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Bhushan G, Castano V, Wong Fok Lung T, Chandler C, McConville TH, Ernst RK, Prince AS, Ahn D. Lipid A modification of colistin-resistant Klebsiella pneumoniae does not alter innate immune response in a mouse model of pneumonia. Infect Immun 2024; 92:e0001624. [PMID: 38771050 DOI: 10.1128/iai.00016-24] [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: 01/26/2024] [Accepted: 04/26/2024] [Indexed: 05/22/2024] Open
Abstract
Polymyxin resistance in carbapenem-resistant Klebsiella pneumoniae bacteria is associated with high morbidity and mortality in vulnerable populations throughout the world. Ineffective antimicrobial activity by these last resort therapeutics can occur by transfer of mcr-1, a plasmid-mediated resistance gene, causing modification of the lipid A portion of lipopolysaccharide (LPS) and disruption of the interactions between polymyxins and lipid A. Whether this modification alters the innate host immune response or carries a high fitness cost in the bacteria is not well established. To investigate this, we studied infection with K. pneumoniae (KP) ATCC 13883 harboring either the mcr-1 plasmid (pmcr-1) or the vector control (pBCSK) ATCC 13883. Bacterial fitness characteristics of mcr-1 acquisition were evaluated. Differentiated human monocytes (THP-1s) were stimulated with KP bacterial strains or purified LPS from both parent isolates and isolates harboring mcr-1. Cell culture supernatants were analyzed for cytokine production. A bacterial pneumonia model in WT C57/BL6J mice was used to monitor immune cell recruitment, cytokine induction, and bacterial clearance in the bronchoalveolar lavage fluid (BALF). Isolates harboring mcr-1 had increased colistin MIC compared to the parent isolates but did not alter bacterial fitness. Few differences in cytokines were observed with purified LPS from mcr-1 expressing bacteria in vitro. However, in a mouse pneumonia model, no bacterial clearance defect was observed between pmcr-1-harboring KP and parent isolates. Consistently, no differences in cytokine production or immune cell recruitment in the BALF were observed, suggesting that other mechanisms outweigh the effect of these lipid A mutations in LPS.
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Affiliation(s)
- Gitanjali Bhushan
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York, USA
| | - Victor Castano
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York, USA
| | - Tania Wong Fok Lung
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York, USA
| | - Courtney Chandler
- Department of Microbial Pathogenesis, University of Maryland, School of Dentistry, Baltimore, Maryland, USA
| | - Thomas H McConville
- Department of Medicine, Columbia University Irving Medical Center, New York, New York, USA
| | - Robert K Ernst
- Department of Microbial Pathogenesis, University of Maryland, School of Dentistry, Baltimore, Maryland, USA
| | - Alice S Prince
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York, USA
| | - Danielle Ahn
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York, USA
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2
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Jastrab JB, Kagan JC. Strategies of bacterial detection by inflammasomes. Cell Chem Biol 2024; 31:835-850. [PMID: 38636521 PMCID: PMC11103797 DOI: 10.1016/j.chembiol.2024.03.009] [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: 12/22/2023] [Revised: 03/09/2024] [Accepted: 03/26/2024] [Indexed: 04/20/2024]
Abstract
Mammalian innate immunity is regulated by pattern-recognition receptors (PRRs) and guard proteins, which use distinct strategies to detect infections. PRRs detect bacterial molecules directly, whereas guards detect host cell manipulations by microbial virulence factors. Despite sensing infection through different mechanisms, both classes of innate immune sensors can activate the inflammasome, an immune complex that can mediate cell death and inflammation. Inflammasome-mediated immune responses are crucial for host defense against many bacterial pathogens and prevent invasion by non-pathogenic organisms. In this review, we discuss the mechanisms by which inflammasomes are stimulated by PRRs and guards during bacterial infection, and the strategies used by virulent bacteria to evade inflammasome-mediated immunity.
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Affiliation(s)
- Jordan B Jastrab
- Division of Gastroenterology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA; Division of Infectious Diseases, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Jonathan C Kagan
- Division of Gastroenterology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA.
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Li J, Liu C, Xu Y, Ling C, Tang Z, Kiram A, Hu Z, Zhu Z, Qiu Y, Liu Z. Gut Microbiota Alterations in Adolescent Idiopathic Scoliosis Are Associated with Aberrant Bone Homeostasis. Orthop Surg 2024; 16:965-975. [PMID: 38389213 PMCID: PMC10984819 DOI: 10.1111/os.14019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 11/24/2023] [Accepted: 01/26/2024] [Indexed: 02/24/2024] Open
Abstract
OBJECTIVE Low bone mineral density is the major prognostic factor for adolescent idiopathic scoliosis (AIS), but the underlying mechanisms remain unclear. Accumulating evidence suggests that gut microbiota (GM) have the potential to affect bone development, and the GM signatures are altered in AIS patients. However, the effect of GM alterations on aberrant bone homeostasis in AIS remains unclear. This study aims to investigate the GM profile in AIS patients with different bone mineral density (BMD) and explore the association between GM, osteopenia, and aberrant bone turnover. METHODS A total of 126 patients with AIS who received surgical treatment were retrospectively included in this study. We analyzed the composition of the GM by 16S rRNA sequencing and BMD by dual X-ray absorptiometry. Based on the BMD of the femur neck, the patients were divided into the osteopenia group (OPN) if the Z score < -1, and the normal (NOR) group if the Z score ≥ -1 SD compared to the healthy control. For the 16S rRNA sequencing, the raw reads were filtered to remove low-quality reads, and operational taxonomic units were identified with the Uparse program. Weighted UniFrac distance matrix for the beta-diversity metrics and principal coordinate analysis (PCoA) was performed, and the statistical comparisons were made with permutational multivariate analysis of variance (PERMANOVA) and analysis of similarity (ANONISM). Linear discriminant analysis effect size (LEfSe) was used to identify the enriched species in two groups. The "Random forest" was applied to determine the optimal biomarker for OPN according to the mean decrease in Gini value. The metabolic function was predicted by the Tax4Fun analysis. The Pearson correlation coefficient was used to evaluate the associations between GM species, bone turnover markers, and BMD. RESULTS The serum β-CTX was increased in the OPN group (n = 67) compared to the NOR group (n = 59). Patients in OPN groups showed significantly decreased α diversity indicated by the Shannon index. Principal coordinate analysis (PCoA) analysis showed significant clustering of GM between OPN and NOR groups. At genus level, the Escherichia-Shigella and Faecalibacterium were significantly enriched in the OPN group compared to that in the NOR group (p < 0.05), whereas the abundance of Prevotella was significantly decreased (p = 0.0012). The relative abundance of Megamonas and Prevotella was positively correlated with the femur BMD. The abundance of Escherichia-Shigella was negatively correlated with femur BMD and positively correlated with serum β-CTX levels. Functional analysis revealed significant differences in starch and sucrose metabolism, pyruvate and cysteine, and methionine metabolism between NOR and OPN groups. CONCLUSION The alterations of GM in AIS patients are correlated with osteopenia. The association between enriched species, BMD, and bone turnover markers provides novel diagnostic and therapeutic targets for the clinical management of AIS.
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Affiliation(s)
- Jie Li
- Division of Spine Surgery, Department of Orthopedic SurgeryNanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical SchoolNanjingChina
| | - Changwei Liu
- Division of Spine Surgery, Department of Orthopedic SurgeryNanjing Drum Tower Hospital, Clinical College of Nanjing Medical UniversityNanjingChina
| | - Yanjie Xu
- Division of Spine Surgery, Department of Orthopedic SurgeryNanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical SchoolNanjingChina
| | - Chen Ling
- Division of Spine Surgery, Department of Orthopedic SurgeryNanjing Drum Tower Hospital, Clinical College of Nanjing Medical UniversityNanjingChina
| | - Ziyang Tang
- Division of Spine Surgery, Department of Orthopedic SurgeryNanjing Drum Tower Hospital, Clinical College of Nanjing Medical UniversityNanjingChina
| | - Abdukahar Kiram
- Division of Spine Surgery, Department of Orthopedic SurgeryNanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical SchoolNanjingChina
| | - Zongshan Hu
- Division of Spine Surgery, Department of Orthopedic SurgeryNanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical SchoolNanjingChina
| | - Zezhang Zhu
- Division of Spine Surgery, Department of Orthopedic SurgeryNanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical SchoolNanjingChina
- Division of Spine Surgery, Department of Orthopedic SurgeryNanjing Drum Tower Hospital, Clinical College of Nanjing Medical UniversityNanjingChina
| | - Yong Qiu
- Division of Spine Surgery, Department of Orthopedic SurgeryNanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical SchoolNanjingChina
- Division of Spine Surgery, Department of Orthopedic SurgeryNanjing Drum Tower Hospital, Clinical College of Nanjing Medical UniversityNanjingChina
| | - Zhen Liu
- Division of Spine Surgery, Department of Orthopedic SurgeryNanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical SchoolNanjingChina
- Division of Spine Surgery, Department of Orthopedic SurgeryNanjing Drum Tower Hospital, Clinical College of Nanjing Medical UniversityNanjingChina
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Ascari A, Frölich S, Zang M, Tran ENH, Wilson DW, Morona R, Eijkelkamp BA. Shigella flexneri remodeling and consumption of host lipids during infection. J Bacteriol 2023; 205:e0032023. [PMID: 37991380 PMCID: PMC10729657 DOI: 10.1128/jb.00320-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 11/10/2023] [Indexed: 11/23/2023] Open
Abstract
IMPORTANCE Bacterial pathogens have vastly distinct sites that they inhabit during infection. This requires adaptation due to changes in nutrient availability and antimicrobial stress. The bacterial surface is a primary barrier, and here, we show that the bacterial pathogen Shigella flexneri increases its surface decorations when it transitions to an intracellular lifestyle. We also observed changes in bacterial and host cell fatty acid homeostasis. Specifically, intracellular S. flexneri increased the expression of their fatty acid degradation pathway, while the host cell lipid pool was significantly depleted. Importantly, bacterial proliferation could be inhibited by fatty acid supplementation of host cells, thereby providing novel insights into the possible link between human malnutrition and susceptibility to S. flexneri.
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Affiliation(s)
- Alice Ascari
- Department of Molecular and Biomedical Science, School of Biological Sciences, Research Centre for Infectious Diseases, University of Adelaide, Adelaide, Australia
- Molecular Sciences and Technology, College of Science and Engineering, Flinders University, Adelaide, Australia
| | - Sonja Frölich
- Department of Molecular and Biomedical Science, School of Biological Sciences, Research Centre for Infectious Diseases, University of Adelaide, Adelaide, Australia
- Institute for Photonics and Advanced Sensing (IPAS), University of Adelaide, Adelaide, Australia
| | - Maoge Zang
- Molecular Sciences and Technology, College of Science and Engineering, Flinders University, Adelaide, Australia
| | - Elizabeth N. H. Tran
- Department of Molecular and Biomedical Science, School of Biological Sciences, Research Centre for Infectious Diseases, University of Adelaide, Adelaide, Australia
| | - Danny W. Wilson
- Department of Molecular and Biomedical Science, School of Biological Sciences, Research Centre for Infectious Diseases, University of Adelaide, Adelaide, Australia
- Institute for Photonics and Advanced Sensing (IPAS), University of Adelaide, Adelaide, Australia
| | - Renato Morona
- Department of Molecular and Biomedical Science, School of Biological Sciences, Research Centre for Infectious Diseases, University of Adelaide, Adelaide, Australia
| | - Bart A. Eijkelkamp
- Molecular Sciences and Technology, College of Science and Engineering, Flinders University, Adelaide, Australia
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Matanza XM, Clements A. Pathogenicity and virulence of Shigella sonnei: A highly drug-resistant pathogen of increasing prevalence. Virulence 2023; 14:2280838. [PMID: 37994877 PMCID: PMC10732612 DOI: 10.1080/21505594.2023.2280838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 11/01/2023] [Indexed: 11/24/2023] Open
Abstract
Shigella spp. are the causative agent of shigellosis (or bacillary dysentery), a diarrhoeal disease characterized for the bacterial invasion of gut epithelial cells. Among the 4 species included in the genus, Shigella flexneri is principally responsible for the disease in the developing world while Shigella sonnei is the main causative agent in high-income countries. Remarkably, as more countries improve their socioeconomic conditions, we observe an increase in the relative prevalence of S. sonnei. To date, the reasons behind this change in aetiology depending on economic growth are not understood. S. flexneri has been widely used as a model to study the pathogenesis of the genus, but as more research data are collected, important discrepancies with S. sonnei have come to light. In comparison to S. flexneri, S. sonnei can be differentiated in numerous aspects; it presents a characteristic O-antigen identical to that of one serogroup of the environmental bacterium Plesiomonas shigelloides, a group 4 capsule, antibacterial mechanisms to outcompete and displace gut commensal bacteria, and a poorer adaptation to an intracellular lifestyle. In addition, the World Health Organization (WHO) have recognized the significant threat posed by antibiotic-resistant strains of S. sonnei, demanding new approaches. This review gathers knowledge on what is known about S. sonnei within the context of other Shigella spp. and aims to open the door for future research on understanding the increasing spread of this pathogen.
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Affiliation(s)
- Xosé M. Matanza
- Centre for Bacterial Resistance Biology, Department of Life Sciences, Imperial College London, London, UK
| | - Abigail Clements
- Centre for Bacterial Resistance Biology, Department of Life Sciences, Imperial College London, London, UK
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Varma VP, Bankala R, Kumar A, Gawai S, Faisal SM. Differential modulation of innate immune response by lipopolysaccharide of Leptospira. Open Biol 2023; 13:230101. [PMID: 37935355 PMCID: PMC10645091 DOI: 10.1098/rsob.230101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 08/16/2023] [Indexed: 11/09/2023] Open
Abstract
Leptospirosis is a worldwide zoonosis caused by pathogenic Leptospira spp. having more than 300 serovars. These serovars can infect a variety of hosts, some being asymptomatic carriers and others showing varied symptoms of mild to severe infection. Since lipopolysaccharide (LPS) is the major antigen which defines serovar specificity, this different course of infection may be attributed to a differential innate response against this antigen. Previous studies have shown that Leptospira LPS is less endotoxic. However, it is unclear whether there is a difference in the ability of LPS isolated from different serovars to modulate the innate response. In this study, we purified LPS from three widely prevalent pathogenic serovars, i.e. Icterohaemorrhagiae strain RGA, Pomona, Hardjo, and from non-pathogenic L. biflexa serovar semeranga strain Potac 1 collectively termed as L-LPS and tested their ability to modulate innate response in macrophages from both resistant (mice) and susceptible (human and bovine) hosts. L-LPS induced differential response being more proinflammatory in mouse and less proinflammatory in human and bovine macrophages but overall less immunostimulatory than E. coli LPS (E-LPS). Irrespective of serovar, this response was TLR2-dependent in humans, whereas TLR4-dependent/CD14-independent in mouse using MyD88 adapter and signalling through P38 and ERK-dependent MAP kinase pathway. L-LPS-activated macrophages were able to phagocytose Leptospira and this effect was significantly higher or more pronounced when the macrophages were stimulated with L-LPS from the corresponding serovar. L-LPS activated both canonical and non-canonical inflammasome, producing IL-1β without inducing pyroptosis. Further, L-LPS induced both TNF-mediated early and NO-mediated late apoptosis. Altogether, these results indicate that L-LPS induces a differential innate response that is quite distinct from that induced by E-LPS and may be attributed to the structural differences and its atypical nature.
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Affiliation(s)
- Vivek P. Varma
- Laboratory of Vaccine Immunology, National Institute of Animal Biotechnology, Hyderabad 500032, India
- Graduate Studies, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - Ramudu Bankala
- Laboratory of Vaccine Immunology, National Institute of Animal Biotechnology, Hyderabad 500032, India
| | - Ajay Kumar
- Laboratory of Vaccine Immunology, National Institute of Animal Biotechnology, Hyderabad 500032, India
- Regional Centre for Biotechnology, Faridabad, India
| | - Shashikant Gawai
- Laboratory of Vaccine Immunology, National Institute of Animal Biotechnology, Hyderabad 500032, India
| | - Syed M. Faisal
- Laboratory of Vaccine Immunology, National Institute of Animal Biotechnology, Hyderabad 500032, India
- Regional Centre for Biotechnology, Faridabad, India
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7
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Wang KC, Lerche MH, Ardenkjær-Larsen JH, Jensen PR. Formate Metabolism in Shigella flexneri and Its Effect on HeLa Cells at Different Stages during the Infectious Process. Microbiol Spectr 2023; 11:e0063122. [PMID: 37042762 PMCID: PMC10269805 DOI: 10.1128/spectrum.00631-22] [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: 03/25/2022] [Accepted: 03/16/2023] [Indexed: 04/13/2023] Open
Abstract
Shigellosis caused by Shigella is one of the most important foodborne illnesses in global health, but little is known about the metabolic cross talk between this bacterial pathogen and its host cells during the different stages of the infection process. A detailed understanding of the metabolism can potentially lead to new drug targets remedying the pressing problem of antibiotic resistance. Here, we use stable isotope-resolved metabolomics as an unbiased and fast method to investigate how Shigella metabolizes 13C-glucose in three different environments: inside the host cells, adhering to the host cells, and alone in suspension. We find that especially formate metabolism by bacteria is sensitive to these different environments. The role of formate in pathogen metabolism is sparsely described in the literature compared to the roles of acetate and butyrate. However, its metabolic pathway is regarded as a potential drug target due to its production in microorganisms and its absence in humans. Our study provides new knowledge about the regulatory effect of formate. Bacterial metabolism of formate is pH dependent when studied alone in culture medium, whereas this effect is less pronounced when the bacteria adhere to the host cells. Once the bacteria are inside the host cells, we find that formate accumulation is reduced. Formate also affects the host cells resulting in a reduced infection rate. This was correlated to an increased immune response. Thus, intriguingly formate plays a double role in pathogenesis by increasing the virulence of Shigella and at the same time stimulating the immune response of the host. IMPORTANCE Bacterial infection is a pressing societal concern due to development of resistance toward known antibiotics. Central carbon metabolism has been suggested as a potential new target for drug development, but metabolic changes upon infection remain incompletely understood. Here, we used a cellular infection model to study how the bacterial pathogen Shigella adapts its metabolism depending on the environment starting from the extracellular medium until Shigella successfully invaded and proliferated inside host cells. The mixed-acid fermentation of Shigella was the major metabolic pathway during the infectious process, and the glucose-derived metabolite formate surprisingly played a divergent role in the pathogen and in the host cell. Our data show reduced infection rate when both host cells and bacteria were treated with formate, which correlated with an upregulated immune response in the host cells. The formate metabolism in Shigella thus potentially provides a route toward alternative treatment strategies for Shigella prevention.
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Affiliation(s)
- Ke-Chuan Wang
- Center for Hyperpolarization in Magnetic Resonance, Department of Health Technology, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Mathilde Hauge Lerche
- Center for Hyperpolarization in Magnetic Resonance, Department of Health Technology, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Jan Henrik Ardenkjær-Larsen
- Center for Hyperpolarization in Magnetic Resonance, Department of Health Technology, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Pernille Rose Jensen
- Center for Hyperpolarization in Magnetic Resonance, Department of Health Technology, Technical University of Denmark, Kongens Lyngby, Denmark
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The Impact of Colistin Resistance on the Activation of Innate Immunity by Lipopolysaccharide Modification. Infect Immun 2023; 91:e0001223. [PMID: 36722977 PMCID: PMC9933656 DOI: 10.1128/iai.00012-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Colistin resistance is acquired by different lipopolysaccharide (LPS) modifications. We proposed to evaluate the of effect in vivo colistin resistance acquisition on the innate immune response. We used a pair of ST11 clone Klebsiella pneumoniae strains: an OXA-48, CTX-M-15 K. pneumoniae strain susceptible to colistin (CS-Kp) isolated from a urinary infection and its colistin-resistant variant (CR-Kp) from the same patient after prolonged treatment with colistin. No mutation of previously described genes for colistin resistance (pmrA, pmrB, mgrB, phoP/Q, arnA, arnC, arnT, ugdH, and crrAB) was found in the CR-Kp genome; however, LPS modifications were characterized by negative-ion matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. The strains were cocultured with human monocytes to determine their survival after phagocytosis and induction to apoptosis. Also, monocytes were stimulated with bacterial LPS to study cytokine and immune checkpoint production. The addition of 4-amino-4-deoxy-l-arabinose (Ara4N) to lipid A of CR-Kp accounted for the colistin resistance. CR-Kp survived significantly longer inside human monocytes after being phagocytosed than did the CS-Kp strain. In addition, LPS from CR-Kp induced both higher apoptosis in monocytes and higher levels of cytokine and immune checkpoint production than LPS from CS-Kp. Our data reveal a variable impact of colistin resistance on the innate immune system, depending on the responsible mechanism. Adding Ara4N to LPS in K. pneumoniae increases bacterial survival after phagocytosis and elicits a higher inflammatory response than its colistin-susceptible counterpart.
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Maekawa T, Kashkar H, Coll NS. Dying in self-defence: a comparative overview of immunogenic cell death signalling in animals and plants. Cell Death Differ 2023; 30:258-268. [PMID: 36195671 PMCID: PMC9950082 DOI: 10.1038/s41418-022-01060-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 08/29/2022] [Accepted: 09/06/2022] [Indexed: 11/05/2022] Open
Abstract
Host organisms utilise a range of genetically encoded cell death programmes in response to pathogen challenge. Host cell death can restrict pathogen proliferation by depleting their replicative niche and at the same time dying cells can alert neighbouring cells to prepare environmental conditions favouring future pathogen attacks. As expected, many pathogenic microbes have strategies to subvert host cell death to promote their virulence. The structural and lifestyle differences between animals and plants have been anticipated to shape very different host defence mechanisms. However, an emerging body of evidence indicates that several components of the host-pathogen interaction machinery are shared between the two major branches of eukaryotic life. Many proteins involved in cell death execution or cell death-associated immunity in plants and animals exert direct effects on endomembrane and loss of membrane integrity has been proposed to explain the potential immunogenicity of dying cells. In this review we aim to provide a comparative view on how cell death processes are linked to anti-microbial defence mechanisms in plants and animals and how pathogens interfere with these cell death programmes. In comparison to the several well-defined cell death programmes in animals, immunogenic cell death in plant defence is broadly defined as the hypersensitive response. Our comparative overview may help discerning whether specific types of immunogenic cell death exist in plants, and correspondingly, it may provide new hints for previously undiscovered cell death mechanism in animals.
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Affiliation(s)
- Takaki Maekawa
- Department of Biology, Institute for Plant Sciences, University of Cologne, 50674, Cologne, Germany.
- CEPLAS Cluster of Excellence on Plant Sciences at the University of Cologne, Cologne, Germany.
| | - Hamid Kashkar
- Faculty of Medicine and University Hospital of Cologne, Institute for Molecular Immunology, University of Cologne, 50931, Cologne, Germany.
- Faculty of Medicine and University Hospital of Cologne, Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931, Cologne, Germany.
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931, Cologne, Germany.
| | - Núria S Coll
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, 08193, Bellaterra, Spain.
- Consejo Superior de Investigaciones Científicas (CSIC), 08001, Barcelona, Spain.
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10
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Chen D, Guo Y, Yang Y. Liujunanwei decoction attenuates cisplatin-induced nausea and vomiting in a Rat-Pica model partially mediated by modulating the gut micsrobiome. Front Cell Infect Microbiol 2022; 12:876781. [PMID: 36061858 PMCID: PMC9437319 DOI: 10.3389/fcimb.2022.876781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 08/01/2022] [Indexed: 11/13/2022] Open
Abstract
Studies show that traditional Chinese medicine (TCM), such as Liujunanwei (LJAW) decoction, can play important roles in alleviating side effects of chemotherapy. The purpose of this study was to understand how LJAW can counter chemotherapy-induced emesis via alteration of gut microbiota. We evaluated the effect of LJAW on cisplatin (DDP)-induced nausea and vomiting using a rat-pica model. Rats react to emetic-producing stimuli with increased kaolin consumption, a phenomenon called pica. The rats were injected with cisplatin and then randomly assigned to the control (DDP), Ondansetron or LJAW. The intake of kaolin and chow diet as well as body weights were recorded every 24 hours. Fecal samples were collected prior to, after three and seven days of treatment. The expression of proteins was measured by western blot. The concentration of cytokines and serotonin was evaluated using ELISA assay kits. Kaolin consumption in rats induced by cisplatin was reduced by 16.5%, 22.5%, and 30.1% in the LJAW group compared to the DDP group at 24 hours, 48 hours and 72 hours, respectively (p>0.05). LJAW significantly increased the food intake of the rats (13.94 ± 4.73 g) during the first 24 hours as opposed to the DDP (9.23 ± 3.77 g) (p<0.05). 16S rRNA gene sequencing showed the abundance of Bacteroidetes increased in cisplatin treated rats. In addition, cisplatin injection caused an enrichment of Escherichia-Shigella and Enterococcus at the genus level. While, enrichment of Blautia and Lactobacillus was presented in LJAW treated rats. Serotonin decreased in LJAW treated intestine and medulla oblongata tissues. Further, the protein expression of tryptophan hydroxylase 1 (TPH1) a rate limiting enzyme of serotonin was inhibited in LJAW treated rat’s jejunum compared with cisplatin only treated rats. In addition, LJAW downregulated chemotherapy induced elevated inflammation. The results of this study indicated that LJAW is capable of decreasing cisplatin-induced kaolin intake in rat-nausea model (pica), which might be mediated through gut microbiome-induced anti-inflammation and anti-serotonin synthesis functions.
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Affiliation(s)
- Dongmei Chen
- Department of Integrative Oncology, China-Japan Friendship Hospital, Beijing, China
| | - Yi Guo
- Department of Gastroenterology, Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, China
| | - Yufei Yang
- Department of Oncology, Xi-Yuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- *Correspondence: Yufei Yang,
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Pizzato J, Tang W, Bernabeu S, Bonnin RA, Bille E, Farfour E, Guillard T, Barraud O, Cattoir V, Plouzeau C, Corvec S, Shahrezaei V, Dortet L, Larrouy-Maumus G. Discrimination of Escherichia coli, Shigella flexneri, and Shigella sonnei using lipid profiling by MALDI-TOF mass spectrometry paired with machine learning. Microbiologyopen 2022; 11:e1313. [PMID: 36004556 PMCID: PMC9405496 DOI: 10.1002/mbo3.1313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 08/03/2022] [Indexed: 11/15/2022] Open
Abstract
Matrix‐assisted laser desorption/ionization‐time of flight mass spectrometry (MALDI‐TOF MS) has become a staple in clinical microbiology laboratories. Protein‐profiling of bacteria using this technique has accelerated the identification of pathogens in diagnostic workflows. Recently, lipid profiling has emerged as a way to complement bacterial identification where protein‐based methods fail to provide accurate results. This study aimed to address the challenge of rapid discrimination between Escherichia coli and Shigella spp. using MALDI‐TOF MS in the negative ion mode for lipid profiling coupled with machine learning. Both E. coli and Shigella species are closely related; they share high sequence homology, reported for 16S rRNA gene sequence similarities between E. coli and Shigella spp. exceeding 99%, and a similar protein expression pattern but are epidemiologically distinct. A bacterial collection of 45 E. coli, 48 Shigella flexneri, and 62 Shigella sonnei clinical isolates were submitted to lipid profiling in negative ion mode using the MALDI Biotyper Sirius® system after treatment with mild‐acid hydrolysis (acetic acid 1% v/v for 15 min at 98°C). Spectra were then analyzed using our in‐house machine learning algorithm and top‐ranked features used for the discrimination of the bacterial species. Here, as a proof‐of‐concept, we showed that lipid profiling might have the potential to differentiate E. coli from Shigella species using the analysis of the top five ranked features obtained by MALDI‐TOF MS in the negative ion mode of the MALDI Biotyper Sirius® system. Based on this new approach, MALDI‐TOF MS analysis of lipids might help pave the way toward these goals.
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Affiliation(s)
- Jade Pizzato
- Faculty of Natural Sciences, Department of Life Sciences, MRC Centre for Molecular Bacteriology & Infection, Imperial College London, England
| | - Wenhao Tang
- Faculty of Natural Sciences, Department of Mathematics, Imperial College London, England
| | - Sandrine Bernabeu
- CHU de Bicêtre, Laboratoire de Bactériologie-Hygiène, Assistance Publique des Hôpitaux de Paris, Le Kremlin-Bicêtre, France.,INSERM UMR 1184, Team RESIST, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France.,Centre National de Référence de la Résistance aux Antibiotiques, Le Kremlin-Bicêtre, France
| | - Rémy A Bonnin
- INSERM UMR 1184, Team RESIST, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France.,Centre National de Référence de la Résistance aux Antibiotiques, Le Kremlin-Bicêtre, France
| | - Emmanuelle Bille
- Service de Microbiologie, Assistance Publique-Hôpitaux de Paris, Hôpital Necker Enfants-Malades, AP-HP Centre-Université de Paris, Paris, France
| | - Eric Farfour
- Service de Biologie Clinique, Hôpital Foch, Suresnes, France
| | - Thomas Guillard
- Université de Reims-Champagne-Ardenne, Inserm UMR-S 1250 P3Cell, SFR CAP-Santé, Laboratoire de Bactériologie-Virologie-Hygiène, Hospitalière-Parasitologie-Mycologie, Hôpital Robert Debré, CHU Reims, Reims, France
| | - Olivier Barraud
- CHU Limoges, Service de Bactériologie-Virologie-Hygiène, CIC1435, INSERM 1092, Université de Limoges, UMR, Limoges, France
| | - Vincent Cattoir
- Service de Bactériologie-Hygiène, CHU de Rennes, Rennes, France
| | - Chloe Plouzeau
- Service de Bactériologie et d'Hygiène hospitalière, Unité de microbiologie moléculaire et séquençage, CHU de Poitiers, Poitiers, France
| | - Stéphane Corvec
- Université de Nantes, CHU Nantes, Service de Bactériologie et des Contrôles Microbiologiques, INSERM, INCIT UMR 1302 F- 44000 Nantes, France
| | - Vahid Shahrezaei
- Faculty of Natural Sciences, Department of Mathematics, Imperial College London, England
| | - Laurent Dortet
- CHU de Bicêtre, Laboratoire de Bactériologie-Hygiène, Assistance Publique des Hôpitaux de Paris, Le Kremlin-Bicêtre, France.,INSERM UMR 1184, Team RESIST, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France.,Centre National de Référence de la Résistance aux Antibiotiques, Le Kremlin-Bicêtre, France
| | - Gerald Larrouy-Maumus
- Faculty of Natural Sciences, Department of Life Sciences, MRC Centre for Molecular Bacteriology & Infection, Imperial College London, England
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12
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Sun Q, Xia Y, Qin H, Zhang W, Wang J, Ning Y, Dong Y. MEF2 intervened LPS-induced acute lung injury by binding to KLF2 promoter and modulating macrophage phenotype. Int Immunopharmacol 2022; 108:108873. [DOI: 10.1016/j.intimp.2022.108873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 05/09/2022] [Accepted: 05/14/2022] [Indexed: 11/27/2022]
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13
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Cardiolipin Biosynthesis Genes Are Not Required for Salmonella enterica Serovar Typhimurium Pathogenesis in C57BL/6J Mice. Microbiol Spectr 2022; 10:e0261721. [PMID: 35638781 PMCID: PMC9241728 DOI: 10.1128/spectrum.02617-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Salmonella enterica serovar Typhimurium is an intracellular pathogen that parasitizes macrophages from within a vacuole. The vacuolar environment prompts the bacterium to regulate the lipid composition of the outer membrane (OM), and this influences host inflammation. S. Typhimurium regulates the levels of acidic glycerophospholipids known as cardiolipins (CL) within the OM, and mitochondrial CL molecules can prime and activate host inflammasomes. However, the contribution of S. Typhimurium’s CL biosynthesis genes to intracellular survival, inflammasome activation, and pathogenesis had not been examined. S. Typhimurium genes encode three CL synthases. Single, double, and triple mutants were constructed. Similar to other Enterobacteriaceae, ClsA is the primary CL synthase for S. Typhimurium during logarithmic growth, while ClsB and ClsC contribute CL production in stationary phase. It was necessary to delete all three genes to diminish the CL content of the envelope. Despite being devoid of CL molecules, ΔclsABC mutants were highly virulent during oral and systemic infection for C57BL/6J mice. In macrophages, ΔclsA, ΔclsB, ΔclsC, and ΔclsAC mutants behaved like the wild type, whereas ΔclsAB, ΔclsBC, and ΔclsABC mutants were attenuated and elicited reduced amounts of secreted interleukin-1 beta (IL-1β), IL-18, and lactate dehydrogenase. Hence, when clsA and clsC are deleted, clsB is necessary and sufficient to promote intracellular survival and inflammasome activation. Similarly, when clsB is deleted, clsA and clsC are necessary and sufficient. Therefore, the three CL synthase genes cooperatively and redundantly influence S. Typhimurium inflammasome activation and intracellular survival in C57BL/6J mouse macrophages but are dispensable for virulence in mice. IMPORTANCESalmonella enterica serovar Typhimurium is a pathogenic Gram-negative bacterium that regulates the cardiolipin (CL) and lipopolysaccharide (LPS) composition of the outer membrane (OM) during infection. Mitochondrial CL molecules activate the inflammasome and its effector caspase-1, which initiates an inflammatory process called pyroptosis. Purified bacterial CL molecules also influence LPS activation of Toll-like receptor 4 (Tlr4). S. Typhimurium resides within macrophage vacuoles and activates Tlr4 and the inflammasome during infection. However, the contribution of the three bacterial CL synthase genes (cls) to microbial pathogenesis and inflammation had not been tested. This study supports that the genes encoding the CL synthases work coordinately to promote intracellular survival in macrophages and to activate the inflammasome but do not influence inflammatory cytokine production downstream of Tlr4 or virulence in C57BL/6J mice. The macrophage phenotypes are not directly attributable to CL production but are caused by deleting specific combinations of cls gene products.
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14
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Nasser A, Mosadegh M, Azimi T, Shariati A. Molecular mechanisms of Shigella effector proteins: a common pathogen among diarrheic pediatric population. Mol Cell Pediatr 2022; 9:12. [PMID: 35718793 PMCID: PMC9207015 DOI: 10.1186/s40348-022-00145-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 05/06/2022] [Indexed: 12/16/2022] Open
Abstract
Different gastrointestinal pathogens cause diarrhea which is a very common problem in children aged under 5 years. Among bacterial pathogens, Shigella is one of the main causes of diarrhea among children, and it accounts for approximately 11% of all deaths among children aged under 5 years. The case-fatality rates for Shigella among the infants and children aged 1 to 4 years are 13.9% and 9.4%, respectively. Shigella uses unique effector proteins to modulate intracellular pathways. Shigella cannot invade epithelial cells on the apical site; therefore, it needs to pass epithelium through other cells rather than the epithelial cell. After passing epithelium, macrophage swallows Shigella, and the latter should prepare itself to exhibit at least two types of responses: (I) escaping phagocyte and (II) mediating invasion of and injury to the recurrent PMN. The presence of PMN and invitation to a greater degree resulted in gut membrane injuries and greater bacterial penetration. Infiltration of Shigella to the basolateral space mediates (A) cell attachment, (B) cell entry, (C) evasion of autophagy recognition, (D) vacuole formation and and vacuole rapture, (E) intracellular life, (F) Shiga toxin, and (G) immune response. In this review, an attempt is made to explain the role of each factor in Shigella infection.
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Affiliation(s)
- Ahmad Nasser
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mehrdad Mosadegh
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Taher Azimi
- Department of Bacteriology & Virology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
| | - Aref Shariati
- Molecular and medicine research center, Khomein University of Medical Sciences, Khomein, Iran
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15
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Kwak G, Cheng J, Kim H, Song S, Lee SJ, Yang Y, Jeong JH, Lee JE, Messersmith PB, Kim SH. Sustained Exosome-Guided Macrophage Polarization Using Hydrolytically Degradable PEG Hydrogels for Cutaneous Wound Healing: Identification of Key Proteins and MiRNAs, and Sustained Release Formulation. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2200060. [PMID: 35229462 DOI: 10.1002/smll.202200060] [Citation(s) in RCA: 49] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 01/27/2022] [Indexed: 05/24/2023]
Abstract
Macrophages (Mφs) are characterized by remarkable plasticity, an essential component of chronic inflammation. Thus, an appropriate and timely transition from proinflammatory (M1) to anti-inflammatory (M2) Mφs during wound healing is vital to promoting resolution of acute inflammation and enhancing tissue repair. Herein, exosomes derived from M2-Mφs (M2-Exos), which contain putative key regulators driving Mφ polarization, are used as local microenvironmental cues to induce reprogramming of M1-Mφs toward M2-Mφs for effective wound management. As an injectable controlled release depot for exosomes, hydrolytically degradable poly(ethylene glycol) (PEG) hydrogels (Exogels) are designed and employed for encapsulating M2-Exos to maximize their therapeutic effects in cutaneous wound healing. The degradation time of the hydrogels is adjustable from 6 days or up to 27 days by controlling the crosslinking density and tightness. The localization of M2-Exos leads to a successful local transition from M1-Mφs to M2-Mφs within the lesion for more than 6 days, followed by enhanced therapeutic effects including rapid wound closure and increased healing quality in an animal model for cutaneous wound healing. Collectively, the hydrolytically degradable PEG hydrogel-based exosome delivery system may serve as a potential tool in regulating local polarization state of Mφs, which is crucial for tissue homeostasis and wound repair.
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Affiliation(s)
- Gijung Kwak
- Center for Theragnosis, Biomedical Research Division, Korea Institute of Science and Technology, Hwarangro 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea
| | - Jing Cheng
- Departments of Bioengineering and Materials Science and Engineering, University of California, Berkeley, 210 Hearst Mining Building, Berkeley, CA, 94720, USA
| | - Hyosuk Kim
- Center for Theragnosis, Biomedical Research Division, Korea Institute of Science and Technology, Hwarangro 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea
| | - Sukyung Song
- Center for Theragnosis, Biomedical Research Division, Korea Institute of Science and Technology, Hwarangro 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea
- Department of Biosystems & Biotechnology, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Su Jin Lee
- Center for Theragnosis, Biomedical Research Division, Korea Institute of Science and Technology, Hwarangro 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea
| | - Yoosoo Yang
- Center for Theragnosis, Biomedical Research Division, Korea Institute of Science and Technology, Hwarangro 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea
| | - Ji Hoon Jeong
- School of Pharmacy, Sungkyunkwan University, Suwon, 440-746, Republic of Korea
| | - Ji Eun Lee
- Center for Theragnosis, Biomedical Research Division, Korea Institute of Science and Technology, Hwarangro 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea
| | - Phillip B Messersmith
- Departments of Bioengineering and Materials Science and Engineering, University of California, Berkeley, 210 Hearst Mining Building, Berkeley, CA, 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Sun Hwa Kim
- Center for Theragnosis, Biomedical Research Division, Korea Institute of Science and Technology, Hwarangro 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea
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16
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Xia B, Wu W, Fang W, Wen X, Xie J, Zhang H. Heat stress-induced mucosal barrier dysfunction is potentially associated with gut microbiota dysbiosis in pigs. ANIMAL NUTRITION (ZHONGGUO XU MU SHOU YI XUE HUI) 2022; 8:289-299. [PMID: 35024466 PMCID: PMC8717382 DOI: 10.1016/j.aninu.2021.05.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 05/12/2021] [Accepted: 05/18/2021] [Indexed: 02/07/2023]
Abstract
Heat stress (HS) can be detrimental to the gut health of swine. Many negative outcomes induced by HS are increasingly recognized as including modulation of intestinal microbiota. In turn, the intestinal microbiota is a unique ecosystem playing a critical role in mediating the host stress response. Therefore, we aimed to characterize gut microbiota of pigs’ exposure to short-term HS, to explore a possible link between the intestinal microbiota and HS-related changes, including serum cytokines, oxidation status, and intestinal epithelial barrier function. Our findings showed that HS led to intestinal morphological and integrity changes (villus height, serum diamine oxidase [DAO], serum D-lactate and the relative expressions of tight junction proteins), reduction of serum cytokines (interleukin [IL]-8, IL-12, interferon-gamma [IFN-γ]), and antioxidant activity (higher glutathione [GSH] and malondialdehyde [MDA] content, and lower superoxide dismutase [SOD]). Also, 16S rRNA sequencing analysis revealed that although there was no difference in microbial α-diversity, some HS-associated composition differences were revealed in the ileum and cecum, which partly led to an imbalance in the production of short-chain fatty acids including propionate acid and valerate acid. Relevance networks revealed that HS-derived changes in bacterial genera and microbial metabolites, such as Chlamydia, Lactobacillus, Succinivibrio, Bifidobacterium, Lachnoclostridium, and propionic acid, were correlated with oxidative stress, intestinal barrier dysfunction, and inflammation in pigs. Collectively, our observations suggest that intestinal damage induced by HS is probably partly related to the gut microbiota dysbiosis, though the underlying mechanism remains to be fully elucidated.
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Affiliation(s)
- Bing Xia
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Weida Wu
- Institute of Quality Standard and Testing Technology for Agro-Products, Key Laboratory of Agro-Product Quality and Safety, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Wei Fang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.,Academy of State Administration of Grain, Beijing, 100037, China
| | - Xiaobin Wen
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Jingjing Xie
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Hongfu Zhang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
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17
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Woida PJ, Satchell KJF. Bacterial Toxin and Effector Regulation of Intestinal Immune Signaling. Front Cell Dev Biol 2022; 10:837691. [PMID: 35252199 PMCID: PMC8888934 DOI: 10.3389/fcell.2022.837691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 01/24/2022] [Indexed: 11/13/2022] Open
Abstract
The host immune response is highly effective to detect and clear infecting bacterial pathogens. Given the elaborate surveillance systems of the host, it is evident that in order to productively infect a host, the bacteria often coordinate virulence factors to fine-tune the host response during infection. These coordinated events can include either suppressing or activating the signaling pathways that control the immune response and thereby promote bacterial colonization and infection. This review will cover the surveillance and signaling systems for detection of bacteria in the intestine and a sample of the toxins and effectors that have been characterized that cirumvent these signaling pathways. These factors that promote infection and disease progression have also been redirected as tools or therapeutics. Thus, these toxins are enemies deployed to enhance infection, but can also be redeployed as allies to enable research and protect against infection.
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18
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Shigella Outer Membrane Vesicles as Promising Targets for Vaccination. Int J Mol Sci 2022; 23:ijms23020994. [PMID: 35055181 PMCID: PMC8781765 DOI: 10.3390/ijms23020994] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 01/11/2022] [Accepted: 01/14/2022] [Indexed: 12/17/2022] Open
Abstract
The clinical symptoms of shigellosis, a gastrointestinal infection caused by Shigella spp. range from watery diarrhea to fulminant dysentery. Endemic infections, particularly among children in developing countries, represent the majority of clinical cases. The situation is aggravated due to the high mortality rate of shigellosis, the rapid dissemination of multi-resistant Shigella strains and the induction of only serotype-specific immunity. Thus, infection prevention due to vaccination, encompassing as many of the circulating serotypes as possible, has become a topic of interest. However, vaccines have turned out to be ineffective so far. Outer membrane vesicles (OMVs) are promising novel targets for vaccination. OMVs are constitutively secreted by Gram-negative bacteria including Shigella during growth. They are composed of soluble luminal portions and an insoluble membrane and can contain toxins, bioactive periplasmic and cytoplasmic (lipo-) proteins, (phospho-) lipids, nucleic acids and/or lipopolysaccharides. Thus, OMVs play an important role in bacterial cell–cell communication, growth, survival and pathogenesis. Furthermore, they modulate the secretion and transport of biomolecules, the stress response, antibiotic resistance and immune responses of the host. Thus, OMVs serve as novel secretion machinery. Here, we discuss the current literature and highlight the properties of OMVs as potent vaccine candidates because of their immunomodulatory, antigenic and adjuvant properties.
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19
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Tummers B, Green DR. The evolution of regulated cell death pathways in animals and their evasion by pathogens. Physiol Rev 2022; 102:411-454. [PMID: 34898294 PMCID: PMC8676434 DOI: 10.1152/physrev.00002.2021] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 09/01/2021] [Accepted: 09/01/2022] [Indexed: 12/21/2022] Open
Abstract
The coevolution of host-pathogen interactions underlies many human physiological traits associated with protection from or susceptibility to infections. Among the mechanisms that animals utilize to control infections are the regulated cell death pathways of pyroptosis, apoptosis, and necroptosis. Over the course of evolution these pathways have become intricate and complex, coevolving with microbes that infect animal hosts. Microbes, in turn, have evolved strategies to interfere with the pathways of regulated cell death to avoid eradication by the host. Here, we present an overview of the mechanisms of regulated cell death in Animalia and the strategies devised by pathogens to interfere with these processes. We review the molecular pathways of regulated cell death, their roles in infection, and how they are perturbed by viruses and bacteria, providing insights into the coevolution of host-pathogen interactions and cell death pathways.
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Affiliation(s)
- Bart Tummers
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Douglas R Green
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, Tennessee
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20
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Guo Y, Mao R, Xie Q, Cheng X, Xu T, Wang X, Du Y, Qi X. Francisella novicida Mutant XWK4 Triggers Robust Inflammasome Activation Favoring Infection. Front Cell Dev Biol 2021; 9:743335. [PMID: 34869331 PMCID: PMC8637620 DOI: 10.3389/fcell.2021.743335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Accepted: 09/29/2021] [Indexed: 11/13/2022] Open
Abstract
Bacterial infection tendentiously triggers inflammasome activation, whereas the roles of inflammasome activation in host defense against diverse infections remain unclear. Here, we identified that an ASC-dependent inflammasome activation played opposite roles in host defense against Francisella novicida wild-type (WT) U112 and mutant strain XWK4. Comparing with U112, XWK4 infection induced robust cytokine production, ASC-dependent inflammasome activation, and pyroptosis. Both AIM2 and NLRP3 were involved and played independent roles in XWK4-induced inflammasome activation. Type II interferon was partially required for XWK4-triggered inflammasome activation, which was different from type I interferon dependency in U112-induced inflammasome activation. Distinct from F. novicida U112 and Acinetobacter baumannii infection, Asc-/- mice were more resistant than WT mice response to XWK4 infection by limiting bacterial burden in vivo. The excessive inflammasome activation triggered by XWK4 infection caused dramatical cell death and pathological damage. Our study offers novel insights into mechanisms of inflammasome activation in host defense and provides potential therapeutic approach against bacterial infections and inflammatory diseases.
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Affiliation(s)
- Yu Guo
- School of Life Sciences, University of Science and Technology of China, Hefei, China.,Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Rudi Mao
- Key Laboratory for Experimental Teratology of the Ministry of Education, Advanced Medical Research Institute, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Qingqing Xie
- Key Laboratory for Experimental Teratology of the Ministry of Education, Advanced Medical Research Institute, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Xiaojie Cheng
- Key Laboratory for Experimental Teratology of the Ministry of Education, Advanced Medical Research Institute, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Tao Xu
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Xiaoyuan Wang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Yan Du
- Department of Clinical Laboratory, The First Affiliated Hospital of Kunming Medical University, Kunming, China.,Yunnan Key Laboratory of Laboratory Medicine, Kunming, China
| | - Xiaopeng Qi
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China.,Key Laboratory for Experimental Teratology of the Ministry of Education, Advanced Medical Research Institute, Cheeloo College of Medicine, Shandong University, Jinan, China.,Department of Clinical Laboratory, Qilu Hospital of Shandong University, Jinan, China
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21
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Khatun S, Appidi T, Rengan AK. The role played by bacterial infections in the onset and metastasis of cancer. CURRENT RESEARCH IN MICROBIAL SCIENCES 2021; 2:100078. [PMID: 34841367 PMCID: PMC8610348 DOI: 10.1016/j.crmicr.2021.100078] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 10/04/2021] [Accepted: 10/24/2021] [Indexed: 02/09/2023] Open
Abstract
Understanding various responses of cells towards change in their external environment, presence of other species and is important in identifying and correlating the mechanisms leading to malignant transformations and cancer development. Although uncovering and comprehending the association between bacteria and cancer is highly challenging, it promises excellent perspectives and approaches for successful cancer therapy. This review introduces various bacterial species, their virulence factors, and their role in cell transformations leading to cancer (particularly gastric, oral, colon, and breast cancer). Bacterial dysbiosis permutates host cells, causes inflammation, and results in tumorigenesis. This review explored bacterial-mediated host cell transformation causing chronic inflammation, immune receptor hyperactivation/absconding immune recognition, and genomic instability. Bacterial infections downregulate E-cadherin, leading to loosening of epithelial tight junction polarity and triggers metastasis. In addition to understanding the role of bacterial infections in cancer development, we have also reviewed the application of bacteria for cancer therapy. The emergence of bacteriotherapy combined with conventional therapies led to new and effective ways of overcoming challenges associated with available treatments. This review discusses the application of bacterial minicells, microswimmers, and outer cell membrane vesicles (OMV) for drug delivery applications.
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Affiliation(s)
- Sajmina Khatun
- Department of Biomedical Engineering, IIT Hyderabad, Kandi, Sangareddy 502284, Telangana, India
| | - Tejaswini Appidi
- Department of Biomedical Engineering, IIT Hyderabad, Kandi, Sangareddy 502284, Telangana, India
| | - Aravind Kumar Rengan
- Department of Biomedical Engineering, IIT Hyderabad, Kandi, Sangareddy 502284, Telangana, India
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22
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Oh C, Verma A, Hafeez M, Hogland B, Aachoui Y. Shigella OspC3 suppresses murine cytosolic LPS sensing. iScience 2021; 24:102910. [PMID: 34409271 PMCID: PMC8361271 DOI: 10.1016/j.isci.2021.102910] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 05/09/2021] [Accepted: 07/23/2021] [Indexed: 12/18/2022] Open
Abstract
Shigella flexneri, a cytosol-invasive gram-negative pathogen, deploys an array of type III-secreted effector proteins to evade host cell defenses. Caspase-11 and its human ortholog caspase-4 detect cytosolic lipopolysaccharide (LPS) and trigger gasdermin D-mediated pyroptosis to eliminate intra-cytoplasmic bacterial threats. However, the role of caspase-11 in combating S. flexneri is unclear. The Shigella T3SS effector OspC3 reportedly suppresses cytosolic LPS sensing by inhibiting caspase-4 but not caspase-11 activity. Surprisingly, we found that S. flexneri also uses OspC3 to inhibit murine caspase-11 activity. Mechanistically, we found that OspC3 binds only to primed caspase-11. Importantly, we demonstrate that S. flexneri employs OspC3 to prevent caspase-11-mediated pyroptosis in neutrophils, enabling bacteria to disseminate and evade clearance following intraperitoneal challenge. In contrast, S. flexneri lacking OspC3 is attenuated in a caspase-11- and gasdermin D-dependent fashion. Overall, our study reveals that OspC3 suppresses cytosolic LPS detection in a broad array of mammals. S. flexneri T3SS-secreted OspC3 suppresses cytosolic LPS sensing by caspase-11 OspC3 binds to caspase-11 in a priming-dependent manner S. flexneri employs OspC3 to prevent caspase-11-mediated pyroptosis in neutrophils Neutrophil caspase-11 is essential in defense against S. flexneri ΔOspC3 in vivo
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Affiliation(s)
- Changhoon Oh
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Ambika Verma
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Mohib Hafeez
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.,Department of Biology, University of Arkansas at Little Rock, Little Rock, AR 72204, USA
| | - Brandon Hogland
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Youssef Aachoui
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
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23
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Di Lorenzo F, Duda KA, Lanzetta R, Silipo A, De Castro C, Molinaro A. A Journey from Structure to Function of Bacterial Lipopolysaccharides. Chem Rev 2021; 122:15767-15821. [PMID: 34286971 DOI: 10.1021/acs.chemrev.0c01321] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Lipopolysaccharide (LPS) is a crucial constituent of the outer membrane of most Gram-negative bacteria, playing a fundamental role in the protection of bacteria from environmental stress factors, in drug resistance, in pathogenesis, and in symbiosis. During the last decades, LPS has been thoroughly dissected, and massive information on this fascinating biomolecule is now available. In this Review, we will give the reader a third millennium update of the current knowledge of LPS with key information on the inherent peculiar carbohydrate chemistry due to often puzzling sugar residues that are uniquely found on it. Then, we will drive the reader through the complex and multifarious immunological outcomes that any given LPS can raise, which is strictly dependent on its chemical structure. Further, we will argue about issues that still remain unresolved and that would represent the immediate future of LPS research. It is critical to address these points to complete our notions on LPS chemistry, functions, and roles, in turn leading to innovative ways to manipulate the processes involving such a still controversial and intriguing biomolecule.
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Affiliation(s)
- Flaviana Di Lorenzo
- Department of Chemical Sciences, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.,Task Force on Microbiome Studies, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy
| | - Katarzyna A Duda
- Research Center Borstel Leibniz Lung Center, Parkallee 4a, 23845 Borstel, Germany
| | - Rosa Lanzetta
- Department of Chemical Sciences, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy
| | - Alba Silipo
- Department of Chemical Sciences, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.,Task Force on Microbiome Studies, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy
| | - Cristina De Castro
- Task Force on Microbiome Studies, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.,Department of Agricultural Sciences, University of Naples Federico II, Via Università 96, 80055 Portici, Naples, Italy
| | - Antonio Molinaro
- Department of Chemical Sciences, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.,Task Force on Microbiome Studies, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.,Department of Chemistry, School of Science, Osaka University, 1-1 Osaka University Machikaneyama, Toyonaka, Osaka 560-0043, Japan
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24
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Wu BC, Olivia NA, Tembo JM, He YX, Zhang YM, Xue Y, Ye CL, Lv Y, Li WJ, Jiang LY, Huo XX, Sun ZY, Chen ZJ, Qin JC, Li AY, Park CG, Klena JD, Ding HH, Chen T. Loss of the virulence plasmid by Shigella sonnei promotes its interactions with CD207 and CD209 receptors. J Med Microbiol 2021; 70:001297. [PMID: 33591245 PMCID: PMC8346720 DOI: 10.1099/jmm.0.001297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 11/29/2020] [Indexed: 01/24/2023] Open
Abstract
Introduction. Shigella sonnei, the cause of bacillary dysentery, belongs to Gram-negative enteropathogenic bacteria. S. sonnei contains a 210 kb virulence plasmid that encodes an O-antigen gene cluster of LPSs. However, this virulence plasmid is frequently lost during replication. It is well-documented that after losing the O-antigen and becoming rough strains, the Gram-negative bacteria may express an LPS core on its surface. Previous studies have suggested that by using the LPS core, Gram-negative bacteria can interact with several C-type lectin receptors that are expressed on antigen-presenting cells (APCs).Hypothesis/Gap Statement. S. sonnei by losing the virulence plasmid may hijack APCs via the interactions of LPS-CD209/CD207.Aim. This study aimed to investigate if the S. sonnei rough strain, by losing the virulence plasmid, interacted with APCs that express C-type lectins of human CD207, human CD209a and mouse CD209b.Methodology. SDS-PAGE silver staining was used to examine the O-antigen expression of S. sonnei WT and its rough strain. Invasion assays and inhibition assays were used to examine the ability of S. sonnei WT and its rough strain to invade APCs and investigate whether CD209 and CD207 are receptors for phagocytosis of rough S. sonnei. Animal assays were used to observe the dissemination of S. sonnei.Results. S. sonnei did not express O-antigens after losing the virulence plasmid. The S. sonnei rough strain invades with APCs, including human dendritic cells (DCs) and mouse macrophages. CD209 and CD207 are receptors for phagocytosis of rough S. sonnei. Expression of the O-antigen reduces the ability of the S. sonnei rough strain to be disseminated to mesenteric lymph nodes and spleens.Conclusion. This work demonstrated that S. sonnei rough strains - by losing the virulence plasmid - invaded APCs through interactions with CD209 and CD207 receptors.
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Affiliation(s)
- Bi-cong Wu
- Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
- Henan Provincial Center for Disease Control and Prevention, Zhengzhou, Henan, PR China
| | - Njiri A. Olivia
- Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
- Department of Biological Sciences, Faculty of Science, Engineering and Technology, Chuka University, 109-60400, Kenya
| | - John Mambwe Tembo
- Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
- Department of Paediatrics & Child Health, the University of Zambia – University College London Medical School at Zambia, Lusaka, Zambia
| | - Ying-xia He
- Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
- Clinical Research Center, Wuhan Pulmonary Hospital, Wuhan, Hubei, PR China
| | - Ying-miao Zhang
- Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
- Department of Clinical Laboratory, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China
| | - Ying Xue
- Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
| | - Cheng-lin Ye
- Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
| | - Yin Lv
- Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
| | - Wen-jin Li
- Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
| | - Ling-Yu Jiang
- Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
| | - Xi-xiang Huo
- Hubei Provincial Center for Disease Control and Prevention, Wuhan, Hubei, PR China
| | - Zi-yong Sun
- Department of Laboratory Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
| | - Zhong-ju Chen
- Department of Laboratory Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
| | - Ji-chao Qin
- Key Laboratory of Hepatobiliary Surgery and Department of Hepatobiliary Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
| | - An-yi Li
- Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
| | - Chae Gyu Park
- Laboratory of Immunology, Brain Korea 21 PLUS Project for Medical Science, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - John D. Klena
- Centers for Disease Control and Prevention, Atlanta, GE, USA
| | - Hong-hui Ding
- Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
| | - Tie Chen
- Department of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Sciences and Technology, Wuhan, Hubei, PR China
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25
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Munford RS, Weiss JP, Lu M. Biochemical transformation of bacterial lipopolysaccharides by acyloxyacyl hydrolase reduces host injury and promotes recovery. J Biol Chem 2020; 295:17842-17851. [PMID: 33454018 DOI: 10.1074/jbc.rev120.015254] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 10/22/2020] [Indexed: 12/26/2022] Open
Abstract
Animals can sense the presence of microbes in their tissues and mobilize their own defenses by recognizing and responding to conserved microbial structures (often called microbe-associated molecular patterns (MAMPs)). Successful host defenses may kill the invaders, yet the host animal may fail to restore homeostasis if the stimulatory microbial structures are not silenced. Although mice have many mechanisms for limiting their responses to lipopolysaccharide (LPS), a major Gram-negative bacterial MAMP, a highly conserved host lipase is required to extinguish LPS sensing in tissues and restore homeostasis. We review recent progress in understanding how this enzyme, acyloxyacyl hydrolase (AOAH), transforms LPS from stimulus to inhibitor, reduces tissue injury and death from infection, prevents prolonged post-infection immunosuppression, and keeps stimulatory LPS from entering the bloodstream. We also discuss how AOAH may increase sensitivity to pulmonary allergens. Better appreciation of how host enzymes modify LPS and other MAMPs may help prevent tissue injury and hasten recovery from infection.
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Affiliation(s)
- Robert S Munford
- Laboratory of Clinical Immunology and Microbiology, NIAID, National Institutes of Health, Bethesda, Maryland, USA.
| | - Jerrold P Weiss
- Inflammation Program, University of Iowa, Iowa City, Iowa, USA
| | - Mingfang Lu
- Department of Immunology and Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Fudan University, Shanghai, China.
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26
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Downs KP, Nguyen H, Dorfleutner A, Stehlik C. An overview of the non-canonical inflammasome. Mol Aspects Med 2020; 76:100924. [PMID: 33187725 PMCID: PMC7808250 DOI: 10.1016/j.mam.2020.100924] [Citation(s) in RCA: 140] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 10/30/2020] [Accepted: 11/03/2020] [Indexed: 12/21/2022]
Abstract
Inflammasomes are large cytosolic multiprotein complexes assembled in response to infection and cellular stress, and are crucial for the activation of inflammatory caspases and the subsequent processing and release of pro-inflammatory mediators. While caspase-1 is activated within the canonical inflammasome, the related caspase-4 (also known as caspase-11 in mice) and caspase-5 are activated within the non-canonical inflammasome upon sensing of cytosolic lipopolysaccharide (LPS) from Gram-negative bacteria. However, the consequences of canonical and non-canonical inflammasome activation are similar. Caspase-1 promotes the processing and release of the pro-inflammatory cytokines interleukin (IL)-1β and IL-18 and the release of danger signals, as well as a lytic form of cell death called pyroptosis, whereas caspase-4, caspase-5 and caspase-11 directly promote pyroptosis through cleavage of the pore-forming protein gasdermin D (GSDMD), and trigger a secondary activation of the canonical NLRP3 inflammasome for cytokine release. Since the presence of the non-canonical inflammasome activator LPS leads to endotoxemia and sepsis, non-canonical inflammasome activation and regulation has important clinical ramifications. Here we discuss the mechanism of non-canonical inflammasome activation, mechanisms regulating its activity and its contribution to health and disease.
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Affiliation(s)
- Kevin P Downs
- Department of Pathology and Laboratory Medicine, Cedars Sinai, Los Angeles, CA, 90048, USA.
| | - Huyen Nguyen
- Department of Pathology and Laboratory Medicine, Cedars Sinai, Los Angeles, CA, 90048, USA.
| | - Andrea Dorfleutner
- Department of Pathology and Laboratory Medicine, Cedars Sinai, Los Angeles, CA, 90048, USA; Department of Biomedical Sciences, Cedars Sinai, Los Angeles, CA, 90048, USA.
| | - Christian Stehlik
- Department of Pathology and Laboratory Medicine, Cedars Sinai, Los Angeles, CA, 90048, USA; Department of Biomedical Sciences, Cedars Sinai, Los Angeles, CA, 90048, USA; Samuel Oschin Comprehensive Cancer Institute, Cedars Sinai, Los Angeles, CA, 90048, USA.
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27
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Oh C, Verma A, Aachoui Y. Caspase-11 Non-canonical Inflammasomes in the Lung. Front Immunol 2020; 11:1895. [PMID: 32973786 PMCID: PMC7472987 DOI: 10.3389/fimmu.2020.01895] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 07/14/2020] [Indexed: 12/27/2022] Open
Abstract
The airway epithelium and underlying innate immune cells comprise the first line of host defense in the lung. They recognize pathogen-associated molecular patterns (PAMPs) using membrane-bound receptors, as well as cytosolic receptors such as inflammasomes. Inflammasomes activate inflammatory caspases, which in turn process and release the inflammatory cytokines IL-1β and IL-18. Additionally, inflammasomes trigger a form of lytic cell death termed pyroptosis. One of the most important inflammasomes at the host-pathogen interface is the non-canonical caspase-11 inflammasome that responds to LPS in the cytosol. Caspase-11 is important in defense against Gram-negative pathogens, and can drive inflammatory diseases such as LPS-induced sepsis. However, pathogens can employ evasive strategies to minimize or evade host caspase-11 detection. In this review, we present a comprehensive overview of the function of the non-canonical caspase-11 inflammasome in sensing of cytosolic LPS, and its mechanism of action with particular emphasis in the role of caspase-11 in the lung. We also explore some of the strategies pathogens use to evade caspase-11.
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Affiliation(s)
- Changhoon Oh
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Ambika Verma
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Youssef Aachoui
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR, United States
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28
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An electrochemical sensor for bacterial lipopolysaccharide detection based on dual functional Cu2+-modified metal–organic framework nanoparticles. Mikrochim Acta 2020; 187:415. [DOI: 10.1007/s00604-020-04364-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 06/01/2020] [Indexed: 02/02/2023]
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29
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Demarco B, Chen KW, Broz P. Cross talk between intracellular pathogens and cell death. Immunol Rev 2020; 297:174-193. [PMID: 32567717 DOI: 10.1111/imr.12892] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 05/24/2020] [Accepted: 05/28/2020] [Indexed: 02/06/2023]
Abstract
Infections with bacterial pathogens often results in the initiation of programmed cell death as part of the host innate immune defense, or as a bacterial virulence strategy. Induction of host cell death is controlled by an elaborate network of innate immune and cell death signaling pathways and manifests in different morphologically and functionally distinct forms of death, such as apoptosis, necroptosis, NETosis and pyroptosis. The mechanism by which host cell death restricts bacterial replication is highly cell-type and context depended, but its physiological importance is highlighted the diversity of strategies bacterial pathogens use to avoid induction of cell death or to block cell death signaling pathways. In this review, we discuss the latest insights into how bacterial pathogens elicit and manipulate cell death signaling, how different forms of cell death kill or restrict bacteria and how cell death and innate immune pathway cross talk to guard against pathogen-induced inhibition of host cell death.
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Affiliation(s)
- Benjamin Demarco
- Department of Biochemistry, University of Lausanne, Epalinges, Switzerland
| | - Kaiwen W Chen
- Department of Biochemistry, University of Lausanne, Epalinges, Switzerland
| | - Petr Broz
- Department of Biochemistry, University of Lausanne, Epalinges, Switzerland
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30
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Li LH, Chen TL, Chiu HW, Hsu CH, Wang CC, Tai TT, Ju TC, Chen FH, Chernikov OV, Tsai WC, Hua KF. Critical Role for the NLRP3 Inflammasome in Mediating IL-1β Production in Shigella sonnei-Infected Macrophages. Front Immunol 2020; 11:1115. [PMID: 32582195 PMCID: PMC7283925 DOI: 10.3389/fimmu.2020.01115] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Accepted: 05/07/2020] [Indexed: 12/24/2022] Open
Abstract
Shigella is one of the leading bacterial causes of diarrhea worldwide, affecting more than 165 million people annually. Among the serotypes of Shigella, Shigella sonnei is physiologically unique and endemic in human immunodeficiency virus-infected men who have sex with men. The NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome, a protein complex composed of NLRP3, apoptosis-associated speck-like protein, and caspase-1, recognizes, and responds to pathogen infection and diverse sterile host-derived or environmental danger signals to induce IL-1β and IL-18 production. Although the Shigella flexneri-mediated activation of the NLRP3 inflammasome has been reported, the effect of S. sonnei on NLRP3 inflammasome activation remains unclear. We found that S. sonnei induced IL-1β production through NLRP3-dependent pathways in lipopolysaccharide-primed macrophages. A mechanistic study revealed that S. sonnei induced IL-1β production through P2X7 receptor-mediated potassium efflux, reactive oxygen species generation, lysosomal acidification, and mitochondrial damage. In addition, the phagocytosis of viable S. sonnei was important for IL-1β production. Furthermore, we demonstrated that NLRP3 negatively regulated phagocytosis and the bactericidal activity of macrophages against S. sonnei. These findings provide mechanistic insight into the activation of the NLRP3 inflammasome by S. sonnei in macrophages.
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Affiliation(s)
- Lan-Hui Li
- Department of Laboratory Medicine, Linsen, Chinese Medicine and Kunming Branch, Taipei City Hospital, Taipei, Taiwan.,Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Tzu-Ling Chen
- Department of Laboratory Medicine, Linsen, Chinese Medicine and Kunming Branch, Taipei City Hospital, Taipei, Taiwan.,Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Hsiao-Wen Chiu
- Department of Biotechnology and Animal Science, National Ilan University, Ilan, Taiwan
| | - Chung-Hua Hsu
- Department of Laboratory Medicine, Linsen, Chinese Medicine and Kunming Branch, Taipei City Hospital, Taipei, Taiwan.,Institute of Traditional Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Chien-Chun Wang
- Infectious Disease Division, Linsen, Chinese Medicine and Kunming Branch, Taipei City Hospital, Taipei, Taiwan
| | - Tzu-Ting Tai
- Department of Biotechnology and Animal Science, National Ilan University, Ilan, Taiwan
| | - Tz-Chuen Ju
- Department of Animal Science and Biotechnology, Tunghai University, Taichung, Taiwan
| | - Fang-Hsin Chen
- Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Oleg V Chernikov
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry FEB RAS, Vladivostok, Russia
| | - Wen-Chiuan Tsai
- Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Kuo-Feng Hua
- Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.,Department of Biotechnology and Animal Science, National Ilan University, Ilan, Taiwan.,Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan
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31
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Sanchez‐Garrido J, Slater SL, Clements A, Shenoy AR, Frankel G. Vying for the control of inflammasomes: The cytosolic frontier of enteric bacterial pathogen-host interactions. Cell Microbiol 2020; 22:e13184. [PMID: 32185892 PMCID: PMC7154749 DOI: 10.1111/cmi.13184] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 01/13/2020] [Accepted: 01/30/2020] [Indexed: 12/13/2022]
Abstract
Enteric pathogen-host interactions occur at multiple interfaces, including the intestinal epithelium and deeper organs of the immune system. Microbial ligands and activities are detected by host sensors that elicit a range of immune responses. Membrane-bound toll-like receptors and cytosolic inflammasome pathways are key signal transducers that trigger the production of pro-inflammatory molecules, such as cytokines and chemokines, and regulate cell death in response to infection. In recent years, the inflammasomes have emerged as a key frontier in the tussle between bacterial pathogens and the host. Inflammasomes are complexes that activate caspase-1 and are regulated by related caspases, such as caspase-11, -4, -5 and -8. Importantly, enteric bacterial pathogens can actively engage or evade inflammasome signalling systems. Extracellular, vacuolar and cytosolic bacteria have developed divergent strategies to subvert inflammasomes. While some pathogens take advantage of inflammasome activation (e.g. Listeria monocytogenes, Helicobacter pylori), others (e.g. E. coli, Salmonella, Shigella, Yersinia sp.) deploy a range of virulence factors, mainly type 3 secretion system effectors, that subvert or inhibit inflammasomes. In this review we focus on inflammasome pathways and their immune functions, and discuss how enteric bacterial pathogens interact with them. These studies have not only shed light on inflammasome-mediated immunity, but also the exciting area of mammalian cytosolic immune surveillance.
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Affiliation(s)
| | | | | | - Avinash R. Shenoy
- Department of Infectious Disease, MRC Centre for Molecular Bacteriology & InfectionImperial College LondonLondonUK
| | - Gad Frankel
- Department of Life SciencesImperial College LondonLondonUK
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32
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Lacey CA, Miao EA. Programmed Cell Death in the Evolutionary Race against Bacterial Virulence Factors. Cold Spring Harb Perspect Biol 2020; 12:cshperspect.a036459. [PMID: 31501197 DOI: 10.1101/cshperspect.a036459] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Innate immune sensors can recognize when host cells are irrevocably compromised by pathogens, and in response can trigger programmed cell death (pyroptosis, apoptosis, and necroptosis). Innate sensors can directly bind microbial ligands; for example, NAIP/NLRC4 detects flagellin/rod/needle, whereas caspase-11 detects lipopolysaccharide. Other sensors are guards that monitor normal function of cellular proteins; for instance, pyrin monitors Rho GTPases, whereas caspase-8 and receptor-interacting protein kinase (RIPK)3 guards RIPK1 transcriptional signaling. Some proteins that need to be guarded can be duplicated as decoy domains, as seen in the integrated decoy domains within NLRP1 that watch for microbial attack. Here, we discuss the evolutionary battle between pathogens and host innate immune sensors/guards, illustrated by the Red Queen hypothesis. We discuss in depth four pathogens, and how they either fail in this evolutionary race (Chromobacterium violaceum, Burkholderia thailandensis), or how the evolutionary race generates increasingly complex virulence factors and host innate immune signaling pathways (Yersinia species, and enteropathogenic Escherichia coli [EPEC]).
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Affiliation(s)
- Carolyn A Lacey
- Department of Microbiology and Immunology, Center for Gastrointestinal Biology and Disease, and Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Edward A Miao
- Department of Microbiology and Immunology, Center for Gastrointestinal Biology and Disease, and Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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33
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Mukhopadhyay S, Ganguli S, Chakrabarti S. <em>Shigella</em> pathogenesis: molecular and computational insights. AIMS MOLECULAR SCIENCE 2020. [DOI: 10.3934/molsci.2020007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
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34
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Cytosolic Gram-negative bacteria prevent apoptosis by inhibition of effector caspases through lipopolysaccharide. Nat Microbiol 2019; 5:354-367. [PMID: 31873204 DOI: 10.1038/s41564-019-0620-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 10/24/2019] [Indexed: 02/08/2023]
Abstract
The cytosolic appearance and propagation of bacteria cause overwhelming cellular stress responses that induce apoptosis under normal conditions. Therefore, successful bacterial colonization depends on the ability of intracellular pathogens to block apoptosis and to safeguard bacterial replicative niches. Here, we show that the cytosolic Gram-negative bacterium Shigella flexneri stalls apoptosis by inhibiting effector caspase activity. Our data identified lipopolysaccharide (LPS) as a bona fide effector caspase inhibitor that directly binds caspases by involving its O-antigen (O Ag) moiety. Bacterial strains that lacked the O Ag or failed to replicate within the cytosol were incapable of blocking apoptosis and exhibited reduced virulence in a murine model of bacterial infection. Our findings demonstrate how Shigella inhibits pro-apoptotic caspase activity, effectively delays coordinated host-cell demise and supports its intracellular propagation. Next to the recently discovered pro-inflammatory role of cytosolic LPS, our data reveal a distinct mode of LPS action that, through the disruption of the early coordinated non-lytic cell death response, ultimately supports the inflammatory breakdown of infected cells at later time points.
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35
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Tran ENH, Day CJ, Poole J, Jennings MP, Morona R. Specific blood group antibodies inhibit Shigella flexneri interaction with human cells in the absence of spinoculation. Biochem Biophys Res Commun 2019; 521:131-136. [PMID: 31630794 DOI: 10.1016/j.bbrc.2019.10.091] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 10/10/2019] [Indexed: 10/25/2022]
Abstract
The classical models of investigating Shigella flexneri adherence and invasion of tissue culture cells involve either bacterial centrifugation (spinoculation) or the use of AfaE adhesin to overcome the low infection rate observed in vitro. However clinically, S. flexneri clearly adheres and invades the human colon in the absence of 'spinoculation'. Additionally, certain S. flexneri tissue cell based assays (e.g. plaque assays and infection of T84 epithelial cells on Transwells®), do not require spinoculation. In the absence of spinoculation, we recently showed that glycan-glycan interactions play an important role in S. flexneri interaction with host cells, and that in particular the S. flexneri 2a lipopolysaccharide O antigen glycan has a high affinity for the blood group A glycan. During the investigation of the effect of blood group A antibodies on S. flexneri interaction with cells, we discovered that Panc-1 cells exhibited a high rate of infection in the absence of spinoculation. Select blood group A antibodies inhibited invasion of Panc-1 cells, and adherence to T84 cells. The use of Panc-1 cells represents a simplified model to study S. flexneri pathogenesis and does not require either spinoculation or exogenous adhesins.
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Affiliation(s)
- Elizabeth Ngoc Hoa Tran
- School of Biological Sciences, Department of Molecular & Biomedical Science, Research Centre for Infectious Diseases, University of Adelaide, Adelaide, 5005, Australia
| | - Christopher J Day
- Institute for Glycomics, Griffith University Gold Coast Campus, Queensland, 4222, Australia
| | - Jessica Poole
- Institute for Glycomics, Griffith University Gold Coast Campus, Queensland, 4222, Australia
| | - Michael P Jennings
- Institute for Glycomics, Griffith University Gold Coast Campus, Queensland, 4222, Australia
| | - Renato Morona
- School of Biological Sciences, Department of Molecular & Biomedical Science, Research Centre for Infectious Diseases, University of Adelaide, Adelaide, 5005, Australia.
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36
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Sperandeo P, Polissi A, De Fabiani E. Fat Matters for Bugs: How Lipids and Lipid Modifications Make the Difference in Bacterial Life. EUR J LIPID SCI TECH 2019. [DOI: 10.1002/ejlt.201900204] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Paola Sperandeo
- Dipartimento di Scienze Farmacologiche e BiomolecolariUniversità degli Studi di MilanoVia Balzaretti 920133MilanoItaly
| | - Alessandra Polissi
- Dipartimento di Scienze Farmacologiche e BiomolecolariUniversità degli Studi di MilanoVia Balzaretti 920133MilanoItaly
| | - Emma De Fabiani
- Dipartimento di Scienze Farmacologiche e BiomolecolariUniversità degli Studi di MilanoVia Balzaretti 920133MilanoItaly
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37
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Qian C, Yun Z, Yao Y, Cao M, Liu Q, Hu S, Zhang S, Luo D. Heterogeneous macrophages: Supersensors of exogenous inducing factors. Scand J Immunol 2019; 90:e12768. [PMID: 31002413 PMCID: PMC6852148 DOI: 10.1111/sji.12768] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 04/01/2019] [Accepted: 04/11/2019] [Indexed: 12/14/2022]
Abstract
As heterogeneous immune cells, macrophages mount effective responses to various internal and external changes during disease progression. Macrophage polarization, rather than macrophage heterogenization, is often used to describe the functional differences between macrophages. While macrophage polarization partially contributes to heterogeneity, it does not completely explain the concept of macrophage heterogeneity. At the same time, there are abundant and sophisticated endogenous and exogenous substances that can affect macrophage heterogeneity. While the research on endogenous factors has been systematically reviewed, the findings on exogenous factors have not been well summarized. Hence, we reviewed the characteristics and inducing factors of heterogeneous macrophages to reveal their functional plasticity as well as their targeting manoeuvreability. In the process of constructing and analysing a network organized by disease-related cells and molecules, paying more attention to heterogeneous macrophages as mediators of this network may help to explore a novel entry point for early prevention of and intervention in disease.
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Affiliation(s)
- Caiyun Qian
- School of Basic Medical Sciences, Nanchang University, Nanchang, Jiangxi, China
| | - Zehui Yun
- Queen Mary School, Nanchang University, Nanchang, Jiangxi, China
| | - Yudi Yao
- School of Basic Medical Sciences, Nanchang University, Nanchang, Jiangxi, China
| | - Minghua Cao
- School of Basic Medical Sciences, Nanchang University, Nanchang, Jiangxi, China
| | - Qiang Liu
- School of Medicine, Nanchang University, Nanchang, Jiangxi, China
| | - Song Hu
- Queen Mary School, Nanchang University, Nanchang, Jiangxi, China
| | - Shuhua Zhang
- Jiangxi Cardiovascular Research Institute, Jiangxi Provincial People's Hospital, Affiliated to Nanchang University, Nanchang, Jiangxi, China
| | - Daya Luo
- School of Basic Medical Sciences, Nanchang University, Nanchang, Jiangxi, China.,Affiliated Infectious Disease Hospital, Nanchang University, Nanchang, Jiangxi, China
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38
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Abstract
ABSTRACT
Shigella
is a genus of Gram-negative enteropathogens that have long been, and continue to be, an important public health concern worldwide. Over the past several decades,
Shigella
spp. have also served as model pathogens in the study of bacterial pathogenesis, and
Shigella flexneri
has become one of the best-studied pathogens on a molecular, cellular, and tissue level. In the arms race between
Shigella
and the host immune system,
Shigella
has developed highly sophisticated mechanisms to subvert host cell processes in order to promote infection, escape immune detection, and prevent bacterial clearance. Here, we give an overview of
Shigella
pathogenesis while highlighting innovative techniques and methods whose application has significantly advanced our understanding of
Shigella
pathogenesis in recent years.
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Human Intestinal Enteroids as a Model System of Shigella Pathogenesis. Infect Immun 2019; 87:IAI.00733-18. [PMID: 30642906 DOI: 10.1128/iai.00733-18] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 01/06/2019] [Indexed: 01/01/2023] Open
Abstract
The enteric bacterium and intracellular human pathogen Shigella causes hundreds of millions of cases of the diarrheal disease shigellosis per year worldwide. Shigella is acquired by ingestion of contaminated food or water; upon reaching the colon, the bacteria invade colonic epithelial cells, replicate intracellularly, spread to adjacent cells, and provoke an intense inflammatory response. There is no animal model that faithfully recapitulates human disease; thus, cultured cells have been used to model Shigella pathogenesis. However, the use of transformed cells in culture does not provide the same environment to the bacteria as the normal human intestinal epithelium. Recent advances in tissue culture now enable the cultivation of human intestinal enteroids (HIEs), which are derived from human intestinal stem cells, grown ex vivo, and then differentiated into "mini-intestines." Here, we demonstrate that HIEs can be used to model Shigella pathogenesis. We show that Shigella flexneri invades polarized HIE monolayers preferentially via the basolateral surface. After S. flexneri invades HIE monolayers, S. flexneri replicates within HIE cells and forms actin tails. S. flexneri also increases the expression of HIE proinflammatory signals and the amino acid transporter SLC7A5. Finally, we demonstrate that disruption of HIE tight junctions enables S. flexneri invasion via the apical surface.
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40
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Liu C, Luo J, Xue RY, Guo L, Nie L, Li S, Ji L, Ma CJ, Chen DQ, Miao K, Zou QM, Li HB. The mucosal adjuvant effect of plant polysaccharides for induction of protective immunity against Helicobacter pylori infection. Vaccine 2019; 37:1053-1061. [DOI: 10.1016/j.vaccine.2018.12.066] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 12/22/2018] [Accepted: 12/31/2018] [Indexed: 12/26/2022]
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41
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Ledov VA, Golovina ME, Markina AA, Knirel YA, L'vov VL, Kovalchuk AL, Aparin PG. Highly homogenous tri-acylated S-LPS acts as a novel clinically applicable vaccine against Shigella flexneri 2a infection. Vaccine 2019; 37:1062-1072. [PMID: 30670300 DOI: 10.1016/j.vaccine.2018.12.067] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 12/08/2018] [Accepted: 12/30/2018] [Indexed: 12/24/2022]
Abstract
Shigellosis, a major cause of diarrhea worldwide, exhibits high morbidity and mortality in children. Specificity of Shigella immunity is determined by the structure of the main protective O-antigen polysaccharide component incorporated into the lipopolysaccharide (LPS) molecule. Endotoxicity, however, precludes LPS clinical use. Thus, there is still no vaccine against the most prevalent shigellosis species (serotype S. flexneri 2a), despite ongoing efforts focused on inducing serotype-specific immunity. As LPS is highly heterogenous, we hypothesized that more homogenous pools of LPS might be less toxic. We developed a method to generate a homogenous S. flexneri 2a LPS subfraction, Ac3-S-LPS, containing long chain O-specific polysaccharide (S-LPS) and mainly tri-acylated lipid A, with no penta- and hexa-acylated, and rare tetra-acylated lipid A. Ac3-S-LPS had dramatically reduced pyrogenicity and protected guinea pigs from shigellosis. In volunteers, 50 µg of injected Ac3-S-LPS vaccine was safe, with low pyrogenicity, no severe and few minor adverse events, and did not induce pro-inflammatory cytokines. In spite of the profound lipid A modification, the vaccine induced a prevalence of IgG and IgA antibodies. Thus, we have developed the first safe immunogenic LPS-based vaccine candidate for human administration. Homogenous underacetylated LPSs may also be useful for treating other LPS-driven human diseases. Clinical trial registry: http://grls.rosminzdrav.ru/.
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Affiliation(s)
- Vladimir A Ledov
- Laboratory of Carbohydrate Vaccines, National Research Center-Institute of Immunology, Federal Medical Biological Agency of Russia, 24, Kashirskoe Shosse, Moscow 115478, Russia
| | - Marina E Golovina
- Laboratory of Carbohydrate Vaccines, National Research Center-Institute of Immunology, Federal Medical Biological Agency of Russia, 24, Kashirskoe Shosse, Moscow 115478, Russia
| | - Anna A Markina
- Laboratory of Carbohydrate Vaccines, National Research Center-Institute of Immunology, Federal Medical Biological Agency of Russia, 24, Kashirskoe Shosse, Moscow 115478, Russia
| | - Yuriy A Knirel
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47, Leninsky Prospect, Moscow 117913, Russia
| | - Vyacheslav L L'vov
- Laboratory of Preparative Biochemistry, National Research Center-Institute of Immunology, Federal Medical Biological Agency of Russia, 24, Kashirskoe Shosse, Moscow 115478, Russia
| | - Alexander L Kovalchuk
- The Virology and Cellular Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, NIH, Rockville, MD 20852, United States
| | - Petr G Aparin
- Laboratory of Carbohydrate Vaccines, National Research Center-Institute of Immunology, Federal Medical Biological Agency of Russia, 24, Kashirskoe Shosse, Moscow 115478, Russia.
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42
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Abstract
Gram-negative bacteria have an outer membrane that is positioned at the frontline of the cell's interaction with the environment and that serves as a barrier against noxious molecules including many antibiotics. This protective function mainly relies on lipopolysaccharide, a complex glycolipid located in the outer leaflet of the outer membrane. In this chapter we will first summarize lipopolysaccharide structure, functions and biosynthetic pathway and then we will discuss how it is transported and assembled to the cell surface. This is a remarkably complex process, as amphipathic lipopolysaccharide molecules must traverse three different cellular compartments to reach their final destination.
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43
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Role of a fluid-phase PRR in fighting an intracellular pathogen: PTX3 in Shigella infection. PLoS Pathog 2018; 14:e1007469. [PMID: 30532257 PMCID: PMC6317801 DOI: 10.1371/journal.ppat.1007469] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 01/03/2019] [Accepted: 11/15/2018] [Indexed: 12/31/2022] Open
Abstract
Shigella spp. are pathogenic bacteria that cause bacillary dysentery in humans by invading the colonic and rectal mucosa where they induce dramatic inflammation. Here, we have analyzed the role of the soluble PRR Pentraxin 3 (PTX3), a key component of the humoral arm of innate immunity. Mice that had been intranasally infected with S. flexneri were rescued from death by treatment with recombinant PTX3. In vitro PTX3 exerts the antibacterial activity against Shigella, impairing epithelial cell invasion and contributing to the bactericidal activity of serum. PTX3 is produced upon LPS-TLR4 stimulation in accordance with the lipid A structure of Shigella. In the plasma of infected patients, the level of PTX3 amount only correlates strongly with symptom severity. These results signal PTX3 as a novel player in Shigella pathogenesis and its potential role in fighting shigellosis. Finally, we suggest that the plasma level of PTX3 in shigellosis patients could act as a biomarker for infection severity. Soluble pattern recognition molecules, PRMs, are components of the humoral arm of innate immunity. The long pentraxin 3, PTX3, is a prototypic soluble PRM that is produced in response to primary inflammatory signals. Shigella spp. are human entero-pathogens which invade colonic and rectal mucosa where they cause deleterious inflammation. We show that PTX3 acts as an ante-antibody and contributes to the clearance of extracellular Shigella. As a countermeasure, Shigella uses invasiveness and low-inflammatory LPS to control PTX3 release in infected cells. This study highlights that the extracellular phase of the invasion process can be considered the “Achille heels” of Shigella pathogenesis.
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44
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Lembo-Fazio L, Billod JM, Di Lorenzo F, Paciello I, Pallach M, Vaz-Francisco S, Holgado A, Beyaert R, Fresno M, Shimoyama A, Lanzetta R, Fukase K, Gully D, Giraud E, Martín-Santamaría S, Bernardini ML, Silipo A. Bradyrhizobium Lipid A: Immunological Properties and Molecular Basis of Its Binding to the Myeloid Differentiation Protein-2/Toll-Like Receptor 4 Complex. Front Immunol 2018; 9:1888. [PMID: 30154796 PMCID: PMC6102379 DOI: 10.3389/fimmu.2018.01888] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 07/31/2018] [Indexed: 11/24/2022] Open
Abstract
Lipopolysaccharides (LPS) are potent activator of the innate immune response through the binding to the myeloid differentiation protein-2 (MD-2)/toll-like receptor 4 (TLR4) receptor complexes. Although a variety of LPSs have been characterized so far, a detailed molecular description of the structure–activity relationship of the lipid A part has yet to be clarified. Photosynthetic Bradyrhizobium strains, symbiont of Aeschynomene legumes, express distinctive LPSs bearing very long-chain fatty acids with a hopanoid moiety covalently linked to the lipid A region. Here, we investigated the immunological properties of LPSs isolated from Bradyrhizobium strains on both murine and human immune systems. We found that they exhibit a weak agonistic activity and, more interestingly, a potent inhibitory effect on MD-2/TLR4 activation exerted by toxic enterobacterial LPSs. By applying computational modeling techniques, we also furnished a plausible explanation for the Bradyrhizobium LPS inhibitory activity at atomic level, revealing that its uncommon lipid A chemical features could impair the proper formation of the receptorial complex, and/or has a destabilizing effect on the pre-assembled complex itself.
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Affiliation(s)
- Luigi Lembo-Fazio
- Dipartimento di Biologia e Biotecnologie "C. Darwin", Sapienza-Università di Roma, Rome, Italy
| | - Jean-Marc Billod
- Department of Structural and Chemical Biology, Centro de Investigaciones Biológicas, CIB-CSIC, Madrid, Spain
| | - Flaviana Di Lorenzo
- Dipartimento di Scienze Chimiche, Complesso Universitario Monte Sant'Angelo, Università di Napoli Federico II, Naples, Italy
| | - Ida Paciello
- Dipartimento di Biologia e Biotecnologie "C. Darwin", Sapienza-Università di Roma, Rome, Italy
| | - Mateusz Pallach
- Dipartimento di Scienze Chimiche, Complesso Universitario Monte Sant'Angelo, Università di Napoli Federico II, Naples, Italy
| | | | - Aurora Holgado
- Center for Inflammation Research, Unit of Molecular Signal Transduction in Inflammation, VIB, Ghent, Belgium.,Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Rudi Beyaert
- Center for Inflammation Research, Unit of Molecular Signal Transduction in Inflammation, VIB, Ghent, Belgium.,Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Manuel Fresno
- Diomune SL, Parque Científico de Madrid, Madrid, Spain
| | - Atsushi Shimoyama
- Department of Chemistry, Graduate School of Science, Osaka University, Osaka, Japan
| | - Rosa Lanzetta
- Dipartimento di Scienze Chimiche, Complesso Universitario Monte Sant'Angelo, Università di Napoli Federico II, Naples, Italy
| | - Koichi Fukase
- Department of Chemistry, Graduate School of Science, Osaka University, Osaka, Japan
| | - Djamel Gully
- IRD, Laboratoire des Symbioses Tropicales et Méditerranéennes (LSTM), UMR IRD/SupAgro/INRA/UM2/CIRAD, TA-A82/J - Campus de Baillarguet, Montpellier, France
| | - Eric Giraud
- IRD, Laboratoire des Symbioses Tropicales et Méditerranéennes (LSTM), UMR IRD/SupAgro/INRA/UM2/CIRAD, TA-A82/J - Campus de Baillarguet, Montpellier, France
| | - Sonsoles Martín-Santamaría
- Department of Structural and Chemical Biology, Centro de Investigaciones Biológicas, CIB-CSIC, Madrid, Spain
| | - Maria-Lina Bernardini
- Dipartimento di Biologia e Biotecnologie "C. Darwin", Sapienza-Università di Roma, Rome, Italy.,Istituto Pasteur Italia - Fondazione Cenci Bolognetti, Sapienza-Università di Roma, Rome, Italy
| | - Alba Silipo
- Dipartimento di Scienze Chimiche, Complesso Universitario Monte Sant'Angelo, Università di Napoli Federico II, Naples, Italy
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45
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Synthetic bottom-up approach reveals the complex interplay of Shigella effectors in regulation of epithelial cell death. Proc Natl Acad Sci U S A 2018; 115:6452-6457. [PMID: 29866849 DOI: 10.1073/pnas.1801310115] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Over the course of an infection, many Gram-negative bacterial pathogens use complex nanomachines to directly inject tens to hundreds of proteins (effectors) into the cytosol of infected host cells. These effectors rewire processes to promote bacterial replication and spread. The roles of effectors in pathogenesis have traditionally been investigated by screening for phenotypes associated with their absence, a top-down approach that can be limited, as effectors often act in a functionally redundant or additive manner. Here we describe a synthetic Escherichia coli-based bottom-up platform to conduct gain-of-function screens for roles of individual Shigella effectors in pathogenesis. As proof of concept, we screened for Shigella effectors that limit cell death induced on cytosolic entry of bacteria into epithelial cells. Using this platform, in addition to OspC3, an effector known to inhibit cell death via pyroptosis, we have identified OspD2 and IpaH1.4 as cell death inhibitors. In contrast to almost all type III effectors, OspD2 does not target a host cell process, but rather regulates the activity of the Shigella type III secretion apparatus limiting the cytosolic delivery (translocation) of effectors during an infection. Remarkably, by limiting the translocation of a single effector, VirA, OspD2 controls the timing of epithelial cell death via calpain-mediated necrosis. Together, these studies provide insight into the intricate manner by which Shigella effectors interact to establish a productive intracytoplasmic replication niche before the death of infected epithelial cells.
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46
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Belotserkovsky I, Sansonetti PJ. Shigella and Enteroinvasive Escherichia Coli. Curr Top Microbiol Immunol 2018; 416:1-26. [PMID: 30218158 DOI: 10.1007/82_2018_104] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Shigella and enteroinvasive Escherichia coli (EIEC) are gram-negative bacteria responsible for bacillary dysentery (shigellosis) in humans, which is characterized by invasion and inflammatory destruction of the human colonic epithelium. Different EIEC and Shigella subgroups rose independently from commensal E. coli through patho-adaptive evolution that included loss of functional genes interfering with the virulence and/or with the intracellular lifestyle of the bacteria, as well as acquisition of genetic elements harboring virulence genes. Among the latter is the large virulence plasmid encoding for a type three secretion system (T3SS), which enables translocation of virulence proteins (effectors) from the bacterium directly into the host cell cytoplasm. These effectors enable the pathogen to subvert epithelial cell functions, promoting its own uptake, replication in the host cytosol, and dissemination to adjacent cells while concomitantly inhibiting pro-inflammatory cell death. Furthermore, T3SS effectors are directly involved in Shigella manipulation of immune cells causing their dysfunction and promoting cell death. In the current chapter, we first describe the evolution of the enteroinvasive pathovars and then summarize the overall knowledge concerning the pathogenesis of these bacteria, with a particular focus on Shigella flexneri. Subversion of host cell functions in the human gut, both epithelial and immune cells, by different virulence factors is especially highlighted.
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Affiliation(s)
- Ilia Belotserkovsky
- Unité de Pathogénie Microbienne Moléculaire, Institut Pasteur, 28 Rue Du Dr Roux, 75724 Cedex 15, Paris, France.
| | - Philippe J Sansonetti
- Microbiologie et Maladies Infectieuses, Collège de France, 11 Place Marcelin Berthelot, 75005, Paris, France
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47
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Jurado-Sánchez B, Pacheco M, Rojo J, Escarpa A. Magnetocatalytic Graphene Quantum Dots Janus Micromotors for Bacterial Endotoxin Detection. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201701396] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Beatriz Jurado-Sánchez
- Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering; University of Alcalá; Madrid Spain
| | - Marta Pacheco
- Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering; University of Alcalá; Madrid Spain
| | - Jaime Rojo
- Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering; University of Alcalá; Madrid Spain
| | - Alberto Escarpa
- Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering; University of Alcalá; Madrid Spain
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48
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Jurado-Sánchez B, Pacheco M, Rojo J, Escarpa A. Magnetocatalytic Graphene Quantum Dots Janus Micromotors for Bacterial Endotoxin Detection. Angew Chem Int Ed Engl 2017; 56:6957-6961. [PMID: 28504463 DOI: 10.1002/anie.201701396] [Citation(s) in RCA: 134] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Indexed: 12/30/2022]
Abstract
Magnetocatalytic hybrid Janus micromotors encapsulating phenylboronic acid (PABA) modified graphene quantum dots (GQDs) are described herein as ultrafast sensors for the detection of deadly bacteria endotoxins. A bottom-up approach was adopted to synthesize an oil-in-water emulsion containing the GQDs along with a high loading of platinum and iron oxide nanoparticles on one side of the Janus micromotor body. The two different "active regions" enable highly efficient propulsion in the presence of hydrogen peroxide or magnetic actuation without the addition of a chemical fuel. Fluorescence quenching was observed upon the interaction of GQDs with the target endotoxin (LPS), whereby the PABA tags acted as highly specific recognition receptors of the LPS core polysaccharide region. Such adaptive hybrid operation and highly specific detection hold considerable promise for diverse clinical, agrofood, and biological applications and integration in future lab-on-chip technology.
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Affiliation(s)
- Beatriz Jurado-Sánchez
- Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcalá, Madrid, Spain
| | - Marta Pacheco
- Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcalá, Madrid, Spain
| | - Jaime Rojo
- Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcalá, Madrid, Spain
| | - Alberto Escarpa
- Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcalá, Madrid, Spain
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49
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Kieser KJ, Kagan JC. Multi-receptor detection of individual bacterial products by the innate immune system. Nat Rev Immunol 2017; 17:376-390. [PMID: 28461704 DOI: 10.1038/nri.2017.25] [Citation(s) in RCA: 116] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The receptors of the innate immune system detect specific microbial ligands to promote effective inflammatory and adaptive immune responses. Although this idea is well appreciated, studies in recent years have highlighted the complexity of innate immune detection, with multiple host receptors recognizing the same microbial ligand. Understanding the collective actions of diverse receptors that recognize common microbial signatures represents a new frontier in the study of innate immunity, and is the focus of this Review. Here, we discuss examples of individual bacterial cell wall components that are recognized by at least two and as many as four different receptors of the innate immune system. These receptors survey the extracellular or cytosolic spaces for their cognate ligands and operate in a complementary manner to induce distinct cellular responses. We further highlight that, despite this genetic diversity in receptors and pathways, common features exist to explain the operation of these receptors. These common features may help to provide unifying organizing principles associated with host defence.
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Affiliation(s)
- Karen J Kieser
- Department of Pediatrics, Harvard Medical School and Division of Gastroenterology, Boston Children's Hospital, Boston, Massachusetts 02115, USA
| | - Jonathan C Kagan
- Department of Pediatrics, Harvard Medical School and Division of Gastroenterology, Boston Children's Hospital, Boston, Massachusetts 02115, USA
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50
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Kramer CD, Genco CA. Microbiota, Immune Subversion, and Chronic Inflammation. Front Immunol 2017; 8:255. [PMID: 28348558 PMCID: PMC5346547 DOI: 10.3389/fimmu.2017.00255] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 02/21/2017] [Indexed: 12/12/2022] Open
Abstract
Several host-adapted pathogens and commensals have evolved mechanisms to evade the host innate immune system inducing a state of low-grade inflammation. Epidemiological studies have also documented the association of a subset of these microorganisms with chronic inflammatory disorders. In this review, we summarize recent studies demonstrating the role of the microbiota in chronic inflammatory diseases and discuss how specific microorganisms subvert or inhibit protective signaling normally induced by toll-like receptors (TLRs). We highlight our work on the oral pathogen Porphyromonas gingivalis and discuss the role of microbial modulation of lipid A structures in evasion of TLR4 signaling and resulting systemic immunopathology associated with atherosclerosis. P. gingivalis intrinsically expresses underacylated lipid A moieties and can modify the phosphorylation of lipid A, leading to altered TLR4 signaling. Using P. gingivalis mutant strains expressing distinct lipid A moieties, we demonstrated that expression of antagonist lipid A was associated with P. gingivalis-mediated systemic inflammation and immunopathology, whereas strains expressing agonist lipid A exhibited modest systemic inflammation. Likewise, mice deficient in TLR4 were more susceptible to vascular inflammation after oral infection with P. gingivalis wild-type strain compared to mice possessing functional TLR4. Collectively, our studies support a role for P. gingivalis-mediated dysregulation of innate and adaptive responses resulting in immunopathology and systemic inflammation. We propose that anti-TLR4 interventions must be designed with caution, given the balance between the protective and destructive roles of TLR signaling in response to microbiota and associated immunopathologies.
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Affiliation(s)
- Carolyn D Kramer
- Department of Integrative Physiology and Pathobiology, Tufts University School of Medicine , Boston, MA , USA
| | - Caroline Attardo Genco
- Department of Integrative Physiology and Pathobiology, Tufts University School of Medicine , Boston, MA , USA
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