1
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Wang L, Jing L, Zhang Q, Li S, Wang Y, Zhao H. Lead induced thymic immunosuppression in Japanese quail (Coturnix japonica) via oxidative stress-based T cell receptor pathway signaling inhibition. J Inorg Biochem 2022; 235:111950. [DOI: 10.1016/j.jinorgbio.2022.111950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 07/24/2022] [Accepted: 07/26/2022] [Indexed: 11/28/2022]
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2
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Coder BD, Wang H, Ruan L, Su DM. Thymic involution perturbs negative selection leading to autoreactive T cells that induce chronic inflammation. THE JOURNAL OF IMMUNOLOGY 2015; 194:5825-37. [PMID: 25957168 DOI: 10.4049/jimmunol.1500082] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 04/14/2015] [Indexed: 12/22/2022]
Abstract
Thymic involution and the subsequent amplified release of autoreactive T cells increase the susceptibility toward developing autoimmunity, but whether they induce chronic inflammation with advanced age remains unclear. The presence of chronic low-level proinflammatory factors in elderly individuals (termed inflammaging) is a significant risk factor for morbidity and mortality in virtually every chronic age-related disease. To determine how thymic involution leads to the persistent release and activation of autoreactive T cells capable of inducing inflammaging, we used a Foxn1 conditional knockout mouse model that induces accelerated thymic involution while maintaining a young periphery. We found that thymic involution leads to T cell activation shortly after thymic egress, which is accompanied by a chronic inflammatory phenotype consisting of cellular infiltration into non-lymphoid tissues, increased TNF-α production, and elevated serum IL-6. Autoreactive T cell clones were detected in the periphery of Foxn1 conditional knockout mice. A failure of negative selection, facilitated by decreased expression of Aire rather than impaired regulatory T cell generation, led to autoreactive T cell generation. Furthermore, the young environment can reverse age-related regulatory T cell accumulation in naturally aged mice, but not inflammatory infiltration. Taken together, these findings identify thymic involution and the persistent activation of autoreactive T cells as a contributing source of chronic inflammation (inflammaging).
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Affiliation(s)
- Brandon D Coder
- Department of Cell Biology and Immunology, University of North Texas Health Science Center at Fort Worth, Fort Worth, TX 76107
| | - Hongjun Wang
- Department of Cell Biology and Immunology, University of North Texas Health Science Center at Fort Worth, Fort Worth, TX 76107
| | - Linhui Ruan
- Department of Cell Biology and Immunology, University of North Texas Health Science Center at Fort Worth, Fort Worth, TX 76107
| | - Dong-Ming Su
- Department of Cell Biology and Immunology, University of North Texas Health Science Center at Fort Worth, Fort Worth, TX 76107
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3
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Franckaert D, Schlenner SM, Heirman N, Gill J, Skogberg G, Ekwall O, Put K, Linterman MA, Dooley J, Liston A. Premature thymic involution is independent of structural plasticity of the thymic stroma. Eur J Immunol 2015; 45:1535-47. [PMID: 25627671 PMCID: PMC4670717 DOI: 10.1002/eji.201445277] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 12/22/2014] [Accepted: 01/23/2015] [Indexed: 12/14/2022]
Abstract
The thymus is the organ devoted to T-cell production. The thymus undergoes multiple rounds of atrophy and redevelopment before degenerating with age in a process known as involution. This process is poorly understood, despite the influence the phenomenon has on peripheral T-cell numbers. Here we have investigated the FVB/N mouse strain, which displays premature thymic involution. We find multiple architectural and cellular features that precede thymic involution, including disruption of the epithelial–endothelial relationship and a progressive loss of pro-T cells. The architectural features, reminiscent of the human thymus, are intrinsic to the nonhematopoietic compartment and are neither necessary nor sufficient for thymic involution. By contrast, the loss of pro-T cells is intrinsic to the hematopoietic compartment, and is sufficient to drive premature involution. These results identify pro-T-cell loss as the main driver of premature thymic involution, and highlight the plasticity of the thymic stroma, capable of maintaining function across diverse interstrain architectures.
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Affiliation(s)
- Dean Franckaert
- Autoimmune Genetics Laboratory, VIB, Leuven, Belgium.,Department of Microbiology and Immunology, University of Leuven, Leuven, Belgium
| | - Susan M Schlenner
- Autoimmune Genetics Laboratory, VIB, Leuven, Belgium.,Department of Microbiology and Immunology, University of Leuven, Leuven, Belgium
| | - Nathalie Heirman
- Autoimmune Genetics Laboratory, VIB, Leuven, Belgium.,Department of Microbiology and Immunology, University of Leuven, Leuven, Belgium
| | - Jason Gill
- Mechanisms of Cancer, Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Gabriel Skogberg
- Department of Rheumatology and Inflammation Research, Göteborg University, Gothenburg, Sweden
| | - Olov Ekwall
- Department of Rheumatology and Inflammation Research, Göteborg University, Gothenburg, Sweden
| | - Karen Put
- Autoimmune Genetics Laboratory, VIB, Leuven, Belgium.,Department of Microbiology and Immunology, University of Leuven, Leuven, Belgium
| | | | - James Dooley
- Autoimmune Genetics Laboratory, VIB, Leuven, Belgium.,Department of Microbiology and Immunology, University of Leuven, Leuven, Belgium
| | - Adrian Liston
- Autoimmune Genetics Laboratory, VIB, Leuven, Belgium
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4
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Smeets MFMA, Wiest DL, Izon DJ. Fli-1 regulates the DN2 to DN3 thymocyte transition and promotes γδ T-cell commitment by enhancing TCR signal strength. Eur J Immunol 2014; 44:2617-24. [PMID: 24935715 PMCID: PMC5242326 DOI: 10.1002/eji.201444442] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2014] [Revised: 05/22/2014] [Accepted: 06/10/2014] [Indexed: 01/05/2023]
Abstract
Friend leukemia integration 1 (Fli-1) is a member of the Ets transcription factor family and is expressed during T-cell development; however, the role Fli-1 plays in early T-cell differentiation has not been elucidated. In this report, we demonstrate that in mouse, Fli-1 overexpression retards the CD4(-) CD8(-) double-negative (DN) to CD4(+) CD8(+) double-positive (DP) transition by deregulating normal DN thymocyte development. Specifically, Fli-1 expression moderates the DN2 and DN3 developmental transitions. We further show that Fli-1 overexpression partially mimics strong TCR signals in developing DN thymocytes and thereby enhances γδ T-cell development. Conversely, Fli-1 knockdown by small hairpin RNA reverses the lineage bias from γδ T cells and directs DN cells to the αβ lineage by attenuating TCR signaling. Therefore, Fli-1 plays a critical role in both the DN2 to DN3 transition and αβ/γδ lineage commitment.
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MESH Headings
- Animals
- Cells, Cultured
- Mice
- Proto-Oncogene Protein c-fli-1/genetics
- Proto-Oncogene Protein c-fli-1/immunology
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- Receptors, Antigen, T-Cell, gamma-delta/genetics
- Receptors, Antigen, T-Cell, gamma-delta/immunology
- Signal Transduction/genetics
- Signal Transduction/immunology
- T-Lymphocytes/cytology
- T-Lymphocytes/immunology
- Thymocytes/cytology
- Thymocytes/immunology
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Affiliation(s)
- Monique F M A Smeets
- Haematology and Leukaemia Unit, St. Vincent's Institute, Fitzroy, Victoria, Australia
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5
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Jung WS, Han SM, Kim SM, Kim ME, Lee JS, Seo KW, Youn HY, Lee HW. Stimulatory effect of HGF-overexpressing adipose tissue-derived mesenchymal stem cells on thymus regeneration in a rat thymus involution model. Cell Biol Int 2014; 38:1106-17. [DOI: 10.1002/cbin.10306] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 04/14/2014] [Indexed: 01/07/2023]
Affiliation(s)
- Woo-Sung Jung
- Department of Veterinary Internal Medicine, College of Veterinary Medicine; Seoul National University; 1 Gwanak-ro Gwanak-gu Seoul 151-742 Republic of Korea
| | - Sei-Myoung Han
- Department of Veterinary Internal Medicine, College of Veterinary Medicine; Seoul National University; 1 Gwanak-ro Gwanak-gu Seoul 151-742 Republic of Korea
| | - Sung-Min Kim
- Division of Magnetic Resonance Research; Korea Basic Science Institute; Ochang Chungbuk Republic of Korea
| | - Mi-Eun Kim
- Department of Biology, College of Natural Sciences; Chosun University; Gwangju Republic of Korea
| | - Jun-Sik Lee
- Department of Biology, College of Natural Sciences; Chosun University; Gwangju Republic of Korea
| | - Kyoung-Won Seo
- Department of Veterinary Internal Medicine, College of Veterinary Medicine; Chungnam National University; 99 Daehakro Yuseoung gu Daejon 305-764 Republic of Korea
| | - Hwa-Young Youn
- Department of Veterinary Internal Medicine, College of Veterinary Medicine; Seoul National University; 1 Gwanak-ro Gwanak-gu Seoul 151-742 Republic of Korea
- Research Institute for Veterinary Science, College of Veterinary Medicine; Seoul National University; 1 Gwanak-ro Gwanak-gu Seoul 151-742 Republic of Korea
| | - Hee-Woo Lee
- Research Institute for Veterinary Science, College of Veterinary Medicine; Seoul National University; 1 Gwanak-ro Gwanak-gu Seoul 151-742 Republic of Korea
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6
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Mignini F, Sabbatini M, Mattioli L, Cosenza M, Artico M, Cavallotti C. Neuro-immune modulation of the thymus microenvironment (review). Int J Mol Med 2014; 33:1392-400. [PMID: 24676230 DOI: 10.3892/ijmm.2014.1709] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 02/13/2014] [Indexed: 11/05/2022] Open
Abstract
The thymus is the primary site for T-cell lympho-poiesis. Its function includes the maturation and selection of antigen specific T cells and selective release of these cells to the periphery. These highly complex processes require precise parenchymal organization and compartmentation where a plethora of signalling pathways occur, performing strict control on the maturation and selection processes of T lymphocytes. In this review, the main morphological characteristics of the thymus microenvironment, with particular emphasis on nerve fibers and neuropeptides were assessed, as both are responsible for neuro-immune‑modulation functions. Among several neurotransmitters that affect thymus function, we highlight the dopaminergic system as only recently has its importance on thymus function and lymphocyte physiology come to light.
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Affiliation(s)
- Fiorenzo Mignini
- Human Anatomy, School of Drug and Health Products Science, University of Camerino, Ι-62032 Camerino, Italy
| | - Maurizio Sabbatini
- Human Anatomy, Department of Health Sciences, University of Eastern Piedmont ̔Amedeo Avogadro̓, I-28100 Novara, Italy
| | - Laura Mattioli
- Human Anatomy, School of Drug and Health Products Science, University of Camerino, Ι-62032 Camerino, Italy
| | - Monica Cosenza
- Human Anatomy, School of Drug and Health Products Science, University of Camerino, Ι-62032 Camerino, Italy
| | - Marco Artico
- Department of Anatomical, Histological, Medico-legal and Locomotor System Sciences, Sapienza University of Rome, Ι-00185 Rome, Italy
| | - Carlo Cavallotti
- Department of Sensory Organs, Sapienza University of Rome, Ι-00185 Rome, Italy
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7
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Li D, Ye Y, Deng L, Ma H, Fan X, Zhang Y, Yan H, Deng X, Li Y, Ma Y. Gene expression profiling analysis of deoxynivalenol-induced inhibition of mouse thymic epithelial cell proliferation. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2013; 36:557-566. [PMID: 23827195 DOI: 10.1016/j.etap.2013.06.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2013] [Revised: 06/02/2013] [Accepted: 06/05/2013] [Indexed: 06/02/2023]
Abstract
Deoxynivalenol (DON) is a mycotoxin produced as a secondary metabolite by fungal species. It has been shown that DON has serious toxic effects on many kinds of immune cells. However, the toxic effects on thymic epithelial cells were poorly understood. The purpose of this study is to investigate the gene expression differences for the DON-induced inhibition on the proliferation of mouse thymic epithelial cell line 1 (MTEC1). After the experiments of cell viability, morphological investigation and cell cycle analysis, microarray analysis was carried out. The differentially expressed genes belong to a variety of functional categories, including genes involved in metabolic process, cell cycle, oxidation-reduction process and apoptosis. Our results provide molecular insights into the gene expression differences of DON-induced toxic effects and suggest that p53 signaling pathway may play an important role in the inhibition of MTEC1 cell proliferation.
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Affiliation(s)
- Daotong Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Yaqiong Ye
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Li Deng
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Haoran Ma
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Xiaolong Fan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Yuan Zhang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Haikuo Yan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Xianbo Deng
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Yugu Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Yongjiang Ma
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.
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8
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Smeets MFMA, Mackenzie-Kludas C, Mohtashami M, Zhang HH, Zúñiga-Pflücker JC, Izon DJ. Removal of myeloid cytokines from the cellular environment enhances T-cell development in vitro. Int Immunol 2013; 25:589-99. [DOI: 10.1093/intimm/dxt025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
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9
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Smeets MFMA, Chan AC, Dagger S, Bradley CK, Wei A, Izon DJ. Fli-1 overexpression in hematopoietic progenitors deregulates T cell development and induces pre-T cell lymphoblastic leukaemia/lymphoma. PLoS One 2013; 8:e62346. [PMID: 23667468 PMCID: PMC3646842 DOI: 10.1371/journal.pone.0062346] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 03/20/2013] [Indexed: 12/28/2022] Open
Abstract
The Ets transcription factor Fli-1 is preferentially expressed in hematopoietic tissues and cells, including immature T cells, but the role of Fli-1 in T cell development has not been closely examined. To address this we retrovirally overexpressed Fli-1 in various in vitro and in vivo settings and analysed its effect on T cell development. We found that Fli-1 overexpression perturbed the DN to DP transition and inhibited CD4 development whilst enhancing CD8 development both in vitro and in vivo. Surprisingly, Fli-1 overexpression in vivo eventuated in development of pre-T cell lymphoblastic leukaemia/lymphoma (pre-T LBL). Known Fli-1 target genes such as the pro-survival Bcl-2 family members were not found to be upregulated. In contrast, we found increased NOTCH1 expression in all Fli-1 T cells and detected Notch1 mutations in all tumours. These data show a novel function for Fli-1 in T cell development and leukaemogenesis and provide a new mouse model of pre-T LBL to identify treatment options that target the Fli-1 and Notch1 signalling pathways.
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Affiliation(s)
- Monique F. M. A. Smeets
- Haematology and Leukaemia Unit, St. Vincent’s Institute, University of Melbourne, Fitzroy, Victoria, Australia
| | - Angela C. Chan
- Department of Microbiology and Immunology, University of Melbourne, Parkville, Victoria, Australia
| | - Samantha Dagger
- School of Pathology and Laboratory Medicine, University of Western Australia, Crawley, Western Australia, Australia
| | | | - Andrew Wei
- Department of Clinical Haematology, The Alfred Hospital and The Australian Centre for Blood Diseases, Monash University, Melbourne, Victoria, Australia
| | - David J. Izon
- Haematology and Leukaemia Unit, St. Vincent’s Institute, University of Melbourne, Fitzroy, Victoria, Australia
- * E-mail:
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10
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Lai KP, Lai JJ, Chang P, Altuwaijri S, Hsu JW, Chuang KH, Shyr CR, Yeh S, Chang C. Targeting thymic epithelia AR enhances T-cell reconstitution and bone marrow transplant grafting efficacy. Mol Endocrinol 2012; 27:25-37. [PMID: 23250486 DOI: 10.1210/me.2012-1244] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Although thymic involution has been linked to the increased testosterone in males after puberty, its detailed mechanism and clinical application related to T-cell reconstitution in bone marrow transplantation (BMT) remain unclear. By performing studies with reciprocal BMT and cell-specific androgen receptor (AR) knockout mice, we found that AR in thymic epithelial cells, but not thymocytes or fibroblasts, played a more critical role to determine thymic cellularity. Further dissecting the mechanism using cell-specific thymic epithelial cell-AR knockout mice bearing T-cell receptor transgene revealed that elevating thymocyte survival was due to the enhancement of positive selection resulting in increased positively selected T-cells in both male and female mice. Targeting AR, instead of androgens, either via genetic knockout of thymic epithelial AR or using an AR-degradation enhancer (ASC-J9®), led to increased BMT grafting efficacy, which may provide a new therapeutic approach to boost T-cell reconstitution in the future.
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Affiliation(s)
- Kuo-Pao Lai
- George H Whipple Laboratory for Cancer Research, University of Rochester Medical Center, Rochester, New York 14642, USA
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11
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Regulatory role of mouse epidermal growth factor-like protein 8 in thymic epithelial cells. Biochem Biophys Res Commun 2012; 425:250-5. [DOI: 10.1016/j.bbrc.2012.07.076] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Accepted: 07/16/2012] [Indexed: 01/27/2023]
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12
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Lin'kova NS, Polyakova VO, Trofimov AV, Kvetnoy IM, Khavinson VK. Peptidergic regulation of thymocyte differentiation, proliferation, and apoptosis during aging of the thymus. Bull Exp Biol Med 2012; 151:239-42. [PMID: 22238759 DOI: 10.1007/s10517-011-1298-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The effects of T-31, AB-17, and AB-9 peptides on old (passage 8) thymocyte culture were studied. Only AB-9 peptide exhibited a complex geroprotective effect on thymocytes during their aging. Peptide AB-9 stimulated proliferative activity and differentiation of thymocytes and inhibited their apoptosis.
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Affiliation(s)
- N S Lin'kova
- St. Petersburg Institute of Bioregulation and Gerontology, North Western Division of Russian Academy of Medical Sciences, Russia.
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13
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Koçkaya EA, Kılıç A, Karacaoğlu E, Selmanoğlu G. Does furan affect the thymus in growing male rats? Drug Chem Toxicol 2012; 35:316-23. [PMID: 22289615 DOI: 10.3109/01480545.2011.619191] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Furan has been identified in foods such as heat-treated foods, including coffee, canned meat, hazelnuts, and infant foods and formulas. Children may be exposed to furan via either consumption of these foods or their derivatives. We evaluated the effects of furan on the thymus of weaning male rats in the present study. Five separate groups containing male rats were used: control, oil control, and three furan-treated groups. Furan was given orally to rats in the treatment groups at doses of 2, 4, and 8 mg/kg/day for 90 days. At the end of the experiment, thymus of the rats were examined morphologically, histopathologically, and immunohistochemically. We observed that absolute and relative weights of thymus were decreased significantly in rats treated with 4- and 8-mg/kg/day doses of furan. In histopathological examination, enlargement of interstitial connective tissue between the thymic lobules, lymphocyte depletion, and hemorrhage were observed. We detected an increase in apoptotic cell counts in thymus of the treatment groups. In addition, we found significant differences in the distribution of fibronectin and transforming growth factor-beta in the thymus of the treatment groups. In conclusion, we suggest that furan has affected the thymus in growing male rats.
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Affiliation(s)
- E Arzu Koçkaya
- The Higher Vocational School of Health Services, Gazi University, Ankara, Turkey.
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14
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Overexpression of Foxn1 attenuates age-associated thymic involution and prevents the expansion of peripheral CD4 memory T cells. Blood 2011; 118:5723-31. [PMID: 21908422 DOI: 10.1182/blood-2011-03-342097] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The forkhead box n1 (Foxn1) transcription factor is essential for thymic organogenesis during embryonic development; however, a functional role of Foxn1 in the postnatal thymus is less well understood. We developed Foxn1 transgenic mice (Foxn1Tg), in which overexpression of Foxn1 is driven by the human keratin-14 promoter. Expression of the Foxn1 transgene increased the endogenous Foxn1 levels. In aged mice, overexpression of Foxn1 in the thymus attenuated the decline in thymocyte numbers, prevented the decline in frequency of early thymic progenitors, and generated a higher number of signal joint TCR excised circle. Histologic studies revealed that structural alterations associated with thymic involution were diminished in aged Foxn1 Tg. Total numbers of EpCAM+ MHC II+ and MHC II(hi) thymic epithelial cells were higher in young and old Foxn1Tg and more EpCAM+ MHC II(hi) TEC expressed Ki-67 in aged Foxn1Tg compared with WT. Furthermore, Foxn1Tg displayed a significant reduction in the expansion of splenic CD4+ memory compartments and attenuated the decline in CD4+ and CD8+ naive compartments. Our data indicate that manipulation of Foxn1 expression in the thymus ameliorates thymopoiesis in aged mice and offer a strategy to combat the age-associated decline in naive T-cell production and CD4 naive/memory ratios in the elderly.
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15
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Dorko F, Kluchová D, Boleková A, Spakovská T, Borošová T, Lovasová K. Influence of surgical and chemical orchidectomy on weight and distribution of AChE-nerve fibres in thymuses of adult rats. Eur J Histochem 2011; 55:e22. [PMID: 22073369 PMCID: PMC3203471 DOI: 10.4081/ejh.2011.e22] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2010] [Accepted: 05/15/2011] [Indexed: 11/23/2022] Open
Abstract
The thymus is a crossroad between the immune and neuroendocrine systems. As such, it is innervated by acetylcholinesterase (AChE)-positive fibres of the vagus, the recurrent laryngeal and the phrenic nerves. It is well know, that the innervations density of the thymus increases with age. In our study, adult rats were orchidectomized (surgically and chemically by the application of a luteinizing hormone-releasing hormone). The density of AChE-positive nerve fibres in thymuses, as well as the weight of thymuses was examined. The authors found that both surgical and chemical orchidectomy result in macroscopic and microscopic regeneration of the atrophied thymuses. In regenerated rat’s thymuses after orchidectomy the density of AChE-positive nerve fibres was markedly higher in comparison with the control animals. The distribution, as well as the density of AChE-positive nerve fibres in regenerated thymuses after orchidectomy evokes the images of its innervations like in young animals before age-related involution. The authors also found a markedly higher weight of thymuses of orchidectomized rats in comparison with the control groups. In recent study the authors proved that after 8 weeks surgical orchidectomy leads to the regeneration of thymic AChE-positive innervation and chemical orchidectomy by administration of luteinizing hormone-releasing hormone after 4 weeks of adult rats.
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Affiliation(s)
- F Dorko
- Department of Anatomy, Faculty of Medicine, P.J. Šafárik University in Košice, Slovakia.
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16
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Xenogenic cardiomyocytes transplantation for the treatment of curing acute myocardial infarction. Biologia (Bratisl) 2011. [DOI: 10.2478/s11756-011-0043-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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17
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Flomerfelt FA, El Kassar N, Gurunathan C, Chua KS, League SC, Schmitz S, Gershon TR, Kapoor V, Yan XY, Schwartz RH, Gress RE. Tbata modulates thymic stromal cell proliferation and thymus function. ACTA ACUST UNITED AC 2010; 207:2521-32. [PMID: 20937703 PMCID: PMC2964569 DOI: 10.1084/jem.20092759] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Niche availability provided by stromal cells is critical to thymus function. Thymi with diminished function contain fewer stromal cells, whereas thymi with robust function contain proliferating stromal cell populations. Here, we show that the thymus, brain, and testes-associated gene (Tbata; also known as SPATIAL) regulates thymic epithelial cell (TEC) proliferation and thymus size. Tbata is expressed in thymic stromal cells and interacts with the enzyme Uba3, thereby inhibiting the Nedd8 pathway and cell proliferation. Thymi from aged Tbata-deficient mice are larger and contain more dividing TECs than wild-type littermate controls. In addition, thymic reconstitution after bone marrow transplantation occurred more rapidly in Rag2(-/-)Tbata(-/-) mice than in Rag2(-/-)Tbata(+/+) littermate controls. These findings suggest that Tbata modulates thymus function by regulating stromal cell proliferation via the Nedd8 pathway.
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Affiliation(s)
- Francis A Flomerfelt
- Experimental Transplantation Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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18
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Carrio R, Altman NH, Lopez DM. Downregulation of interleukin-7 and hepatocyte growth factor in the thymic microenvironment is associated with thymus involution in tumor-bearing mice. Cancer Immunol Immunother 2009; 58:2059-72. [PMID: 19421751 PMCID: PMC11030654 DOI: 10.1007/s00262-009-0714-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2008] [Accepted: 04/17/2009] [Indexed: 12/18/2022]
Abstract
During mammary tumorigenesis, there is a profound thymic involution associated with severe depletion of the most abundant subset of thymocytes, CD4(+)CD8(+) immature cells, and an early arrest in at least two steps of T cell differentiation. Thymic atrophy that is normally related with aging has been observed in other model systems, including graft-vs-host disease (GVHD) and tumor development. However, the mechanisms involved in this phenomenon remain to be elucidated. Vascular endothelial growth factor (VEGF) has been associated with thymic involution, when expressed at high levels systemically. In thymuses of D1-DMBA-3 tumor-bearing mice, this growth factor is diminished relative to the level of normal thymuses. Interestingly, the expression of hepatocyte growth factor (HGF), which has been associated with proliferation, cell survival, angiogenesis and B-cell differentiation, is profoundly down-regulated in thymuses of tumor bearers. In parallel, IL-7 and IL-15 mRNA, crucial cytokines involved in thymocytes development and cellular homeostasis, respectively, are also down-regulated in the thymuses of tumor hosts as compared to those of normal mice. Injection of HGF into mice implanted with mammary tumors resulted in normalization of thymic volume and levels of VEGF, IL-7 and IL-15. While, injections of IL-7 partially restored the thymic involution observed in the thymuses of tumor-bearing mice, injection of IL-15 did not have any significant effects. Our data suggest that the downregulation of HGF and IL-7 may play an important role in the thymic involution observed in tumor-bearing hosts.
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Affiliation(s)
- Roberto Carrio
- Department of Microbiology and Immunology, Miller School of Medicine, University of Miami, P.O. Box 016960, Miami, FL 33101 USA
| | - Norman H. Altman
- Department of Pathology, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | - Diana M. Lopez
- Department of Microbiology and Immunology, Miller School of Medicine, University of Miami, P.O. Box 016960, Miami, FL 33101 USA
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Gat LL, Gogat K, Van Den Berghe L, Brizard M, Kobetz A, Marchant D, Abitbol M, Ménasche M. The β3 Integrin Gene is Expressed at High Levels in the Major Haematopoietic and Lymphoid Organs, Vascular System, and Skeleton During Mouse Embryo Development. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/cac.10.3.129.140] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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20
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Melnikova VI, Afanasieva MA, Dmitrieva SB, Karpova YD, Sharova NP, Zakharova LA. Immune proteasomes in the developing rat thymus. BIOCHEMISTRY (MOSCOW) 2008; 73:451-7. [DOI: 10.1134/s000629790804010x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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21
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Nerve growth factor stimulates proliferation, adhesion and thymopoietic cytokine expression in mouse thymic epithelial cells in vitro. ACTA ACUST UNITED AC 2008; 147:72-81. [PMID: 18276023 DOI: 10.1016/j.regpep.2008.01.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2007] [Revised: 11/24/2007] [Accepted: 01/02/2008] [Indexed: 11/23/2022]
Abstract
Thymic epithelial cells, which constitute a major component of the thymic microenvironment, provide a crucial signal for intrathymic T cell development and selection. Neuroimmune networks in the thymic microenvironment are thought to be involved in the regulation of T cell development. NGF is increasingly recognized as a potent immunomodulator, promoting "cross-talk" between various types of immune system cells. The present study clearly shows that NGF stimulates mouse thymic epithelial cell activities in vitro including cell proliferation, thymocyte adhesion to thymic epithelial cells, and the expression of cell adhesion molecules such as ICAM-1 and VCAM-1, and thymopoietic factors including IL-7, GM-CSF, SDF-1, TARC and TECK. Thus, our data are of considerable clinical importance showing that trophic NGF activity could be used to enhance the thymus regeneration and develop methods to improve host immunity when the immune function is depressed due to thymic involution.
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Pirofski LA, Casadevall A. The damage-response framework of microbial pathogenesis and infectious diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 635:135-46. [PMID: 18841709 PMCID: PMC7123708 DOI: 10.1007/978-0-387-09550-9_11] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Historical and most currently held views of microbial pathogenesis and virulence are plagued by confusing and imprecise terminology and definitions that require revision and exceptions to accommodate new basic science and clinical information about microbes and infectious diseases. These views are also inherently unable to account for the ability of some microbes to cause disease in certain, but not other hosts, because they are grounded in singular, either microbe-or host-centric views. The damage-response framework is an integrated theory of microbial pathogenesis that puts forth the view that microbial pathogenesis reflects the outcome of an interaction between a host and a microbe, with each entity contributing to the nature of the outcome, which in turn depends on the amount of host damage that results from the host-microbe interaction. This view is able to accommodate new information and explain why infection with the same microbe can have different outcomes in different hosts. This chapter describes the origins and conceptual underpinnings of and the outcomes of infection put forth in, the damage-response framework.
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Affiliation(s)
- Liise-anne Pirofski
- Department of Medicine, Division of Infectious Diseases, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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Abstract
Non-human primates (NHP) have become an indispensable model in studying the common and dangerous human chronic infections, including HIV/SIV, Hepatitis C virus, and tuberculosis. More recently, we and others have used aged NHP to model human immune aging. Chronic infections and aging are both characterized by a significant depletion of defined lymphocyte subsets and the compensatory attempts to regenerate the immune system. As the efficacious antiviral drugs and novel methods to improve and boost the immune system emerge, therapeutic immune regeneration has become a realistic goal in both the physiologic and pathologic settings. This article will summarize our current knowledge on this topic and will discuss future research directions as well as the potential and power of translational studies in non-human primate models of infection, aging and bone marrow transplantation.
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Affiliation(s)
- Janko Nikolich-Zugich
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health & Science University, West Campus, 505 NW 185th Avenue, Beaverton, OR 97006, USA.
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Gui J, Zhu X, Dohkan J, Cheng L, Barnes PF, Su DM. The aged thymus shows normal recruitment of lymphohematopoietic progenitors but has defects in thymic epithelial cells. Int Immunol 2007; 19:1201-11. [PMID: 17804689 DOI: 10.1093/intimm/dxm095] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Aging is associated with reduced numbers of all thymocyte sub-populations, including early T-cell progenitors. However, it is unclear if this is due to inadequate recruitment of lymphohematopoietic progenitor cells (LPCs) to the aged thymus or to abnormal development of T cells within the thymus. We found that LPCs from young mice were recruited equally well to the thymi of young or aged mice and that thymic stromal cells (TSCs) from young and old mice expressed similar levels of P-selectin and CCL25, which are believed to mediate recruitment of LPCs to the adult thymus. However, the number of recruited thymocytes in old thymus was markedly reduced after two weeks, indicating that T-cell development or proliferation is defective in the aged thymus. We also found that LPCs from aged and young mice have similar capacities to seed a fetal thymus that was transplanted under the kidney capsule. Thymic epithelial cells (TECs) in aged mice had lower proliferative capacity and higher rate of apoptosis, compared with findings in young animals. In addition, immunofluorescence staining with antibodies to cortical and medullary TECs revealed that aged thymi had a disorganized thymic stromal architecture, combined with reduced cellularity of the medulla, and apoptosis of thymocyte sub-populations in the medullary microenvironment was increased, compared with that in young mice. We conclude that aging does not impair recruitment of LPCs to the thymus, but is characterized by abnormalities in thymic epithelial architecture, especially medullary TEC function that may provide sub-optimal support for thymic development of LPCs.
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Affiliation(s)
- Jingang Gui
- Department of Biomedical Research, University of Texas Health Center at Tyler, Tyler, TX 75708, USA
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25
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Nakagawa R, Mason SM, Michie AM. Determining the role of specific signaling molecules during lymphocyte development in vivo: instant transgenesis. Nat Protoc 2007; 1:1185-93. [PMID: 17406401 DOI: 10.1038/nprot.2006.178] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A common method of determining the role of specific signaling molecules during lymphocyte development is to generate a transgenic mouse. This procedure, while informative, is time consuming, expensive and ultimately does not guarantee a defined answer. Here we present a protocol in which the in vivo effects of a gene of interest on both B and T lymphocyte development may be determined simultaneously in a relatively short time period. This is achieved by introducing a defined gene, such as a wild-type or mutated signaling molecule, into a lymphoid progenitor population by retroviral infection. The retrovirus generates a bicistronic message encoding the gene of interest and GFP, thus enabling identification of retrovirally transduced cells in subsequent lymphocyte lineages. The cells are then introduced into mice deficient for recombinase activating gene 1 (Rag-/- mice), thus allowing the development of donor-derived B and T lymphocytes in vivo. Using this technique, results can be obtained within 3-8 weeks.
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Affiliation(s)
- Rinako Nakagawa
- Division of Cancer Sciences and Molecular Pathology, Section of Experimental Haematology, Royal Infirmary, 10 Alexandra Parade, University of Glasgow, Scotland G31 2ER, UK
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Taqvi S, Dixit L, Roy K. Biomaterial-based notch signaling for the differentiation of hematopoietic stem cells into T cells. J Biomed Mater Res A 2007; 79:689-97. [PMID: 16845670 DOI: 10.1002/jbm.a.30916] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Thymocyte development takes place in a complex milieu of supportive cells and ECM that are responsible for the proliferation, adhesion, migration, and selection processes these cells undergo before reaching maturity. In recent years, the role of notch signaling in lymphocyte development, specifically T-cell development, has been extensively characterized. Although notch ligand mediated signals have been shown to be a necessary component of T-cell generation from stem cells, high-throughput, synthetic biomaterial-based systems for notch-directed stem-cell differentiation into lymphocytes are yet to be reported. Here, we present a microbead-based, artificial notch signaling system to study stem-cell differentiation into the T-cell lineage. Magnetic microbeads were functionalized with the notch ligand DLL4 using streptavidin-biotin binding and antibody-antigen coupling. Immunohistochemistry and flow cytometry analysis indicated approximately 65% conjugation efficiency. Efficient notch signaling through these functionalized microbeads was demonstrated through a myotube inhibition assay in C2C12 myoblasts. Thy1.2(+) early T cells were successfully generated from mouse bone marrow hematopoietic stem cells (BMHSCs) using DLL4 functionalized beads using both insert-based and mixed stromal cell (OP9) coculture conditions, indicating that stem cell-stromal cell physical contact is not necessary for DLL4 directed T-cell differentiation. Coculture studies with bead-to-cell ratios of 1:1 generated higher T-cell differentiation efficiencies, compared to bead-to-cell ratios of 5:1. These data demonstrate the promising potential of this biomaterial-based notch signaling system to generate T cells from stem cells and to elucidate the molecular interactions in T-cell development.
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Affiliation(s)
- Sabia Taqvi
- Department of Biomedical Engineering, University of Texas, Austin, Texas 78712, USA
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Abstract
The thymus provides the essential microenvironment for T-cell development and maturation. Thymic epithelial cells (TECs), which are composed of thymic cortical epithelial cells (cTECs) and thymic medullary epithelial cells (mTECs), have been well documented to be critical for these tightly regulated processes. It has long been controversial whether the common progenitor cells of TECs could give rise to both cTECs and mTECs. Great progress has been made to characterize the common TEC progenitor cells in recent years. We herein discuss the sole origin paradigm with regard to TEC differentiation as well as these progenitor cells in thymus regeneration.
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Affiliation(s)
- Lianjun Zhang
- Transplantation Biology Research Division, State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080, China
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28
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You JH, Song HK, Jeong DC, Bae DH. Normal Lymphocyte Subpopulation of the Spleen is Altered after Peripheral Nerve Injury in Mice. Korean J Anesthesiol 2007. [DOI: 10.4097/kjae.2007.53.6.s42] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Joo Hyun You
- Department of Anesthesioloy and Pain Medicine, Our Lady of Mercy Hospital, The Catholic University College of Medicine, Incheon, Korea
| | - Ho-Kyung Song
- Department of Anesthesioloy and Pain Medicine, Our Lady of Mercy Hospital, The Catholic University College of Medicine, Incheon, Korea
| | - Dae Chul Jeong
- Department of Pediatrics, Our Lady of Mercy Hospital, The Catholic University College of Medicine, Incheon, Korea
| | - Da Hyoun Bae
- Department of Anesthesioloy and Pain Medicine, Our Lady of Mercy Hospital, The Catholic University College of Medicine, Incheon, Korea
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29
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Kang YJ, Song HK, Chon JY, You JH. Alterations in NK Cell Cytotoxicity Induced by Peripheral Nerve Injury in Mice. Korean J Anesthesiol 2007. [DOI: 10.4097/kjae.2007.52.2.219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- You Jin Kang
- Department of Anesthesiology and Pain Medicine, St. Vincent's Hospital, Suwon, Korea
| | - Ho-Kyung Song
- Department of Anesthesiology and Pain Medicine, Our Lady of Mercy Hospital, Incheon, Korea
| | - Jin Young Chon
- Department of Anesthesiology and Pain Medicine, St. Mary's Hospital, The Catholic University of Korea College of Medicine, Seoul, Korea
| | - Joo Hyun You
- Department of Anesthesiology and Pain Medicine, Our Lady of Mercy Hospital, Incheon, Korea
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31
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Muñoz JJ, Alfaro D, García-Ceca J, Alonso-C LM, Jiménez E, Zapata A. Thymic Alterations in EphA4-Deficient Mice. THE JOURNAL OF IMMUNOLOGY 2006; 177:804-13. [DOI: 10.4049/jimmunol.177.2.804] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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32
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Goldschneider I. Cyclical mobilization and gated importation of thymocyte progenitors in the adult mouse: evidence for a thymus-bone marrow feedback loop. Immunol Rev 2006; 209:58-75. [PMID: 16448534 DOI: 10.1111/j.0105-2896.2006.00354.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
It has recently been observed, as in the fetal thymus, that the importation of hematogenous thymocyte progenitors by the adult thymus is a gated phenomenon, whereby saturating numbers of progenitors periodically enter the thymus and occupy a finite number of intrathymic niches. In addition, the mobilization of thymocyte progenitors from the bone marrow appears to be a cyclical process that coincides temporally with the periods of thymic receptivity (open gate). It is proposed that these events are coordinated by a thymus-bone marrow feedback loop in which a wave of developing triple negative (CD3- CD4- CD8-) thymocytes interacts with stromal cells in the stratified regions of the thymus cortex to sequentially induce the release of diffusible cytokines that regulate the production, mobilization, and recruitment of thymocyte progenitors. The likely components of this feedback loop are described here, as are the properties of the intrathymic vascular gates and niches for thymocyte progenitors. The cyclical production and release of thymocyte progenitors from the bone marrow is placed in the context of a general phenomenon of oscillatory feedback regulation involving all lymphohemopoietic cell lineages. Lastly, the question of whether the gated (as opposed to the continuous) entry of thymocyte progenitors is essential for normal thymocytopoiesis in adult life is discussed.
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Affiliation(s)
- Irving Goldschneider
- Department of Immunology, University of Connecticut Health Center, Farmington, CT 06030, USA.
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33
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Arudchelvan Y, Tokuda N, Adachi Y, Sawada T, Fukumoto T. Ultrastructural alterations of the cortical epithelial cells of the irradiated and recovering rat thymus. ACTA ACUST UNITED AC 2006; 68:205-12. [PMID: 16276026 DOI: 10.1679/aohc.68.205] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
To understand the roles of cortical thymic epithelial cells (CTECs) in T-lymphocyte development, we analyzed rat thymi recovering from irradiation (6Gy), at the ultrastructural level. The morphological alterations in the CTECs were most prominent during the third to fifth day of recovery, when proliferating thymocytes were observed in the vicinity of the CTECs. The most striking finding among the alterations in the CTECs after irradiation was a cytoplasmic vacuolization with an increased amount of granular and membranous content. The granular content was observed as loosely aggregated structures or finely dispersed granules and dense bodies. The membranous content appeared in various forms including vesicular, tubular, and irregular membranous structures and myelin figures. The above features are characteristic of the hyperfunctional state of CTECs with increased secretion activities, which suggests their important roles in the repopulation and maturation of the cortical thymocytes during recovery after irradiation.
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Affiliation(s)
- Yamini Arudchelvan
- Department of Human Science, Yamaguchi University School of Medicine, Ube, Japan.
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Shibakusa T, Iwaki Y, Mizunoya W, Matsumura S, Nishizawa Y, Inoue K, Fushiki T. The physiological and behavioral effects of subchronic intracisternal administration of TGF-β in rats: comparison with the effects of CRF. Biomed Res 2006; 27:297-305. [PMID: 17213686 DOI: 10.2220/biomedres.27.297] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We studied the physiological and behavioral effects of subchronic intracisternal administration of transforming growth factor-beta (TGF-beta) for 7 days. Subchronic intracisternal administration of TGF-beta significantly inhibited the increase in body weight of rats but did not affect food intake. In the measurement of locomotor activity after the final intracisternal administration on day 7, the total count for 1.5 h increased significantly in the TGF-beta group compared with the vehicle group. However, that for 10 h was not different between both groups. Furthermore, significant elevations in oxygen consumption were observed in the TGF-beta group during both light and dark phase. Subchronic TGF-beta treatment induced a significant decrease in the number of total leukocytes and lymphocytes and the relative weight of the thymus, and a significant increase in brown adipose tissue weight. Corticotropin-releasing factor (CRF) is the primary neuroendocrine factor released in response to stress. Subchronic treatment with CRF, as a positive control, significantly affected body weight, food intake, oxygen consumption, total leukocyte and lymphocyte counts, and thymus and adrenal weight. Subchronic TGF-beta administration partially mimicked the stress responses, implicating a role for TGF-beta in the brain in stress.
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Affiliation(s)
- Tetsuro Shibakusa
- Laboratory of Nutrition Chemistry, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Japan
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35
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Clark RA, Yamanaka KI, Bai M, Dowgiert R, Kupper TS. Human skin cells support thymus-independent T cell development. J Clin Invest 2005; 115:3239-49. [PMID: 16224538 PMCID: PMC1253623 DOI: 10.1172/jci24731] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2005] [Accepted: 08/09/2005] [Indexed: 12/22/2022] Open
Abstract
Thymic tissue has previously been considered a requirement for the generation of a functional and diverse population of human T cells. We report that fibroblasts and keratinocytes from human skin arrayed on a synthetic 3-dimensional matrix support the development of functional human T cells from hematopoietic precursor cells in the absence of thymic tissue. Newly generated T cells contained T cell receptor excision circles, possessed a diverse T cell repertoire, and were functionally mature and tolerant to self MHC, indicating successful completion of positive and negative selection. Skin cell cultures expressed the AIRE, Foxn1, and Hoxa3 transcription factors and a panel of autoantigens. Skin and bone marrow biopsies can thus be used to generate de novo functional and diverse T cell populations for potential therapeutic use in immunosuppressed patients.
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Affiliation(s)
- Rachael A Clark
- Harvard Skin Disease Research Center and Department of Dermatology, Brigham and Women's Hospital, Harvard Institutes of Medicine, Boston, Massachusetts 02115, USA
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36
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Bhatt R, Bhatt S, Hameed M, Rameshwar P, Siegel A. Amygdaloid kindled seizures can induce functional and pathological changes in thymus of rat: role of the sympathetic nervous system. Neurobiol Dis 2005; 21:127-37. [PMID: 16084731 DOI: 10.1016/j.nbd.2005.06.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2005] [Revised: 06/03/2005] [Accepted: 06/15/2005] [Indexed: 12/15/2022] Open
Abstract
The present study sought to determine the effects of long-term kindled seizures of the basal amygdala upon immune function in rat, utilizing the thymus, as a principal target for study. Histopathology from kindled Sprague-Dawley rats revealed the presence of epithelial cell thymoma in 70% of these rats. The results revealed an increased rate of apoptosis and proliferation in thymic epithelial cells. Analysis of thymocytes indicated a decrease in the ratio of CD4 to CD8 positive T cells and reduced proliferative response to T-cell mitogens. To determine whether these effects were mediated through the sympathetic nervous system, animals were treated with guanethidine, which blocked the development of epithelial cell thymomas, while mifepristone treatment, employed to determine the possible role of the hypothalamic-pituitary axis, was ineffective in attenuating thymoma development. Thus, the present study demonstrated that functional and pathological changes in the thymus during kindled seizures are mediated through the sympathetic nervous system.
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Affiliation(s)
- Rekha Bhatt
- Department of Neurology and Neurosciences, University of Medicine and Dentistry of New Jersey, Newark, NJ 07103, USA
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37
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Kohu K, Sato T, Ohno SI, Hayashi K, Uchino R, Abe N, Nakazato M, Yoshida N, Kikuchi T, Iwakura Y, Inoue Y, Watanabe T, Habu S, Satake M. Overexpression of the Runx3 Transcription Factor Increases the Proportion of Mature Thymocytes of the CD8 Single-Positive Lineage. THE JOURNAL OF IMMUNOLOGY 2005; 174:2627-36. [PMID: 15728469 DOI: 10.4049/jimmunol.174.5.2627] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The Runx family of transcription factors is thought to regulate the differentiation of thymocytes. Runx3 protein is detected mainly in the CD4(-)8(+) subset of T lymphocytes. In the thymus of Runx3-deficient mice, CD4 expression is de-repressed and CD4(-)8(+) thymocytes do not develop. This clearly implicates Runx3 in CD4 silencing, but does not necessarily prove its role in the differentiation of CD4(-)8(+) thymocytes per se. In the present study, we created transgenic mice that overexpress Runx3 and analyzed the development of thymocytes in these animals. In the Runx3-transgenic thymus, the number of CD4(-)8(+) cells was greatly increased, whereas the numbers of CD4(+)8(+) and CD4(+)8(-) cells were reduced. The CD4(-)8(+) transgenic thymocytes contained mature cells with a TCR(high)HSA(low) phenotype. These cells were released from the thymus and contributed to the elevated level of CD4(-)8(+) cells relative to CD4(+)8(-) cells in the spleen. Runx3 overexpression also increased the number of mature CD4(-)8(+) thymocytes in mice with class II-restricted, transgenic TCR and in mice with a class I-deficient background, both of which are favorable for CD4(+)8(-) lineage selection. Thus, Runx3 can drive thymocytes to select the CD4(-)8(+) lineage. This activity is likely to be due to more than a simple silencing of CD4 gene expression.
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Affiliation(s)
- Kazuyoshi Kohu
- Department of Molecular Immunology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
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38
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Inspiration for the Next Generation of Artificial Immune Systems. LECTURE NOTES IN COMPUTER SCIENCE 2005. [DOI: 10.1007/11536444_10] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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39
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de Saint Basile G, Geissmann F, Flori E, Uring-Lambert B, Soudais C, Cavazzana-Calvo M, Durandy A, Jabado N, Fischer A, Le Deist F. Severe combined immunodeficiency caused by deficiency in either the delta or the epsilon subunit of CD3. J Clin Invest 2004; 114:1512-7. [PMID: 15546002 PMCID: PMC525745 DOI: 10.1172/jci22588] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2004] [Accepted: 08/24/2004] [Indexed: 02/02/2023] Open
Abstract
We investigated the molecular mechanism underlying a severe combined immunodeficiency characterized by the selective and complete absence of T cells. The condition was found in 5 patients and 2 fetuses from 3 consanguineous families. Linkage analysis performed on the 3 families revealed that the patients were carrying homozygous haplotypes within the 11q23 region, in which the genes encoding the gamma, delta, and epsilon subunits of CD3 are located. Patients and affected fetuses from 2 families were homozygous for a mutation in the CD3D gene, and patients from the third family were homozygous for a mutation in the CD3E gene. The thymus from a CD3delta-deficient fetus was analyzed and revealed that T cell differentiation was blocked at entry into the double positive (CD4+CD8+) stage with the accumulation of intermediate CD4-single positive cells. This indicates that CD3delta plays an essential role in promoting progression of early thymocytes toward double-positive stage. Altogether, these findings extend the known molecular mechanisms underlying severe combined immunodeficiency to a new deficiency, i.e., CD3epsilon deficiency, and emphasize the essential roles played by the CD3epsilon and CD3delta subunits in human thymocyte development, since these subunits associate with both the pre-TCR and the TCR.
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40
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Basile GDS, Geissmann F, Flori E, Uring-Lambert B, Soudais C, Cavazzana-Calvo M, Durandy A, Jabado N, Fischer A, Deist FL. Severe combined immunodeficiency caused by deficiency in either the δ or the ε subunit of CD3. J Clin Invest 2004. [DOI: 10.1172/jci200422588] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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41
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Shah N, Asch RJ, Lysholm AS, Lebien TW. Enhancement of stress-induced apoptosis in B-lineage cells by caspase-9 inhibitor. Blood 2004; 104:2873-8. [PMID: 15242874 DOI: 10.1182/blood-2003-10-3720] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
We have established human B-lineage (BLIN) acute lymphoblastic leukemia cell lines that retain a dependency on fibroblast monolayers for survival and proliferation. Eight hours following removal from adherent cell contact BLIN cells undergo a decrease in mitochondrial transmembrane potential and an increase in annexin V binding. Unexpectedly, the caspase-9 inhibitor (C9i) benzyloxycarbonyl-Leu-Glu-His-Asp-fluoromethylketone enhanced the appearance of apoptotic cells within 8 hours following removal of BLIN cells from fibroblast monolayers. C9i enhancement of apoptosis was dose dependent and did not occur with irreversible inhibitors of caspases-2, -3, -6, and -8. C9i also enhanced apoptosis in cord blood-derived CD19+ B-lineage cells (but not myeloid cells) removed from murine stromal cells. Longer exposure (> 18 hours) to C9i culminated in apoptosis in a panel of B-lineage acute lymphoblastic leukemia (ALL) cell lines in the presence or absence of fibroblast monolayers, as well as in 2 proliferating leukemic cell lines (RAMOS and CEM). BLIN-4L cells made deficient in caspase-9 by RNA interference exhibited no resistance to apoptotic signals and actually showed increased apoptotic sensitivity to staurosporine. These collective results suggest that a 4-amino acid caspase inhibitor of caspase-9 can promote apoptosis and that at least some types of apoptotic pathways in B-lineage ALL do not require caspase-9.
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Affiliation(s)
- Nisha Shah
- Cancer Center and Department of Laboratory Medicine/Pathology, University of Minnesota, Minneapolis, MN 55455, USA
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42
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Prockop SE, Petrie HT. Regulation of Thymus Size by Competition for Stromal Niches among Early T Cell Progenitors. THE JOURNAL OF IMMUNOLOGY 2004; 173:1604-11. [PMID: 15265888 DOI: 10.4049/jimmunol.173.3.1604] [Citation(s) in RCA: 152] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Thymic T cell production is characterized by differentiating waves of non-self-renewing, bone marrow-derived progenitors. The factors constraining new progenitor recruitment, intrathymic precursor expansion, and thymus size remain enigmatic, but are believed to be controlled by a feedback loop responding to lymphoid cellularity and competition for stromal niches. In this study, we show that competition for stromal niches does occur, but is solely limited to cells at the early CD4(-)8(-) precursor stages of differentiation. The overall size of the organ is determined both by this limitation on early precursor expansion, and by a second, cell-intrinsic limit on expansion of progenitor cells transiting to the CD4(+)8(+) stage. Together with asymmetric use of marrow-derived progenitors to reconstitute the intrathymic pool, these processes facilitate continuous generation of new T cells while maintaining a relatively stable organ size.
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Affiliation(s)
- Susan E Prockop
- Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA
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43
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Fonseca PC, Nihei OK, Urban-Maldonado M, Abreu S, de Carvalho ACC, Spray DC, Savino W, Alves LA. Characterization of connexin 30.3 and 43 in thymocytes. Immunol Lett 2004; 94:65-75. [PMID: 15234537 DOI: 10.1016/j.imlet.2004.03.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2004] [Revised: 03/22/2004] [Accepted: 03/23/2004] [Indexed: 02/05/2023]
Abstract
During maturation, thymocytes interact directly and indirectly with different cell types of the thymic microenvironment. Such a cellular communication has been basically ascribed to soluble factors and surface receptors. However, little attention has been given to cellular communication mediated by gap junctions. The existence of these intercellular channels in the immune system remained a controversial issue since the 1970s until recently, when a growing body of evidence has indicated their presence and physiological roles in the immune system. In this work, we investigated whether thymocytes express gap junction-forming proteins (connexins, Cx) and are capable of forming functional intercellular channels. Using RT-PCR, we demonstrated that thymocytes express the mRNA for two Cx isoforms: Cx30.3 and Cx43, but not for Cx26, Cx30, Cx31, Cx31.1, Cx32, Cx33, Cx36, Cx37, Cx40, Cx45, Cx46, and Cx50. In addition, the presence of Cx30.3 and Cx43 was confirmed using different techniques (RNase protection assay, western blot and immunofluorescence). However, despite the expression of these two Cxs, we did not detect functional homocellular coupling between thymocytes or between EL-4 cells (a Cx43 expressing thymic lymphoma-derived cell line) or heterocellular coupling between thymocytes and thymic epithelial cells (TEC) or between EL-4 and TEC in unstimulated conditions. Concluding, in this study, we described for the first time the expression of connexins in thymocytes, which may constitute a new molecule having a functional role in thymocytes maturation.
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Affiliation(s)
- Paula Candida Fonseca
- Laboratório de Pesquisas sobre o Timo, Departamento de Imunologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Brasil, Av. Brasil, 4365 Manguinhos, 21045-900, Rio de Janeiro, RJ, Brazil
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44
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Freitas CS, Dalmau SR, Abdelhay E. Differential expression of notch signaling-related transcripts accompanies Pro-thymocyte proliferation and phenotype transition induced by epidermal growth factor plus insulin in fetal thymus organ cultures. Mem Inst Oswaldo Cruz 2004; 99:381-8. [PMID: 15322627 DOI: 10.1590/s0074-02762004000400007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Thymus regression upon stressing stimuli, such as infectious diseases, is followed by organ reconstitution, paralleling its development in ontogeny. A narrow window of thymus development was here studied, encompassing the pro-T lymphoid precursor expansion during specification stages, by the use of epidermal growth factor plus insulin (INS) in murine fetal thymus organ cultures. Aiming to disclose signaling pathways related to these stages, cultured thymus lobes had their RNA extracted, for the search of transcripts differentially expressed using RNAse protection assays and reverse transcriptase-polymerase chain reactions. We found no difference that could explain INS-driven thymocyte growth, in the pattern of transcripts for death/proliferation mediators, or for a series of growth factor receptors and transcriptional regulators known as essential for thymus development. Thymocyte suspensions from cultured lobes, stained for phenotype analysis by fluorescence activated cell sorting, showed a decreased staining for Notch1 protein at cell surfaces upon INS addition. We analyzed the expression of Notch-related elements, and observed the recruitment of a specific set of transcripts simultaneous and compatible with INS-driven thymocyte growth, namely, transcripts for Notch3, for its ligand Jagged2, and for Deltex1, a mediator of a poorly characterized alternative pathway downstream of the Notch receptor.
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Affiliation(s)
- Claudia Sondermann Freitas
- Laboratório de Biologia Molecular Maury Miranda, Instituto de Biofísica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21949-900, Brazil.
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45
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Affiliation(s)
- C Clare Blackburn
- Institute for Stem Cell Research, The University of Edinburgh, King's Buildings, West Mains Road, Edinburgh EH9 3JQ, UK.
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46
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Hannestad J, Monjil DF, Díaz-Esnal B, Cobo J, Vega JA. Age-dependent changes in the nervous and endocrine control of the thymus. Microsc Res Tech 2004; 63:94-101. [PMID: 14722906 DOI: 10.1002/jemt.20014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The immune system, especially the thymus, undergoes age-related modifications leading to structural and functional changes in the lymphoid organs and immunocompetent cells. Nevertheless, the consequences of thymic involution in the peripheral pool of T-cells are still a matter of controversy. The control of the thymic function is very complex and involves intrathymic signals, the autonomic nervous system, and the endocrine system. Both thymocytes and thymic stromal cells express receptors for a wide range of hormones, as well as for neurotransmitters and neuropeptides, thus affecting thymocytes maturation. This review summarizes the age-dependent variations in the extrathymic components of the thymic microenvironment, i.e., vegetative nerves and hormones, and the possible effects of those changes in the immune function.
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Affiliation(s)
- Jonas Hannestad
- Department of Psychiatry, Duke University, Durham, North Carolina 27710, USA
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47
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Blais ME, Gérard G, Martinic MM, Roy-Proulx G, Zinkernagel RM, Perreault C. Do thymically and strictly extrathymically developing T cells generate similar immune responses? Blood 2003; 103:3102-10. [PMID: 15070691 DOI: 10.1182/blood-2003-09-3311] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
If present in sufficient numbers, could extrathymic T cells substitute for thymus-derived T cells? To address this issue, we studied extrathymic T cells that develop in athymic mice under the influence of oncostatin M (OM). In this model, extensive T-cell development is probably due to amplification of a minor pathway of T-cell differentiation taking place only in the lymph nodes. Extrathymic CD4 T cells expanded poorly and were deficient in providing B-cell help after infection with vesicular stomatitis virus (VSV) and lymphocytic choriomeningitis virus (LCMV). Compared with classic T cells, stimulated extrathymic CD8 T cells produced copious amounts of interferon gamma (IFN-gamma), and their expansion was precocious but of limited amplitude because of a high apoptosis rate. Consequently, although extrathymic cytotoxic T lymphocytes (CTLs) responded to LCMV infection, as evidenced by the expansion of GP33-41 tetramer-positive CD8 T cells, they were unable to eradicate the virus. Our data indicate that the site of development impinges on T-cell quality and function and that extrathymic T cells functionally cannot substitute for classical thymic T cells.
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Affiliation(s)
- Marie-Eve Blais
- Guy-Bernier Research Center, Maisonneuve-Rosemont Hospital, Montreal, QC, Canada
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48
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Varas A, Sacedón R, Hernandez-López C, Jiménez E, García-Ceca J, Arias-Díaz J, Zapata AG, Vicente A. Age-dependent changes in thymic macrophages and dendritic cells. Microsc Res Tech 2003; 62:501-7. [PMID: 14635143 DOI: 10.1002/jemt.10411] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Aging is characterized by the decline and deregulation of several physiological systems, especially the immune system. The involution of the thymus gland has been identified as one of the key events that precedes the age-related decline in immune function. Whereas the decrease in thymocyte numbers and in the thymic output during thymus atrophy has been analyzed by various authors, very little information is available about the age-associated modifications in thymic macrophages and dendritic cells. Here we present evidence that these thymic stromal cell components are only slightly affected by age.
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Affiliation(s)
- Alberto Varas
- Department of Cell Biology, Faculty of Medicine, Complutense University, Madrid, Spain.
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49
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Nihei OK, Campos de Carvalho AC, Spray DC, Savino W, Alves LA. A novel form of cellular communication among thymic epithelial cells: intercellular calcium wave propagation. Am J Physiol Cell Physiol 2003; 285:C1304-13. [PMID: 12878492 DOI: 10.1152/ajpcell.00568.2002] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We here describe intercellular calcium waves as a novel form of cellular communication among thymic epithelial cells. We first characterized the mechanical induction of intercellular calcium waves in different thymic epithelial cell preparations: cortical 1-4C18 and medullary 3-10 thymic epithelial cell lines and primary cultures of thymic "nurse" cells. All thymic epithelial preparations responded with intercellular calcium wave propagation after mechanical stimulation. In general, the propagation efficacy of intercellular calcium waves in these cells was high, reaching 80-100% of the cells within a given confocal microscopic field, with a mean velocity of 6-10 microm/s and mean amplitude of 1.4- to 1.7-fold the basal calcium level. As evaluated by heptanol and suramin treatment, our results suggest the participation of both gap junctions and P2 receptors in the propagation of intercellular calcium waves in thymic nurse cells and the more prominent participation of gap junctions in thymic epithelial cell lines. Finally, in cocultures, the transmission of intercellular calcium wave was not observed between the mechanically stimulated thymic epithelial cell and adherent thymocytes, suggesting that intercellular calcium wave propagation is limited to thymic epithelial cells and does not affect the neighboring thymocytes. In conclusion, these data describe for the first time intercellular calcium waves in thymic epithelial cells and the participation of both gap junctions and P2 receptors in their propagation.
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Affiliation(s)
- O K Nihei
- Laboratory on Thymus Research, Department of Immunology, Institute Oswaldo Cruz, The Oswaldo Cruz Foundation, Av. Brasil 4365, Manguinhos 21045-900, Rio de Janeiro, Brazil
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50
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Abstract
The thymus is a complex epithelial organ in which thymocyte development is dependent upon the sequential contribution of morphologically and phenotypically distinct stromal cell compartments. It is these microenvironments that provide the unique combination of cellular interactions, cytokines, and chemokines to induce thymocyte precursors to undergo a differentiation program that leads to the generation of functional T cells. Despite the indispensable role of thymic epithelium in the generation of T cells, the mediators of this process and the differentiation pathway undertaken by the primordial thymic epithelial cells are not well defined. There is a lack of lineage-specific cell-surface-associated markers, which are needed to characterize putative thymic epithelial stem cell populations. This review explores the role of thymic stromal cells in T-cell development and thymic organogenesis, as well as the molecular signals that contribute to the growth and expansion of primordial thymic epithelial cells. It highlights recent advances in these areas, which have allowed for a lineage relationship amongst thymic epithelial cell subsets to be proposed. While many fundamental questions remain to be addressed, collectively these works have broadened our understanding of how the thymic epithelium becomes specialized in the ability to support thymocyte differentiation. They should also facilitate the development of novel, rationally based therapeutic strategies for the regeneration and manipulation of thymic function in the treatment of many clinical conditions in which defective T cells have an important etiological role.
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Affiliation(s)
- Jason Gill
- Department of Pathology and Immunology, Monash University, Faculty of Medicine, Nursing and Health Sciences, Alfred Medical Research and Education Precinct, Prahran, Australia.
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