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Naskar S, Sriraman N, Sarkar A, Mahajan N, Sarkar K. Tumor antigen presentation and the associated signal transduction during carcinogenesis. Pathol Res Pract 2024; 261:155485. [PMID: 39088877 DOI: 10.1016/j.prp.2024.155485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 07/17/2024] [Accepted: 07/22/2024] [Indexed: 08/03/2024]
Abstract
Numerous developments have been achieved in the study and treatment of cancer throughout the decades that it has been common. After decades of research, about 100 different kinds of cancer have been found, each with unique subgroups within certain organs. This has significantly expanded our understanding of the illness. A mix of genetic, environmental, and behavioral variables contribute to the complicated and diverse process of cancer formation. Mutations, or changes in the DNA sequence, are crucial to the development of cancer. These mutations have the ability to downregulate the expression and function of Major Histocompatibility Complex class I (MHC I) and MHCII receptors, as well as activate oncogenes and inactivate tumor suppressor genes. Cancer cells use this tactic to avoid being recognized by cytotoxic CD8+T lymphocytes, which causes issues with antigen presentation and processing. This review goes into great length into the PI3K pathway, changes to MHC I, and positive impacts of tsMHC-II on disease-free survival and overall survival and the involvement of dendritic cells (DCs) in different tumor microenvironments. The vital functions that the PI3K pathway and its link to the mTOR pathway are highlighted and difficulties in developing effective cancer targeted therapies and feedback systems has also been mentioned, where resistance mechanisms include RAS-mediated oncogenic changes and active PI3K signalling.
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Affiliation(s)
- Sohom Naskar
- Department of Biotechnology, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu 603203, India
| | - Nawaneetan Sriraman
- Department of Biotechnology, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu 603203, India
| | - Ankita Sarkar
- Department of Biotechnology, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu 603203, India
| | - Nitika Mahajan
- Department of Biotechnology, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu 603203, India
| | - Koustav Sarkar
- Department of Biotechnology, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu 603203, India.
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2
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Alipoor SD, Elieh-Ali-Komi D. Significance of extracellular vesicles in orchestration of immune responses in Mycobacterium tuberculosis infection. Front Cell Infect Microbiol 2024; 14:1398077. [PMID: 38836056 PMCID: PMC11148335 DOI: 10.3389/fcimb.2024.1398077] [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: 03/08/2024] [Accepted: 04/19/2024] [Indexed: 06/06/2024] Open
Abstract
Mycobacterium tuberculosis (M.tb), the causative agent of Tuberculosis, is an intracellular bacterium well known for its ability to subvert host energy and metabolic pathways to maintain its intracellular survival. For this purpose, the bacteria utilize various mechanisms of which extracellular vehicles (EVs) related mechanisms attracted more attention. EVs are nanosized particles that are released by almost all cell types containing active biomolecules from the cell of origin and can target bioactive pathways in the recipient cells upon uptake. It is hypothesized that M.tb dictates the processes of host EV biogenesis pathways, selectively incorporating its molecules into the host EV to direct immune responses in its favor. During infection with Mtb, both mycobacteria and host cells release EVs. The composition of these EVs varies over time, influenced by the physiological and nutritional state of the host environment. Additionally, different EV populations contribute differently to the pathogenesis of disease at various stages of illness participating in a complex interplay between host cells and pathogens. These interactions ultimately influence immune responses and disease outcomes. However, the precise mechanisms and roles of EVs in pathogenicity and disease outcomes remain to be fully elucidated. In this review, we explored the properties and function of EVs in the context of M.tb infection within the host microenvironment and discussed their capacity as a novel therapeutic strategy to combat tuberculosis.
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Affiliation(s)
- Shamila D. Alipoor
- Division of Inflammation and Infection, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Daniel Elieh-Ali-Komi
- Institute of Allergology, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Fraunhofer Institute for Translational Medicine and Pharmacology (ITMP), Immunology and Allergology, Berlin, Germany
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3
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Veerapandian R, Gadad SS, Jagannath C, Dhandayuthapani S. Live Attenuated Vaccines against Tuberculosis: Targeting the Disruption of Genes Encoding the Secretory Proteins of Mycobacteria. Vaccines (Basel) 2024; 12:530. [PMID: 38793781 PMCID: PMC11126151 DOI: 10.3390/vaccines12050530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Revised: 05/07/2024] [Accepted: 05/08/2024] [Indexed: 05/26/2024] Open
Abstract
Tuberculosis (TB), a chronic infectious disease affecting humans, causes over 1.3 million deaths per year throughout the world. The current preventive vaccine BCG provides protection against childhood TB, but it fails to protect against pulmonary TB. Multiple candidates have been evaluated to either replace or boost the efficacy of the BCG vaccine, including subunit protein, DNA, virus vector-based vaccines, etc., most of which provide only short-term immunity. Several live attenuated vaccines derived from Mycobacterium tuberculosis (Mtb) and BCG have also been developed to induce long-term immunity. Since Mtb mediates its virulence through multiple secreted proteins, these proteins have been targeted to produce attenuated but immunogenic vaccines. In this review, we discuss the characteristics and prospects of live attenuated vaccines generated by targeting the disruption of the genes encoding secretory mycobacterial proteins.
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Affiliation(s)
- Raja Veerapandian
- Center of Emphasis in Infectious Diseases, Department of Molecular and Translational Medicine, Paul L. Foster School of Medicine, Texas Tech University Health Sciences Center El Paso, El Paso, TX 79905, USA
| | - Shrikanth S. Gadad
- Center of Emphasis in Cancer, Department of Molecular and Translational Medicine, Paul L. Foster School of Medicine, Texas Tech University Health Sciences Center El Paso, El Paso, TX 79905, USA
| | - Chinnaswamy Jagannath
- Department of Pathology and Genomic Medicine, Houston Methodist Research Institute & Weill Cornell Medical College, Houston, TX 77030, USA
| | - Subramanian Dhandayuthapani
- Center of Emphasis in Infectious Diseases, Department of Molecular and Translational Medicine, Paul L. Foster School of Medicine, Texas Tech University Health Sciences Center El Paso, El Paso, TX 79905, USA
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4
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Rahlwes KC, Dias BR, Campos PC, Alvarez-Arguedas S, Shiloh MU. Pathogenicity and virulence of Mycobacterium tuberculosis. Virulence 2023; 14:2150449. [PMID: 36419223 PMCID: PMC9817126 DOI: 10.1080/21505594.2022.2150449] [Citation(s) in RCA: 32] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis, an infectious disease with one of the highest morbidity and mortality rates worldwide. Leveraging its highly evolved repertoire of non-protein and protein virulence factors, Mtb invades through the airway, subverts host immunity, establishes its survival niche, and ultimately escapes in the setting of active disease to initiate another round of infection in a naive host. In this review, we will provide a concise synopsis of the infectious life cycle of Mtb and its clinical and epidemiologic significance. We will also take stock of its virulence factors and pathogenic mechanisms that modulate host immunity and facilitate its spread. Developing a greater understanding of the interface between Mtb virulence factors and host defences will enable progress toward improved vaccines and therapeutics to prevent and treat tuberculosis.
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Affiliation(s)
- Kathryn C. Rahlwes
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Beatriz R.S. Dias
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Priscila C. Campos
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Samuel Alvarez-Arguedas
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Michael U. Shiloh
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA,Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX, USA,CONTACT Michael U. Shiloh
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5
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Bigi MM, Forrellad MA, García JS, Blanco FC, Vázquez CL, Bigi F. An update on Mycobacterium tuberculosis lipoproteins. Future Microbiol 2023; 18:1381-1398. [PMID: 37962486 DOI: 10.2217/fmb-2023-0088] [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: 04/17/2023] [Accepted: 08/29/2023] [Indexed: 11/15/2023] Open
Abstract
Almost 3% of the proteins of Mycobacterium tuberculosis (M. tuberculosis), the main causative agent of human tuberculosis, are lipoproteins. These lipoproteins are characteristic of the mycobacterial cell envelope and participate in many mechanisms involved in the pathogenesis of M. tuberculosis. In this review, the authors provide an updated analysis of M. tuberculosis lipoproteins and categorize them according to their demonstrated or predicted functions, including transport of compounds to and from the cytoplasm, biosynthesis of the mycobacterial cell envelope, defense and resistance mechanisms, enzymatic activities and signaling pathways. In addition, this updated analysis revealed that at least 40% of M. tuberculosis lipoproteins are glycosylated.
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Affiliation(s)
- María M Bigi
- Instituto de Investigaciones Biomédicas, CONICET, Universidad de Buenos Aires, Paraguay 2155 (C1121ABG), Buenos Aires, Argentina
| | - Marina A Forrellad
- Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria, Argentina (INTA), N. Repetto & de los Reseros, Hurlingham (1686), Buenos Aires, Argentina
- Instituto de Agrobiotecnología y Biología Molecular, INTA-CONICET, N. Repetto & de los Reseros, Hurlingham (1686), Buenos Aires, Argentina
| | - Julia S García
- Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria, Argentina (INTA), N. Repetto & de los Reseros, Hurlingham (1686), Buenos Aires, Argentina
- Instituto de Agrobiotecnología y Biología Molecular, INTA-CONICET, N. Repetto & de los Reseros, Hurlingham (1686), Buenos Aires, Argentina
| | - Federico C Blanco
- Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria, Argentina (INTA), N. Repetto & de los Reseros, Hurlingham (1686), Buenos Aires, Argentina
- Instituto de Agrobiotecnología y Biología Molecular, INTA-CONICET, N. Repetto & de los Reseros, Hurlingham (1686), Buenos Aires, Argentina
| | - Cristina L Vázquez
- Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria, Argentina (INTA), N. Repetto & de los Reseros, Hurlingham (1686), Buenos Aires, Argentina
- Instituto de Agrobiotecnología y Biología Molecular, INTA-CONICET, N. Repetto & de los Reseros, Hurlingham (1686), Buenos Aires, Argentina
| | - Fabiana Bigi
- Instituto de Biotecnología, CICVyA, Instituto Nacional de Tecnología Agropecuaria, Argentina (INTA), N. Repetto & de los Reseros, Hurlingham (1686), Buenos Aires, Argentina
- Instituto de Agrobiotecnología y Biología Molecular, INTA-CONICET, N. Repetto & de los Reseros, Hurlingham (1686), Buenos Aires, Argentina
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6
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Zihad SNK, Sifat N, Islam MA, Monjur-Al-Hossain A, Sikdar KYK, Sarker MMR, Shilpi JA, Uddin SJ. Role of pattern recognition receptors in sensing Mycobacterium tuberculosis. Heliyon 2023; 9:e20636. [PMID: 37842564 PMCID: PMC10570006 DOI: 10.1016/j.heliyon.2023.e20636] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 09/06/2023] [Accepted: 10/03/2023] [Indexed: 10/17/2023] Open
Abstract
Mycobacterium tuberculosis is one of the major invasive intracellular pathogens causing most deaths by a single infectious agent. The interaction between host immune cells and this pathogen is the focal point of the disease, Tuberculosis. Host immune cells not only mount the protective action against this pathogen but also serve as the primary niche for growth. Thus, recognition of this pathogen by host immune cells and following signaling cascades are key dictators of the disease state. Immune cells, mainly belonging to myeloid cell lineage, recognize a wide variety of Mycobacterium tuberculosis ligands ranging from carbohydrate and lipids to proteins to nucleic acids by different membrane-bound and soluble pattern recognition receptors. Simultaneous interaction between different host receptors and pathogen ligands leads to immune-inflammatory response as well as contributes to virulence. This review summarizes the contribution of pattern recognition receptors of host immune cells in recognizing Mycobacterium tuberculosis and subsequent initiation of signaling pathways to provide the molecular insight of the specific Mtb ligands interacting with specific PRR, key adaptor molecules of the downstream signaling pathways and the resultant effector functions which will aid in identifying novel drug targets, and developing novel drugs and adjuvants.
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Affiliation(s)
| | - Nazifa Sifat
- Department of Pharmacy, ASA University of Bangladesh, Dhaka, 1207, Bangladesh
| | | | | | | | - Md Moklesur Rahman Sarker
- Department of Pharmacy, State University of Bangladesh, Dhaka, 1205, Bangladesh
- Department of Pharmacy, Gono University, Nolam, Mirzanagar, Savar, Dhaka 1344, Bangladesh
| | - Jamil A. Shilpi
- Pharmacy Discipline, Life Science School, Khulna University, Khulna, 9208, Bangladesh
| | - Shaikh Jamal Uddin
- Pharmacy Discipline, Life Science School, Khulna University, Khulna, 9208, Bangladesh
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7
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Krishnan V, Nath S, Nair P, Das B. Mycobacterium tuberculosis and its clever approaches to escape the deadly macrophage. World J Microbiol Biotechnol 2023; 39:300. [PMID: 37667129 DOI: 10.1007/s11274-023-03735-9] [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: 06/21/2023] [Accepted: 08/19/2023] [Indexed: 09/06/2023]
Abstract
Mycobacterium tuberculosis (Mt.b), a deadly disease causer, is a facultative parasite. This microorganism has developed several methods to defend itself, once internalized within specialised vacuoles in the macrophages. A wide array of receptors like the complement receptor mannose receptors, scavenger receptor assists the entry of the microbe within the phagocytic macrophages. However, Mt.b is clever enough to protect itself from the hostile environment of the macrophage thereby prevailing within it. The microbe can efficiently inhibit processes like phagosome-lysosome fusion, acidification of phagosomes, release of proinflammatory cytokines and stop crucial events like apoptosis. Additionally, it also adopts resistance to killing by reactive oxygen intermediates and reactive nitrogen intermediates. There are multiple genes both in host and the pathogen which are involved in this successful survival of Mt.b. The regulation of phagolysosome fusion is mediated by proteins such as Coronin, TlyA, SapM, PnkG, EsxH. The microbe has certain mechanisms to even acquire iron from the host cell, to withstand iron deprivation as a mode of host's defence mechanism. This review focuses on the various defensive adaptations acquired by Mt.b for fighting against the deprived conditions existing within the macrophages and their capability of proliferating successfully within it, thereby resulting in a diseased condition.
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Affiliation(s)
- Vinaya Krishnan
- Department of Biotechnology, Mount Carmel College Autonomous, Bengaluru, 560052, India
| | | | - Preetha Nair
- Department of Biotechnology, Mount Carmel College Autonomous, Bengaluru, 560052, India
| | - Bannhi Das
- Department of Biotechnology, Mount Carmel College Autonomous, Bengaluru, 560052, India.
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8
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Ramon-Luing LA, Palacios Y, Ruiz A, Téllez-Navarrete NA, Chavez-Galan L. Virulence Factors of Mycobacterium tuberculosis as Modulators of Cell Death Mechanisms. Pathogens 2023; 12:839. [PMID: 37375529 DOI: 10.3390/pathogens12060839] [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: 05/02/2023] [Revised: 05/29/2023] [Accepted: 06/16/2023] [Indexed: 06/29/2023] Open
Abstract
Mycobacterium tuberculosis (Mtb) modulates diverse cell death pathways to escape the host immune responses and favor its dissemination, a complex process of interest in pathogenesis-related studies. The main virulence factors of Mtb that alter cell death pathways are classified according to their origin as either non-protein (for instance, lipomannan) or protein (such as the PE family and ESX secretion system). The 38 kDa lipoprotein, ESAT-6 (early antigen-secreted protein 6 kDa), and another secreted protein, tuberculosis necrotizing toxin (TNT), induces necroptosis, thereby allowing mycobacteria to survive inside the cell. The inhibition of pyroptosis by blocking inflammasome activation by Zmp1 and PknF is another pathway that aids the intracellular replication of Mtb. Autophagy inhibition is another mechanism that allows Mtb to escape the immune response. The enhanced intracellular survival (Eis) protein, other proteins, such as ESX-1, SecA2, SapM, PE6, and certain microRNAs, also facilitate Mtb host immune escape process. In summary, Mtb affects the microenvironment of cell death to avoid an effective immune response and facilitate its spread. A thorough study of these pathways would help identify therapeutic targets to prevent the survival of mycobacteria in the host.
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Affiliation(s)
- Lucero A Ramon-Luing
- Laboratory of Integrative Immunology, Instituto Nacional de Enfermedades Respiratorias "Ismael Cosío Villegas", Mexico City 14080, Mexico
| | - Yadira Palacios
- Escuela Militar de Graduados de Sanidad, Secretaría de la Defensa Nacional, Mexico City 11200, Mexico
- Department of Biological Systems, Universidad Autónoma Metropolitana, Campus Xochimilco, Mexico City 04960, Mexico
| | - Andy Ruiz
- Laboratory of Integrative Immunology, Instituto Nacional de Enfermedades Respiratorias "Ismael Cosío Villegas", Mexico City 14080, Mexico
| | - Norma A Téllez-Navarrete
- Department of Healthcare Coordination, Instituto Nacional de Enfermedades Respiratorias "Ismael Cosío Villegas", Mexico City 14080, Mexico
| | - Leslie Chavez-Galan
- Laboratory of Integrative Immunology, Instituto Nacional de Enfermedades Respiratorias "Ismael Cosío Villegas", Mexico City 14080, Mexico
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9
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Witt KD. Role of MHC class I pathways in Mycobacterium tuberculosis antigen presentation. Front Cell Infect Microbiol 2023; 13:1107884. [PMID: 37009503 PMCID: PMC10050577 DOI: 10.3389/fcimb.2023.1107884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 02/23/2023] [Indexed: 03/17/2023] Open
Abstract
MHC class I antigen processing is an underappreciated area of nonviral host–pathogen interactions, bridging both immunology and cell biology, where the pathogen’s natural life cycle involves little presence in the cytoplasm. The effective response to MHC-I foreign antigen presentation is not only cell death but also phenotypic changes in other cells and stimulation of the memory cells ready for the next antigen reoccurrence. This review looks at the MHC-I antigen processing pathway and potential alternative sources of the antigens, focusing on Mycobacterium tuberculosis (Mtb) as an intracellular pathogen that co-evolved with humans and developed an array of decoy strategies to survive in a hostile environment by manipulating host immunity to its own advantage. As that happens via the selective antigen presentation process, reinforcement of the effective antigen recognition on MHC-I molecules may stimulate subsets of effector cells that act earlier and more locally. Vaccines against tuberculosis (TB) could potentially eliminate this disease, yet their development has been slow, and success is limited in the context of this global disease’s spread. This review’s conclusions set out potential directions for MHC-I-focused approaches for the next generation of vaccines.
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Affiliation(s)
- Karolina D. Witt
- Pandemic Sciences Institute, University of Oxford, Oxford, United Kingdom
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- *Correspondence: Karolina D. Witt,
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10
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Singh S, Maurya SK, Aqdas M, Bashir H, Arora A, Bhalla V, Agrewala JN. Mycobacterium tuberculosis exploits MPT64 to generate myeloid-derived suppressor cells to evade the immune system. Cell Mol Life Sci 2022; 79:567. [DOI: 10.1007/s00018-022-04596-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 09/19/2022] [Accepted: 10/09/2022] [Indexed: 11/24/2022]
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11
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Pattanaik KP, Sengupta S, Jit BP, Kotak R, Sonawane A. Host-Mycobacteria conflict: Immune responses of the host vs. the mycobacteria TLR2 and TLR4 ligands and concomitant host-directed therapy. Microbiol Res 2022; 264:127153. [DOI: 10.1016/j.micres.2022.127153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 07/21/2022] [Accepted: 07/29/2022] [Indexed: 12/15/2022]
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12
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Mycobacterium tuberculosis PPE51 Inhibits Autophagy by Suppressing Toll-Like Receptor 2-Dependent Signaling. mBio 2022; 13:e0297421. [PMID: 35467412 PMCID: PMC9239179 DOI: 10.1128/mbio.02974-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Autophagy is an ubiquitous homeostatic pathway in mammalian cells and plays a significant role in host immunity. Substantial evidence indicates that the ability of Mycobacterium tuberculosis (Mtb) to successfully evade immune responses is partially due to inhibition of autophagic pathways. Our previous screening of Mtb transposon mutants identified the PPE51 protein as an important autophagy-inhibiting effector. We found that expression of PPE51, either by infecting bacteria or by direct expression in host cells, suppressed responses to potent autophagy-inducing stimuli and interfered with bacterial phagocytosis. This phenotype was associated with reduced activation of extracellular signal-regulated kinase 1/2 (ERK1/2), a key component of signaling pathways that stimulate autophagy. Multiple lines of evidence demonstrated that the effects of PPE51 are attributable to signal blocking by Toll-like receptor 2 (TLR2), a receptor with known involvement of activation of ERK1/2 and autophagy. Consistent with these results, mice with intact TLR2 signaling showed striking virulence attenuation for an Mtb ppe51 deletion mutant (Δ51) compared to wild-type Mtb, whereas infection of TLR2-deficient mice showed no such attenuation. Mice infected with Δ51 also displayed increased T cell responses to Mtb antigens and increased autophagy in infected lung tissues. Together, these results suggest that TLR2 activates relevant host immune functions during mycobacterial infection, which Mtb then evades through suppression of TLR2 signaling by PPE51. In addition to its previously identified function transporting substrates across the bacterial cell wall, our results demonstrate a direct role of PPE51 for evasion of both innate and adaptive immunity to Mtb.
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13
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Jiang S, Redelman-Sidi G. BCG in Bladder Cancer Immunotherapy. Cancers (Basel) 2022; 14:3073. [PMID: 35804844 PMCID: PMC9264881 DOI: 10.3390/cancers14133073] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 06/20/2022] [Accepted: 06/20/2022] [Indexed: 01/18/2023] Open
Abstract
BCG is a live attenuated strain of Mycobacterium bovis that is primarily used as a vaccine against tuberculosis. In the past four decades, BCG has also been used for the treatment of non-muscle invasive bladder cancer (NMIBC). In patients with NMIBC, BCG reduces the risk of tumor recurrence and decreases the likelihood of progression to more invasive disease. Despite the long-term clinical experience with BCG, its mechanism of action is still being elucidated. Data from animal models and from human studies suggests that BCG activates both the innate and adaptive arms of the immune system eventually leading to tumor destruction. Herein, we review the current data regarding the mechanism of BCG and summarize the evidence for its clinical efficacy and recommended indications and clinical practice.
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Affiliation(s)
- Song Jiang
- Urology Service, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA;
| | - Gil Redelman-Sidi
- Infectious Diseases Service, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
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14
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High-resolution crystal structure of LpqH, an immunomodulatory surface lipoprotein of Mycobacterium tuberculosis reveals a distinct fold and a conserved cleft on its surface. Int J Biol Macromol 2022; 210:494-503. [PMID: 35504420 DOI: 10.1016/j.ijbiomac.2022.04.196] [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: 12/06/2021] [Revised: 04/07/2022] [Accepted: 04/26/2022] [Indexed: 11/22/2022]
Abstract
Tuberculosis, caused by Mycobacterium tuberculosis, is predominantly a disease of the lungs acquired by inhaling mycobacteria from infected individuals via airborne droplets. In order to facilitate their entry into the alveolar macrophages, mycobacteria have a collection of pathogen-associated molecular patterns (PAMPs) on their surface that are known to detect certain pattern recognition receptors present on the surface of host cells. A major group of these PAMPs includes mycobacterial lipoproteins, of which, the 19 kDa surface antigen LpqH, has been reported to play a critical role in both host-pathogen interactions as well as pleiotropic immune regulation. Despite its crucial involvement in tuberculosis, the detailed structure-function relationship of this protein remains to be explored. Here, we report the high-resolution crystal structure of the non-acylated LpqH (LpqH48-159) at a resolution of 1.26 Å, which adopts a unique fold. Flow cytometry-based experiments show that the protein can bind and induce apoptosis in PMA-activated human monocytic cell line THP-1, indicative of the preservation of functionality of the protein. Furthermore, analysis of conservation of LpqH sequences from Mycobacterium species reveals a patch of conserved residues on the surface which may play a role in its binding partner recognition and hence in host-pathogen interaction.
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15
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Mehaffy C, Ryan JM, Kruh-Garcia NA, Dobos KM. Extracellular Vesicles in Mycobacteria and Tuberculosis. Front Cell Infect Microbiol 2022; 12:912831. [PMID: 35719351 PMCID: PMC9204639 DOI: 10.3389/fcimb.2022.912831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 04/27/2022] [Indexed: 11/13/2022] Open
Abstract
Tuberculosis (TB) remains a public health issue causing millions of infections every year. Of these, about 15% ultimately result in death. Efforts to control TB include development of new and more effective vaccines, novel and more effective drug treatments, and new diagnostics that test for both latent TB Infection and TB disease. All of these areas of research benefit from a good understanding of the physiology of Mycobacterium tuberculosis (Mtb), the primary causative agent of TB. Mtb secreted protein antigens have been the focus of vaccine and diagnosis research for the past century. Recently, the discovery of extracellular vesicles (EVs) as an important source of secreted antigens in Mtb has gained attention. Similarly, the discovery that host EVs can carry Mtb products during in vitro and in vivo infection has spiked interest because of its potential use in blood-based diagnostics. Despite advances in understanding the content of Mtb and Mtb-infected host extracellular vesicles, our understanding on the biogenesis and role of Mtb and host extracellular vesicles during Mtb infection is still nascent. Here, we explore the current literature on extracellular vesicles regarding Mtb, discuss the host and Mtb extracellular vesicles as distinct entities, and discuss current gaps in the field.
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Millar CL, Anto L, Garcia C, Kim MB, Jain A, Provatas AA, Clark RB, Lee JY, Nichols FC, Blesso CN. Gut Microbiome-Derived Glycine Lipids Are Diet-Dependent Modulators of Hepatic Injury and Atherosclerosis. J Lipid Res 2022; 63:100192. [PMID: 35278409 PMCID: PMC9020096 DOI: 10.1016/j.jlr.2022.100192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 02/12/2022] [Accepted: 03/03/2022] [Indexed: 02/06/2023] Open
Abstract
Oral and gut Bacteroidetes produce unique classes of serine-glycine lipodipeptides and glycine aminolipids that signal through host Toll-like receptor 2. These glycine lipids have also been detected in human arteries, but their effects on atherosclerosis are unknown. Here, we sought to investigate the bioactivity of bacterial glycine lipids in mouse models of atherosclerosis. Lipid 654 (L654), a serine-glycine lipodipeptide species, was first tested in a high-fat diet (HFD)-fed Ldlr−/− model of atherosclerosis. Intraperitoneal administration of L654 over 7 weeks to HFD-fed Ldlr−/− mice resulted in hypocholesterolemic effects and significantly attenuated the progression of atherosclerosis. We found that L654 also reduced liver inflammatory and extracellular matrix gene expression, which may be related to inhibition of macrophage activation as demonstrated in vivo by lower major histocompatibility complex class II gene expression and confirmed in cell experiments. In addition, L654 and other bacterial glycine lipids in feces, liver, and serum were markedly reduced alongside changes in Bacteroidetes relative abundance in HFD-fed mice. Finally, we tested the bioactivities of L654 and related lipid 567 in chow-fed Apoe−/− mice, which displayed much higher fecal glycine lipids relative to HFD-fed Ldlr−/− mice. Administration of L654 or lipid 567 for 7 weeks to these mice reduced the liver injury marker alanine aminotransferase, but other effects seen in Ldlr−/− were not observed. Therefore, we conclude that conditions in which gut microbiome-derived glycine lipids are lost, such as HFD, may exacerbate the development of atherosclerosis and liver injury, whereas correction of such depletion may protect from these disorders.
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Affiliation(s)
- Courtney L Millar
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT, USA; The Marcus Institute for Aging Research, Harvard Medical School, Boston, MA, USA
| | - Liya Anto
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT, USA
| | - Chelsea Garcia
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT, USA
| | - Mi-Bo Kim
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT, USA
| | - Anisha Jain
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT, USA
| | - Anthony A Provatas
- Center for Environmental Sciences and Engineering, University of Connecticut, Storrs, CT, USA
| | - Robert B Clark
- Department of Immunology, UConn Health, Farmington, CT, USA; Department of Medicine, UConn Health, Farmington, CT, USA
| | - Ji-Young Lee
- Department of Nutritional Sciences, University of Connecticut, Storrs, CT, USA
| | - Frank C Nichols
- Department of Periodontology, UConn Health, Farmington, CT, USA
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17
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Categorizing sequences of concern by function to better assess mechanisms of microbial pathogenesis. Infect Immun 2021; 90:e0033421. [PMID: 34780277 PMCID: PMC9119117 DOI: 10.1128/iai.00334-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
To identify sequences with a role in microbial pathogenesis, we assessed the adequacy of their annotation by existing controlled vocabularies and sequence databases. Our goal was to regularize descriptions of microbial pathogenesis for improved integration with bioinformatic applications. Here, we review the challenges of annotating sequences for pathogenic activity. We relate the categorization of more than 2,750 sequences of pathogenic microbes through a controlled vocabulary called Functions of Sequences of Concern (FunSoCs). These allow for an ease of description by both humans and machines. We provide a subset of 220 fully annotated sequences in the supplemental material as examples. The use of this compact (∼30 terms), controlled vocabulary has potential benefits for research in microbial genomics, public health, biosecurity, biosurveillance, and the characterization of new and emerging pathogens.
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18
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Enriquez AB, Izzo A, Miller SM, Stewart EL, Mahon RN, Frank DJ, Evans JT, Rengarajan J, Triccas JA. Advancing Adjuvants for Mycobacterium tuberculosis Therapeutics. Front Immunol 2021; 12:740117. [PMID: 34759923 PMCID: PMC8572789 DOI: 10.3389/fimmu.2021.740117] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 08/26/2021] [Indexed: 01/15/2023] Open
Abstract
Tuberculosis (TB) remains one of the leading causes of death worldwide due to a single infectious disease agent. BCG, the only licensed vaccine against TB, offers limited protection against pulmonary disease in children and adults. TB vaccine research has recently been reinvigorated by new data suggesting alternative administration of BCG induces protection and a subunit/adjuvant vaccine that provides close to 50% protection. These results demonstrate the need for generating adjuvants in order to develop the next generation of TB vaccines. However, development of TB-targeted adjuvants is lacking. To help meet this need, NIAID convened a workshop in 2020 titled “Advancing Vaccine Adjuvants for Mycobacterium tuberculosis Therapeutics”. In this review, we present the four areas identified in the workshop as necessary for advancing TB adjuvants: 1) correlates of protective immunity, 2) targeting specific immune cells, 3) immune evasion mechanisms, and 4) animal models. We will discuss each of these four areas in detail and summarize what is known and what we can advance on in order to help develop more efficacious TB vaccines.
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Affiliation(s)
- Ana B Enriquez
- Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, United States.,Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States
| | - Angelo Izzo
- Tuberculosis Research Program, Centenary Institute, The University of Sydney, Sydney, NSW, Australia
| | - Shannon M Miller
- Center for Translational Medicine, University of Montana, Missoula, MT, United States.,Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT, United States
| | - Erica L Stewart
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,Sydney Institute for Infectious Diseases and Charles Perkins Centre, The University of Sydney, Sydney, NSW, Australia
| | - Robert N Mahon
- Division of AIDS, Columbus Technologies & Services Inc., Contractor to National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Daniel J Frank
- Division of AIDS, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, United States
| | - Jay T Evans
- Center for Translational Medicine, University of Montana, Missoula, MT, United States.,Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT, United States
| | - Jyothi Rengarajan
- Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, United States.,Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States.,Department of Medicine, Division of Infectious Diseases, Emory University School of Medicine, Atlanta, GA, United States
| | - James A Triccas
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,Sydney Institute for Infectious Diseases and Charles Perkins Centre, The University of Sydney, Sydney, NSW, Australia
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19
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Hinman AE, Jani C, Pringle SC, Zhang WR, Jain N, Martinot AJ, Barczak AK. Mycobacterium tuberculosis canonical virulence factors interfere with a late component of the TLR2 response. eLife 2021; 10:e73984. [PMID: 34755600 PMCID: PMC8610422 DOI: 10.7554/elife.73984] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 10/29/2021] [Indexed: 01/15/2023] Open
Abstract
For many intracellular pathogens, the phagosome is the site of events and interactions that shape infection outcome. Phagosomal membrane damage, in particular, is proposed to benefit invading pathogens. To define the innate immune consequences of this damage, we profiled macrophage transcriptional responses to wild-type Mycobacterium tuberculosis (Mtb) and mutants that fail to damage the phagosomal membrane. We identified a set of genes with enhanced expression in response to the mutants. These genes represented a late component of the TLR2-dependent transcriptional response to Mtb, distinct from an earlier component that included Tnf. Expression of the later component was inherent to TLR2 activation, dependent upon endosomal uptake, and enhanced by phagosome acidification. Canonical Mtb virulence factors that contribute to phagosomal membrane damage blunted phagosome acidification and undermined the endosome-specific response. Profiling cell survival and bacterial growth in macrophages demonstrated that the attenuation of these mutants is partially dependent upon TLR2. Further, TLR2 contributed to the attenuated phenotype of one of these mutants in a murine model of infection. These results demonstrate two distinct components of the TLR2 response and identify a component dependent upon endosomal uptake as a point where pathogenic bacteria interfere with the generation of effective inflammation. This interference promotes tuberculosis (TB) pathogenesis in both macrophage and murine infection models.
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Affiliation(s)
- Amelia E Hinman
- The Ragon Institute, Massachusetts General HospitalCambridgeUnited States
| | - Charul Jani
- The Ragon Institute, Massachusetts General HospitalCambridgeUnited States
| | | | - Wei R Zhang
- The Ragon Institute, Massachusetts General HospitalCambridgeUnited States
| | - Neharika Jain
- Department of Infectious Diseases and Global Health, Tufts University Cummings School of Veterinary MedicineNorth Grafton, MAUnited States
| | - Amanda J Martinot
- Department of Infectious Diseases and Global Health, Tufts University Cummings School of Veterinary MedicineNorth Grafton, MAUnited States
| | - Amy K Barczak
- The Ragon Institute, Massachusetts General HospitalCambridgeUnited States
- The Division of Infectious Diseases, Massachusetts General HospitalBostonUnited States
- Department of Medicine, Harvard Medical SchoolBostonUnited States
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20
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Venkataranganayaka Abhilasha K, Kedihithlu Marathe G. Bacterial lipoproteins in sepsis. Immunobiology 2021; 226:152128. [PMID: 34488139 DOI: 10.1016/j.imbio.2021.152128] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 07/09/2021] [Accepted: 08/10/2021] [Indexed: 01/05/2023]
Abstract
Bacterial lipoproteins are membrane proteins derived from both gram-negative and gram-positive bacteria. They seem to have diverse functions not only on bacterial growth, but also play an important role in host's virulence. Bacterial lipoproteins exert their action on host immune cells via TLR2/1 or TLR2/6. Therefore, bacterial lipoproteins also need to be considered while addressing bacterial pathogenicity besides classical bacterial endotoxin like LPS and other microbial associated molecular patterns such as LTA, and peptidoglycans. In this mini-review, we provide an overview of general bacterial lipoprotein biosynthesis and the need to understand the lipoprotein-mediated pathogenicity in diseases like sepsis.
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Affiliation(s)
- Kandahalli Venkataranganayaka Abhilasha
- Department of Studies in Biochemistry, University of Mysore, Manasagangothri, Mysuru 570006, Karnataka, India; Cancer and Developmental Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Gopal Kedihithlu Marathe
- Department of Studies in Biochemistry, University of Mysore, Manasagangothri, Mysuru 570006, Karnataka, India; Department of Studies in Molecular Biology, University of Mysore, Manasagangothri, Mysuru 570006, Karnataka, India.
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21
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Nontuberculous Mycobacteria, Macrophages, and Host Innate Immune Response. Infect Immun 2021; 89:e0081220. [PMID: 34097459 DOI: 10.1128/iai.00812-20] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Although nontuberculous mycobacteria (NTM) are considered opportunistic infections, incidence and prevalence of NTM infection are increasing worldwide becoming a major public health threat. Innate immunity plays an essential role in mediating the initial host response against these intracellular bacteria. Specifically, macrophages phagocytose and eliminate NTM and act as antigen-presenting cells, which trigger downstream activation of cellular and humoral adaptive immune responses. Identification of macrophage receptors, mycobacterial ligands, phagosome maturation, autophagy/necrosis, and escape mechanisms are important components of this immunity network. The role of the macrophage in mycobacterial disease has mainly been studied in tuberculosis (TB), but limited information exists on its role in NTM. In this review, we focus on NTM immunity, the role of macrophages, and host interaction in NTM infection.
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22
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Jia L, Sha S, Yang S, Taj A, Ma Y. Effect of Protein O-Mannosyltransferase (MSMEG_5447) on M. smegmatis and Its Survival in Macrophages. Front Microbiol 2021; 12:657726. [PMID: 34276591 PMCID: PMC8278756 DOI: 10.3389/fmicb.2021.657726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Accepted: 05/31/2021] [Indexed: 12/12/2022] Open
Abstract
Protein O-mannosyltransferase (PMT) catalyzes an initial step of protein O-mannosylation of Mycobacterium tuberculosis (Mtb) and plays a crucial role for Mtb survival in the host. To better understand the role of PMT in the host innate immune response during mycobacterial infection, in this study, we utilized Mycobacterium smegmatis pmt (MSMEG_5447) gene knockout strain, ΔM5447, to infect THP-1 cells. Our results revealed that the lack of MSMEG_5447 not only impaired the growth of M. smegmatis in 7H9 medium but also reduced the resistance of M. smegmatis against lysozyme and acidic stress in vitro. Macrophage infection assay showed that ΔM5447 displayed attenuated growth in macrophages at 24 h post-infection. The production of TNF-α and IL-6 and the activation of transcription factor NF-κB were decreased in ΔM5447-infected macrophages, which were further confirmed by transcriptomic analysis. Moreover, ΔM5447 failed to inhibit phagosome–lysosome fusion in macrophages. These findings revealed that PMT played a role in modulating the innate immune responses of the host, which broaden our understanding for functions of protein O-mannosylation in mycobacterium–host interaction.
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Affiliation(s)
- Liqiu Jia
- Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Dalian Medical University, Dalian, China
| | - Shanshan Sha
- Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Dalian Medical University, Dalian, China
| | - Shufeng Yang
- Department of Microbiology, College of Basic Medical Sciences, Dalian Medical University, Dalian, China
| | - Ayaz Taj
- Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Dalian Medical University, Dalian, China
| | - Yufang Ma
- Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Dalian Medical University, Dalian, China.,Department of Microbiology, College of Basic Medical Sciences, Dalian Medical University, Dalian, China
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23
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Dubé JY, Fava VM, Schurr E, Behr MA. Underwhelming or Misunderstood? Genetic Variability of Pattern Recognition Receptors in Immune Responses and Resistance to Mycobacterium tuberculosis. Front Immunol 2021; 12:714808. [PMID: 34276708 PMCID: PMC8278570 DOI: 10.3389/fimmu.2021.714808] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 06/17/2021] [Indexed: 12/23/2022] Open
Abstract
Human genetic control is thought to affect a considerable part of the outcome of infection with Mycobacterium tuberculosis (Mtb). Most of us deal with the pathogen by containment (associated with clinical "latency") or sterilization, but tragically millions each year do not. After decades of studies on host genetic susceptibility to Mtb infection, genetic variation has been discovered to play a role in tuberculous immunoreactivity and tuberculosis (TB) disease. Genes encoding pattern recognition receptors (PRRs) enable a consistent, molecularly direct interaction between humans and Mtb which suggests the potential for co-evolution. In this review, we explore the roles ascribed to PRRs during Mtb infection and ask whether such a longstanding and intimate interface between our immune system and this pathogen plays a critical role in determining the outcome of Mtb infection. The scientific evidence to date suggests that PRR variation is clearly implicated in altered immunity to Mtb but has a more subtle role in limiting the pathogen and pathogenesis. In contrast to 'effectors' like IFN-γ, IL-12, Nitric Oxide and TNF that are critical for Mtb control, 'sensors' like PRRs are less critical for the outcome of Mtb infection. This is potentially due to redundancy of the numerous PRRs in the innate arsenal, such that Mtb rarely goes unnoticed. Genetic association studies investigating PRRs during Mtb infection should therefore be designed to investigate endophenotypes of infection - such as immunological or clinical variation - rather than just TB disease, if we hope to understand the molecular interface between innate immunity and Mtb.
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Affiliation(s)
- Jean-Yves Dubé
- Department of Microbiology and Immunology, McGill University, Montreal, QC, Canada
- Program in Infectious Diseases and Immunity in Global Health, The Research Institute of the McGill University Health Centre, Montreal, QC, Canada
- McGill International TB Centre, McGill University, Montreal, QC, Canada
| | - Vinicius M. Fava
- Program in Infectious Diseases and Immunity in Global Health, The Research Institute of the McGill University Health Centre, Montreal, QC, Canada
- McGill International TB Centre, McGill University, Montreal, QC, Canada
| | - Erwin Schurr
- Department of Microbiology and Immunology, McGill University, Montreal, QC, Canada
- Program in Infectious Diseases and Immunity in Global Health, The Research Institute of the McGill University Health Centre, Montreal, QC, Canada
- McGill International TB Centre, McGill University, Montreal, QC, Canada
- Department of Human Genetics, Faculty of Medicine, McGill University, Montreal, QC, Canada
- Department of Medicine, Faculty of Medicine, McGill University, Montreal, QC, Canada
| | - Marcel A. Behr
- Department of Microbiology and Immunology, McGill University, Montreal, QC, Canada
- Program in Infectious Diseases and Immunity in Global Health, The Research Institute of the McGill University Health Centre, Montreal, QC, Canada
- McGill International TB Centre, McGill University, Montreal, QC, Canada
- Department of Medicine, Faculty of Medicine, McGill University, Montreal, QC, Canada
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24
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Effect of the deletion of lprG and p55 genes in the K10 strain of Mycobacterium avium subspecies paratuberculosis. Res Vet Sci 2021; 138:1-10. [PMID: 34087563 DOI: 10.1016/j.rvsc.2021.05.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 04/23/2021] [Accepted: 05/25/2021] [Indexed: 11/21/2022]
Abstract
The lprG-p55 operon of Mycobacterium tuberculosis, M. bovis and M. avium strain D4ER has been identified as a virulence factor involved in the transport of toxic compounds. LprG is a lipoprotein that modulates the host immune response against mycobacteria, whereas P55 is an efflux pump that provides resistance to several drugs. In the present study we search for, and characterize, lprg and p55, putative virulence genes in Mycobacterium avium subsp. paratuberculosis (MAP) to generate a live-attenuated strain of MAP that may be useful in the future as live-attenuated vaccine. For this purpose, we generated and evaluated two mutants of MAP strain K10: one mutant lacking the lprG gene (ΔlprG) and the other lacking both genes lprG and p55 (ΔlprG-p55). None of the mutant strains showed altered susceptibility to first-line and second-line antituberculosis drugs or ethidium bromide, only the double mutant had two-fold increase in clarithromycin susceptibility compared with the wild-type strain. The deletion of lprG and of lprG-p55 reduced the replication of MAP in bovine macrophages; however, only the mutant in lprG-p55 grew faster in liquid media and showed reduced viability in macrophages and in a mouse model. Considering that the deletion of both genes lprG-p55, but not that of lprG alone, showed a reduced replication in vivo, we can speculate that p55 contributes to the survival of MAP in this animal model.
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25
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TLRs in Mycobacterial Pathogenesis: Black and White or Shades of Gray. Curr Microbiol 2021; 78:2183-2193. [PMID: 33844035 DOI: 10.1007/s00284-021-02488-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 04/01/2021] [Indexed: 12/19/2022]
Abstract
Toll-like receptors (TLRs) play critical role in the innate recognition of pathogens besides orchestrating innate and adaptive immune responses. These receptors exhibit exquisite specificity for different pathogens or their products and, through a complex network of signalling, generate appropriate immune responses. TLRs induce both pro- and anti-inflammatory signals depending on interactions with the adapter molecules thereby impacting the outcome of infection. Hence, TLR signalling ought to be stringently regulated to avoid harmful effects on the host. Mycobacteria express antigens which are sensed by TLRs leading to activation of various signalling molecules important for initiating the death of infected cells and containment of pathogens. Conversely, it also utilizes TLRs for immune evasion and persistence. Due to the enormous diversity in the repertoire of virulence traits expressed by mycobacteria, genetic variations in TLRs often impair the host's ability to respond to mycobacterial-stress, affecting health and disease manifestations. Thus, understanding TLR signalling is of great importance for insights into host-mycobacterial interactions and designing effective measures for controlling the spread and persistence of the bacterium.
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26
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Park C, Lee MS, Baek JH, Cho SH, Hyun BH, You SH, Cha SH. Intradermal co-inoculation of codon pair deoptimization (CPD)-attenuated chimeric porcine reproductive and respiratory syndrome virus (PRRSV) with Toll like receptor (TLR) agonists enhanced the protective effects in pigs against heterologous challenge. Vet Microbiol 2021; 256:109048. [PMID: 33845333 DOI: 10.1016/j.vetmic.2021.109048] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 03/19/2021] [Indexed: 11/25/2022]
Abstract
The objective of this study was to assess protective efficacy of vaccination using CPD-attenuated chimeric PRRSV and Toll like receptor (TLR) agonists (HSP70 c-terminal domain and HSPX) as adjuvants through different inoculation routes. In this study, a chimeric PRRSV composed of two field isolates was synthesized and attenuated by CPD in NSP1 as described in the previous study. The infection of the CPD-attenuated chimeric PRRSV to pigs of 3 weeks-old showed no clinical signs without pathological lesions in necropsy, while it induced improved cross immunity between its parent strains. The TLR agonists were expressed in E. coli and purified to be used. In challenge experiment, pigs of 3 weeks-old were vaccinated using the CPD-attenuated chimeric virus with the prepared TLR agonists through intramuscular or intradermal route, following heterologous challenge after 4 weeks of vaccination. In results, intramuscular or intradermal inoculation of the CPD-attenuated chimeric virus demonstrated excellent protective efficacy against heterologous challenges. Importantly, intradermal inoculation with the TLR agonists enhanced protective effects as shown in the significantly increased level of PRRSV-specific IFN-γ-SCs and cytokines in sera, and the significant reduction of pathological lesion and viral load in lung. This study suggested that the intradermal inoculation of CPD-attenuated chimeric PRRSV plus TLR agonists should be more effective for protection of pigs against diverse PRRS field viruses.
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Affiliation(s)
- Changhoon Park
- Department of Microbiology and Immunology, Eulji University School of Medicine, Yongdu-dong, Jung-gu, Daejeon, Republic of Korea
| | - Myung-Shin Lee
- Department of Microbiology and Immunology, Eulji University School of Medicine, Yongdu-dong, Jung-gu, Daejeon, Republic of Korea
| | - Jong Hyuk Baek
- Department of Animal Vaccine Development, BioPOA, 593-26 Dongtangiheung-ro, Hwaseong-si, Gyeonggi-do, Republic of Korea
| | - Sun Hee Cho
- Department of Animal Vaccine Development, BioPOA, 593-26 Dongtangiheung-ro, Hwaseong-si, Gyeonggi-do, Republic of Korea
| | - Bang-Hun Hyun
- PRRS Research Laboratory, Viral Diseases Division, Animal and Plant Quarantine Agency, Gimcheon, 39660, Republic of Korea
| | - Su-Hwa You
- PRRS Research Laboratory, Viral Diseases Division, Animal and Plant Quarantine Agency, Gimcheon, 39660, Republic of Korea
| | - Sang-Ho Cha
- PRRS Research Laboratory, Viral Diseases Division, Animal and Plant Quarantine Agency, Gimcheon, 39660, Republic of Korea.
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27
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Allué-Guardia A, García JI, Torrelles JB. Evolution of Drug-Resistant Mycobacterium tuberculosis Strains and Their Adaptation to the Human Lung Environment. Front Microbiol 2021; 12:612675. [PMID: 33613483 PMCID: PMC7889510 DOI: 10.3389/fmicb.2021.612675] [Citation(s) in RCA: 88] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 01/15/2021] [Indexed: 12/12/2022] Open
Abstract
In the last two decades, multi (MDR), extensively (XDR), extremely (XXDR) and total (TDR) drug-resistant Mycobacterium tuberculosis (M.tb) strains have emerged as a threat to public health worldwide, stressing the need to develop new tuberculosis (TB) prevention and treatment strategies. It is estimated that in the next 35 years, drug-resistant TB will kill around 75 million people and cost the global economy $16.7 trillion. Indeed, the COVID-19 pandemic alone may contribute with the development of 6.3 million new TB cases due to lack of resources and enforced confinement in TB endemic areas. Evolution of drug-resistant M.tb depends on numerous factors, such as bacterial fitness, strain's genetic background and its capacity to adapt to the surrounding environment, as well as host-specific and environmental factors. Whole-genome transcriptomics and genome-wide association studies in recent years have shed some insights into the complexity of M.tb drug resistance and have provided a better understanding of its underlying molecular mechanisms. In this review, we will discuss M.tb phenotypic and genotypic changes driving resistance, including changes in cell envelope components, as well as recently described intrinsic and extrinsic factors promoting resistance emergence and transmission. We will further explore how drug-resistant M.tb adapts differently than drug-susceptible strains to the lung environment at the cellular level, modulating M.tb-host interactions and disease outcome, and novel next generation sequencing (NGS) strategies to study drug-resistant TB.
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Affiliation(s)
- Anna Allué-Guardia
- Population Health Program, Tuberculosis Group, Texas Biomedical Research Institute, San Antonio, TX, United States
| | | | - Jordi B. Torrelles
- Population Health Program, Tuberculosis Group, Texas Biomedical Research Institute, San Antonio, TX, United States
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28
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Pattanaik KP, Ganguli G, Naik SK, Sonawane A. Mycobacterium tuberculosis EsxL induces TNF-α secretion through activation of TLR2 dependent MAPK and NF-κB pathways. Mol Immunol 2021; 130:133-141. [PMID: 33419561 DOI: 10.1016/j.molimm.2020.11.020] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 11/06/2020] [Accepted: 11/23/2020] [Indexed: 12/13/2022]
Abstract
Mycobacterium tuberculosis (Mtb) employs distinct strategies to circumvent host immune responses during the infection process. Various Mtb cell-wall associated and secretory proteins are known to play a critical role in the orchestration of host innate immune responses through modulation of signaling pathways. Mtb genome encodes for 23 (EsxA-EsxW) proteins belonging to the ESAT-6 like family; however, most of them are functionally unknown. Here, we show that Mtb EsxL induces tumor necrosis factor-alpha (TNF-α) production by activating nuclear translocation of nuclear factor-κB (NF-κB) via interaction with Toll-like Receptor 2 (TLR2). Blocking or silencing of TLR2 abrogated nuclear translocation of NF-kB and TNF-α production. Treatment with recombinant purified EsxL (rEsxL) activated mitogen-activated protein kinase (MAPK) pathway by inducing the phosphorylation of extracellular signal-regulated kinase (ERK) and p38 kinase (p38) pathways. At the same time, inhibition of ERK and p38 down-regulated the expression of TNF-α in rEsxL exposed murine macrophages. Besides TNF-α, EsxL also induced the production of IL-6 proinflammatory cytokine. Taken together, these results suggest that EsxL is able to induce TNF-α secretion via TLR2 through activation of NF-κB and MAPK signaling. This study will help in deducing therapeutic strategies for better control of the disease.
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Affiliation(s)
| | - Geetanjali Ganguli
- School of Biotechnology, KIIT Deemed to be University, Bhubaneswar, Odisha, India
| | - Sumanta Kumar Naik
- School of Biotechnology, KIIT Deemed to be University, Bhubaneswar, Odisha, India
| | - Avinash Sonawane
- Discipline of Biosciences and Biomedical Engineering, IIT Indore, Madhya Pradesh, India.
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29
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Mohammadzadeh R, Ghazvini K, Farsiani H, Soleimanpour S. Mycobacterium tuberculosis extracellular vesicles: exploitation for vaccine technology and diagnostic methods. Crit Rev Microbiol 2020; 47:13-33. [PMID: 33044878 DOI: 10.1080/1040841x.2020.1830749] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Tuberculosis (TB) is a fatal epidemic disease usually caused by Mycobacterium tuberculosis (Mtb). Pervasive latent infection, multidrug- and extensively drug-resistant tuberculosis (MDR- and XDR-TB), and TB/HIV co-infection make TB a global health problem, which emphasises the design and development of efficient vaccines and diagnostic biomarkers. Extracellular vesicles (EVs) secretion is a conserved phenomenon in all the domains of life. Various cargos such as nucleic acids, toxins, lipoproteins, and enzymes have been recognised in these nano-sized vesicles that may be involved in bacterial physiology and pathogenesis. The intrinsic adjuvant effect, native immunogenic cargo, sensing by host immune cells, circulation in all body fluids, and comprehensive distribution of antigens introduce EVs as a promising tool for designing novel vaccines, diagnostic biomarkers, and drug delivery systems. Genetic engineering of the EV-producing bacteria and the subsequent production of proper EVs could facilitate the development of the EV-based therapeutic applications. Recently, it was demonstrated that thick-walled mycobacteria release EVs, which contain immunodominant cargos such as lipoglycans and lipoproteins. The present article is a comprehensive review on the recent findings of Mtb EVs biology and the exploitation of EVs for the vaccine technology and diagnostic methods.
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Affiliation(s)
- Roghayeh Mohammadzadeh
- Antimicrobial Resistance Research Center, Bu-Ali Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Microbiology and Virology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Kiarash Ghazvini
- Antimicrobial Resistance Research Center, Bu-Ali Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Microbiology and Virology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Hadi Farsiani
- Antimicrobial Resistance Research Center, Bu-Ali Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Microbiology and Virology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Saman Soleimanpour
- Antimicrobial Resistance Research Center, Bu-Ali Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Microbiology and Virology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,Reference Tuberculosis Laboratory, Mashhad University of Medical Sciences, Mashhad, Iran
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30
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Bose S, Aggarwal S, Singh DV, Acharya N. Extracellular vesicles: An emerging platform in gram-positive bacteria. MICROBIAL CELL (GRAZ, AUSTRIA) 2020; 7:312-322. [PMID: 33335921 PMCID: PMC7713254 DOI: 10.15698/mic2020.12.737] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/07/2020] [Accepted: 09/23/2020] [Indexed: 12/11/2022]
Abstract
Extracellular vesicles (EV), also known as membrane vesicles, are produced as an end product of secretion by both pathogenic and non-pathogenic bacteria. Several reports suggest that archaea, gram-negative bacteria, and eukaryotic cells secrete membrane vesicles as a means for cell-free intercellular communication. EVs influence intercellular communication by transferring a myriad of biomolecules including genetic information. Also, EVs have been implicated in many phenomena such as stress response, intercellular competition, lateral gene transfer, and pathogenicity. However, the cellular process of secreting EVs in gram-positive bacteria is less studied. A notion with the thick cell-walled microbes such as gram-positive bacteria is that the EV release is impossible among them. The role of gram-positive EVs in health and diseases is being studied gradually. Being nano-sized, the EVs from gram-positive bacteria carry a diversity of cargo compounds that have a role in bacterial competition, survival, invasion, host immune evasion, and infection. In this review, we summarise the current understanding of the EVs produced by gram-positive bacteria. Also, we discuss the functional aspects of these components while comparing them with gram-negative bacteria.
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Affiliation(s)
- Swagata Bose
- Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar-751023, India
| | - Shifu Aggarwal
- Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar-751023, India
| | - Durg Vijai Singh
- Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar-751023, India
- Department of Biotechnology, School of Earth, Biological and Environmental Sciences, Central University of South Bihar, Gaya-824236, India
| | - Narottam Acharya
- Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar-751023, India
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31
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Berry SB, Haack AJ, Theberge AB, Brighenti S, Svensson M. Host and Pathogen Communication in the Respiratory Tract: Mechanisms and Models of a Complex Signaling Microenvironment. Front Med (Lausanne) 2020; 7:537. [PMID: 33015094 PMCID: PMC7511576 DOI: 10.3389/fmed.2020.00537] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 07/29/2020] [Indexed: 01/15/2023] Open
Abstract
Chronic lung diseases are a leading cause of morbidity and mortality across the globe, encompassing a diverse range of conditions from infections with pathogenic microorganisms to underlying genetic disorders. The respiratory tract represents an active interface with the external environment having the primary immune function of resisting pathogen intrusion and maintaining homeostasis in response to the myriad of stimuli encountered within its microenvironment. To perform these vital functions and prevent lung disorders, a chemical and biological cross-talk occurs in the complex milieu of the lung that mediates and regulates the numerous cellular processes contributing to lung health. In this review, we will focus on the role of cross-talk in chronic lung infections, and discuss how different cell types and signaling pathways contribute to the chronicity of infection(s) and prevent effective immune clearance of pathogens. In the lung microenvironment, pathogens have developed the capacity to evade mucosal immunity using different mechanisms or virulence factors, leading to colonization and infection of the host; such mechanisms include the release of soluble and volatile factors, as well as contact dependent (juxtracrine) interactions. We explore the diverse modes of communication between the host and pathogen in the lung tissue milieu in the context of chronic lung infections. Lastly, we review current methods and approaches used to model and study these host-pathogen interactions in vitro, and the role of these technological platforms in advancing our knowledge about chronic lung diseases.
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Affiliation(s)
- Samuel B. Berry
- Department of Medicine, Center for Infectious Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
- Department of Chemistry, University of Washington, Seattle, WA, United States
| | - Amanda J. Haack
- Department of Chemistry, University of Washington, Seattle, WA, United States
| | | | - Susanna Brighenti
- Department of Medicine, Center for Infectious Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Mattias Svensson
- Department of Medicine, Center for Infectious Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
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32
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Espinosa-Cueto P, Magallanes-Puebla A, Mancilla R. Phosphate starvation enhances phagocytosis of Mycobacterium bovis/BCG by macrophages. BMC Immunol 2020; 21:34. [PMID: 32517651 PMCID: PMC7282091 DOI: 10.1186/s12865-020-00364-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 06/04/2020] [Indexed: 01/07/2023] Open
Abstract
Background Tuberculosis is an important health problem worldwide. The only available vaccine is M. bovis/BCG, an attenuated mycobacterium that activates the innate and the acquired immune system after being phagocytosed by macrophages and dendritic cells. Vaccination fails to prevent adult pulmonary tuberculosis although it may have a protective effect in childhood infection. Understanding how BCG interacts with macrophages and other immunocompetent cells is crucial to develop new vaccines. Results In this study we showed that macrophages phagocytose M. bovis/BCG bacilli with higher efficiency when they are cultured without phosphate. We isolated mycobacterial membranes to search for mycobacterial molecules that could be involved in these processes; by immunoblot, it was found that the plasma membranes of phosphate-deprived bacilli express the adhesins PstS-1, LpqH, LprG, and the APA antigen. These proteins are not detected in membranes of bacilli grown with usual amounts of phosphate. Conclusions The interest of our observations is to show that under the metabolic stress implied in phosphate deprivation, mycobacteria respond upregulating adhesins that could improve their capacity to infect macrophages. These observations are relevant to understand how M. bovis/BCG induces protective immunity.
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Affiliation(s)
- Patricia Espinosa-Cueto
- Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Circuito Escolar S/N, Ciudad Universitaria, 04510, México City, Mexico
| | - Alejandro Magallanes-Puebla
- Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Circuito Escolar S/N, Ciudad Universitaria, 04510, México City, Mexico
| | - Raul Mancilla
- Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Circuito Escolar S/N, Ciudad Universitaria, 04510, México City, Mexico.
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Abstract
Mycobacterium tuberculosis remains the leading cause of death attributed to a single infectious organism. Bacillus Calmette-Guerin (BCG), the standard vaccine against M. tuberculosis, is thought to prevent only 5% of all vaccine-preventable deaths due to tuberculosis, thus an alternative vaccine is required. One of the principal barriers to vaccine development against M. tuberculosis is the complexity of the immune response to infection, with uncertainty as to what constitutes an immunological correlate of protection. In this paper, we seek to give an overview of the immunology of M. tuberculosis infection, and by doing so, investigate possible targets of vaccine development. This encompasses the innate, adaptive, mucosal and humoral immune systems. Though MVA85A did not improve protection compared with BCG alone in a large-scale clinical trial, the correlates of protection this has revealed, in addition to promising results from candidate such as VPM1002, M72/ASO1E and H56:IC31 point to a brighter future in the field of TB vaccine development.
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Affiliation(s)
- Benedict Brazier
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, OX3 7DQ UK
| | - Helen McShane
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, OX3 7DQ UK
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Structural basis and designing of peptide vaccine using PE-PGRS family protein of Mycobacterium ulcerans—An integrated vaccinomics approach. Mol Immunol 2020; 120:146-163. [DOI: 10.1016/j.molimm.2020.02.009] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Revised: 01/16/2020] [Accepted: 02/12/2020] [Indexed: 12/29/2022]
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Nfa34810 Facilitates Nocardia farcinica Invasion of Host Cells and Stimulates Tumor Necrosis Factor Alpha Secretion through Activation of the NF-κB and Mitogen-Activated Protein Kinase Pathways via Toll-Like Receptor 4. Infect Immun 2020; 88:IAI.00831-19. [PMID: 31964749 PMCID: PMC7093121 DOI: 10.1128/iai.00831-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 01/06/2020] [Indexed: 11/21/2022] Open
Abstract
The mechanism underlying the pathogenesis of Nocardia is not fully known. The Nfa34810 protein of Nocardia farcinica has been predicted to be a virulence factor. However, relatively little is known regarding the interaction of Nfa34810 with host cells, specifically invasion and innate immune activation. In this study, we aimed to determine the role of recombinant Nfa34810 during infection. We demonstrated that Nfa34810 is an immunodominant protein located in the cell wall. The mechanism underlying the pathogenesis of Nocardia is not fully known. The Nfa34810 protein of Nocardia farcinica has been predicted to be a virulence factor. However, relatively little is known regarding the interaction of Nfa34810 with host cells, specifically invasion and innate immune activation. In this study, we aimed to determine the role of recombinant Nfa34810 during infection. We demonstrated that Nfa34810 is an immunodominant protein located in the cell wall. Nfa34810 protein was able to facilitate the uptake and internalization of latex beads coated with Nfa34810 protein into HeLa cells. Furthermore, the deletion of the nfa34810 gene in N. farcinica attenuated the ability of the bacteria to infect both HeLa and A549 cells. Moreover, stimulation with Nfa34810 triggered macrophages to produce tumor necrosis factor alpha (TNF-α), and it also activated mitogen-activated protein kinase (MAPK) and nuclear factor κB (NF-κB) signaling pathways by inducing the phosphorylation of ERK1/2, p38, JNK, p65, and AKT in macrophages. Specific inhibitors of ERK1/2, JNK, and NF-κB significantly reduced the expression of TNF-α, which demonstrated that Nfa34810-mediated TNF-α production was dependent upon the activation of these kinases. We further found that neutralizing antibodies against Toll-like receptor 4 (TLR4) significantly inhibited TNF-α secretion. Taken together, our results indicated that Nfa34810 is a virulence factor of N. farcinica and plays an important role during infection. Nfa34810-induced production of TNF-α in macrophages also involves ERK, JNK, and NF-κB via the TLR4 pathway.
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Ji X, Zhang X, Sun L, Hou X, Song H, Han L, Xu S, Li H, Qiu X, Li M, Wang X, Zheng N, Li Z. The Heparin-Binding Hemagglutinin of Nocardia cyriacigeorgica GUH-2 Stimulates Inflammatory Cytokine Secretion Through Activation of Nuclear Factor κB and Mitogen-Activated Protein Kinase Pathways via TLR4. Front Cell Infect Microbiol 2020; 10:3. [PMID: 32117792 PMCID: PMC7031410 DOI: 10.3389/fcimb.2020.00003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 01/07/2020] [Indexed: 01/14/2023] Open
Abstract
Heparin-binding hemagglutinin (HBHA) from mycobacteria is involved in the dissemination of infection and the activation of the host immune response. However, the interaction of Nocardia cyriacigeorgica HBHA with the host cells remains unknown. In the present study, we describe N. cyriacigeorgica HBHA interactions with epithelial cells and organ colonization. We then investigate the mechanisms by which HBHA induces the production of inflammatory cytokines in macrophages. Immunofluorescent microscopy showed that HBHA adhered to A549 cells and HeLa cells and that the C-terminal fragment, which contains a Pro-Ala-Lys–rich domain, was responsible for adhesion. The deletion of the hbha gene in N. cyriacigeorgica mutant strains impaired adhesion to A549 cells and HeLa cells. In addition, the HBHA protein activated the mitogen-activated protein kinase (MAPK) and nuclear factor kappa B (NF-κB) signaling pathways and promoted the production of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-10 in macrophages. HBHA-mediated TNF-α production was dependent on the activation of the c-Jun N-terminal kinase (JNK) signal pathways, and the IL-6 and IL-10 production was dependent on the activation of extracellular regulated kinase (ERK) 1/2, MAPK p38 (p38), JNK, and nuclear NF-κB signaling pathways. Additionally, the HBHA-mediated activation of innate immunity was dependent on Toll-like receptor 4 (TLR4). Taken together, these results indicate that N. cyriacigeorgica HBHA not only adheres to epithelial cells and may be involved in organ colonization, but also plays a critical role in the modulation of innate immunity through the MAPK and NF-κB signaling pathways via TLR4.
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Affiliation(s)
- Xingzhao Ji
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Xiujuan Zhang
- Department of Endocrinology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Lina Sun
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Xuexin Hou
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Han Song
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.,School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, China
| | - Lichao Han
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.,Department of Medicine, Tibet University, Lhasa, China
| | - Shuai Xu
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Heqiao Li
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Xiaotong Qiu
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Minghui Li
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Xuebing Wang
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Ningwei Zheng
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.,School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, China
| | - Zhenjun Li
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
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37
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Revealing eukaryotic histone-modifying mechanisms through bacterial infection. Semin Immunopathol 2020; 42:201-213. [DOI: 10.1007/s00281-019-00778-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 12/27/2019] [Indexed: 12/12/2022]
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38
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Hu W, Yang S, Shimada Y, Münch M, Marín-Juez R, Meijer AH, Spaink HP. Infection and RNA-seq analysis of a zebrafish tlr2 mutant shows a broad function of this toll-like receptor in transcriptional and metabolic control and defense to Mycobacterium marinum infection. BMC Genomics 2019; 20:878. [PMID: 31747871 PMCID: PMC6869251 DOI: 10.1186/s12864-019-6265-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 11/05/2019] [Indexed: 02/07/2023] Open
Abstract
Background The function of Toll-like receptor 2 (TLR2) in host defense against pathogens, especially Mycobacterium tuberculosis (Mtb) is poorly understood. To investigate the role of TLR2 during mycobacterial infection, we analyzed the response of tlr2 zebrafish mutant larvae to infection with Mycobacterium marinum (Mm), a close relative to Mtb, as a model for tuberculosis. We measured infection phenotypes and transcriptome responses using RNA deep sequencing in mutant and control larvae. Results tlr2 mutant embryos at 2 dpf do not show differences in numbers of macrophages and neutrophils compared to control embryos. However, we found substantial changes in gene expression in these mutants, particularly in metabolic pathways, when compared with the heterozygote tlr2+/− control. At 4 days after Mm infection, the total bacterial burden and the presence of extracellular bacteria were higher in tlr2−/− larvae than in tlr2+/−, or tlr2+/+ larvae, whereas granuloma numbers were reduced, showing a function of Tlr2 in zebrafish host defense. RNAseq analysis of infected tlr2−/− versus tlr2+/− shows that the number of up-regulated and down-regulated genes in response to infection was greatly diminished in tlr2 mutants by at least 2 fold and 10 fold, respectively. Analysis of the transcriptome data and qPCR validation shows that Mm infection of tlr2 mutants leads to decreased mRNA levels of genes involved in inflammation and immune responses, including il1b, tnfb, cxcl11aa/ac, fosl1a, and cebpb. Furthermore, RNAseq analyses revealed that the expression of genes for Maf family transcription factors, vitamin D receptors, and Dicps proteins is altered in tlr2 mutants with or without infection. In addition, the data indicate a function of Tlr2 in the control of induction of cytokines and chemokines, such as the CXCR3-CXCL11 signaling axis. Conclusion The transcriptome and infection burden analyses show a function of Tlr2 as a protective factor against mycobacteria. Transcriptome analysis revealed tlr2-specific pathways involved in Mm infection, which are related to responses to Mtb infection in human macrophages. Considering its dominant function in control of transcriptional processes that govern defense responses and metabolism, the TLR2 protein can be expected to be also of importance for other infectious diseases and interactions with the microbiome.
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Affiliation(s)
- Wanbin Hu
- Institute of Biology, Leiden University, P.O. Box 9505, 2300 RA, Leiden, the Netherlands
| | - Shuxin Yang
- Institute of Biology, Leiden University, P.O. Box 9505, 2300 RA, Leiden, the Netherlands.,Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Yasuhito Shimada
- Institute of Biology, Leiden University, P.O. Box 9505, 2300 RA, Leiden, the Netherlands.,Department of Integrative Pharmacology, Mie University Graduate School of Medicine, Tsu, Japan
| | - Magnus Münch
- Mathematical Institute, Leiden University, Leiden, the Netherlands.,Department of Epidemiology & Biostatistics, Amsterdam Public Health Research Institute, Amsterdam University Medical Center, Amsterdam, the Netherlands
| | - Rubén Marín-Juez
- Institute of Biology, Leiden University, P.O. Box 9505, 2300 RA, Leiden, the Netherlands.,Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Ludwigstrasse 43, 61231, Bad Nauheim, Germany
| | - Annemarie H Meijer
- Institute of Biology, Leiden University, P.O. Box 9505, 2300 RA, Leiden, the Netherlands
| | - Herman P Spaink
- Institute of Biology, Leiden University, P.O. Box 9505, 2300 RA, Leiden, the Netherlands.
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Khan A, Bakhru P, Saikolappan S, Das K, Soudani E, Singh CR, Estrella JL, Zhang D, Pasare C, Ma Y, Sun J, Wang J, Hunter RL, Tony Eissa N, Dhandayuthapani S, Jagannath C. An autophagy-inducing and TLR-2 activating BCG vaccine induces a robust protection against tuberculosis in mice. NPJ Vaccines 2019; 4:34. [PMID: 31396406 PMCID: PMC6683161 DOI: 10.1038/s41541-019-0122-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 05/15/2019] [Indexed: 12/28/2022] Open
Abstract
Mycobacterium bovis BCG is widely used as a vaccine against tuberculosis due to M. tuberculosis (Mtb), which kills millions of people each year. BCG variably protects children, but not adults against tuberculosis. BCG evades phagosome maturation, autophagy, and reduces MHC-II expression of antigen-presenting cells (APCs) affecting T-cell activation. To bypass these defects, an autophagy-inducing, TLR-2 activating C5 peptide from Mtb-derived CFP-10 protein was overexpressed in BCG in combination with Ag85B. Recombinant BCG85C5 induced a robust MHC-II-dependent antigen presentation to CD4 T cells in vitro, and elicited stronger TH1 cytokines (IL-12, IL-1β, and TNFα) from APCs of C57Bl/6 mice increasing phosphorylation of p38MAPK and ERK. BCG85C5 also enhanced MHC-II surface expression of MΦs by inhibiting MARCH1 ubiquitin ligase that degrades MHC-II. BCG85C5 infected APCs from MyD88 or TLR-2 knockout mice showed decreased antigen presentation. Furthermore, BCG85C5 induced LC3-dependent autophagy in macrophages increasing antigen presentation. Consistent with in vitro effects, BCG85C5 markedly expanded both effector and central memory T cells in C57Bl/6 mice protecting them against both primary aerosol infection with Mtb and reinfection, but was less effective among TLR-2 knockout mice. Thus, BCG85C5 induces stronger and longer lasting immunity, and is better than BCG against tuberculosis of mice.
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Affiliation(s)
- Arshad Khan
- Department of Pathology and Laboratory Medicine, University of Texas Health Sciences Center, Houston, TX USA
| | - Pearl Bakhru
- Department of Pathology and Laboratory Medicine, University of Texas Health Sciences Center, Houston, TX USA
| | - Sankaralingam Saikolappan
- Molecular and Translational Medicine, Paul L. Foster School of Medicine Texas Tech University Health Sciences Center, El Paso, TX USA
| | - Kishore Das
- Molecular and Translational Medicine, Paul L. Foster School of Medicine Texas Tech University Health Sciences Center, El Paso, TX USA
| | - Emily Soudani
- Department of Pathology and Laboratory Medicine, University of Texas Health Sciences Center, Houston, TX USA
| | - Christopher R. Singh
- Department of Pathology and Laboratory Medicine, University of Texas Health Sciences Center, Houston, TX USA
| | - Jaymie L. Estrella
- Department of Pathology and Laboratory Medicine, University of Texas Health Sciences Center, Houston, TX USA
| | - Dekai Zhang
- Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, TX USA
| | - Chandrashekhar Pasare
- Division of Immunobiology, Center for Inflammation and Tolerance, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229 USA
| | - Yue Ma
- Department of Biological Sciences and Border Biomedical Research Center, University of Texas at El Paso, Houston, TX USA
| | - Jianjun Sun
- Department of Biological Sciences and Border Biomedical Research Center, University of Texas at El Paso, Houston, TX USA
| | - Jin Wang
- Methodist Hospital Research Institute, Houston, TX USA
| | - Robert L. Hunter
- Department of Pathology and Laboratory Medicine, University of Texas Health Sciences Center, Houston, TX USA
| | | | - Subramanian Dhandayuthapani
- Molecular and Translational Medicine, Paul L. Foster School of Medicine Texas Tech University Health Sciences Center, El Paso, TX USA
| | - Chinnaswamy Jagannath
- Department of Pathology and Laboratory Medicine, University of Texas Health Sciences Center, Houston, TX USA
- Methodist Hospital Research Institute, Houston, TX USA
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40
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Gao X, Wu C, He W, Wang X, Li Y, Wang Y, Jia Y, Yuan R, Li H, Zhang B. DosR antigen Rv1737c induces activation of macrophages dependent on the TLR2 pathway. Cell Immunol 2019; 344:103947. [PMID: 31326120 DOI: 10.1016/j.cellimm.2019.103947] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Revised: 06/13/2019] [Accepted: 06/27/2019] [Indexed: 01/22/2023]
Abstract
Latent Mycobacterium tuberculosis (Mtb) infection (LTBI) is the main clinical manifestation after Mtb exposure. During the latent phase, Mtb retards the attempts of eradication by the host immune system. The dormancy survival regulator (DosR) is held as essential for Mtb persistence. Rv1737c is predominantly expressed by the Mtb in latent infection. However, the role of Rv1737c in the immune evasion is still largely unknown. In this study, we have characterized the Rv1737c functions in the recruitment and activation of macrophages, which play a cardinal role in the innate and adaptive immunity. For the first time, we have revealed that Rv1737c induced the tolerogenic phenotype of macrophages by upregulating the expression of indoleamine 2,3-dioxygenase 1 (IDO1). Rv1737c-activated macrophages upregulated interleukin (IL)-4, IL-10, and Foxp3 T cells proliferation in vitro. Furthermore, the interaction of Rv1737c with macrophages was found to depend on the Toll-like receptor 2 (TLR2) pathway. It augmented nuclear factor κB (NF-κB) phosphorylation and co-stimulatory molecule expression. Thus, this study provides a crucial insight into a strategy adopted by Mtb to survive in the host by inducing tolerogenic macrophage expansion.
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Affiliation(s)
- Xiaoling Gao
- The Institute of Clinical Research and Translational Medicine, Gansu Provincial Hospital, Lanzhou, China.
| | - Cong Wu
- School of Public Health, Lanzhou University, Lanzhou, China
| | - Wenhua He
- School of Public Health, Lanzhou University, Lanzhou, China
| | - Xiaoxia Wang
- School of Public Health, Lanzhou University, Lanzhou, China
| | - Yonghong Li
- The Institute of Clinical Research and Translational Medicine, Gansu Provincial Hospital, Lanzhou, China
| | - Yongxiang Wang
- School of Public Health, Lanzhou University, Lanzhou, China
| | - Yanjuan Jia
- The Institute of Clinical Research and Translational Medicine, Gansu Provincial Hospital, Lanzhou, China
| | - Rui Yuan
- School of Public Health, Lanzhou University, Lanzhou, China
| | - Haojie Li
- School of Public Health, Lanzhou University, Lanzhou, China
| | - Benzhong Zhang
- School of Public Health, Lanzhou University, Lanzhou, China.
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Kamran-Sarkandi M, Behrouzi A, Fateh A, Vaziri F, Mirsaeidi M, Siadat SD. Mycobacterium avium Complex Extracellular Vesicles Attenuate Inflammation via Inducing IL-10. INTERNATIONAL JOURNAL OF MOLECULAR AND CELLULAR MEDICINE 2019; 7:241-250. [PMID: 31516884 PMCID: PMC6709930 DOI: 10.22088/ijmcm.bums.7.4.241] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Accepted: 04/24/2018] [Indexed: 12/27/2022]
Abstract
Mycobacterium avium complex (MAC) is an ubiquitous acid-fast bacterium. MAC cell wall and membrane release extracellular vesicles (EVs) into different media. The immunogenic effects of EVs isolated from MAC remain unknown. The aim of this study was to determine the EVs effect on macrophage cytokine production. MAC EVs were extracted and purified using differential centrifuges also known as Claassen’s method, with some modifications. After protein analysis of EVs, and scanning electron microscopy (SEM), the EVs were injected into BALB/c mice for in vivo experiments. The concentration of interferon gamma (IFN-γ) and interleukin 10 (IL-10) in the spleen immune cell culture was measured by sandwich ELISA. We for the first time showed that MAC can naturally produce EVs. The extraction method was technically-feasible, efficient and affordable. The SEM analysis showed that EVs diameter was similar to other studies on mycobacteria, and EVs maintained their spatial characterization. The results of the cytokine assays indicated that EV-treated cells secreted IL-10 (P = 0.034) but not IFN-γ (P = 0.037). Our findings suggest that EVs of M. avium could have anti-inflammatory effects. They can be used as a suppressor or regulator of inflammation via IL-10. The replication of the anti-inflammatory response of MAC EVs in future studies may indicate a new therapeutic agent for inflammation.
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Affiliation(s)
| | - Ava Behrouzi
- Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran
| | - Aboulfazl Fateh
- Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran.,Microbiology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Farzam Vaziri
- Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran.,Microbiology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Mehdi Mirsaeidi
- Division of Pulmonary, Critical Care, Sleep and Allergy, Department of Medicine, University of Miami, Miller School of Medicine, Miami, USA
| | - Seyed Davar Siadat
- Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran.,Microbiology Research Center, Pasteur Institute of Iran, Tehran, Iran
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Jin C, Wu X, Dong C, Li F, Fan L, Xiong S, Dong Y. EspR promotes mycobacteria survival in macrophages by inhibiting MyD88 mediated inflammation and apoptosis. Tuberculosis (Edinb) 2019; 116:22-31. [PMID: 31153514 DOI: 10.1016/j.tube.2019.03.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 02/18/2019] [Accepted: 03/30/2019] [Indexed: 12/22/2022]
Abstract
Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis (Mtb), leading to about a million deaths each year. EspR is a DNA binding protein of Mtb which regulates expression of multiple genes and the activity of ESX-1 secretion system of the bacteria, with itself being secreted out as a substrate of ESX-1. We explored the function of secreted EspR in host cells by overexpressing the protein in murine macrophage cell line RAW264.7, infecting the cells with BCG which does not secrete EspR, and evaluating the antimicrobial responses of the cells. We found that EspR resulted in an increased intracellular bacteria load in macrophages. This is due to its inhibition on BCG induced expression of inflammatory cytokines and inducible nitric oxide synthase (iNOS), as well as host cell apoptosis. Mechanism study showed that EspR directly interacted with adaptor protein myeloid differentiation factor 88 (MyD88), suppressed MyD88 dependent Toll-like receptor (TLR) and IL-1R signal activation, thus reduced inflammatory responses and apoptosis in macrophages and promoted mycobacteria survival.
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Affiliation(s)
- Chunyan Jin
- Jiangsu Key Laboratory of Infection and Immunity, Institute of Biology and Medical Sciences, Soochow University, Postal address: 199 Renai Road, SIP, Suzhou, Jiangsu, China.
| | - Xiaoyu Wu
- Jiangsu Key Laboratory of Infection and Immunity, Institute of Biology and Medical Sciences, Soochow University, Postal address: 199 Renai Road, SIP, Suzhou, Jiangsu, China.
| | - Chunsheng Dong
- Jiangsu Key Laboratory of Infection and Immunity, Institute of Biology and Medical Sciences, Soochow University, Postal address: 199 Renai Road, SIP, Suzhou, Jiangsu, China.
| | - Fengge Li
- Jiangsu Key Laboratory of Infection and Immunity, Institute of Biology and Medical Sciences, Soochow University, Postal address: 199 Renai Road, SIP, Suzhou, Jiangsu, China.
| | - Lingbo Fan
- Jiangsu Key Laboratory of Infection and Immunity, Institute of Biology and Medical Sciences, Soochow University, Postal address: 199 Renai Road, SIP, Suzhou, Jiangsu, China.
| | - Sidong Xiong
- Jiangsu Key Laboratory of Infection and Immunity, Institute of Biology and Medical Sciences, Soochow University, Postal address: 199 Renai Road, SIP, Suzhou, Jiangsu, China.
| | - Yuanshu Dong
- Jiangsu Key Laboratory of Infection and Immunity, Institute of Biology and Medical Sciences, Soochow University, Postal address: 199 Renai Road, SIP, Suzhou, Jiangsu, China.
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Kwon KW, Choi HH, Han SJ, Kim JS, Kim WS, Kim H, Kim LH, Kang SM, Park J, Shin SJ. Vaccine efficacy of a Mycobacterium tuberculosis Beijing-specific proline-glutamic acid (PE) antigen against highly virulent outbreak isolates. FASEB J 2019; 33:6483-6496. [PMID: 30753099 DOI: 10.1096/fj.201802604r] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Bacillus Calmette-Guerin vaccine confers insufficient pulmonary protection against tuberculosis (TB), particularly the Mycobacterium tuberculosis (Mtb) Beijing strain infection. Identification of vaccine antigens (Ags) by considering Mtb genetic diversity is crucial for the development of improved TB vaccine. MTBK_20640, a new Beijing genotype-specific proline-glutamic acid-family Ag, was identified by comparative genomic analysis. Its immunologic features were characterized by evaluating interactions with dendritic cells (DCs), and immunogenicity and vaccine efficacy were determined against highly virulent Mtb Beijing outbreak Korean Beijing (K) strain and HN878 strain in murine infection model. MTBK_20640 induced DCs via TLR2 and downstream MAPK and NF-κB signaling pathways, effectively promoting naive CD4-positive (CD4+) T-cell proliferation and IFN-γ production. Different IFN-γ response was observed in mice infected with Mtb K or reference H37Rv strain. Significant induction of T helper type 1 cell-polarized Ag-specific multifunctional CD4+ T cells and a marked Ag-specific IgG2c response were observed in mice immunized with MTBK_20640/glucopyranosyl lipid adjuvant-stable emulsion. The immunization conferred long-term protection against 2 Mtb Beijing outbreak strains, as evidenced by a significant reduction in colony-forming units in the lung and spleen and reduced lung inflammation. MTBK_20640 vaccination conferred long-term protection against highly virulent Mtb Beijing strains. MTBK_20640 may be developed into a novel Ag component in multisubunit TB vaccines in the future.-Kwon, K. W., Choi, H.-H., Han, S. J., Kim, J.-S., Kim, W. S., Kim, H., Kim, L.-H., Kang, S. M., Park, J., Shin, S. J. Vaccine efficacy of a Mycobacterium tuberculosis Beijing-specific proline-glutamic acid (PE) antigen against highly virulent outbreak isolates.
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Affiliation(s)
- Kee Woong Kwon
- Department of Microbiology, Institute for Immunology and Immunological Disease, Brain Korea 21 Program for Leading Universities and Students (PLUS) Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
| | - Hong-Hee Choi
- Department of Microbiology, Institute for Immunology and Immunological Disease, Brain Korea 21 Program for Leading Universities and Students (PLUS) Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
| | - Seung Jung Han
- Department of Microbiology, Institute for Immunology and Immunological Disease, Brain Korea 21 Program for Leading Universities and Students (PLUS) Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
| | - Jong-Seok Kim
- Department of Microbiology, Institute for Immunology and Immunological Disease, Brain Korea 21 Program for Leading Universities and Students (PLUS) Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea.,Myunggok Medical Research Institute, College of Medicine, Konyang University, Daejeon, South Korea
| | - Woo Sik Kim
- Department of Microbiology, Institute for Immunology and Immunological Disease, Brain Korea 21 Program for Leading Universities and Students (PLUS) Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea.,Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup, South Korea
| | - Hongmin Kim
- Department of Microbiology, Institute for Immunology and Immunological Disease, Brain Korea 21 Program for Leading Universities and Students (PLUS) Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
| | - Lee-Han Kim
- Department of Microbiology, Institute for Immunology and Immunological Disease, Brain Korea 21 Program for Leading Universities and Students (PLUS) Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
| | - Soon Myung Kang
- Department of Microbiology, Institute for Immunology and Immunological Disease, Brain Korea 21 Program for Leading Universities and Students (PLUS) Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
| | - Jaehun Park
- Department of Microbiology, Institute for Immunology and Immunological Disease, Brain Korea 21 Program for Leading Universities and Students (PLUS) Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
| | - Sung Jae Shin
- Department of Microbiology, Institute for Immunology and Immunological Disease, Brain Korea 21 Program for Leading Universities and Students (PLUS) Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
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Chen Y, Xiao JN, Li Y, Xiao YJ, Xiong YQ, Liu Y, Wang SJ, Ji P, Zhao GP, Shen H, Lu SH, Fan XY, Wang Y. Mycobacterial Lipoprotein Z Triggers Efficient Innate and Adaptive Immunity for Protection Against Mycobacterium tuberculosis Infection. Front Immunol 2019; 9:3190. [PMID: 30700988 PMCID: PMC6343430 DOI: 10.3389/fimmu.2018.03190] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 12/31/2018] [Indexed: 12/28/2022] Open
Abstract
Mycobacterial lipoproteins are considered to be involved in both virulence and immunoregulatory processes during Mycobacterium tuberculosis (M.tb) infection. In our previous investigations on the immunoreactivity of more than 30 M.tb proteins in active TB patients, we identified mycobacterial lipoprotein Z (LppZ) as one of the most immune dominant antigens. How LppZ triggers immune responses is still unclear. In this study, we analyzed LppZ-mediated innate and adaptive immunity using a murine air pouch model and an M.tb infection model, respectively. We found that LppZ could not only recruit inflammatory cells but also induce the production of proinflammatory cytokines inside the pouches. LppZ could also induce strong Th1 responses following immunization and confer protection against challenge with M.tb virulent strain H37Rv at a similar level to BCG vaccination but with less pathological damage in the lungs. Furthermore, we revealed the presence of LppZ-specific functional CD4+ T cells in the lungs of the challenged mice that were capable of secreting double or triple cytokines, including IFN-γ, IL-2, and TNF-α. Our study thus demonstrates that LppZ is of strong immunogenicity during M.tb infection in both humans and mice and has the ability to trigger effective innate and cellular immunity. Considering the limitations of candidate antigens in the pipeline of TB vaccine development, LppZ-mediated immune protection against M.tb challenge in the mouse model implies its potential application in vaccine development.
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Affiliation(s)
- Yingying Chen
- Department of Microbiology and Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, China
| | - Jia-Ni Xiao
- Department of Microbiology and Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, China
| | - Yong Li
- Department of Microbiology and Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, China
| | - Yang-Jiong Xiao
- Department of Microbiology and Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, China
| | - Yan-Qing Xiong
- Key Laboratory of Medical Molecular Virology of MOE/MOH, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Ying Liu
- Department of Microbiology and Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, China
| | - Shu-Jun Wang
- Department of Microbiology and Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, China
| | - Ping Ji
- Department of Microbiology and Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, China
| | - Guo-Ping Zhao
- Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China
| | - Hao Shen
- Department of Microbiology and Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, China.,Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Shui-Hua Lu
- Key Laboratory of Medical Molecular Virology of MOE/MOH, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Xiao-Yong Fan
- Key Laboratory of Medical Molecular Virology of MOE/MOH, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China.,TB Center, Shanghai Emerging and Re-emerging Infectious Disease Institute, Fudan University, Shanghai, China
| | - Ying Wang
- Department of Microbiology and Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai Institute of Immunology, Shanghai, China.,Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China
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Mycobacteria and their sweet proteins: An overview of protein glycosylation and lipoglycosylation in M. tuberculosis. Tuberculosis (Edinb) 2019; 115:1-13. [PMID: 30948163 DOI: 10.1016/j.tube.2019.01.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 01/10/2019] [Accepted: 01/13/2019] [Indexed: 12/16/2022]
Abstract
Post-translational modifications represent a key aspect of enzyme and protein regulation and function. Post-translational modifications are involved in signaling and response to stress, adaptation to changing environments, regulation of toxic and damaged proteins, proteins localization and host-pathogen interactions. Glycosylation in Mycobacterium tuberculosis (Mtb), is a post-translational modification often found in conjunction with acylation in mycobacterial proteins. Since the discovery of glycosylated proteins in the early 1980's, important advances in our understanding of the mechanisms of protein glycosylation have been made. The number of known glycosylated substrates in Mtb has grown through the years, yet many questions remain. This review will explore the current knowledge on protein glycosylation in Mtb, causative agent of Tuberculosis and number one infectious killer in the world. The mechanism and significance of this post-translational modification, as well as maturation, export and acylation of glycosylated proteins will be reviewed. We expect to provide the reader with an overall view of protein glycosylation in Mtb, as well as the significance of this post-translational modification to the physiology and host-pathogen interactions of this important pathogen. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier PXD011081 and 10.6019/PXD011081.
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46
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Non-classical circulating monocytes in severe obesity and obesity with uncontrolled diabetes: A comparison with tuberculosis and healthy individuals. Tuberculosis (Edinb) 2019; 114:30-41. [DOI: 10.1016/j.tube.2018.11.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 11/01/2018] [Accepted: 11/02/2018] [Indexed: 12/30/2022]
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47
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Aguilar-López BA, Correa F, Moreno- Altamirano MMB, Espitia C, Hernández-Longoria R, Oliva-Ramírez J, Padierna-Olivos J, Sánchez-García FJ. LprG and PE_PGRS33 Mycobacterium tuberculosis
virulence factors induce differential mitochondrial dynamics in macrophages. Scand J Immunol 2018; 89:e12728. [DOI: 10.1111/sji.12728] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 10/05/2018] [Accepted: 10/21/2018] [Indexed: 12/15/2022]
Affiliation(s)
- Bruno A. Aguilar-López
- Laboratorio de Inmunorregulación; Departamento de Inmunología; Escuela Nacional de Ciencias Biológicas; Instituto Politécnico Nacional; Mexico City Mexico
| | - Francisco Correa
- Departamento de Biomedicina Cardiovascular; Instituto Nacional de Cardiología “Ignacio Chávez”; Mexico City Mexico
| | - María Maximina B. Moreno- Altamirano
- Laboratorio de Inmunorregulación; Departamento de Inmunología; Escuela Nacional de Ciencias Biológicas; Instituto Politécnico Nacional; Mexico City Mexico
| | - Clara Espitia
- Departamento de Inmunología; Instituto de Investigaciones Biomédicas; Universidad Nacional Autónoma de México; Mexico City Mexico
| | | | | | | | - Francisco J. Sánchez-García
- Laboratorio de Inmunorregulación; Departamento de Inmunología; Escuela Nacional de Ciencias Biológicas; Instituto Politécnico Nacional; Mexico City Mexico
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48
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Johndrow CT, Goldberg MF, Johnson AJ, Ng TW, Kunnath-Velayudhan S, Lauvau G, Kaplan DH, Gossel GH, Kadolsky UD, Yates AJ, Chan J, Jacobs WR, Porcelli SA. Suppression of Th1 Priming by TLR2 Agonists during Cutaneous Immunization Is Mediated by Recruited CCR2 + Monocytes. THE JOURNAL OF IMMUNOLOGY 2018; 201:3604-3616. [PMID: 30455402 DOI: 10.4049/jimmunol.1801185] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 10/19/2018] [Indexed: 12/24/2022]
Abstract
Effective subunit vaccines require the incorporation of adjuvants that stimulate cells of the innate immune system to generate protective adaptive immune responses. Pattern recognition receptor agonists are a growing class of potential adjuvants that can shape the character of the immune response to subunit vaccines by directing the polarization of CD4 T cell differentiation to various functional subsets. In the current study, we applied a high-throughput in vitro screen to assess murine CD4 T cell polarization by a panel of pattern recognition receptor agonists. This identified lipopeptides with TLR2 agonist activity as exceptional Th1-polarizing adjuvants. In vivo, we demonstrated that i.v. administration of TLR2 agonists with Ag in mice replicated the findings from in vitro screening by promoting strong Th1 polarization. In contrast, TLR2 agonists inhibited priming of Th1 responses when administered cutaneously in mice. This route-specific suppression was associated with infiltrating CCR2+ cells in the skin-draining lymph nodes and was not uniquely dependent on any of the well characterized subsets of dendritic cells known to reside in the skin. We further demonstrated that priming of CD4 T cells to generate Th1 effectors following immunization with the Mycobacterium bovis bacillus Calmette-Guérin (BCG) strain, a lipoprotein-rich bacterium recognized by TLR2, was dependent on the immunization route, with significantly greater Th1 responses with i.v. compared with intradermal administration of BCG. A more complete understanding of route-dependent TLR2 responses may be critical for informed design of novel subunit vaccines and for improvement of BCG and other vaccines based on live-attenuated organisms.
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Affiliation(s)
- Christopher T Johndrow
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Michael F Goldberg
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN 55455
| | - Alison J Johnson
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Tony W Ng
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461
| | | | - Gregoire Lauvau
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Daniel H Kaplan
- Department of Dermatology, University of Pittsburgh, Pittsburgh, PA 15261.,Department of Immunology, University of Pittsburgh, Pittsburgh, PA 15261
| | - Graeme H Gossel
- Department of Physics and Astronomy, Hunter College and the City University of New York, New York, NY 10065
| | - Ulrich D Kadolsky
- Biomedical Research Centre at Guy's and St. Thomas' National Health Service Foundation Trust and King's College London, London SE1 9RT, United Kingdom
| | - Andrew J Yates
- Department of Pathology and Cell Biology, Columbia University, New York, NY 10032
| | - John Chan
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461.,Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461; and
| | - William R Jacobs
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461.,Howard Hughes Medical Institute, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Steven A Porcelli
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461; .,Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461; and
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Mycobacterium tuberculosis Lipoprotein and Lipoglycan Binding to Toll-Like Receptor 2 Correlates with Agonist Activity and Functional Outcomes. Infect Immun 2018; 86:IAI.00450-18. [PMID: 30037791 DOI: 10.1128/iai.00450-18] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 07/14/2018] [Indexed: 11/20/2022] Open
Abstract
Mycobacterium tuberculosis causes persistent infection due to its ability to evade host immune responses. M. tuberculosis induces Toll-like receptor 2 (TLR2) signaling, which influences immune responses to M. tuberculosis TLR2 agonists expressed by M. tuberculosis include lipoproteins (e.g., LprG), the glycolipid phosphatidylinositol mannoside 6 (PIM6), and the lipoglycan lipomannan (LM). Another M. tuberculosis lipoglycan, mannose-capped lipoarabinomannan (ManLAM), lacks TLR2 agonist activity. In contrast, PILAM, from Mycobacterum smegmatis, does have TLR2 agonist activity. Our understanding of how M. tuberculosis lipoproteins and lipoglycans interact with TLR2 is limited, and binding of these molecules to TLR2 has not been measured directly. Here, we directly measured M. tuberculosis lipoprotein and lipoglycan binding to TLR2 and its partner receptor, TLR1. LprG, LAM, and LM were all found to bind to TLR2 in the absence of TLR1, but not to TLR1 in the absence of TLR2. Trimolecular interactions were revealed by binding of TLR2-LprG or TLR2-PIM6 complexes to TLR1, whereas binding of TLR2 to TLR1 was not detected in the absence of the lipoprotein or glycolipid. ManLAM exhibited low affinity for TLR2 in comparison to PILAM, LM, and LprG, which correlated with reduced ability of ManLAM to induce TLR2-mediated extracellular-signal-regulated kinase (ERK) activation and tumor necrosis factor alpha (TNF-α) secretion in macrophages. We provide the first direct affinity measurement and kinetic analysis of M. tuberculosis lipoprotein and lipoglycan binding to TLR2. Our results demonstrate that binding affinity correlates with the functional ability of agonists to induce TLR2 signaling.
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50
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Houston S, Lithgow KV, Osbak KK, Kenyon CR, Cameron CE. Functional insights from proteome-wide structural modeling of Treponema pallidum subspecies pallidum, the causative agent of syphilis. BMC STRUCTURAL BIOLOGY 2018; 18:7. [PMID: 29769048 PMCID: PMC5956850 DOI: 10.1186/s12900-018-0086-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 04/27/2018] [Indexed: 12/21/2022]
Abstract
Background Syphilis continues to be a major global health threat with 11 million new infections each year, and a global burden of 36 million cases. The causative agent of syphilis, Treponema pallidum subspecies pallidum, is a highly virulent bacterium, however the molecular mechanisms underlying T. pallidum pathogenesis remain to be definitively identified. This is due to the fact that T. pallidum is currently uncultivatable, inherently fragile and thus difficult to work with, and phylogenetically distinct with no conventional virulence factor homologs found in other pathogens. In fact, approximately 30% of its predicted protein-coding genes have no known orthologs or assigned functions. Here we employed a structural bioinformatics approach using Phyre2-based tertiary structure modeling to improve our understanding of T. pallidum protein function on a proteome-wide scale. Results Phyre2-based tertiary structure modeling generated high-confidence predictions for 80% of the T. pallidum proteome (780/978 predicted proteins). Tertiary structure modeling also inferred the same function as primary structure-based annotations from genome sequencing pipelines for 525/605 proteins (87%), which represents 54% (525/978) of all T. pallidum proteins. Of the 175 T. pallidum proteins modeled with high confidence that were not assigned functions in the previously annotated published proteome, 167 (95%) were able to be assigned predicted functions. Twenty-one of the 175 hypothetical proteins modeled with high confidence were also predicted to exhibit significant structural similarity with proteins experimentally confirmed to be required for virulence in other pathogens. Conclusions Phyre2-based structural modeling is a powerful bioinformatics tool that has provided insight into the potential structure and function of the majority of T. pallidum proteins and helped validate the primary structure-based annotation of more than 50% of all T. pallidum proteins with high confidence. This work represents the first T. pallidum proteome-wide structural modeling study and is one of few studies to apply this approach for the functional annotation of a whole proteome. Electronic supplementary material The online version of this article (10.1186/s12900-018-0086-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Simon Houston
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada
| | - Karen Vivien Lithgow
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada
| | | | - Chris Richard Kenyon
- HIV/STI Unit, Institute of Tropical Medicine, Antwerp, Belgium.,Division of Infectious Diseases and HIV Medicine, University of Cape Town, Cape Town, South Africa
| | - Caroline E Cameron
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada.
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