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Thymic Extracellular Matrix in the Thymopoiesis: Just a Supporting? BIOTECH 2022; 11:biotech11030027. [PMID: 35892932 PMCID: PMC9326736 DOI: 10.3390/biotech11030027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 07/09/2022] [Accepted: 07/13/2022] [Indexed: 11/25/2022] Open
Abstract
The generation of T lymphocytes (thymopoiesis) is one of the major functions of the thymus that occurs throughout life. Thymic epithelial cells actively participate in this process. However, less attention has been paid to extracellular matrix (ECM) elements of thymus and their role in thymocyte differentiation. To clarify this topic, we selected some studies that deal with thymic ECM, its modulation, and its effects on thymopoiesis in different models. We emphasize that further studies are needed in order to deepen this knowledge and to propose new alternatives for thymic ECM functions during thymopoiesis.
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Duarte MJ, Mascarenhas RS, Assis AF, Tanaka PP, Speck-Hernandez CA, Passos GA. Autoimmune regulator act in synergism with thymocyte adhesion in the control of lncRNAs in medullary thymic epithelial cells. Mol Immunol 2021; 140:127-135. [PMID: 34700158 DOI: 10.1016/j.molimm.2021.10.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 05/30/2021] [Accepted: 10/07/2021] [Indexed: 12/06/2022]
Abstract
The autoimmune regulator (Aire) gene in medullary thymic epithelial cells (mTECs) encodes the AIRE protein, which interacts with its partners within the nucleus. This "Aire complex" induces stalled RNA Pol II on chromatin to proceed with transcription elongation of a large set of messenger RNAs and microRNAs. Considering that RNA Pol II also transcribes long noncoding RNAs (lncRNAs), we hypothesized that Aire might be implicated in the upstream control of this RNA species. To test this, we employed a loss-of-function approach in which Aire knockout mTECs were compared to Aire wild-type mTECs for lncRNA transcriptional profiling both in vitro and in vivo model systems. RNA sequencing enables the differential expression profiling of lncRNAs when these cells adhere in vitro to thymocytes or do not adhere to them as a way to test the effect of cell adhesion. Sets of lncRNAs that are unique and that are shared in vitro and in vivo were identified. Among these, we found the Aire-dependent lncRNAs as for example, Platr28, Ifi30, Morrbid, Malat1, and Xist. This finding represents the first evidence that Aire mediates the transcription of lncRNAs in mTECs. Microarray hybridizations enabled us to observe that temporal thymocyte adhesion modulates the expression levels of such lncRNAs as Morrbid, Xist, and Fbxl12o after 36 h of adhesion. This finding shows the existence of a synergistic mechanism involving a link between thymocyte adhesion, Aire, and lncRNAs in mTECs that might be important for immune self-representation.
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Affiliation(s)
- Max Jordan Duarte
- Molecular Immunogenetics Group, Department of Genetics, Ribeirão Preto Medical School, University of São Paulo (USP), Ribeirão Preto, SP, Brazil
| | - Romário S Mascarenhas
- Molecular Immunogenetics Group, Department of Genetics, Ribeirão Preto Medical School, University of São Paulo (USP), Ribeirão Preto, SP, Brazil
| | - Amanda Freire Assis
- Molecular Immunogenetics Group, Department of Genetics, Ribeirão Preto Medical School, University of São Paulo (USP), Ribeirão Preto, SP, Brazil
| | - Pedro Paranhos Tanaka
- Molecular Immunogenetics Group, Department of Genetics, Ribeirão Preto Medical School, University of São Paulo (USP), Ribeirão Preto, SP, Brazil
| | - Cesar A Speck-Hernandez
- Program in Basic and Applied Immunology, Ribeirão Preto Medical School, University of São Paulo (USP), Ribeirão Preto, SP, Brazil
| | - Geraldo Aleixo Passos
- Molecular Immunogenetics Group, Department of Genetics, Ribeirão Preto Medical School, University of São Paulo (USP), Ribeirão Preto, SP, Brazil; Program in Basic and Applied Immunology, Ribeirão Preto Medical School, University of São Paulo (USP), Ribeirão Preto, SP, Brazil; Laboratory of Genetics and Molecular Biology, Department of Basic and Oral Biology, School of Dentistry of Ribeirão Preto, USP, Ribeirão Preto, SP, Brazil; Center for Cell-Based Therapy in Dentistry, USP, Ribeirão Preto, SP, Brazil.
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Linhares-Lacerda L, Palu CC, Ribeiro-Alves M, Paredes BD, Morrot A, Garcia-Silva MR, Cayota A, Savino W. Differential Expression of microRNAs in Thymic Epithelial Cells from Trypanosoma cruzi Acutely Infected Mice: Putative Role in Thymic Atrophy. Front Immunol 2015; 6:428. [PMID: 26347748 PMCID: PMC4543887 DOI: 10.3389/fimmu.2015.00428] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 08/06/2015] [Indexed: 12/21/2022] Open
Abstract
A common feature seen in acute infections is a severe atrophy of the thymus. This occurs in the murine model of acute Chagas disease. Moreover, in thymuses from Trypanosoma cruzi acutely infected mice, thymocytes exhibit an increase in the density of fibronectin and laminin integrin-type receptors, with an increase in migratory response ex vivo. Thymic epithelial cells (TEC) play a major role in the intrathymic T cell differentiation. To date, the consequences of molecular changes promoted by parasite infection upon thymus have not been elucidated. Considering the importance of microRNA for gene expression regulation, 85 microRNAs (mRNAs) were analyzed in TEC from T. cruzi acutely infected mice. The infection significantly modulated 29 miRNAs and modulation of 9 was also dependent whether TEC sorted out from the thymus exhibited cortical or medullary phenotype. In silico analysis revealed that these miRNAs may control target mRNAs known to be responsible for chemotaxis, cell adhesion, and cell death. Considering that we sorted TEC in the initial phase of thymocyte loss, it is conceivable that changes in TEC miRNA expression profile are functionally related to thymic atrophy, providing new clues to better understanding the mechanisms of the thymic involution seen in experimental Chagas disease.
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Affiliation(s)
- Leandra Linhares-Lacerda
- Laboratory on Thymus Research, Institute Oswaldo Cruz, Oswaldo Cruz Foundation , Rio de Janeiro , Brazil
| | - Cintia Cristina Palu
- Laboratory on Thymus Research, Institute Oswaldo Cruz, Oswaldo Cruz Foundation , Rio de Janeiro , Brazil
| | - Marcelo Ribeiro-Alves
- HIV/AIDS Clinical Research Center, National Institute of Infectious Diseases, Oswaldo Cruz Foundation , Rio de Janeiro , Brazil
| | - Bruno Diaz Paredes
- The National Institute of Science and Technology for Structural Biology and Bioimaging, Federal University of Rio de Janeiro , Rio de Janeiro , Brazil
| | - Alexandre Morrot
- Department of Immunology, Microbiology Institute, Federal University of Rio de Janeiro , Rio de Janeiro , Brazil
| | | | - Alfonso Cayota
- Functional Genomics Unit, Institut Pasteur de Montevideo , Montevideo , Uruguay
| | - Wilson Savino
- Laboratory on Thymus Research, Institute Oswaldo Cruz, Oswaldo Cruz Foundation , Rio de Janeiro , Brazil
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The expression of netrin-1 in the thymus and its effects on thymocyte adhesion and migration. Clin Dev Immunol 2013; 2013:462152. [PMID: 24369474 PMCID: PMC3863506 DOI: 10.1155/2013/462152] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 11/13/2013] [Indexed: 01/26/2023]
Abstract
Netrin-1, a known axon guidance molecule, being a secreted laminin-related molecule, has been suggested to be involved in multiple physiological and pathological conditions, such as organogenesis, angiogenesis, tumorigenesis, and inflammation-mediated tissue injury. However, its function in thymocyte development is still unknown. Here, we demonstrate that Netrin-1 is expressed in mouse thymus tissue and is primarily expressed in thymic stromal cells, and the expression of Netrin-1 in thymocytes can be induced by anti-CD3 antibody or IL-7 treatment. Importantly, Netrin-1 mediates the adhesion of thymocytes, and this effect is comparable to or greater than that of fibronectin. Furthermore, Netrin-1 specifically promotes the chemotaxis of CXCL12. These suggest that Netrin-1 may play an important role in thymocyte development.
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Thymic alterations induced by Plasmodium berghei: expression of matrix metalloproteinases and their tissue inhibitors. Cell Immunol 2012; 279:53-9. [PMID: 23089194 DOI: 10.1016/j.cellimm.2012.09.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 08/28/2012] [Accepted: 09/12/2012] [Indexed: 01/02/2023]
Abstract
The thymus plays a crucial role in the generation of T-cells, and so our laboratory has been interested in the study of the intrathymic events that occur during infection diseases and may cause disruption in its functions. Previously, we showed that thymus from experimentally Plasmodium berghei-infected mice present histological alterations with high levels of apoptosis, changes in cell migration-related molecules, and premature egress of immature thymocytes to periphery. In addition, parasites were found inside the thymus. In this work we investigated alterations in the expression pattern and activity of matrix metalloproteinases MMP-2 and -9, and their tissue inhibitors, TIMP-1 and TIMP-2. Our results show enhanced expression and widespread distribution of these molecules in thymus from infected animals. Also, the presence of active MMP-2 was detected. These data are suggestive of MMPs and TIMPs importance in the earlier observed changes in the extracellular matrix during thymic alterations after plasmodium infection.
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Ribeiro-Carvalho MM, Smaniotto S, Neves-Dos-Santos S, Mouço T, Savino W, Mello-Coelho V. Triiodothyronine modulates differential homing of recent thymic emigrants to peripheral lymphoid organs. Scand J Immunol 2007; 66:8-16. [PMID: 17587341 DOI: 10.1111/j.1365-3083.2007.01910.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The functioning of the immune system partially relies on T-cell exportation from the thymus, the major site of T-cell differentiation. Although the molecular mechanisms governing this process begin to be elucidated, it is not clear if thyroid hormones can alter the homing of recent thymic emigrants (RTE) to peripheral lymphoid organs. Herein, we investigated whether triiodothyronine (T(3)) could influence the homing of thymus-derived T cells. For that we used intrathymic injection of T(3) in combination with fluorescein isothiocyanate (FITC) to trace, 16 h later, FITC(+) cells, termed RTE, in peripheral lymphoid organs. We observed that T(3) stimulated thymocyte export, increasing the frequency of CD4(+) RTE and CD8(+) RTE in the subcutaneous and mesenteric lymph nodes. By contrast, the relative numbers of CD4(+) RTE in the spleen were decreased. T(3) also changed the differential distribution pattern of CD4(+) RTE, and to a lesser extent CD8(+) RTE in the peripheral lymphoid organs. Moreover, the expression of extracellular matrix (ECM) components, such as laminin and fibronectin, which are known to be involved in T-cell migration, increased in the lymph nodes but not in the spleen following intrathymic T(3) treatment. In conclusion, our data correspond to the first demonstration that in vivo treatment with thyroid hormone stimulates thymic T-cell homing and T-cell distribution in peripheral lymphoid organs.
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Affiliation(s)
- M M Ribeiro-Carvalho
- Laboratory on Thymus Research, Department of Immunology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, BrazilDepartment of Morphology, Center for Biological Sciences, Federal University of Alagoas, Maceió, BrazilDepartment of Clinical Analyses, Faculty of Pharmacy, Federal University of Juiz de Fora, Minas Gerais, BrazilMiguelote Viana Central Laboratory, SUS, Niterói, Rio de Janeiro, BrazilDepartment of Histology and Embriology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - S Smaniotto
- Laboratory on Thymus Research, Department of Immunology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, BrazilDepartment of Morphology, Center for Biological Sciences, Federal University of Alagoas, Maceió, BrazilDepartment of Clinical Analyses, Faculty of Pharmacy, Federal University of Juiz de Fora, Minas Gerais, BrazilMiguelote Viana Central Laboratory, SUS, Niterói, Rio de Janeiro, BrazilDepartment of Histology and Embriology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - S Neves-Dos-Santos
- Laboratory on Thymus Research, Department of Immunology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, BrazilDepartment of Morphology, Center for Biological Sciences, Federal University of Alagoas, Maceió, BrazilDepartment of Clinical Analyses, Faculty of Pharmacy, Federal University of Juiz de Fora, Minas Gerais, BrazilMiguelote Viana Central Laboratory, SUS, Niterói, Rio de Janeiro, BrazilDepartment of Histology and Embriology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - T Mouço
- Laboratory on Thymus Research, Department of Immunology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, BrazilDepartment of Morphology, Center for Biological Sciences, Federal University of Alagoas, Maceió, BrazilDepartment of Clinical Analyses, Faculty of Pharmacy, Federal University of Juiz de Fora, Minas Gerais, BrazilMiguelote Viana Central Laboratory, SUS, Niterói, Rio de Janeiro, BrazilDepartment of Histology and Embriology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - W Savino
- Laboratory on Thymus Research, Department of Immunology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, BrazilDepartment of Morphology, Center for Biological Sciences, Federal University of Alagoas, Maceió, BrazilDepartment of Clinical Analyses, Faculty of Pharmacy, Federal University of Juiz de Fora, Minas Gerais, BrazilMiguelote Viana Central Laboratory, SUS, Niterói, Rio de Janeiro, BrazilDepartment of Histology and Embriology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - V Mello-Coelho
- Laboratory on Thymus Research, Department of Immunology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, BrazilDepartment of Morphology, Center for Biological Sciences, Federal University of Alagoas, Maceió, BrazilDepartment of Clinical Analyses, Faculty of Pharmacy, Federal University of Juiz de Fora, Minas Gerais, BrazilMiguelote Viana Central Laboratory, SUS, Niterói, Rio de Janeiro, BrazilDepartment of Histology and Embriology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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Fridkis-Hareli M, Reinherz EL. New approaches to eliciting protective immunity through T cell repertoire manipulation: the concept of thymic vaccination. MEDICAL IMMUNOLOGY (LONDON, ENGLAND) 2004; 3:2. [PMID: 15588284 PMCID: PMC544398 DOI: 10.1186/1476-9433-3-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2004] [Accepted: 12/08/2004] [Indexed: 12/24/2022]
Abstract
Conventional vaccines afford protection against infectious diseases by expanding existing pathogen-specific peripheral lymphocytes, both CD8 cytotoxic effector (CTL) and CD4 helper T cells. The latter induce B cell maturation and antibody production. As a consequence, lymphocytes within the memory pool are poised to rapidly proliferate at the time of a subsequent infection. The "thymic vaccination" concept offers a novel way to alter the primary T cell repertoire through exposure of thymocytes to altered peptide ligands (APL) with reduced T cell receptor (TCR) affinity relative to cognate antigens recognized by those same TCRs. Thymocyte maturation (i.e. positive selection) is enhanced by low affinity interaction between a TCR and an MHC-bound peptide in the thymus and subsequent emigration of mature cells into the peripheral T lymphocyte pool follows. In principal, such variants of antigens derived from infectious agents could be utilized for peptide-driven maturation of thymocytes bearing pathogen-specific TCRs. To test this idea, APLs of gp33-41, a Db-restricted peptide derived from the lymphocytic choriomeningitis virus (LCMV) glycoprotein, and of VSV8, a Kb-restricted peptide from the vesicular stomatitis virus (VSV) nucleoprotein, have been designed and their influence on thymic maturation of specific TCR-bearing transgenic thymocytes examined in vivo using irradiation chimeras. Injection of APL resulted in positive selection of CD8 T cells expressing the relevant viral specificity and in the export of those virus-specific CTL to lymph nodes without inducing T cell proliferation. Thus, exogenous APL administration offers the potential of expanding repertoires in vivo in a manner useful to the organism. To efficiently peripheralize antigen-specific T cells, concomitant enhancement of mechanisms promoting thymocyte migration appears to be required. This commentary describes the rationale for thymic vaccination and addresses the potential prophylactic and therapeutic applications of this approach for treatment of infectious diseases and cancer. Thymic vaccination-induced peptide-specific T cells might generate effective immune protection against disease-causing agents, including those for which no effective natural protection exists.
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Affiliation(s)
- Masha Fridkis-Hareli
- Laboratory of Immunobiology, Department of Medical Oncology, Dana-Farber Cancer Institute, USA
- Department of Medicine, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Ellis L Reinherz
- Laboratory of Immunobiology, Department of Medical Oncology, Dana-Farber Cancer Institute, USA
- Department of Medicine, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
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Savino W, Mendes-Da-Cruz DA, Smaniotto S, Silva-Monteiro E, Villa-Verde DMS. Molecular mechanisms governing thymocyte migration: combined role of chemokines and extracellular matrix. J Leukoc Biol 2004; 75:951-61. [PMID: 15020651 DOI: 10.1189/jlb.1003455] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Cell migration is crucial for thymocyte differentiation, and the cellular interactions involved now begin to be unraveled, with chemokines, extracellular matrix (ECM) proteins, and their corresponding receptors being relevant in such oriented movement of thymocytes. This notion derives from in vitro, ex vivo, and in vivo experimental data, including those obtained in genetically engineered and spontaneous mutant mice. Thymic microenvironmental cells produce both groups of molecules, whereas developing thymocytes express chemokine and ECM receptors. It is important that although chemokines and ECM proteins can drive thymocyte migration per se, a combined role of these molecules likely concurs for the resulting migration patterns of thymocytes in their various differentiation stages. In this respect, among ECM moieties, there are proteins with opposing functions, such as laminin or fibronectin versus galectin-3, which promote, respectively, adhesion and de-adhesion of thymocytes to the thymic microenvironment. How chemokines and ECM are produced and degraded remains to be more clearly defined. Nevertheless, matrix metalloproteinases (MMPs) likely play a role in the intrathymic ECM breakdown. It is interesting that these molecules also degrade chemokines. Thus, the physiological migration of thymocytes should be conceived as a resulting vector of multiple, simultaneous, or sequential stimuli, involving chemokines, adhesive, and de-adhesive ECM proteins. Moreover, these interactions may be physiologically regulated in situ by matrix MMPs and are influenced by hormones. Accordingly, one can predict that pathological changes in any of these loops may result in abnormal thymocyte migration. This actually occurs in the murine infection by the protozoan Trypanosoma cruzi, the causative agent of Chagas disease. In this model, the abnormal release of immature thymocytes to peripheral lymphoid organs is correlated with the higher migratory response to ECM and chemokines. Lastly, the fine dissection of the mechanisms governing thymocyte migration will provide new clues for designing therapeutic strategies targeting developing T cells. The most important function of the thymus is to generate T lymphocytes, which once leaving the organ, are able to colonize specific regions of peripheral lymphoid organs, the T cell zones, where they can mount and regulate cell-mediated, immune responses. This intrathymic T cell differentiation is a complex sequence of biological events, comprising cell proliferation, differential membrane protein expression, gene rearrangements, massive programmed cell death, and cell migration. In this review, we will focus on the mechanisms involved in controlling the migration of thymocytes, from the entrance of cell precursors into the organ to the exit of mature T cells toward peripheral lymphoid organs. Nevertheless, to better comprehend this issue, it appeared worthwhile to briefly comment on some key aspects of thymocyte differentiation and the tissue context in which it takes place, the thymic microenvironment.
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Affiliation(s)
- Wilson Savino
- Department of Immunology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Ave. Brasil 4365, Manguinhos, 21045-900-Rio de Janeiro, RJ, Brazil.
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