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Challagundla N, Phadnis D, Gupta A, Agrawal-Rajput R. Host Lipid Manipulation by Intracellular Bacteria: Moonlighting for Immune Evasion. J Membr Biol 2023; 256:393-411. [PMID: 37938349 DOI: 10.1007/s00232-023-00296-8] [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: 09/11/2023] [Accepted: 10/11/2023] [Indexed: 11/09/2023]
Abstract
Lipids are complex organic molecules that fulfill energy demands and sometimes act as signaling molecules. They are mostly found in membranes, thus playing an important role in membrane trafficking and protecting the cell from external dangers. Based on the composition of the lipids, their fluidity and charge, their interaction with embedded proteins vary greatly. Bacteria can hijack host lipids to satisfy their energy needs or to conceal themselves from host cells. Intracellular bacteria continuously exploit host, from their entry into host cells utilizing host lipid machinery to exiting through the cells. This acquisition of lipids from host cells helps in their disguise mechanism. The current review explores various mechanisms employed by the intracellular bacteria to manipulate and acquire host lipids. It discusses their role in manipulating host membranes and the subsequence impact on the host cells. Modulating these lipids in macrophages not only serve the purpose of the pathogen but also modulates the macrophage energy metabolism and functional state. Additionally, we have explored the intricate pathogenic relationship and the potential prospects of using this knowledge in lipid-based therapeutics to disrupt pathogen dominance.
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Affiliation(s)
- Naveen Challagundla
- Immunology Lab, Indian Institute of Advanced Research, Koba Institutional Area, Gandhinagar, Gujarat, 382426, India
| | - Deepti Phadnis
- Immunology Lab, Indian Institute of Advanced Research, Koba Institutional Area, Gandhinagar, Gujarat, 382426, India
| | - Aakriti Gupta
- Immunology Lab, Indian Institute of Advanced Research, Koba Institutional Area, Gandhinagar, Gujarat, 382426, India
| | - Reena Agrawal-Rajput
- Immunology Lab, Indian Institute of Advanced Research, Koba Institutional Area, Gandhinagar, Gujarat, 382426, India.
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2
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Kaisanlahti A, Salmi S, Kumpula S, Amatya SB, Turunen J, Tejesvi M, Byts N, Tapiainen T, Reunanen J. Bacterial extracellular vesicles - brain invaders? A systematic review. Front Mol Neurosci 2023; 16:1227655. [PMID: 37781094 PMCID: PMC10537964 DOI: 10.3389/fnmol.2023.1227655] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 08/28/2023] [Indexed: 10/03/2023] Open
Abstract
Introduction Knowledge on the human gut microbiota in health and disease continues to rapidly expand. In recent years, changes in the gut microbiota composition have been reported as a part of the pathology in numerous neurodegenerative diseases. Bacterial extracellular vesicles (EVs) have been suggested as a novel mechanism for the crosstalk between the brain and gut microbiota, physiologically connecting the observed changes in the brain to gut microbiota dysbiosis. Methods Publications reporting findings on bacterial EVs passage through the blood-brain barrier were identified in PubMed and Scopus databases. Results The literature search yielded 138 non-duplicate publications, from which 113 records were excluded in title and abstract screening step. From 25 publications subjected to full-text screening, 8 were excluded. The resulting 17 publications were considered for the review. Discussion Bacterial EVs have been described with capability to cross the blood-brain barrier, but the mechanisms behind the crossing remain largely unknown. Importantly, very little data exists in this context on EVs secreted by the human gut microbiota. This systematic review summarizes the present evidence of bacterial EVs crossing the blood-brain barrier and highlights the importance of future research on gut microbiota-derived EVs in the context of gut-brain communication across the blood-brain barrier.
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Affiliation(s)
- Anna Kaisanlahti
- Biocenter Oulu, University of Oulu, Oulu, Finland
- Research Unit of Translational Medicine, University of Oulu, Oulu, Finland
| | - Sonja Salmi
- Disease Networks Research Unit, Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Sohvi Kumpula
- Biocenter Oulu, University of Oulu, Oulu, Finland
- Research Unit of Translational Medicine, University of Oulu, Oulu, Finland
| | - Sajeen Bahadur Amatya
- Biocenter Oulu, University of Oulu, Oulu, Finland
- Research Unit of Translational Medicine, University of Oulu, Oulu, Finland
| | - Jenni Turunen
- Biocenter Oulu, University of Oulu, Oulu, Finland
- Research Unit of Clinical Medicine, University of Oulu, Oulu, Finland
| | - Mysore Tejesvi
- Biocenter Oulu, University of Oulu, Oulu, Finland
- Department of Ecology and Genetics, Faculty of Science, University of Oulu, Oulu, Finland
| | - Nadiya Byts
- Biocenter Oulu, University of Oulu, Oulu, Finland
- Research Unit of Translational Medicine, University of Oulu, Oulu, Finland
| | - Terhi Tapiainen
- Biocenter Oulu, University of Oulu, Oulu, Finland
- Research Unit of Clinical Medicine, University of Oulu, Oulu, Finland
- Department of Pediatrics and Adolescent Medicine, Oulu University Hospital, Oulu, Finland
| | - Justus Reunanen
- Biocenter Oulu, University of Oulu, Oulu, Finland
- Research Unit of Translational Medicine, University of Oulu, Oulu, Finland
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3
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Chatterjee R, Chowdhury AR, Mukherjee D, Chakravortty D. Lipid larceny: channelizing host lipids for establishing successful pathogenesis by bacteria. Virulence 2021; 12:195-216. [PMID: 33356849 PMCID: PMC7808437 DOI: 10.1080/21505594.2020.1869441] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 12/03/2020] [Accepted: 12/17/2020] [Indexed: 12/16/2022] Open
Abstract
Lipids are complex organic compounds made up of carbon, oxygen, and hydrogen. These play a diverse and intricate role in cellular processes like membrane trafficking, protein sorting, signal transduction, and bacterial infections. Both Gram-positive bacteria (Staphylococcus sp., Listeria monocytogenes, etc.) and Gram-negative bacteria (Chlamydia sp., Salmonella sp., E. coli, etc.) can hijack the various host-lipids and utilize them structurally as well as functionally to mount a successful infection. The pathogens can deploy with various arsenals to exploit host membrane lipids and lipid-associated receptors as an attachment for toxins' landing or facilitate their entry into the host cellular niche. Bacterial species like Mycobacterium sp. can also modulate the host lipid metabolism to fetch its carbon source from the host. The sequential conversion of host membrane lipids into arachidonic acid and prostaglandin E2 due to increased activity of cPLA-2 and COX-2 upon bacterial infection creates immunosuppressive conditions and facilitates the intracellular growth and proliferation of bacteria. However, lipids' more debatable role is that they can also be a blessing in disguise. Certain host-lipids, especially sphingolipids, have been shown to play a crucial antibacterial role and help the host in combating the infections. This review shed light on the detailed role of host lipids in bacterial infections and the current understanding of the lipid in therapeutics. We have also discussed potential prospects and the need of the hour to help us cope in this race against deadly pathogens and their rapidly evolving stealthy virulence strategies.
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Affiliation(s)
- Ritika Chatterjee
- Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, India
| | - Atish Roy Chowdhury
- Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, India
| | - Debapriya Mukherjee
- Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, India
| | - Dipshikha Chakravortty
- Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, India
- Centre for Biosystems Science and Engineering, Indian Institute of Science, Bangalore, India
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4
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De Gaetano GV, Lentini G, Galbo R, Coppolino F, Famà A, Teti G, Beninati C. Invasion and trafficking of hypervirulent group B streptococci in polarized enterocytes. PLoS One 2021; 16:e0253242. [PMID: 34129624 PMCID: PMC8205152 DOI: 10.1371/journal.pone.0253242] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 06/01/2021] [Indexed: 11/29/2022] Open
Abstract
Streptococcus agalactiae (group B streptococcus or GBS) is a commensal bacterium that can frequently behave as a pathogen, particularly in the neonatal period and in the elderly. The gut is a primary site of GBS colonization and a potential port of entry during neonatal infections caused by hypervirulent clonal complex 17 (CC17) strains. Here we studied the interactions between the prototypical CC17 BM110 strain and polarized enterocytes using the Caco-2 cell line. GBS could adhere to and invade these cells through their apical or basolateral surfaces. Basolateral invasion was considerably more efficient than apical invasion and predominated under conditions resulting in weakening of cell-to-cell junctions. Bacterial internalization occurred by a mechanism involving caveolae- and lipid raft-dependent endocytosis and actin re-organization, but not clathrin-dependent endocytosis. In the first steps of Caco-2 invasion, GBS colocalized with the early endocytic marker EEA-1, to later reside in acidic vacuoles. Taken together, these data suggest that CC17 GBS selectively adheres to the lateral surface of enterocytes from which it enters through caveolar lipid rafts using a classical, actin-dependent endocytic pathway. These data may be useful to develop alternative preventive strategies aimed at blocking GBS invasion of the intestinal barrier.
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Affiliation(s)
| | - Germana Lentini
- Department of Human Pathology, University of Messina, Messina, Italy
| | - Roberta Galbo
- Department of Chemical, Biological and Pharmaceutical Sciences, University of Messina, Messina, Italy
| | | | - Agata Famà
- Department of Human Pathology, University of Messina, Messina, Italy
| | | | - Concetta Beninati
- Department of Human Pathology, University of Messina, Messina, Italy
- Scylla Biotech Srl, Messina, Italy
- * E-mail:
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5
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Outer Membrane Lipid Secretion and the Innate Immune Response to Gram-Negative Bacteria. Infect Immun 2020; 88:IAI.00920-19. [PMID: 32253250 DOI: 10.1128/iai.00920-19] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The outer membrane (OM) of Gram-negative bacteria is an asymmetric lipid bilayer that consists of inner leaflet phospholipids and outer leaflet lipopolysaccharides (LPS). The asymmetric character and unique biochemistry of LPS molecules contribute to the OM's ability to function as a molecular permeability barrier that protects the bacterium against hazards in the environment. Assembly and regulation of the OM have been extensively studied for understanding mechanisms of antibiotic resistance and bacterial defense against host immunity; however, there is little knowledge on how Gram-negative bacteria release their OMs into their environment to manipulate their hosts. Discoveries in bacterial lipid trafficking, OM lipid homeostasis, and host recognition of microbial patterns have shed new light on how microbes secrete OM vesicles (OMVs) to influence inflammation, cell death, and disease pathogenesis. Pathogens release OMVs that contain phospholipids, like cardiolipins, and components of LPS molecules, like lipid A endotoxins. These multiacylated lipid amphiphiles are molecular patterns that are differentially detected by host receptors like the Toll-like receptor 4/myeloid differentiation factor 2 complex (TLR4/MD-2), mouse caspase-11, and human caspases 4 and 5. We discuss how lipid ligands on OMVs engage these pattern recognition receptors on the membranes and in the cytosol of mammalian cells. We then detail how bacteria regulate OM lipid asymmetry, negative membrane curvature, and the phospholipid-to-LPS ratio to control OMV formation. The goal is to highlight intersections between OM lipid regulation and host immunity and to provide working models for how bacterial lipids influence vesicle formation.
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6
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Bukrinsky MI, Mukhamedova N, Sviridov D. Lipid rafts and pathogens: the art of deception and exploitation. J Lipid Res 2020; 61:601-610. [PMID: 31615838 PMCID: PMC7193957 DOI: 10.1194/jlr.tr119000391] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 10/07/2019] [Indexed: 02/06/2023] Open
Abstract
Lipid rafts, solid regions of the plasma membrane enriched in cholesterol and glycosphingolipids, are essential parts of a cell. Functionally, lipid rafts present a platform that facilitates interaction of cells with the outside world. However, the unique properties of lipid rafts required to fulfill this function at the same time make them susceptible to exploitation by pathogens. Many steps of pathogen interaction with host cells, and sometimes all steps within the entire lifecycle of various pathogens, rely on host lipid rafts. Such steps as binding of pathogens to the host cells, invasion of intracellular parasites into the cell, the intracellular dwelling of parasites, microbial assembly and exit from the host cell, and microbe transfer from one cell to another all involve lipid rafts. Interaction also includes modification of lipid rafts in host cells, inflicted by pathogens from both inside and outside the cell, through contact or remotely, to advance pathogen replication, to utilize cellular resources, and/or to mitigate immune response. Here, we provide a systematic overview of how and why pathogens interact with and exploit host lipid rafts, as well as the consequences of this interaction for the host, locally and systemically, and for the microbe. We also raise the possibility of modulation of lipid rafts as a therapeutic approach against a variety of infectious agents.
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Affiliation(s)
- Michael I Bukrinsky
- Department of Microbiology, Immunology, and Tropical Medicine,George Washington University School of Medicine and Health Science, Washington, DC 20037
| | | | - Dmitri Sviridov
- Baker Heart and Diabetes Institute, Melbourne 3004, Australia. mailto:
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7
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Caruana JC, Walper SA. Bacterial Membrane Vesicles as Mediators of Microbe - Microbe and Microbe - Host Community Interactions. Front Microbiol 2020; 11:432. [PMID: 32265873 PMCID: PMC7105600 DOI: 10.3389/fmicb.2020.00432] [Citation(s) in RCA: 147] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 03/02/2020] [Indexed: 01/18/2023] Open
Abstract
Bacterial membrane vesicles are proteoliposomal nanoparticles produced by both Gram-negative and Gram-positive bacteria. As they originate from the outer surface of the bacteria, their composition and content is generally similar to the parent bacterium’s membrane and cytoplasm. However, there is ample evidence that preferential packaging of proteins, metabolites, and toxins into vesicles does occur. Incorporation into vesicles imparts a number of benefits to the cargo, including protection from degradation by other bacteria, the host organism, or environmental factors, maintenance of a favorable microenvironment for enzymatic activity, and increased potential for long-distance movement. This enables vesicles to serve specialized functions tailored to changing or challenging environments, particularly in regard to microbial community interactions including quorum sensing, biofilm formation, antibiotic resistance, antimicrobial peptide expression and deployment, and nutrient acquisition. Additionally, based on their contents, vesicles play crucial roles in host-microbe interactions as carriers of virulence factors and other modulators of host cell function. Here, we discuss recent advances in our understanding of how vesicles function as signals both within microbial communities and between pathogenic or commensal microbes and their mammalian hosts. We also highlight a few areas that are currently ripe for additional research, including the mechanisms of selective cargo packaging into membrane vesicles and of cargo processing once it enters mammalian host cells, the function of vesicles in transfer of nucleic acids among bacteria, and the possibility of engineering commensal bacteria to deliver cargo of interest to mammalian hosts in a controlled manner.
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Affiliation(s)
- Julie C Caruana
- American Society for Engineering Education, Washington, DC, United States
| | - Scott A Walper
- US Naval Research Laboratory, Center for Biomolecular Science and Engineering, Washington, DC, United States
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8
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Gitsels A, Sanders N, Vanrompay D. Chlamydial Infection From Outside to Inside. Front Microbiol 2019; 10:2329. [PMID: 31649655 PMCID: PMC6795091 DOI: 10.3389/fmicb.2019.02329] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 09/24/2019] [Indexed: 12/16/2022] Open
Abstract
Chlamydia are obligate intracellular bacteria, characterized by a unique biphasic developmental cycle. Specific interactions with the host cell are crucial for the bacteria’s survival and amplification because of the reduced chlamydial genome. At the start of infection, pathogen-host interactions are set in place in order for Chlamydia to enter the host cell and reach the nutrient-rich peri-Golgi region. Once intracellular localization is established, interactions with organelles and pathways of the host cell enable the necessary hijacking of host-derived nutrients. Detailed information on the aforementioned processes will increase our understanding on the intracellular pathogenesis of chlamydiae and hence might lead to new strategies to battle chlamydial infection. This review summarizes how chlamydiae generate their intracellular niche in the host cell, acquire host-derived nutrients in order to enable their growth and finally exit the host cell in order to infect new cells. Moreover, the evolution in the development of molecular genetic tools, necessary for studying the chlamydial infection biology in more depth, is discussed in great detail.
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Affiliation(s)
- Arlieke Gitsels
- Laboratory for Immunology and Animal Biotechnology, Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Niek Sanders
- Laboratory of Gene Therapy, Department of Nutrition, Genetics and Ethology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Daisy Vanrompay
- Laboratory for Immunology and Animal Biotechnology, Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
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9
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Fernández-Oliva A, Ortega-González P, Risco C. Targeting host lipid flows: Exploring new antiviral and antibiotic strategies. Cell Microbiol 2019; 21:e12996. [PMID: 30585688 PMCID: PMC7162424 DOI: 10.1111/cmi.12996] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 12/04/2018] [Accepted: 12/17/2018] [Indexed: 12/28/2022]
Abstract
Bacteria and viruses pose serious challenges for humans because they evolve continuously. Despite ongoing efforts, antiviral drugs to treat many of the most troubling viruses have not been approved yet. The recent launch of new antimicrobials is generating hope as more and more pathogens around the world become resistant to available drugs. But extra effort is still needed. One of the current strategies for antiviral and antibiotic drug development is the search for host cellular pathways used by many different pathogens. For example, many viruses and bacteria alter lipid synthesis and transport to build their own organelles inside infected cells. The characterization of these interactions will be fundamental to identify new targets for antiviral and antibiotic drug development. This review discusses how viruses and bacteria subvert cell machineries for lipid synthesis and transport and summarises the most promising compounds that interfere with these pathways.
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Affiliation(s)
| | | | - Cristina Risco
- Cell Structure Lab, National Centre for Biotechnology, CNB-CSIC, Madrid, Spain
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10
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Lausen M, Christiansen G, Bouet Guldbæk Poulsen T, Birkelund S. Immunobiology of monocytes and macrophages during Chlamydia trachomatis infection. Microbes Infect 2018; 21:73-84. [PMID: 30528899 DOI: 10.1016/j.micinf.2018.10.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 10/11/2018] [Accepted: 10/11/2018] [Indexed: 02/03/2023]
Abstract
Infections caused by the intracellular bacterium Chlamydia trachomatis are a global health burden affecting more than 100 million people annually causing damaging long-lasting infections. In this review, we will present and discuss important aspects of the interaction between C. trachomatis and monocytes/macrophages.
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Affiliation(s)
- Mads Lausen
- Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 3b, 9220 Aalborg Ø, Denmark.
| | - Gunna Christiansen
- Department of Biomedicine, Aarhus University, Wilhelms Meyers Allé 4, 8000 Aarhus, Denmark
| | | | - Svend Birkelund
- Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 3b, 9220 Aalborg Ø, Denmark
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11
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Verma R, Sahu R, Dixit S, Duncan SA, Giambartolomei GH, Singh SR, Dennis VA. The Chlamydia M278 Major Outer Membrane Peptide Encapsulated in the Poly(lactic acid)-Poly(ethylene glycol) Nanoparticulate Self-Adjuvanting Delivery System Protects Mice Against a Chlamydia muridarum Genital Tract Challenge by Stimulating Robust Systemic and Local Mucosal Immune Responses. Front Immunol 2018; 9:2369. [PMID: 30374357 PMCID: PMC6196261 DOI: 10.3389/fimmu.2018.02369] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 09/24/2018] [Indexed: 12/26/2022] Open
Abstract
Recently, we reported that our PPM chlamydial nanovaccine [a biodegradable co-polymeric PLA-PEG (poly(lactic acid)-poly(ethylene glycol))-encapsulated M278 peptide (derived from the major outer membrane protein (MOMP) of Chlamydia)] exploits the caveolin-mediated endocytosis pathway for endosomal processing and MHC class II presentation to immune-potentiate Chlamydia-specific CD4+ T-cell immune effector responses. In the present study, we employed the Chlamydia muridarum mouse infection model to evaluate the protective efficacy of PPM against a genital tract challenge. Our results show that mice immunized with PPM were significantly protected against a homologous genital tract challenge evidently by reduced vaginal bacterial loads. Protection of mice correlated with enhanced Chlamydia-specific adaptive immune responses predominated by IFN-γ along with CD4+ T-cells proliferation and their differentiation to CD4+ memory (CD44high CD62Lhigh) and effector (CD44high CD62Llow) T-cell phenotypes. We observed the elevation of M278- and MOMP-specific serum antibodies with high avidity in the ascending order IgG1 > IgG2b > IgG2a. A key finding was the elevated mucosal IgG1 and IgA antibody titers followed by an increase in MOMP-specific IgA after the challenge. The Th1/Th2 antibody titer ratios (IgG2a/IgG1 and IgG2b/IgG1) revealed that PPM evoked a Th2-directed response, which skewed to a Th1-dominated antibody response after the bacterial challenge of mice. In addition, PPM immune sera neutralized the infectivity of C. muridarum in McCoy cells, suggesting the triggering of functional neutralizing antibodies. Herein, we reveal for the first time that subcutaneous immunization with the self-adjuvanting biodegradable co-polymeric PPM nanovaccine immune-potentiated robust CD4+ T cell-mediated immune effector responses; a mixed Th1 and Th2 antibody response and local mucosal IgA to protect mice against a chlamydial genital tract challenge.
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Affiliation(s)
- Richa Verma
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, United States
| | - Rajnish Sahu
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, United States
| | - Saurabh Dixit
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, United States
| | - Skyla A Duncan
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, United States
| | - Guillermo H Giambartolomei
- Instituto de Inmunología, Genética y Metabolismo (INIGEM), CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Shree R Singh
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, United States
| | - Vida A Dennis
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, United States
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12
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Lausen M, Christiansen G, Karred N, Winther R, Poulsen TBG, Palarasah Y, Birkelund S. Complement C3 opsonization of Chlamydia trachomatis facilitates uptake in human monocytes. Microbes Infect 2018; 20:328-336. [PMID: 29729435 DOI: 10.1016/j.micinf.2018.04.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2017] [Revised: 03/13/2018] [Accepted: 04/23/2018] [Indexed: 01/08/2023]
Abstract
Chlamydia trachomatis is an obligate intracellular bacterium that causes severe infections, which can lead to infertility and ectopic pregnancy. Although both innate and adaptive immune responses are elicited during chlamydial infection the bacterium succeeds to evade host defense mechanisms establishing chronic infections. Thus, studying the host-pathogen interaction during chlamydial infection is of importance to understand how C. trachomatis can cause chronic infections. Both the complement system and monocytes play essential roles in anti-bacterial defense, and, therefore, we investigated the interaction between the complement system and the human pathogens C. trachomatis D and L2. Complement competent serum facilitated rapid uptake of both chlamydial serovars into monocytes. Using immunoelectron microscopy, we showed that products of complement C3 were loosely deposited on the bacterial surface in complement competent serum and further characterization demonstrated that the deposited C3 product was the opsonin iC3b. Using C3-depleted serum we confirmed that complement C3 facilitates rapid uptake of chlamydiae into monocytes in complement competent serum. Complement facilitated uptake did not influence intracellular survival of C. trachomatis or C. trachomatis-induced cytokine secretion. Hence, C. trachomatis D and L2 activate the complement system leading to chlamydial opsonization by iC3b and subsequent phagocytosis, activation and bacterial elimination by human monocytes.
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Affiliation(s)
- Mads Lausen
- Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 3b, 9220, Aalborg Ø, Denmark
| | - Gunna Christiansen
- Department of Biomedicine, Aarhus University, Wilhelms Meyers Allé 4, 8000, Aarhus, Denmark
| | - Nichlas Karred
- Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 3b, 9220, Aalborg Ø, Denmark
| | - Robert Winther
- Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 3b, 9220, Aalborg Ø, Denmark
| | - Thomas Bouet Guldbæk Poulsen
- Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 3b, 9220, Aalborg Ø, Denmark
| | - Yaseelan Palarasah
- Unit for Thrombosis Research, Institute of Public Health, University of Southern Denmark, Esbjerg, Denmark
| | - Svend Birkelund
- Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 3b, 9220, Aalborg Ø, Denmark.
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13
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Dixit S, Sahu R, Verma R, Duncan S, Giambartolomei GH, Singh SR, Dennis VA. Caveolin-mediated endocytosis of the Chlamydia M278 outer membrane peptide encapsulated in poly(lactic acid)-Poly(ethylene glycol) nanoparticles by mouse primary dendritic cells enhances specific immune effectors mediated by MHC class II and CD4 + T cells. Biomaterials 2018; 159:130-145. [PMID: 29324305 PMCID: PMC5801148 DOI: 10.1016/j.biomaterials.2017.12.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2017] [Revised: 12/14/2017] [Accepted: 12/22/2017] [Indexed: 12/18/2022]
Abstract
We previously developed a Chlamydia trachomatis nanovaccine (PPM) by encapsulating a chlamydial M278 peptide within poly(lactic acid)-poly(ethylene glycol) biodegradable nanoparticles that immunopotentiated Chlamydia-specific immune effector responses in mice. Herein, we investigated the mechanistic interactions of PPM with mouse bone marrow-derived dendritic cells (DCs) for its uptake, trafficking, and T cell activation. Our results reveal that PPM triggered enhanced expression of effector cytokines and chemokines, surface activation markers (Cd1d2, Fcgr1), pathogen-sensing receptors (TLR2, Nod1), co-stimulatory (CD40, CD80, CD86) and MHC class I and II molecules. Co-culturing of PPM-primed DCs with T cells from C. muridarum vaccinated mice yielded an increase in Chlamydia-specific immune effector responses including CD3+ lymphoproliferation, CD3+CD4+ IFN-γ-secreting cells along with CD3+CD4+ memory (CD44high and CD62Lhigh) and effector (CD44high and CD62Llow) phenotypes. Intracellular trafficking analyses revealed an intense expression and colocalization of PPM predominantly in endosomes. PPM also upregulated the transcriptional and protein expression of the endocytic mediator, caveolin-1 in DCs. More importantly, the specific inhibition of caveolin-1 led to decreased expression of PPM-induced cytokines and co-stimulatory molecules. Our investigation shows that PPM provided enhancement of uptake, probably by exploiting the caveolin-mediated endocytosis pathway, endosomal processing, and MHC II presentation to immunopotentiate Chlamydia-specific immune effector responses mediated by CD4+ T cells.
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Affiliation(s)
- Saurabh Dixit
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL 36104, USA
| | - Rajnish Sahu
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL 36104, USA
| | - Richa Verma
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL 36104, USA
| | - Skyla Duncan
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL 36104, USA
| | - Guillermo H Giambartolomei
- Instituto de Inmunología, Genética y Metabolismo (INIGEM), CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Shree R Singh
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL 36104, USA
| | - Vida A Dennis
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL 36104, USA.
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14
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Bagam P, Singh DP, Inda ME, Batra S. Unraveling the role of membrane microdomains during microbial infections. Cell Biol Toxicol 2017; 33:429-455. [PMID: 28275881 PMCID: PMC7088210 DOI: 10.1007/s10565-017-9386-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 02/06/2017] [Indexed: 01/06/2023]
Abstract
Infectious diseases pose major socioeconomic and health-related threats to millions of people across the globe. Strategies to combat infectious diseases derive from our understanding of the complex interactions between the host and specific bacterial, viral, and fungal pathogens. Lipid rafts are membrane microdomains that play important role in life cycle of microbes. Interaction of microbial pathogens with host membrane rafts influences not only their initial colonization but also their spread and the induction of inflammation. Therefore, intervention strategies aimed at modulating the assembly of membrane rafts and/or regulating raft-directed signaling pathways are attractive approaches for the. management of infectious diseases. The current review discusses the latest advances in terms of techniques used to study the role of membrane microdomains in various pathological conditions and provides updated information regarding the role of membrane rafts during bacterial, viral and fungal infections.
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Affiliation(s)
- Prathyusha Bagam
- Laboratory of Pulmonary Immuno-Toxicology, Department of Environmental Toxicology, Health Research Center, Southern University and A&M College, Baton Rouge, LA, 70813, USA
| | - Dhirendra P Singh
- Laboratory of Pulmonary Immuno-Toxicology, Department of Environmental Toxicology, Health Research Center, Southern University and A&M College, Baton Rouge, LA, 70813, USA
| | - Maria Eugenia Inda
- Departamento de Microbiología, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Suipacha, Rosario, Argentina
| | - Sanjay Batra
- Laboratory of Pulmonary Immuno-Toxicology, Department of Environmental Toxicology, Health Research Center, Southern University and A&M College, Baton Rouge, LA, 70813, USA.
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15
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Koch-Edelmann S, Banhart S, Saied EM, Rose L, Aeberhard L, Laue M, Doellinger J, Arenz C, Heuer D. The cellular ceramide transport protein CERT promotes Chlamydia psittaci infection and controls bacterial sphingolipid uptake. Cell Microbiol 2017; 19. [PMID: 28544656 DOI: 10.1111/cmi.12752] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 05/15/2017] [Accepted: 05/15/2017] [Indexed: 01/04/2023]
Abstract
Chlamydiaceae are bacterial pathogens that cause diverse diseases in humans and animals. Despite their broad host and tissue tropism, all Chlamydia species share an obligate intracellular cycle of development and have evolved sophisticated mechanisms to interact with their eukaryotic host cells. Here, we have analysed interactions of the zoonotic pathogen Chlamydia psittaci with a human epithelial cell line. We found that C. psittaci recruits the ceramide transport protein (CERT) to its inclusion. Chemical inhibition and CRISPR/Cas9-mediated knockout of CERT showed that CERT is a crucial factor for C. psittaci infections thereby affecting different stages of the infection including inclusion growth and infectious progeny formation. Interestingly, the uptake of fluorescently labelled sphingolipids in bacteria inside the inclusion was accelerated in CERT-knockout cells indicating that C. psittaci can exploit CERT-independent sphingolipid uptake pathways. Moreover, the CERT-specific inhibitor HPA-12 strongly diminished sphingolipid transport to inclusions of infected CERT-knockout cells, suggesting that other HPA-12-sensitive factors are involved in sphingolipid trafficking to C. psittaci. Further analysis is required to decipher these interactions and to understand their contributions to bacterial development, host range, tissue tropism, and disease outcome.
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Affiliation(s)
- Sophia Koch-Edelmann
- Junior Research Group "Sexually Transmitted Bacterial Pathogens" (NG 5), Robert Koch Institute, Berlin, Germany
| | - Sebastian Banhart
- Junior Research Group "Sexually Transmitted Bacterial Pathogens" (NG 5), Robert Koch Institute, Berlin, Germany
| | - Essa M Saied
- Organic and Bioorganic Chemistry, Department of Chemistry, Humboldt-Universität zu Berlin, Berlin, Germany.,Chemistry Department, Faculty of Science, Suez Canal University, Ismailia, Egypt
| | - Laura Rose
- Junior Research Group "Sexually Transmitted Bacterial Pathogens" (NG 5), Robert Koch Institute, Berlin, Germany
| | - Lukas Aeberhard
- Junior Research Group "Sexually Transmitted Bacterial Pathogens" (NG 5), Robert Koch Institute, Berlin, Germany
| | - Michael Laue
- Advanced Light and Electron Microscopy (ZBS 4), Robert Koch Institute, Berlin, Germany
| | - Joerg Doellinger
- Proteomics and Spectroscopy (ZBS 6), Robert Koch Institute, Berlin, Germany
| | - Christoph Arenz
- Organic and Bioorganic Chemistry, Department of Chemistry, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Dagmar Heuer
- Junior Research Group "Sexually Transmitted Bacterial Pathogens" (NG 5), Robert Koch Institute, Berlin, Germany
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16
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Samanta D, Mulye M, Clemente TM, Justis AV, Gilk SD. Manipulation of Host Cholesterol by Obligate Intracellular Bacteria. Front Cell Infect Microbiol 2017; 7:165. [PMID: 28529926 PMCID: PMC5418226 DOI: 10.3389/fcimb.2017.00165] [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: 01/06/2017] [Accepted: 04/18/2017] [Indexed: 12/29/2022] Open
Abstract
Cholesterol is a multifunctional lipid that plays important metabolic and structural roles in the eukaryotic cell. Despite having diverse lifestyles, the obligate intracellular bacterial pathogens Chlamydia, Coxiella, Anaplasma, Ehrlichia, and Rickettsia all target cholesterol during host cell colonization as a potential source of membrane, as well as a means to manipulate host cell signaling and trafficking. To promote host cell entry, these pathogens utilize cholesterol-rich microdomains known as lipid rafts, which serve as organizational and functional platforms for host signaling pathways involved in phagocytosis. Once a pathogen gains entrance to the intracellular space, it can manipulate host cholesterol trafficking pathways to access nutrient-rich vesicles or acquire membrane components for the bacteria or bacteria-containing vacuole. To acquire cholesterol, these pathogens specifically target host cholesterol metabolism, uptake, efflux, and storage. In this review, we examine the strategies obligate intracellular bacterial pathogens employ to manipulate cholesterol during host cell colonization. Understanding how obligate intracellular pathogens target and use host cholesterol provides critical insight into the host-pathogen relationship.
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Affiliation(s)
- Dhritiman Samanta
- Department of Microbiology and Immunology, Indiana University School of MedicineIndianapolis, IN, USA
| | - Minal Mulye
- Department of Microbiology and Immunology, Indiana University School of MedicineIndianapolis, IN, USA
| | - Tatiana M Clemente
- Department of Microbiology and Immunology, Indiana University School of MedicineIndianapolis, IN, USA
| | - Anna V Justis
- Department of Microbiology and Immunology, Indiana University School of MedicineIndianapolis, IN, USA
| | - Stacey D Gilk
- Department of Microbiology and Immunology, Indiana University School of MedicineIndianapolis, IN, USA
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17
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Gabor KA, Fessler MB. Roles of the Mevalonate Pathway and Cholesterol Trafficking in Pulmonary Host Defense. Curr Mol Pharmacol 2017; 10:27-45. [PMID: 26758950 PMCID: PMC6026538 DOI: 10.2174/1874467209666160112123603] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 08/01/2015] [Accepted: 12/23/2015] [Indexed: 01/17/2023]
Abstract
The mevalonic acid synthesis pathway, cholesterol, and lipoproteins play fundamental roles in lung physiology and the innate immune response. Recent literature investigating roles for cholesterol synthesis and trafficking in host defense against respiratory infection was critically reviewed. The innate immune response and the cholesterol biosynthesis/trafficking network regulate one another, with important implications for pathogen invasion and host defense in the lung. The activation of pathogen recognition receptors and downstream cellular host defense functions are critically sensitive to cellular cholesterol. Conversely, microorganisms can co-opt the sterol/lipoprotein network in order to facilitate replication and evade immunity. Emerging literature suggests the potential for harnessing these insights towards therapeutic development. Given that >50% of adults in the U.S. have serum cholesterol abnormalities and pneumonia remains a leading cause of death, the potential impact of cholesterol on pulmonary host defense is of tremendous public health significance and warrants further mechanistic and translational investigation.
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Affiliation(s)
| | - Michael B Fessler
- Immunity, Inflammation, and Disease Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T.W. Alexander Drive, P.O. Box 12233, Maildrop D2-01, Research Triangle Park, NC 27709, United States
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18
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O'Donoghue EJ, Krachler AM. Mechanisms of outer membrane vesicle entry into host cells. Cell Microbiol 2016; 18:1508-1517. [PMID: 27529760 PMCID: PMC5091637 DOI: 10.1111/cmi.12655] [Citation(s) in RCA: 203] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 08/05/2016] [Accepted: 08/12/2016] [Indexed: 01/18/2023]
Abstract
Bacterial outer membrane vesicles (OMVs) are nano‐sized compartments consisting of a lipid bilayer that encapsulates periplasm‐derived, luminal content. OMVs, which pinch off of Gram‐negative bacteria, are now recognized as a generalized secretion pathway which provides a means to transfer cargo to other bacterial cells as well as eukaryotic cells. Compared with other secretion systems, OMVs can transfer a chemically extremely diverse range of cargo, including small molecules, nucleic acids, proteins, and lipids to proximal cells. Although it is well recognized that OMVs can enter and release cargo inside host cells during infection, the mechanisms of host association and uptake are not well understood. This review highlights existing studies focusing on OMV‐host cell interactions and entry mechanisms, and how these entry routes affect cargo processing within the host. It further compares the wide range of methods currently used to dissect uptake mechanisms, and discusses potential sources of discrepancy regarding the mechanism of OMV uptake across different studies.
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Affiliation(s)
- Eloise J O'Donoghue
- University of Birmingham, Institute of Microbiology and Infection, School of Biosciences, Edgbaston, Birmingham, B15 2TT, UK
| | - Anne Marie Krachler
- University of Birmingham, Institute of Microbiology and Infection, School of Biosciences, Edgbaston, Birmingham, B15 2TT, UK.
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19
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Radomski N, Einenkel R, Müller A, Knittler MR. Chlamydia-host cell interaction not only from a bird's eye view: some lessons fromChlamydia psittaci. FEBS Lett 2016; 590:3920-3940. [DOI: 10.1002/1873-3468.12295] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Revised: 07/06/2016] [Accepted: 07/07/2016] [Indexed: 12/13/2022]
Affiliation(s)
- Nadine Radomski
- Friedrich-Loeffler-Institut; Institute of Immunology; Isle of Riems Germany
| | - Rebekka Einenkel
- Friedrich-Loeffler-Institut; Institute of Immunology; Isle of Riems Germany
| | - Anne Müller
- Friedrich-Loeffler-Institut; Institute of Immunology; Isle of Riems Germany
| | - Michael R Knittler
- Friedrich-Loeffler-Institut; Institute of Immunology; Isle of Riems Germany
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20
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Toledo A, Benach JL. Hijacking and Use of Host Lipids by Intracellular Pathogens. Microbiol Spectr 2015; 3:10.1128/microbiolspec.VMBF-0001-2014. [PMID: 27337282 PMCID: PMC5790186 DOI: 10.1128/microbiolspec.vmbf-0001-2014] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Indexed: 12/14/2022] Open
Abstract
Intracellular bacteria use a number of strategies to survive, grow, multiply, and disseminate within the host. One of the most striking adaptations that intracellular pathogens have developed is the ability to utilize host lipids and their metabolism. Bacteria such as Anaplasma, Chlamydia, or Mycobacterium can use host lipids for different purposes, such as a means of entry through lipid rafts, building blocks for bacteria membrane formation, energy sources, camouflage to avoid the fusion of phagosomes and lysosomes, and dissemination. One of the most extreme examples of lipid exploitation is Mycobacterium, which not only utilizes the host lipid as a carbon and energy source but is also able to reprogram the host lipid metabolism. Likewise, Chlamydia spp. have also developed numerous mechanisms to reprogram lipids onto their intracellular inclusions. Finally, while the ability to exploit host lipids is important in intracellular bacteria, it is not an exclusive trait. Extracellular pathogens, including Helicobacter, Mycoplasma, and Borrelia, can recruit and metabolize host lipids that are important for their growth and survival.Throughout this chapter we will review how intracellular and extracellular bacterial pathogens utilize host lipids to enter, survive, multiply, and disseminate in the host.
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Affiliation(s)
- Alvaro Toledo
- Department of Molecular Genetics and Microbiology, Stony Brook University, Center for Infectious Diseases at the Center for Molecular Medicine, Stony Brook, NY 11794
| | - Jorge L Benach
- Department of Molecular Genetics and Microbiology, Stony Brook University, Center for Infectious Diseases at the Center for Molecular Medicine, Stony Brook, NY 11794
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21
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Knittler MR, Sachse K. Chlamydia psittaci: update on an underestimated zoonotic agent. Pathog Dis 2014; 73:1-15. [PMID: 25853998 DOI: 10.1093/femspd/ftu007] [Citation(s) in RCA: 139] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2014] [Indexed: 12/16/2022] Open
Abstract
Chlamydia (C.) psittaci is an economically relevant pathogen in poultry and pet birds, where it causes psittacosis/ornithosis, and also a human pathogen causing atypical pneumonia after zoonotic transmission. Despite its well-documented prevalence, the agent has received less attention by researchers than other Chlamydia spp. in the last decades. In the present paper, we review recently published data on C. psittaci infection and attempt to single out characteristic features distinguishing it from related chlamydial agents. It is remarkable that C. psittaci is particularly efficient in disseminating in the host organism causing systemic disease, which occasionally can take a fulminant course. At the cellular level, the pathogen's broad host cell spectrum (from epithelial cells to macrophages), its rapid entry and fast replication, proficient use of intracellular transport routes to mitochondria and the Golgi apparatus, the pronounced physical association of chlamydial inclusions with energy-providing cell compartments, as well as the subversive regulation of host cell survival during productive and persistent states facilitate the characteristic efficient growth and successful host-to-host spread of C. psittaci. At the molecular level, the pathogen was shown to upregulate essential chlamydial genes when facing the host immune response. We hypothesize that this capacity, in concert with expression of specific effectors of the type III secretion system and efficient suppression of selected host defense signals, contributes to successful establishment of the infection in the host. Concerning the immunology of host-pathogen interactions, C. psittaci has been shown to distinguish itself by coping more efficiently than other chlamydiae with pro-inflammatory mediators during early host response, which can, to some extent, explain the effective evasion and adaptation strategies of this bacterium. We conclude that thorough analysis of the large number of whole-genome sequences already available will be essential to identify genetic markers of the species-specific features and trigger more in-depth studies in cellular and animal models to address such vital topics as treatment and vaccination.
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Affiliation(s)
- Michael R Knittler
- Institute of Immunology, Friedrich-Loeffler-Institut, Isle of Riems, 07743 Jena, Germany
| | - Konrad Sachse
- Institute of Molecular Pathogenesis, Friedrich-Loeffler-Institut, 07743 Jena, Germany
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22
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Asmat TM, Agarwal V, Saleh M, Hammerschmidt S. Endocytosis of Streptococcus pneumoniae via the polymeric immunoglobulin receptor of epithelial cells relies on clathrin and caveolin dependent mechanisms. Int J Med Microbiol 2014; 304:1233-46. [PMID: 25455218 DOI: 10.1016/j.ijmm.2014.10.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 09/18/2014] [Accepted: 10/05/2014] [Indexed: 12/17/2022] Open
Abstract
Colonization of Streptococcus pneumoniae (pneumococci) is a prerequisite for bacterial dissemination and their capability to enter the bloodstream. Pneumococci have evolved various successful strategies to colonize the mucosal epithelial barrier of humans. A pivotal mechanism of host cell invasion implicated with invasive diseases is promoted by the interaction of pneumococcal PspC with the polymeric Ig-receptor (pIgR). However, the mechanism(s) of pneumococcal endocytosis and the intracellular route of pneumococci upon uptake by the PspC-pIgR-interaction are not known. Here, we demonstrate by using a combination of pharmacological inhibitors and genetics interference approaches the involvement of active dynamin-dependent caveolae and clathrin-coated vesicles for pneumococcal uptake via the PspC-pIgR mechanism. Depleting cholesterol from host cell membranes and disruption of lipid microdomains impaired pneumococcal internalization. Moreover, chemical inhibition of clathrin or functional inactivation of dynamin, caveolae or clathrin by RNA interference significantly affected pneumococcal internalization suggesting that clathrin-mediated endocytosis (CME) and caveolae are involved in the bacterial uptake process. Confocal fluorescence microscopy of pIgR-expressing epithelial cells infected with pneumococci or heterologous Lactococcus lactis expressing PspC demonstrated bacterial co-localization with fluorescent-tagged clathrin and early as well as recycling or late endosomal markers such as Lamp1, Rab5, Rab4, and Rab7, respectively. In conclusion these data suggest that PspC-promoted uptake is mediated by both CME and caveolae. After endocytosis pneumococci are routed via the endocytic pathway into early endosomes and are then sorted into recycling or late endosomes, which can result in pneumococcal killing in phagolysosomes or transcytosis via recycling endosomes.
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Affiliation(s)
- Tauseef M Asmat
- Department Genetics of Microorganisms, Interfaculty Institute for Genetics and Functional Genomics, Ernst-Moritz-Arndt Universität Greifswald, Friedrich-Ludwig-Jahn-Strasse 15a, D-17487 Greifswald, Germany; Pediatric Infectious Diseases, Department of Pediatrics, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Vaibhav Agarwal
- Department Genetics of Microorganisms, Interfaculty Institute for Genetics and Functional Genomics, Ernst-Moritz-Arndt Universität Greifswald, Friedrich-Ludwig-Jahn-Strasse 15a, D-17487 Greifswald, Germany; Department of Laboratory Medicine, Medical Protein Chemistry, Malmö University Hospital, Lund University, Malmö, Sweden
| | - Malek Saleh
- Department Genetics of Microorganisms, Interfaculty Institute for Genetics and Functional Genomics, Ernst-Moritz-Arndt Universität Greifswald, Friedrich-Ludwig-Jahn-Strasse 15a, D-17487 Greifswald, Germany
| | - Sven Hammerschmidt
- Department Genetics of Microorganisms, Interfaculty Institute for Genetics and Functional Genomics, Ernst-Moritz-Arndt Universität Greifswald, Friedrich-Ludwig-Jahn-Strasse 15a, D-17487 Greifswald, Germany.
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23
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Mehlitz A, Rudel T. Modulation of host signaling and cellular responses by Chlamydia. Cell Commun Signal 2013; 11:90. [PMID: 24267514 PMCID: PMC4222901 DOI: 10.1186/1478-811x-11-90] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 11/19/2013] [Indexed: 01/24/2023] Open
Abstract
Modulation of host cell signaling and cellular functions is key to intracellular survival of pathogenic bacteria. Intracellular growth has several advantages e.g. escape from the humoral immune response and access to a stable nutrient rich environment. Growth in such a preferred niche comes at the price of an ongoing competition between the bacteria and the host as well as other microbes that compete for the very same host resources. This requires specialization and constant evolution of dedicated systems for adhesion, invasion and accommodation. Interestingly, obligate intracellular bacteria of the order Chlamydiales have evolved an impressive degree of control over several important host cell functions. In this review we summarize how Chlamydia controls its host cell with a special focus on signal transduction and cellular modulation.
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Affiliation(s)
- Adrian Mehlitz
- University of Wuerzburg, Biocenter, Department of Microbiology, Am Hubland, D-97074, Wuerzburg, Germany.
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24
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Involvement of lipid rafts in the budding-like exit of Orientia tsutsugamushi. Microb Pathog 2013; 63:37-43. [DOI: 10.1016/j.micpath.2013.06.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 06/05/2013] [Indexed: 01/20/2023]
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25
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Feng H, Guo W, Han J, Li XA. Role of caveolin-1 and caveolae signaling in endotoxemia and sepsis. Life Sci 2013; 93:1-6. [PMID: 23727353 DOI: 10.1016/j.lfs.2013.05.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 05/09/2013] [Accepted: 05/14/2013] [Indexed: 12/28/2022]
Abstract
Caveolae, plasma membrane invaginations of 60-80nm in diameter, are a subset of lipid rafts enriched in cholesterol and sphingolipids. Caveolae are expressed in various tissues and cell types, such as endothelial cells, macrophages, neutrophils and adipocytes. The functions of caveolae are diverse and include endocytosis, transcytosis, potocytosis, calcium signaling, and regulation of various signaling events. Although growing evidence has increased our understanding of caveolae function, the role of caveolae in sepsis is still a controversial issue. In this review, we present a number of studies addressing caveolae and sepsis and describe the signaling pathways involved, including the LPS-eNOS-TLR4-NFκB, MKK3/p38 MAPK, cPLA2/p38 MAPK, STAT3/NFκB and IL-1β-IL-1R1 pathways. Different studies using endotoxemia and bacteremia animal models have provided distinct conclusions about the function of caveolae, and we discuss these inconsistencies. Taken together, the current data suggest that the function of caveolae in sepsis, which involves a number of signaling pathways, is complex and warrants further studies.
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Affiliation(s)
- Hong Feng
- Department of Tumor Research and Therapy Center, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, China
| | - Wen Guo
- Taian Central Hospital, Taian, Shandong 271000, China
| | - Junqing Han
- Department of Tumor Research and Therapy Center, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, China
| | - Xiang-An Li
- Department of Pediatrics, University of Kentucky College of Medicine, Lexington, KY 40536, United States.
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26
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Bastidas RJ, Elwell CA, Engel JN, Valdivia RH. Chlamydial intracellular survival strategies. Cold Spring Harb Perspect Med 2013; 3:a010256. [PMID: 23637308 DOI: 10.1101/cshperspect.a010256] [Citation(s) in RCA: 156] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Chlamydia trachomatis is the most common sexually transmitted bacterial pathogen and the causative agent of blinding trachoma. Although Chlamydia is protected from humoral immune responses by residing within remodeled intracellular vacuoles, it still must contend with multilayered intracellular innate immune defenses deployed by its host while scavenging for nutrients. Here we provide an overview of Chlamydia biology and highlight recent findings detailing how this vacuole-bound pathogen manipulates host-cellular functions to invade host cells and maintain a replicative niche.
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Affiliation(s)
- Robert J Bastidas
- Department of Molecular Genetics and Microbiology, Center for Microbial Pathogenesis, Duke University Medical Center, Durham, NC 27710, USA
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27
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Nitric oxide induces segregation of decay accelerating factor (DAF or CD55) from the membrane lipid-rafts and its internalization in human endometrial cells. Cell Biol Int 2013; 36:901-7. [PMID: 22574734 DOI: 10.1042/cbi20110586] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Recent studies suggest that DAF (decay accelerating factor), a complement regulatory protein, present in lipid rafts, is utilized by Dr fimbriated Escherichia coli for their binding and internalization. Previous studies in our laboratory have shown that NO (nitric oxide) can reduce the invasion of Dr(+) E. coli and the severity of uterine infection in pregnant rats. Also, the expression level of DAF both at the mRNA and protein levels has been shown to be reduced by NO. Therefore NO mediated down-regulation of DAF appears to be an important factor in reducing the susceptibility to E. coli infection. However, it is unclear if NO can actually modulate the membrane association of DAF and therefore initial bacterial binding to cells. We found that NO induces the delocalization of DAF from the G(M1)-rich lipid rafts. Using biochemical and cell biological approaches in a uterine epithelial cell model (Ishikawa cells), DAF accumulates in caveolae upon exposure to NO. Interaction of DAF with the caveolar protein, caveolin1, leads to their internalization by endosomes. NO-induced delocalization of DAF from the lipid raft and its accumulation in caveolae are mediated through a cGMP (cyclic guanosine monophosphate) pathway. The acute localized synthesis of NO and its influence on DAF localization may represent an important unrecognized phenomenon of host defence against Dr(+) E. coli bacteria, as well as many disease conditions that involve complement system.
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28
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Chlamydia pneumoniae entry into epithelial cells by clathrin-independent endocytosis. Microb Pathog 2011; 52:157-64. [PMID: 22203235 DOI: 10.1016/j.micpath.2011.12.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Revised: 12/08/2011] [Accepted: 12/14/2011] [Indexed: 11/24/2022]
Abstract
A gram-negative obligate intracellular bacterium, Chlamydia pneumoniae, is a common respiratory pathogen. Here, we examined the invasion and attachment of C. pneumoniae K6 into nonphagocytic HL epithelial cell line by manipulating host plasma membranes by using cholesterol-depleting methyl-beta-cyclodextrin (MβCD) and cholesterol-loading MβCD complexed cholesterol (chol-MβCD). The invasion was attenuated by MβCD-treatment while chol-MβCD augmented the attachment and invasion. In addition, the invasion was inhibited by cholesterol sequestering reagents, nystatin and filipin. Furthermore, exposure of host cells to sphingomyelinase inhibited the invasion. RNA interference was used to assay the role of clathrin and human scavenger receptor B, type I (SR-BI) in the entry of C. pneumoniae into A549 lung epithelial adenocarcinoma cells. In contrast to Chlamydia trachomatis L2, the entry of C. pneumoniae was found to be independent of clathrin. In addition, the entry was found to be SR-BI-independent, but interestingly, the chlamydial growth was attenuated in the SR-BI-silenced cells. These findings suggest that the attachment and invasion of C. pneumoniae into nonphagocytic epithelial cells is dependent on the formation of cholesterol- and sphingomyelin-rich plasma membrane microdomains, and the entry is a clathrin-independent process. In addition, our data indicate that SR-BI supports the growth of C. pneumoniae in epithelial cells.
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29
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Rosazza C, Phez E, Escoffre JM, Cézanne L, Zumbusch A, Rols MP. Cholesterol implications in plasmid DNA electrotransfer: Evidence for the involvement of endocytotic pathways. Int J Pharm 2011; 423:134-43. [PMID: 21601622 DOI: 10.1016/j.ijpharm.2011.05.024] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Revised: 05/05/2011] [Accepted: 05/05/2011] [Indexed: 10/18/2022]
Abstract
The delivery of therapeutic molecules such as plasmid DNA in cells and tissues by means of electric fields holds great promise for anticancer treatment. To allow for their therapeutic action, the molecules have first to traverse the cell membrane. The mechanisms by which the electrotransferred pDNA interacts with and crosses the plasma membrane are not yet fully explained. The aim of this study is to unravel the role of cholesterol during gene electrotransfer in cells. We performed cholesterol depletion experiments and measured its effects on various steps of the electroporation process. The first two steps consisting of electropermeabilization of the plasma membrane and of pDNA interaction with it were not affected by cholesterol depletion. In contrast, gene expression decreased. Colocalization studies with endocytotic markers showed that pDNA is endocytosed with concomitant clathrin- and caveolin/raft-mediated endocytosis. Cholesterol might be involved in the pDNA translocation through the plasma membrane. This is the first direct experimental evidence of the occurrence of endocytosis in gene electrotransfer.
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Affiliation(s)
- Christelle Rosazza
- Department of Structural Biology and Biophysics, CNRS, Institut de Pharmacologie et de Biologie Structurale, 205 Route de Narbonne, F-31077 Toulouse, France
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Hartlova A, Cerveny L, Hubalek M, Krocova Z, Stulik J. Membrane rafts: a potential gateway for bacterial entry into host cells. Microbiol Immunol 2010; 54:237-45. [PMID: 20377752 DOI: 10.1111/j.1348-0421.2010.00198.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Pathogenic bacteria have developed various mechanisms to evade host immune defense systems. Invasion of pathogenic bacteria requires interaction of the pathogen with host receptors, followed by activation of signal transduction pathways and rearrangement of the cytoskeleton to facilitate bacterial entry. Numerous bacteria exploit specialized plasma membrane microdomains, commonly called membrane rafts, which are rich in cholesterol, sphingolipids and a special set of signaling molecules which allow entry to host cells and establishment of a protected niche within the host. This review focuses on the current understanding of the raft hypothesis and the means by which pathogenic bacteria subvert membrane microdomains to promote infection.
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Affiliation(s)
- Anetta Hartlova
- Centre of Advanced Studies, Faculty of Military Health Sciences, University of Defense, Hradec Kralove, Czech Republic.
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31
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Abdul-Sater AA, Saïd-Sadier N, Padilla EV, Ojcius DM. Chlamydial infection of monocytes stimulates IL-1beta secretion through activation of the NLRP3 inflammasome. Microbes Infect 2010; 12:652-661. [PMID: 20434582 DOI: 10.1016/j.micinf.2010.04.008] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2010] [Accepted: 04/20/2010] [Indexed: 12/31/2022]
Abstract
Chlamydia trachomatis infections represent the leading cause of bacterial sexually-transmitted disease in the United States and can cause serious tissue damage leading to infertility and ectopic pregnancies in women. Inflammation and hence the innate immune response to chlamydial infection contributes significantly to tissue damage, particularly by secreting proinflammatory cytokines such as interleukin (IL)-1beta from monocytes, macrophages and dendritic cells. Here we demonstrate that C. trachomatis or Chlamydia muridarum infection of a monocytic cell line leads to caspase-1 activation and IL-1beta secretion through a process requiring the NLRP3 inflammasome. Thus, secretion of IL-1beta decreased significantly when cells were depleted of NLRP3 or treated with the anti-inflammatory inhibitors parthenolide or Bay 11-7082, which inhibit inflammasomes and the transcription factor NF-kappaB. As for other infections causing NRLP3 inflammasome assembly, caspase-1 activation in monocytes is triggered by potassium efflux and reactive oxygen species production. However, anti-oxidants inhibited IL-1beta secretion only partially. Atypically for a bacterial infection, caspase-1 activation during chlamydial infection also involves partially the spleen tyrosine kinase (Syk), which is usually associated with a pathogen recognition receptor for fungal pathogens. Secretion of IL-1beta during infection by many bacteria requires both microbial products from the pathogen and an exogenous danger signal, but chlamydial infection provides both the pathogen-associated molecular patterns and danger signals necessary for IL-1beta synthesis and its secretion from human monocytes. Use of inhibitors that target the inflammasome in animals should therefore dampen inflammation during chlamydial infection.
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Affiliation(s)
- Ali A Abdul-Sater
- Health Sciences Research Institute and School of Natural Sciences, University of California, Merced, CA 95343, USA
| | - Najwane Saïd-Sadier
- Health Sciences Research Institute and School of Natural Sciences, University of California, Merced, CA 95343, USA.,Institut Jacques Monod, Université Paris Diderot, 75205 Paris cedex 13, France
| | - Eduardo V Padilla
- Health Sciences Research Institute and School of Natural Sciences, University of California, Merced, CA 95343, USA
| | - David M Ojcius
- Health Sciences Research Institute and School of Natural Sciences, University of California, Merced, CA 95343, USA.,Institut Jacques Monod, Université Paris Diderot, 75205 Paris cedex 13, France
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CFTR is required for cellular entry and internalization ofChlamydia trachomatis. Cell Biol Int 2010; 34:593-600. [DOI: 10.1042/cbi20090227] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Vieira FS, Corrêa G, Einicker-Lamas M, Coutinho-Silva R. Host-cell lipid rafts: a safe door for micro-organisms? Biol Cell 2010; 102:391-407. [PMID: 20377525 PMCID: PMC7161784 DOI: 10.1042/bc20090138] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2010] [Accepted: 02/10/2010] [Indexed: 12/20/2022]
Abstract
The lipid raft hypothesis proposed that these microdomains are small (10-200 nM), highly dynamic and enriched in cholesterol, glycosphingolipids and signalling phospholipids, which compartmentalize cellular processes. These membrane regions play crucial roles in signal transduction, phagocytosis and secretion, as well as pathogen adhesion/interaction. Throughout evolution, many pathogens have developed mechanisms to escape from the host immune system, some of which are based on the host membrane microdomain machinery. Thus lipid rafts might be exploited by pathogens as signalling and entry platforms. In this review, we summarize the role of lipid rafts as players in the overall invasion process used by different pathogens to escape from the host immune system.
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Affiliation(s)
- Flávia Sarmento Vieira
- Laboratório de Imunofisiologia, Universidade Federal do Rio de Janeiro, Instituto de Biofísica Carlos Chagas Filho, CCS, Rio de Janeiro, RJ, Brazil
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Hartlova A, Cerveny L, Hubalek M, Krocova Z, Stulik J. Membrane rafts: a potential gateway for bacterial entry into host cells. Microbiol Immunol 2009. [DOI: 10.1111/j.1348-0421.2009.00198.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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35
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Wang M, Hajishengallis G. Lipid raft-dependent uptake, signalling and intracellular fate of Porphyromonas gingivalis in mouse macrophages. Cell Microbiol 2008; 10:2029-42. [PMID: 18547335 DOI: 10.1111/j.1462-5822.2008.01185.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Lipid rafts are cholesterol-enriched microdomains involved in cellular trafficking and implicated as portals for certain pathogens. We sought to determine whether the oral pathogen Porphyromonas gingivalis enters macrophages via lipid rafts, and if so, to examine the impact of raft entry on its intracellular fate. Using J774A.1 mouse macrophages, we found that P. gingivalis colocalizes with lipid rafts in a cholesterol-dependent way. Depletion of cellular cholesterol using methyl-beta-cyclodextrin resulted in about 50% inhibition of P. gingivalis uptake, although this effect was reversed by cholesterol reconstitution. The intracellular survival of P. gingivalis was dramatically inhibited in cholesterol-depleted cells relative to untreated or cholesterol-reconstituted cells, even when infections were adjusted to allow equilibration of the initial intracellular bacterial load. P. gingivalis thus appeared to exploit raft-mediated uptake for promoting its survival. Consistent with this, lipid raft disruption enhanced the colocalization of internalized P. gingivalis with lysosomes. In contrast, raft disruption did not affect the expression of host receptors interacting with P. gingivalis, although it significantly inhibited signal transduction. In summary, P. gingivalis uses macrophage lipid rafts as signalling and entry platforms, which determine its intracellular fate to the pathogen's own advantage.
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Affiliation(s)
- Min Wang
- Department of Periodontics/Oral Health and Systemic Disease, University of Louisville Health Sciences Center, Louisville, KY 40292, USA
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Nishiyama A, Shinohara T, Pantuso T, Tsuji S, Yamashita M, Shinohara S, Myrvik QN, Henriksen RA, Shibata Y. Depletion of cellular cholesterol enhances macrophage MAPK activation by chitin microparticles but not by heat-killed Mycobacterium bovis BCG. Am J Physiol Cell Physiol 2008; 295:C341-9. [PMID: 18524942 DOI: 10.1152/ajpcell.00446.2007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
When macrophages phagocytose chitin (N-acetyl-d-glucosamine polymer) microparticles, mitogen-activated protein kinases (MAPK) are immediately activated, followed by the release of Th1 cytokines, but not IL-10. To determine whether phagocytosis and macrophage activation in response to chitin microparticles are dependent on membrane cholesterol, RAW264.7 macrophages were treated with methyl-beta-cytodextrin (MBCD) and stimulated with chitin. These results were compared with the corresponding effects of bacterial components including heat-killed (HK) Mycobacterium bovis bacillus Calmette-Guèrin (BCG) and an oligodeoxynucleotide (ODN) of bacterial DNA (CpG-ODN). The MBCD treatment did not alter chitin binding or the phagocytosis of chitin particles 20 min after stimulation. At the same time, however, chitin-induced phosphorylation of cellular MAPK was accelerated and enhanced in an MBCD dose-dependent manner. The increased phosphorylation was also observed for chitin phagosome-associated p38 and ERK1/2. In contrast, CpG-ODN and HK-BCG induced activation of MAPK in MBCD-treated cells at levels comparable to, or only slightly more than, those of control cells. We also found that MBCD treatment enhanced the production of tumor necrosis factor-alpha (TNF-alpha) and the expression of cyclooxygenase-2 (COX-2) in response to chitin microparticles. In neither MBCD- nor saline-treated macrophages, did chitin particles induce detectable IL-10 mRNA synthesis. CpG-ODN induced TNF-alpha production, and COX-2 expression were less sensitive to MBCD treatment. Among the agonists studied, our results indicate that macrophage activation by chitin microparticles was most sensitive to cholesterol depletion, suggesting that membrane structures integrated by cholesterol are important for physiological regulation of chitin microparticle-induced cellular activation.
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Affiliation(s)
- Akihito Nishiyama
- Department of Biomedical Sciences, Florida Atlantic Univ., 777 Glades Rd., Boca Raton, FL 33431-0991, USA
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Fadel S, Eley A. Is lipopolysaccharide a factor in infectivity of Chlamydia trachomatis? J Med Microbiol 2008; 57:261-266. [PMID: 18287286 DOI: 10.1099/jmm.0.47237-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Lipopolysaccharide (LPS) is a major surface component of Chlamydia trachomatis, as with all Gram-negative bacteria. The effect of C. trachomatis LPS on C. trachomatis infectivity of human epithelial cells was investigated. C. trachomatis LPS and C. trachomatis LPS antibody significantly reduced infectivity, mostly in a dose-dependent manner. As the structure of LPS in C. trachomatis is simple and consists only of lipid A and 3-deoxy-D-manno-octulosonic acid (Kdo), we investigated whether lipid A or Kdo was inhibitory to chlamydial infectivity. Polymyxin B, as a lipid A inhibitor, and Kdo considerably reduced C. trachomatis infectivity. With all the LPS inhibitors used, there was greater inhibition against serovar E than serovar LGV. These results suggest a role for LPS in chlamydial infectivity. Elucidation of how LPS acts in infectivity and identification of host-cell receptors would help in understanding pathogenicity.
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Affiliation(s)
- Sanaa Fadel
- Henry Wellcome Laboratories for Medical Research, Unit of Infection and Immunity, School of Medicine and Biomedical Sciences, University of Sheffield Medical School, Beech Hill Road, Sheffield S10 2RX, UK
| | - Adrian Eley
- Henry Wellcome Laboratories for Medical Research, Unit of Infection and Immunity, School of Medicine and Biomedical Sciences, University of Sheffield Medical School, Beech Hill Road, Sheffield S10 2RX, UK
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Jong A, Wu CH, Shackleford GM, Kwon-Chung KJ, Chang YC, Chen HM, Ouyang Y, Huang SH. Involvement of human CD44 during Cryptococcus neoformans infection of brain microvascular endothelial cells. Cell Microbiol 2008; 10:1313-26. [PMID: 18248627 DOI: 10.1111/j.1462-5822.2008.01128.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Pathogenic yeast Cryptococcus neoformans causes devastating cryptococcal meningoencephalitis. Our previous studies demonstrated that C. neoformans hyaluronic acid was required for invasion into human brain microvascular endothelial cells (HBMEC), which constitute the blood-brain barrier. In this report, we demonstrate that C. neoformans hyaluronic acid interacts with CD44 on HBMEC. Our results suggest that HBMEC CD44 is a primary receptor during C. neoformans infection, based on the following observations. First, anti-CD44 neutralizing antibody treatment was able to significantly reduce C. neoformans association with HBMEC. Second, C. neoformans association was considerably impaired using either CD44-knock-down HBMEC or C. neoformans hyaluronic acid-deficient strains. Third, overexpression of CD44 in HBMEC increased their association activity towards C. neoformans. Fourth, confocal microscopic images showed that CD44 was enriched at and around the C. neoformans association sites. Fifth, upon C. neoformans and HBMEC engagement, a subpopulation of CD44 and actin translocated to the host membrane rafts. Our results highlight the interactions between C. neoformans hyaluronic acid and host CD44 and the dynamic results of these interactions, which may represent events during the adhesion and entry of C. neoformans at HBMEC membrane rafts.
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Affiliation(s)
- Ambrose Jong
- Division of Hematology-Oncology, The Saban Research Institute, Childrens Hospital Los Angeles, Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90027, USA.
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39
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Abstract
The mechanisms of entry for the obligate intracellular bacterium C. trachomatis were examined by functional disruption of proteins essential for various modes of entry. RNA interference was used to disrupt proteins with established roles in clathrin-mediated endocytosis (clathrin heavy chain, dynamin-2, heat shock 70-kDa protein 8, Arp2, cortactin, and calmodulin), caveola-mediated endocytosis (caveolin-1, dynamin-2, Arp2, NSF, and annexin II), phagocytosis (RhoA, dynamin-2, Rac1, and Arp2), and macropinocytosis (Pak1, Rac1, and Arp2). Comparative quantitative PCR analysis was performed on small interfering RNA-transfected HeLa cells to accurately determine the extent of C. trachomatis entry after these treatments. Key structural and regulatory factors associated with clathrin-mediated endocytosis were found to be involved in Chlamydia entry, whereas those for caveola-mediated endocytosis, phagocytosis, and macropinocytosis were not. Thus, clathrin and its coordinate accessory factors were required for entry of C. trachomatis, although additional, uncharacterized mechanisms are also utilized.
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Affiliation(s)
- Kevin Hybiske
- Division of Infectious Diseases, School of Public Health, 140 Warren Hall, University of California-Berkeley, Berkeley, CA 94720, USA
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Guseva NV, Dessus-Babus S, Moore CG, Whittimore JD, Wyrick PB. Differences in Chlamydia trachomatis serovar E growth rate in polarized endometrial and endocervical epithelial cells grown in three-dimensional culture. Infect Immun 2007; 75:553-64. [PMID: 17088348 PMCID: PMC1828515 DOI: 10.1128/iai.01517-06] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2006] [Revised: 10/17/2006] [Accepted: 10/30/2006] [Indexed: 12/28/2022] Open
Abstract
In vitro studies of obligate intracellular chlamydia biology and pathogenesis are highly dependent on the use of experimental models and growth conditions that mimic the mucosal architecture and environment these pathogens encounter during natural infections. In this study, the growth of Chlamydia trachomatis genital serovar E was monitored in mouse fibroblast McCoy cells and compared to more relevant host human epithelial endometrium-derived HEC-1B and cervix-derived HeLa cells, seeded and polarized on collagen-coated microcarrier beads, using a three-dimensional culture system. Microscopy analysis of these cell lines prior to infection revealed morphological differences reminiscent of their in vivo architecture. Upon infection, early chlamydial inclusion distribution was uniform in McCoy cells but patchy in both epithelial cell lines. Although no difference in chlamydial attachment to or entry into the two genital epithelial cell lines was noted, active bacterial genome replication and transcription, as well as initial transformation of elementary bodies to reticulate bodies, were detected earlier in HEC-1B than in HeLa cells, suggesting a faster growth, which led to higher progeny counts and titers in HEC-1B cells upon completion of the developmental cycle. Chlamydial development in the less relevant McCoy cells was very similar to that in HeLa cells, although higher progeny counts were obtained. In conclusion, this three-dimensional bead culture system represents an improved model for harvesting large quantities of infectious chlamydia progeny from their more natural polarized epithelial host cells.
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Affiliation(s)
- Natalia V Guseva
- Department of Microbiology, East Tennessee State University, James H. Quillen College of Medicine, Johnson City, TN 37614, USA
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Riethmüller J, Riehle A, Grassmé H, Gulbins E. Membrane rafts in host-pathogen interactions. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2006; 1758:2139-47. [PMID: 17094939 DOI: 10.1016/j.bbamem.2006.07.017] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2006] [Revised: 06/13/2006] [Accepted: 07/18/2006] [Indexed: 02/09/2023]
Abstract
Central elements in the infection of mammalian cells with viral, bacterial and parasitic pathogens include the adhesion of the pathogen to surface receptors of the cell, recruitment of additional receptor proteins to the infection-site, a re-organization of the membrane and, in particular, the intracellular signalosome. Internalization of the pathogen results in the formation of a phagosome that is supposed to fuse with lysosomes to form phagolysosomes, which serve the degradation of the pathogen, an event actively prevented by some pathogens. In summary, these changes in the infected cell permit pathogens to trigger apoptosis (for instance of macrophages paralysing the initial immune response), to invade the cell and/or to survive in the cell, but they also serve the mammalian cell to defeat the infection, for instance by activation of transcription factors and the release of cytokines. Distinct membrane domains in the plasma membrane and intracellular vesicles that are mainly composed of sphingolipids and cholesterol or enriched with the sphingolipid ceramide, are critically involved in all of these events occurring during the infection. These membrane structures are therefore very attractive targets for novel drugs to interfere with bacterial, viral and parasitic infections.
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Affiliation(s)
- Joachim Riethmüller
- Children's Hospital, University of Tuebingen, Hoppe-Seyler Str. 1, 72076 Tuebingen, Germany
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42
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Manunta M, Nichols BJ, Tan PH, Sagoo P, Harper J, George AJT. Gene delivery by dendrimers operates via different pathways in different cells, but is enhanced by the presence of caveolin. J Immunol Methods 2006; 314:134-46. [PMID: 16893551 DOI: 10.1016/j.jim.2006.06.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2005] [Revised: 04/13/2006] [Accepted: 06/09/2006] [Indexed: 01/22/2023]
Abstract
In order to optimise and improve the efficacy of transfection mediated by dendrimers, it is essential to fully understand the mechanisms of cell entry and intracellular trafficking by these complexes. Previously, we have shown that gene delivery by dendrimers is dependent from cholesterol and membrane rafts. The inhibition of transfection by treatment with filipin III suggested that gene delivery might be occurring by a caveolin-dependent pathway. We therefore investigated the internalisation and transfection properties of dendriplexes using cell lines (HeLa and HepG2) that express few caveolae. We show that, in contrast to other cells, cholesterol depletion does not affect the ability of dendriplexes to transfect these cells. Inhibition of clathrin-independent, phagocytic and macropinocytic pathways also failed to inhibit transfection of these cells and endothelial cells. However, overexpression of caveolin 1 resulted in an increased rate of dendriplex uptake into HeLa, HepG2 and endothelial cells, and increased transfection efficiency. Furthermore, in endothelial cells, confocal microscopy demonstrated colocalisation of dendriplexes and caveolin 1. These data highlight that dendriplexes may use different internalisation pathways in different cells, and that caveolae form a preferential route for gene delivery by this non-viral vector.
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Affiliation(s)
- Maria Manunta
- Department of Immunology, Division of Medicine, Faculty of Medicine, Imperial College London, Hammersmith Hospital, Du Cane Road, London, W12 0NN, United Kingdom
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Abstract
Chlamydia are widespread bacteria that grow in human and animal cells. They enter their host cell, establish an intracellular environment favourable for their multiplication and finally exit the host cell. A combination of host cell factors and of bacterial proteins contribute to pathogen entry. Recent advances have shed new light on the entry mechanism, following attachment. Here we review recent data concerning endocytosis, host cell signalling, proteins secreted by the bacteria, the actin cytoskeleton in entry and the involvement of small GTPases.
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Affiliation(s)
- Alice Dautry-Varsat
- Unité de Biologie des Interactions Cellulaires, Institut Pasteur, URA CNRS 2582, 25 rue du Docteur Roux, 75724 Paris Cedex 15, France.
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Abstract
Accumulating reports document the use by pathogens of cholesterol-enriched lipid microdomains, often called lipid rafts, as cell surface platforms to interact, bind and possibly enter into host cells. The challenge is now to understand what could be the functional role of these domains during pathogen invasion. Are they hijacked as general clustering devices for cellular binding sites and/or do they have other roles? In particular, is their cell signalling capacity activated and used by pathogens? In reverse, could lipid rafts activate bacterial mechanisms required for invasion? These issues will be discussed after an introduction on the current view on lipid rafts.
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Affiliation(s)
- Frank Lafont
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Switzerland
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Wang XM, Kim HP, Song R, Choi AMK. Caveolin-1 confers antiinflammatory effects in murine macrophages via the MKK3/p38 MAPK pathway. Am J Respir Cell Mol Biol 2005; 34:434-42. [PMID: 16357362 PMCID: PMC2644205 DOI: 10.1165/rcmb.2005-0376oc] [Citation(s) in RCA: 126] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Caveolin-1 has been reported to regulate apoptosis, lipid metabolism, and endocytosis in macrophages. In the present study, we demonstrate that caveolin-1 can act as a potent immunomodulatory molecule. We first observed caveolin-1 expression in murine alveolar macrophages by Western blotting and immunofluorescence microscopy. Loss-of-function experiments using small interfering RNA showed that down regulating caveolin-1 expression in murine alveolar and peritoneal macrophages increased LPS-induced proinflammatory cytokine TNF-alpha and IL-6 production but decreased anti-inflammatory cytokine IL-10 production. Gain-of-function experiments demonstrated that overexpression of caveolin-1 in RAW264.7 cells decreased LPS-induced TNF-alpha and IL-6 production and augmented IL-10 production. p38 mitogen-activated protein kinase (MAPK) phosphorylation was increased by overexpressing caveolin-1 in RAW264.7 cells, whereas c-Jun N-terminal kinase, extracellular signal-regulated kinase MAPK, and Akt phosphorylation were inhibited. The antiinflammatory modulation of LPS-induced cytokine production by caveolin-1 was significantly abrogated by the administration of p38 inhibitor SB203580 in RAW264.7 cells. Peritoneal macrophages isolated from MKK3 null mice did not demonstrate any modulation of LPS-induced cytokine production by caveolin-1. LPS-induced activation of NF-kappaB and AP-1 determined by electrophoretic mobility shift assay were significantly reduced by overexpressing caveolin-1 in RAW264.7 cells. The reductions were attenuated by the administration of p38 inhibitor SB203580. Taken together, our data suggest that caveolin-1 acts as a potent immunomodulatory effector molecule in immune cells and that the regulation of LPS-induced cytokine production by caveolin-1 involves the MKK3/p38 MAPK pathway.
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Affiliation(s)
- Xiao Mei Wang
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, 3459 Fifth Avenue, MUH 628, Pittsburgh, PA 15213, USA
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Schlott T, Eiffert H, Bohne W, Landgrebe J, Brunner E, Spielbauer B, Knight B. Chlamydia trachomatis modulates expression of tumor suppressor gene caveolin-1 and oncogene C-myc in the transformation zone of non-neoplastic cervical tissue. Gynecol Oncol 2005; 98:409-19. [PMID: 16005053 DOI: 10.1016/j.ygyno.2005.04.034] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2005] [Revised: 04/05/2005] [Accepted: 04/20/2005] [Indexed: 11/23/2022]
Abstract
OBJECTIVES The obligate intracellular bacterium Chlamydia trachomatis is frequently found in association with benign proliferative, pre-neoplastic and malignant changes in cervical epithelium. The present study addresses the possible role of C. trachomatis infection of the uterine cervix in modulating human cancer gene expression. METHODS RNA was extracted from both C. trachomatis infected and non-infected human fibroblast cultures treated with ITFgamma. The extracted RNA was used for cDNA microarrays carrying 33,000 human genes to detect abnormal gene expression induced by Chlamydia. Forty specimens of cervix dissected from the transformation zone had previously tested negative for HPV and positive for C. trachomatis by standard DNA PCR (20). These samples were subjected to RT-PCR to detect the expression of the abnormal genes induced by Chlamydia infection. RESULTS The ITFgamma-induced, non-replicative Chlamydia-infected fibroblast cultures showed significant modulation of gene expression. The cultures showed a 2-fold decrease in the expression of the gene coding for the tumor suppressor caveolin-1, and increased expression of the oncogene C-myc, a promoter of cervical carcinogenesis. In tissues from the Chlamydia-infected cervical transformation zone, real-time RT-PCR demonstrated a highly significant average 4.7-fold reduction of caveolin-1 mRNA (P < or = 0.0001) and an average 2.1-fold increase in C-myc (P < 0.05). CONCLUSIONS Human ITFgamma-treated fibroblasts as well as non-neoplastic cervical tissues responded to C. trachomatis with a strong down-regulation of caveolin-1 mRNA and a light up-regulation of C-myc mRNA. These changes were independent of the HPV high-risk types. This study reveals possible mechanisms by which C. trachomatis infection may contribute to neoplastic changes in the transformation of uterine cervix. These possible mechanisms require further evaluation.
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Affiliation(s)
- Thilo Schlott
- Department of Pathology, Georg August University, Robert-Koch-Str 40, D-37075 Goettingen, Germany.
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Zaas DW, Duncan M, Rae Wright J, Abraham SN. The role of lipid rafts in the pathogenesis of bacterial infections. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2005; 1746:305-13. [PMID: 16289370 DOI: 10.1016/j.bbamcr.2005.10.003] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2005] [Revised: 10/09/2005] [Accepted: 10/11/2005] [Indexed: 12/22/2022]
Abstract
Numerous pathogens have evolved mechanisms of co-opting normal host endocytic machinery as a means of invading host cells. While numerous pathogens have been known to enter cells via traditional clathrin-coated pit endocytosis, a growing number of viral and bacterial pathogens have been recognized to invade host cells via clustered lipid rafts. This review focuses on several bacterial pathogens that have evolved several different mechanisms of co-opting clustered lipid rafts to invade host cells. Although these bacteria have diverse clinical presentations and many differences in their pathogenesis, they each depend on the integrity of clustered lipid rafts for their intracellular survival. Bacterial invasion via clustered lipid rafts has been recognized as an important virulence factor for a growing number of bacterial pathogens in their battle against host defenses.
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Affiliation(s)
- David W Zaas
- Duke University Medical Center, Box 3221, Jones Building Room 255, Research Drive, Durham, NC 27710, USA.
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Abstract
During invasion by Toxoplasma gondii, host cell transmembrane proteins are excluded from the forming parasitophorous vacuole membrane (PVM) by the tight apposition of host and parasite cellular membranes. Previous studies suggested that the basis for the selective partitioning of membrane constituents may be a preference for membrane microdomains, and this hypothesis was herein tested. The partitioning of a diverse group of molecular reporters for raft and nonraft membrane subdomains was monitored during parasite invasion by time-lapse video or confocal microscopy. Unexpectedly, both raft and nonraft lipid probes, as well as both raft and nonraft cytosolic leaflet proteins, flowed unhindered past the host-parasite junction into the PVM. Moreover, neither a raft-associated type 1 transmembrane protein nor its raft-dissociated counterpart accessed the PVM, while a multispanning membrane raft protein readily did so. Considered together with previous data, these studies demonstrate that selective partitioning at the host-parasite interface is a highly complex process, in which raft association favors, but is neither necessary nor sufficient for, inclusion into the T. gondii PVM.
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Affiliation(s)
- Audra J Charron
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110, USA
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Gabel BR, Elwell C, van Ijzendoorn SCD, Engel JN. Lipid raft-mediated entry is not required for Chlamydia trachomatis infection of cultured epithelial cells. Infect Immun 2004; 72:7367-73. [PMID: 15557670 PMCID: PMC529103 DOI: 10.1128/iai.72.12.7367-7373.2004] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Using pharmacologic and biochemical criteria, we evaluated whether uptake of four different Chlamydia trachomatis serovars, D, E, K, and L2, was dependent upon lipid rafts. Our data suggest that lipid raft-mediated entry is not required for C. trachomatis infection of cultured epithelial cells.
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Affiliation(s)
- B R Gabel
- Division of Infectious Disease, Box 0654, University of California-San Francisco, San Francisco, CA 94143-0654, USA
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Boyd BL, Lee TM, Kruger EF, Pinchuk LM. Cytopathic and non-cytopathic bovine viral diarrhoea virus biotypes affect fluid phase uptake and mannose receptor-mediated endocytosis in bovine monocytes. Vet Immunol Immunopathol 2004; 102:53-65. [PMID: 15451615 DOI: 10.1016/j.vetimm.2004.06.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2004] [Revised: 05/27/2004] [Accepted: 06/11/2004] [Indexed: 10/26/2022]
Abstract
We have used non-cytopathic (ncp) and cytopathic (cp) bovine viral diarrhoea viruses (BVDV) to determine how the two biotypes affect mannose receptor (MR)-mediated endocytosis and fluid phase uptake in bovine monocytes. We have demonstrated that endocytosis in uninfected monocytes after 1 h of culture was mediated by the MR and fluid phase uptake, and after 24 h of culture it was mediated via fluid phase uptake only. Both cp and ncp BVDV affected the mechanisms of antigen uptake in monocytes. Endocytosis in BVDV infected monocytes, unlike in uninfected cells, was MR-independent and mediated by fluid phase uptake after 1 h of infection. The 24-h-BVDV infection changed the antigen uptake mechanisms to become MR- and fluid phase uptake-dependent. We conclude that antigen uptake, an important antigen presenting cell (APC) function, is affected in the early stage of BVDV infection during the first 24 h, with both BVDV biotypes, cp and ncp, having similar effects on monocyte antigen uptake in cattle. By influencing the early antigen uptake function of APC, BVDV might disrupt the function of monocytes as professional APC and contribute to the specific immunotolerance to BVDV.
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MESH Headings
- Animals
- Antigens, Viral/immunology
- Antigens, Viral/physiology
- Bovine Virus Diarrhea-Mucosal Disease/immunology
- Bovine Virus Diarrhea-Mucosal Disease/metabolism
- Bovine Virus Diarrhea-Mucosal Disease/virology
- Cattle
- Cytopathogenic Effect, Viral/immunology
- Dextrans/immunology
- Diarrhea Viruses, Bovine Viral/genetics
- Diarrhea Viruses, Bovine Viral/immunology
- Disease Reservoirs/veterinary
- Endocytosis/immunology
- Endocytosis/physiology
- Female
- Fluorescein-5-isothiocyanate/analogs & derivatives
- Lectins, C-Type/immunology
- Lectins, C-Type/metabolism
- Mannose Receptor
- Mannose-Binding Lectins/immunology
- Mannose-Binding Lectins/metabolism
- Monocytes/immunology
- Monocytes/virology
- RNA, Viral/chemistry
- RNA, Viral/genetics
- Receptors, Cell Surface/immunology
- Receptors, Cell Surface/metabolism
- Reverse Transcriptase Polymerase Chain Reaction/veterinary
- Viral Envelope Proteins/chemistry
- Viral Envelope Proteins/genetics
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Affiliation(s)
- Bobbie L Boyd
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, PO Box 6100, 39762-6100, USA
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