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Jiang Q, Ma X, Zhu G, Si W, He L, Yang G. Altered T cell development in an animal model of multiple sclerosis. Exp Neurol 2024; 371:114579. [PMID: 37866699 DOI: 10.1016/j.expneurol.2023.114579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 09/29/2023] [Accepted: 10/17/2023] [Indexed: 10/24/2023]
Abstract
Multiple sclerosis (MS) is a chronic autoimmune disease that affects the central nervous system (CNS), leading to demyelination and axonal degeneration. Experimental autoimmune encephalomyelitis (EAE) is an animal model of MS that has significantly improved our understanding of MS. Studies have observed early thymic involution in MS patients, suggesting the potential involvement of the thymus in CNS autoimmunity. However, our knowledge of the thymus's role in autoimmune disorders affecting the CNS remains limited. In this study, we examined the effects of EAE induction on thymopoiesis and observed alterations in T cell development. These changes were characterized by increased apoptosis and decreased proliferation of thymocytes at the EAE peak stage. We also identified a blockade in the transition from CD4-CD8- double-negative thymocytes to CD4+CD8+ double-positive cells, as evidenced by the accumulation of double-negative stage 1 thymocytes at both the EAE onset and peak stages. Furthermore, positive selection was disrupted in the thymus of EAE mice at both stages, leading to an elevated proportion and number of CD4+CD8- and CD4-CD8+ single-positive cells. Meanwhile, we observed an augmented production of regulatory T cells in the thymus of EAE mice. Moreover, peripheral blood analysis of EAE mice at the onset stage showed expanded T cell subsets but not at the peak stage. We also observed altered expression patterns in thymus-derived CD4+CD8- and CD4-CD8+ single-positive cells between MS patients and healthy controls. Our findings demonstrate a modified T cell development in EAE/MS, providing valuable insights into the potential of modulating thymic function as a targeted therapeutic approach to MS/EAE.
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Affiliation(s)
- Qianling Jiang
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong SAR, 999077, China
| | - Xin Ma
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong SAR, 999077, China
| | - Gaochen Zhu
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong SAR, 999077, China
| | - Wen Si
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong SAR, 999077, China
| | - Lingyu He
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong SAR, 999077, China
| | - Guan Yang
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong SAR, 999077, China.
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2
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Yelland T, Garcia E, Samarakoon Y, Ismail S. The Structural and Biochemical Characterization of UNC119B Cargo Binding and Release Mechanisms. Biochemistry 2021; 60:1952-1963. [PMID: 34130453 PMCID: PMC8246649 DOI: 10.1021/acs.biochem.1c00251] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 05/25/2021] [Indexed: 11/29/2022]
Abstract
Two paralogs of the guanine dissociation inhibitor-like solubilizing factors UNC119, UNC119A and UNC119B, are present in the human genome. UNC119 binds to N-myristoylated proteins and masks the hydrophobic lipid from the hydrophilic cytosol, facilitating trafficking between different membranes. Two classes of UNC119 cargo proteins have been classified: low affinity cargoes, released by the Arf-like proteins ARL2 and ARL3, and high affinity cargoes, which are specifically released by ARL3 and trafficked to either the primary cilium or the immunological synapse. The UNC119 homologues have reported differences in functionality, but the structural and biochemical bases for these differences are unknown. Using myristoylated peptide binding and release assays, we show that peptides sharing the previously identified UNC119A high affinity motif show significant variations of binding affinities to UNC119B of up to 427-fold. Furthermore, we solve the first two crystal structures of UNC119B, one in complex with the high affinity cargo peptide of LCK and a second one in complex with the release factor ARL3. Using these novel structures, we identify a stretch of negatively charged amino acids unique to UNC119B that may undergo a conformational change following binding of a release factor which we propose as an additional release mechanism specific to UNC119B.
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Affiliation(s)
- Tamas Yelland
- Beatson
Cancer Research UK Institute, Glasgow G61 1BD, Scotland
| | - Esther Garcia
- Beatson
Cancer Research UK Institute, Glasgow G61 1BD, Scotland
| | | | - Shehab Ismail
- Beatson
Cancer Research UK Institute, Glasgow G61 1BD, Scotland
- Institute
of Cancer Sciences, University of Glasgow, Glasgow G61 1BD, Scotland
- Department
of Chemistry, KU Leuven, Celestijnenlaan 200G, 3001 Heverlee, Belgium
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3
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Pérez AR, de Meis J, Rodriguez-Galan MC, Savino W. The Thymus in Chagas Disease: Molecular Interactions Involved in Abnormal T-Cell Migration and Differentiation. Front Immunol 2020; 11:1838. [PMID: 32983098 PMCID: PMC7492291 DOI: 10.3389/fimmu.2020.01838] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 07/08/2020] [Indexed: 12/24/2022] Open
Abstract
Chagas disease, caused by the protozoan parasite T. cruzi, is a prevalent parasitic disease in Latin America. Presently, it is spreading around the world by human migration, thus representing a new global health issue. Chronically infected individuals reveal a dissimilar disease progression: while nearly 60% remain without apparent disease for life, 30% develop life-threatening pathologies, such as chronic chagasic cardiomyopathy (CCC) or megaviscerae. Inflammation driven by parasite persistence seems to be involved in the pathophysiology of the disease. However, there is also evidence of the occurrence of autoimmune events, mainly caused by molecular mimicry and bystander activation. In experimental models of disease, is well-established that T. cruzi infects the thymus and causes locally profound structural and functional alterations. The hallmark is a massive loss of CD4+CD8+ double positive (DP) thymocytes, mainly triggered by increased levels of glucocorticoids, although other mechanisms seem to act simultaneously. Thymic epithelial cells (TEC) exhibited an increase in extracellular matrix deposition, which are related to thymocyte migratory alterations. Moreover, medullary TEC showed a decreased expression of AIRE and altered expression of microRNAs, which might be linked to a disrupted negative selection of the T-cell repertoire. Also, almost all stages of thymocyte development are altered, including an abnormal output of CD4−CD8− double negative (DN) and DP immature and mature cells, many of them carrying prohibited TCR-Vβ segments. Evidence has shown that DN and DP cells with an activated phenotype can be tracked in the blood of humans with chronic Chagas disease and also in the secondary lymphoid organs and heart of infected mice, raising new questions about the relevance of these populations in the pathogenesis of Chagas disease and their possible link with thymic alterations and an immunoendocrine imbalance. Here, we discuss diverse molecular mechanisms underlying thymic abnormalities occurring during T. cruzi infection and their link with CCC, which may contribute to the design of innovative strategies to control Chagas disease pathology.
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Affiliation(s)
- Ana Rosa Pérez
- Instituto de Inmunología Clínica y Experimental de Rosario, CONICET-Universidad Nacional de Rosario, Rosario, Argentina.,Centro de Investigación y Producción de Reactivos Biológicos, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Juliana de Meis
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.,National Institute of Science and Technology on Neuroimmunomodulation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.,Rio de Janeiro Research Network on Neuroinflammation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | | | - Wilson Savino
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.,National Institute of Science and Technology on Neuroimmunomodulation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.,Rio de Janeiro Research Network on Neuroinflammation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
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Cao Q, Gao X, Lin Y, Yue C, Wang Y, Quan F, Zhang Z, Liu X, Lu Y, Zhan Y, Yang H, Li X, Qin D, Birnbaumer L, Hao K, Yang Y. Thymopentin ameliorates dextran sulfate sodium-induced colitis by triggering the production of IL-22 in both innate and adaptive lymphocytes. Theranostics 2019; 9:7490-7505. [PMID: 31695782 PMCID: PMC6831468 DOI: 10.7150/thno.35015] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 08/25/2019] [Indexed: 12/13/2022] Open
Abstract
Background: Ulcerative colitis (UC) is a chronic inflammatory gastrointestinal disease, notoriously challenging to treat. Previous studies have found a positive correlation between thymic atrophy and colitis severity. It was, therefore, worthwhile to investigate the effect of thymopentin (TP5), a synthetic pentapeptide corresponding to the active domain of the thymopoietin, on colitis. Methods: Dextran sulfate sodium (DSS)-induced colitis mice were treated with TP5 by subcutaneous injection. Body weight, colon length, colon weight, immune organ index, disease activity index (DAI) score, and the peripheral blood profile were examined. The immune cells of the spleen and colon were analyzed by flow cytometry. Histology was performed on isolated colon tissues for cytokine analysis. Bacterial DNA was extracted from mouse colonic feces to assess the intestinal microbiota. Intestinal lamina propria mononuclear cells (LPMCs), HCT116, CT26, and splenocytes were cultured and treated with TP5. Results: TP5 treatment increased the body weight and colon length, decreased the DAI score, and restored colon architecture of colitic mice. TP5 also decreased the infiltration of immune cells and expression levels of pro-inflammatory cytokines such as IL-6. Importantly, the damaged thymus and compromised lymphocytes in peripheral blood were significantly restored by TP5. Also, the production of IL-22, both in innate and adaptive lymphoid cells, was triggered by TP5. Given the critical role of IL-22 in mucosal host defense, we tested the effect of TP5 on mucus barrier and gut microbiota and found that the number of goblet cells and the level of Mucin-2 expression were restored, and the composition of the gut microbiome was normalized after TP5 treatment. The critical role of IL-22 in the protective effect of TP5 on colitis was further confirmed by administering the anti-IL-22 antibody (αIL-22), which completely abolished the effect of TP5. Furthermore, TP5 significantly increased the expression level of retinoic acid receptor-related orphan receptor γ (RORγt), a transcription factor for IL-22. Consistent with this, RORγt inhibitor abrogated the upregulation of IL-22 induced by TP5. Conclusion: TP5 exerts a protective effect on DSS-induced colitis by triggering the production of IL-22 in both innate and adaptive lymphocytes. This study delineates TP5 as an immunomodulator that may be a potential drug for the treatment of UC.
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Affiliation(s)
- Qiuhua Cao
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
- Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
| | - Xinghua Gao
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
- Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
| | - Yanting Lin
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
- Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
| | - Chongxiu Yue
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
- Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
| | - Yue Wang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
- Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
| | - Fei Quan
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
- Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
| | - Zixuan Zhang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
- Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
| | - Xiaoxuan Liu
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
- Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
| | - Yuan Lu
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
- Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
| | - Yanling Zhan
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
- Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
| | - Hongbao Yang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
- Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
| | - Xianjing Li
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
- Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
| | - Di Qin
- School of Sports and Health, Nanjing sport institute, Nanjing, Jiangsu 210001, PR China
| | - Lutz Birnbaumer
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, USA, and Institute of Biomedical Research (BIOMED), Catholic University of Argentina, Buenos Aires C1107AFF, Argentina
| | - Kun Hao
- Key Lab of Drug Metabolism & Pharmacokinetics, China Pharmaceutical University, Nanjing, Jiangsu 210009, PR China
| | - Yong Yang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
- Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China
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Zakariassen HL, Bendtsen KM, Tougaard P, Hansen AK. Reduced early life mucosal integrity decreases thymic cell counts and increases local, but not thymic regulatory, T cell recruitment: Gut mucosal integrity breach and thymic T cells. EUR J INFLAMM 2019. [DOI: 10.1177/2058739218823466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Early life immune gut microbiota contact is critical for regulatory T cell–mediated oral tolerance induction. We induced a mucosal integrity breach with low dextran sulfate sodium dose right after weaning in BALB/c mice along with a standard high dose to study the impact of increased gut microbiota lymphatic tissue contact on the thymus. Both doses increased gut permeability, which caused a short-term generalized thymic involution and regulatory T cell induction in the mesenteric lymph nodes, even in the absence of clinically apparent inflammation in the low-dose group. The thymic regulatory T cells resisted thymic involution. In the low-dose group, we found acutely altered gut mobilization patterns characterized by changed gut-homing marker CD103 expression on mesenteric lymph node CD4+ T cells as well as on mature CD8+ T cells and developing CD4−/CD8− thymocytes. Furthermore, CD218a (IL-18-receptor-a) expression was acutely decreased on both mature CD8+ T cells and regulatory T cells, while increased on the mesenteric lymph node CD8+ T cells, indicating a direct link between the thymus and the mesenteric lymph nodes with CD218a in a functional role in thymic involution. Acute and non-persisting regulatory responses in the mesenteric lymph nodes were induced in the form of a relative regulatory T cell increase. We saw no changes in total thymic regulatory T cells and thus the thymus does not seem to play a major role of in the regulatory immunity induced by increased gut microbiota lymphatic tissue contact around weaning, which in our study primarily was located to the gut.
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Affiliation(s)
- Hannah Louise Zakariassen
- Section of Experimental Animal Models, Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Katja Maria Bendtsen
- Section of Experimental Animal Models, Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Peter Tougaard
- Section of Experimental Animal Models, Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Axel Kornerup Hansen
- Section of Experimental Animal Models, Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
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6
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Loss of Gα i proteins impairs thymocyte development, disrupts T-cell trafficking, and leads to an expanded population of splenic CD4 +PD-1 +CXCR5 +/- T-cells. Sci Rep 2017. [PMID: 28646160 PMCID: PMC5482867 DOI: 10.1038/s41598-017-04537-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Thymocyte and T cell trafficking relies on signals initiated by G-protein coupled receptors. To address the importance of the G-proteins Gαi2 and Gαi3 in thymocyte and T cell function, we developed several mouse models. Gαi2 deficiency in hematopoietic progenitors led to a small thymus, a double negative (DN)1/DN2 thymocyte transition block, and an accumulation of mature single positive (SP) thymocytes. Loss at the double positive (DP) stage of thymocyte development caused an increase in mature cells within the thymus. In both models an abnormal distribution of memory and naïve CD4 T cells occurred, and peripheral CD4 and CD8 T cells had reduced chemoattractant responses. The loss of Gαi3 had no discernable impact, however the lack of both G-proteins commencing at the DP stage caused a severe T cell phenotype. These mice lacked a thymic medullary region, exhibited thymocyte retention, had a peripheral T cell deficiency, and lacked T cell chemoattractant responses. Yet a noteworthy population of CD4+PD-1+CXCR5+/− cells resided in the spleen of these mice likely due to a loss of regulatory T cell function. Our results delineate a role for Gαi2 in early thymocyte development and for Gαi2/3 in multiple aspects of T cell biology.
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7
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RETRACTED ARTICLE: Mouse models of intestinal inflammation and cancer. Arch Toxicol 2016; 90:2109-2130. [DOI: 10.1007/s00204-016-1747-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 06/01/2016] [Indexed: 12/19/2022]
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8
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González FB, Calmon-Hamaty F, Nô Seara Cordeiro S, Fernández Bussy R, Spinelli SV, D'Attilio L, Bottasso O, Savino W, Cotta-de-Almeida V, Villar SR, Pérez AR. Trypanosoma cruzi Experimental Infection Impacts on the Thymic Regulatory T Cell Compartment. PLoS Negl Trop Dis 2016; 10:e0004285. [PMID: 26745276 PMCID: PMC4706328 DOI: 10.1371/journal.pntd.0004285] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 11/16/2015] [Indexed: 11/18/2022] Open
Abstract
The dynamics of regulatory T cells in the course of Trypanosoma cruzi infection is still debated. We previously demonstrated that acute murine T. cruzi infection results in an impaired peripheral CD4+Foxp3+ T cell differentiation due to the acquisition of an abnormal Th1-like phenotype and altered functional features, negatively impacting on the course of infection. Moreover, T. cruzi infection induces an intense thymic atrophy. As known, the thymus is the primary lymphoid organ in which thymic-derived regulatory T cells, known as tTregs, differentiate. Considering the lack of available data about the effect of T. cruzi infection upon tTregs, we examined tTreg dynamics during the course of disease. We confirmed that T. cruzi infection induces a marked loss of tTreg cell number associated to cell precursor exhaustion, partially avoided by glucocorticoid ablation- and IL-2 survival factor depletion. At the same time, tTregs accumulate within the CD4 single-positive compartment, exhibiting an increased Ki-67/Annexin V ratio compared to controls. Moreover, tTregs enhance after the infection the expression of signature markers (CD25, CD62L and GITR) and they also display alterations in the expression of migration-associated molecules (α chains of VLAs and chemokine receptors) such as functional fibronectin-driven migratory disturbance. Taken together, we provide data demonstrating profound alterations in tTreg compartment during acute murine T. cruzi infection, denoting that their homeostasis is significantly affected. The evident loss of tTreg cell number may compromise the composition of tTreg peripheral pool, and such sustained alteration over time may be partially related to the immune dysregulation observed in the chronic phase of the disease.
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Affiliation(s)
- Florencia Belén González
- Institute of Clinical and Experimental Immunology of Rosario (IDICER CONICET-UNR), Rosario, Argentina
| | - Flavia Calmon-Hamaty
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Synara Nô Seara Cordeiro
- Laboratory of Innovations in Therapy, Teaching and Bioproducts, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Rodrigo Fernández Bussy
- Institute of Clinical and Experimental Immunology of Rosario (IDICER CONICET-UNR), Rosario, Argentina
| | - Silvana Virginia Spinelli
- Institute of Clinical and Experimental Immunology of Rosario (IDICER CONICET-UNR), Rosario, Argentina
| | - Luciano D'Attilio
- Institute of Clinical and Experimental Immunology of Rosario (IDICER CONICET-UNR), Rosario, Argentina
| | - Oscar Bottasso
- Institute of Clinical and Experimental Immunology of Rosario (IDICER CONICET-UNR), Rosario, Argentina
| | - Wilson Savino
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Vinícius Cotta-de-Almeida
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Silvina Raquel Villar
- Institute of Clinical and Experimental Immunology of Rosario (IDICER CONICET-UNR), Rosario, Argentina
| | - Ana Rosa Pérez
- Institute of Clinical and Experimental Immunology of Rosario (IDICER CONICET-UNR), Rosario, Argentina
- * E-mail: ,
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9
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Xu X, Ge Q. Maturation and migration of murine CD4 single positive thymocytes and thymic emigrants. Comput Struct Biotechnol J 2014; 9:e201403003. [PMID: 24757506 PMCID: PMC3995209 DOI: 10.5936/csbj.201403003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 03/18/2014] [Accepted: 03/23/2014] [Indexed: 11/22/2022] Open
Abstract
T lymphopoiesis in the thymus was thought to be completed once they reach the single positive (SP) stage, when they are “fully mature” and wait to be exported at random or follow a “first in-first out” manner. Recently, accumulating evidence has revealed that newly generated SP thymocytes undergo further maturation in the thymic medulla before they follow a tightly regulated emigrating process to become recent thymic emigrants (RTEs). RTEs in the periphery then experience a post-thymic maturation and peripheral tolerance and eventually become licensed as mature naïve T cells. This review summarizes the recent progress in the late stage T cell development in and outside of the thymus. The regulation of this developmental process is also discussed.
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Affiliation(s)
- Xi Xu
- Key Laboratory of Medical Immunology, Ministry of Health. Department of Immunology, School of Basic Medical Sciences, Peking University Health Science Center, 38 Xue Yuan Road, Beijing 100191, P R China
| | - Qing Ge
- Key Laboratory of Medical Immunology, Ministry of Health. Department of Immunology, School of Basic Medical Sciences, Peking University Health Science Center, 38 Xue Yuan Road, Beijing 100191, P R China
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10
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Boularan C, Kehrl JH. Implications of non-canonical G-protein signaling for the immune system. Cell Signal 2014; 26:1269-82. [PMID: 24583286 DOI: 10.1016/j.cellsig.2014.02.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 02/22/2014] [Indexed: 01/13/2023]
Abstract
Heterotrimeric guanine nucleotide-binding proteins (G proteins), which consist of three subunits α, β, and γ, function as molecular switches to control downstream effector molecules activated by G protein-coupled receptors (GPCRs). The GTP/GDP binding status of Gα transmits information about the ligand binding state of the GPCR to intended signal transduction pathways. In immune cells heterotrimeric G proteins impact signal transduction pathways that directly, or indirectly, regulate cell migration, activation, survival, proliferation, and differentiation. The cells of the innate and adaptive immune system abundantly express chemoattractant receptors and lesser amounts of many other types of GPCRs. But heterotrimeric G-proteins not only function in classical GPCR signaling, but also in non-canonical signaling. In these pathways the guanine exchange factor (GEF) exerted by a GPCR in the canonical pathway is replaced or supplemented by another protein such as Ric-8A. In addition, other proteins such as AGS3-6 can compete with Gβγ for binding to GDP bound Gα. This competition can promote Gβγ signaling by freeing Gβγ from rapidly rebinding GDP bound Gα. The proteins that participate in these non-canonical signaling pathways will be briefly described and their role, or potential one, in cells of the immune system will be highlighted.
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Affiliation(s)
- Cédric Boularan
- B-cell Molecular Immunology Section, Laboratory of Immunoregulation, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, United States
| | - John H Kehrl
- B-cell Molecular Immunology Section, Laboratory of Immunoregulation, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, United States.
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11
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Wilson GS, George J. Physical and chemical insults induce inflammation and gastrointestinal cancers. Cancer Lett 2013; 345:190-5. [PMID: 23879959 DOI: 10.1016/j.canlet.2013.07.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Revised: 07/02/2013] [Accepted: 07/10/2013] [Indexed: 02/07/2023]
Abstract
Chronic inflammation associated with viral and bacterial infections of the gastrointestinal tract (GI) and liver renders these organs susceptible to tumour development. There is also a growing body of evidence demonstrating that chemical and physical insults promote GI cancers by inducing inflammation. For example, excessive alcohol consumption and tobacco smoking induces inflammation and gastrointestinal carcinogenesis. Likewise, drinking hot beverages and intentional or accidental exposure to toxic substances leads to inflammation and GI cancer formation. However, further work needs to be undertaken using animal models to separate the direct carcinogenic effects of physical and chemical insults from the indirect effects of these insults to promote tumor formation through tissue inflammation.
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Affiliation(s)
- George S Wilson
- Storr Liver Unit, Westmead Millennium Institute, University of Sydney at Westmead Hospital, Westmead, NSW 2145, Australia
| | - Jacob George
- Storr Liver Unit, Westmead Millennium Institute, University of Sydney at Westmead Hospital, Westmead, NSW 2145, Australia.
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12
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Reduced T cell receptor excision circle levels in the colonic mucosa of microscopic colitis patients indicate local proliferation rather than homing of peripheral lymphocytes to the inflamed mucosa. BIOMED RESEARCH INTERNATIONAL 2013; 2013:408638. [PMID: 23956982 PMCID: PMC3727133 DOI: 10.1155/2013/408638] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 06/20/2013] [Accepted: 06/24/2013] [Indexed: 12/15/2022]
Abstract
Dysregulated T cell responses in the intestine may lead to chronic bowel inflammation such as collagenous colitis (CC) and lymphocytic colitis (LC), together known as microscopic colitis (MC). Having demonstrated increased local T cell responses in the intestinal mucosa of MC patients, we investigated the recent thymic emigrants by measuring T cell receptor excision circle (TREC) levels in the colonic biopsies from CC (n = 8), LC (n = 5), and CC or LC patients in histopathological remission (CC-HR, n = 3) (LC-HR, n = 6), non-inflamed diarrhoea patients (n = 17), and controls (n = 10) by real-time PCR. We observed lower median TREC levels in both CC and LC patients as well as in LC-HR patients compared to controls. In contrast to MC patients, non-inflamed diarrhoea patients presented with enhanced TREC levels compared to controls. None of the recorded differences did, however, reach statistical significance. A trend towards increased relative expression of CD3 was noted in all MC subgroups examined and reached statistical significance in LC patients compared to controls. In conclusion, reduced TRECs level in the colonic mucosa, together with our previously demonstrated enhanced expression of Ki67+ T cells, suggests local expansion of resident T lymphocytes in the inflamed mucosa of MC patients.
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Wang Y, Li Y, Shi G. The regulating function of heterotrimeric G proteins in the immune system. Arch Immunol Ther Exp (Warsz) 2013; 61:309-19. [PMID: 23563866 DOI: 10.1007/s00005-013-0230-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Accepted: 03/25/2013] [Indexed: 01/17/2023]
Abstract
Heterotrimeric guanine nucleotide-binding proteins (G proteins), which consist of an α-, a β- and a γ-subunit, have crucial roles as molecular switches in the regulation of the downstream effector molecules of multiple G protein-coupled receptor signalling pathways, such as phospholipase C and adenylyl cyclase. According to the structural and functional similarities of their α-subunits, G proteins can be divided into four subfamilies: Gαs, Gαi/o, Gαq/11 and Gα12/13. Most of the α- and the βγ-subunits are abundantly expressed on the surface of immune cells. Recent studies have demonstrated that G proteins are a group of important immunomodulatory factors that regulate the migration, activation, survival, proliferation, differentiation and cytokine secretion of immune cells. In this review, we summarise the recent findings on the functions of G proteins in immune regulation and autoimmunity.
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Affiliation(s)
- Yantang Wang
- Department of Immunology, Chengdu Medical College, Chengdu, China
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Abstract
Inflammatory bowel disease is characterized by a number of immunological alterations, not the least in the T-cell compartment. Numerous animal models of colitis have revealed aberrant thymocyte dynamics associated with skewed thymocyte development. The recent advancements in quantitative methods have proposed critical kinetic alterations in the thymocyte development during the progression of colitis. This review focuses on the aberrant thymocyte dynamics in Gαi2-deficient mice as this mouse model provides most quantitative data of the thymocyte development associated with colitis. Herein, we discuss several dynamic changes during the progression of colitis and propose a hypothesis for the underlying causes for the skewed proportions of the thymocyte populations seen in the Gαi2-deficient mice and in other mouse models of colitis.
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Götlind YY, Fritsch Fredin M, Kumawat AK, Strid H, Willén R, Rangel I, Bland PW, Hörnquist EH. Interplay between T(h)1 and T(h)17 effector T-cell pathways in the pathogenesis of spontaneous colitis and colon cancer in the Gαi2-deficient mouse. Int Immunol 2013; 25:35-44. [PMID: 22962436 DOI: 10.1093/intimm/dxs089] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Gαi2-deficient mice spontaneously develop colitis. Using xMAP technology and RT-PCR, we investigated cytokine/chemokine profiles during histologically defined phases of disease: (i) no/mild, (ii) moderate, (iii) severe colitis without dysplasia/cancer and (iv) severe colitis with dysplasia/cancer, compared with age-matched wild-type (WT) littermates. Colonic dysplasia was observed in 4/11 mice and cancer in 1/11 mice with severe colitis. The histology correlated with progressive increases in colon weight/cm and spleen weight, and decreased thymus weight, all more advanced in mice with dysplasia/cancer. IL-1β, IL-6, IL-12p40, IL-17, TNF-α, CCL2 and CXCL1 protein levels in colons, but not small intestines increased with colitis progression and were significantly increased in mice with moderate and severe colitis compared with WT mice, irrespective of the absence/presence of dysplasia/cancer. CCL5 did not change during colitis progression. Colonic IL-17 transcription increased 40- to 70-fold in all stages of colitis, whereas IFN-γ mRNA was gradually up-regulated 12- to 55-fold with colitis progression, and further to 62-fold in mice with dysplasia/cancer. IL-27 mRNA increased 4- to 15-fold during the course of colitis, and colonic IL-21 transcription increased 3-fold in mice with severe colitis, both irrespective of the absence/presence of dysplasia/cancer. FoxP3 transcription was significantly enhanced (3.5-fold) in mice with moderate and severe colitis, but not in mice with dysplasia/cancer, compared with WT mice. Constrained correspondence analysis demonstrated an association between increased protein levels of TNF-α, CCL2, IL-1β, IL-6 and CXCL1 and dysplasia/cancer. In conclusion, colonic responses are dominated by a mixed T(h)1/T(h)17 phenotype, with increasing T(h)1 cytokine transcription with progression of colitis in Gαi2(-/-) mice.
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Affiliation(s)
- Yu-Yuan Götlind
- Department of Microbiology and Immunology, Institute of Biomedicine and MIVAC, Sahlgrenska Academy, Göteborg University, Göteborg, Sweden
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Elgbratt K, Jansson A, Hultgren-Hörnquist E. A quantitative study of the mechanisms behind thymic atrophy in Gαi2-deficient mice during colitis development. PLoS One 2012; 7:e36726. [PMID: 22590596 PMCID: PMC3349706 DOI: 10.1371/journal.pone.0036726] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Accepted: 04/05/2012] [Indexed: 12/27/2022] Open
Abstract
Mice deficient for the G protein subunit Gαi2 spontaneously develop colitis, a chronic inflammatory disease associated with dysregulated T cell responses. We and others have previously demonstrated a thymic involution in these mice and an aberrant thymocyte dynamics. The Gαi2(-/-) mice have a dramatically reduced fraction of double positive thymocytes and an increased fraction of single positive (SP) thymocytes. In this study, we quantify a number of critical parameters in order to narrow down the underlying mechanisms that cause the dynamical changes of the thymocyte development in the Gαi2(-/-) mice. Our data suggest that the increased fraction of SP thymocytes results only from a decreased number of DP thymocytes, since the number of SP thymocytes in the Gαi2(-/-) mice is comparable to the control littermates. By measuring the frequency of T cell receptor excision circles (TRECs) in the thymocytes, we demonstrate that the number of cell divisions the Gαi2(-/-) SP thymocytes undergo is comparable to SP thymocytes from control littermates. In addition, our data show that the mature SP CD4(+) and CD8(+) thymocytes divide to the same extent before they egress from the thymus. By estimating the number of peripheral TREC(+) T lymphocytes and their death rate, we could calculate the daily egression of thymocytes. Gαi2(-/-) mice with no/mild and moderate colitis were found to have a slower export rate in comparison to the control littermates. The quantitative measurements in this study suggest a number of dynamical changes in the thymocyte development during the progression of colitis.
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Affiliation(s)
- Kristina Elgbratt
- School of Health and Medical Sciences, Örebro University, Örebro, Sweden
| | - Andreas Jansson
- Systems Biology Research Centre, University of Skövde, Skövde, Sweden
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CD4+FoxP3+ regulatory T cells from Gαi2-/- mice are functionally active in vitro, but do not prevent colitis. PLoS One 2011; 6:e25073. [PMID: 21966415 PMCID: PMC3178583 DOI: 10.1371/journal.pone.0025073] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Accepted: 08/26/2011] [Indexed: 12/18/2022] Open
Abstract
Background Mice deficient in the inhibitory G protein subunit Gαi2 spontaneously develop a T helper 1 dominated colitis. We examined whether a defect in CD4+FoxP3+ regulatory T cells (Treg) underpins the pathogenesis of colitis in the Gαi2−/− (Gαi2-deficient) colitis model. Methodology/Principal Findings Using flow cytometry, we found that thymus and colonic lamina propria, but not spleen and mesenteric lymph nodes, of colitic Gαi2−/− mice contained increased frequencies of Treg, whereas FoxP3 expression intensity was similar in Gαi2−/− compared to Gαi2+/− or Gαi2+/+ wild type (WT) mice. The frequency of CD4+FoxP3+ T cells expressing CD103 was significantly increased in Gαi2−/− compared to WT mice. Treg in colons from WT mice clustered in the T cell areas of colonic lymphoid patches (CLP), with relatively few Treg in the lamina propria, as demonstrated by immunohistochemistry. In Gαi2−/− mice, CLP were not observed but lamina propria Treg were increased in number and frequency within the CD4+ infiltrate, compared to WT mice. Using an in vitro co-culture system and flow cytometric analysis of cell division we could demonstrate that the in vitro suppressive function of WT and Gαi2−/− CD4+FoxP3+ regulatory T cells (WT-Treg and KO-Treg) was indistinguishable, but that T effector cells (CD4+25− T cells) from Gαi2−/− mice were less readily suppressed than WT effectors (WT-Teff) by Treg from either source. However, neither WT nor Gαi2−/− Treg was able to suppress colitis induced by adoptive transfer of Gαi2−/− effector T cells (KO-Teff) to RAG2−/− recipients. The enhanced inflammatory activity of Gαi2−/− effectors was accompanied by increased expression of an effector/memory T cell phenotype and increased cytokine secretion, especially IL-4, IL-6 and IFN-γ. Conclusions There is an increased frequency of Gαi2−/− Treg in the colon, and they demonstrate no endogenous functional defect. However, Gαi2−/− T effector cells are dramatically less susceptible to suppression in vitro, and in vivo, despite increased effective numbers of Treg, they cannot prevent disease.
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Westbrook AM, Wei B, Braun J, Schiestl RH. Intestinal inflammation induces genotoxicity to extraintestinal tissues and cell types in mice. Int J Cancer 2011; 129:1815-25. [PMID: 21520038 DOI: 10.1002/ijc.26146] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Accepted: 04/07/2011] [Indexed: 01/17/2023]
Abstract
Chronic intestinal inflammation leads to increased risk of colorectal and small intestinal cancers and is also associated with extraintestinal manifestations such as lymphomas, other solid cancers and autoimmune disorders. We have previously found that acute and chronic intestinal inflammation causes DNA damage to circulating peripheral leukocytes, manifesting a systemic effect in genetically and chemically induced models of intestinal inflammation. Our study addresses the scope of tissue targets and genotoxic damage induced by inflammation-associated genotoxicity. Using several experimental models of intestinal inflammation, we analyzed various types of DNA damage in leukocyte subpopulations of the blood, spleen, mesenteric and peripheral lymph nodes and in intestinal epithelial cells, hepatocytes and the brain. Genotoxicity in the form of DNA single- and double-stranded breaks accompanied by oxidative base damage was found in leukocyte subpopulations of the blood, diverse lymphoid organs, intestinal epithelial cells and hepatocytes. The brain did not demonstrate significant levels of DNA double-stranded breaks as measured by γ-H2AX immunostaining. CD4(+) and CD8(+) T-cells were most sensitive to DNA damage versus other cell types in the peripheral blood. In vivo measurements and in vitro modeling suggested that genotoxicity was induced by increased levels of systemically circulating proinflammatory cytokines. Moreover, genotoxicity involved increased damage rather than reduced repair, as it is not associated with decreased expression of the DNA double-strand break recognition and repair protein, ataxia telangiectasia mutated. These findings suggest that levels of intestinal inflammation contribute to the remote tissue burden of genotoxicity, with potential effects on nonintestinal diseases and cancer.
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Affiliation(s)
- Aya M Westbrook
- Molecular Toxicology Interdepartmental Program, UCLA School of Public Health, Los Angeles, CA 90095, USA
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Elgbratt K, Kurlberg G, Hahn-Zohric M, Hörnquist EH. Rapid migration of thymic emigrants to the colonic mucosa in ulcerative colitis patients. Clin Exp Immunol 2010; 162:325-36. [PMID: 20840654 DOI: 10.1111/j.1365-2249.2010.04230.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Inflammatory bowel disease (IBD) is associated with imbalances of the local intestinal immune responses, with dysregulated CD4(+) T cells contributing to the chronic inflammation. Having demonstrated altered T cell maturation in the thymus in two different mouse models of colitis, we set out to investigate whether abnormalities in T cell maturation is present in patients with ulcerative colitis (UC) or Crohn's disease (CD). Specimens were obtained from peripheral blood (CD; n = 14, UC; n = 22), colon and small intestinal specimens (CD; n = 6, UC; n = 13). As controls, peripheral blood specimens were obtained from healthy volunteers, patients with adenocarcinomas (n = 18) and colonic specimens from patients with adenocarcinomas (n = 14). Recent thymic emigrants were estimated by analysis of the normalized ratio of T cell receptor excision circles (TRECs) by real-time polymerase chain reaction (PCR). The frequency of naive- and proliferating T lymphocytes and markers of extrathymic T cell maturation in the mucosa was analyzed by flow cytometry and real time-PCR. TREC levels in peripheral blood T lymphocytes were similar between IBD patients and controls. In contrast, UC patients demonstrated significantly increased levels of TRECs both in intraepithelial and lamina propria lymphocytes from the colonic mucosa compared to patients with adenocarcinomas and CD. However, markers for extrathymic T cell maturation in the mucosa were not different between controls and IBD patients. The increased TREC levels in mucosal but not peripheral blood lymphocytes in UC patients in the absence of increased extrathymic maturation in situ in the mucosa together demonstrate that recent thymic emigrants are recruited rapidly to the inflamed mucosa of these patients.
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Affiliation(s)
- K Elgbratt
- Department of Clinical Medicine, Örebro University, Sweden
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Westbrook AM, Szakmary A, Schiestl RH. Mechanisms of intestinal inflammation and development of associated cancers: lessons learned from mouse models. Mutat Res 2010; 705:40-59. [PMID: 20298806 PMCID: PMC2878867 DOI: 10.1016/j.mrrev.2010.03.001] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2009] [Revised: 02/21/2010] [Accepted: 03/08/2010] [Indexed: 12/15/2022]
Abstract
Chronic inflammation is strongly associated with approximately 1/5th of all human cancers. Arising from combinations of factors such as environmental exposures, diet, inherited gene polymorphisms, infections, or from dysfunctions of the immune response, chronic inflammation begins as an attempt of the body to remove injurious stimuli; however, over time, this results in continuous tissue destruction and promotion and maintenance of carcinogenesis. Here we focus on intestinal inflammation and its associated cancers, a group of diseases on the rise and affecting millions of people worldwide. Intestinal inflammation can be widely grouped into inflammatory bowel diseases (ulcerative colitis and Crohn's disease) and celiac disease. Long-standing intestinal inflammation is associated with colorectal cancer and small-bowel adenocarcinoma, as well as extraintestinal manifestations, including lymphomas and autoimmune diseases. This article highlights potential mechanisms of pathogenesis in inflammatory bowel diseases and celiac disease, as well as those involved in the progression to associated cancers, most of which have been identified from studies utilizing mouse models of intestinal inflammation. Mouse models of intestinal inflammation can be widely grouped into chemically induced models; genetic models, which make up the bulk of the studied models; adoptive transfer models; and spontaneous models. Studies in these models have lead to the understanding that persistent antigen exposure in the intestinal lumen, in combination with loss of epithelial barrier function, and dysfunction and dysregulation of the innate and adaptive immune responses lead to chronic intestinal inflammation. Transcriptional changes in this environment leading to cell survival, hyperplasia, promotion of angiogenesis, persistent DNA damage, or insufficient repair of DNA damage due to an excess of proinflammatory mediators are then thought to lead to sustained malignant transformation. With regards to extraintestinal manifestations such as lymphoma, however, more suitable models are required to further investigate the complex and heterogeneous mechanisms that may be at play.
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Affiliation(s)
- Aya M. Westbrook
- Molecular Toxicology Interdepartmental Program, UCLA School of Medicine and School of Public Health, University of California at Los Angeles, Los Angeles, CA 90095
- Department of Pathology and Lab Medicine, UCLA School of Medicine and School of Public Health, University of California at Los Angeles, Los Angeles, CA 90095
| | - Akos Szakmary
- Institute for Cancer Research, Medical University of Vienna, Austria
| | - Robert H. Schiestl
- Molecular Toxicology Interdepartmental Program, UCLA School of Medicine and School of Public Health, University of California at Los Angeles, Los Angeles, CA 90095
- Department of Pathology and Lab Medicine, UCLA School of Medicine and School of Public Health, University of California at Los Angeles, Los Angeles, CA 90095
- Institute for Cancer Research, Medical University of Vienna, Austria
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Chen C, Liu F. Research progress in genetic animal models of inflammatory bowel disease. Shijie Huaren Xiaohua Zazhi 2008; 16:3870-3876. [DOI: 10.11569/wcjd.v16.i34.3870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
In inflammatory bowel disease (IBD), experimental models, especially genetic animal models, are known as important tools for detecting potential therapeutic agents and investigating the mechanisms of pathogenesis. This review is intended to cover recent advances in genetic IBD model applications. The models have been classified into two main categories based on the methods of induction: gene knockout (KO) and transgenic.
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