide-induced lethality in vivo and inhibits cytokine release. These findings show that 4-OI has anti-inflammatory effects by targeting GAPDH to decrease aerobic glycolysis in macrophages.
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Affiliation(s)
- Shan-Ting Liao
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 24 Tong Jia Xiang, 210009, Nanjing, China
| | - Chao Han
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 24 Tong Jia Xiang, 210009, Nanjing, China
| | - Ding-Qiao Xu
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 24 Tong Jia Xiang, 210009, Nanjing, China
| | - Xiao-Wei Fu
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 24 Tong Jia Xiang, 210009, Nanjing, China
| | - Jun-Song Wang
- Center for Molecular Metabolism, Nanjing University of Science and Technology, 200 Xiao Ling Wei, 210014, Nanjing, China.
| | - Ling-Yi Kong
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 24 Tong Jia Xiang, 210009, Nanjing, China.
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17
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Knight M, Stanley S. HIF-1α as a central mediator of cellular resistance to intracellular pathogens. Curr Opin Immunol 2019; 60:111-116. [PMID: 31229914 DOI: 10.1016/j.coi.2019.05.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 04/30/2019] [Accepted: 05/11/2019] [Indexed: 12/12/2022]
Abstract
Hypoxia-inducible transcription factor-1α (HIF-1α) was originally identified as a master regulator of cellular responses to hypoxia. More recently, HIF-1α has emerged as a critical regulator of immune cell function that couples shifts in cellular metabolism to cell type-specific transcriptional outputs. Activation of macrophages with inflammatory stimuli leads to induction of the metabolic program aerobic glycolysis and to HIF-1α stabilization, which reinforce one another in a positive feedback loop that helps drive macrophage activation. This activation of aerobic glycolysis and HIF-1α is important both for production of inflammatory cytokines, such as IL-1β, and for cell intrinsic control of infection. Here, we review the importance of HIF-1α for control of bacterial, fungal, and protozoan intracellular pathogens, highlighting recent findings that reveal mechanisms by which HIF-1α is activated during infection and how HIF-1α coordinates antimicrobial responses of macrophages.
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Affiliation(s)
- Matthew Knight
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, United States
| | - Sarah Stanley
- Department of Molecular and Cell Biology, Division of Immunology and Pathogenesis, University of California, Berkeley, CA, United States; School of Public Health, Division of Infectious Diseases and Vaccinology, University of California, Berkeley, CA, United States.
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18
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Koo SJ, Garg NJ. Metabolic programming of macrophage functions and pathogens control. Redox Biol 2019; 24:101198. [PMID: 31048245 PMCID: PMC6488820 DOI: 10.1016/j.redox.2019.101198] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Accepted: 04/09/2019] [Indexed: 12/15/2022] Open
Abstract
Macrophages (Mφ) are central players in mediating proinflammatory and immunomodulatory functions. Unchecked Mφ activities contribute to pathology across many diseases, including those caused by infectious pathogens and metabolic disorders. A fine balance of Mφ responses is crucial, which may be achieved by enforcing appropriate bioenergetics pathways. Metabolism serves as the provider of energy, substrates, and byproducts that support differential Mφ characteristics. The metabolic properties that control the polarization and response of Mφ remain to be fully uncovered for use in managing infectious diseases. Here, we review the various metabolic states in Mφ and how they influence the cell function.
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Affiliation(s)
- Sue-Jie Koo
- Department of Pathology, University of Texas Medical Branch (UTMB), Galveston, TX, USA
| | - Nisha J Garg
- Department of Microbiology & Immunology, UTMB, Galveston, TX, USA; Institute for Human Infections and Immunity, UTMB, Galveston, TX, USA.
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19
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Abstract
Mitochondria are essential and highly dynamic organelles whose morphology is determined by a steady-state balance between fusion and fission. Mitochondrial morphology and function are tightly connected. Because they are involved in many important cellular processes, including energy production, cell-autonomous immunity, and apoptosis, mitochondria present an attractive target for pathogens. Here, we explore the relationship between host cell mitochondria and intracellular bacteria, with a focus on mitochondrial morphology and function, as well as apoptosis. Modulation of apoptosis can allow bacteria to establish their replicative niche or support bacterial dissemination. Furthermore, bacteria can manipulate mitochondrial morphology and function through secreted effector proteins and can also contribute to the establishment of a successful infection, e.g., by favoring access to nutrients and/or evasion of the immune system.
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20
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Eisenreich W, Rudel T, Heesemann J, Goebel W. How Viral and Intracellular Bacterial Pathogens Reprogram the Metabolism of Host Cells to Allow Their Intracellular Replication. Front Cell Infect Microbiol 2019; 9:42. [PMID: 30886834 PMCID: PMC6409310 DOI: 10.3389/fcimb.2019.00042] [Citation(s) in RCA: 129] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 02/08/2019] [Indexed: 12/12/2022] Open
Abstract
Viruses and intracellular bacterial pathogens (IBPs) have in common the need of suitable host cells for efficient replication and proliferation during infection. In human infections, the cell types which both groups of pathogens are using as hosts are indeed quite similar and include phagocytic immune cells, especially monocytes/macrophages (MOs/MPs) and dendritic cells (DCs), as well as nonprofessional phagocytes, like epithelial cells, fibroblasts and endothelial cells. These terminally differentiated cells are normally in a metabolically quiescent state when they are encountered by these pathogens during infection. This metabolic state of the host cells does not meet the extensive need for nutrients required for efficient intracellular replication of viruses and especially IBPs which, in contrast to the viral pathogens, have to perform their own specific intracellular metabolism to survive and efficiently replicate in their host cell niches. For this goal, viruses and IBPs have to reprogram the host cell metabolism in a pathogen-specific manner to increase the supply of nutrients, energy, and metabolites which have to be provided to the pathogen to allow its replication. In viral infections, this appears to be often achieved by the interaction of specific viral factors with central metabolic regulators, including oncogenes and tumor suppressors, or by the introduction of virus-specific oncogenes. Less is so far known on the mechanisms leading to metabolic reprogramming of the host cell by IBPs. However, the still scant data suggest that similar mechanisms may also determine the reprogramming of the host cell metabolism in IBP infections. In this review, we summarize and compare the present knowledge on this important, yet still poorly understood aspect of pathogenesis of human viral and especially IBP infections.
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Affiliation(s)
- Wolfgang Eisenreich
- Chair of Biochemistry, Department of Chemistry, Technische Universität München, Garching, Germany
| | - Thomas Rudel
- Chair of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Jürgen Heesemann
- Max von Pettenkofer-Institute, Ludwig Maximilian University of Munich, Munich, Germany
| | - Werner Goebel
- Max von Pettenkofer-Institute, Ludwig Maximilian University of Munich, Munich, Germany
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21
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Temporal Manipulation of Mitochondrial Function by Virulent Francisella tularensis To Limit Inflammation and Control Cell Death. Infect Immun 2018; 86:IAI.00044-18. [PMID: 29760217 DOI: 10.1128/iai.00044-18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 05/09/2018] [Indexed: 12/15/2022] Open
Abstract
Francisella tularensis subsp. tularensis is a highly pathogenic intracellular bacterium that suppresses host inflammation by impairing the metabolic shift from oxidative phosphorylation to glycolysis. Decreased mitochondrial metabolism is central to initiating a metabolic shift to glycolysis and regulating inflammation, but F. tularensis subsp. tularensis manipulation of host mitochondrial function has not been explored. We demonstrate, using extracellular flux analysis, that F. tularensis subsp. tularensis infection initially improves host macrophage mitochondrial bioenergetics in a capsule-dependent manner. Enhancement of mitochondrial function by F. tularensis subsp. tularensis allowed for modest replication and inhibition of apoptosis early after infection. However, using live cell imaging, we found that F. tularensis subsp. tularensis facilitated the loss of mitochondrial function at later time points during infection in a capsule-independent fashion. This loss of function was paired with oncosis and rapid bacterial replication. Inhibition of oncosis reduced intracellular bacterial numbers, underscoring the requirement for this process during F. tularensis subsp. tularensis infection. These findings establish that temporal mitochondrial manipulation by F. tularensis subsp. tularensis is critical for maintenance of a noninflammatory environment and subsequently aids in optimal replication and dissemination of this pathogenic organism.
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22
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Ireland R, Schwarz B, Nardone G, Wehrly TD, Broeckling CD, Chiramel AI, Best SM, Bosio CM. Unique Francisella Phosphatidylethanolamine Acts as a Potent Anti-Inflammatory Lipid. J Innate Immun 2018; 10:291-305. [PMID: 29969788 DOI: 10.1159/000489504] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 04/19/2018] [Indexed: 12/21/2022] Open
Abstract
Virulent Francisella tularensis subsp. tularensis (Ftt) is a dynamic, intracellular, bacterial pathogen. Its ability to evade and rapidly suppress host inflammatory responses is considered a key element for its profound virulence. We previously established that Ftt lipids play a role in inhibiting inflammation, but we did not determine the lipid species mediating this process. Here, we show that a unique, abundant, phosphatidylethanolamine (PE), present in Francisella, contributes to driving the suppression of inflammatory responses in human and mouse cells. Acyl chain lengths of this PE, C24: 0 and C10: 0, were key to the suppressive capabilities of Francisella PE. Addition of synthetic PE 24: 0-10: 0 resulted in the accumulation of PE in host cells for up to 24 h of incubation, and recapitulated the inhibition of inflammatory responses observed with native Ftt PE. Importantly, this novel PE significantly inhibited inflammatory responses driven by a medically and globally important flavivirus, dengue fever virus. Thus, targeting these lipids and/or the pathways that they manipulate represents a new strategy to combat immunosuppression engendered by Ftt, but they also show promise as a novel therapeutic intervention for significant viral infections.
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Affiliation(s)
- Robin Ireland
- Immunity to Pulmonary Pathogens Section, Laboratory of Bacteriology, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, Montana, USA
| | - Benjamin Schwarz
- Immunity to Pulmonary Pathogens Section, Laboratory of Bacteriology, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, Montana, USA
| | - Glenn Nardone
- Research Technologies Branch, NIAID, NIH, Bethesda, Maryland, USA
| | - Tara D Wehrly
- Immunity to Pulmonary Pathogens Section, Laboratory of Bacteriology, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, Montana, USA
| | - Corey D Broeckling
- Proteomics and Metabolomics Facility, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Abhilash I Chiramel
- Innate Immunity and Pathogenesis Section, Laboratory of Virology, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, Montana, USA
| | - Sonja M Best
- Innate Immunity and Pathogenesis Section, Laboratory of Virology, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, Montana, USA
| | - Catharine M Bosio
- Immunity to Pulmonary Pathogens Section, Laboratory of Bacteriology, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, Montana, USA
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23
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Sampath V, McCaig WD, Thanassi DG. Amino acid deprivation and central carbon metabolism regulate the production of outer membrane vesicles and tubes by Francisella. Mol Microbiol 2018; 107:523-541. [PMID: 29240272 DOI: 10.1111/mmi.13897] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 12/07/2017] [Accepted: 12/11/2017] [Indexed: 12/23/2022]
Abstract
Francisella tularensis is a highly virulent Gram-negative bacterial pathogen that causes the zoonotic disease tularemia. F. novicida, a model tularemia strain, produces spherical outer membrane vesicles (OMV), as well as novel tubular vesicles and extensions of the cell surface. These OMV and tubes (OMV/T) are produced in a regulated manner and contain known virulence factors. Mechanisms by which bacterial vesicles are produced and regulated are not well understood. We performed a genetic screen in F. novicida to decipher the molecular basis for regulated OMV/T formation, and identified both hypo- and hyper-vesiculating mutants. Mutations in fumA and tktA, involved in central carbon metabolism, and in FTN_0908 and FTN_1037, of unknown function, resulted in severe defects in OMV/T production. Cysteine deprivation was identified as the signal that triggers OMV/T formation in F. novicida during growth in rich medium. We also found that fully virulent F. tularensis produces OMV/T in a similarly regulated manner. Further analysis revealed that OMV/T production is responsive to deprivation of essential amino acids in addition to cysteine, and that the hypo-vesiculating mutants are defective in responding to this signal. Thus, amino acid starvation, such as encountered by Francisella during host cell invasion, regulates the production of membrane-derived structures.
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Affiliation(s)
- Vinaya Sampath
- Department of Molecular Genetics and Microbiology, Center for Infectious Diseases, Stony Brook University, Stony Brook, NY 11794, USA
| | - William D McCaig
- Department of Molecular Genetics and Microbiology, Center for Infectious Diseases, Stony Brook University, Stony Brook, NY 11794, USA
| | - David G Thanassi
- Department of Molecular Genetics and Microbiology, Center for Infectious Diseases, Stony Brook University, Stony Brook, NY 11794, USA
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24
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Mahon RN, Hafner R. Applying Precision Medicine and Immunotherapy Advances from Oncology to Host-Directed Therapies for Infectious Diseases. Front Immunol 2017; 8:688. [PMID: 28706516 PMCID: PMC5489679 DOI: 10.3389/fimmu.2017.00688] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 05/29/2017] [Indexed: 12/11/2022] Open
Abstract
To meet the challenges of increasing antimicrobial resistance, the infectious disease community needs innovative therapeutics. Precision medicine and immunotherapies are transforming cancer therapeutics by targeting the regulatory signaling pathways that are involved not only in malignancies but also in the metabolic and immunologic function of the tumor microenvironment. Infectious diseases target many of the same regulatory pathways as they modulate host metabolic functions for their own nutritional requirements and to impede host immunity. These similarities and the advances made in precision medicine and immuno-oncology that are relevant for the current development of host-directed therapies (HDTs) to treat infectious diseases are discussed. To harness this potential, improvements in drug screening methods and development of assays that utilize the research tools including high throughput multiplexes already developed by oncology are essential. A multidisciplinary approach that brings together immunologists, infectious disease specialists, and oncologists will be necessary to fully develop the potential of HDTs.
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Affiliation(s)
- Robert N Mahon
- Division of AIDS, Columbus Technologies, Inc., Contractor to National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Richard Hafner
- Division of AIDS, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
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25
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Holland KM, Rosa SJ, Kristjansdottir K, Wolfgeher D, Franz BJ, Zarrella TM, Kumar S, Sunagar R, Singh A, Bakshi CS, Namjoshi P, Barry EM, Sellati TJ, Kron SJ, Gosselin EJ, Reed DS, Hazlett KRO. Differential Growth of Francisella tularensis, Which Alters Expression of Virulence Factors, Dominant Antigens, and Surface-Carbohydrate Synthases, Governs the Apparent Virulence of Ft SchuS4 to Immunized Animals. Front Microbiol 2017; 8:1158. [PMID: 28690600 PMCID: PMC5479911 DOI: 10.3389/fmicb.2017.01158] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 06/07/2017] [Indexed: 12/29/2022] Open
Abstract
The gram-negative bacterium Francisella tularensis (Ft) is both a potential biological weapon and a naturally occurring microbe that survives in arthropods, fresh water amoeba, and mammals with distinct phenotypes in various environments. Previously, we used a number of measurements to characterize Ft grown in Brain-Heart Infusion (BHI) broth as (1) more similar to infection-derived bacteria, and (2) slightly more virulent in naïve animals, compared to Ft grown in Mueller Hinton Broth (MHB). In these studies we observed that the free amino acids in MHB repress expression of select Ft virulence factors by an unknown mechanism. Here, we tested the hypotheses that Ft grown in BHI (BHI-Ft) accurately displays a full protein composition more similar to that reported for infection-derived Ft and that this similarity would make BHI-Ft more susceptible to pre-existing, vaccine-induced immunity than MHB-Ft. We performed comprehensive proteomic analysis of Ft grown in MHB, BHI, and BHI supplemented with casamino acids (BCA) and compared our findings to published “omics” data derived from Ft grown in vivo. Based on the abundance of ~1,000 proteins, the fingerprint of BHI-Ft is one of nutrient-deprived bacteria that—through induction of a stringent-starvation-like response—have induced the FevR regulon for expression of the bacterium's virulence factors, immuno-dominant antigens, and surface-carbohydrate synthases. To test the notion that increased abundance of dominant antigens expressed by BHI-Ft would render these bacteria more susceptible to pre-existing, vaccine-induced immunity, we employed a battery of LVS-vaccination and S4-challenge protocols using MHB- and BHI-grown Ft S4. Contrary to our hypothesis, these experiments reveal that LVS-immunization provides a barrier to infection that is significantly more effective against an MHB-S4 challenge than a BHI-S4 challenge. The differences in apparent virulence to immunized mice are profoundly greater than those observed with primary infection of naïve mice. Our findings suggest that tularemia vaccination studies should be critically evaluated in regard to the growth conditions of the challenge agent.
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Affiliation(s)
- Kristen M Holland
- Department of Immunology and Microbial Disease, Albany Medical CollegeAlbany, NY, United States
| | - Sarah J Rosa
- Department of Immunology and Microbial Disease, Albany Medical CollegeAlbany, NY, United States
| | | | - Donald Wolfgeher
- Department of Molecular Genetics and Cell Biology, University of ChicagoChicago, IL, United States
| | - Brian J Franz
- Department of Immunology and Microbial Disease, Albany Medical CollegeAlbany, NY, United States
| | - Tiffany M Zarrella
- Department of Immunology and Microbial Disease, Albany Medical CollegeAlbany, NY, United States
| | - Sudeep Kumar
- Department of Immunology and Microbial Disease, Albany Medical CollegeAlbany, NY, United States
| | - Raju Sunagar
- Department of Immunology and Microbial Disease, Albany Medical CollegeAlbany, NY, United States
| | - Anju Singh
- Trudeau InstituteSaranac Lake, NY, United States
| | - Chandra S Bakshi
- Department of Microbiology and Immunology, New York Medical CollegeValhalla, NY, United States
| | - Prachi Namjoshi
- Department of Immunology and Microbial Disease, Albany Medical CollegeAlbany, NY, United States
| | - Eileen M Barry
- School of Medicine, University of MarylandBaltimore, MD, United States
| | | | - Stephen J Kron
- Department of Molecular Genetics and Cell Biology, University of ChicagoChicago, IL, United States
| | - Edmund J Gosselin
- Department of Immunology and Microbial Disease, Albany Medical CollegeAlbany, NY, United States
| | - Douglas S Reed
- Center for Vaccine Research, University of PittsburghPittsburgh, PA, United States
| | - Karsten R O Hazlett
- Department of Immunology and Microbial Disease, Albany Medical CollegeAlbany, NY, United States
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26
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Holland KM, Rosa SJ, Hazlett KRO. Francisella tularensis - Immune Cell Activator, Suppressor, or Stealthy Evader: The Evolving View from the Petri Dish. ACTA ACUST UNITED AC 2016; 7. [PMID: 27695643 PMCID: PMC5042348 DOI: 10.4172/2157-2526.1000144] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
One of the hallmarks of pulmonary tularemia, which results from inhalation of Francisella tularensis - a significant bioterrorism concern, is the lack of an acute TH1-biased inflammatory response in the early phase of disease (days 1–3) despite significant bacterial loads. In an effort to understand this apparent hypo-responsiveness, many laboratories have utilized in vitro cell-based models as tools to probe the nature and consequences of host cell interactions with F. tularensis. The first uses of this model suggested that mammalian host cells recognize this bacterium principally through TLR2 to evoke a robust, classical TH1-biased cytokine response including TNF, IL-6, IL-1β, and IFN-γ. Others used this model in concert with a variety of non-genetic perturbations of the bacterial-host cell interaction and suggested that F. tularensis actively-suppressed the cellular response. Consistent with this notion, others engaged this model to assess isogenic mutants and, in many cases, found the mutant bacteria to be more pro-inflammatory than their WT counter-parts. Frequently, these observations were interpreted as evidence for the immunosuppressive function of the gene of interest. However, recently appreciated roles of the health of the bacterium and the impact of host factors have refined this model to suggest a “stealthy” mode of bacterial-host cell interaction (rather than one involving active suppression) consistent with the observations during early phase disease.
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Affiliation(s)
- Kristen M Holland
- Center for Immunology & Microbial Disease, Albany Medical College, Albany, NY 12208, USA
| | - Sarah J Rosa
- Center for Immunology & Microbial Disease, Albany Medical College, Albany, NY 12208, USA
| | - Karsten R O Hazlett
- Center for Immunology & Microbial Disease, Albany Medical College, Albany, NY 12208, USA
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