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Heidari M, Pakdel A, Bakhtiarizadeh MR, Dehghanian F. Integrated Analysis of lncRNAs, mRNAs, and TFs to Identify Regulatory Networks Underlying MAP Infection in Cattle. Front Genet 2021; 12:668448. [PMID: 34290737 PMCID: PMC8287970 DOI: 10.3389/fgene.2021.668448] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 06/04/2021] [Indexed: 11/29/2022] Open
Abstract
Johne’s disease is a chronic infection of ruminants that burdens dairy herds with a significant economic loss. The pathogenesis of the disease has not been revealed clearly due to its complex nature. In order to achieve deeper biological insights into molecular mechanisms involved in MAP infection resulting in Johne’s disease, a system biology approach was used. As far as is known, this is the first study that considers lncRNAs, TFs, and mRNAs, simultaneously, to construct an integrated gene regulatory network involved in MAP infection. Weighted gene coexpression network analysis (WGCNA) and functional enrichment analysis were conducted to explore coexpression modules from which nonpreserved modules had altered connectivity patterns. After identification of hub and hub-hub genes as well as TFs and lncRNAs in the nonpreserved modules, integrated networks of lncRNA-mRNA-TF were constructed, and cis and trans targets of lncRNAs were identified. Both cis and trans targets of lncRNAs were found in eight nonpreserved modules. Twenty-one of 47 nonpreserved modules showed significant biological processes related to the immune system and MAP infection. Some of the MAP infection’s related pathways in the most important nonpreserved modules comprise “positive regulation of cytokine-mediated signaling pathway,” “negative regulation of leukocyte migration,” “T-cell differentiation,” “neutrophil activation,” and “defense response.” Furthermore, several genes were identified in these modules, including SLC11A1, MAPK8IP1, HMGCR, IFNGR1, CMPK2, CORO1A, IRF1, LDLR, BOLA-DMB, and BOLA-DMA, which are potentially associated with MAP pathogenesis. This study not only enhanced our knowledge of molecular mechanisms behind MAP infection but also highlighted several promising hub and hub-hub genes involved in macrophage-pathogen interaction.
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Affiliation(s)
- Maryam Heidari
- Department of Animal Sciences, College of Agriculture, Isfahan University of Technology, Isfahan, Iran
| | - Abbas Pakdel
- Department of Animal Sciences, College of Agriculture, Isfahan University of Technology, Isfahan, Iran
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Blanco Vázquez C, Alonso-Hearn M, Juste RA, Canive M, Iglesias T, Iglesias N, Amado J, Vicente F, Balseiro A, Casais R. Detection of latent forms of Mycobacterium avium subsp. paratuberculosis infection using host biomarker-based ELISAs greatly improves paratuberculosis diagnostic sensitivity. PLoS One 2020; 15:e0236336. [PMID: 32881863 PMCID: PMC7470414 DOI: 10.1371/journal.pone.0236336] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 07/02/2020] [Indexed: 12/22/2022] Open
Abstract
Bovine paratuberculosis (PTB) is a chronic granulomatous enteritis, caused by Mycobacterium avium subsp. paratuberculosis (MAP), responsible for important economic losses in the dairy industry. Current diagnostic methods have low sensitivities for detection of latent forms of MAP infection, defined by focal granulomatous lesions and scarce humoral response or MAP presence. In contrast, patent infections correspond to multifocal and diffuse types of enteritis where there is increased antibody production, and substantial mycobacterial load. Our previous RNA-Seq analysis allowed the selection of five candidate biomarkers overexpressed in peripheral blood of MAP infected Holstein cows with focal (ABCA13 and MMP8) and diffuse (FAM84A, SPARC and DES) lesions vs. control animals with no detectable PTB-associated lesions in intestine and regional lymph nodes. The aim of the current study was to assess the PTB diagnostic potential of commercial ELISAs designed for the specific detection of these biomarkers. The ability of these ELISAs to identify animals with latent and/or patent forms of MAP infection was investigated using serum from naturally infected cattle (n = 88) and non-infected control animals (n = 67). ROC analysis revealed that the ABCA13-based ELISA showed the highest diagnostic accuracy for the detection of infected animals with focal lesions (AUC 0.837, sensitivity 79.25% and specificity 88.06%) and with any type of histological lesion (AUC 0.793, sensitivity 69.41% and specificity 86.57%) improving on the diagnostic performance of the popular IDEXX ELISA and other conventional diagnostic methods. SPARC and MMP8 showed the highest diagnostic accuracy for the detection of animals with multifocal (AUC 0.852) and diffuse lesions (AUC 0.831), respectively. In conclusion, our results suggest that quantification of ABCA13, SPARC and MMP8 by ELISA has the potential for implementation as a diagnostic tool to reliably identify MAP infection, greatly improving early detection of MAP latent infections when antibody responses and fecal shedding are undetectable using conventional diagnostic methods.
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Affiliation(s)
- Cristina Blanco Vázquez
- Servicio Regional de Investigación y Desarrollo Agroalimentario (SERIDA), Deva Gijón, Asturias, Spain
| | - Marta Alonso-Hearn
- Animal Health Department, NEIKER-Instituto Vasco de Investigación y Desarrollo Agrario, Derio, Bizkaia, Spain
| | - Ramón A. Juste
- Animal Health Department, NEIKER-Instituto Vasco de Investigación y Desarrollo Agrario, Derio, Bizkaia, Spain
- Servicio Regional de Investigación y Desarrollo Agroalimentario (SERIDA), Villaviciosa, Asturias, Spain
| | - María Canive
- Animal Health Department, NEIKER-Instituto Vasco de Investigación y Desarrollo Agrario, Derio, Bizkaia, Spain
| | - Tania Iglesias
- Unidad de Consultoría Estadística, Servicios científico-técnicos, Universidad de Oviedo, Campus de Gijón, Asturias, Spain
| | - Natalia Iglesias
- Servicio Regional de Investigación y Desarrollo Agroalimentario (SERIDA), Deva Gijón, Asturias, Spain
| | - Javier Amado
- Departament of Microbiology and Parasitology, Laboratorio de Sanidad Animal del Principado de Asturias (LSAPA), Gijón, Asturias, Spain
| | - Fernando Vicente
- Servicio Regional de Investigación y Desarrollo Agroalimentario (SERIDA), Villaviciosa, Asturias, Spain
| | - Ana Balseiro
- Servicio Regional de Investigación y Desarrollo Agroalimentario (SERIDA), Deva Gijón, Asturias, Spain
- Department of Animal Health, Facultad de Veterinaria, Instituto Ganadería de Montaña (CSIC-ULE), University of León, León, Spain
| | - Rosa Casais
- Servicio Regional de Investigación y Desarrollo Agroalimentario (SERIDA), Deva Gijón, Asturias, Spain
- * E-mail:
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Chongwe G, Michelo C, Sinkala E, Kayamba V, Nzayisenga JB, Drobniewski F, Kelly P. Mycobacterium avium lysate induces matrix metalloproteinase-1 in intestinal tissue and peripheral blood: Observations from selected hospital based Zambian adults. Int J Infect Dis 2018; 71:73-81. [PMID: 29680481 PMCID: PMC5985370 DOI: 10.1016/j.ijid.2018.03.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 03/16/2018] [Accepted: 03/30/2018] [Indexed: 01/23/2023] Open
Abstract
OBJECTIVES Environmental enteropathy is prevalent in low-income countries, although its aetiology is unknown. We investigated if Mycobacterium avium antigens, which are commonly found in the environment, could contribute to its pathogenesis in a population known to have widespread environmental enteropathy. METHODS Routine endoscopy patients at the University Teaching Hospital, Lusaka whose endoscopy results were normal submitted duodenal biopsies and whole blood samples. Samples were stimulated with M. avium lysate over 24h while unstimulated samples served as negative controls. Matrix metalloproteinase (MMP) and cytokine response in supernatants were quantified using ELISA and cytometric bead array. RESULTS Samples from 48 patients (56% women) were analysed, with a median age of 35 years (IQR 27.5, 50.5). M. avium induced the secretion of a wide-range of Th1, Th2 and Th17 cytokines in blood but only IL-1β and IL-6 in duodenal tissue. However it differentially induced the secretion of MMP-1 in duodenal tissue compared to negative controls (p=0.004). A similar MMP-1 response but with lower concentrations was observed in blood. CONCLUSION The induction of MMP-1 and cytokines by M. avium in duodenal tissue suggests that environmental mycobacteria could contribute to the epithelial disruption seen in environmental enteropathy, and a need to further explore possible biomarkers that may predict this exposure in at-risk populations.
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Affiliation(s)
- Gershom Chongwe
- Department of Epidemiology & Biostatistics, University of Zambia School of Public Health, Lusaka, Zambia.
| | - Charles Michelo
- Department of Epidemiology & Biostatistics, University of Zambia School of Public Health, Lusaka, Zambia; University of Zambia, Strategic Centre for Health Systems Metrics & Evaluations (SCHEME), School of Public Health, Lusaka, Zambia.
| | - Edford Sinkala
- Department of Internal Medicine, University of Zambia School of Medicine, Lusaka, Zambia.
| | - Violet Kayamba
- Department of Internal Medicine, University of Zambia School of Medicine, Lusaka, Zambia.
| | | | - Francis Drobniewski
- Infectious Diseases and Immunity, Department of Medicine, Imperial College, London, UK.
| | - Paul Kelly
- Department of Internal Medicine, University of Zambia School of Medicine, Lusaka, Zambia; Blizard Institute, Barts & The London School of Medicine, Queen Mary University of London, London, UK.
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Hempel RJ, Bannantine JP, Stabel JR. Transcriptional Profiling of Ileocecal Valve of Holstein Dairy Cows Infected with Mycobacterium avium subsp. Paratuberculosis. PLoS One 2016; 11:e0153932. [PMID: 27093613 PMCID: PMC4836751 DOI: 10.1371/journal.pone.0153932] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 04/06/2016] [Indexed: 12/22/2022] Open
Abstract
Johne’s disease is a chronic infection of the small intestine caused by Mycobacterium avium subspecies paratuberculosis (MAP), an intracellular bacterium. The events of pathogen survival within the host cell(s), chronic inflammation and the progression from asymptomatic subclinical stage to an advanced clinical stage of infection, are poorly understood. This study examines gene expression in the ileocecal valve (ICV) of Holstein dairy cows at different stages of MAP infection. The ICV is known to be a primary site of MAP colonization and provides an ideal location to identify genes that are relevant to the progression of this disease. RNA was prepared from ICV tissues and RNA-Seq was used to compare gene transcription between clinical, subclinical, and uninfected control animals. Interpretation of the gene expression data was performed using pathway analysis and gene ontology categories containing multiple differentially expressed genes. Results demonstrated that many of the pathways that had strong differential gene expression between uninfected control and clinical cows were related to the immune system, such as the T- and B-cell receptor signaling, apoptosis, NOD-like receptor signaling, and leukocyte transendothelial migration pathways. In contrast, the comparison of gene transcription between control and subclinical cows identified pathways that were primarily involved in metabolism. The results from the comparison between clinical and subclinical animals indicate recruitment of neutrophils, up regulation of lysosomal peptidases, increase in immune cell transendothelial migration, and modifications of the extracelluar matrix. This study provides important insight into how cattle respond to a natural MAP infection at the gene transcription level within a key target tissue for infection.
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Affiliation(s)
- Randy J. Hempel
- USDA-Agricultural Research Service (ARS), National Animal Disease Center, Ames, Iowa, United States of America
| | - John P. Bannantine
- USDA-Agricultural Research Service (ARS), National Animal Disease Center, Ames, Iowa, United States of America
| | - Judith R. Stabel
- USDA-Agricultural Research Service (ARS), National Animal Disease Center, Ames, Iowa, United States of America
- * E-mail:
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Liu JP, Liu D, Gu JF, Zhu MM, Cui L. Shikonin inhibits the cell viability, adhesion, invasion and migration of the human gastric cancer cell line MGC-803 via the Toll-like receptor 2/nuclear factor-kappa B pathway. J Pharm Pharmacol 2015; 67:1143-55. [PMID: 25880237 DOI: 10.1111/jphp.12402] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 01/25/2015] [Indexed: 12/19/2022]
Abstract
OBJECTIVES Shikonin is an active naphthoquinone pigment isolated from the root of Lithospermum erythrorhizon. This study was designed to explore the inhibition of Shikonin on cell viability, adhesion, migration and invasion ability of gastric cancer (GC) and its possible mechanism. METHODS 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed for cell viability and adhesion ability of MGC-803 cells. Cell scratch repair experiments were conducted for the determination of migration ability while transwell assay for cell invasion ability. Western blot analysis and real-time polymerase chain reaction assay were used for the detection of protein and mRNA expressions. KEY FINDINGS Fifty per cent inhibitory concentration of Shikonin on MGC-803 cells was 1.854 μm. Shikonin (1 μm) inhibited significantly the adhesion, invasion and migratory ability of MGC-803 cells. Interestingly, Shikonin in the presence or absence of anti-Toll-like receptor 2 (TLR2) antibody (2 μg) and nuclear factor-kappa B (NF-κB) inhibitor MG-132 (10 μm) could decrease these ability of MGC-803 cells markedly, as well as the expression levels of matrix metalloproteinases (MMP)-2, MMP-7, TLR2 and p65 NF-κB. In addition, the co-incubation of Shikonin and anti-TLR2/MG-132 has a significant stronger activity than anti-TLR2 or MG-132 alone. CONCLUSIONS The results indicated that Shikonin could suppress the cell viability, adhesion, invasion and migratory ability of MGC-803 cells through TLR2- or NF-κB-mediated pathway. Our findings provide novel information for the treatment of Shikonin on GC.
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Affiliation(s)
- Ji Ping Liu
- Key Laboratory of New Drug Delivery Systems of Chinese Materia Medica, Jiangsu Provincial Academy of Chinese Medicine, Nanjing, China.,Department of Pharmacology, Shaanxi University of Chinese Medicine, Xianyang, China
| | - Dan Liu
- Key Laboratory of New Drug Delivery Systems of Chinese Materia Medica, Jiangsu Provincial Academy of Chinese Medicine, Nanjing, China
| | - Jun Fei Gu
- Key Laboratory of New Drug Delivery Systems of Chinese Materia Medica, Jiangsu Provincial Academy of Chinese Medicine, Nanjing, China
| | - Mao Mao Zhu
- Key Laboratory of New Drug Delivery Systems of Chinese Materia Medica, Jiangsu Provincial Academy of Chinese Medicine, Nanjing, China
| | - Li Cui
- Key Laboratory of New Drug Delivery Systems of Chinese Materia Medica, Jiangsu Provincial Academy of Chinese Medicine, Nanjing, China
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Matrix metalloproteinases in inflammatory bowel disease: an update. Mediators Inflamm 2015; 2015:964131. [PMID: 25948887 PMCID: PMC4408746 DOI: 10.1155/2015/964131] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 09/07/2014] [Indexed: 02/07/2023] Open
Abstract
Matrix metalloproteinases (MMPs) are known to be upregulated in inflammatory bowel disease (IBD) and other inflammatory conditions, but while their involvement is clear, their role in many settings has yet to be determined. Studies of the involvement of MMPs in IBD since 2006 have revealed an array of immune and stromal cells which release the proteases in response to inflammatory cytokines and growth factors. Through digestion of the extracellular matrix and cleavage of bioactive proteins, a huge diversity of roles have been revealed for the MMPs in IBD, where they have been shown to regulate epithelial barrier function, immune response, angiogenesis, fibrosis, and wound healing. For this reason, MMPs have been recognised as potential biomarkers for disease activity in IBD and inhibition remains a huge area of interest. This review describes new roles of MMPs in the pathophysiology of IBD and suggests future directions for the development of treatment strategies in this condition.
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Atreya R, Bülte M, Gerlach GF, Goethe R, Hornef MW, Köhler H, Meens J, Möbius P, Roeb E, Weiss S. Facts, myths and hypotheses on the zoonotic nature of Mycobacterium avium subspecies paratuberculosis. Int J Med Microbiol 2014; 304:858-67. [PMID: 25128370 DOI: 10.1016/j.ijmm.2014.07.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Mycobacterium avium subspecies paratuberculosis (MAP) is the causative agent of paratuberculosis (Johne's disease [JD]), a chronic granulomatous enteritis in ruminants. JD is one of the most widespread bacterial diseases of domestic animals with significant economic impact. The histopathological picture of JD resembles that of Crohn's disease (CD), a human chronic inflammatory bowel disease of still unresolved aetiology. An aetiological relevance of MAP for CD has been proposed. This and the ambiguity of other published epidemiological findings raise the question whether MAP represents a zoonotic agent. In this review, we will discuss evidence that MAP has zoonotic capacity.
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Affiliation(s)
- Raja Atreya
- Medical Clinic 1, University of Erlangen-Nuermberg, Ulmenweg 18, D-91054 Erlangen, Germany
| | - Michael Bülte
- Institute of Veterinary Food Science, Faculty of Veterinary Medicine, Justus Liebig University, Frankfurter Straße 92, 35392 Gießen, Germany
| | | | - Ralph Goethe
- Institute for Microbiology, Department of Infectious Diseases, University of Veterinary Medicine Hannover, Bischofsholer Damm 15, 30173 Hannover, Germany.
| | - Mathias W Hornef
- Department of Microbiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Heike Köhler
- Institute of Molecular Pathogenesis, Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Naumburger Str. 96a, 07743 Jena, Germany
| | - Jochen Meens
- Institute for Microbiology, Department of Infectious Diseases, University of Veterinary Medicine Hannover, Bischofsholer Damm 15, 30173 Hannover, Germany
| | - Petra Möbius
- Institute of Molecular Pathogenesis, Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Naumburger Str. 96a, 07743 Jena, Germany
| | - Elke Roeb
- Justus-Liebig-University Giessen, Department of Gastroenterology, Klinikstr.33, 35392 Giessen, Germany
| | - Siegfried Weiss
- Helmholtz Centre for Infection Research, Molecular Immunology, Inhoffenstraße 7, 38124 Braunschweig, Germany
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Koc A, Bargen I, Suwandi A, Roderfeld M, Tschuschner A, Rath T, Gerlach GF, Hornef M, Goethe R, Weiss S, Roeb E. Systemic and mucosal immune reactivity upon Mycobacterium avium ssp. paratuberculosis infection in mice. PLoS One 2014; 9:e94624. [PMID: 24728142 PMCID: PMC3984212 DOI: 10.1371/journal.pone.0094624] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 03/19/2014] [Indexed: 12/19/2022] Open
Abstract
Mycobacterium avium ssp. paratuberculosis (MAP) is the cause of Johne's disease, an inflammatory bowel disorder of ruminants. Due to the similar pathology, MAP was also suggested to cause Crohn's disease (CD). Despite of intensive research, this question is still not settled, possibly due to the lack of versatile mouse models. The aim of this study was to identify basic immunologic mechanisms in response to MAP infection. Immune compromised C57BL/6 Rag2-/- mice were infected with MAP intraperitoneally. Such chronically infected mice were then reconstituted with CD4+ and CD8+ T cells 28 days after infection. A systemic inflammatory response, detected as enlargement of the spleen and granuloma formation in the liver, was observed in mice infected and reconstituted with CD4+ T cells. Whereby inflammation in infected and CD4+CD45RB(hi) T cell reconstituted animals was always higher than in the other groups. Reconstitution of infected animals with CD8+ T cells did not result in any inflammatory signs. Interestingly, various markers of inflammation were strongly up-regulated in the colon of infected mice reconstituted with CD4+CD45RB(lo/int) T cells. We propose, the usual non-colitogenic CD4+CD45RB(lo/int) T cells were converted into inflammatory T cells by the interaction with MAP. However, the power of such cells might be not sufficient for a fully established inflammatory response in the colon. Nevertheless, our model system appears to mirror aspects of an inflammatory bowel disease (IBD) like CD and Johne's diseases. Thus, it will provide an experimental platform on which further knowledge on IBD and the involvement of MAP in the induction of CD could be acquired.
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Affiliation(s)
- Arzu Koc
- Justus-Liebig-University Giessen, Department of Gastroenterology, Giessen, Germany
| | - Imke Bargen
- Helmholtz Centre for Infection Research, Molecular Immunology, Braunschweig, Germany
| | - Abdulhadi Suwandi
- Helmholtz Centre for Infection Research, Molecular Immunology, Braunschweig, Germany
| | - Martin Roderfeld
- Justus-Liebig-University Giessen, Department of Gastroenterology, Giessen, Germany
| | - Annette Tschuschner
- Justus-Liebig-University Giessen, Department of Gastroenterology, Giessen, Germany
| | - Timo Rath
- Justus-Liebig-University Giessen, Department of Gastroenterology, Giessen, Germany
- Medical Clinic 1, Friedrich-Alexander University Erlangen-Nuernberg, Erlangen, Germany
| | | | - Mathias Hornef
- Department of Microbiology, Hannover Medical School, Hannover, Germany
| | - Ralph Goethe
- Institute for Microbiology, Department of Infectious Diseases, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Siegfried Weiss
- Helmholtz Centre for Infection Research, Molecular Immunology, Braunschweig, Germany
| | - Elke Roeb
- Justus-Liebig-University Giessen, Department of Gastroenterology, Giessen, Germany
- * E-mail:
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Marinho FAV, de Paula RR, Mendes AC, de Almeida LA, Gomes MTR, Carvalho NB, Oliveira FS, Caliari MV, Oliveira SC. Toll-like receptor 6 senses Mycobacterium avium and is required for efficient control of mycobacterial infection. Eur J Immunol 2013; 43:2373-85. [PMID: 23716075 DOI: 10.1002/eji.201243208] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Revised: 04/30/2013] [Accepted: 05/23/2013] [Indexed: 01/08/2023]
Abstract
Mycobacterium avium has been reported to signal through both Toll-like receptor (TLR2) and TLR9. To investigate the role of TLR6 in innate immune responses to M. avium, TLR6, MyD88, TLR2, and TLR2/6 KO mice were infected with this pathogen. Bacterial burdens were higher in the lungs and livers of infected TLR6, TLR2, TLR2/6, and MyD88 KO mice compared with those in C57BL/6 mice, which indicates that TLR6 is required for the efficient control of M. avium infection. However, TLR6 KO spleen cells presented with normal M. avium induced IFN-γ responses as measured by ELISA and flow cytometry. In contrast, the production of IFN-γ in lung tissue was diminished in all studied KO mice. Furthermore, only MyD88 deficiency reduced granuloma areas in mouse livers. Moreover, we determined that TLR6 plays an important role in controlling bacterial growth within macrophages and in the production of TNF-α, IL-12, and IL-6 by M. avium infected DCs. Finally, the lack of TLR6 reduced activation of MAPKs and NF-κB in DCs. In summary, TLR6 is required for full resistance to M. avium and for the activation of DCs to produce proinflammatory cytokines.
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Affiliation(s)
- Fábio A V Marinho
- Departamento de Bioquimica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
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