1
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Shichkin VP, Antica M. Key Factors for Thymic Function and Development. Front Immunol 2022; 13:926516. [PMID: 35844535 PMCID: PMC9280625 DOI: 10.3389/fimmu.2022.926516] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 05/31/2022] [Indexed: 11/17/2022] Open
Abstract
The thymus is the organ responsible for T cell development and the formation of the adaptive immunity function. Its multicellular environment consists mainly of the different stromal cells and maturing T lymphocytes. Thymus-specific progenitors of epithelial, mesenchymal, and lymphoid cells with stem cell properties represent only minor populations. The thymic stromal structure predominantly determines the function of the thymus. The stromal components, mostly epithelial and mesenchymal cells, form this specialized area. They support the consistent developmental program of functionally distinct conventional T cell subpopulations. These include the MHC restricted single positive CD4+ CD8- and CD4- CD8+ cells, regulatory T lymphocytes (Foxp3+), innate natural killer T cells (iNKT), and γδT cells. Several physiological causes comprising stress and aging and medical treatments such as thymectomy and chemo/radiotherapy can harm the thymus function. The present review summarizes our knowledge of the development and function of the thymus with a focus on thymic epithelial cells as well as other stromal components and the signaling and transcriptional pathways underlying the thymic cell interaction. These critical thymus components are significant for T cell differentiation and restoring the thymic function after damage to reach the therapeutic benefits.
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2
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Rosichini M, Catanoso M, Screpanti I, Felli MP, Locatelli F, Velardi E. Signaling Crosstalks Drive Generation and Regeneration of the Thymus. Front Immunol 2022; 13:920306. [PMID: 35734178 PMCID: PMC9207182 DOI: 10.3389/fimmu.2022.920306] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 05/17/2022] [Indexed: 12/19/2022] Open
Abstract
Optimal recovery of immune competence after periods of hematopoietic insults or stress is crucial to re-establish patient response to vaccines, pathogens and tumor antigens. This is particularly relevant for patients receiving high doses of chemotherapy or radiotherapy, who experience prolonged periods of lymphopenia, which can be associated with an increased risk of infections, malignant relapse, and adverse clinical outcome. While the thymus represents the primary organ responsible for the generation of a diverse pool of T cells, its function is profoundly impaired by a range of acute insults (including those caused by cytoreductive chemo/radiation therapy, infections and graft-versus-host disease) and by the chronic physiological deterioration associated with aging. Impaired thymic function increases the risk of infections and tumor antigen escape due to a restriction in T-cell receptor diversity and suboptimal immune response. Therapeutic approaches that can promote the renewal of the thymus have the potential to restore immune competence in patients. Previous work has documented the importance of the crosstalk between thymocytes and thymic epithelial cells in establishing correct architecture and function of thymic epithelium. This crosstalk is relevant not only during thymus organogenesis, but also to promote the recovery of its function after injuries. In this review, we will analyze the signals involved in the crosstalk between TECs and hematopoietic cells. We will focus in particular on how signals from T-cells can regulate TEC function and discuss the relevance of these pathways in restoring thymic function and T-cell immunity in experimental models, as well as in the clinical setting.
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Affiliation(s)
- Marco Rosichini
- Department of Pediatric Hematology and Oncology, Cell and Gene Therapy, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy
- Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy
| | - Marialuigia Catanoso
- Department of Pediatric Hematology and Oncology, Cell and Gene Therapy, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy
| | - Isabella Screpanti
- Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy
| | - Maria Pia Felli
- Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy
| | - Franco Locatelli
- Department of Pediatric Hematology and Oncology, Cell and Gene Therapy, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy
- Department of Maternal and Child Health, Sapienza University of Rome, Rome, Italy
| | - Enrico Velardi
- Department of Pediatric Hematology and Oncology, Cell and Gene Therapy, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy
- *Correspondence: Enrico Velardi,
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3
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Martinez-Ruíz GU, Morales-Sánchez A, Bhandoola A. Transcriptional and epigenetic regulation in thymic epithelial cells. Immunol Rev 2022; 305:43-58. [PMID: 34750841 PMCID: PMC8766885 DOI: 10.1111/imr.13034] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/22/2021] [Accepted: 10/26/2021] [Indexed: 01/03/2023]
Abstract
The thymus is required for the development of both adaptive and innate-like T cell subsets. There is keen interest in manipulating thymic function for therapeutic purposes in circumstances of autoimmunity, immunodeficiency, and for purposes of immunotherapy. Within the thymus, thymic epithelial cells play essential roles in directing T cell development. Several transcription factors are known to be essential for thymic epithelial cell development and function, and a few transcription factors have been studied in considerable detail. However, the role of many other transcription factors is less well understood. Further, it is likely that roles exist for other transcription factors not yet known to be important in thymic epithelial cells. Recent progress in understanding of thymic epithelial cell heterogeneity has provided some new insight into transcriptional requirements in subtypes of thymic epithelial cells. However, it is unknown whether progenitors of thymic epithelial cells exist in the adult thymus, and consequently, developmental relationships linking putative precursors with differentiated cell types are poorly understood. While we do not presently possess a clear understanding of stage-specific requirements for transcription factors in thymic epithelial cells, new single-cell transcriptomic and epigenomic technologies should enable rapid progress in this field. Here, we review our current knowledge of transcription factors involved in the development, maintenance, and function of thymic epithelial cells, and the mechanisms by which they act.
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Affiliation(s)
- Gustavo Ulises Martinez-Ruíz
- T Cell Biology and Development Unit, Laboratory of Genome Integrity, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
- Research Division, Faculty of Medicine, National Autonomous University of Mexico, Mexico City, Mexico
- Children’s Hospital of Mexico Federico Gomez, Mexico City, Mexico
| | - Abigail Morales-Sánchez
- T Cell Biology and Development Unit, Laboratory of Genome Integrity, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
- Children’s Hospital of Mexico Federico Gomez, Mexico City, Mexico
| | - Avinash Bhandoola
- T Cell Biology and Development Unit, Laboratory of Genome Integrity, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
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4
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Borelli A, Irla M. Lymphotoxin: from the physiology to the regeneration of the thymic function. Cell Death Differ 2021; 28:2305-2314. [PMID: 34290396 PMCID: PMC8329281 DOI: 10.1038/s41418-021-00834-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/05/2021] [Accepted: 07/06/2021] [Indexed: 01/31/2023] Open
Abstract
The members of the Tumor Necrosis Factor (TNF) superfamily, the ligand lymphotoxin α1β2 (LTα1β2) and its unique receptor lymphotoxin β receptor (LTβR), play a pivotal role in the establishment and regulation of the immune system by allowing a tight communication between lymphocytes and stromal cells. Recent advances using transgenic mice harboring a specific deletion of the Ltbr gene in distinct stromal cells have revealed important roles for LTβR signaling in the thymic function that ensures the generation of a diverse and self-tolerant T-cell repertoire. In this review, we summarize our current knowledge on this signaling axis in the thymic homing of lymphoid progenitors and peripheral antigen-presenting cells, the trafficking and egress of thymocytes, the differentiation of medullary thymic epithelial cells, and the establishment of central tolerance. We also highlight the importance of LTα1β2/LTβR axis in controlling the recovery of the thymic function after myeloablative conditioning regimen, opening novel perspectives in regenerative medicine.
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Affiliation(s)
- Alexia Borelli
- grid.417850.f0000 0004 0639 5277Aix-Marseille University, CNRS, INSERM, CIML, Centre d’Immunologie de Marseille-Luminy, Marseille, France
| | - Magali Irla
- grid.417850.f0000 0004 0639 5277Aix-Marseille University, CNRS, INSERM, CIML, Centre d’Immunologie de Marseille-Luminy, Marseille, France
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5
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Xia H, Zhong S, Zhao Y, Ren B, Wang Z, Shi Y, Chai Q, Wang X, Zhu M. Thymic Egress Is Regulated by T Cell-Derived LTβR Signal and via Distinct Thymic Portal Endothelial Cells. Front Immunol 2021; 12:707404. [PMID: 34276703 PMCID: PMC8281811 DOI: 10.3389/fimmu.2021.707404] [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: 05/10/2021] [Accepted: 06/17/2021] [Indexed: 11/14/2022] Open
Abstract
Thymic blood vessels at the perivascular space (PVS) are the critical site for both homing of hematopoietic progenitor cells (HPCs) and egress of mature thymocytes. It has been intriguing how different opposite migrations can happen in the same place. A subset of specialized thymic portal endothelial cells (TPECs) associated with PVS has been identified to function as the entry site for HPCs. However, the cellular basis and mechanism underlying egress of mature thymocytes has not been well defined. In this study, using various conventional and conditional gene-deficient mouse models, we first confirmed the role of endothelial lymphotoxin beta receptor (LTβR) for thymic egress and ruled out the role of LTβR from epithelial cells or dendritic cells. In addition, we found that T cell-derived ligands lymphotoxin (LT) and LIGHT are required for thymic egress, suggesting a crosstalk between T cells and endothelial cells (ECs) for thymic egress control. Furthermore, immunofluorescence staining analysis interestingly showed that TPECs are also the exit site for mature thymocytes. Single-cell transcriptomic analysis of thymic endothelial cells suggested that TPECs are heterogeneous and can be further divided into two subsets depending on BST-1 expression level. Importantly, BST-1hi population is associated with thymic egressing thymocytes while BST-1lo/− population is associated with HPC settling. Thus, we have defined a LT/LIGHT-LTβR signaling–mediated cellular crosstalk regulating thymic egress and uncovered distinct subsets of TPECs controlling thymic homing and egress, respectively.
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Affiliation(s)
- Huan Xia
- Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of the Chinese Academy of Sciences, Beijing, China
| | - Suijuan Zhong
- State Key Laboratory of Cognitive Neuroscience and Learning, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yixiao Zhao
- Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of the Chinese Academy of Sciences, Beijing, China
| | - Boyang Ren
- Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of the Chinese Academy of Sciences, Beijing, China
| | - Zhongnan Wang
- Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yaoyao Shi
- Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Qian Chai
- Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Xiaoqun Wang
- State Key Laboratory of Cognitive Neuroscience and Learning, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Mingzhao Zhu
- Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of the Chinese Academy of Sciences, Beijing, China
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6
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Nitta T, Ota A, Iguchi T, Muro R, Takayanagi H. The fibroblast: An emerging key player in thymic T cell selection. Immunol Rev 2021; 302:68-85. [PMID: 34096078 PMCID: PMC8362222 DOI: 10.1111/imr.12985] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 05/04/2021] [Accepted: 05/08/2021] [Indexed: 02/06/2023]
Abstract
Fibroblasts have recently attracted attention as a key stromal component that controls the immune responses in lymphoid tissues. The thymus has a unique microenvironment comprised of a variety of stromal cells, including fibroblasts and thymic epithelial cells (TECs), the latter of which is known to be important for T cell development because of their ability to express self‐antigens. Thymic fibroblasts contribute to thymus organogenesis during embryogenesis and form the capsule and medullary reticular network in the adult thymus. However, the immunological significance of thymic fibroblasts has thus far only been poorly elucidated. In this review, we will summarize the current views on the development and functions of thymic fibroblasts as revealed by new technologies such as multicolor flow cytometry and single cell–based transcriptome profiling. Furthermore, the recently discovered role of medullary fibroblasts in the establishment of T cell tolerance by producing a unique set of self‐antigens will be highlighted.
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Affiliation(s)
- Takeshi Nitta
- Department of Immunology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Ayami Ota
- Department of Immunology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Takahiro Iguchi
- Department of Immunology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Ryunosuke Muro
- Department of Immunology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hiroshi Takayanagi
- Department of Immunology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
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7
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Nitta T, Takayanagi H. Non-Epithelial Thymic Stromal Cells: Unsung Heroes in Thymus Organogenesis and T Cell Development. Front Immunol 2021; 11:620894. [PMID: 33519827 PMCID: PMC7840694 DOI: 10.3389/fimmu.2020.620894] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Accepted: 11/27/2020] [Indexed: 12/16/2022] Open
Abstract
The stromal microenvironment in the thymus is essential for generating a functional T cell repertoire. Thymic epithelial cells (TECs) are numerically and phenotypically one of the most prominent stromal cell types in the thymus, and have been recognized as one of most unusual cell types in the body by virtue of their unique functions in the course of the positive and negative selection of developing T cells. In addition to TECs, there are other stromal cell types of mesenchymal origin, such as fibroblasts and endothelial cells. These mesenchymal stromal cells are not only components of the parenchymal and vascular architecture, but also have a pivotal role in controlling TEC development, although their functions have been less extensively explored than TECs. Here, we review both the historical studies on and recent advances in our understanding of the contribution of such non-TEC stromal cells to thymic organogenesis and T cell development. In particular, we highlight the recently discovered functional effect of thymic fibroblasts on T cell repertoire selection.
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Affiliation(s)
- Takeshi Nitta
- Department of Immunology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
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8
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Fibroblasts as a source of self-antigens for central immune tolerance. Nat Immunol 2020; 21:1172-1180. [PMID: 32839611 DOI: 10.1038/s41590-020-0756-8] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 07/02/2020] [Indexed: 12/13/2022]
Abstract
Fibroblasts are one of the most common but also neglected types of stromal cells, the heterogeneity of which underlies the specific function of tissue microenvironments in development and regeneration. In the thymus, autoreactive T cells are thought to be negatively selected by reference to the self-antigens expressed in medullary epithelial cells, but the contribution of other stromal cells to tolerance induction has been poorly examined. In the present study, we report a PDGFR+ gp38+ DPP4- thymic fibroblast subset that is required for T cell tolerance induction. The deletion of the lymphotoxin β-receptor in thymic fibroblasts caused an autoimmune phenotype with decreased expression of tissue-restricted and fibroblast-specific antigens, offering insight into the long-sought target of lymphotoxin signaling in the context of the regulation of autoimmunity. Thus, thymic medullary fibroblasts play an essential role in the establishment of central tolerance by producing a diverse array of self-antigens.
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9
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Giardino G, Borzacchiello C, De Luca M, Romano R, Prencipe R, Cirillo E, Pignata C. T-Cell Immunodeficiencies With Congenital Alterations of Thymic Development: Genes Implicated and Differential Immunological and Clinical Features. Front Immunol 2020; 11:1837. [PMID: 32922396 PMCID: PMC7457079 DOI: 10.3389/fimmu.2020.01837] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 07/08/2020] [Indexed: 02/06/2023] Open
Abstract
Combined Immunodeficiencies (CID) are rare congenital disorders characterized by defective T-cell development that may be associated with B- and NK-cell deficiency. They are usually due to alterations in genes expressed in hematopoietic precursors but in few cases, they are caused by impaired thymic development. Athymia was classically associated with DiGeorge Syndrome due to TBX1 gene haploinsufficiency. Other genes, implicated in thymic organogenesis include FOXN1, associated with Nude SCID syndrome, PAX1, associated with Otofaciocervical Syndrome type 2, and CHD7, one of the genes implicated in CHARGE syndrome. More recently, chromosome 2p11.2 microdeletion, causing FOXI3 haploinsufficiency, has been identified in 5 families with impaired thymus development. In this review, we will summarize the main genetic, clinical, and immunological features related to the abovementioned gene mutations. We will also focus on different therapeutic approaches to treat SCID in these patients.
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Affiliation(s)
- Giuliana Giardino
- Department of Translational Medical Sciences, Pediatric Section, Federico II University of Naples, Naples, Italy
| | - Carla Borzacchiello
- Department of Translational Medical Sciences, Pediatric Section, Federico II University of Naples, Naples, Italy
| | - Martina De Luca
- Department of Translational Medical Sciences, Pediatric Section, Federico II University of Naples, Naples, Italy
| | - Roberta Romano
- Department of Translational Medical Sciences, Pediatric Section, Federico II University of Naples, Naples, Italy
| | - Rosaria Prencipe
- Department of Translational Medical Sciences, Pediatric Section, Federico II University of Naples, Naples, Italy
| | - Emilia Cirillo
- Department of Translational Medical Sciences, Pediatric Section, Federico II University of Naples, Naples, Italy
| | - Claudio Pignata
- Department of Translational Medical Sciences, Pediatric Section, Federico II University of Naples, Naples, Italy
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10
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Alawam AS, Anderson G, Lucas B. Generation and Regeneration of Thymic Epithelial Cells. Front Immunol 2020; 11:858. [PMID: 32457758 PMCID: PMC7221188 DOI: 10.3389/fimmu.2020.00858] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 04/15/2020] [Indexed: 01/04/2023] Open
Abstract
The thymus is unique in its ability to support the maturation of phenotypically and functionally distinct T cell sub-lineages. Through its combined production of MHC-restricted conventional CD4+ and CD8+, and Foxp3+ regulatory T cells, as well as non-conventional CD1d-restricted iNKT cells and invariant γδT cells, the thymus represents an important orchestrator of immune system development and control. It is now clear that thymus function is largely determined by the availability of stromal microenvironments. These specialized areas emerge during thymus organogenesis and are maintained throughout life. They are formed from both epithelial and mesenchymal components, and collectively they support a stepwise program of thymocyte development. Of these stromal cells, cortical, and medullary thymic epithelial cells represent functional components of thymic microenvironments in both the cortex and medulla. Importantly, a key feature of thymus function is that levels of T cell production are not constant throughout life. Here, multiple physiological factors including aging, stress and pregnancy can have either short- or long-term detrimental impact on rates of thymus function. Here, we summarize our current understanding of the development and function of thymic epithelial cells, and relate this to strategies to protect and/or restore thymic epithelial cell function for therapeutic benefit.
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Affiliation(s)
- Abdullah S Alawam
- Institute for Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
| | - Graham Anderson
- Institute for Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
| | - Beth Lucas
- Institute for Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
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11
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Bhalla P, Wysocki CA, van Oers NSC. Molecular Insights Into the Causes of Human Thymic Hypoplasia With Animal Models. Front Immunol 2020; 11:830. [PMID: 32431714 PMCID: PMC7214791 DOI: 10.3389/fimmu.2020.00830] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 04/14/2020] [Indexed: 12/30/2022] Open
Abstract
22q11.2 deletion syndrome (DiGeorge), CHARGE syndrome, Nude/SCID and otofaciocervical syndrome type 2 (OTFCS2) are distinct clinical conditions in humans that can result in hypoplasia and occasionally, aplasia of the thymus. Thymic hypoplasia/aplasia is first suggested by absence or significantly reduced numbers of recent thymic emigrants, revealed in standard-of-care newborn screens for T cell receptor excision circles (TRECs). Subsequent clinical assessments will often indicate whether genetic mutations are causal to the low T cell output from the thymus. However, the molecular mechanisms leading to the thymic hypoplasia/aplasia in diverse human syndromes are not fully understood, partly because the problems of the thymus originate during embryogenesis. Rodent and Zebrafish models of these clinical syndromes have been used to better define the underlying basis of the clinical presentations. Results from these animal models are uncovering contributions of different cell types in the specification, differentiation, and expansion of the thymus. Cell populations such as epithelial cells, mesenchymal cells, endothelial cells, and thymocytes are variably affected depending on the human syndrome responsible for the thymic hypoplasia. In the current review, findings from the diverse animal models will be described in relation to the clinical phenotypes. Importantly, these results are suggesting new strategies for regenerating thymic tissue in patients with distinct congenital disorders.
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Affiliation(s)
- Pratibha Bhalla
- Department of Immunology, The University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Christian A. Wysocki
- Department of Pediatrics, The University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Nicolai S. C. van Oers
- Department of Immunology, The University of Texas Southwestern Medical Center, Dallas, TX, United States
- Department of Pediatrics, The University of Texas Southwestern Medical Center, Dallas, TX, United States
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX, United States
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12
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Lucas B, White AJ, Cosway EJ, Parnell SM, James KD, Jones ND, Ohigashi I, Takahama Y, Jenkinson WE, Anderson G. Diversity in medullary thymic epithelial cells controls the activity and availability of iNKT cells. Nat Commun 2020; 11:2198. [PMID: 32366944 PMCID: PMC7198500 DOI: 10.1038/s41467-020-16041-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 04/12/2020] [Indexed: 02/06/2023] Open
Abstract
The thymus supports multiple αβ T cell lineages that are functionally distinct, but mechanisms that control this multifaceted development are poorly understood. Here we examine medullary thymic epithelial cell (mTEC) heterogeneity and its influence on CD1d-restricted iNKT cells. We find three distinct mTEClow subsets distinguished by surface, intracellular and secreted molecules, and identify LTβR as a cell-autonomous controller of their development. Importantly, this mTEC heterogeneity enables the thymus to differentially control iNKT sublineages possessing distinct effector properties. mTEC expression of LTβR is essential for the development thymic tuft cells which regulate NKT2 via IL-25, while LTβR controls CD104+CCL21+ mTEClow that are capable of IL-15-transpresentation for regulating NKT1 and NKT17. Finally, mTECs regulate both iNKT-mediated activation of thymic dendritic cells, and iNKT availability in extrathymic sites. In conclusion, mTEC specialization controls intrathymic iNKT cell development and function, and determines iNKT pool size in peripheral tissues.
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Affiliation(s)
- Beth Lucas
- Institute for Immunology and Immunotherapy, University of Birmingham, Birmingham, B15 2TT, UK
| | - Andrea J White
- Institute for Immunology and Immunotherapy, University of Birmingham, Birmingham, B15 2TT, UK
| | - Emilie J Cosway
- Institute for Immunology and Immunotherapy, University of Birmingham, Birmingham, B15 2TT, UK
| | - Sonia M Parnell
- Institute for Immunology and Immunotherapy, University of Birmingham, Birmingham, B15 2TT, UK
| | - Kieran D James
- Institute for Immunology and Immunotherapy, University of Birmingham, Birmingham, B15 2TT, UK
| | - Nick D Jones
- Institute for Immunology and Immunotherapy, University of Birmingham, Birmingham, B15 2TT, UK
| | - Izumi Ohigashi
- Division of Experimental Immunology, Institute of Advanced Medical Sciences, University of Tokushima, Tokushima, 770-8503, Japan
| | - Yousuke Takahama
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - William E Jenkinson
- Institute for Immunology and Immunotherapy, University of Birmingham, Birmingham, B15 2TT, UK
| | - Graham Anderson
- Institute for Immunology and Immunotherapy, University of Birmingham, Birmingham, B15 2TT, UK.
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13
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Ribeiro C, Alves NL, Ferreirinha P. Medullary thymic epithelial cells: Deciphering the functional diversity beyond promiscuous gene expression. Immunol Lett 2019; 215:24-27. [PMID: 30853502 DOI: 10.1016/j.imlet.2019.01.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 01/28/2019] [Accepted: 01/30/2019] [Indexed: 12/27/2022]
Abstract
Within the thymus, cortical and medullary thymic epithelial cells (cTECs and mTECs, respectively) provide unique microenvironments for the development of T cells that are responsive to diverse foreign antigens while self-tolerant. Essential for tolerance induction, mTECs play a critical role in negative selection and T regulatory cell differentiation. In this article, we review the current knowledge on the functional diversity within mTECs and discuss how these novel subsets contribute to tolerance induction and are integrated in the complex blueprint of mTEC differentiation.
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Affiliation(s)
- Camila Ribeiro
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal
| | - Nuno L Alves
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal
| | - Pedro Ferreirinha
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal.
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14
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Montero-Herradón S, García-Ceca J, Zapata AG. Altered Maturation of Medullary TEC in EphB-Deficient Thymi Is Recovered by RANK Signaling Stimulation. Front Immunol 2018; 9:1020. [PMID: 29867988 PMCID: PMC5954084 DOI: 10.3389/fimmu.2018.01020] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 04/24/2018] [Indexed: 12/31/2022] Open
Abstract
In the present study, the relevance of EphB2 and EphB3 tyrosine kinase receptors for the maturation of medullary thymic epithelial cells (TECs) is analyzed. The absence of both molecules, but particularly that of EphB2, courses with altered maturation of medullary Cld3,4hiSSEA1+ epithelial progenitor cells, mature medulla epithelial cells, defined by the expression of specific cell markers, including UEA1, MHCII, CD40, CD80, and AIRE, and reduced expansion of medullary islets. In vivo assays demonstrate that these changes are a consequence of the absence of EphBs in both TECs and thymocytes. On the other hand, the changes, that remains in the adult thymus, correlated well with reduced proportions of E15.5 Vγ5+RANKL+ cells in EphB-deficient thymi that could result in decreased stimulation of RANK+ medullary TECs to mature, a fact that was confirmed by recovering of proportions of both CD40hiCD80+ and MHCIIhiUEA1+ mature medullary TECs of mutant E14.5 alymphoid thymic lobes by agonist anti-RANK antibody treatment. Accordingly, the effects of EphB deficiency on medullary TECs maturation are recovered by RANK stimulation.
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Affiliation(s)
- Sara Montero-Herradón
- Department of Cell Biology, Faculty of Biology, Complutense University of Madrid, Madrid, Spain
| | - Javier García-Ceca
- Department of Cell Biology, Faculty of Biology, Complutense University of Madrid, Madrid, Spain
| | - Agustín G Zapata
- Department of Cell Biology, Faculty of Biology, Complutense University of Madrid, Madrid, Spain
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RelB intrinsically regulates the development and function of medullary thymic epithelial cells. SCIENCE CHINA-LIFE SCIENCES 2018; 61:1039-1048. [PMID: 29730722 DOI: 10.1007/s11427-017-9298-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Accepted: 03/08/2018] [Indexed: 12/24/2022]
Abstract
Medullary thymic epithelial cells (mTECs) act as one of the major stromal components in the thymus for selection and maturation of both conventional T cells and non-conventional T cells. Extensive efforts have been spent to understand how mTEC development and function are regulated. Although RelB has been well accepted to be a critical transcriptional factor for mTEC development, the underlying mechanisms still remain largely unclear. In this study, by generating thymic epithelial cell specific RelB deficient mice, we found that epithelial intrinsic RelB is required for mTEC homeostatic proliferation. Mechanistically, RelB regulates the expression of genes involved in cell cycle. Functionally, lack of intrinsic RelB in thymic epithelial cells results in dramatically reduced population of mTECs and impaired development of thymic invariant natural killer T (iNKT) cells and intraepithelial lymphocyte precursors (IELPs). This study thus reveals an epithelial intrinsic role of RelB on mTEC development and function.
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16
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Xiao X, Putatunda R, Zhang Y, Soni PV, Li F, Zhang T, Xin M, Luo JJ, Bethea JR, Cheng Y, Hu W. Lymphotoxin β receptor-mediated NFκB signaling promotes glial lineage differentiation and inhibits neuronal lineage differentiation in mouse brain neural stem/progenitor cells. J Neuroinflammation 2018; 15:49. [PMID: 29463313 PMCID: PMC5819232 DOI: 10.1186/s12974-018-1074-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 01/22/2018] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Lymphotoxin (LT) is a lymphokine mainly expressed in lymphocytes. LTα binds one or two membrane-associated LTβ to form LTα2β1 or LTα1β2 heterotrimers. The predominant LTα1β2 binds to LTβ receptor (LTβR) primarily expressed in epithelial and stromal cells. Most studies on LTβR signaling have focused on the organization, development, and maintenance of lymphoid tissues. However, the roles of LTβR signaling in the nervous system, particularly in neurogenesis, remain unknown. Here, we investigated the role of LTβR-mediated NFκB signaling in regulating neural lineage differentiation. METHODS The C57BL/6J wild-type and GFAP-dnIκBα transgenic mice were used. Serum-free embryoid bodies were cultured from mouse embryonic stem cells and further induced into neural stem/progenitor cells (NSCs/NPCs). Primary neurospheres were cultured from embryonic and adult mouse brains followed by monolayer culture for amplification/passage. NFκB activation was determined by adenovirus-mediated NFκB-firefly-luciferase reporter assay and p65/RelB/p52 nuclear translocation assay. LTβR mRNA expression was evaluated by quantitative RT-PCR and LTβR protein expression was determined by immunohistochemistry and Western blot analysis. Multilabeled immunocytochemistry or immunohistochemistry followed by fluorescent confocal microscopy and quantitative analysis of neural lineage differentiation were performed. Graphing and statistical analysis were performed with GraphPad Prism software. RESULTS In cultured NSCs/NPCs, LTα1β2 stimulation induced an activation of classical and non-classical NFκB signaling. The expression of LTβR-like immunoreactivity in GFAP+/Sox2+ NSCs was identified in well-established neurogenic zones of adult mouse brain. Quantitative RT-PCR and Western blot analysis validated the expression of LTβR in cultured NSCs/NPCs and brain neurogenic regions. LTβR expression was significantly increased during neural induction. LTα1β2 stimulation in cultured NSCs/NPCs promoted astroglial and oligodendrocytic lineage differentiation, but inhibited neuronal lineage differentiation. Astroglial NFκB inactivation in GFAP-dnIκBα transgenic mice rescued LTβR-mediated abnormal phenotypes of cultured NSCs/NPCs. CONCLUSION This study provides the first evidence for the expression and function of LTβR signaling in NSCs/NPCs. Activation of LTβR signaling promotes glial lineage differentiation. Our results suggest that neurogenesis is regulated by the adaptive immunity and inflammatory responses.
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Affiliation(s)
- Xiao Xiao
- Department of Neurosurgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, 400010, China
- Center for Metabolic Disease Research, Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, 3500 N Broad Street, Philadelphia, PA, 19140, USA
| | - Raj Putatunda
- Center for Metabolic Disease Research, Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, 3500 N Broad Street, Philadelphia, PA, 19140, USA
| | - Yonggang Zhang
- Center for Metabolic Disease Research, Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, 3500 N Broad Street, Philadelphia, PA, 19140, USA
| | - Priya V Soni
- Center for Metabolic Disease Research, Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, 3500 N Broad Street, Philadelphia, PA, 19140, USA
| | - Fang Li
- Center for Metabolic Disease Research, Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, 3500 N Broad Street, Philadelphia, PA, 19140, USA
| | - Ting Zhang
- Center for Metabolic Disease Research, Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, 3500 N Broad Street, Philadelphia, PA, 19140, USA
| | - Mingyang Xin
- Center for Metabolic Disease Research, Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, 3500 N Broad Street, Philadelphia, PA, 19140, USA
| | - Jin Jun Luo
- Department of Neurology, Temple University Lewis Katz School of Medicine, 3401 N Broad Street, Philadelphia, PA, USA
| | - John R Bethea
- Department of Biology, Drexel University, Philadelphia, PA, USA
| | - Yuan Cheng
- Department of Neurosurgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, 400010, China.
| | - Wenhui Hu
- Center for Metabolic Disease Research, Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, 3500 N Broad Street, Philadelphia, PA, 19140, USA.
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17
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Cosway EJ, Lucas B, James KD, Parnell SM, Carvalho-Gaspar M, White AJ, Tumanov AV, Jenkinson WE, Anderson G. Redefining thymus medulla specialization for central tolerance. J Exp Med 2017; 214:3183-3195. [PMID: 28830910 PMCID: PMC5679166 DOI: 10.1084/jem.20171000] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 07/12/2017] [Accepted: 08/01/2017] [Indexed: 12/27/2022] Open
Abstract
During αβT cell development, the thymus medulla represents an essential microenvironment for T cell tolerance. This functional specialization is attributed to its typical organized topology consisting of a branching structure that contains medullary thymic epithelial cell (mTEC) networks to support negative selection and Foxp3+ T-regulatory cell (T-reg) development. Here, by performing TEC-specific deletion of the thymus medulla regulator lymphotoxin β receptor (LTβR), we show that thymic tolerance mechanisms operate independently of LTβR-mediated mTEC development and organization. Consistent with this, mTECs continue to express Fezf2 and Aire, regulators of intrathymic self-antigens, and support T-reg development despite loss of LTβR-mediated medulla organogenesis. Moreover, we demonstrate that LTβR controls thymic tolerance by regulating the frequency and makeup of intrathymic dendritic cells (DCs) required for effective thymocyte negative selection. In all, our study demonstrates that thymus medulla specialization for thymic tolerance segregates from medulla organogenesis and instead involves LTβR-mediated regulation of the thymic DC pool.
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Affiliation(s)
- Emilie J Cosway
- Institute for Immunology and Immunotherapy, College of Medical and Dental Sciences, Medical School, University of Birmingham, Birmingham, England, UK
| | - Beth Lucas
- Institute for Immunology and Immunotherapy, College of Medical and Dental Sciences, Medical School, University of Birmingham, Birmingham, England, UK
| | - Kieran D James
- Institute for Immunology and Immunotherapy, College of Medical and Dental Sciences, Medical School, University of Birmingham, Birmingham, England, UK
| | - Sonia M Parnell
- Institute for Immunology and Immunotherapy, College of Medical and Dental Sciences, Medical School, University of Birmingham, Birmingham, England, UK
| | - Manuela Carvalho-Gaspar
- Institute for Immunology and Immunotherapy, College of Medical and Dental Sciences, Medical School, University of Birmingham, Birmingham, England, UK
| | - Andrea J White
- Institute for Immunology and Immunotherapy, College of Medical and Dental Sciences, Medical School, University of Birmingham, Birmingham, England, UK
| | - Alexei V Tumanov
- Department of Microbiology, Immunology, and Molecular Genetics, University of Texas Health Science Center at San Antonio, San Antonio, TX
| | - William E Jenkinson
- Institute for Immunology and Immunotherapy, College of Medical and Dental Sciences, Medical School, University of Birmingham, Birmingham, England, UK
| | - Graham Anderson
- Institute for Immunology and Immunotherapy, College of Medical and Dental Sciences, Medical School, University of Birmingham, Birmingham, England, UK
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