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Zhou H, Yan J, Zhou K, Ji P, Wei Y, Hua Y. Effects of Huangqi Gancao Decoction on intestinal immunity and microbiota in immunocompromised mice models. Front Pharmacol 2024; 15:1390170. [PMID: 38756377 PMCID: PMC11097664 DOI: 10.3389/fphar.2024.1390170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 04/04/2024] [Indexed: 05/18/2024] Open
Abstract
Background The classical medicinal formula Huangqi Gancao Decoction (HQGCD), originating from the medical book" Yi Lin Gai Cuo". Up to now, the studies focusing on the immunoenhancement effects of HQGCD are few, and the actionpathway is not yet clear. Method In this study, SPF male KM mice were utilized as a model for immunosuppression. Comprehensive observations were made regarding the general behavior and condition of the mice, in addition to monitoring fluctuations in body weight and food intake. The blood routine index was measured, and morphological changes in the ileum and colon tissues were examined. The level of secretory immunoglobulin A (sIgA), superoxide dismutase (SOD), and malondialdehyde (MDA) in ileum and colon tissues were quantified. Additionally, the bone marrow total DNA index was assessed. Flow cytometry analyzed the proportions of CD3⁺, CD4⁺, CD8⁺, and CD4+CD8+ double-positive (DP) T lymphocytes in small intestinal intraepithelial lymphocytes (IELs). Lastly, the composition and diversity of the cecal microbiota were evaluated using 16S rDNA sequencing technology. Results After HQGCD intervention, there were no significant changes in the mice's feed intake and body weight. However, the tissue structures of the ileum and colon showed recovery. In the blood routine index, there was an increase in the total white blood cell count, lymphocyte count, red blood cell count, hematocrit, and hemoglobin content. Additionally, the bone marrow total DNA index was elevated. Level of SOD and sIgA in ileum and colon tissues increased, while the level of MDA decreased. The proportions of CD3⁺ and CD4⁺ T lymphocytes within IELs increased, along with an increase in DP T lymphocytes in IELs (DP IELs), whereas the proportion of CD8⁺ T lymphocytes decreased. The cecal microbiota underwent changes, with an increase in the variety and number of beneficial microbiota. Conclusion HQGCD could restore the intestinal immune function of immunocompromised mice, and had a certain positive effect on cecal microbiota.
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Affiliation(s)
- Hai Zhou
- Tranditional Chinese Veterinary Medicine Laboratory, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, Gansu, China
| | - Jianpeng Yan
- Tranditional Chinese Veterinary Medicine Laboratory, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, Gansu, China
- Lanzhou Animal Disease Control Center, Lanzhou, Gansu, China
| | - Ke Zhou
- Tranditional Chinese Veterinary Medicine Laboratory, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, Gansu, China
| | - Peng Ji
- Tranditional Chinese Veterinary Medicine Laboratory, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, Gansu, China
| | - Yanming Wei
- Tranditional Chinese Veterinary Medicine Laboratory, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, Gansu, China
| | - Yongli Hua
- Tranditional Chinese Veterinary Medicine Laboratory, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, Gansu, China
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Machado A, Pouzolles M, Gailhac S, Fritz V, Craveiro M, López-Sánchez U, Kondo T, Pala F, Bosticardo M, Notarangelo LD, Petit V, Taylor N, Zimmermann VS. Phosphate Transporter Profiles in Murine and Human Thymi Identify Thymocytes at Distinct Stages of Differentiation. Front Immunol 2020; 11:1562. [PMID: 32793218 PMCID: PMC7387685 DOI: 10.3389/fimmu.2020.01562] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 06/15/2020] [Indexed: 12/22/2022] Open
Abstract
Thymocyte differentiation is dependent on the availability and transport of metabolites in the thymus niche. As expression of metabolite transporters is a rate-limiting step in nutrient utilization, cell surface transporter levels generally reflect the cell's metabolic state. The GLUT1 glucose transporter is upregulated on actively dividing thymocytes, identifying thymocytes with an increased metabolism. However, it is not clear whether transporters of essential elements such as phosphate are modulated during thymocyte differentiation. While PiT1 and PiT2 are both phosphate transporters in the SLC20 family, we show here that they exhibit distinct expression profiles on both murine and human thymocytes. PiT2 expression distinguishes thymocytes with high metabolic activity, identifying immature murine double negative (CD4−CD8−) DN3b and DN4 thymocyte blasts as well as immature single positive (ISP) CD8 thymocytes. Notably, the absence of PiT2 expression on RAG2-deficient thymocytes, blocked at the DN3a stage, strongly suggests that high PiT2 expression is restricted to thymocytes having undergone a productive TCRβ rearrangement at the DN3a/DN3b transition. Similarly, in the human thymus, PiT2 was upregulated on early post-β selection CD4+ISP and TCRαβ−CD4hiDP thymocytes co-expressing the CD71 transferrin receptor, a marker of metabolic activity. In marked contrast, expression of the PiT1 phosphate importer was detected on mature CD3+ murine and human thymocytes. Notably, PiT1 expression on CD3+DN thymocytes was identified as a biomarker of an aging thymus, increasing from 8.4 ± 1.5% to 42.4 ± 9.4% by 1 year of age (p < 0.0001). We identified these cells as TCRγδ and, most significantly, NKT, representing 77 ± 9% of PiT1+DN thymocytes by 1 year of age (p < 0.001). Thus, metabolic activity and thymic aging are associated with distinct expression profiles of the PiT1 and PiT2 phosphate transporters.
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Affiliation(s)
- Alice Machado
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health (NIH), Bethesda, MD, United States.,Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | - Marie Pouzolles
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Sarah Gailhac
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | - Vanessa Fritz
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | - Marco Craveiro
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | - Uriel López-Sánchez
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | - Taisuke Kondo
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Francesca Pala
- Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, United States
| | - Marita Bosticardo
- Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, United States
| | - Luigi D Notarangelo
- Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, United States
| | | | - Naomi Taylor
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health (NIH), Bethesda, MD, United States.,Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | - Valérie S Zimmermann
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health (NIH), Bethesda, MD, United States.,Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
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3
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Mao K, Chen W, Mu Y, Ao J, Chen X. Molecular characterization and expression analysis during embryo development of CD4-1 homologue in large yellow croaker Larimichthys crocea. FISH & SHELLFISH IMMUNOLOGY 2017; 64:146-154. [PMID: 28254500 DOI: 10.1016/j.fsi.2017.02.044] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 02/17/2017] [Accepted: 02/25/2017] [Indexed: 06/06/2023]
Abstract
CD4+ helper T (Th) cells are a master component of the adaptive immune response. CD4 is one of the most effective surface markers for identifying Th cells. In the present study, we cloned and characterized a CD4-1 homologue, LycCD4-1, from large yellow croaker Larimichthys crocea. The full-length cDNA of LycCD4-1 is 1695 bp long, encoding a protein of 462 amino acids. The deduced LycCD4-1 protein has a typical domain architecture as found in mammalian CD4 molecules, including a signal peptide, four extracellular immunoglobulin-like (Ig-like) domains, a transmembrane region, and a CXC signaling motif in the cytoplasmic tail. Four N-glycosylation sites and 10 cysteine residues were also found in LycCD4-1, which may be essential for its tertiary structure and succeeding function. Homology comparison showed that LycCD4-1 has 27.9-58.4% identity to other teleost fish CD4-1 molecules, and 16.4-20% identity to those of higher vertebrates. Genomic analysis revealed that the LycCD4-1 gene consisted of nine exons and eight introns and exhibited a similar exon-intron organization to other species CD4 genes except for a different intron length. Phylogenetic analysis showed that LycCD4-1 form a cluster with CD4-1 molecules in other fish species. The LycCD4-1 was constitutively expressed in all tissues tested, with a higher expression in gills and spleen. LycCD4-1 mRNA expression in the spleen and head kidney tissue was increased by poly (I:C) at 48 h, whereas its expression levels were somewhat down-regulated at 6 h and 72 h after bacterial vaccine induction in spleen. Unexpectedly, LycCD4-1 mRNA could be detected in each stage of early embryo development since fertilized eggs, with a higher level before mid-gastrula and the highest level in high blastocysts. These results will be helpful for better understanding molecular characteristics of CD4-1 and tracing origin of CD4-1+ cell precursors in fish.
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Affiliation(s)
- Kaiqiong Mao
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, PR China; School of Life Sciences, Xiamen University, Xiamen 361005, PR China
| | - Wei Chen
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, PR China; School of Life Sciences, Xiamen University, Xiamen 361005, PR China
| | - Yinnan Mu
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, PR China
| | - Jingqun Ao
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, PR China
| | - Xinhua Chen
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, PR China; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen 361005, PR China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, PR China.
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Abstract
The discovery and the first studies on thymic hormones (TH) are historically linked with their role on the developmental events of T lymphocytes that occur within the thymus. However, paradoxically, during the most recent years, much more information about the effects of TH on mature effector cells, in relation with those indicating their real functions during the T-cell differentation, have been, in fact, available. Here we report an update discussion concerning the possible role of the cooperation between TH and cytokines in T-cell development. Moreover we illustrate the results obtained by us and other authors, demonstrating a strict connection between the action of thymosins, a family of peptides first isolated and purified from calf thymus (1), and that of cytokines.
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Affiliation(s)
- A. Mastino
- Department of Experimental Medicine and Biochemical Sciences, University of Rome, “Tor Vergata”, 00173 Rome, Italy; Institute of Experimental Medicine, C.N.R., Rome, Italy
| | - C. Favalli
- Department of Experimental Medicine and Biochemical Sciences, University of Rome, “Tor Vergata”, 00173 Rome, Italy; Institute of Experimental Medicine, C.N.R., Rome, Italy
| | - S. Grelli
- Department of Experimental Medicine and Biochemical Sciences, University of Rome, “Tor Vergata”, 00173 Rome, Italy; Institute of Experimental Medicine, C.N.R., Rome, Italy
| | - E. Garaci
- Department of Experimental Medicine and Biochemical Sciences, University of Rome, “Tor Vergata”, 00173 Rome, Italy; Institute of Experimental Medicine, C.N.R., Rome, Italy
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5
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Abstract
Age-related regression of the thymus is associated with a decline in naïve T cell output. This is thought to contribute to the reduction in T cell diversity seen in older individuals and linked with increased susceptibility to infection, autoimmune disease, and cancer. Thymic involution is one of the most dramatic and ubiquitous changes seen in the aging immune system, but the mechanisms which underlying this process are poorly understood. However, a picture is emerging, implicating the involvement of both extrinsic and intrinsic factors. In this review we assess the role of the thymic microenvironment as a potential target that regulates thymic involution, question whether thymocyte development in the aged thymus is functionally impaired, and explore the kinetics of thymic involution.
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Affiliation(s)
- Donald B Palmer
- Infection and Immunity Group, Department of Comparative Biomedical Sciences, Royal Veterinary College, University of London , London , UK
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6
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Thymic nurse cells provide microenvironment for secondary T cell receptor α rearrangement in cortical thymocytes. Proc Natl Acad Sci U S A 2012. [PMID: 23188800 DOI: 10.1073/pnas.1213069109] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Distinct subsets of thymic epithelial cells (TECs) support T-cell development and selection. Isolated TECs contain multicellular complexes that enclose many viable thymocytes. However, the functions of those TECs, termed thymic nurse cells (TNCs), are unclear and the idea that TNCs are present in vivo is questioned. Here, we show that TNCs represent a fraction of cortical (c)TECs that are defined by the expression of thymoproteasomes. Intravital imaging revealed TNCs in the thymic cortex in situ, whereas TNCs were detected neither during embryogenesis nor in the postnatal thymuses of various "positive-selector" T-cell receptor (TCR)-transgenic mice, indicating that TNCs are not essential for T-cell differentiation, including positive selection. Rather, cells within TNCs were enriched for long-lived CD4(+)CD8(+) thymocytes that underwent secondary TCR-Vα rearrangement. Thus, TNC complexes are formed in vivo by persistent cTEC-thymocyte interactions that then provide a microenvironment that optimizes T-cell selection through secondary TCR rearrangement.
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7
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Saba I, Kosan C, Vassen L, Klein-Hitpass L, Möröy T. Miz-1 is required to coordinate the expression of TCRbeta and p53 effector genes at the pre-TCR "beta-selection" checkpoint. THE JOURNAL OF IMMUNOLOGY 2011; 187:2982-92. [PMID: 21841135 DOI: 10.4049/jimmunol.1101451] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Miz-1 is a Broad-complex, Tramtrack and Bric-à-brac/pox virus zinc finger domain (BTB/POZ)-containing protein expressed in lymphoid precursors that can activate or repress transcription. We report in this article that mice expressing a nonfunctional Miz-1 protein lacking the BTB/POZ domain (Miz-1(ΔPOZ)) have a severe differentiation block at the pre-T cell "β-selection" checkpoint, evident by a drastic reduction of CD4(-)CD8(-) double-negative-3 (DN3) and DN4 cell numbers. T cell-specific genes including Rag-1, Rag-2, CD3ε, pTα, and TCRβ are expressed in Miz-1-deficient cells and V(D)J recombination is intact, but few DN3/DN4 cells express a surface pre-TCR. Miz-1-deficient DN3 cells are highly apoptotic and do not divide, which is consistent with enhanced expression of p53 target genes such as Cdkn1a, PUMA, and Noxa. However, neither coexpression of the antiapoptotic protein Bcl2 nor the deletion of p21(CIP1) nor the combination of both relieved Miz-1-deficient DN3/DN4 cells from their differentiation block. Only the coexpression of rearranged TCRαβ and Bcl2 fully rescued Miz-1-deficient DN3/DN4 cell numbers and enabled them to differentiate into DN4TCRβ(+) and double-positive cells. We propose that Miz-1 is a critical factor for the β-selection checkpoint and is required for both the regulation of p53 target genes and proper expression of the pre-TCR to support the proliferative burst of DN3 cells during T cell development.
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Affiliation(s)
- Ingrid Saba
- Institut de Recherches Cliniques de Montréal, Montréal, Québec H2W 1R7, Canada
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8
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Smelty P, Marchal C, Jaffredo T, Sire JY, Fellah JS. [Reappraisal of the role of pTα for pre-TCR signaling: lessons from non mammalian vertebrates]. Med Sci (Paris) 2011; 27:346-8. [PMID: 21524393 DOI: 10.1051/medsci/2011274004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Philippe Smelty
- Université Pierre et Marie Curie, UMR-CNRS 7622, 9, quai Saint-Bernard, 75252 Paris Cedex 05, France
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Painter MW, Davis S, Hardy RR, Mathis D, Benoist C. Transcriptomes of the B and T lineages compared by multiplatform microarray profiling. THE JOURNAL OF IMMUNOLOGY 2011; 186:3047-57. [PMID: 21307297 DOI: 10.4049/jimmunol.1002695] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
T and B lymphocytes are developmentally and functionally related cells of the immune system, representing the two major branches of adaptive immunity. Although originating from a common precursor, they play very different roles: T cells contribute to and drive cell-mediated immunity, whereas B cells secrete Abs. Because of their functional importance and well-characterized differentiation pathways, T and B lymphocytes are ideal cell types with which to understand how functional differences are encoded at the transcriptional level. Although there has been a great deal of interest in defining regulatory factors that distinguish T and B cells, a truly genomewide view of the transcriptional differences between these two cells types has not yet been taken. To obtain a more global perspective of the transcriptional differences underlying T and B cells, we exploited the statistical power of combinatorial profiling on different microarray platforms, and the breadth of the Immunological Genome Project gene expression database, to generate robust differential signatures. We find that differential expression in T and B cells is pervasive, with the majority of transcripts showing statistically significant differences. These distinguishing characteristics are acquired gradually, through all stages of B and T differentiation. In contrast, very few T versus B signature genes are uniquely expressed in these lineages, but are shared throughout immune cells.
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Affiliation(s)
- Michio W Painter
- Department of Pathology, Harvard Medical School, Boston, MA 02215, USA
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Xu SW, Wu JY, Hu KS, Ping HL, Duan ZG, Zhang HF. Molecular cloning and expression of orange-spotted grouper (Epinephelus coioides) CD8α and CD8β genes. FISH & SHELLFISH IMMUNOLOGY 2011; 30:600-608. [PMID: 21193050 DOI: 10.1016/j.fsi.2010.12.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2010] [Revised: 10/24/2010] [Accepted: 12/12/2010] [Indexed: 05/30/2023]
Abstract
T-cell surface glycoprotein CD8 consists of two distinguished chains, termed α and β chains, and functions as a co-receptor for the T-cell receptor by binding to MHC class I proteins. In this study we report the cloning and identification of both CD8α and CD8β genes from orange-spotted grouper (Epinephelus coioides). The predicted grouper CD8α and CD8β proteins were structurally similar to other fish especially to those of Pleuronectiformes. Real-time RT-PCR revealed that the CD8 mRNA was much higher in the thymus than in other immune organs, and the expression level were very low in stomach, liver, and brain. During embryonic development of the grouper, the highest CD8 transcripts were detected in the multi-cell stage, followed by muscle burl stage, which suggested that the multi-cell stage may be critical in CD8 transcript synthesis. Moreover, CD8 mRNA levels were examined in lymphocytes at different time treated with lipopolysaccharide (LPS), polyriboinosinic polyribocytidylic acid (PolyI:C), phytohemagglutinin (PHA), and concanavalin A (ConA). The result showed that the CD8 mRNA levels were significantly affected in time-dependent manner by PolyI:C, PHA, and ConA, but not by LPS.
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Affiliation(s)
- Sheng-wei Xu
- Institute of Aquatic Economic Animals and Guangdong Provincial Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou 510275, PR China
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11
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Ktistaki E, Garefalaki A, Williams A, Andrews SR, Bell DM, Foster KE, Spilianakis CG, Flavell RA, Kosyakova N, Trifonov V, Liehr T, Kioussis D. CD8 locus nuclear dynamics during thymocyte development. THE JOURNAL OF IMMUNOLOGY 2010; 184:5686-95. [PMID: 20404270 DOI: 10.4049/jimmunol.1000170] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Nuclear architecture and chromatin reorganization have recently been shown to orchestrate gene expression and act as key players in developmental pathways. To investigate how regulatory elements in the mouse CD8 gene locus are arranged in space and in relation to each other, three-dimensional fluorescence in situ hybridization and chromosome conformation capture techniques were employed to monitor the repositioning of the locus in relation to its subchromosomal territory and to identify long-range interactions between the different elements during development. Our data demonstrate that CD8 gene expression in murine lymphocytes is accompanied by the relocation of the locus outside its subchromosomal territory. Similar observations in the CD4 locus point to a rather general phenomenon during T cell development. Furthermore, we show that this relocation of the CD8 gene locus is associated with a clustering of regulatory elements forming a tight active chromatin hub in CD8-expressing cells. In contrast, in nonexpressing cells, the gene remains close to the main body of its chromosomal domain and the regulatory elements appear not to interact with each other.
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Affiliation(s)
- Eleni Ktistaki
- Division of Molecular Immunology, Medical Research Council, National Institute for Medical Research, London, United Kingdom
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12
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The effect of age on the phenotype and function of developing thymocytes. J Comp Pathol 2009; 142 Suppl 1:S45-59. [PMID: 20003987 DOI: 10.1016/j.jcpa.2009.10.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Accepted: 10/02/2009] [Indexed: 11/21/2022]
Abstract
The immune system declines with age leading to a progressive deterioration in the ability to respond to infection and vaccination. Age-associated thymic involution is one of the most recognized changes in the ageing immune system and is believed to be a major contributor towards immunosenescence; however, the precise mechanisms involved in age-associated thymic involution remain unclear. In order to gain further insight into the effect of ageing on T-cell development, steady-state thymopoiesis was studied in mice ranging from 1 to 18 months of age. There was a decrease in thymic cellularity with age, but the most dramatic loss occurred early in life. Although there were no alterations in the proportion of the major thymocyte subsets, there was a significant decline in the expression of other key molecules including CD3 and CD24. There was a decline in the ability of thymocytes from older mice to respond to mitogens, which was demonstrated by a failure to up-regulate expression of the activation marker CD69 and to enter the G(2)--M phase of the cell cycle. This was concurrent with an increased resistance to apoptosis in thymocytes from aged animals. Together, these results suggest that T cells may be flawed even before exiting to the periphery and that this could contribute to the age-associated decline in immune function.
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13
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Zamisch M, Tian L, Grenningloh R, Xiong Y, Wildt KF, Ehlers M, Ho IC, Bosselut R. The transcription factor Ets1 is important for CD4 repression and Runx3 up-regulation during CD8 T cell differentiation in the thymus. ACTA ACUST UNITED AC 2009; 206:2685-99. [PMID: 19917777 PMCID: PMC2806616 DOI: 10.1084/jem.20092024] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The transcription factor Ets1 contributes to the differentiation of CD8 lineage cells in the thymus, but how it does so is not understood. In this study, we demonstrate that Ets1 is required for the proper termination of CD4 expression during the differentiation of major histocompatability class 1 (MHC I)–restricted thymocytes, but not for other events associated with their positive selection, including the initiation of cytotoxic gene expression, corticomedullary migration, or thymus exit. We further show that Ets1 promotes expression of Runx3, a transcription factor important for CD8 T cell differentiation and the cessation of Cd4 gene expression. Enforced Runx3 expression in Ets1-deficient MHC I–restricted thymocytes largely rescued their impaired Cd4 silencing, indicating that Ets1 is not required for Runx3 function. Finally, we document that Ets1 binds at least two evolutionarily conserved regions within the Runx3 gene in vivo, supporting the possibility that Ets1 directly contributes to Runx3 transcription. These findings identify Ets1 as a key player during CD8 lineage differentiation and indicate that it acts, at least in part, by promoting Runx3 expression.
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Affiliation(s)
- Monica Zamisch
- Laboratory of Immune Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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14
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Abstract
Translational control is an important but relatively unappreciated mechanism that regulates levels of protein products. In addition to a global translational control that regulates the cell's response to external stimuli such as growth factors, cytokines, stress, and viral infections, selective translational control has recently been demonstrated to affect many genes related to growth and apoptotic processes. Translational infidelity has recently been suggested as a new mechanism of T cell dysregulation in SLE. This review discusses current data on translational control of T cell biology and the central aspect of translational control in the signalling pathway leading to T cell proliferation, apoptotic response, and cytokine production. The utility for global analysis by genomics to study translational control of T cell gene expression is also discussed.
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Affiliation(s)
- Laura Beretta
- Department of Microbiology and Immunology, University of Michigan, Medical School, Ann Arbor, 48109-0620, USA.
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15
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Prabhakar M, Ershler WB, Longo DL. BONE MARROW, THYMUS AND BLOOD: CHANGES ACROSS THE LIFESPAN. AGING HEALTH 2009; 5:385-393. [PMID: 20072723 PMCID: PMC2805199 DOI: 10.2217/ahe.09.31] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The aim of this review is to present age-related changes in the bone marrow and thymus and their effects in later life. Age-related hematologic changes are marked by a decline in marrow cellularity, increased risk of myeloproliferative disorders and anemia, and a decline in adaptive immunity. The exact mechanisms that produce these changes remain undefined. For the most part, the changes in function that are a consequence of aging alone rarely have meaningful clinical consequences. However, in the face of the stresses induced by other illnesses, the decreased physiologic reserve can slow or prevent an appropriate response to the stressors.
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Affiliation(s)
- Mamatha Prabhakar
- Clinical Research Branch, National Institute on Aging, and, Medstar Research Institute, Harbor Hospital, 3001 South Hanover Street, Baltimore, MD 21225, USA
| | - William B Ershler
- Clinical Research Branch, National Institute on Aging, Harbor Hospital, 3001 South Hanover Street, Baltimore, MD 21225, USA
| | - Dan L Longo
- National Institute on Aging, Harbor Hospital, 3001 South Hanover Street, Baltimore, MD 21225, USA
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16
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Aw D, Silva AB, Palmer DB. Is thymocyte development functional in the aged? Aging (Albany NY) 2009; 1:146-53. [PMID: 20157506 PMCID: PMC2806005 DOI: 10.18632/aging.100027] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2009] [Accepted: 02/10/2009] [Indexed: 01/09/2023]
Abstract
T cells are an
integral part of a functional immune system with the majority being produced
in the thymus. Of all the changes related to immunosenescence, regression of the thymus is
considered one of the most universally recognised alterations. Despite the reduction of
thymic size, there is evidence to suggest that T cell output is still
present into old age, albeit much diminished; leading to the assumption
that thymocyte development is normal. However, current data suggests that
recent thymic emigrant from the aged thymus are functionally less
responsive, giving rise to the possibility that the generation of
naïve T cell may be intrinsically impaired in the elderly. In light of
these findings we discuss the evidence that suggest aged T cells may be
flawed even before exiting to the periphery and could contribute to the
age-associated decline in immune function.
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Affiliation(s)
- Danielle Aw
- Infection & Immunity and Genes & Development Group, Department of Veterinary Basic Sciences, Royal Veterinary College, UK
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17
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Balcan E, Gümüş A, Sahin M. The glycosylation status of murine [corrected] postnatal thymus: a study by histochemistry and lectin blotting. J Mol Histol 2008; 39:417-26. [PMID: 18642095 DOI: 10.1007/s10735-008-9180-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Accepted: 07/02/2008] [Indexed: 12/31/2022]
Abstract
During the intrathymic development, the fate of the thymocytes depends largely on variable expression of CD4/CD8 markers and T cell receptor protein expressions. In addition, changes of cell surface glycosylation status also affect the thymocyte maturation. In this study the glycosylation alterations in thymic tissues from 1, 9, 13 and 16 days old mice were evaluated by histochemical and lectin blotting techniques. With alcian blue (AB) at pH 5.7/periodic acid-Schiff (PAS) stainings, it was shown that thymic microenvironments contained carboxlylated and sulfated glycosaminoglycans (GAGs). Strong positivity to AB at pH 2.5, which specific for sialomucins, was seen in some medullary thymocytes. Similarly, it was shown that with Maackia amurensis agglutinin (MAL) medullary thymocytes, but not cortical ones, contained alpha(2 --> 3) linked sialic acid structures. On the other hand, while reaction with peanut agglutinin (PNA), which specific for core disaccharide galactose beta(1 --> 3) N-acetylgalactosamine, was only seen in cortical thymocytes, reaction with Galanthus nivalis agglutinin (GNA), which specific for terminal mannose residues, was seen in both cortex and medulla. However, Datura stramonium agglutinin (DSA), which recognizes galactose beta(1 --> 4) N-acetylglucosamine, was not only cell-specific, but it was bound some thymic vessels. With lectin blotting studies, five glycoprotein bands of molecular weights approximately 39, approximately 54, 100, approximately 110 and approximately 212 were found which reacted with MAL, PNA and DSA as well as GNA. These results suggest that glycosylation patterns of cell surface glycoconjugates are modified during thymocyte selection processes of postnatal days.
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Affiliation(s)
- Erdal Balcan
- Department of Biology, Faculty of Science and Art, Celal Bayar University, Molecular Biology Sect. 45047 Muradiye Campus, Manisa, Turkey.
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18
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Ramsdell F, Zúñiga-Pflücker JC, Takahama Y. In vitro systems for the study of T cell development: fetal thymus organ culture and OP9-DL1 cell coculture. ACTA ACUST UNITED AC 2008; Chapter 3:Unit 3.18. [PMID: 18432973 DOI: 10.1002/0471142735.im0318s71] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Most T cell development occurs within the thymus and includes a series of selection processes that are, in large part, still poorly understood. Studies of T cell development have been greatly advanced by the description of multiple phenotypic subsets of T cells and their maturational relationships. This unit describes a system for observing and modulating T cell development in vitro via the culture of entire mouse fetal thymic lobes. Methods are included for the isolation of fetal thymi and culture to allow for normal T cell development on either transwell plates or Gelfoam sponges. A method for depleting hematopoietic cells from thymic lobes using 2'-deoxyguanosine and subsequent reconstitution with precursor cells is also described. This protocol is valuable for the study of tolerance and T cell selection. A support protocol describing methods of altering and monitoring T cell development are outlined. In addition, methods for culturing fetal thymic lobes under high oxygen submersion conditions and for the preparation of reaggregate thymus organ cultures are provided. Finally, a simple and practical method that allows for the thymus-independent generation of T cells from defined sources of stem/progenitor cells by OP9-DL1 coculture is described.
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19
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Huang F, Naramura M, Gu H. TM1 and TM2: two mutant alleles that are involved in the pre-TCR/TCR signaling. Immunol Cell Biol 2008; 86:475-7. [PMID: 18392045 DOI: 10.1038/icb.2008.11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
It has been shown that the transgene insertional mutations TM1 and TM2 constitute a genetic trait controlling thymocyte development. Here we conducted a detailed analysis of the impact of TM1 and TM2 double mutation on thymocyte development. We found that the hemizygous TM1 and TM2 double transgenic mice possessed much smaller thymi. Flow cytometric analysis revealed a severe blockage of T-cell development at the transition from DN3 to DN4 stage and pre-T-cell receptor (pre-TCR)/TCR signaling appeared to be impaired. We could not identify any known gene that was implicated in a similar function in the chromosomal regions 7E-F1 and 11B5-C, where TM1 and TM2 mutations were mapped to respectively. Thus, TM1 and TM2 mutations represent two novel alleles that define a genetic trait controlling DN3 thymocyte development, possibly through modulating the signals downstream of the pre-TCR.
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Affiliation(s)
- Fang Huang
- Department of Microbiology, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA.
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20
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Balcan E, Tuğlu I, Şahin M, Toparlak P. Cell surface glycosylation diversity of embryonic thymic tissues. Acta Histochem 2007; 110:14-25. [PMID: 18028987 DOI: 10.1016/j.acthis.2007.07.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2007] [Revised: 07/26/2007] [Accepted: 07/31/2007] [Indexed: 01/20/2023]
Abstract
In the thymus, glycosylation status of many cell surface molecules changes during the thymocyte maturation and selection processes. In this study, we evaluated the glycosylation changes and possible relationships with programmed cell death in the thymic tissues from mouse embryos at the days 14 (E14), 15 (E15), 16 (E16), 17 (E17) and 18 (E18) of embryonic development. In order to determine glycosylation changes we used three different plant lectins: peanut agglutinin (PNA), Maackia amurensis leucoagglutinin (MAL or MAAI) and Sambucus nigra agglutinin (SNA), which recognize core disaccharide galactose (1-3) N-acetylgalactosamine [Galbeta(1-->3)GalNAc], sialic acid linked (2-->3) to galactose [SAalpha(2-->3)Gal] and sialic acid linked to galactose [SAalpha(2-->6)Gal] structures, respectively. Our lectin histochemistry and lectin blotting studies indicated that glycosylation pattern was modified in thymocytes at the embryonic developmental stages analyzed. The immature cortical thymocytes were labeled by PNA, whereas medullary thymocytes were positive for MAL and SNA binding. Many medullary thymocytes exhibited alpha(2-->6)-linked sialic acid on their surface and this increased throughout the gestational stages. In the lectin blotting studies, different protein bands of various molecular weights were identified in thymocytes. Two of them were putatively identified as CD43 and CD45 glycoproteins. In addition, TUNEL (deoxynucleotdyltransferase-mediated dUDP nick end labeling) indicated that only PNA-positive cortical thymocytes were deleted in all embryonic stages. These results indicate that the glycosylation pattern was modified in thymocytes at all embryonic developmental stages, and these modifications can affect the T cell deletion, probably via the galectin-1 molecule in the embryonic thymus.
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21
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Huang F, Naramura M, Papaioannou VE, Gu H. TM1 and TM2: two mutant alleles that constitute a genetic trait controlling thymocyte development. Immunogenetics 2007; 59:473-7. [PMID: 17406863 DOI: 10.1007/s00251-007-0207-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2006] [Accepted: 01/28/2007] [Indexed: 12/01/2022]
Abstract
Transgene insertion is instrumental to identifying genes with defined physiological functions. In this paper, we show that mice homozygous for either TM1 or TM2, two mutant alleles with distinct transgene insertions, exhibited embryo lethality, suggesting that these two alleles play essential roles in embryogenesis. Interestingly, although hemizygous TM1 or TM2 alone did not have obvious alteration in thymocyte development, together, they exhibited a compound effect on thymocyte development, blocking the development from CD4 and CD8 double-negative to double-positive stage of T cells. TM1 and TM2 mutations were mapped to chromosome regions 7E-F1 and 11B5-C, respectively, where we could not identify any known gene that was implicated in a similar function. Thus, TM1 and TM2 represent two novel alleles that define a genetic trait controlling thymocyte development.
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Affiliation(s)
- Fang Huang
- Department of Microbiology, Columbia University College of Physicians and Surgeons, HHSC Rm6-611, 701 West 168th street, New York, NY 10032, USA
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22
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Huang F, Kitaura Y, Jang I, Naramura M, Kole HH, Liu L, Qin H, Schlissel MS, Gu H. Establishment of the major compatibility complex-dependent development of CD4+ and CD8+ T cells by the Cbl family proteins. Immunity 2006; 25:571-81. [PMID: 17045823 DOI: 10.1016/j.immuni.2006.08.021] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2004] [Revised: 01/24/2006] [Accepted: 08/01/2006] [Indexed: 10/24/2022]
Abstract
Casitas B cell lymphoma (Cbl) proteins are negative regulators for T cell antigen receptor (TCR) signaling. Their role in thymocyte development remains unclear. Here we show that simultaneous inactivation of c-Cbl and Cbl-b in thymocytes enhanced thymic negative selection and altered the ratio of CD4(+) and CD8(+) T cells. Strikingly, the mutant thymocytes developed into CD4(+)- and CD8(+)-lineage T cells independent of the major histocompatibility complex (MHC), indicating that the CD4(+)- and CD8(+)-lineage development programs are constitutively active in the absence of c-Cbl and Cbl-b. The mutant double-positive (DP) thymocytes exhibited spontaneous hyperactivation of nuclear factor-kappa B (NF-kappaB). Additionally, they failed to downregulate the pre-TCR and pre-TCR signaling. Thus, our data indicate that Cbl proteins play a critical role in establishing the MHC-dependent CD4(+) and CD8(+) T cell development programs. They likely do so by suppressing MHC-independent NF-kappaB activation, possibly through downmodulating pre-TCR signaling in DP thymocytes.
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Affiliation(s)
- Fang Huang
- Department of Microbiology, Columbia University College of Physicians and Surgeons, 701 West 168th Street, New York, New York 10032, USA
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23
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Priceputu E, Bouallaga I, Zhang Y, Li X, Chrobak P, Hanna ZS, Poudrier J, Kay DG, Jolicoeur P. Structurally distinct ligand-binding or ligand-independent Notch1 mutants are leukemogenic but affect thymocyte development, apoptosis, and metastasis differently. THE JOURNAL OF IMMUNOLOGY 2006; 177:2153-66. [PMID: 16887975 DOI: 10.4049/jimmunol.177.4.2153] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We previously found that provirus insertion in T cell tumors of mouse mammary tumor virus/c-myc transgenic (Tg) mice induced two forms of Notch1 mutations. Type I mutations generated two truncated molecules, one intracellular (IC) (Notch1(IC)) and one extracellular (Notch1(EC)), while in type II mutations Notch1 was deleted of its C terminus (Notch1(DeltaCT)). We expressed these mutants in Tg mice using the CD4 promoter. Both Notch1(IC) and Notch1(DeltaCT), but not Notch1(EC), Tg mice developed double-positive (DP) thymomas. These disseminated more frequently in Notch1(DeltaCT) Tg mice. Double (Notch1(IC) x myc) or (Notch1(DeltaCT) x myc) Tg mice developed thymoma with a much shorter latency than single Tg mice, providing genetic evidence of a collaboration between these two oncogenes. FACS analysis of preleukemic thymocytes did not reveal major T cell differentiation anomalies, except for a higher number of DP cells and an accumulation of TCR(high)CD2(high)CD25(high) DP cells in Notch1(IC), and less so in Notch1(DeltaCT) Tg mice. This was associated with enhanced in vivo thymocyte proliferation. However, Notch1(IC), but not Notch1(DeltaCT), DP thymocytes were protected against apoptosis induced in vivo by dexamethasone and anti-CD3 and in vitro by anti-CD3/CD28 Abs. This indicates that the C terminus of Notch1 and/or the conserved regulation by its ligands have a significant impact on the induced T cell phenotype. Therefore, Notch1(IC) and Notch1(DeltaCT) behave as oncogenes for T cells. Because these two Notch1 mutations are very similar to those described in some forms of human T cell leukemia, these Tg mice may represent relevant models of these human leukemias.
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MESH Headings
- Animals
- Apoptosis/genetics
- Apoptosis/immunology
- Cell Differentiation/genetics
- Cell Differentiation/immunology
- Disease Models, Animal
- Gene Deletion
- Leukemia-Lymphoma, Adult T-Cell/genetics
- Leukemia-Lymphoma, Adult T-Cell/immunology
- Leukemia-Lymphoma, Adult T-Cell/pathology
- Ligands
- Lymphatic Metastasis
- Mice
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Mice, Nude
- Mice, Transgenic
- Preleukemia/genetics
- Preleukemia/immunology
- Preleukemia/pathology
- Protein Binding/immunology
- Proto-Oncogene Proteins c-myc/biosynthesis
- Proto-Oncogene Proteins c-myc/genetics
- Receptor, Notch1/biosynthesis
- Receptor, Notch1/chemistry
- Receptor, Notch1/genetics
- Receptor, Notch1/metabolism
- Thymoma/genetics
- Thymoma/immunology
- Thymoma/pathology
- Thymoma/secondary
- Thymus Gland/immunology
- Thymus Gland/pathology
- Thymus Neoplasms/genetics
- Thymus Neoplasms/immunology
- Thymus Neoplasms/pathology
- Thymus Neoplasms/secondary
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Affiliation(s)
- Elena Priceputu
- Laboratory of Molecular Biology, Clinical Research Institute of Montreal, 110 Pine Avenue West, Montréal, Québec, Canada
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24
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Bandera A, Gazzola L, Franzetti F, Tosca N, Sacchi E, Clerici M, Gori A. Unusual T-cell repopulation after autologous stem cell transplantation for HIV-associated lymphoma. Transplantation 2006; 81:1752-3. [PMID: 16794547 DOI: 10.1097/01.tp.0000226081.79388.b6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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25
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Candon S, McHugh RS, Foucras G, Natarajan K, Shevach EM, Margulies DH. Spontaneous organ-specific Th2-mediated autoimmunity in TCR transgenic mice. THE JOURNAL OF IMMUNOLOGY 2004; 172:2917-24. [PMID: 14978094 DOI: 10.4049/jimmunol.172.5.2917] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CD4(+) T cells that lead to autoimmune gastritis (AIG) in BALB/c mice are either Th1 or Th2 cells. To test whether the phenotype of disease is related to the particular TCR expressed by the pathogenic cell, we have generated several lines of TCR transgenic mice using receptors cloned from pathogenic Th1 or Th2 cells. We previously described spontaneous inflammatory AIG in A23 mice, caused by the transgenic expression of the TCR from a Th1 clone, TXA23. In this study we describe the generation of A51 mouse lines, transgenic for the TCR of a CD4(+) self-reactive Th2 clone, TXA51. A proportion of A51 mice spontaneously develop AIG by 10 wk of age, with a disease characterized by eosinophilic infiltration of the gastric mucosa and Th2 differentiation of transgenic T cells in the gastric lymph node. The Th2 phenotype of this autoimmune response seems to be related to a low availability of MHC class II-self peptide complexes. This in vivo model of spontaneous Th2-mediated, organ-specific autoimmunity provides a unique example in which the clonotypic TCR conveys the Th2 disease phenotype.
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Affiliation(s)
- Sophie Candon
- Molecular Biology Section, Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892, USA
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26
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Abstract
Aging involves morphological and functional alterations within the microenvironment of the thymus where heterogenous populations of thymic epithelial cells (TEC) play the main roles. The studies performed to date on thymic involution signalize a disturbed interaction between individual thymic compartments that disrupt thymocyte-TEC interactions and, as a sequele, disturb differentiation of both TEC and thymocytes. The process of aging affects the various subsets of TEC at different periods of life. Changes in different subsets of TEC are documented on the basis of their phenotypical characteristics, involving morphological analysis and immunocytochemistry. The character and kinetics of changes in TEC are typical for individual subsets and probably sex-dependent. In the course of life, the involutionary changes, expressed by disorganised thymic structure and function, are accompanied by changes in medullary TEC, manifested by alterations in the differentiation process of the cells. In parallel, at the same stage of individual life, the aging process induces increased proliferative and secretory activity of subseptal TEC, which seem to functionally replace medullary TEC. Structural and phenotypic modifications of TEC are locally controlled by complex sets of different factors and seem to represent a morphological adaptation of the gland to the process of aging. Microsc. Res. Tech. 62:488-500, 2003.
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Affiliation(s)
- Renata Brelińska
- Department of Histology and Embryology, University of Medical Sciences, Pl-60-781 Poznań, Poland.
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27
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Zhang Z, Cotta CV, Stephan RP, deGuzman CG, Klug CA. Enforced expression of EBF in hematopoietic stem cells restricts lymphopoiesis to the B cell lineage. EMBO J 2003; 22:4759-69. [PMID: 12970188 PMCID: PMC212730 DOI: 10.1093/emboj/cdg464] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Mice deficient in early B cell factor (EBF) are blocked at the progenitor B cell stage prior to immunoglobulin gene rearrangement. The EBF-dependent block in B cell development occurs near the onset of B-lineage commitment, which raises the possibility that EBF may act instructively to specify the B cell fate from uncommitted, multipotential progenitor cells. To test this hypothesis, we transduced enriched hematopoietic progenitor cells with a retroviral vector that coexpressed EBF and the green fluorescent protein (GFP). Mice reconstituted with EBF-expressing cells showed a near complete absence of T lymphocytes. Spleen and peripheral blood samples were >95 and 90% GFP+EBF+ mature B cells, respectively. Both NK and lymphoid-derived dendritic cells were also significantly reduced compared with control-transplanted mice. These data suggest that EBF can restrict lymphopoiesis to the B cell lineage by blocking development of other lymphoid-derived cell pathways.
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Affiliation(s)
- Zheng Zhang
- Department of Microbiology, Division of Developmental and Clinical Immunology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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28
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Rodríguez-Borlado L, Barber DF, Hernández C, Rodríguez-Marcos MA, Sánchez A, Hirsch E, Wymann M, Martínez-A C, Carrera AC. Phosphatidylinositol 3-kinase regulates the CD4/CD8 T cell differentiation ratio. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2003; 170:4475-82. [PMID: 12707323 DOI: 10.4049/jimmunol.170.9.4475] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The signaling pathways that control T cell differentiation have only begun to be elucidated. Using T cell lines, it has been shown that class IA phosphatidylinositol 3-kinase (PI3K), a heterodimer composed of a p85 regulatory and a p110 catalytic subunit, is activated after TCR stimulation. Nonetheless, the contribution of p85/p110 PI3K isoforms in T cell development has not been described. Mice deficient in the other family of class I PI3K, p110gamma, which is regulated by G protein-coupled receptors, exhibit reduced thymus size. Here we examine T cell development in p110gamma-deficient mice and in mice expressing an activating mutation of the p85 regulatory subunit, p65(PI3K), in T cells. We show that p110gamma-deficient mice have a partial defect in pre-TCR-dependent differentiation, which is restored after expression of the p65(PI3K) activating mutation. Genetic alteration of both PI3K isoforms also affects positive selection; p110gamma deletion decreased and p65(PI3K) expression augmented the CD4(+)/CD8(+) differentiation ratio. Finally, data are presented showing that both PI3K isoforms influenced mature thymocyte migration to the periphery. These observations underscore the contribution of PI3K in T cell development, as well as its implication in determining the CD4(+)/CD8(+) T cell differentiation ratio in vivo.
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Affiliation(s)
- Luis Rodríguez-Borlado
- Department of Immunology and Oncology, Centro Nacional de Biotecnología, Universidad Autónoma, Cantoblanco, Madrid, Spain
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29
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Liu X, Adams A, Wildt KF, Aronow B, Feigenbaum L, Bosselut R. Restricting Zap70 expression to CD4+CD8+ thymocytes reveals a T cell receptor-dependent proofreading mechanism controlling the completion of positive selection. J Exp Med 2003; 197:363-73. [PMID: 12566420 PMCID: PMC2193832 DOI: 10.1084/jem.20021698] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Although T cell receptor (TCR) signals are essential for intrathymic T cell-positive selection, it remains controversial whether they only serve to initiate this process, or whether they are required throughout to promote thymocyte differentiation and survival. To address this issue, we have devised a novel approach to interfere with thymocyte TCR signaling in a developmental stage-specific manner in vivo. We have reconstituted mice deficient for Zap70, a tyrosine kinase required for TCR signaling and normally expressed throughout T cell development, with a Zap70 transgene driven by the adenosine deaminase (ADA) gene enhancer, which is active in CD4(+)CD8(+) thymocytes but inactive in CD4(+) or CD8(+) single-positive (SP) thymocytes. In such mice, termination of Zap70 expression impaired TCR signal transduction and arrested thymocyte development after the initiation, but before the completion, of positive selection. Arrested thymocytes had terminated Rag gene expression and up-regulated TCR and Bcl-2 expression, but failed to differentiate into mature CD4 or CD8 SP thymocytes, to be rescued from death by neglect or to sustain interleukin 7R alpha expression. These observations identify a TCR-dependent proofreading mechanism that verifies thymocyte TCR specificity and differentiation choices before the completion of positive selection.
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Affiliation(s)
- Xiaolong Liu
- Laboratory of Immune Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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30
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Abstract
CD4 gene regulation provides an ideal model for understanding the molecular events that drive T cell development. In this paper we use a transgenic approach to identify a CD4 LCR containing a stage-specific thymocyte enhancer (TE) and a region that protects against position effect variegation. Surprisingly, the TE acts indirectly through the previously defined proximal enhancer and is strongly induced upon commitment to the T cell lineage. We also describe a complex series of hierarchical control element interactions that orchestrate CD4 expression throughout thymopoiesis. These data provide a framework for understanding how CD4 gene expression is regulated in response to lineage commitment decisions.
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Affiliation(s)
- Matthew Adlam
- Department of Microbiology, 701 West 168th Street, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA.
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31
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Harker N, Naito T, Cortes M, Hostert A, Hirschberg S, Tolaini M, Roderick K, Georgopoulos K, Kioussis D. The CD8alpha gene locus is regulated by the Ikaros family of proteins. Mol Cell 2002; 10:1403-15. [PMID: 12504015 DOI: 10.1016/s1097-2765(02)00711-6] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Ikaros family members are important regulatory factors in lymphocyte development. Here we show that Ikaros may play an important role in CD4 versus CD8 lineage commitment decisions by demonstrating: (1) that it binds to regulatory elements in the endogenous CD8alpha locus in vivo using thymocyte chromatin immunoprecipitations, (2) that Ikaros suppresses position effect variegation of transgenes driven by CD8 regulatory elements, and (3) that mice with reduced levels of Ikaros and Aiolos show an apparent increase in CD4 populations with immature phenotype, i.e., cells that failed to activate the CD8alpha gene locus. We propose that Ikaros family members function as activators of the CD8alpha gene locus and that their associated activities are critical for appropriate chromatin remodeling transitions during thymocyte differentiation and lineage commitment.
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Affiliation(s)
- Nicola Harker
- Division of Molecular Immunology, National Institute for Medical Research, Medical Research Council, NW7 1AA, London, United Kingdom
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32
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Abstract
T cell lineage commitment as the double-positive (DP) thymocyte matures into the single-positive (SP) T cell requires the irreversible repression or maintenance of CD4 gene expression. Signals transmitted from the T cell antigen receptor (TCR) during thymic selection are believed to be linked to the transcriptional regulation of the CD4 gene; thus, a study of the factors that control CD4 gene expression may lead to further insight into the molecular mechanisms that drive T cell development. This review discusses the work conducted to date to identify and characterize the transcriptional control elements in the CD4 locus and the factors that mediate their function. From these studies, it is clear that the molecular mechanisms controlling CD4 gene expression are very complex and are controlled by many different signals as the thymocyte develops.
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Affiliation(s)
- Gerald Siu
- Department of Microbiology, College of Physicians and Surgeons, Columbia University, 701 West 168th Street, New York, NY 10032, USA.
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33
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Abstract
In some respects, our understanding of the cellular and molecular aspects of early T-cell differentiation is lagging behind that of B cells. Papers describing gene-knockout and reporter-transgenic mice in which thymocyte development is affected are often difficult to interpret. Progress in this field will be hampered unless a more detailed phenotypic and molecular analysis of progenitor thymocytes at the single-cell level is carried out.
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Affiliation(s)
- Rod Ceredig
- U548 INSERM, CEA-G, 17 rue des Martyrs, F-38054 Grenoble, France.
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34
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Ferone D, Pivonello R, Van Hagen PM, Dalm VASH, Lichtenauer-Kaligis EGR, Waaijers M, Van Koetsveld PM, Mooy DM, Colao A, Minuto F, Lamberts SWJ, Hofland LJ. Quantitative and functional expression of somatostatin receptor subtypes in human thymocytes. Am J Physiol Endocrinol Metab 2002; 283:E1056-66. [PMID: 12376335 DOI: 10.1152/ajpendo.00205.2001] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We recently demonstrated the expression of somatostatin (SS) and SS receptor (SSR) subtype 1 (sst1), sst2A, and sst3 in normal human thymic tissue and of sst1 and sst2A on isolated thymic epithelial cells (TEC). We also found an inhibitory effect of SS and octreotide on TEC proliferation. In the present study, we further investigated the presence and function of SSR in freshly purified human thymocytes at various stages of development. Thymocytes represent a heterogeneous population of lymphoid cells displaying different levels of maturation and characterized by specific cell surface markers. In this study, we first demonstrated specific high-affinity 125I-Tyr(11)-labeled SS-14 binding on thymocyte membrane homogenates. Subsequently, by RT-PCR, sst2A and sst3 mRNA expression was detected in the whole thymocyte population. After separation of thymocytes into subpopulations, we found by quantitative RT-PCR that sst2A and sst3 are differentially expressed in intermediate/mature and immature thymocytes. The expression of sst3 mRNA was higher in the intermediate/mature CD3+ fraction compared with the immature CD2+CD3- one, whereas sst2A mRNA was less abundant in the intermediate/mature CD3+ thymocytes. In 7-day-cultured thymocytes, SSR subtype mRNA expression was lost. SS-14 significantly inhibited [3H]thymidine incorporation in all thymocyte cultures, indicating the presence of functional receptors. Conversely, octreotide significantly inhibited [3H]thymidine incorporation only in the cultures of immature CD2+CD3- thymocytes. Subtype sst3 is expressed mainly on the intermediate/mature thymocyte fraction, and most of these cells generally die by apoptosis. Because SS-14, but not octreotide, induced a significant increase in the percentage of apoptotic thymocytes, it might be that sst3 is involved in this process. Moreover, sst3 has recently been demonstrated on peripheral human T lymphocytes, which derive directly from mature thymocytes, and SS analogs may induce apoptosis in these cells. Interestingly, CD14+ thymic cells, which are cells belonging to the monocyte-macrophage lineage, selectively expressed sst2A mRNA. Finally, SSR expression in human thymocytes seems to follow a developmental pathway. The heterogeneous expression of SSR within the human thymus on specific cell subsets and the endogenous production of SS as well as SS-like peptides emphasize their role in the bidirectional interactions between the main cell components of the thymus involved in intrathymic T cell maturation.
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Affiliation(s)
- Diego Ferone
- Department of Internal Medicine, Erasmus Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands.
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Boyer O, Marodon G, Cohen JL, Lejeune L, Irinopoulou T, Liblau R, Bruneval P, Klatzmann D. Human CD4 expression at the late single-positive stage of thymic development supports T cell maturation and peripheral export in CD4-deficient mice. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 169:4347-53. [PMID: 12370367 DOI: 10.4049/jimmunol.169.8.4347] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Positive selection of developing thymocytes is initiated at the double-positive (DP) CD4(+)CD8(+) stage of their maturation. Accordingly, expression of a human CD4 (hCD4) transgene beginning at the DP stage has been shown to restore normal T cell development and function in CD4-deficient mice. However, it is unclear whether later onset CD4 expression would still allow such a restoration. To investigate this issue, we used transgenic mice in which a hCD4 transgene is not expressed on DP, but only on single-positive cells. By crossing these animals with CD4-deficient mice, we show that late hCD4 expression supports the maturation of T cell precursors and the peripheral export of mature TCRalphabeta(+) CD8(-) T cells. These results were confirmed in two different MHC class II-restricted TCR transgenic mice. T cells arising by this process were functional in the periphery because they responded to agonist peptide in vivo. Interestingly, thymocytes of these mice appeared refractory to peptide-induced negative selection. Together, these results indicate that the effect of CD4 on positive selection of class II-restricted T cells extends surprisingly late into the maturation process by a previously unrecognized pathway of differentiation, which might contribute to the generation of autoreactive T cells.
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Affiliation(s)
- Olivier Boyer
- Laboratoire de Biologie et Thérapeutique des Pathologies Immunitaires and Centre National de la Recherche Scientifique Unité Mixte de Recherche 7087, Hôpital Pitié-Salpêtrière, 83 boulevard de l'hôpital, F-75013 Paris, France
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36
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Rodriguez JW, Kohan MJ, King LC, Kirlin WG. Detection of DNA adducts in developing CD4+ CD8+ thymocytes and splenocytes following in utero exposure to benzo[a]pyrene. Immunopharmacol Immunotoxicol 2002; 24:365-81. [PMID: 12375734 DOI: 10.1081/iph-120014723] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Environmental carcinogen exposure may play an important role in the incidence of cancer in children. In addition to environmental pollutants, maternal smoking during pregnancy may be a contributing factor. Major carcinogenic components of cigarette smoke and other combustion by-products in the environment include polycyclic aromatic hydrocarbons (PAH). Mouse offspring exposed during midpregnancy to the PAH, benzo[a]pyrene (B[a]P), show significant deficiencies in their immune functions, observed in late gestation which persist for at least 18 months. Tumor incidences in these progeny are 8 to 10-fold higher than in controls. We have demonstrated a significant reduction in thymocytes (CD4+ CD8+, CD4+ CD8+ Vbeta8+, CD4+ CD8+ Vgamma2+) from newborn and splenocytes (CD4+ CD8+) from 1-week-old mouse progeny exposed to B[a]P in utero. To investigate possible causes of the observed T cell reduction, we analyzed the thymocytes and splenocytes from progeny and maternal tissues for the presence of B[a]P-DNA adducts. Adducts were detected in maternal, placental and offspring lymphoid tissues at day 19 of gestation, at birth and 1-wk after birth. The presence of B[a]P-DNA adducts in immature T cells may, in part, explain the previously observed T cell immunosuppression and tumor susceptibility in mice exposed to B[a]P in utero. The effects of DNA lesions on progeny T cells may include interference with normal T-cell development. These results provide a possible explanation for the relationship between maternal smoking during pregnancy and childhood carcinogenesis.
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Affiliation(s)
- J W Rodriguez
- Dept. of Microbiology and Immunology, Universidad Central del Caribe, Bayamon, PR 00960, USA
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37
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Inoue T, Horii I. Effects on fetal thymocyte populations and postnatal T-cell-dependent immune functions after maternal exposure to 5-fluorouracil during pregnancy in mice. J Toxicol Sci 2002; 27:79-86. [PMID: 12058450 DOI: 10.2131/jts.27.79] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
5-Fluorouracil (5-FU) is a cytostatic anti-tumor drug which is known to have immunosuppressive activities. To assess the immunotoxic effects of 5-FU on fetal thymocyte populations and immune functions after birth, pregnant C57BL/6 mice were orally administered vehicle or 17 mg/kg/day of 5-FU during gestational days (GD) from 6 to 14. The fetal thymocyte populations were analyzed with flow cytometry (CD4/CD8 double staining), and immune functions (a mixed lymphocyte reaction, in vitro cytotoxic T-cell response, in vitro antibody-forming response) after birth were measured. Fetal thymus weight and thymocyte numbers were decreased by 5-FU administration. The decrease of the thymocytes was due mainly to the decrease of small CD4CD8 double positive (DP) thymocytes. The thymocyte numbers and populations recovered to the normal level 1 week after birth. The mixed lymphocyte response at the 6th week after birth tended to be slightly lower than the control levels, but the cytotoxic T-cell response and the antibody-forming response were the same as the control levels. These results suggest that immune functions might recover after birth, although maternal administration of 5-FU has a suppressive effect on fetal thymocyte maturation.
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Affiliation(s)
- Tomoaki Inoue
- Department of Preclinical Science, Nippon Roche Research Center, 200 Kajiwara, Kamakura, Kanagawa 247-8530, Japan
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38
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Garefalaki A, Coles M, Hirschberg S, Mavria G, Norton T, Hostert A, Kioussis D. Variegated expression of CD8 alpha resulting from in situ deletion of regulatory sequences. Immunity 2002; 16:635-47. [PMID: 12049716 DOI: 10.1016/s1074-7613(02)00308-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The developmental and subset-specific expression of the CD8 genes is under the control of a complex array of regulatory elements distributed along the locus and characterized by DNaseI hypersensitivity. Here we describe the phenotype of mice in which hypersensitive sites 1 and 2 (HSS1 and 2) of DNaseI hypersensitive Cluster II (CII), which are located upstream of the CD8 alpha gene, were deleted by targeted homologous recombination of the endogenous locus. Knockout mice exhibit a variegated expression of the CD8 alpha gene, particularly among the immature CD4(+)8(+) TCR(lo) thymocyte population. We propose that HSS Cluster II regulatory elements are essential in ensuring initiation of chromatin remodeling and establishment of an open configuration in all developing thymocytes that undergo the double-negative to double-positive transition. Furthermore, these sequences contribute to the levels of expression of the CD8 alpha gene.
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Affiliation(s)
- Anna Garefalaki
- National Institute for Medical Research, The Ridgeway, London NW7 1AA, United Kingdom
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39
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Rulli K, Lenz J, Levy LS. Disruption of hematopoiesis and thymopoiesis in the early premalignant stages of infection with SL3-3 murine leukemia virus. J Virol 2002; 76:2363-74. [PMID: 11836414 PMCID: PMC135944 DOI: 10.1128/jvi.76.5.2363-2374.2002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A time course analysis of SL3-3 murine leukemia virus (SL3) infection in thymus and bone marrow of NIH/Swiss mice was performed to assess changes that occur during the early stages of progression to lymphoma. Virus was detectable in thymocytes, bone marrow, and spleen as early as 1 to 2 weeks postinoculation (p.i.). In bone marrow, virus infection was detected predominantly in immature myeloid or granulocytic cells. Flow cytometry revealed significant reductions of the Ter-119(+) and Mac-1(+) populations, and significant expansions of the Gr-1(+) and CD34(+) populations, between 2 and 4 weeks p.i. Analysis of colony-forming potential confirmed these findings. In the thymus, SL3 replication was associated with significant disruption in thymocyte subpopulation distribution between 4 and 7 weeks p.i. A significant thymic regression was observed just prior to the clonal outgrowth of tumor cells. Proviral long terminal repeats (LTRs) with increasing numbers of enhancer repeats were observed to accumulate exclusively in the thymus during the first 8 weeks p.i. Observations were compared to the early stages of infection with a virtually nonpathogenic SL3 mutant, termed SL3DeltaMyb5, which was shown by real-time PCR to be replication competent. Comparison of SL3 with SL3DeltaMyb5 implicated certain premalignant changes in tumorigenesis, including (i) increased proportions of Gr-1(+) and CD34(+) bone marrow progenitors, (ii) a significant increase in the proportion of CD4(-) CD8(-) thymocytes, (iii) thymic regression prior to tumor outgrowth, and (iv) accumulation of LTR enhancer variants. A model in which disrupted bone marrow hematopoiesis and thymopoiesis contribute to the development of lymphoma in the SL3-infected animal is discussed.
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Affiliation(s)
- Karen Rulli
- Department of Microbiology and Immunology, School of Medicine, Tulane University Health Sciences Center, New Orleans, Louisiana 70112, USA
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Tada M, Takahama Y, Abe K, Nakatsuji N, Tada T. Nuclear reprogramming of somatic cells by in vitro hybridization with ES cells. Curr Biol 2001; 11:1553-8. [PMID: 11591326 DOI: 10.1016/s0960-9822(01)00459-6] [Citation(s) in RCA: 580] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The resetting of a somatic epigenotype to a totipotential state has been demonstrated by successful animal cloning, via transplantation of somatic nuclei into enucleated oocytes. We have established an experimental system, which reproduces the nuclear reprogramming of somatic cells in vitro by fusing adult thymocytes with embryonic stem (ES) cells. Analysis of the lymphoid-cell-specific V-(D)-J DNA rearrangement of the T cell receptor and immunoglobin genes shows that the ES cells have hybridized with differentiated cells. In these ES cell hybrids, the inactivated X chromosome derived from a female thymocyte adopts some characteristics of an active X chromosome, including early replication timing and unstable Xist transcription. We also found that an Oct4-GFP transgene, which is normally repressed in thymocytes, is reactivated 48 hr after cell fusion. The pluripotency of the ES-thymocyte hybrid cells is shown in vivo, since they contribute to all three primary germ layers of chimeric embryos. The somatic DNA methylation pattern of the imprinted H19 and Igf2r genes is maintained in these hybrids, unlike hybrids between ES and EG (embryonic germ) cells in which the differential methylation is erased. Thus, ES cells have the capacity to reset certain aspects of the epigenotype of somatic cells to those of ES cells.
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MESH Headings
- Animals
- Cell Nucleus/metabolism
- DNA-Binding Proteins/genetics
- Female
- Gene Expression
- Gene Rearrangement, T-Lymphocyte
- Gene Rearrangement, alpha-Chain T-Cell Antigen Receptor
- Gene Rearrangement, beta-Chain T-Cell Antigen Receptor
- Gene Rearrangement, delta-Chain T-Cell Antigen Receptor
- Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor
- Hybrid Cells
- Mice
- Octamer Transcription Factor-3
- RNA
- RNA, Long Noncoding
- RNA, Untranslated/genetics
- Receptor, IGF Type 2/genetics
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, gamma-delta/genetics
- Recombinant Fusion Proteins/genetics
- Stem Cells
- Transcription Factors/genetics
- X Chromosome/physiology
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Affiliation(s)
- M Tada
- Precursory Research for Embryonic Science and Technology (PRESTO), JST, Kawaguchi-shi, Japan
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41
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Gallagher M, Obeïd P, Marche PN, Jouvin-Marche E. Both TCR alpha and TCR delta chain diversity are regulated during thymic ontogeny. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:1447-53. [PMID: 11466364 DOI: 10.4049/jimmunol.167.3.1447] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
TCRalpha and TCRdelta chains are coded by a common genetic locus using a single set of V gene segments (ADV segments). This article addresses the question of regulation of the use of the ADV segments by the TCRalpha and TCRdelta chains. Using both qualitative and quantitative analyses we have studied the use of 23 ADV gene families as part of TCRalpha and TCRdelta transcripts. A number of previously undetected rearrangement and transcription events are described, indicating that the intrathymic TCRdelta repertoire is much more diverse than previously supposed. Repertoire analysis at several developmental time points allowed the description of regulated waves of ADV gene use, not only for TCRdelta chains, but also for TCRalpha chains, during thymic ontogeny. Control of these waves appears to be linked directly to the ADV segments and their local chromatin environment, which may change over the course of T cell differentiation.
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MESH Headings
- Animals
- Cell Differentiation/genetics
- Cell Differentiation/immunology
- Gene Frequency/immunology
- Gene Rearrangement, alpha-Chain T-Cell Antigen Receptor/immunology
- Gene Rearrangement, delta-Chain T-Cell Antigen Receptor/immunology
- Mice
- Mice, Inbred BALB C
- Multigene Family/immunology
- Polymerase Chain Reaction
- Receptors, Antigen, T-Cell, alpha-beta/biosynthesis
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/isolation & purification
- Receptors, Antigen, T-Cell, gamma-delta/biosynthesis
- Receptors, Antigen, T-Cell, gamma-delta/genetics
- Receptors, Antigen, T-Cell, gamma-delta/isolation & purification
- Thymus Gland/cytology
- Thymus Gland/immunology
- Thymus Gland/metabolism
- Transcription, Genetic/immunology
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Affiliation(s)
- M Gallagher
- Institut National de la Santé et de la Recherche Médical, Unité 548, Commissariat à l'Energie Atomique de Grenoble, Université Joseph Fourier, Grenoble, France
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42
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Yoshimura FK, Wang T. Role of the LTR region between the enhancer and promoter in mink cell focus-forming murine leukemia virus pathogenesis. Virology 2001; 283:121-31. [PMID: 11312668 DOI: 10.1006/viro.2001.0879] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Long terminal repeat (LTR) sequences are important determinants of mink cell focus-forming (MCF) murine leukemia virus pathogenesis. These sequences include the enhancer and sequences between the enhancer and promoter (DEN). In a previous study we showed that a virus missing the DEN region in its LTR was severely attenuated in its ability to induce thymic lymphoma. In this study we observed that a virus with an LTR consisting of DEN but no enhancer sequences was pathogenic. We compared the pathogenicity of this DEN virus with other LTR mutant MCF13 viruses that contained a single enhancer (1R) or a single enhancer plus DEN (1R + DEN). All LTR mutant viruses generated thymic lymphoma, however, at a much lower incidence and with a longer latency compared with wild-type (WT) MCF13 virus. DEN virus replication in the thymus was the lowest compared with the 1R and 1R + DEN viruses. Viral replication in a different thymic subpopulation could not explain the decreased pathogenicity of the LTR mutant viruses compared with WT virus. However, lower levels of mutant virus replication in the thymus compared with WT during the preleukemic period may contribute to the attenuation of pathogenicity. The phenotype of tumors induced by the mutant viruses was similar and differed from tumors induced by WT virus by the presence of CD3(-)CD4(-)CD8(-) cells. Analysis of LTR sequences of infectious virus rescued from tumors induced by the 1R and 1R + DEN viruses showed that amplification of enhancer sequences had occurred during tumor development. The lack of DEN virus expression by tumor cells led us to propose that DEN sequences may play a role at an early step in tumorigenesis.
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Affiliation(s)
- F K Yoshimura
- Department of Immunology and Microbiology, Wayne State University, 540 E. Canfield Ave., Detroit, MI 48201, USA.
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43
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Miracle AL, Anderson MK, Litman RT, Walsh CJ, Luer CA, Rothenberg EV, Litman GW. Complex expression patterns of lymphocyte-specific genes during the development of cartilaginous fish implicate unique lymphoid tissues in generating an immune repertoire. Int Immunol 2001; 13:567-80. [PMID: 11282996 DOI: 10.1093/intimm/13.4.567] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Cartilaginous fish express canonical B and T cell recognition genes, but their lymphoid organs and lymphocyte development have been poorly defined. Here, the expression of Ig, TCR, recombination-activating gene (Rag)-1 and terminal deoxynucleosidase (TdT) genes has been used to identify roles of various lymphoid tissues throughout development in the cartilaginous fish, Raja eglanteria (clearnose skate). In embryogenesis, Ig and TCR genes are sharply up-regulated at 8 weeks of development. At this stage TCR and TdT expression is limited to the thymus; later, TCR gene expression appears in peripheral sites in hatchlings and adults, suggesting that the thymus is a source of T cells as in mammals. B cell gene expression indicates more complex roles for the spleen and two special organs of cartilaginous fish-the Leydig and epigonal (gonad-associated) organs. In the adult, the Leydig organ is the site of the highest IgM and IgX expression. However, the spleen is the first site of IgM expression, while IgX is expressed first in gonad, liver, Leydig and even thymus. Distinctive spatiotemporal patterns of Ig light chain gene expression also are seen. A subset of Ig genes is pre-rearranged in the germline of the cartilaginous fish, making expression possible without rearrangement. To assess whether this allows differential developmental regulation, IgM and IgX heavy chain cDNA sequences from specific tissues and developmental stages have been compared with known germline-joined genomic sequences. Both non-productively rearranged genes and germline-joined genes are transcribed in the embryo and hatchling, but not in the adult.
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Affiliation(s)
- A L Miracle
- University of South Florida, Department of Pediatrics, Children's Research Institute, 140 Seventh Avenue South, St Petersburg, FL 33701, USA
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44
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Le PT, Adams KL, Zaya N, Mathews HL, Storkus WJ, Ellis TM. Human thymic epithelial cells inhibit IL-15- and IL-2-driven differentiation of NK cells from the early human thymic progenitors. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:2194-201. [PMID: 11160272 DOI: 10.4049/jimmunol.166.4.2194] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
T/NK progenitors are present in the thymus; however, the thymus predominantly promotes T cell development. In this study, we demonstrated that human thymic epithelial cells (TEC) inhibit NK cell development. Most ex vivo human thymocytes express CD1a, indicating that thymic progenitors are predominantly committed to the T cell lineage. In contrast, the CD1a(-)CD3(-)CD56(+) NK population comprises only 0.2% (n = 7) of thymocytes. However, we observed increases in the percentage (20- to 25-fold) and absolute number (13- to 71-fold) of NK cells when thymocytes were cultured with mixtures of either IL-2, IL-7, and stem cell factor or IL-15, IL-7, and stem cell factor. TEC, when present in the cultures, inhibited the increases in the percentage (3- to 10-fold) and absolute number (3- to 25-fold) of NK cells. Furthermore, we show that TEC-derived soluble factors inhibit generation of NK-CFU and inhibit IL15- or IL2-driven NK cell differentiation from thymic CD34(+) triple-negative thymocytes. The inhibitory activity was found to be associated with a 8,000- to 30,000 Da fraction. Thus, our data demonstrate that TEC inhibit NK cell development from T/NK CD34(+) triple negative progenitors via soluble factor(s), suggesting that the human thymic microenvironment not only actively promotes T cell maturation but also controls the development of non-T lineage cells such as the NK lineage.
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Affiliation(s)
- P T Le
- Department of Cell Biology, Neurobiology, and Anatomy and the Program in Immunology for Aging, Stritch School of Medicine, Loyola University Chicago Medical Center, Maywood, IL 60153, USA.
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45
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T-lymphocyte maturation abnormalities in uninfected newborns and children with vertical exposure to HIV. Blood 2000. [DOI: 10.1182/blood.v96.12.3866] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Cell-mediated immunity and T-lymphocyte maturation are impaired in HIV-infected children. These abnormalities would be detected in HIV-uninfected offspring of HIV women (seroreverters [SR]) if HIV or its soluble proteins could cross the placental barrier. Immunophenotypic analyses were performed in 20 healthy HIV-uninfected newborns of HIV-infected mothers (SR), and in 14 healthy newborns of HIV-negative women (UC). The same analyses were performed in 3 groups of older children: SR (n = 41); UC (n = 15); and HIV-infected children (n = 25). Antigen-specific cells were evaluated with ELISpot and fluorimetric analyses; IL-7 serum concentration was measured by enzyme-linked immunosorbent assay (ELISA). Results showed that in SR newborns: (1) the CD4/CD8 ratio was reduced, (2) CD4+ and CD8+ naive T-cell percentages were decreased, (3) percentage of activated CD8+ T cells was increased, and (4) percentages of CD3+/4−/8− (DN) and DN/25−/44+ were augmented. These abnormalities were partially retained in older SR children. CD4+ and CD8+ HIV-specific cells were detected in a portion of newborn SRs but not in older SRs. Serum IL-7 was augmented both in newborn and older SRs. Cell-mediated immunity and T-cell maturation are altered even in HIV-uninfected newborns of HIV-infected mothers; these abnormalities persist over time. The biologic significance of these observations and potential subsequent clinical events should be investigated in larger cohorts of seroreverters.
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Abstract
Cell-mediated immunity and T-lymphocyte maturation are impaired in HIV-infected children. These abnormalities would be detected in HIV-uninfected offspring of HIV women (seroreverters [SR]) if HIV or its soluble proteins could cross the placental barrier. Immunophenotypic analyses were performed in 20 healthy HIV-uninfected newborns of HIV-infected mothers (SR), and in 14 healthy newborns of HIV-negative women (UC). The same analyses were performed in 3 groups of older children: SR (n = 41); UC (n = 15); and HIV-infected children (n = 25). Antigen-specific cells were evaluated with ELISpot and fluorimetric analyses; IL-7 serum concentration was measured by enzyme-linked immunosorbent assay (ELISA). Results showed that in SR newborns: (1) the CD4/CD8 ratio was reduced, (2) CD4+ and CD8+ naive T-cell percentages were decreased, (3) percentage of activated CD8+ T cells was increased, and (4) percentages of CD3+/4−/8− (DN) and DN/25−/44+ were augmented. These abnormalities were partially retained in older SR children. CD4+ and CD8+ HIV-specific cells were detected in a portion of newborn SRs but not in older SRs. Serum IL-7 was augmented both in newborn and older SRs. Cell-mediated immunity and T-cell maturation are altered even in HIV-uninfected newborns of HIV-infected mothers; these abnormalities persist over time. The biologic significance of these observations and potential subsequent clinical events should be investigated in larger cohorts of seroreverters.
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47
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Mulder GB, Manley N, Grant J, Schmidt K, Zeng W, Eckhoff C, Maggio-Price L. Effects of excess vitamin A on development of cranial neural crest-derived structures: a neonatal and embryologic study. TERATOLOGY 2000; 62:214-26. [PMID: 10992263 DOI: 10.1002/1096-9926(200010)62:4<214::aid-tera7>3.0.co;2-n] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Vitamin A and its metabolites have been shown to be teratogenic in animals and humans producing defects of neural crest derived structures that include abnormalities of the craniofacial skeleton, heart, and thymus. Our prior studies with retinoic acid have established that gestational day (gd) 9 is a sensitive embryonic age in the mouse for inducing craniofacial and thymic defects. METHODS We exposed pregnant mice to variable doses of vitamin A (retinyl acetate) on gd 9 and embryos were evaluated for changes in developing pharyngeal arch and pouch morphology, neural crest cell migration and marker gene expression. Additionally, we investigated whether a single organ system was more sensitive to low doses of vitamin A and could potentially be used as an indicator of vitamin A exposure during early gestation. RESULTS High (100 mg/kg) and moderate (50 and 25 mg/kg) doses of vitamin A resulted in significant craniofacial, cardiac outflow tract and thymic abnormalities. Low doses of vitamin A (10 mg/kg) produced craniofacial and thymic abnormalities that were mild and of low penetrance. Exposed embryos showed morphologic changes in the 2nd and 3rd pharyngeal arches and pouches, changes in neural crest migration, abnormalities in cranial ganglia, and altered expression of Hoxa3. CONCLUSIONS These animal studies, along with recent epidemiologic reports on human teratogenicity with vitamin A, raise concerns about the potential for induction of defects (perhaps subtle) in offspring of women ingesting even moderate to low amounts of supplemental vitamin A during the early gestational period.
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Affiliation(s)
- G B Mulder
- University Laboratory Animal Resources, University of California, Irvine, California 92697, USA
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Yoshimura FK, Wang T, Yu F, Kim HR, Turner JR. Mink cell focus-forming murine leukemia virus infection induces apoptosis of thymic lymphocytes. J Virol 2000; 74:8119-26. [PMID: 10933722 PMCID: PMC112345 DOI: 10.1128/jvi.74.17.8119-8126.2000] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In a previous study we identified the subpopulations of thymus cells that were infected by the lymphomagenic MCF13 murine leukemia virus (MLV) (F. K. Yoshimura, T. Wang, and M. Cankovic, J. Virol. 73:4890-4898, 1999) and observed an effect on thymus size by virus infection. In this report we describe our results which demonstrate that MCF13 MLV infection of thymuses reduced the number of T lymphocytes in this organ. Histological examination showed diffuse lymphocyte depletion, which was most striking in the CD4(+) CD8(+) lymphocyte-enriched cortical zone. Consistent with this, flow cytometric analysis showed that the lymphocytes which were depleted were predominantly the immature CD3(-) CD4(+) CD8(+) and CD3(+) CD4(+) CD8(+) cells. A comparison of the percentages of live, apoptotic, and dead cells of the gp70(+) and gp70(-) thymic lymphocytes suggested that this effect on thymus cellularity is a result of virus infection. Studies of the survival of thymic T lymphocytes in culture showed that cells from MCF13 MLV-inoculated mice underwent greater apoptosis and death than cells from control animals. Assays for apoptosis included 7-amino-actinomycin D staining, DNA fragmentation, and cleavage of caspase-3 and poly(ADP-ribose) polymerase proenzymes. Our results suggest that apoptosis of thymic lymphocytes by virus infection is an important step in the early stages of MCF13 MLV tumorigenesis.
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Affiliation(s)
- F K Yoshimura
- Department of Immunology and Microbiology and the Karmanos Cancer Institute, Wayne State University, Detroit, Michigan 48201, USA.
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Abstract
Abstract
Gap junctions are intercellular channels, formed by individual structural units known as connexins (Cx), that allow the intercellular exchange of various messenger molecules. The finding that numbers of Cx43-type gap junctions in bone marrow are elevated during establishment and regeneration of the hematopoietic system has led to the hypothesis that expression of Cx43 is critical during the initiation of blood cell formation. To test this hypothesis, lymphoid and myeloid development were examined in mice with a targeted disruption of the gene encoding Cx43. Because Cx43−/− mice die perinatally, initial analyses were performed on Cx43−/−, Cx43+/−, and Cx43+/+ embryos and newborns. The data indicate that lack of Cx43 expression during embryogenesis compromises the terminal stages of primary T and B lymphopoiesis. Cx43−/− embryos and neonates had a reduced frequency of CD4+ and T-cell receptor-expressing thymocytes and surface IgM+cells compared to their Cx43+/+ littermates. Surprisingly, Cx43+/− embryos/neonates also showed defects in B- and T-cell development similar to those observed in Cx43−/− littermates, but their hematopoietic system was normal at 4 weeks of age. However, the regeneration of lymphoid and myeloid cells was severely impaired in the Cx43+/− mice after cytoablative treatment. Taken together, these data indicate that loss of a single Cx43 allele can affect blood cell formation. Finally, the results of reciprocal bone marrow transplants between Cx43+/+ and Cx43+/− mice and examination of hematopoietic progenitors and stromal cells in vitro indicates that the primary effects of Cx43 are mediated through its expression in the hematopoietic microenvironment.
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Expression of connexin 43 (Cx43) is critical for normal hematopoiesis. Blood 2000. [DOI: 10.1182/blood.v96.3.917.015k45_917_924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Gap junctions are intercellular channels, formed by individual structural units known as connexins (Cx), that allow the intercellular exchange of various messenger molecules. The finding that numbers of Cx43-type gap junctions in bone marrow are elevated during establishment and regeneration of the hematopoietic system has led to the hypothesis that expression of Cx43 is critical during the initiation of blood cell formation. To test this hypothesis, lymphoid and myeloid development were examined in mice with a targeted disruption of the gene encoding Cx43. Because Cx43−/− mice die perinatally, initial analyses were performed on Cx43−/−, Cx43+/−, and Cx43+/+ embryos and newborns. The data indicate that lack of Cx43 expression during embryogenesis compromises the terminal stages of primary T and B lymphopoiesis. Cx43−/− embryos and neonates had a reduced frequency of CD4+ and T-cell receptor-expressing thymocytes and surface IgM+cells compared to their Cx43+/+ littermates. Surprisingly, Cx43+/− embryos/neonates also showed defects in B- and T-cell development similar to those observed in Cx43−/− littermates, but their hematopoietic system was normal at 4 weeks of age. However, the regeneration of lymphoid and myeloid cells was severely impaired in the Cx43+/− mice after cytoablative treatment. Taken together, these data indicate that loss of a single Cx43 allele can affect blood cell formation. Finally, the results of reciprocal bone marrow transplants between Cx43+/+ and Cx43+/− mice and examination of hematopoietic progenitors and stromal cells in vitro indicates that the primary effects of Cx43 are mediated through its expression in the hematopoietic microenvironment.
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