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Kettunen P, Koistinaho J, Rolova T. Contribution of CNS and extra-CNS infections to neurodegeneration: a narrative review. J Neuroinflammation 2024; 21:152. [PMID: 38845026 PMCID: PMC11157808 DOI: 10.1186/s12974-024-03139-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Accepted: 05/23/2024] [Indexed: 06/09/2024] Open
Abstract
Central nervous system infections have been suggested as a possible cause for neurodegenerative diseases, particularly sporadic cases. They trigger neuroinflammation which is considered integrally involved in neurodegenerative processes. In this review, we will look at data linking a variety of viral, bacterial, fungal, and protozoan infections to Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis and unspecified dementia. This narrative review aims to bring together a broad range of data currently supporting the involvement of central nervous system infections in the development of neurodegenerative diseases. The idea that no single pathogen or pathogen group is responsible for neurodegenerative diseases will be discussed. Instead, we suggest that a wide range of susceptibility factors may make individuals differentially vulnerable to different infectious pathogens and subsequent pathologies.
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Affiliation(s)
- Pinja Kettunen
- Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Jari Koistinaho
- Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland.
| | - Taisia Rolova
- Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
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2
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Pignatelli P, Curia MC, Tenore G, Bondi D, Piattelli A, Romeo U. Oral bacteriome and oral potentially malignant disorders: A systematic review of the associations. Arch Oral Biol 2024; 160:105891. [PMID: 38295615 DOI: 10.1016/j.archoralbio.2024.105891] [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: 11/29/2023] [Revised: 01/03/2024] [Accepted: 01/04/2024] [Indexed: 02/02/2024]
Abstract
INTRODUCTION Periodontal bacteria can infiltrate the epithelium, activate signaling pathways, induce inflammation, and block natural killer and cytotoxic cells, all of which contribute to the vicious circle of carcinogenesis. It is unknown whether oral dysbiosis has an impact on the etiology or prognosis of OPMD. AIMS Within this paradigm, this work systemically investigated and reported on the composition of oral microbiota in patients with oral potentially malignant disorders (OPMD) versus healthy controls. METHODS Observational studies that reported next generation sequencing analysis of oral tissue or salivary samples and found at least three bacterial species were included. Identification, screening, citation analysis, and graphical synthesis were carried out. RESULTS For oral lichen planus (OLP), the bacteria with the highest abundance were Fusobacterium, Capnocytophaga, Gemella, Granulicatella, Porphyromonas, and Rothia; for oral leukoplakia (OLK), Prevotella. Streptococci levels in OLK and OLP were lower. The usage of alcohol or smoke had no effect on the outcomes. CONCLUSIONS An increase in periodontal pathogenic bacteria could promote the development and exacerbation of lichen. Effective bacteriome-based biomarkers are worthy of further investigation and application, as are bacteriome-based treatments.
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Affiliation(s)
- Pamela Pignatelli
- COMDINAV DUE, Nave Cavour, Italian Navy, Stazione Navale Mar Grande, Viale Ionio, 74122 Taranto, Italy.
| | - Maria Cristina Curia
- Department of Medical, Oral and Biotechnological Sciences, "G. d'Annunzio" University of Chieti-Pescara, Via dei Vestini, 66100 Chieti, Italy
| | - Gianluca Tenore
- Department of Oral Sciences and Maxillofacial Surgery, Sapienza University of Rome, Via Caserta, 00161 Rome, Italy
| | - Danilo Bondi
- Department of Neuroscience, Imaging and Clinical Sciences, "G. d'Annunzio" University of Chieti-Pescara, Via dei Vestini, 66100 Chieti, Italy
| | - Adriano Piattelli
- School of Dentistry, Saint Camillus International University for Health Sciences, 00131 Rome, Italy; Facultad de Medicina, UCAM Universidad Católica San Antonio de Murcia, Guadalupe, 30107 Murcia, Spain
| | - Umberto Romeo
- Department of Oral Sciences and Maxillofacial Surgery, Sapienza University of Rome, Via Caserta, 00161 Rome, Italy
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3
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Mobarak H, Javid F, Narmi MT, Mardi N, Sadeghsoltani F, Khanicheragh P, Narimani S, Mahdipour M, Sokullu E, Valioglu F, Rahbarghazi R. Prokaryotic microvesicles Ortholog of eukaryotic extracellular vesicles in biomedical fields. Cell Commun Signal 2024; 22:80. [PMID: 38291458 PMCID: PMC10826215 DOI: 10.1186/s12964-023-01414-8] [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: 08/18/2023] [Accepted: 12/01/2023] [Indexed: 02/01/2024] Open
Abstract
Every single cell can communicate with other cells in a paracrine manner via the production of nano-sized extracellular vesicles. This phenomenon is conserved between prokaryotic and eukaryotic cells. In eukaryotic cells, exosomes (Exos) are the main inter-cellular bioshuttles with the potential to carry different signaling molecules. Likewise, bacteria can produce and release Exo-like particles, namely microvesicles (MVs) into the extracellular matrix. Bacterial MVs function with diverse biological properties and are at the center of attention due to their inherent therapeutic properties. Here, in this review article, the comparable biological properties between the eukaryotic Exos and bacterial MVs were highlighted in terms of biomedical application. Video Abstract.
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Affiliation(s)
- Halimeh Mobarak
- Department of Applied Cell Sciences, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Farzin Javid
- Department of Applied Cell Sciences, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Maryam Taghavi Narmi
- Department of Applied Cell Sciences, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Narges Mardi
- Biotechnology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Fatemeh Sadeghsoltani
- Department of Clinical Biochemistry and Laboratory Medicine, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Parisa Khanicheragh
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Samaneh Narimani
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mahdi Mahdipour
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Emel Sokullu
- Biophysics Department, Koç University School of Medicine, Rumeli Feneri, 34450, Sariyer, Istanbul, Turkey
| | - Ferzane Valioglu
- Technology Development Zones Management CO, Sakarya University, Sakarya, Turkey
| | - Reza Rahbarghazi
- Department of Applied Cell Sciences, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
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4
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Lamont RJ, Miller DP, Bagaitkar J. Illuminating the oral microbiome: cellular microbiology. FEMS Microbiol Rev 2023; 47:fuad045. [PMID: 37533213 PMCID: PMC10657920 DOI: 10.1093/femsre/fuad045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 07/11/2023] [Accepted: 08/01/2023] [Indexed: 08/04/2023] Open
Abstract
Epithelial cells line mucosal surfaces such as in the gingival crevice and provide a barrier to the ingress of colonizing microorganisms. However, epithelial cells are more than a passive barrier to microbial intrusion, and rather constitute an interactive interface with colonizing organisms which senses the composition of the microbiome and communicates this information to the underlying cells of the innate immune system. Microorganisms, for their part, have devised means to manipulate host cell signal transduction pathways to favor their colonization and survival. Study of this field, which has become known as cellular microbiology, has revealed much about epithelial cell physiology, bacterial colonization and pathogenic strategies, and innate host responses.
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Affiliation(s)
- Richard J Lamont
- Department of Oral Immunology and Infectious Diseases, University of Louisville, Louisville, KY, KY40202, United States
| | - Daniel P Miller
- Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, VA23298, United States
| | - Juhi Bagaitkar
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH, OH43205, United States
- Department of Pediatrics, The Ohio State College of Medicine, Columbus, OH, OH43210, United States
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5
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Pisani F, Pisani V, Arcangeli F, Harding A, Singhrao SK. Treponema denticola Has the Potential to Cause Neurodegeneration in the Midbrain via the Periodontal Route of Infection-Narrative Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:6049. [PMID: 37297653 PMCID: PMC10252855 DOI: 10.3390/ijerph20116049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Revised: 03/30/2023] [Accepted: 05/29/2023] [Indexed: 06/12/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease and the most common example of dementia. The neuropathological features of AD are the abnormal deposition of extracellular amyloid-β (Aβ) and intraneuronal neurofibrillary tangles with hyperphosphorylated tau protein. It is recognized that AD starts in the frontal cerebral cortex, and then it progresses to the entorhinal cortex, the hippocampus, and the rest of the brain. However, some studies on animals suggest that AD could also progress in the reverse order starting from the midbrain and then spreading to the frontal cortex. Spirochetes are neurotrophic: From a peripheral route of infection, they can reach the brain via the midbrain. Their direct and indirect effect via the interaction of their virulence factors and the microglia potentially leads to the host peripheral nerve, the midbrain (especially the locus coeruleus), and cortical damage. On this basis, this review aims to discuss the hypothesis of the ability of Treponema denticola to damage the peripheral axons in the periodontal ligament, to evade the complemental pathway and microglial immune response, to determine the cytoskeletal impairment and therefore causing the axonal transport disruption, an altered mitochondrial migration and the consequent neuronal apoptosis. Further insights about the central neurodegeneration mechanism and Treponema denticola's resistance to the immune response when aggregated in biofilm and its quorum sensing are suggested as a pathogenetic model for the advanced stages of AD.
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Affiliation(s)
- Flavio Pisani
- Faculty of Clinical and Biomedical Sciences, School of Dentistry, University of Central Lancashire, Preston PR1 2HE, UK
| | - Valerio Pisani
- IRCCS, “Santa Lucia” Foundation, Neurology and Neurorehabilitation Unit, Via Ardeatina, 306, 00179 Rome, Italy
| | - Francesca Arcangeli
- Azienda Sanitaria Locale ASLRM1, Nuovo Regina Margherita Hospital, Geriatric Department, Advanced Centre for Dementia and Cognitive Disorders, Via Emilio Morosini, 30, 00153 Rome, Italy
| | - Alice Harding
- Dementia and Neurodegenerative Disease Research Group, Faculty of Clinical and Biomedical Sciences, School of Dentistry, University of Central Lancashire, Preston PR1 2HE, UK
| | - Simarjit Kaur Singhrao
- Dementia and Neurodegenerative Disease Research Group, Faculty of Clinical and Biomedical Sciences, School of Dentistry, University of Central Lancashire, Preston PR1 2HE, UK
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6
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Rangel-Ramírez VV, González-Sánchez HM, Lucio-García C. Exosomes: from biology to immunotherapy in infectious diseases. Infect Dis (Lond) 2023; 55:79-107. [PMID: 36562253 DOI: 10.1080/23744235.2022.2149852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Exosomes are extracellular vesicles derived from the endosomal compartment, which are released by all kinds of eukaryotic and prokaryotic organisms. These vesicles contain a variety of biomolecules that differ both in quantity and type depending on the origin and cellular state. Exosomes are internalized by recipient cells, delivering their content and thus contributing to cell-cell communication in health and disease. During infections exosomes may exert a dual role, on one hand, they can transmit pathogen-related molecules mediating further infection and damage, and on the other hand, they can protect the host by activating the immune response and reducing pathogen spread. Selective packaging of pathogenic components may mediate these effects. Recently, quantitative analysis of samples by omics technologies has allowed a deep characterization of the proteins, lipids, RNA, and metabolite cargoes of exosomes. Knowledge about the content of these vesicles may facilitate their therapeutic application. Furthermore, as exosomes have been detected in almost all biological fluids, pathogenic or host-derived components can be identified in liquid biopsies, making them suitable for diagnosis and prognosis. This review attempts to organize the recent findings on exosome composition and function during viral, bacterial, fungal, and protozoan infections, and their contribution to host defense or to pathogen spread. Moreover, we summarize the current perspectives and future directions regarding the potential application of exosomes for prophylactic and therapeutic purposes.
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Affiliation(s)
| | | | - César Lucio-García
- Centro de Investigación sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, Cuernavaca, México
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7
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Pisani F, Pisani V, Arcangeli F, Harding A, Singhrao SK. Locus Coeruleus Dysfunction and Trigeminal Mesencephalic Nucleus Degeneration: A Cue for Periodontal Infection Mediated Damage in Alzheimer's Disease? INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:1007. [PMID: 36673763 PMCID: PMC9858796 DOI: 10.3390/ijerph20021007] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 12/30/2022] [Accepted: 01/01/2023] [Indexed: 06/12/2023]
Abstract
Alzheimer's disease (AD) is a leading neurodegenerative disease with deteriorating cognition as its main clinical sign. In addition to the clinical history, it is characterized by the presence of two neuropathological hallmark lesions; amyloid-beta (Aβ) and neurofibrillary tangles (NFTs), identified in the brain at post-mortem in specific anatomical areas. Recently, it was discovered that NFTs occur initially in the subcortical nuclei, such as the locus coeruleus in the pons, and are said to spread from there to the cerebral cortices and the hippocampus. This contrasts with the prior acceptance of their neuropathology in the enthorinal cortex and the hippocampus. The Braak staging system places the accumulation of phosphorylated tau (p-tau) binding to NFTs in the locus coeruleus and other subcortical nuclei to precede stages I-IV. The locus coeruleus plays diverse psychological and physiological roles within the human body including rapid eye movement sleep disorder, schizophrenia, anxiety, and depression, regulation of sleep-wake cycles, attention, memory, mood, and behavior, which correlates with AD clinical behavior. In addition, the locus coeruleus regulates cardiovascular, respiratory, and gastrointestinal activities, which have only recently been associated with AD by modern day research enabling the wider understanding of AD development via comorbidities and microbial dysbiosis. The focus of this narrative review is to explore the modes of neurodegeneration taking place in the locus coeruleus during the natural aging process of the trigeminal nerve connections from the teeth and microbial dysbiosis, and to postulate a pathogenetic mechanism due to periodontal damage and/or infection focused on Treponema denticola.
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Affiliation(s)
- Flavio Pisani
- Programme Lead, MSc/MClinDent in Clinical Periodontology, Faculty of Clinical and Biomedical Sciences, School of Dentistry, University of Central Lancashire, Preston PR1 2HE, UK
| | - Valerio Pisani
- I.R.C.C.S. “Santa Lucia” Foundation, Neurology and Neurorehabilitation Unit, Via Ardeatina, 306, 00179 Rome, Italy
| | - Francesca Arcangeli
- Azienda Sanitaria Locale ASLRM1, Nuovo Regina Margherita Hospital, Geriatric Department-Advanced Centre for Dementia and Cognitive Disorders, Via Emilio Morosini, 30, 00153 Rome, Italy
| | - Alice Harding
- Dementia and Neurodegenerative Disease Research Group, Faculty of Clinical and Biomedical Sciences, School of Dentistry, University of Central Lancashire, Preston PR1 2HE, UK
| | - Sim K. Singhrao
- Dementia and Neurodegenerative Disease Research Group, Faculty of Clinical and Biomedical Sciences, School of Dentistry, University of Central Lancashire, Preston PR1 2HE, UK
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8
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Cai R, Wang L, Zhang W, Liu B, Wu Y, Pang J, Ma C. The role of extracellular vesicles in periodontitis: pathogenesis, diagnosis, and therapy. Front Immunol 2023; 14:1151322. [PMID: 37114060 PMCID: PMC10126335 DOI: 10.3389/fimmu.2023.1151322] [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: 01/26/2023] [Accepted: 03/28/2023] [Indexed: 04/29/2023] Open
Abstract
Periodontitis is a prevalent disease and one of the leading causes of tooth loss. Biofilms are initiating factor of periodontitis, which can destroy periodontal tissue by producing virulence factors. The overactivated host immune response is the primary cause of periodontitis. The clinical examination of periodontal tissues and the patient's medical history are the mainstays of periodontitis diagnosis. However, there is a lack of molecular biomarkers that can be used to identify and predict periodontitis activity precisely. Non-surgical and surgical treatments are currently available for periodontitis, although both have drawbacks. In clinical practice, achieving the ideal therapeutic effect remains a challenge. Studies have revealed that bacteria produce extracellular vesicles (EVs) to export virulence proteins to host cells. Meanwhile, periodontal tissue cells and immune cells produce EVs that have pro- or anti-inflammatory effects. Accordingly, EVs play a critical role in the pathogenesis of periodontitis. Recent studies have also presented that the content and composition of EVs in saliva and gingival crevicular fluid (GCF) can serve as possible periodontitis diagnostic indicators. In addition, studies have indicated that stem cell EVs may encourage periodontal regeneration. In this article, we mainly review the role of EVs in the pathogenesis of periodontitis and discuss their diagnostic and therapeutic potential.
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Affiliation(s)
- Rong Cai
- Department of Stomatology, Air Force Medical Center, The Fourth Military Medical University, Beijing, China
| | - Lu Wang
- Department of Critical Care Medicine, The First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Wei Zhang
- Department of Stomatology, Air Force Medical Center, The Fourth Military Medical University, Beijing, China
| | - Bing Liu
- Department of Stomatology, Air Force Medical Center, The Fourth Military Medical University, Beijing, China
| | - Yiqi Wu
- Department of Critical Care Medicine, The First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Jianliang Pang
- Department of Stomatology, Air Force Medical Center, The Fourth Military Medical University, Beijing, China
- *Correspondence: Chufan Ma, ; Jianliang Pang,
| | - Chufan Ma
- Department of Stomatology, Air Force Medical Center, The Fourth Military Medical University, Beijing, China
- *Correspondence: Chufan Ma, ; Jianliang Pang,
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9
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Desulfovibrio fairfieldensis-Derived Outer Membrane Vesicles Damage Epithelial Barrier and Induce Inflammation and Pyroptosis in Macrophages. Cells 2022; 12:cells12010089. [PMID: 36611884 PMCID: PMC9818291 DOI: 10.3390/cells12010089] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 12/21/2022] [Accepted: 12/22/2022] [Indexed: 12/28/2022] Open
Abstract
Sulfate-reducing bacteria Desulfovibrio fairfieldensis is an opportunistic pathogen that widely exists in the human intestine and can cause severe infectious diseases. However, the mechanisms contributing to its pathogenesis remain of great interest. In this study, we aim to investigate the outer membrane vesicles (OMVs) secreted by D. fairfieldensis and their pathogenic effect. The OMVs separated by ultracentrifugation were spherical and displayed a characteristic bilayer lipid structure observed by transmission electron microscopy, with an average hydrodynamic diameter of 75 nm measurement using the particle size analyzer. We identified 1496 and 916 proteins from D. fairfieldensis and its OMVs using label-free non-target quantitative proteomics, respectively. The 560 co-expressed proteins could participate in bacterial life activities by function prediction. The translocation protein TolB, which participates in OMVs biogenesis and transporting toxins was highly expressed in OMVs. The OMVs inhibited the expression of tight junction proteins OCCLUDIN and ZO-1 in human colonic epithelial cells (Caco-2). The OMVs decreased the cell viability of monocyte macrophages (THP-1-Mφ) and activated various inflammatory factors secretion, including interferon-γ (IFN-γ), tumor necrosis factor (TNF-α), and many interleukins. Further, we found the OMVs induced the expression of cleaved-gasdermin D, caspase-1, and c-IL-1β and caused pyroptosis in THP-1-Mφ cells. Taken together, these data reveal that the D. fairfieldensis OMVs can damage the intestinal epithelial barrier and activate intrinsic inflammation.
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Abstract
This review focuses on nonlytic outer membrane vesicles (OMVs), a subtype of bacterial extracellular vesicles (BEVs) produced by Gram-negative organisms focusing on the mechanisms of their biogenesis, cargo, and function. Throughout, we highlight issues concerning the characterization of OMVs and distinguishing them from other types of BEVs. We also highlight the shortcomings of commonly used methodologies for the study of BEVs that impact the interpretation of their functionality and suggest solutions to standardize protocols for OMV studies.
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Affiliation(s)
| | - Simon R. Carding
- Quadram Institute Bioscience, Norwich, United Kingdom
- Norwich Medical School, University of East Anglia, Norwich, United Kingdom
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11
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Hosseini-Giv N, Basas A, Hicks C, El-Omar E, El-Assaad F, Hosseini-Beheshti E. Bacterial extracellular vesicles and their novel therapeutic applications in health and cancer. Front Cell Infect Microbiol 2022; 12:962216. [PMID: 36439225 PMCID: PMC9691856 DOI: 10.3389/fcimb.2022.962216] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 10/20/2022] [Indexed: 10/03/2023] Open
Abstract
Bacterial cells communicate with host cells and other bacteria through the release of membrane vesicles known as bacterial extracellular vesicles (BEV). BEV are established mediators of intracellular signaling, stress tolerance, horizontal gene transfer, immune stimulation and pathogenicity. Both Gram-positive and Gram-negative bacteria produce extracellular vesicles through different mechanisms based on cell structure. BEV contain and transfer different types of cargo such as nucleic acids, proteins and lipids, which are used to interact with and affect host cells such as cytotoxicity and immunomodulation. The role of these membranous microvesicles in host communication, intra- and inter-species cell interaction and signaling, and contribution to various diseases have been well demonstrated. Due to their structure, these vesicles can be easily engineered to be utilized for clinical application, as shown with its role in vaccine therapy, and could be used as a diagnostic and cancer drug delivery tool in the future. However, like other novel therapeutic approaches, further investigation and standardization is imperative for BEV to become a routine vector or a conventional treatment method.
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Affiliation(s)
- Niloufar Hosseini-Giv
- Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Alyza Basas
- UNSW Microbiome Research Centre, St George and Sutherland Clinical Campuses, School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
| | - Chloe Hicks
- UNSW Microbiome Research Centre, St George and Sutherland Clinical Campuses, School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
| | - Emad El-Omar
- UNSW Microbiome Research Centre, St George and Sutherland Clinical Campuses, School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
| | - Fatima El-Assaad
- UNSW Microbiome Research Centre, St George and Sutherland Clinical Campuses, School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
| | - Elham Hosseini-Beheshti
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Camperdown, NSW, Australia
- The Sydney Nano Institute, The University of Sydney, Sydney, NSW, Australia
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12
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Suri K, D'Souza A, Huang D, Bhavsar A, Amiji M. Bacterial extracellular vesicle applications in cancer immunotherapy. Bioact Mater 2022; 22:551-566. [PMID: 36382022 PMCID: PMC9637733 DOI: 10.1016/j.bioactmat.2022.10.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 10/10/2022] [Accepted: 10/22/2022] [Indexed: 12/03/2022] Open
Abstract
Cancer therapy is undergoing a paradigm shift toward immunotherapy focusing on various approaches to activate the host immune system. As research to identify appropriate immune cells and activate anti-tumor immunity continues to expand, scientists are looking at microbial sources given their inherent ability to elicit an immune response. Bacterial extracellular vesicles (BEVs) are actively studied to control systemic humoral and cellular immune responses instead of using whole microorganisms or other types of extracellular vesicles (EVs). BEVs also provide the opportunity as versatile drug delivery carriers. Unlike mammalian EVs, BEVs have already made it to the clinic with the meningococcal vaccine (Bexsero®). However, there are still many unanswered questions in the use of BEVs, especially for chronic systemically administered immunotherapies. In this review, we address the opportunities and challenges in the use of BEVs for cancer immunotherapy and provide an outlook towards development of BEV products that can ultimately translate to the clinic.
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Affiliation(s)
- Kanika Suri
- Department of Bioengineering, College of Engineering, Northeastern University, Boston, MA, 02115, USA
| | - Anisha D'Souza
- Department of Pharmaceutical Sciences, School of Pharmacy, Northeastern University, Boston, MA, 02115, USA,Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, 20115, USA
| | - Di Huang
- Department of Pharmaceutical Sciences, School of Pharmacy, Northeastern University, Boston, MA, 02115, USA,Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, 20115, USA
| | - Aashray Bhavsar
- Department of Pharmaceutical Sciences, School of Pharmacy, Northeastern University, Boston, MA, 02115, USA
| | - Mansoor Amiji
- Department of Pharmaceutical Sciences, School of Pharmacy, Northeastern University, Boston, MA, 02115, USA,Department of Chemical Engineering, College of Engineering, Northeastern University, Boston, MA, 02115, USA,Corresponding author. Department of Pharmaceutical Sciences, School of Pharmacy, Northeastern University, Boston, MA, 02115, USA.
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13
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Michel LV, Gaborski T. Outer Membrane Vesicles as Molecular Biomarkers for Gram-negative Sepsis: Taking Advantage of Nature's Perfect Packages. J Biol Chem 2022; 298:102483. [PMID: 36108741 PMCID: PMC9576880 DOI: 10.1016/j.jbc.2022.102483] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 07/13/2022] [Accepted: 09/08/2022] [Indexed: 11/18/2022] Open
Abstract
Sepsis is an often life-threatening response to infection, occurring when host pro-inflammatory immune responses become abnormally elevated and dysregulated. To diagnose sepsis, the patient must have a confirmed or predicted infection, as well as other symptoms associated with the pathophysiology of sepsis. However, a recent study found that a specific causal organism could not be determined in the majority (70.1%) of sepsis cases, likely due to aggressive antibiotics or localized infections. The timing of a patient's sepsis diagnosis is often predictive of their clinical outcome, underlining the need for a more definitive molecular diagnostic test. Here, we outline the advantages and challenges to using bacterial outer membrane vesicles (OMVs), nanoscale spherical buds derived from the outer membrane of Gram-negative bacteria, as a diagnostic biomarker for Gram-negative sepsis. Advantages include OMV abundance, their robustness in the presence of antibiotics, and their unique features derived from their parent cell that could allow for differentiation between bacterial species. Challenges include the rigorous purification methods required to isolate OMVs from complex biofluids and the additional need to separate OMVs from similarly-sized extracellular vesicles, which can share physical properties with OMVs.
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Affiliation(s)
- Lea Vacca Michel
- School of Chemistry and Materials Science, Rochester Institute of Technology, Rochester, New York, USA.
| | - Thomas Gaborski
- Department of Biomedical Engineering, Rochester Institute of Technology, Rochester, New York, USA
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14
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Blancá B, Hayes JA, Surmann K, Hugo V, Hentschker C, Lamberti Y, Völker U, Rodriguez ME. Bordetella pertussis outer membrane vesicles as virulence factor vehicles that influence bacterial interaction with macrophages. Pathog Dis 2022; 80:6655986. [PMID: 35927587 DOI: 10.1093/femspd/ftac031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 07/28/2022] [Accepted: 08/01/2022] [Indexed: 01/18/2023] Open
Abstract
Gram-negative pathogenic bacteria constitutively shed outer membrane vesicles (OMVs) which play a significant role in the host-pathogen interaction, eventually determining the outcome of the infection. We previously found that Bordetella pertussis, the etiological agent of whooping cough, survives the innate interaction with human macrophages remaining alive inside these immune cells. Adenylate cyclase (CyaA), one of the main toxins of this pathogen, was found involved in the modulation of the macrophage defense response, eventually promoting bacterial survival within the cells. We here investigated whether B. pertussis OMVs, loaded with most of the bacterial toxins and CyaA among them, modulate the macrophage response to the bacterial infection. We observed that the pre-incubation of macrophages with OMVs led to a decreased macrophage defense response to the encounter with the bacteria, in a CyaA dependent way. Our results suggest that CyaA delivered by B. pertussis OMVs dampens macrophages protective function by decreasing phagocytosis and the bactericidal capability of these host cells. By increasing the chances of bacterial survival to the innate encounter with the macrophages, B. pertussis OMVs might play a relevant role in the course of infection, promoting bacterial persistence within the host and eventually, shaping the whole infection process.
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Affiliation(s)
- Bruno Blancá
- CINDEFI (UNLP CONICET La Plata), School of Sciences, La Plata National University, La Plata, Argentina
| | - Jimena Alvarez Hayes
- CINDEFI (UNLP CONICET La Plata), School of Sciences, La Plata National University, La Plata, Argentina
| | - Kristin Surmann
- Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - Valdez Hugo
- CINDEFI (UNLP CONICET La Plata), School of Sciences, La Plata National University, La Plata, Argentina
| | - Christian Hentschker
- Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - Yanina Lamberti
- CINDEFI (UNLP CONICET La Plata), School of Sciences, La Plata National University, La Plata, Argentina
| | - Uwe Völker
- Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - María Eugenia Rodriguez
- CINDEFI (UNLP CONICET La Plata), School of Sciences, La Plata National University, La Plata, Argentina
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15
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Radaic A, Malone E, Kamarajan P, Kapila YL. Solid Lipid Nanoparticles Loaded with Nisin (SLN-Nisin) are More Effective Than Free Nisin as Antimicrobial, Antibiofilm, and Anticancer Agents. J Biomed Nanotechnol 2022; 18:1227-1235. [PMID: 35854440 PMCID: PMC9741812 DOI: 10.1166/jbn.2022.3314] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Bacteriocins are peptides produced by bacteria to inhibit the growth of other prokaryotes. Nisin is a bacteriocin widely used in the food industry and for biomedical applications. However, bacteriocins have some limitations, as they experience mechanisms of resistance, degradation by proteases, and suboptimal intracellular delivery. Combining bacteriocins with nanoscale drug delivery systems (nano-DDS) is an approach that can help overcome these limitations. Among the nano-DDS, solid lipid nanoparticles (SLN) have been described as promising candidates, because of their potential for industrial scale-up and lower toxicity. The objective of this proof-of-concept study was to investigate the use of nisin-loaded SLN (SLN-Nisin) as an antimicrobial and anticancer therapeutic. We show that SLN-Nisin can significantly inhibit the growth of the oral pathogen, Treponema denticola, disrupt oral biofilms, and decrease oral squamous cell carcinoma cell (OSCC) viability compared to free nisin. Further, analysis with scanning electron microscopy (SEM) revealed significant morphological changes in OSCC cells challenged with SLN-Nisin, compared to the empty-nanoparticle or free nisin, indicating that SLN-Nisin likely decreases cell viability by increasing pore formation. This data reveals that nano-DDS are robust tools that can enhance bacteriocin properties.
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Affiliation(s)
- Allan Radaic
- Department of Orofacial Sciences, School of Dentistry, University of California, San Francisco (UCSF), San Francisco, 94143, CA, USA
| | - Erin Malone
- Department of Orofacial Sciences, School of Dentistry, University of California, San Francisco (UCSF), San Francisco, 94143, CA, USA
| | - Pachiyappan Kamarajan
- Department of Orofacial Sciences, School of Dentistry, University of California, San Francisco (UCSF), San Francisco, 94143, CA, USA
| | - Yvonne L. Kapila
- Division of Oral and Systemic Health Sciences in the Sections of Biosystems and Function and the Division of Regenerative and Reconstructive Sciences in the Section of Periodontics, University of California, Los Angeles (UCLA) School of Dentistry, 10833 Le Conte Ave., Box 951668, Mail Office 53-039, Los Angeles, CA 90095-1668, USA,Author to whom correspondence should be addressed.
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16
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Mirmohammadsadegh N, Mashreghi N, Amin M. Potential Treponema denticola-based periodontal vaccine to resolve a global public health challenge: a narrative literature review. Expert Rev Vaccines 2022; 21:621-632. [PMID: 35195497 DOI: 10.1080/14760584.2022.2044798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Periodontitis is a diseased condition of the gum which imposes considerable costs on healthcare systems. It progresses further beyond the inflammation of supportive tissues of the teeth, and the collateral damages are closely associated with Alzheimer's disease, cardiovascular disease, and diabetes mellitus. AREAS COVERED A comprehensive literature review was performed to summarize published studies in English during the period of 1990-2021 to discuss the rationales for developing periodontal vaccine, cost-effectiveness analyses on the prevention of periodontitis, Treponema denticola-based vaccine candidates, as well as immunological mechanisms in animal models. EXPERT OPINION Preventive strategies against periodontitis may halt the onset of gum inflammation itself and the consequent chronic diseases. Considering the multi-microbial condition of periodontitis, an ideal periodontal vaccine should target multiple pathological pathways. Preventive approaches compared to surgical treatments evidently have significant impact on the healthcare budget and long-term health of the individuals in different communities. Despite many advances in periodontal vaccine research, there are still significant hurdles to overcome in developing a vaccine. Investment in research and development activities on key periodontal pathogens including Treponema denticola and Porphyromonas gingivalis in the foreseeable future is a worthy and cost-effective approach for the policymakers to prevent deleterious impacts of periodontitis.
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Affiliation(s)
- Navid Mirmohammadsadegh
- Department of Drug and Food Control, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.,Pharmaceutical Microbiology Group, The Institute of Pharmaceutical Sciences (TIPS), Tehran University of Medical Sciences, Tehran, Iran
| | - Neshaut Mashreghi
- Department of Drug and Food Control, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.,Pharmaceutical Microbiology Group, The Institute of Pharmaceutical Sciences (TIPS), Tehran University of Medical Sciences, Tehran, Iran
| | - Mohsen Amin
- Department of Drug and Food Control, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.,Pharmaceutical Microbiology Group, The Institute of Pharmaceutical Sciences (TIPS), Tehran University of Medical Sciences, Tehran, Iran
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17
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McVey MJ, Maishan M, Foley A, Turki R, Roach EJ, Deschler R, Weidenfeld S, Goldenberg NM, Khursigara CM, Kuebler WM. Pseudomonas aeruginosa membrane vesicles cause endothelial barrier failure and lung injury. Eur Respir J 2022; 59:13993003.01500-2021. [PMID: 35169027 DOI: 10.1183/13993003.01500-2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 02/04/2022] [Indexed: 11/05/2022]
Affiliation(s)
- Mark J McVey
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada.,Departments of Anesthesiology and Pain Medicine and Physiology, University of Toronto, Toronto, ON, Canada.,Department of Anesthesia and Pain Medicine, Hospital for Sick Children, Toronto, ON, Canada.,Department of Physics, Ryerson University, Toronto, ON, Canada
| | - Mazharul Maishan
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - Anna Foley
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Razan Turki
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada.,Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Elyse J Roach
- Department of Molecular and Cellular Biology, Guelph University, Guelph, ON, Canada
| | - Rose Deschler
- Institute of Physiology, Charité-Universitätsmedizin, Berlin, Germany
| | - Sarah Weidenfeld
- Institute of Physiology, Charité-Universitätsmedizin, Berlin, Germany
| | - Neil M Goldenberg
- Departments of Anesthesiology and Pain Medicine and Physiology, University of Toronto, Toronto, ON, Canada.,Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Cezar M Khursigara
- Department of Molecular and Cellular Biology, Guelph University, Guelph, ON, Canada
| | - Wolfgang M Kuebler
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada .,Department of Physiology, University of Toronto, Toronto, ON, Canada.,Institute of Physiology, Charité-Universitätsmedizin, Berlin, Germany.,Department of Surgery, University of Toronto, Toronto, ON, Canada
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18
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Liposome-Polymer Complex for Drug Delivery System and Vaccine Stabilization. Heliyon 2022; 8:e08934. [PMID: 35243059 PMCID: PMC8861389 DOI: 10.1016/j.heliyon.2022.e08934] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 01/25/2022] [Accepted: 02/08/2022] [Indexed: 12/18/2022] Open
Abstract
Liposomes have been used extensively as micro- and nanocarriers for hydrophobic or hydrophilic molecules. However, conventional liposomes are biodegradable and quickly eliminated, making it difficult to be used for delivery in specific routes, such as the oral and systemic routes. One way to overcome this problem is through complexation with polymers, which is referred to as a liposome complex. The use of polymers can increase the stability of liposome with regard to pH, chemicals, enzymes, and the immune system. In some cases, specific polymers can condition the properties of liposomes to be explicitly used in drug delivery, such as targeted delivery and controlled release. These properties are influenced by the type of polymer, crosslinker, interaction, and bond in the complexation process. Therefore, it is crucial to study and review these parameters for the development of more optimal forms and properties of the liposome complex. This article discusses the use of natural and synthetic polymers, ways of interaction between polymers and liposomes (on the surface, incorporation in lamellar chains, and within liposomes), types of bonds, evaluation standards, and their effects on the stability and pharmacokinetic profile of the liposome complex, drugs, and vaccines. This article concludes that both natural and synthetic polymers can be used in modifying the structure and physicochemical properties of liposomes to specify their use in targeted delivery, controlled release, and stabilizing drugs and vaccines.
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19
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Kokubu E, Kikuchi Y, Okamoto-Shibayama K, Ishihara K. Effect of Treponema Denticola Infection on Epithelial Cells. THE BULLETIN OF TOKYO DENTAL COLLEGE 2022; 63:13-22. [DOI: 10.2209/tdcpublication.2021-0037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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20
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Radaic A, Ganther S, Kamarajan P, Grandis J, Yom SS, Kapila YL. Paradigm shift in the pathogenesis and treatment of oral cancer and other cancers focused on the oralome and antimicrobial-based therapeutics. Periodontol 2000 2021; 87:76-93. [PMID: 34463982 PMCID: PMC8415008 DOI: 10.1111/prd.12388] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The oral microbiome is a community of microorganisms, comprised of bacteria, fungi, viruses, archaea, and protozoa, that form a complex ecosystem within the oral cavity. Although minor perturbations in the environment are frequent and compensable, major shifts in the oral microbiome can promote an unbalanced state, known as dysbiosis. Dysbiosis can promote oral diseases, including periodontitis. In addition, oral dysbiosis has been associated with other systemic diseases, including cancer. The objective of this review is to evaluate the epidemiologic evidence linking periodontitis to oral, gastrointestinal, lung, breast, prostate, and uterine cancers, as well as describe new evidence and insights into the role of oral dysbiosis in the etiology and pathogenesis of the cancer types discussed. Finally, we discuss how antimicrobials, antimicrobial peptides, and probiotics may be promising tools to prevent and treat these cancers, targeting both the microbes and associated carcinogenesis processes. These findings represent a novel paradigm in the pathogenesis and treatment of cancer focused on the oral microbiome and antimicrobial‐based therapies.
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Affiliation(s)
- Allan Radaic
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, California, USA
| | - Sean Ganther
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, California, USA
| | - Pachiyappan Kamarajan
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, California, USA
| | - Jennifer Grandis
- Department of Otolaryngology-Head and Neck Surgery, University of California San Francisco, San Francisco, California, USA
| | - Sue S Yom
- Department of Radiation Oncology, University of California San Francisco, San Francisco, California, USA
| | - Yvonne L Kapila
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, California, USA
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21
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Sheikh A, Taube J, Greathouse KL. Contribution of the Microbiota and their Secretory Products to Inflammation and Colorectal Cancer Pathogenesis: The Role of Toll-like Receptors. Carcinogenesis 2021; 42:1133-1142. [PMID: 34218275 DOI: 10.1093/carcin/bgab060] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 06/08/2021] [Accepted: 07/02/2021] [Indexed: 12/13/2022] Open
Abstract
Alterations in diversity and function of the gut microbiome are associated with concomitant changes in immune response, including chronic inflammation. Chronic inflammation is a major risk factor for colorectal cancer (CRC). An important component of the inflammatory response system are the toll-like receptors (TLRs). TLRs are capable of sensing microbial components, including nucleic acids, lipopolysaccharides, and peptidoglycans, as well as bacterial outer membrane vesicles (OMV). OMVs can be decorated with or carry as cargo these TLR activating factors. These microbial factors can either promote tolerance or activate signaling pathways leading to chronic inflammation. Herein we discuss the role of the microbiome and the OMVs that originate from intestinal bacteria in promoting chronic inflammation and the development of colitis-associated CRC. We also discuss the contribution of TLRs in mediating the microbiome-inflammation axis and subsequent cancer development. Understanding the role of the microbiome and its secretory factors in TLR response may lead to the development of better cancer therapeutics.
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Affiliation(s)
- Aadil Sheikh
- Department of Biology, College of Arts and Sciences, Baylor University
| | - Joseph Taube
- Department of Biology, College of Arts and Sciences, Baylor University
| | - K Leigh Greathouse
- Department of Biology, College of Arts and Sciences, Baylor University.,Human Science and Design, Robbins College of Health and Human Sciences, Baylor University
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22
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Ganther S, Radaic A, Malone E, Kamarajan P, Chang NYN, Tafolla C, Zhan L, Fenno JC, Kapila YL. Treponema denticola dentilisin triggered TLR2/MyD88 activation upregulates a tissue destructive program involving MMPs via Sp1 in human oral cells. PLoS Pathog 2021; 17:e1009311. [PMID: 34255809 PMCID: PMC8301614 DOI: 10.1371/journal.ppat.1009311] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 07/23/2021] [Accepted: 05/26/2021] [Indexed: 12/28/2022] Open
Abstract
Periodontal disease is driven by dysbiosis in the oral microbiome, resulting in over-representation of species that induce the release of pro-inflammatory cytokines, chemokines, and tissue-remodeling matrix metalloproteinases (MMPs) in the periodontium. These chronic tissue-destructive inflammatory responses result in gradual loss of tooth-supporting alveolar bone. The oral spirochete Treponema denticola, is consistently found at significantly elevated levels in periodontal lesions. Host-expressed Toll-Like Receptor 2 (TLR2) senses a variety of bacterial ligands, including acylated lipopolysaccharides and lipoproteins. T. denticola dentilisin, a surface-expressed protease complex comprised of three lipoproteins has been implicated as a virulence factor in periodontal disease, primarily due to its proteolytic activity. While the role of acylated bacterial components in induction of inflammation is well-studied, little attention has been given to the potential role of the acylated nature of dentilisin. The purpose of this study was to test the hypothesis that T. denticola dentilisin activates a TLR2-dependent mechanism, leading to upregulation of tissue-destructive genes in periodontal tissue. RNA-sequencing of periodontal ligament cells challenged with T. denticola bacteria revealed significant upregulation of genes associated with extracellular matrix organization and degradation including potentially tissue-specific inducible MMPs that may play novel roles in modulating host immune responses that have yet to be characterized within the context of oral disease. The Gram-negative oral commensal, Veillonella parvula, failed to upregulate these same MMPs. Dentilisin-induced upregulation of MMPs was mediated via TLR2 and MyD88 activation, since knockdown of expression of either abrogated these effects. Challenge with purified dentilisin upregulated the same MMPs while a dentilisin-deficient T. denticola mutant had no effect. Finally, T. denticola-mediated activation of TLR2/MyD88 lead to the nuclear translocation of the transcription factor Sp1, which was shown to be a critical regulator of all T. denticola-dependent MMP expression. Taken together, these data suggest that T. denticola dentilisin stimulates tissue-destructive cellular processes in a TLR2/MyD88/Sp1-dependent fashion.
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Affiliation(s)
- Sean Ganther
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, California, United States of America
| | - Allan Radaic
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, California, United States of America
| | - Erin Malone
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, California, United States of America
| | - Pachiyappan Kamarajan
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, California, United States of America
| | - Nai-Yuan Nicholas Chang
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, California, United States of America
| | - Christian Tafolla
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, California, United States of America
| | - Ling Zhan
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, California, United States of America
| | - J. Christopher Fenno
- Department of Biological and Material Sciences & Prosthodontics, School of Dentistry, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Yvonne L. Kapila
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, California, United States of America
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23
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Dell’Annunziata F, Folliero V, Giugliano R, De Filippis A, Santarcangelo C, Izzo V, Daglia M, Galdiero M, Arciola CR, Franci G. Gene Transfer Potential of Outer Membrane Vesicles of Gram-Negative Bacteria. Int J Mol Sci 2021; 22:ijms22115985. [PMID: 34205995 PMCID: PMC8198371 DOI: 10.3390/ijms22115985] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 05/28/2021] [Accepted: 05/31/2021] [Indexed: 12/11/2022] Open
Abstract
The increasing spread of multidrug-resistant pathogenic bacteria is one of the major threats to public health worldwide. Bacteria can acquire antibiotic resistance and virulence genes through horizontal gene transfer (HGT). A novel horizontal gene transfer mechanism mediated by outer membrane vesicles (OMVs) has been recently identified. OMVs are rounded nanostructures released during their growth by Gram-negative bacteria. Biologically active toxins and virulence factors are often entrapped within these vesicles that behave as molecular carriers. Recently, OMVs have been reported to contain DNA molecules, but little is known about the vesicle packaging, release, and transfer mechanisms. The present review highlights the role of OMVs in HGT processes in Gram-negative bacteria.
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Affiliation(s)
- Federica Dell’Annunziata
- Department of Experimental Medicine, University of Campania Luigi Vanvitelli, 80138 Naples, Italy; (F.D.); (V.F.); (R.G.); (A.D.F.); (M.G.)
| | - Veronica Folliero
- Department of Experimental Medicine, University of Campania Luigi Vanvitelli, 80138 Naples, Italy; (F.D.); (V.F.); (R.G.); (A.D.F.); (M.G.)
| | - Rosa Giugliano
- Department of Experimental Medicine, University of Campania Luigi Vanvitelli, 80138 Naples, Italy; (F.D.); (V.F.); (R.G.); (A.D.F.); (M.G.)
| | - Anna De Filippis
- Department of Experimental Medicine, University of Campania Luigi Vanvitelli, 80138 Naples, Italy; (F.D.); (V.F.); (R.G.); (A.D.F.); (M.G.)
| | - Cristina Santarcangelo
- Department of Pharmacy, University of Naples Federico II, via Domenico Montesano 49, 80131 Naples, Italy; (C.S.); (M.D.)
| | - Viviana Izzo
- Department of Medicine, Surgery and Dentistry Scuola Medica Salernitana, University of Salerno, 84081 Salerno, Italy;
| | - Maria Daglia
- Department of Pharmacy, University of Naples Federico II, via Domenico Montesano 49, 80131 Naples, Italy; (C.S.); (M.D.)
- International Research Center for Food Nutrition and Safety, Jiangsu University, Zhenjiang 212013, China
| | - Massimiliano Galdiero
- Department of Experimental Medicine, University of Campania Luigi Vanvitelli, 80138 Naples, Italy; (F.D.); (V.F.); (R.G.); (A.D.F.); (M.G.)
| | - Carla Renata Arciola
- Research Unit on Implant Infections, Laboratorio di Patologia delle Infezioni Associate all’Impianto, IRCCS Istituto Ortopedico Rizzoli, 40136 Bologna, Italy
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, 40126 Bologna, Italy
- Correspondence: (C.R.A.); (G.F.)
| | - Gianluigi Franci
- Department of Medicine, Surgery and Dentistry Scuola Medica Salernitana, University of Salerno, 84081 Salerno, Italy;
- Correspondence: (C.R.A.); (G.F.)
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24
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Mehanny M, Lehr CM, Fuhrmann G. Extracellular vesicles as antigen carriers for novel vaccination avenues. Adv Drug Deliv Rev 2021; 173:164-180. [PMID: 33775707 DOI: 10.1016/j.addr.2021.03.016] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 03/01/2021] [Accepted: 03/23/2021] [Indexed: 02/07/2023]
Abstract
Antigen delivery has always been a challenge in scientific practice of vaccine formulation. Yet, mammalian extracellular vesicles (EVs) or bacterial membrane vesicles (MVs) provide an innovative avenue for safe and effective delivery of antigenic material. They include intrinsically loaded antigens from EV-secreting cells or extrinsically loaded antigens onto pre-formed vesicles. Interestingly, many studies shed light on potential novel anti-cancer vaccination immunotherapy for therapeutic applications from mammalian cell host-derived EVs, as well as conventional vaccination for prophylactic applications using bacterial cell-derived MVs against infectious diseases. Here, we discuss the rationale, status quo and potential for both vaccine applications using EVs.
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25
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Goetting-Minesky MP, Godovikova V, Fenno JC. Approaches to Understanding Mechanisms of Dentilisin Protease Complex Expression in Treponema denticola. Front Cell Infect Microbiol 2021; 11:668287. [PMID: 34084756 PMCID: PMC8167434 DOI: 10.3389/fcimb.2021.668287] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 05/04/2021] [Indexed: 11/25/2022] Open
Abstract
The oral spirochete Treponema denticola is a keystone periodontal pathogen that, in association with members of a complex polymicrobial oral biofilm, contributes to tissue damage and alveolar bone loss in periodontal disease. Virulence-associated behaviors attributed to T. denticola include disruption of the host cell extracellular matrix, tissue penetration and disruption of host cell membranes accompanied by dysregulation of host immunoregulatory factors. T. denticola dentilisin is associated with several of these behaviors. Dentilisin is an outer membrane-associated complex of acylated subtilisin-family PrtP protease and two other lipoproteins, PrcB and PrcA, that are unique to oral spirochetes. Dentilisin is encoded in a single operon consisting of prcB-prcA-prtP. We employ multiple approaches to study mechanisms of dentilisin assembly and PrtP protease activity. To determine the role of each protein in the protease complex, we have made targeted mutations throughout the protease locus, including polar and nonpolar mutations in each gene (prcB, prcA, prtP) and deletions of specific PrtP domains, including single base mutagenesis of key PrtP residues. These will facilitate distinguishing between host cell responses to dentilisin protease activity and its acyl groups. The boundaries of the divergent promoter region and the relationship between dentilisin and the adjacent iron transport operon are being resolved by incremental deletions in the sequence immediately 5’ to the protease locus. Comparison of the predicted three-dimensional structure of PrtP to that of other subtilisin-like proteases shows a unique PrtP C-terminal domain of approximately 250 residues. A survey of global gene expression in the presence or absence of protease gene expression reveals potential links between dentilisin and iron uptake and homeostasis in T. denticola. Understanding the mechanisms of dentilisin transport, assembly and activity of this unique protease complex may lead to more effective prophylactic or therapeutic treatments for periodontal disease.
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Affiliation(s)
- M Paula Goetting-Minesky
- Department of Biologic and Materials Sciences & Prosthodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, United States
| | - Valentina Godovikova
- Department of Biologic and Materials Sciences & Prosthodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, United States
| | - J Christopher Fenno
- Department of Biologic and Materials Sciences & Prosthodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, United States
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26
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Khemgaew R, Omachi M, Takesada T, Vetchapitak T, Sato H, Taniguchi T, Misawa N. Transcellular penetration of Treponema phagedenis isolated from papillomatous digital dermatitis in polarized normal human epidermal keratinocytes in vitro. J Vet Med Sci 2021; 83:889-897. [PMID: 33853987 PMCID: PMC8267188 DOI: 10.1292/jvms.21-0034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Papillomatous digital dermatitis (PDD) is a polymicrobial infection causing lameness in
dairy cattle. Culture-independent analysis has shown that Treponema
phagedenis is present consistently and predominantly in the lesions. However,
the pathogenesis of PDD, especially the tissue penetration pathway, has not been examined.
In the present study, we investigated whether T. phagedenis strains
isolated from PDD produce proteolytic enzyme (s) for disruption of the epithelial cell
barrier and have the ability to translocate in polarized normal human epidermal
keratinocytes (NHEK) in vitro. Ten strains of T.
phagedenis isolated from lesions did not show proteolytic activity on modified
skim milk agar, although a human strain of T. denticola used as a control
showed such activity. The integrity of tight junctions was monitored by measurement of
transepithelial electrical resistance (TER). The TER values after inoculation of the
T. phagedenis strains examined did not change during the experimental
period; however, apical to basolateral translocation of T. phagedenis was
confirmed after 24 hr by microscopy and Treponema-specific PCR. We
further confirmed that translocation of T. phagedenis was accelerated by
co-inoculation with live T. denticola, but not with heat-killed
organisms. Furthermore, tight junction ZO-1 protein was not lost intensity after
inoculation with T. phagedenis and the organism was observed in NHEK
cells using a florescence microscope. These results suggest that T.
phagedenis strains may translocate via a transcellular route in
vitro and that the invasion is accelerated by other bacteria, such as
T. denticola, producing proteolytic activity.
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Affiliation(s)
- Rathanon Khemgaew
- Graduate School of Medicine and Veterinary Medicine, University of Miyazaki, 5200 Kihara-Kiyotakecho, Miyazaki 889-1692, Japan.,Laboratory of Veterinary Public Health, Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan
| | - Mari Omachi
- Laboratory of Veterinary Public Health, Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan
| | - Tomoe Takesada
- Laboratory of Veterinary Public Health, Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan
| | - Torrung Vetchapitak
- Center for Animal Disease Control, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan
| | - Hiroyuki Sato
- Laboratory of Veterinary Clinical Radiology, Department of Veterinary Medical Science, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan
| | - Takako Taniguchi
- Center for Animal Disease Control, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan
| | - Naoaki Misawa
- Graduate School of Medicine and Veterinary Medicine, University of Miyazaki, 5200 Kihara-Kiyotakecho, Miyazaki 889-1692, Japan.,Laboratory of Veterinary Public Health, Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan.,Center for Animal Disease Control, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan
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27
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Bitto NJ, Cheng L, Johnston EL, Pathirana R, Phan TK, Poon IKH, O'Brien-Simpson NM, Hill AF, Stinear TP, Kaparakis-Liaskos M. Staphylococcus aureus membrane vesicles contain immunostimulatory DNA, RNA and peptidoglycan that activate innate immune receptors and induce autophagy. J Extracell Vesicles 2021; 10:e12080. [PMID: 33815695 PMCID: PMC8015888 DOI: 10.1002/jev2.12080] [Citation(s) in RCA: 75] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 02/12/2021] [Accepted: 03/04/2021] [Indexed: 12/14/2022] Open
Abstract
Gram‐positive bacteria ubiquitously produce membrane vesicles (MVs), and although they contribute to biological functions, our knowledge regarding their composition and immunogenicity remains limited. Here we examine the morphology, contents and immunostimulatory functions of MVs produced by three Staphylococcus aureus strains; a methicillin resistant clinical isolate, a methicillin sensitive clinical isolate and a laboratory‐adapted strain. We observed differences in the number and morphology of MVs produced by each strain and showed that they contain microbe‐associated molecular patterns (MAMPs) including protein, nucleic acids and peptidoglycan. Analysis of MV‐derived RNA indicated the presence of small RNA (sRNA). Furthermore, we detected variability in the amount and composition of protein, nucleic acid and peptidoglycan cargo carried by MVs from each S. aureus strain. S. aureus MVs activated Toll‐like receptor (TLR) 2, 7, 8, 9 and nucleotide‐binding oligomerization domain containing protein 2 (NOD2) signalling and promoted cytokine and chemokine release by epithelial cells, thus identifying that MV‐associated MAMPs including DNA, RNA and peptidoglycan are detected by pattern recognition receptors (PRRs). Moreover, S. aureus MVs induced the formation of and colocalized with autophagosomes in epithelial cells, while inhibition of lysosomal acidification using bafilomycin A1 resulted in accumulation of autophagosomal puncta that colocalized with MVs, revealing the ability of the host to degrade MVs via autophagy. This study reveals the ability of DNA, RNA and peptidoglycan associated with MVs to activate PRRs in host epithelial cells, and their intracellular degradation via autophagy. These findings advance our understanding of the immunostimulatory roles of Gram‐positive bacterial MVs in mediating pathogenesis, and their intracellular fate within the host.
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Affiliation(s)
- Natalie J Bitto
- Department of Physiology Anatomy and Microbiology La Trobe University Melbourne Victoria 3086 Australia.,Research Centre for Extracellular Vesicles School of Molecular Sciences La Trobe University Melbourne Victoria 3086 Australia
| | - Lesley Cheng
- Research Centre for Extracellular Vesicles School of Molecular Sciences La Trobe University Melbourne Victoria 3086 Australia.,Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science La Trobe University Melbourne Victoria 3086 Australia
| | - Ella L Johnston
- Department of Physiology Anatomy and Microbiology La Trobe University Melbourne Victoria 3086 Australia.,Research Centre for Extracellular Vesicles School of Molecular Sciences La Trobe University Melbourne Victoria 3086 Australia
| | - Rishi Pathirana
- Department of Physiology Anatomy and Microbiology La Trobe University Melbourne Victoria 3086 Australia.,Research Centre for Extracellular Vesicles School of Molecular Sciences La Trobe University Melbourne Victoria 3086 Australia
| | - Thanh Kha Phan
- Research Centre for Extracellular Vesicles School of Molecular Sciences La Trobe University Melbourne Victoria 3086 Australia.,Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science La Trobe University Melbourne Victoria 3086 Australia
| | - Ivan K H Poon
- Research Centre for Extracellular Vesicles School of Molecular Sciences La Trobe University Melbourne Victoria 3086 Australia.,Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science La Trobe University Melbourne Victoria 3086 Australia
| | - Neil M O'Brien-Simpson
- Centre for Oral Health Research Melbourne Dental School Bio21 Institute The University of Melbourne Parkville Victoria 3010 Australia
| | - Andrew F Hill
- Research Centre for Extracellular Vesicles School of Molecular Sciences La Trobe University Melbourne Victoria 3086 Australia.,Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science La Trobe University Melbourne Victoria 3086 Australia
| | - Timothy P Stinear
- Department of Microbiology and Immunology Doherty Institute University of Melbourne Parkville Victoria 3010 Australia
| | - Maria Kaparakis-Liaskos
- Department of Physiology Anatomy and Microbiology La Trobe University Melbourne Victoria 3086 Australia.,Research Centre for Extracellular Vesicles School of Molecular Sciences La Trobe University Melbourne Victoria 3086 Australia
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28
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Sphingolipid-Containing Outer Membrane Vesicles Serve as a Delivery Vehicle To Limit Macrophage Immune Response to Porphyromonas gingivalis. Infect Immun 2021; 89:IAI.00614-20. [PMID: 33361202 PMCID: PMC8090959 DOI: 10.1128/iai.00614-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 12/17/2020] [Indexed: 01/01/2023] Open
Abstract
Sphingolipids (SLs) are essential structural components of mammalian cell membranes. Our group recently determined that the oral anaerobe Porphyromonas gingivalis delivers its SLs to host cells and that the ability of P. gingivalis to synthesize SLs limits the elicited host inflammatory response during cellular infection. Sphingolipids (SLs) are essential structural components of mammalian cell membranes. Our group recently determined that the oral anaerobe Porphyromonas gingivalis delivers its SLs to host cells and that the ability of P. gingivalis to synthesize SLs limits the elicited host inflammatory response during cellular infection. As P. gingivalis robustly produces outer membrane vesicles (OMVs), we hypothesized that OMVs serve as a delivery vehicle for SLs, that the SL status of the OMVs may impact cargo loading to OMVs, and that SL-containing OMVs limit elicited host inflammation similar to that observed by direct bacterial challenge. Transwell cell culture experiments determined that in comparison to the parent strain W83, the SL-null mutant elicited a hyperinflammatory immune response from THP-1 macrophage-like cells with elevated tumor necrosis factor alpha (TNF-α), interleukin 1β (IL-1β), and IL-6. Targeted assessment of Toll-like receptors (TLRs) identified elevated expression of TLR2, unchanged TLR4, and elevated expression of the adaptor molecules MyD88 and TRIF (Toll/IL-1 receptor domain-containing adaptor-inducing beta interferon) by SL-null P. gingivalis. No significant differences in gingipain activity were observed in our infection models, and both strains produced OMVs of similar sizes. Using comparative two-dimensional gel electrophoresis, we identified differences in the protein cargo of the OMVs between parent and SL-null strain. Importantly, use of purified OMVs recapitulated the cellular inflammatory response observed in the transwell system with whole bacteria. These findings provide new insights into the role of SLs in P. gingivalis OMV cargo assembly and expand our understanding of SL-OMVs as bacterial structures that modulate the host inflammatory response.
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Abstract
The release of extracellular vesicles (EVs) is a process conserved across the three domains of life. Amongst prokaryotes, EVs produced by Gram-negative bacteria, termed outer membrane vesicles (OMVs), were identified more than 50 years ago and a wealth of literature exists regarding their biogenesis, composition and functions. OMVs have been implicated in benefiting numerous metabolic functions of their parent bacterium. Additionally, OMVs produced by pathogenic bacteria have been reported to contribute to pathology within the disease setting. By contrast, the release of EVs from Gram-positive bacteria, known as membrane vesicles (MVs), has only been widely accepted within the last decade. As such, there is a significant disproportion in knowledge regarding MVs compared to OMVs. Here we provide an overview of the literature regarding bacterial membrane vesicles (BMVs) produced by pathogenic and commensal bacteria. We highlight the mechanisms of BMV biogenesis and their roles in assisting bacterial survival, in addition to discussing their functions in promoting disease pathologies and their potential use as novel therapeutic strategies.
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Affiliation(s)
- William J Gilmore
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Melbourne, VIC, Australia
- Research Centre for Extracellular Vesicles, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
| | - Natalie J Bitto
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Melbourne, VIC, Australia
- Research Centre for Extracellular Vesicles, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
| | - Maria Kaparakis-Liaskos
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Melbourne, VIC, Australia.
- Research Centre for Extracellular Vesicles, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia.
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30
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Mozaheb N, Mingeot-Leclercq MP. Membrane Vesicle Production as a Bacterial Defense Against Stress. Front Microbiol 2020; 11:600221. [PMID: 33362747 PMCID: PMC7755613 DOI: 10.3389/fmicb.2020.600221] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 11/16/2020] [Indexed: 12/15/2022] Open
Abstract
Membrane vesicles are the nano-sized vesicles originating from membranes. The production of membrane vesicles is a common feature among bacteria. Depending on the bacterial growth phase and environmental conditions, membrane vesicles show diverse characteristics. Various physiological and ecological roles have been attributed to membrane vesicles under both homeostatic and stressful conditions. Pathogens encounter several stressors during colonization in the hostile environment of host tissues. Nutrient deficiency, the presence of antibiotics as well as elements of the host’s immune system are examples of stressors threatening pathogens inside their host. To combat stressors and survive, pathogens have established various defensive mechanisms, one of them is production of membrane vesicles. Pathogens produce membrane vesicles to alleviate the destructive effects of antibiotics or other types of antibacterial treatments. Additionally, membrane vesicles can also provide benefits for the wider bacterial community during infections, through the transfer of resistance or virulence factors. Hence, given that membrane vesicle production may affect the activities of antibacterial agents, their production should be considered when administering antibacterial treatments. Besides, regarding that membrane vesicles play vital roles in bacteria, disrupting their production may suggest an alternative strategy for battling against pathogens. Here, we aim to review the stressors encountered by pathogens and shed light on the roles of membrane vesicles in increasing pathogen adaptabilities in the presence of stress-inducing factors.
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Affiliation(s)
- Negar Mozaheb
- Université catholique de Louvain (UCL), Louvain Drug Research Institute (LDRI), Cellular & Molecular Pharmacology Unit (FACM), Brussels, Belgium
| | - Marie-Paule Mingeot-Leclercq
- Université catholique de Louvain (UCL), Louvain Drug Research Institute (LDRI), Cellular & Molecular Pharmacology Unit (FACM), Brussels, Belgium
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31
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O'Bier NS, Patel DT, Oliver LD, Miller DP, Marconi RT. Development of an FhbB based chimeric vaccinogen that elicits antibodies that block Factor H binding and cleavage by the periopathogen Treponema denticola. Mol Oral Microbiol 2020; 36:50-57. [PMID: 33219611 DOI: 10.1111/omi.12325] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 11/13/2020] [Accepted: 11/17/2020] [Indexed: 12/17/2022]
Abstract
Treponema denticola is a proteolytic anaerobic spirochete and key contributor to periodontal disease of microbial etiology. As periodontal disease develops and progresses, T. denticola thrives in the hostile environment of the subgingival crevice by exploiting the negative regulatory activity of the complement protein, factor H (FH). FH bound to the cell surface receptor, FhbB (FH binding protein B), is competent to serve as a cofactor for the Factor I mediated-cleavage of the opsonin C3b. However, bound FH is ultimately cleaved by the T. denticola protease, dentilisin. As the T. denticola population expands, the rate of FH cleavage may exceed its rate of replenishment leading to local FH depletion and immune dysregulation culminating in tissue and ligament destruction and tooth loss. The goal of this study was to develop a T. denticola FhbB based-vaccine antigen that can block FH binding and cleavage and kill cells via antibody-mediated bactericidal activity. Tetra (FhbB-ch4) and pentavalent fhbB (FhbB-ch5) chimerics were engineered to have attenuated FH binding ability. The chimerics were immunogenic and elicited high-titer bactericidal and agglutinating antibody. Anti-Fhb-ch4 antisera blocked FH binding and cleavage by the T. denticola protease, dentilisin, in a dose dependent manner. Precedent for the use of FH binding proteins comes from the successful development of two FDA approved vaccines for type B Neiserria meningitidis. This study is the first to extend this approach to the development of a preventive or therapeutic vaccine (or monoclonal Ab) for periodontal disease.
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Affiliation(s)
- Nathaniel S O'Bier
- Department Microbiology and Immunology, Virginia Commonwealth University Medical Center, Richmond, VA, USA
| | - Dhara T Patel
- Department Microbiology and Immunology, Virginia Commonwealth University Medical Center, Richmond, VA, USA
| | - Lee D Oliver
- Department Microbiology and Immunology, Virginia Commonwealth University Medical Center, Richmond, VA, USA
| | - Daniel P Miller
- Department Microbiology and Immunology, Virginia Commonwealth University Medical Center, Richmond, VA, USA
| | - Richard T Marconi
- Department Microbiology and Immunology, Virginia Commonwealth University Medical Center, Richmond, VA, USA
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32
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Marre ATDO, Domingues RMCP, Lobo LA. Adhesion of anaerobic periodontal pathogens to extracellular matrix proteins. Braz J Microbiol 2020; 51:1483-1491. [PMID: 32557245 PMCID: PMC7688880 DOI: 10.1007/s42770-020-00312-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 05/29/2020] [Indexed: 02/06/2023] Open
Abstract
Extracellular matrix (ECM) proteins are highly abundant in the human body and can be found in various tissues, most prominently in connective tissue and basement membrane. For invasive bacterial pathogens, these structures function as physical barriers that block access to underlying tissues. The ability to bind and degrade these barriers is important for the establishment of infections and migration to other body sites. In the oral cavity, the ECM and the basement membrane (BM) are important components of the Junctional epithelium (JE) that closes the gap between the teeth surface and the mucosa. In periodontitis, the JE is breached by invading pathogenic bacteria, particularly strict anaerobic species. In periodontitis, invading microorganisms induce an unregulated and destructive host response through polymicrobial synergism and dysbiosis that attracts immune cells and contributes to the destruction of connective tissue and bone in the periodontal pocket. Colonization of the periodontal pocket is the first step to establish this infection, and binding to ECM is a major advantage in this site. Several species of strict anaerobic bacteria are implicated in acute and chronic periodontitis, and although binding to ECM proteins was studied in these species, few adhesins were identified so far, and the mechanisms involved in adhesion are largely unidentified. This review summarizes the data available on the interaction of strict anaerobic bacteria and components of the ECM.
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Affiliation(s)
- Andressa Temperine de Oliveira Marre
- Medical Microbiology Department, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro - UFRJ, CCS - Centro de Ciências da Saúde, 373 Avenida Carlos Chagas Filho, Bloco I - sala I2-06, Cidade Universitária, Rio de Janeiro, 21941-902, Brazil
| | - Regina M C P Domingues
- Medical Microbiology Department, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro - UFRJ, CCS - Centro de Ciências da Saúde, 373 Avenida Carlos Chagas Filho, Bloco I - sala I2-06, Cidade Universitária, Rio de Janeiro, 21941-902, Brazil
| | - Leandro A Lobo
- Medical Microbiology Department, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro - UFRJ, CCS - Centro de Ciências da Saúde, 373 Avenida Carlos Chagas Filho, Bloco I - sala I2-06, Cidade Universitária, Rio de Janeiro, 21941-902, Brazil.
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33
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Bao K, Li X, Poveda L, Qi W, Selevsek N, Gumus P, Emingil G, Grossmann J, Diaz PI, Hajishengallis G, Bostanci N, Belibasakis GN. Proteome and Microbiome Mapping of Human Gingival Tissue in Health and Disease. Front Cell Infect Microbiol 2020; 10:588155. [PMID: 33117738 PMCID: PMC7566166 DOI: 10.3389/fcimb.2020.588155] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 09/02/2020] [Indexed: 12/15/2022] Open
Abstract
Efforts to map gingival tissue proteomes and microbiomes have been hampered by lack of sufficient tissue extraction methods. The pressure cycling technology (PCT) is an emerging platform for reproducible tissue homogenisation and improved sequence retrieval coverage. Therefore, we employed PCT to characterise the proteome and microbiome profiles in healthy and diseased gingival tissue. Healthy and diseased contralateral gingival tissue samples (total n = 10) were collected from five systemically healthy individuals (51.6 ± 4.3 years) with generalised chronic periodontitis. The tissues were then lysed and digested using a Barocycler, proteins were prepared and submitted for mass spectrometric analysis and microbiome DNA for 16S rRNA profiling analysis. Overall, 1,366 human proteins were quantified (false discovery rate 0.22%), of which 69 proteins were differentially expressed (≥2 peptides and p < 0.05, 62 up, 7 down) in periodontally diseased sites, compared to healthy sites. These were primarily extracellular or vesicle-associated proteins, with functions in molecular transport. On the microbiome level, 362 species-level operational taxonomic units were identified. Of those, 14 predominant species accounted for >80% of the total relative abundance, whereas 11 proved to be significantly different between healthy and diseased sites. Among them, Treponema sp. HMT253 and Fusobacterium naviforme and were associated with disease sites and strongly interacted (r > 0.7) with 30 and 6 up-regulated proteins, respectively. Healthy-site associated strains Streptococcus vestibularis, Veillonella dispar, Selenomonas sp. HMT478 and Leptotrichia sp. HMT417 showed strong negative interactions (r < −0.7) with 31, 21, 9, and 18 up-regulated proteins, respectively. In contrast the down-regulated proteins did not show strong interactions with the regulated bacteria. The present study identified the proteomic and intra-tissue microbiome profile of human gingiva by employing a PCT-assisted workflow. This is the first report demonstrating the feasibility to analyse full proteome profiles of gingival tissues in both healthy and disease sites, while deciphering the tissue site-specific microbiome signatures.
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Affiliation(s)
- Kai Bao
- Division of Oral Diseases, Department of Dental Medicine, Karolinska Insitutet, Huddinge, Sweden
| | - Xiaofei Li
- Department of Basic and Translational Sciences, School of Dental Medicine, Philadelphia, PA, United States
| | - Lucy Poveda
- Functional Genomic Centre, ETH Zurich and University of Zurich, Zürich, Switzerland
| | - Weihong Qi
- Functional Genomic Centre, ETH Zurich and University of Zurich, Zürich, Switzerland
| | | | - Pinar Gumus
- Department of Periodontology, School of Dentistry, Ege University, Izmir, Turkey
| | - Gulnur Emingil
- Department of Periodontology, School of Dentistry, Ege University, Izmir, Turkey
| | - Jonas Grossmann
- Functional Genomic Centre, ETH Zurich and University of Zurich, Zürich, Switzerland
| | - Patricia I Diaz
- Department of Oral Biology, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - George Hajishengallis
- Department of Basic and Translational Sciences, School of Dental Medicine, Philadelphia, PA, United States
| | - Nagihan Bostanci
- Division of Oral Diseases, Department of Dental Medicine, Karolinska Insitutet, Huddinge, Sweden
| | - Georgios N Belibasakis
- Division of Oral Diseases, Department of Dental Medicine, Karolinska Insitutet, Huddinge, Sweden
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34
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Kamarajan P, Ateia I, Shin JM, Fenno JC, Le C, Zhan L, Chang A, Darveau R, Kapila YL. Periodontal pathogens promote cancer aggressivity via TLR/MyD88 triggered activation of Integrin/FAK signaling that is therapeutically reversible by a probiotic bacteriocin. PLoS Pathog 2020; 16:e1008881. [PMID: 33002094 PMCID: PMC7529280 DOI: 10.1371/journal.ppat.1008881] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 08/12/2020] [Indexed: 12/13/2022] Open
Abstract
Epidemiological studies reveal significant associations between periodontitis and oral cancer. However, knowledge about the contribution of periodontal pathogens to oral cancer and potential regulatory mechanisms involved is limited. Previously, we showed that nisin, a bacteriocin and commonly used food preservative, reduced oral cancer tumorigenesis and extended the life expectancy in tumor-bearing mice. In addition, nisin has antimicrobial effects on key periodontal pathogens. Thus, the purpose of this study was to test the hypothesis that key periodontal pathogens (Porphyromonas gingivalis, Treponema denticola, and Fusobacterium nucleatum) promote oral cancer via specific host-bacterial interactions, and that bacteriocin/nisin therapy may modulate these responses. All three periodontal pathogens enhanced oral squamous cell carcinoma (OSCC) cell migration, invasion, tumorsphere formation, and tumorigenesis in vivo, without significantly affecting cell proliferation or apoptosis. In contrast, oral commensal bacteria did not affect OSCC cell migration. Pathogen-enhanced OSCC cell migration was mediated via integrin alpha V and FAK activation, since stably blocking alpha V or FAK expression abrogated these effects. Nisin inhibited these pathogen-mediated processes. Further, Treponema denticola induced TLR2 and 4 and MyD88 expression. Stable suppression of MyD88 significantly inhibited Treponema denticola-induced FAK activation and abrogated pathogen-induced migration. Together, these data demonstrate that periodontal pathogens contribute to a highly aggressive cancer phenotype via crosstalk between TLR/MyD88 and integrin/FAK signaling. Nisin can modulate these pathogen-mediated effects, and thus has therapeutic potential as an antimicrobial and anti-tumorigenic agent.
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Affiliation(s)
- Pachiyappan Kamarajan
- Department of Orofacial Sciences, School of Dentistry, University of California, San Francisco, CA, United States of America
- Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, MI, United States of America
| | - Islam Ateia
- Department of Oral Medicine and Periodontology, Mansoura University, Mansoura, Egypt
| | - Jae M. Shin
- Department of Cariology, Restorative Sciences, and Endodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, United States of America
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, United States of America
| | - J. Christopher Fenno
- Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann arbor, MI, United States of America
| | - Charles Le
- Department of Orofacial Sciences, School of Dentistry, University of California, San Francisco, CA, United States of America
| | - Ling Zhan
- Department of Orofacial Sciences, School of Dentistry, University of California, San Francisco, CA, United States of America
| | - Ana Chang
- Department of Periodontics, Oral Health Sciences, School of Dentistry, University of Washington, Seattle, WA, United States of America
| | - Richard Darveau
- Department of Periodontics, Oral Health Sciences, School of Dentistry, University of Washington, Seattle, WA, United States of America
| | - Yvonne L. Kapila
- Department of Orofacial Sciences, School of Dentistry, University of California, San Francisco, CA, United States of America
- Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, MI, United States of America
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35
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Oral spirochetes: Pathogenic mechanisms in periodontal disease. Microb Pathog 2020; 144:104193. [PMID: 32304795 DOI: 10.1016/j.micpath.2020.104193] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 04/07/2020] [Indexed: 12/14/2022]
Abstract
Periodontitis is an infectious inflammatory disease resulting from infection of biofilm forming bacteria. Several bacterial factors regulate inflammatory response and cause to tissue damage and loss of connection between gingival and tooth. Since bacterial virulence factors and also host immune responses have role, understanding of periodontal disease is complex, in overall we can say that in this disease epithelium is deleted by bacteria. Oral spirochetes are related to periodontitis, among them, Treponema denticola, have been associated with periodontal diseases such as early-onset periodontitis, necrotizing ulcerative gingivitis, and acute pericoronitis. This review will analyse mechanisms of pathogenesis of spirochetes in periodontitis. Microorganisms cause destruction of gingival tissue by two mechanisms. In one, damage results from the direct action of bacterial enzymes and cytotoxic products of bacterial metabolism. In the other, only bacterial components have role, and tissue destruction is the inevitable side effect of a subverted and exaggerated host inflammatory response to plaque antigens.
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36
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Silbergleit M, Vasquez AA, Miller CJ, Sun J, Kato I. Oral and intestinal bacterial exotoxins: Potential linked to carcinogenesis. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2020; 171:131-193. [PMID: 32475520 DOI: 10.1016/bs.pmbts.2020.02.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Growing evidence suggests that imbalances in resident microbes (dysbiosis) can promote chronic inflammation, immune-subversion, and production of carcinogenic metabolites, thus leading to neoplasia. Yet, evidence to support a direct link of individual bacteria species to human sporadic cancer is still limited. This chapter focuses on several emerging bacterial toxins that have recently been characterized for their potential oncogenic properties toward human orodigestive cancer and the presence of which in human tissue samples has been documented. These include cytolethal distending toxins produced by various members of gamma and epsilon Proteobacteria, Dentilisin from mammalian oral Treponema, Pasteurella multocida toxin, two Fusobacterial toxins, FadA and Fap2, Bacteroides fragilis toxin, colibactin, cytotoxic necrotizing factors and α-hemolysin from Escherichia coli, and Salmonella enterica AvrA. It was clear that these bacterial toxins have biological activities to induce several hallmarks of cancer. Some toxins directly interact with DNA or chromosomes leading to their breakdowns, causing mutations and genome instability, and others modulate cell proliferation, replication and death and facilitate immune evasion and tumor invasion, prying specific oncogene and tumor suppressor pathways, such as p53 and β-catenin/Wnt. In addition, most bacterial toxins control tumor-promoting inflammation in complex and diverse mechanisms. Despite growing laboratory evidence to support oncogenic potential of selected bacterial toxins, we need more direct evidence from human studies and mechanistic data from physiologically relevant experimental animal models, which can reflect chronic infection in vivo, as well as take bacterial-bacterial interactions among microbiome into consideration.
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Affiliation(s)
| | - Adrian A Vasquez
- Department of Civil and Environmental Engineering, Wayne State University, Healthy Urban Waters, Detroit, MI, United States
| | - Carol J Miller
- Department of Civil and Environmental Engineering, Wayne State University, Healthy Urban Waters, Detroit, MI, United States
| | - Jun Sun
- Department of Medicine, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Ikuko Kato
- Department of Oncology, Wayne State University School of Medicine, Detroit, MI, United States; Department of Pathology, Wayne State University School of Medicine, Detroit, MI, United States.
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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: 125] [Impact Index Per Article: 31.3] [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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Tsai YL, Tsai WC, Qing Z, Chang CJ. Dichotomous effects of microbial membrane vesicles on the regulation of immunity. MEDICINE IN MICROECOLOGY 2020. [DOI: 10.1016/j.medmic.2020.100009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Takahashi N, Sulijaya B, Yamada-Hara M, Tsuzuno T, Tabeta K, Yamazaki K. Gingival epithelial barrier: regulation by beneficial and harmful microbes. Tissue Barriers 2019; 7:e1651158. [PMID: 31389292 DOI: 10.1080/21688370.2019.1651158] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The gingival epithelium acts as a physical barrier to separate the biofilm from the gingival tissue, providing the first line of defense against bacterial invasion in periodontal disease. Disruption of the gingival epithelial barrier, and the subsequent penetration of exogenous pathogens into the host tissues, triggers an inflammatory response, establishing chronic infection. Currently, more than 700 different bacterial species have been identified in the oral cavity, some of which are known to be periodontopathic. These bacteria contribute to epithelial barrier dysfunction in the gingiva by producing several virulence factors. However, some bacteria in the oral cavity appear to be beneficial, helping gingival epithelial cells maintain their integrity and barrier function. This review aims to discuss current findings regarding microorganism interactions and epithelial barrier function in the oral cavity, with reference to investigations in the gut, where this interaction has been extensively studied.
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Affiliation(s)
- Naoki Takahashi
- Division of Periodontology, Department of Oral Biological Science, Faculty of Dentistry, Niigata University , Niigata , Japan.,Research Center for Advanced Oral Science, Graduate School of Medical and Dental Sciences, Niigata University , Niigata , Japan
| | - Benso Sulijaya
- Division of Periodontology, Department of Oral Biological Science, Faculty of Dentistry, Niigata University , Niigata , Japan.,Research Unit for Oral-Systemic Connection, Division of Oral Science for Health Promotion, Graduate School of Medical and Dental Sciences, Niigata University , Niigata , Japan.,Department of Periodontology, Faculty of Dentistry, Universitas Indonesia , Jakarta , Indonesia
| | - Miki Yamada-Hara
- Division of Periodontology, Department of Oral Biological Science, Faculty of Dentistry, Niigata University , Niigata , Japan.,Research Unit for Oral-Systemic Connection, Division of Oral Science for Health Promotion, Graduate School of Medical and Dental Sciences, Niigata University , Niigata , Japan
| | - Takahiro Tsuzuno
- Division of Periodontology, Department of Oral Biological Science, Faculty of Dentistry, Niigata University , Niigata , Japan.,Research Unit for Oral-Systemic Connection, Division of Oral Science for Health Promotion, Graduate School of Medical and Dental Sciences, Niigata University , Niigata , Japan
| | - Koichi Tabeta
- Division of Periodontology, Department of Oral Biological Science, Faculty of Dentistry, Niigata University , Niigata , Japan
| | - Kazuhisa Yamazaki
- Research Unit for Oral-Systemic Connection, Division of Oral Science for Health Promotion, Graduate School of Medical and Dental Sciences, Niigata University , Niigata , Japan
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40
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Abstract
Outer membrane vesicles (OMVs) are nanosized proteoliposomes derived from the outer membrane of Gram-negative bacteria. They are ubiquitously produced both in culture and during infection and are now recognized to play crucial roles during host-microbe interactions. OMVs can transport a broad range of chemically diverse cargoes, including lipids and lipopolysaccharides, membrane-embedded and associated proteins and small molecules, peptidoglycan, and nucleic acids. Particularly, virulence factors such as adhesins and toxins are often enriched in OMVs. Here we discuss a variety of ways in which OMVs facilitate host-microbe interactions, including their contributions to biofilm formation, nutrient scavenging, and modulation of host cell function. We particularly examine recent findings regarding OMV-host cell interactions in the oral cavity and the gastrointestinal tract.
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41
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Veith PD, Glew MD, Gorasia DG, Chen D, O’Brien-Simpson NM, Reynolds EC. Localization of Outer Membrane Proteins in Treponema denticola by Quantitative Proteome Analyses of Outer Membrane Vesicles and Cellular Fractions. J Proteome Res 2019; 18:1567-1581. [DOI: 10.1021/acs.jproteome.8b00860] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Paul D. Veith
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Michelle D. Glew
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Dhana G. Gorasia
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Dina Chen
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Neil M. O’Brien-Simpson
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Eric C. Reynolds
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
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Kikuchi Y, Kimizuka R, Kato T, Okuda K, Kokubu E, Ishihara K. Treponema denticola Induces Epithelial Barrier Dysfunction in Polarized Epithelial Cells. THE BULLETIN OF TOKYO DENTAL COLLEGE 2018; 59:265-275. [PMID: 30333370 DOI: 10.2209/tdcpublication.2017-0052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Treponema denticola, an anaerobic spirochete found mainly in the oral cavity, is associated with periodontal disease and has a variety of virulence factors. Although in vitro studies have shown that T. denticola is able to penetrate epithelial cell monolayers, its effect on the epithelial barrier junction is not known. Human gingival epithelial cells are closely associated with adjacent membranes, forming barriers in the presence of tight junction proteins, including zonula occludens-1 (ZO-1), claudin-1, and occludin. Tight junction proteins are also expressed by Madin-Darby canine kidney (MDCK) cells in culture. In this study, the MDCK cell profile was investigated following infection with T. denticola (ATCC 35405) wild-type, as well as with its dentilisin-deficient mutant, K1. Basolateral exposure of MDCK cell monolayers to T. denticola at a multiplicity of infection (MOI) of 104 resulted in a decrease in transepithelial electrical resistance (TER). Transepithelial electrical resistance in MDCK cell monolayers also decreased following apical exposure to T. denticola (MOI=104), although this took longer with basolateral exposure. The effect on the TER was time-dependent and required the presence of live bacteria. Meanwhile, MDCK cell viability showed a decrease with either basolateral or apical exposure. Immunofluorescence analysis demonstrated decreases in the amounts of immunoreactive ZO-1 and claudin-1 in association with disruption of cell-cell junctions in MDCK cells exposed apically or basolaterally to T. denticola. Western blot analysis demonstrated degradation of ZO-1 and claudin-1 in culture lysates derived from T. denticola-exposed MDCK cells, suggesting a bacteria-induced protease capable of cleaving these tight junction proteins.
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Affiliation(s)
- Yuichiro Kikuchi
- Department of Microbiology, Tokyo Dental College.,Oral Health Science Center, Tokyo Dental College
| | | | - Tetsuo Kato
- Laboratory of Chemistry, Tokyo Dental College
| | | | - Eitoyo Kokubu
- Department of Microbiology, Tokyo Dental College.,Oral Health Science Center, Tokyo Dental College
| | - Kazuyuki Ishihara
- Department of Microbiology, Tokyo Dental College.,Oral Health Science Center, Tokyo Dental College
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43
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Tegels B, Oliver L, Miller D, Marconi R. Plasminogen binding and degradation byTreponema denticola:Identification of the plasminogen binding interface on the FhbB protein. Mol Oral Microbiol 2018; 33:249-256. [DOI: 10.1111/omi.12221] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/26/2018] [Indexed: 12/13/2022]
Affiliation(s)
- B.K. Tegels
- Department of Microbiology and Immunology; Virginia Commonwealth University Medical Center; Richmond VA USA
| | - L.D. Oliver
- Department of Microbiology and Immunology; Virginia Commonwealth University Medical Center; Richmond VA USA
| | - D.P. Miller
- Department of Microbiology and Immunology; Virginia Commonwealth University Medical Center; Richmond VA USA
| | - R.T. Marconi
- Department of Microbiology and Immunology; Virginia Commonwealth University Medical Center; Richmond VA USA
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44
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Simões M, Hugo A, Alves P, Pérez P, Gómez-Zavaglia A, Simões P. Long term stability and interaction with epithelial cells of freeze-dried pH-responsive liposomes functionalized with cholesterol-poly(acrylic acid). Colloids Surf B Biointerfaces 2018; 164:50-57. [DOI: 10.1016/j.colsurfb.2018.01.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 01/03/2018] [Accepted: 01/15/2018] [Indexed: 11/25/2022]
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Elmanfi S, Ma X, Sintim HO, Könönen E, Syrjänen S, Gursoy UK. Quorum-sensing molecule dihydroxy-2,3-pentanedione and its analogs as regulators of epithelial integrity. J Periodontal Res 2018; 53:414-421. [PMID: 29344966 DOI: 10.1111/jre.12528] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/08/2017] [Indexed: 12/28/2022]
Abstract
BACKGROUND AND OBJECTIVE Quorum-sensing molecules regulate the behavior of bacteria within biofilms and at the same time elicit an immune response in host tissues. Our aim was to investigate the regulatory role of dihydroxy-2,3-pentanedione (DPD), the precursor of universal autoinducer-2 (AI-2), and its analogs (ethyl-DPD, butyl-DPD and isobutyl-DPD) in the integrity of gingival epithelial cells. MATERIAL AND METHODS Human gingival keratinocytes were incubated with four concentrations (10 μmol L-1 , 1 μmol L-1 , 100 nmol L-1 and 10 nmol L-1 ) of DPD and its analogs for 24 hours. The numbers of viable cells were determined using a proliferation kit, matrix metalloproteinase (MMP)-2 and -9 activities were determined by gelatin zymography, and expression of occludin protein and occludin mRNA were determined by western blotting and RT-qPCR, respectively. RESULTS Increased cell proliferation was observed in gingival keratinocytes incubated with 100 nmol L-1 of butyl-DPD. MMP-9 activity was elevated in cells incubated with 10 μmol L-1 of ethyl-DPD. On the other hand, MMP-2 activity did not show any significant change when gingival keratinocytes were incubated with or without DPD or analogs. Western blot analyses demonstrated five forms (105, 61, 52.2, 44 and 37 kDa) of occludin. Incubation with 1 μmol L-1 and 100 nmol L-1 of DPD and with 10 nmol L-1 of ethyl-DPD increased dimeric (105 kDa) forms of occludin, while incubation with 100 nmol L-1 of isobutyl-DPD increased monomeric (61 kDa) forms. DPD and ethyl-DPD decreased, and 100 nmol L-1 of isobutyl-DPD and 10 nmol L-1 of butyl-DPD increased, the monomeric (52.2 kDa and 44 kDa) forms of occludin, whereas ethyl-DPD decreased and isobutyl-DPD increased, the low-molecular-weight (37 kDa) forms. According to RT-qPCR analysis, the exposure of gingival keratinocytes to 10 μmol L-1 of isobutyl-DPD up-regulated expression of occludin. CONCLUSION The results indicate that isobutyl-DPD has the potential to enhance the integrity of the epithelium by stimulating the formation of occluding, without affecting the proliferation or gelatinolytic enzyme activities of the exposed cells. The modulatory effect of an AI-2 analog on the epithelial cell response is shown for the first time.
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Affiliation(s)
- S Elmanfi
- Department of Periodontology, Institute of Dentistry, University of Turku, Turku, Finland
| | - X Ma
- Department of Chemistry, Purdue Institute for Drug Discovery, Purdue University, West Lafayette, IN, USA.,Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, USA
| | - H O Sintim
- Department of Chemistry, Purdue Institute for Drug Discovery, Purdue University, West Lafayette, IN, USA.,Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, USA
| | - E Könönen
- Department of Periodontology, Institute of Dentistry, University of Turku, Turku, Finland.,Oral Health Care, Welfare Division, Turku, Finland
| | - S Syrjänen
- Department of Oral Pathology, Institute of Dentistry, University of Turku, Turku, Finland.,Department of Pathology, Turku University Hospital, Turku, Finland
| | - U K Gursoy
- Department of Periodontology, Institute of Dentistry, University of Turku, Turku, Finland
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46
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Ateia IM, Sutthiboonyapan P, Kamarajan P, Jin T, Godovikova V, Kapila YL, Fenno JC. Treponema denticola increases MMP-2 expression and activation in the periodontium via reversible DNA and histone modifications. Cell Microbiol 2018; 20. [PMID: 29205773 DOI: 10.1111/cmi.12815] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/03/2017] [Accepted: 11/28/2017] [Indexed: 12/21/2022]
Abstract
Host-derived matrix metalloproteinases (MMPs) and bacterial proteases mediate destruction of extracellular matrices and supporting alveolar bone in periodontitis. The Treponema denticola dentilisin protease induces MMP-2 expression and activation in periodontal ligament (PDL) cells, and dentilisin-mediated activation of pro-MMP-2 is required for cellular fibronectin degradation. Here, we report that T. denticola regulates MMP-2 expression through epigenetic modifications in the periodontium. PDL cells were treated with epigenetic enzyme inhibitors before or after T. denticola challenge. Fibronectin fragmentation, MMP-2 expression, and activation were assessed by immunoblot, zymography, and qRT-PCR, respectively. Chromatin modification enzyme expression in T. denticola-challenged PDL cells and periodontal tissues were evaluated using gene arrays. Several classes of epigenetic enzymes showed significant alterations in transcription in diseased tissue and T. denticola-challenged PDL cells. T. denticola-mediated MMP-2 expression and activation were significantly reduced in PDL cells treated with inhibitors of aurora kinases and histone deacetylases. In contrast, DNA methyltransferase inhibitors had little effect, and inhibitors of histone acetyltransferases, methyltransferases, and demethylases exacerbated T. denticola-mediated MMP-2 expression and activation. Chronic epigenetic changes in periodontal tissues mediated by T. denticola or other oral microbes may contribute to the limited success of conventional treatment of chronic periodontitis and may be amenable to therapeutic reversal.
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Affiliation(s)
- Islam M Ateia
- Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA.,Department of Periodontics and Oral Medicine, University of Mansoura Faculty of Dentistry, Mansoura, Egypt
| | - Pimchanok Sutthiboonyapan
- Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA.,Department of Periodontology, Chulalongkorn University Faculty of Dentistry, Bangkok, Thailand
| | - Pachiyappan Kamarajan
- Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA.,Department of Orofacial Sciences, University of California San Francisco School of Dentistry, San Francisco, CA, USA
| | - Taocong Jin
- Office of Research, University of Michigan School of Dentistry, Ann Arbor, MI, USA
| | - Valentina Godovikova
- Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, Ann Arbor, MI, USA
| | - Yvonne L Kapila
- Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA.,Department of Orofacial Sciences, University of California San Francisco School of Dentistry, San Francisco, CA, USA
| | - J Christopher Fenno
- Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, Ann Arbor, MI, USA
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47
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Abstract
Bacterial membrane vesicles (BMVs) are closed spherical nanostructures that are shed naturally and ubiquitously by most bacterial species both in vivo and in vitro. Researchers have elucidated their roles in long-distance transport of a wide array of cargoes, such as proteins, toxins, antigens, virulence factors, microbicidal agents and antibiotics. Given that these natural carriers are important players in intercellular communication, it has been hypothesized that they are equally well attuned for transport and delivery of exogenous therapeutic cargoes. Additionally, BMVs appear to possess specific properties that enable their utilization as drug delivery vehicles. These include their ability to evade the host immune system, protection of the therapeutic payload and natural stability. Using bioengineering approaches, BMVs have been applied as carriers of therapeutic moieties in vaccines and for targeted delivery in cancer. In this article, we explore BMVs from the perspective of understanding their applicability to drug delivery. BMV biology, including biogenesis, physiology and pathology, is briefly reviewed. Practical issues related to bioprocessing, loading of therapeutic moieties and characterization for enabling scalability and commercial viability are evaluated. Finally, challenges to clinical translation and rational design approaches for novel BMV formulations are presented. Although the realization of the full potential of BMVs in drug delivery hinges on the development of scalable approaches for their production as well as the refinement of targeting and loading methods, they are promising candidates for development of a novel generation of drug delivery vehicles in future.
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Affiliation(s)
- Sapna Jain
- Implants, Devices and Drug Delivery Systems Laboratory, Centre for Biodesign and Diagnostics, Translational Health Science and Technology Institute, Faridabad, Haryana, India
| | - Jonathan Pillai
- Implants, Devices and Drug Delivery Systems Laboratory, Centre for Biodesign and Diagnostics, Translational Health Science and Technology Institute, Faridabad, Haryana, India
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48
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Cecil JD, O'Brien-Simpson NM, Lenzo JC, Holden JA, Singleton W, Perez-Gonzalez A, Mansell A, Reynolds EC. Outer Membrane Vesicles Prime and Activate Macrophage Inflammasomes and Cytokine Secretion In Vitro and In Vivo. Front Immunol 2017; 8:1017. [PMID: 28890719 PMCID: PMC5574916 DOI: 10.3389/fimmu.2017.01017] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 08/08/2017] [Indexed: 12/16/2022] Open
Abstract
Outer membrane vesicles (OMVs) are proteoliposomes blebbed from the surface of Gram-negative bacteria. Chronic periodontitis is associated with an increase in subgingival plaque of Gram-negative bacteria, Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia. In this study, we investigated the immune-modulatory effects of P. gingivalis, T. denticola, and T. forsythia OMVs on monocytes and differentiated macrophages. All of the bacterial OMVs were phagocytosed by monocytes, M(naïve) and M(IFNγ) macrophages in a dose-dependent manner. They also induced NF-κB activation and increased TNFα, IL-8, and IL-1β cytokine secretion. P. gingivalis OMVs were also found to induce anti-inflammatory IL-10 secretion. Although unprimed monocytes and macrophages were resistant to OMV-induced cell death, lipopolysaccharide or OMV priming resulted in a significantly reduced cell viability. P. gingivalis, T. denticola, and T. forsythia OMVs all activated inflammasome complexes, as monitored by IL-1β secretion and ASC speck formation. ASC was critical for OMV-induced inflammasome formation, while AIM2-/- and Caspase-1-/- cells had significantly reduced inflammasome formation and NLRP3-/- cells exhibited a slight reduction. OMVs were also found to provide both priming and activation of the inflammasome complex. High-resolution microscopy and flow cytometry showed that P. gingivalis OMVs primed and activated macrophage inflammasomes in vivo with 80% of macrophages exhibiting inflammasome complex formation. In conclusion, periodontal pathogen OMVs were found to have significant immunomodulatory effects upon monocytes and macrophages and should therefore influence pro-inflammatory host responses associated with disease.
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Affiliation(s)
- Jessica D Cecil
- Oral Health CRC, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Neil M O'Brien-Simpson
- Oral Health CRC, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Jason C Lenzo
- Oral Health CRC, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - James A Holden
- Oral Health CRC, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - William Singleton
- Oral Health CRC, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Alexis Perez-Gonzalez
- Oral Health CRC, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Ashley Mansell
- Department of Molecular and Translational Science, Monash University, Clayton, VIC, Australia
| | - Eric C Reynolds
- Oral Health CRC, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, VIC, Australia
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49
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Abstract
Outer Membrane Vesicles (OMVs) of Gram-negative bacteria are spherical membrane-enclosed entities of endocytic origin. Reported in the consortia of different bacterial species, production of OMVs into extracellular milieu seems essential for their survival. Enriched with bioactive proteins, toxins, and virulence factors, OMVs play a critical role in the bacteria-bacteria and bacteria-host interactions. Emergence of OMVs as distinct cellular entities helps bacteria in adaptating to diverse niches, in competing with other bacteria to protect members of producer species and more importantly play a crucial role in host-pathogen interaction. Composition of OMV, their ability to modulate host immune response, along with coordinated secretion of bacterial effector proteins, endows them with the armory, which can withstand hostile environments. Study of the OMV production under natural and diverse stress conditions has broadened the horizons, and also opened new frontiers in delineating the molecular machinery involved in disease pathogenesis. Playing diverse biological and pathophysiological functions, OMVs hold a great promise in enabling resurgence of bacterial diseases, in concomitance with the steep decline in the efficiency of antibiotics. Having multifaceted role, their emergence as a causative agent for a series of infectious diseases increases the probability for their exploitation in the development of effective diagnostic tools and as vaccines against diverse pathogenic species of Gram-negative origin.
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Affiliation(s)
- Arif Tasleem Jan
- Department of Medical Biotechnology, Yeungnam UniversityGyeongsan, South Korea
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50
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The microbiome of the lung and its extracellular vesicles in nonsmokers, healthy smokers and COPD patients. Exp Mol Med 2017; 49:e316. [PMID: 28408748 PMCID: PMC5420800 DOI: 10.1038/emm.2017.7] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 11/16/2016] [Accepted: 11/17/2016] [Indexed: 12/16/2022] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease, and bacterial infection plays a role in its pathogenesis. Bacteria secrete nanometer-sized extracellular vesicles (EVs), which may induce more immune dysfunction and inflammation than the bacteria themselves. We hypothesized that the microbiome of lung EVs might have distinct characteristics depending on the presence of COPD and smoking status. We analyzed and compared the microbiomes of 13 nonsmokers with normal spirometry, 13 smokers with normal spirometry (healthy smokers) and 13 patients with COPD by using 16S ribosomal RNA gene sequencing of surgical lung tissue and lung EVs. Subjects were matched for age and sex in all groups and for smoking levels in the COPD and healthy smoker groups. Each group included 12 men and 1 woman with the same mean age of 65.5 years. In all groups, EVs consistently showed more operational taxonomic units (OTUs) than lung tissue. In the healthy smoker and COPD groups, EVs had a higher Shannon index and a lower Simpson index than lung tissue and this trend was more prominent in the COPD group. Principal component analysis (PCA) showed clusters based on sample type rather than participants' clinical characteristics. Stenotrophomonas, Propionibacterium and Alicyclobacillus were the most commonly found genera. Firmicutes were highly present in the EVs of the COPD group compared with other samples or groups. Our analysis of the lung microbiome revealed that the bacterial communities present in the EVs and in the COPD group possessed distinct characteristics with differences in the OTUs, diversity indexes and PCA clustering.
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