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Sample records for normal t-cell development

  1. Normal development and activation but altered cytokine production of Fyn-deficient CD4+ T cells

    PubMed Central

    Mamchak, Alusha A.; Sullivan, Brandon M.; Hou, Baidong; Lee, Linda M.; Gilden, Julia K.; Krummel, Matthew F.; Locksley, Richard M.; DeFranco, Anthony L.

    2009-01-01

    The Src family kinase, Fyn, is expressed in T cells and has been shown to phosphorylate proteins involved in TCR signaling, cytoskeletal reorganization and IL-4 production. Fyn-deficient mice have greatly decreased numbers of NKT cells, and have thymocytes and T cells with compromised responses following antibody cross-linking of their TCRs. Here we have addressed the role of Fyn in peptide/MHC class II-induced CD4+ T cell responses. In Fyn-deficient mice, CD4+ T cells expressing the DO11.10 TCR transgene developed normally, and the number and phenotype of naïve and regulatory DO11.10+CD4+ T cells in the periphery were comparable with their wild type counterparts. Conjugation with Ovap323-339 loaded APCs, and the subsequent proliferation in vitro or in vivo of DO11.10+Fyn-deficient CD4+ T cells was virtually indistinguishable from the response of DO11.10+ wild type CD4+ T cells. Proliferation of Fyn-deficient T cells was not more dependent on co-stimulation through CD28. In addition, we have found that differentiation, in vitro or in vivo, of transgenic CD4+ Fyn-deficient T cells into IL-4 secreting effector cells was unimpaired, and under certain conditions DO11.10+Fyn-deficient CD4+ T cells were more potent cytokine-producing cells than DO11.10+ wild type CD4+ T cells. These data demonstrate that ablation of Fyn expression does not alter most antigen-driven CD4+ T cell responses with the exception of cytokine production, which under some circumstances, is enhanced in Fyn-deficient CD4+ T cells. PMID:18832694

  2. Recapitulation of normal and abnormal BioBreeding rat T cell development in adult thymus organ culture.

    PubMed

    Whalen, B J; Weiser, P; Marounek, J; Rossini, A A; Mordes, J P; Greiner, D L

    1999-04-01

    Congenitally lymphopenic diabetes-prone (DP) BioBreeding (BB) rats develop spontaneous T cell-dependent autoimmunity. Coisogenic diabetes-resistant (DR) BB rats are not lymphopenic and are free of spontaneous autoimmune disease, but become diabetic in response to depletion of RT6+ T cells. The basis for the predisposition to autoimmunity in BB rats is unknown. Abnormal T cell development in DP-BB rats can be detected intrathymically, and thymocytes from DR-BB rats adoptively transfer diabetes. The mechanisms underlying these T cell developmental abnormalities are not known. To study these processes, we established adult thymus organ cultures (ATOC). We report that cultured DR- and DP-BB rat thymi generate mature CD4 and CD8 single-positive cells with up-regulated TCRs. DR-BB rat cultures also generate T cells that express RT6. In contrast, DP-BB rat cultures generate fewer CD4+, CD8+, and RT6+ T cells. Analysis of the cells obtained from ATOC suggested that the failure of cultured DP-BB rat thymi to generate T cells with a mature phenotype is due in part to an increased rate of apoptosis. Consistent with this inference, we observed that addition of the general caspase inhibitor Z-VAD-FMK substantially increases the number of both mature and immature T cells produced by DP-BB rat ATOC. We conclude that cultured DR-BB and DP-BB rat thymi, respectively, recapitulate the normal and abnormal T cell developmental kinetics and phenotypes observed in these animals in vivo. Such cultures should facilitate identification of the underlying pathological processes that lead to immune dysfunction and autoimmunity in BB rats. PMID:10201921

  3. T cell development in normal and thymopentin-treated nude mice.

    PubMed

    Ranges, G E; Goldstein, G; Boyse, E A; Schield, M P

    1982-10-01

    The extent and diversity of T cell differentiation in nude athymic mice are matters of dispute. In this study, we examined the splenic T cell population of pathogen-free and germ-free nu/nu mice, treated or not treated with the pentapeptide analogue of thymopoietin (TP-5), in terms of TL, Qa-1, and Lyt phenotypes. At all ages, 50-60% of nu/nu splenocytes, enriched for T lymphocytes by removal of sIg+ cells, expressed T markers, as compared with greater than 85% in normal mice. At 2 mo of age, all nu/nu splenic T cells expressed the surface phenotype TL+:Thy-1+:Ly-123. This is abnormal in two respects: first, because expression of TL is normally confined to thymocytes; and second, because there was no evidence of the usual diversification into the subsets Ly-1 and Ly-23. From 10 wk of age onwards, diversification into Ly subsets was evident in nu/nu spleen, although the usual predominance of Ly-1 over Ly-123 cells was not attained, and some TL+ cells persisted. Also, the ratio of Qa-1+ to Qa-1- cells rose progressively to as high as 4:1 at 4-6 mo, in contrast to the usual ratio of approximately 1:1, regardless of age. In the spleens of nu/nu mice treated with TP-5 from 5-8 weeks of age and tested 1 wk later, the proportion of T cells was raised, though not to normal levels, the number of TL+ cells was reduced, and there was diversification into Ly sets. PMID:6759606

  4. Approaches to Study Human T Cell Development.

    PubMed

    Dolens, Anne-Catherine; Van de Walle, Inge; Taghon, Tom

    2016-01-01

    Not only is human T cell development characterized by unique changes in surface marker expression, but it also requires specific growth factors and conditions to mimic and study T cell development in vitro. In this chapter, we provide an overview of the specific aspects that need attention when performing T cell differentiation cultures with human progenitors. PMID:26294413

  5. Studying T Cell Development in Thymic Slices.

    PubMed

    Ross, Jenny O; Melichar, Heather J; Halkias, Joanna; Robey, Ellen A

    2016-01-01

    Recently, tissue slices have been adapted to study both mouse and human T cell development. Thymic slices combine and complement the strengths of existing organotypic culture systems to study thymocyte differentiation. Specifically, the thymic slice system allows for high throughput experiments and the ability to introduce homogenous developmental intermediate populations into an environment with a well-established cortex and medulla. These qualities make thymic slices a highly versatile and technically accessible model to study thymocyte development. Here we describe methods to prepare, embed, and slice thymic lobes to study T cell development in situ. PMID:26294404

  6. Ligand recognition during thymic development and ?? T cell function specification

    PubMed Central

    Meyer, Christina; Zeng, Xun; Chien, Yueh-hsiu

    2010-01-01

    ?? T cells develop in the thymus before entering the periphery. Recent work suggests that thymic development does little to constrain ?? T cell antigen specificities, but instead determines their effector fate. When triggered through the T cell receptor, ligand-naïve ?? T cells produce IL-17, ligand-experienced cells make IFN-? and those that are strongly self-reactive make IL-4. Importantly, ?? T cells are able to make cytokines immediately upon TCR engagement. These characteristics allow ?? T cells to initiate an acute inflammatory response to pathogens and to host antigens revealed by injury. These advances warrant a fresh look at how ?? T cells may function in the immune system. PMID:20430644

  7. Genetic Tools to Study T Cell Development.

    PubMed

    Ciucci, Thomas; Vacchio, Melanie S; Bosselut, Rémy

    2016-01-01

    Genetics tools, and especially the ability to enforce, by transgenesis, or disrupt, by homologous recombination, gene expression in a cell-specific manner, have revolutionized the study of immunology and propelled the laboratory mouse as the main model to study immune responses. Perhaps more than any other aspect of immunology, the study of T cell development has benefited from these technologies. This brief chapter summarizes genetic tools specific to T cell development studies, focusing on mouse strains with lineage- and stage-specific expression of the Cre recombinase, or expressing unique antigen receptor specificities. It ends with a broader discussion of strategies to enforce ectopic lineage and stage-specific gene expression. PMID:26294396

  8. ?? T Cell-Dependent Regulatory T Cells Prevent the Development of Autoimmune Keratitis.

    PubMed

    Huang, Yafei; Yang, Zhifang; Huang, Chunjian; McGowan, Jessica; Casper, Tamara; Sun, Deming; Born, Willi K; O'Brien, Rebecca L

    2015-12-15

    To prevent potentially damaging inflammatory responses, the eye actively promotes local immune tolerance via a variety of mechanisms. Owing to trauma, infection, or other ongoing autoimmunity, these mechanisms sometimes fail, and an autoimmune disorder may develop in the eye. In mice of the C57BL/10 (B10) background, autoimmune keratitis often develops spontaneously, particularly in the females. Its incidence is greatly elevated in the absence of ?? T cells, such that ?80% of female B10.TCR?(-/-) mice develop keratitis by 18 wk of age. In this article, we show that CD8(+) ?? T cells are the drivers of this disease, because adoptive transfer of CD8(+), but not CD4(+), T cells to keratitis-resistant B10.TCR?/?(-/-) hosts induced a high incidence of keratitis. This finding was unexpected because in other autoimmune diseases, more often CD4(+) ?? T cells, or both CD4(+) and CD8(+) ?? T cells, mediate the disease. Compared with wild-type B10 mice, B10.TCR?(-/-) mice also show increased percentages of peripheral memory phenotype CD8(+) ?? T cells, along with an elevated frequency of CD8(+) ?? T cells biased to produce inflammatory cytokines. In addition, B10.TCR?-/- mice have fewer peripheral CD4(+) CD25(+) Foxp3(+) ?? regulatory T cells (Tregs), which express lower levels of receptors needed for Treg development and function. Together, these observations suggest that in B10 background mice, ?? T cells are required to generate adequate numbers of CD4(+) CD25(+) Foxp3(+) Tregs, and that in B10.TCR?(-/-) mice a Treg deficiency allows dysregulated effector or memory CD8(+) ?? T cells to infiltrate the cornea and provoke an autoimmune attack. PMID:26566677

  9. Histone Deacetylase 3 Is Required for Efficient T Cell Development.

    PubMed

    Stengel, Kristy R; Zhao, Yue; Klus, Nicholas J; Kaiser, Jonathan F; Gordy, Laura E; Joyce, Sebastian; Hiebert, Scott W; Summers, Alyssa R

    2015-11-15

    Hdac3 is a key target for Hdac inhibitors that are efficacious in cutaneous T cell lymphoma. Moreover, the regulation of chromatin structure is critical as thymocytes transition from an immature cell with open chromatin to a mature T cell with tightly condensed chromatin. To define the phenotypes controlled by Hdac3 during T cell development, we conditionally deleted Hdac3 using the Lck-Cre transgene. This strategy inactivated Hdac3 in the double-negative stages of thymocyte development and caused a significant impairment at the CD8 immature single-positive (ISP) stage and the CD4/CD8 double-positive stage, with few mature CD4(+) or CD8(+) single-positive cells being produced. When Hdac3(-/-) mice were crossed with Bcl-xL-, Bcl2-, or TCR?-expressing transgenic mice, a modest level of complementation was found. However, when the null mice were crossed with mice expressing a fully rearranged T cell receptor ?? transgene, normal levels of CD4 single-positive cells were produced. Thus, Hdac3 is required for the efficient transit from double-negative stage 4 through positive selection. PMID:26324326

  10. Partial defects of T cell development associated with poor T cell function

    PubMed Central

    Notarangelo, Luigi D.

    2013-01-01

    For many years, Severe Combined Immune Deficiency (SCID) diseases, characterized by virtual lack of circulating T cells and severe predisposition to infections since early in life, have been considered the prototypic forms of genetic defects of T cell development. More recently, advances in genome sequencing have allowed identification of a growing number of gene defects that cause severe, but incomplete, defects in T cell development and/or function. Along with recurrent and severe infections, and especially cutaneous viral infections, the clinical phenotype of these conditions is characterized by prominent immune dysregulation. PMID:23465662

  11. Conformational changes in the T cell receptor differentially determine T cell subset development in mice.

    PubMed

    Blanco, Raquel; Borroto, Aldo; Schamel, Wolfgang; Pereira, Pablo; Alarcon, Balbino

    2014-12-01

    In the thymus, immature T cells differentiate from common precursors to become T cells expressing either the ?? or ?? T cell receptor (TCR) complex. The CD3? subunit of the TCR complex is thought to transduce ligand-induced conformational changes in the TCR by recruiting the cytosolic adaptor protein Nck. To investigate the role of conformational changes in the TCR in T cell development, we generated mice with a germline mutation (C80G) in the extracellular domain of CD3?, which prevents the outside-in transmission of conformational changes in the TCR. The development of ?? T cells in the C80G mice was blocked at an early stage that depends on signaling by a precursor form of the TCR. In contrast, the C80G mutation did not impair the development of some subsets of ?? T cells, including V?1.1(+) cells; however, development of other ?? T cell subsets was blocked. A similar phenotype was observed in mice with a mutation in the cytoplasmic proline-rich sequence (PRS) of CD3?, the binding site for Nck. In a genetic complementation test, the PRS CD3? mutant failed to rescue the wild-type phenotype when expressed in heterozygosity with the C80G mutant. These data suggest that Nck may function as an effector of TCR conformational changes during T cell development. Additional experiments showed differential effects of the C80G mutation on the activation of TCR-dependent signaling pathways, which suggests that there are pathways that are either dependent on or independent of the transmission of conformational change in the receptor. PMID:25468995

  12. Conserved and divergent aspects of human T-cell development and migration in humanized mice

    PubMed Central

    Halkias, Joanna; Yen, Bonnie; Taylor, Kayleigh T; Reinhartz, Olaf; Winoto, Astar; Robey, Ellen A; Melichar, Heather J

    2015-01-01

    Humanized mice represent an important model to study the development and function of the human immune system. While it is known that mouse thymic stromal cells can support human T-cell development, the extent of interspecies cross-talk and the degree to which these systems recapitulate normal human T-cell development remain unclear. To address these questions, we compared conventional and non-conventional T-cell development in a neonatal chimera humanized mouse model with that seen in human fetal and neonatal thymus samples, and also examined the impact of a human HLA-A2 transgene expressed by the mouse stroma. Given that dynamic migration and cell–cell interactions are essential for T-cell differentiation, we also studied the intrathymic migration pattern of human thymocytes developing in a murine thymic environment. We found that both conventional T-cell development and intra-thymic migration patterns in humanized mice closely resemble human thymopoiesis. Additionally, we show that developing human thymocytes engage in short, serial interactions with other human hematopoietic-derived cells. However, non-conventional T-cell differentiation in humanized mice differed from both fetal and neonatal human thymopoiesis, including a marked deficiency of Foxp3+ T-cell development. These data suggest that although the murine thymic microenvironment can support a number of aspects of human T-cell development, important differences remain, and additional human-specific factors may be required. PMID:25744551

  13. Asymmetric cell division during T cell development controls downstream fate.

    PubMed

    Pham, Kim; Shimoni, Raz; Charnley, Mirren; Ludford-Menting, Mandy J; Hawkins, Edwin D; Ramsbottom, Kelly; Oliaro, Jane; Izon, David; Ting, Stephen B; Reynolds, Joseph; Lythe, Grant; Molina-Paris, Carmen; Melichar, Heather; Robey, Ellen; Humbert, Patrick O; Gu, Min; Russell, Sarah M

    2015-09-14

    During mammalian T cell development, the requirement for expansion of many individual T cell clones, rather than merely expansion of the entire T cell population, suggests a possible role for asymmetric cell division (ACD). We show that ACD of developing T cells controls cell fate through differential inheritance of cell fate determinants Numb and ?-Adaptin. ACD occurs specifically during the ?-selection stage of T cell development, and subsequent divisions are predominantly symmetric. ACD is controlled by interaction with stromal cells and chemokine receptor signaling and uses a conserved network of polarity regulators. The disruption of polarity by deletion of the polarity regulator, Scribble, or the altered inheritance of fate determinants impacts subsequent fate decisions to influence the numbers of DN4 cells arising after the ?-selection checkpoint. These findings indicate that ACD enables the thymic microenvironment to orchestrate fate decisions related to differentiation and self-renewal. PMID:26370500

  14. Using the Zebrafish Model to Study T Cell Development.

    PubMed

    Zhang, Yong; Wiest, David L

    2016-01-01

    While zebrafish have for some time been regarded as a powerful model organism with which to study early events in hematopoiesis, recent evidence suggests that it also ideal for unraveling the molecular requirements for T cell development in the thymus. Like mammals, zebrafish possess an adaptive immune system, comprising B lymphocytes as well as both the ?? and ?? lineages of T cells, which develop in the thymus. Moreover, the molecular processes underlying T cell development in zebrafish appear to be remarkably conserved. Thus, findings in the zebrafish model will be of high relevance to the equivalent processes in mammals. Finally, molecular processes can be interrogated in zebrafish far more rapidly than is possible in mammals because the zebrafish possesses many unique advantages. These unique attributes, and the methods by which they can be exploited to investigate the role of novel genes in T cell development, are described here. PMID:26294415

  15. Vitamin D receptor expression controls proliferation of naïve CD8+ T cells and development of CD8 mediated gastrointestinal inflammation

    PubMed Central

    2014-01-01

    Background Vitamin D receptor (VDR) deficiency contributes to the development of experimental inflammatory bowel disease (IBD) in several different models. T cells have been shown to express the VDR, and T cells are targets of vitamin D. In this article we determined the effects of VDR expression on CD8+ T cells. Results VDR KO CD8+ T cells, but not WT CD8+ T cells, induced colitis in Rag KO recipients. In addition, co-transfer of VDR KO CD8+ T cells with naïve CD4+ T cells accelerated colitis development. The more severe colitis was associated with rapidly proliferating naïve VDR KO CD8+ T cells and increased IFN-? and IL-17 in the gut. VDR KO CD8+ T cells proliferated in vitro without antigen stimulation and did not downregulate CD62L and upregulate CD44 markers following proliferation that normally occurred in WT CD8+ T cells. The increased proliferation of VDR KO CD8+ cells was due in part to the higher production and response of the VDR KO cells to IL-2. Conclusions Our data indicate that expression of the VDR is required to prevent replication of quiescent CD8+ T cells. The inability to signal through the VDR resulted in the generation of pathogenic CD8+ T cells from rapidly proliferating cells that contributed to the development of IBD. PMID:24502291

  16. Assessment of T Cell Development by Flow Cytometry.

    PubMed

    Lee, Jan Y M; Love, Paul E

    2016-01-01

    T cell development is a complex multistep process that requires the coordinated activation of distinct signaling responses and the regulated progression of developing cells (thymocytes) through key stages of maturation. Although sophisticated techniques such as fetal thymus organ culture, in vitro thymocyte culture, and multi-parameter flow cytometric analysis are now widely employed to evaluate thymocyte maturation by experienced laboratories, defects in T cell development can usually be identified with more simplified screening methods. Here, we provide a basic protocol for assessment of T cell development that will enable laboratories with access to a four parameter flow cytometer to screen mouse strains, including those generated from embryonic stem cells with targeted gene mutations, for thymocyte maturation defects. PMID:26294397

  17. The role of ICOS in the development of CD4 T cell help and the reactivation of memory T cells

    E-print Network

    , Spain 3 Institute of Stem Cell Research, University of Edinburgh, King's Buildings, Edinburgh, UK We of memory clones and long-term (10 wk) survival of memory cells, but defective expansion upon reactivationThe role of ICOS in the development of CD4 T cell help and the reactivation of memory T cells Simmi

  18. Humanized Mice to Study Human T Cell Development.

    PubMed

    Bonte, Sarah; Snauwaert, Sylvia; Vanhee, Stijn; Dolens, Anne-Catherine; Taghon, Tom; Vandekerckhove, Bart; Kerre, Tessa

    2016-01-01

    While in vitro models exist to study human T cell development, they still lack the precise environmental stimuli, such as the exact combination and levels of cytokines and chemokines, that are present in vivo. Moreover, studying the homing of hematopoietic stem (HSC) and progenitor (HPC) cells to the thymus can only be done using in vivo models. Although species-specific differences exist, "humanized" models are generated to circumvent these issues. In this chapter, we focus on the humanized mouse models that can be used to study early T cell development. Models that study solely mature T cells, such as the SCID-PBL (Tary-Lehmann et al., Immunol Today 16:529-533) are therefore not discussed here, but have recently been reviewed (Shultz et al., Nat Rev Immunol 12:786-798). PMID:26294414

  19. Normalizing glycosphingolipids restores function in CD4+ T cells from lupus patients.

    PubMed

    McDonald, Georgia; Deepak, Shantal; Miguel, Laura; Hall, Cleo J; Isenberg, David A; Magee, Anthony I; Butters, Terry; Jury, Elizabeth C

    2014-02-01

    Patients with the autoimmune rheumatic disease systemic lupus erythematosus (SLE) have multiple defects in lymphocyte signaling and function that contribute to disease pathogenesis. Such defects could be attributed to alterations in metabolic processes, including abnormal control of lipid biosynthesis pathways. Here, we reveal that CD4+ T cells from SLE patients displayed an altered profile of lipid raft-associated glycosphingolipids (GSLs) compared with that of healthy controls. In particular, lactosylceramide, globotriaosylceramide (Gb3), and monosialotetrahexosylganglioside (GM1) levels were markedly increased. Elevated GSLs in SLE patients were associated with increased expression of liver X receptor ? (LXR?), a nuclear receptor that controls cellular lipid metabolism and trafficking and influences acquired immune responses. Stimulation of CD4+ T cells isolated from healthy donors with synthetic and endogenous LXR agonists promoted GSL expression, which was blocked by an LXR antagonist. Increased GSL expression in CD4+ T cells was associated with intracellular accumulation and accelerated trafficking of GSL, reminiscent of cells from patients with glycolipid storage diseases. Inhibition of GSL biosynthesis in vitro with a clinically approved inhibitor (N-butyldeoxynojirimycin) normalized GSL metabolism, corrected CD4+ T cell signaling and functional defects, and decreased anti-dsDNA antibody production by autologous B cells in SLE patients. Our data demonstrate that lipid metabolism defects contribute to SLE pathogenesis and suggest that targeting GSL biosynthesis restores T cell function in SLE. PMID:24463447

  20. Regulatory T-Cell Development in the Human Thymus

    PubMed Central

    Caramalho, Íris; Nunes-Cabaço, Helena; Foxall, Russell B.; Sousa, Ana E.

    2015-01-01

    The thymus generates a lineage-committed subset of regulatory T-cells (Tregs), best identified by the expression of the transcription factor FOXP3. The development of thymus-derived Tregs is known to require high-avidity interaction with MHC-self peptides leading to the generation of self-reactive Tregs fundamental for the maintenance of self-tolerance. Notwithstanding their crucial role in the control of immune responses, human thymic Treg differentiation remains poorly understood. In this mini-review, we will focus on the developmental stages at which Treg lineage commitment occurs, and their spatial localization in the human thymus, reviewing the molecular requirements, including T-cell receptor and cytokine signaling, as well as the cellular interactions involved. An overview of the impact of described thymic defects on the Treg compartment will be provided, illustrating the importance of these in vivo models to investigate human Treg development. PMID:26284077

  1. T-cell accumulation and regulated on activation, normal T cell expressed and secreted upregulation in adipose tissue in obesity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Obesity is associated with chronic inflammation, which includes increased macrophage accumulation in adipose tissue (AT) and upregulation of chemokines and cytokines. T cells also play important roles in chronic inflammatory diseases such as atherosclerosis but have not been well studied in obesity....

  2. Development of ?? T Cells, the Special-Force Soldiers of the Immune System.

    PubMed

    Wiest, David L

    2016-01-01

    While the functions of ?? T cells in host resistance to pathogen infection are understood in far more detail than those of ?? lineage T cells, ?? T cells perform critical, essential functions during immune responses that cannot be compensated by ?? T cells. Accordingly, it is essential to understand how the development of ?? T cells is controlled so that their generation and function might be manipulated in future for therapeutic benefit. This introductory chapter will cover the basic processes that underlie ?? T cell development in the thymus, as well as the current understanding of how they are controlled. PMID:26294395

  3. Histone acetyltransferases and histone deacetylases in B- and T-cell development, physiology and malignancy

    PubMed Central

    Haery, Leila; Thompson, Ryan C.; Gilmore, Thomas D.

    2015-01-01

    The development of B and T cells from hematopoietic precursors and the regulation of the functions of these immune cells are complex processes that involve highly regulated signaling pathways and transcriptional control. The signaling pathways and gene expression patterns that give rise to these developmental processes are coordinated, in part, by two opposing classes of broad-based enzymatic regulators: histone acetyltransferases (HATs) and histone deacetylases (HDACs). HATs and HDACs can modulate gene transcription by altering histone acetylation to modify chromatin structure, and by regulating the activity of non-histone substrates, including an array of immune-cell transcription factors. In addition to their role in normal B and T cells, dysregulation of HAT and HDAC activity is associated with a variety of B- and T-cell malignancies. In this review, we describe the roles of HATs and HDACs in normal B- and T-cell physiology, describe mutations and dysregulation of HATs and HDACs that are implicated lymphoma and leukemia, and discuss HAT and HDAC inhibitors that have been explored as treatment options for leukemias and lymphomas. PMID:26124919

  4. Statistical Physics of T-Cell Development and Pathogen Specificity

    NASA Astrophysics Data System (ADS)

    Košmrlj, Andrej; Kardar, Mehran; Chakraborty, Arup K.

    2013-04-01

    In addition to an innate immune system that battles pathogens in a nonspecific fashion, higher organisms, such as humans, possess an adaptive immune system to combat diverse (and evolving) microbial pathogens. Remarkably, the adaptive immune system mounts pathogen-specific responses, which can be recalled upon reinfection with the same pathogen. It is difficult to see how the adaptive immune system can be preprogrammed to respond specifically to a vast and unknown set of pathogens. Although major advances have been made in understanding pertinent molecular and cellular phenomena, the precise principles that govern many aspects of an immune response are largely unknown. We discuss complementary approaches from statistical mechanics and cell biology that can shed light on how key components of the adaptive immune system, T cells, develop to enable pathogen-specific responses against many diverse pathogens. The mechanistic understanding that emerges has implications for how host genetics may influence the development of T cells with differing responses to the human immunodeficiency virus (HIV) infection.

  5. Bi-Allelic TCR? or ? Recombination Enhances T Cell Development but Is Dispensable for Antigen Responses and Experimental Autoimmune Encephalomyelitis

    PubMed Central

    Schuldt, Nathaniel J.; Auger, Jennifer L.; Hogquist, Kristin A.; Binstadt, Bryce A.

    2015-01-01

    Dual TCR?-expressing T cells outnumber dual TCR?-expressing cells by ~10:1. As a result, efforts to understand how dual TCR T cells impact immunity have focused on dual TCR? expression; dual TCR? expression remains understudied. We recently demonstrated, however, that dual TCR? expression accelerated disease in a TCR transgenic model of autoimmune arthritis through enhanced positive selection efficiency, indicating that dual TCR? expression, though rare, can impact thymic selection. Here we generated mice hemizygous for TCR?, TCR?, or both on the C57BL/6 background to investigate the impact bi-allelic TCR chain recombination has on T cell development, repertoire diversity, and autoimmunity. Lack of bi-allelic TCR? or TCR? recombination reduced ?? thymocyte development efficiency, and the absence of bi-allelic TCR? recombination promoted ?? T cell development. However, we observed no differences in the numbers of naïve and expanded antigen-specific T cells between TCR?+/-?+/- and wildtype mice, and TCR repertoire analysis revealed only subtle differences in V? gene usage. Finally, the absence of dual TCR T cells did not impact induced experimental autoimmune encephalomyelitis pathogenesis. Thus, despite more stringent allelic exclusion of TCR? relative to TCR?, bi-allelic TCR? expression can measurably impact thymocyte development and is necessary for maintaining normal ??/?? T cell proportions. PMID:26693713

  6. Developing T cell cancer immunotherapy in the dog with lymphoma.

    PubMed

    O'Connor, Colleen M; Wilson-Robles, Heather

    2014-01-01

    Immunotherapy is not a new concept for veterinary medicine; however, adoptive T cell therapy is a new area of research in humans and canines alike. In humans, T cell therapy has been used against many different tumor histologies, including lymphoma, melanoma, and colon cancer. Although in dogs this approach has currently only been applied to lymphoma, other tumor types are under investigation. There are many different strategies used to take advantage of cell-mediated antitumor properties of T cells. This review will discuss many of the current strategies used in both humans and canines in regards to adoptive T cell therapy. PMID:24936037

  7. Opportunities and challenges in development of phosphoantigens as V?9V?2 T cell agonists.

    PubMed

    Wiemer, David F; Wiemer, Andrew J

    2014-06-01

    In contrast to T cells that express the more prevalent ?? T cell receptor and respond to peptide antigens, T cells that express the V?9V?2 T cell receptor detect and respond to non-peptide phosphorous-containing small molecules known as phosphoantigens. Because ?? T cells are early responders to infections and malignancies, it has been suggested that stimulation of their activity with small molecule phosphoantigen drugs may hold promise for therapeutic interventions. Recent studies have greatly advanced our knowledge of phosphoantigens as well as their cellular receptors. At the same time, clinical trials of phosphoantigens have suggested that development of these V?9V?2 T cell agonists has met unexpected challenges. In this commentary, we summarize the biology that underlies phosphoantigen activity and discuss the structural features of synthetic phosphoantigens that affect both their ability to stimulate V?9V?2 T cells and their potential as therapeutic agents. PMID:24680696

  8. Regulation of early T cell development by the PHD finger of histone lysine methyltransferase ASH1

    SciTech Connect

    Tanaka, Yujiro Nakayama, Yasuhiro; Taniguchi, Masaru; Kioussis, Dimitris

    2008-01-18

    We have previously isolated a mammalian homologue of Drosophila discsabsent, small, orhomeotic-1 (ash1) from the murine thymus, and recently shown that its SET domain methylates histone H3 lysine 36 (K36). Expression of ASH1 has been reported to be increased in NOD thymocytes in a BDC2.5 clonotype background, but its function in T cell development has remained elusive. Here we report that the ash1 gene is expressed at high levels in thymocytes of mice deficient for rag1 or tcra genes. ASH1 proteins are present at peri-nuclei and as nuclear speckles in thymocytes. Some of the nuclear ASH1 co-localize with RAG2. Expression of the evolutionarily conserved PHD finger of ASH1 impairs T cell development at the DP stage, and causes increased transcription from the HoxA9 promoter in vitro. Moreover, the C-terminal part of ASH1 interacts with HDAC1 repression complexes, suggesting that the PHD finger of ASH1 may be involved in down-regulation of genes for normal development of {alpha}{beta} T cells.

  9. Innate PLZF+CD4+ ?? T cells develop and expand in the absence of Itk.

    PubMed

    Prince, Amanda L; Watkin, Levi B; Yin, Catherine C; Selin, Liisa K; Kang, Joonsoo; Schwartzberg, Pamela L; Berg, Leslie J

    2014-07-15

    T cell development in the thymus produces multiple lineages of cells, including innate T cells. Studies in mice harboring alterations in TCR signaling proteins or transcriptional regulators have revealed an expanded population of CD4(+) innate T cells in the thymus that produce IL-4 and express the transcription factor promyelocytic leukemia zinc finger (PLZF). In these mice, IL-4 produced by the CD4(+)PLZF(+) T cell population leads to the conversion of conventional CD8(+) thymocytes into innate CD8(+) T cells resembling memory T cells expressing eomesodermin. The expression of PLZF, the signature invariant NKT cell transcription factor, in these innate CD4(+) T cells suggests that they might be a subset of ?? or ?? TCR(+) NKT cells or mucosal-associated invariant T (MAIT) cells. To address these possibilities, we characterized the CD4(+)PLZF(+) innate T cells in itk(-/-) mice. We show that itk(-/-) innate PLZF(+)CD4(+) T cells are not CD1d-dependent NKT cells, MR1-dependent MAIT cells, or ?? T cells. Furthermore, although the itk(-/-) innate PLZF(+)CD4(+) T cells express ?? TCRs, neither ?2-microglobulin-dependent MHC class I nor any MHC class II molecules are required for their development. In contrast to invariant NKT cells and MAIT cells, this population has a highly diverse TCR?-chain repertoire. Analysis of peripheral tissues indicates that itk(-/-) innate PLZF(+)CD4(+) T cells preferentially home to spleen and mesenteric lymph nodes owing to increased expression of gut-homing receptors, and that their expansion is regulated by commensal gut flora. These data support the conclusion that itk(-/-) innate PLZF(+)CD4(+) T cells are a novel subset of innate T cells. PMID:24928994

  10. The Tec kinases Itk and Rlk regulate conventional versus innate T-cell development

    PubMed Central

    Prince, Amanda L.; Yin, Catherine C.; Enos, Megan E.; Felices, Martin; Berg, Leslie J.

    2009-01-01

    Summary Tec family kinases are important components of antigen receptor signaling pathways in B cells, T cells, and mast cells. In T cells, three members of this family, Itk, Rlk, and Tec, are expressed. In the absence of Itk and Rlk, T-cell receptor signaling is impaired, with defects in mitogen-activated protein kinase activation, Ca2+ mobilization, and actin polymerization. During T-cell development in the thymus, no role has been found for these kinases in the CD4+ versus CD8+ T-cell lineage decision; however, several studies indicate that Itk and Rlk contribute to the signaling leading to positive and negative selection. In addition, we and others have recently described an important role for Itk and Rlk in the development of conventional as opposed to innate CD4+ and CD8+ T cells. Natural killer T and ?? T-cell populations are also altered in Itk- and Rlk/Itk-deficient mice. These findings strongly suggest that the strength of T-cell receptor signaling during development determines whether T cells mature into conventional versus innate lymphocyte lineages. This lineage decision is also influenced by signaling via SLAM (signaling lymphocytic activation molecule) family receptors. Here we discuss these two signaling pathways that each contribute to conventional versus innate T-cell lineage commitment. PMID:19290924

  11. Dysfunction of irradiated thymus for the development of helper T cells

    SciTech Connect

    Amagai, T.; Kina, T.; Hirokawa, K.; Nishikawa, S.; Imanishi, J.; Katsura, Y.

    1987-07-15

    The development of cytotoxic T cells and helper T cells in an intact or irradiated thymus was investigated. C57BL/6 (H-2b, Thy-1.2) mice were whole body-irradiated, or were irradiated with shielding over either the thymus or right leg and tail, and were transferred with 1.5 X 10(7) bone marrow cells from B10.Thy-1.1 mice (H-2b, Thy-1.1). At various days after reconstitution, thymus cells from the recipient mice were harvested and a peanut agglutinin low-binding population was isolated. This population was further treated with anti-Thy-1.2 plus complement to remove host-derived cells and was assayed for the frequency of cytotoxic T cell precursors (CTLp) and for the activity of helper T cells (Th). In the thymus of thymus-shielded and irradiated mice, Th activity reached normal control level by day 25, whereas CTLp frequency remained at a very low level during these days. In the thymus of whole body-irradiated mice, generation of CTLp was highly accelerated while that of Th was retarded, the period required for reconstitution being 25 days and more than 42 days for CTLp and Th, respectively. Preferential development of CTLp was also seen in right leg- and tail-shielded (L-T-shielded) and irradiated recipients. Histological observation indicated that Ia+ nonlymphoid cells were well preserved in the thymus of thymus-shielded and irradiated recipients, whereas in L-T-shielded and irradiated recipients, such cells in the medulla were markedly reduced in number. These results suggest strongly that the generation of Th but not CTLp is dependent on radiosensitive thymic component(s), and that such components may represent Ia+ cells themselves in the medulla or some microenvironment related to Ia+ cells.

  12. Influence of time and number of antigen encounters on memory CD8 T cell development.

    PubMed

    Martin, Matthew D; Badovinac, Vladimir P

    2014-08-01

    CD8 T cells are an important part of the adaptive immune system providing protection against intracellular bacteria, viruses, and protozoa. After infection and/or vaccination, increased numbers of antigen-specific CD8 T cells remain as a memory population that is capable of responding and providing enhanced protection during reinfection. Experimental studies indicate that while memory CD8 T cells can be maintained for great lengths of time, their properties change with time after infection and/or vaccination. However, the full scope of these changes and what effects they have on memory CD8 T cell function remain unknown. In addition, memory CD8 T cells can encounter antigen multiple times through either reinfection or prime-boost vaccine strategies designed to increase numbers of protective memory CD8 T cells. Importantly, recent studies suggest that memory CD8 T cell development following infection and/or vaccination is influenced by the number of times they have encountered cognate antigen. Since protection offered by memory CD8 T cells in response to infection depends on both the numbers and quality (functional characteristics) at the time of pathogen re-encounter, a thorough understanding of how time and antigen stimulation history impacts memory CD8 T cell properties is critical for the design of vaccines aimed at establishing populations of long-lived, protective memory CD8 T cells. PMID:24825776

  13. Comparison of stress-induced PRINS gene expression in normal human keratinocytes and HaCaT cells.

    PubMed

    Bari, Lilla; Bacsa, Sarolta; Sonkoly, Eniko; Bata-Csörgo, Zsuzsanna; Kemény, Lajos; Dobozy, Attila; Széll, Márta

    2011-12-01

    Psoriasis is a chronic inflammatory skin disease that affects approximately 2-4% of the population. We recently described a novel non-coding RNA, psoriasis susceptibility related RNA gene induced by stress (PRINS), that was overexpressed in non-lesional psoriatic epidermis, and its expression was induced by various stress factors such as serum starvation, contact inhibition, ultraviolet (UV)-B irradiation, viral infection and translational inhibition in HaCaT cells. In the present work we set out to compare the stress and microbial agent-induced PRINS expression in normal human keratinocytes (NHKs) and HaCaT cells. Since nuclear factor-?B (NF-?B) is involved in the cellular stress response, we sought to explore whether there is a connection between the NF-?B and PRINS-mediated signal transduction pathways in NHKs and HaCaT cells. We found that the PRINS expression responded differentially to various stress signals and microbial agents in HaCaT cells and in NHKs: after translational inhibition and UV-B treatment, similar induction of PRINS expression occurred with different time courses while after microbial agent treatment, the PRINS expression was significantly induced in HaCaT cells, whereas we could not detect similar changes in NHKs. To explore whether the known NF-?B abnormalities in HaCaT cells could be related to this differential PRINS expression, we silenced the PRINS gene expression with small interfering RNA (siRNA) in both HaCaT cells and in NHKs and monitored NF-?B signal transduction after lipopolysaccharide (LPS) treatment. Silencing of PRINS had no effect on LPS-induced NF-?B activity either in HaCaT cells or in NHKs. Our results indicate that PRINS probably affects keratinocytes functions independently of NF-?B signalling. PMID:21750967

  14. CHARACTERIZATION OF NORMAL HUMAN LUNG LYMPHOCYTES AND INTERLEUKIN-2-INDUCED LUNG T CELL LINES

    EPA Science Inventory

    Lymphocytes from the lower respiratory tract were obtained by bronchoalveolar lavage of healthy, non-smoking individuals. arious monoclonal antibodies characterizing activated T cells, helper-inducer and suppressor-inducer T cell subsets, and naive versus memory cells were used t...

  15. 200 Million Thymocytes and I: A Beginner's Survival Guide to T Cell Development.

    PubMed

    Vacchio, Melanie S; Ciucci, Thomas; Bosselut, Rémy

    2016-01-01

    T lymphocytes (T cells) are essential for proper adaptive immune responses. They perform a variety of functions in defenses against pathogens, and notably control, positively or negatively, other cells involved in immune responses. T cells develop in the thymus from bone marrow-derived precursors. These precursors (thymocytes) proliferate, rearrange the genes encoding subunits of the T cell antigen receptor, which endow them with their unique antigen specificity, and undergo various degrees of pre-programming for their functions in immune responses. Thus, analyzing T cell development in the thymus is essential for understanding their functions in immune responses. In addition, the thymus constitutes an attractive experimental model to analyze mechanisms of cell proliferation, differentiation and survival, all of which are involved in thymocyte development. This chapter presents a quick overview of the key events characterizing intrathymic T cell development, as an introduction for readers entering this field of study. PMID:26294394

  16. Development of a Sendai virus vector-based AIDS vaccine inducing T cell responses.

    PubMed

    Seki, Sayuri; Matano, Tetsuro

    2016-01-01

    Virus-specific CD8(+) T-cell responses play a major role in the control of HIV replication, and induction of HIV-specific T-cell responses is an important strategy for AIDS vaccine development. Optimization of the delivery system and immunogen would be the key for the development of an effective T cell-based AIDS vaccine. Heterologous prime-boost vaccine regimens using multiple viral vectors are a promising protocol for efficient induction of HIV-specific T-cell responses, and the development of a variety of potent viral vectors have been attempted. This review describes the current progress of the development of T cell-based AIDS vaccines using viral vectors, focusing on Sendai virus vectors, whose phase I clinical trials have been performed. PMID:26512881

  17. A role for CD44 in T cell development and function during direct competition between CD44+ and CD44- cells.

    PubMed

    Graham, Victoria A; Marzo, Amanda L; Tough, David F

    2007-04-01

    The role of CD44 in T cell biology remains incompletely understood. Although studies using anti-CD44 antibodies have implicated this cell adhesion molecule in a variety of important T cell processes, few T cell defects have been reported in CD44-deficient mice. We have assessed the requirement for CD44 in T cell development and mature T cell function by analyzing mice in which CD44(-/-) and WT cells were produced simultaneously. In mixed (CD44(-/-) + CD44(+/+)) bone marrow chimeras, production of CD44(-/-) T cells was shown to be reduced compared to WT cells due to inefficient intrathymic development. In addition, mature CD44(-/-) CD8(+) T cells generated a substantially lower response than WT T cells after infection of mice with lymphocytic choriomeningitis virus, with the reduction in response apparent in both lymphoid and non-lymphoid tissues. Overall, these results demonstrate a poor capacity of CD44(-/-) T lineage cells to compete with WT cells at multiple levels, implicating CD44 in normal T cell function. PMID:17330818

  18. IL-6 trans-signaling-dependent rapid development of cytotoxic CD8+ T cell function.

    PubMed

    Böttcher, Jan P; Schanz, Oliver; Garbers, Christoph; Zaremba, Anne; Hegenbarth, Silke; Kurts, Christian; Beyer, Marc; Schultze, Joachim L; Kastenmüller, Wolfgang; Rose-John, Stefan; Knolle, Percy A

    2014-09-11

    Immune control of infections with viruses or intracellular bacteria relies on cytotoxic CD8(+) T cells that use granzyme B (GzmB) for elimination of infected cells. During inflammation, mature antigen-presenting dendritic cells instruct naive T cells within lymphoid organs to develop into effector T cells. Here, we report a mechanistically distinct and more rapid process of effector T cell development occurring within 18 hr. Such rapid acquisition of effector T cell function occurred through cross-presenting liver sinusoidal endothelial cells (LSECs) in the absence of innate immune stimulation and known costimulatory signaling. Rather, interleukin-6 (IL-6) trans-signaling was required and sufficient for rapid induction of GzmB expression in CD8(+) T cells. Such LSEC-stimulated GzmB-expressing CD8(+) T cells further responded to inflammatory cytokines, eliciting increased and protracted effector functions. Our findings identify a role for IL-6 trans-signaling in rapid generation of effector function in CD8(+) T cells that may be beneficial for vaccination strategies. PMID:25199826

  19. CD28 in thymocyte development and peripheral T cell activation in mice exposed to suspended particulate matter

    SciTech Connect

    Drela, Nadzieja . E-mail: ndrela@biol.uw.edu.pl; Zesko, Izabela; Jakubowska, Martyna; Biernacka, Marzena

    2006-09-01

    The CD28:B7 signaling pathway is very important for the activity of mature peripheral T lymphocytes and thymocyte development. The proper development of thymocytes into mature single positive CD4{sup +}and CD8{sup +} T cells is crucial for almost all immune functions. In naturally occurring conditions, T cells maturation in the thymus is influenced by environmental agents. The expression of CD28 and the distribution of CD28{sup low/high} thymocytes have been examined at various stages of thymocyte development in BALB/c mice exposed to air-suspended particulate matter (ASM). Acute exposure to ASM resulted in the decrease of CD28 expression in the total thymocyte population. The increase of the percentage of CD28{sup low} and the decrease of CD28{sup high} thymocytes were observed, which may account for the acceleration of thymocyte development under the conditions of elevated risk resulting from the exposure of animals to environmental xenobiotics. ASM exposure resulted in the increase of the level of proliferation of lymph node T cells induced by anti-CD3 and anti-CD28 monoclonal antibodies activation despite normal expression of CD28 molecule. In contrast, the level of proliferation of spleen T cells was lowered or normal dependently of the concentration of stimuli used for activation. Results of these studies demonstrate that acute exposure of mice to ASM can result in the progression of two contrasting processes in the immune system: upregulation of thymocyte development, which contributes to the maintenance of peripheral T cell pool, and over-activation of lymph node lymphocytes, which may lead to uncontrolled immunostimulation.

  20. IL-17-producing ??T cells are regulated by estrogen during development of experimental arthritis.

    PubMed

    Andersson, Annica; Grahnemo, Louise; Engdahl, Cecilia; Stubelius, Alexandra; Lagerquist, Marie K; Carlsten, Hans; Islander, Ulrika

    2015-12-01

    Interleukin-17 (IL-17) drives inflammation and destruction of joints in rheumatoid arthritis (RA). The female sex hormone 17?-estradiol (E2) inhibits experimental arthritis. ??T cells are significant producers of IL-17, thus the aim of this study was to investigate if E2 influenced IL-17(+) ??T cells during arthritis development using a variety of experimental RA models: collagen-induced arthritis (CIA); antigen-induced arthritis (AIA); and collagen antibody-induced arthritis (CAIA). We demonstrate that E2 treatment decreases IL-17(+) ??T cell number in joints, but increases IL-17(+) ??T cells in draining lymph nodes, suggesting an E2-mediated prevention of IL-17(+) ??T cell migration from lymph nodes to joints, in concert with our recently reported effects of E2 on Th17 cells (Andersson et al., 2015). E2 did neither influence the general ??T cell population nor IFN?(+) ??T cells, implying a selective regulation of IL-17-producing cells. In conclusion, this study contributes to the understanding of estrogen's role in autoimmune disease. PMID:26423309

  1. Unexpected Regulatory Role of CCR9 in Regulatory T Cell Development

    PubMed Central

    Evans-Marin, Heather L.; Cao, Anthony T.; Yao, Suxia; Chen, Feidi; He, Chong; Liu, Han; Wu, Wei; Gonzalez, Maria G.; Dann, Sara M.; Cong, Yingzi

    2015-01-01

    T cells reactive to microbiota regulate the pathogenesis of inflammatory bowel disease (IBD). As T cell trafficking to intestines is regulated through interactions between highly specific chemokine-chemokine receptors, efforts have been made to develop intestine-specific immunosuppression based on blocking these key processes. CCR9, a gut-trophic chemokine receptor expressed by lymphocytes and dendritic cells, has been implicated in the regulation of IBD through mediating recruitment of T cells to inflamed sites. However, the role of CCR9 in inducing and sustaining inflammation in the context of IBD is poorly understood. In this study, we demonstrate that CCR9 deficiency in effector T cells and Tregs does not affect the development of colitis in a microbiota antigen-specific, T cell-mediated model. However, Treg cells express higher levels of CCR9 compared to those in effector T cells. Interestingly, CCR9 inhibits Treg cell development, in that CCR9-/- mice demonstrate a high level of Foxp3+ Tregs, and ligation of CCR9 by its ligand CCL25 inhibits Treg cell differentiation in vitro. Collectively, our data indicate that in addition to acting as a gut-homing molecule, CCR9 signaling shapes immune responses by inhibiting Treg cell development. PMID:26230654

  2. Kinetics of mature T-cell development in the thymus

    SciTech Connect

    Egerton, M.; Scollay, R.; Shortman, K. )

    1990-04-01

    We have reexamined the balance between cell birth, cell maturation, and cell death in the thymus by labeling dividing thymocytes and their progeny in vivo with (3H)-thymidine, isolating clearly defined subpopulations by fluorescence-activated cell sorting, and determining the distribution of label by autoradiography. When mature thymocytes were precisely defined (as CD4+CD8- CD3+ or CD4-CD8+ CD3+) and separated from immature single positives (CD4+CD8- CD3- and CD4-CD8+ CD3-), a lag was observed in the rate of entry of (3H)thymidine into mature cells. Thus, many of the mature thymocytes appear to derive from a small nondividing cortical thymocyte pool, rather than originating directly from the earliest dividing CD4+CD8+ blasts. There was little evidence for cell division during or after mature thymocyte formation, suggesting a one-for-one differentiation from cortical cells rather than selective clonal expansion. The rate of production of mature single positive thymocytes agreed closely with estimates of the rate of export of mature T cells from the thymus and was only 3% of the rate of production of double-positive cortical thymocytes. This was compatible with a stringent selection process and extensive intrathymic cell death and suggested that no extensive negative selection occurred after the mature cells were formed.

  3. Influence of Ganoderma lucidum (Curt.: Fr.) P. Karst. on T-cell-mediated immunity in normal and immunosuppressed mice line CBA/Ca.

    PubMed

    Nizhenkovska, Iryna V; Pidchenko, Vitalii T; Bychkova, Nina G; Bisko, Nina A; Rodnichenko, Angela Y; Kozyko, Natalya O

    2015-09-01

    The article presents the results of the investigation of the effect of biomass powder of the fungus Ganoderma lucidum on T-cell-mediated immunity in normal and immunosuppressed mice CBA/Ca. Delayed-type hypersensitivity assay was used. Experimental immunodeficiency was established with intraperitoneal injection of the immunosuppressant cyclophosphamide at a single dose of 150 mg/kg on the first day of the experiment. Results of the study show that the administration of biomass powder of Ganoderma lucidum in a dose of 0.5 mg/kg orally for 10 days increases the delayed-type hypersensitivity response in normal mice CBA/Ca. Administration of 0.5 mg/kg of biomass powder of the fungus Ganoderma lucidum for 10 days blocked the development of the T-cell-mediated immunosuppression, induced by administration of cyclophosphamide and restored the delayed-type hypersensitivity response in immunosuppressed mice. Key words: fungus Ganoderma lucidum cyclophosphamide immunodeficiency T-cell-mediated immunity delayed-type hypersensitivity. PMID:26459128

  4. Essential roles for Cav?2 and Cav1 channels in thymocyte development and T cell homeostasis.

    PubMed

    Jha, Archana; Singh, Ashish K; Weissgerber, Petra; Freichel, Marc; Flockerzi, Veit; Flavell, Richard A; Jha, Mithilesh K

    2015-01-01

    Calcium ions (Ca(2+)) are important in numerous signal transduction processes, including the development and differentiation of T cells in the thymus. We report that thymocytes have multiple types of pore-forming ? subunits and regulatory ? subunits that constitute voltage-gated Ca(2+) (Cav) channels. In mice, T cell-specific deletion of the gene encoding the ?2 regulatory subunit of Cav channels (Cacnb2) reduced the abundances of the channels Cav1.2 and Cav1.3 (both of which contain pore-forming ?1 subunits) and impaired T cell development, which led to a substantial decrease in the numbers of thymocytes and peripheral T cells. Similar to the effect of Cacnb2 deficiency, pharmacological blockade of pore-forming Cav1? subunits reduced the sustained Ca(2+) influx in thymocytes upon stimulation of the T cell receptor, decreased the abundance of the transcription factor NFATc3, inhibited the proliferation of thymocytes in vitro, and led to lymphopenia in mice. Together, our data suggest that Cav1 channels are conduits for the sustained Ca(2+) influx that is required for the development of T cells. PMID:26486172

  5. Genetic Requirements for the Development and Differentiation of Interleukin-17–Producing ?? T Cells

    PubMed Central

    Hayes, Sandra M.; Laird, Renee M.

    2012-01-01

    Most effector T cells are generated in the periphery following an encounter with a foreign antigen and exposure to soluble and membrane-bound mediators. There are, however, some T cell subsets, such as ?? T cells and natural killer T cells, that acquire their effector potential in the thymus before their emigration to the periphery. This developmental preprogramming enables these cells to differentiate rapidly into cytokine-producing effectors during the host immune response. This review focuses on murine interleukin (IL)-17–producing ?? T (??-17) cells, which have been shown, through their early production of IL-17, to have a critical role in multiple infectious and autoimmune diseases. Specifically, we discuss what is currently known about the genetic requirements for their generation and compare it with what is known about that of the more extensively studied IL-17–producing helper T (Th17) cells. Based on this comparison, we propose a model for murine ??-17 development and differentiation. PMID:22428856

  6. Characterization of In Vivo Dlg1 Deletion on T Cell Development and Function

    PubMed Central

    Tomassian, Tamar; McMahon, Kerrie-Ann; Humbert, Patrick O.; Silva, Oscar; Round, June L.; Takamiya, Kogo; Huganir, Richard L.

    2012-01-01

    Background The polarized reorganization of the T cell membrane and intracellular signaling molecules in response to T cell receptor (TCR) engagement has been implicated in the modulation of T cell development and effector responses. In siRNA-based studies Dlg1, a MAGUK scaffold protein and member of the Scribble polarity complex, has been shown to play a role in T cell polarity and TCR signal specificity, however the role of Dlg1 in T cell development and function in vivo remains unclear. Methodology/Principal Findings Here we present the combined data from three independently-derived dlg1-knockout mouse models; two germline deficient knockouts and one conditional knockout. While defects were not observed in T cell development, TCR-induced early phospho-signaling, actin-mediated events, or proliferation in any of the models, the acute knockdown of Dlg1 in Jurkat T cells diminished accumulation of actin at the IS. Further, while Th1-type cytokine production appeared unaffected in T cells derived from mice with a dlg1germline-deficiency, altered production of TCR-dependent Th1 and Th2-type cytokines was observed in T cells derived from mice with a conditional loss of dlg1 expression and T cells with acute Dlg1 suppression, suggesting a differential requirement for Dlg1 activity in signaling events leading to Th1 versus Th2 cytokine induction. The observed inconsistencies between these and other knockout models and siRNA strategies suggest that 1) compensatory upregulation of alternate gene(s) may be masking a role for dlg1 in controlling TCR-mediated events in dlg1 deficient mice and 2) the developmental stage during which dlg1 ablation begins may control the degree to which compensatory events occur. Conclusions/Significance These findings provide a potential explanation for the discrepancies observed in various studies using different dlg1-deficient T cell models and underscore the importance of acute dlg1 ablation to avoid the upregulation of compensatory mechanisms for future functional studies of the Dlg1 protein. PMID:23028902

  7. A77 1726, the active metabolite of leflunomide, attenuates lupus nephritis by promoting the development of regulatory T cells and inhibiting IL-17-producing double negative T cells.

    PubMed

    Qiao, Guilin; Yang, Lifen; Li, Zhenping; Williams, James W; Zhang, Jian

    2015-04-01

    Lupus nephritis (LN) is a challenging problem that affects 50% of patients with systemic lupus erythematosus (SLE) without effective therapy. Here, we report that A77 1726, the active metabolite of leflunomide, effectively inhibits development of LN and attenuates the generalized autoimmune features. A77 1726 suppresses the expansion of double negative (DN) T cells, and inhibits T and B cell activation. Intriguingly, A77 1726 treatment significantly increases CD4(+)Foxp3(+) regulatory T cells but suppresses potential "pathogenic" IL-17-producing DN T cells in lymph nodes. In vitro experiment shows that A77 1726 potentiates the conversion of naive CD4(+)CD25(-) T cells into CD4(+)CD25(+)Foxp3(+) inducible regulatory T cells (iTregs) by inhibiting Akt. Taken together, our data indicate that the therapeutic effects of A77 1726 in murine LN are mediated, at least in part, by augmenting iTregs which suppress pathogenic IL-17-producing DN T cells through an Akt-dependent mechanism. PMID:25638413

  8. Thymic Stromal-Cell Abnormalities and Dysregulated T-Cell Development in IL-2-Deficient Mice

    PubMed Central

    Reya, Tannishtha; Bassiri, Hamid; Biancaniello, Renée

    1998-01-01

    The role that interleukin-2 (IL-2) plays in T-cell development is not known. To address this issue, we have investigated the nature of the abnormal thymic development and autoimmune disorders that occurs in IL-2-deficient (IL-2–/–) mice. After 4 to 5 weeks of birth, IL-2–/– mice progressively develop a thymic disorder resulting in the disruption of thymocyte maturation. This disorder is characterized by a dramatic reduction in cellularity, the selective loss of immature CD4-8- (double negative; DN) and CD4+8+ (double positive; DP) thymocytes and defects in the thymic stromal-cell compartment. Immunohistochemical staining of sections of thymuses from specific pathogen-free and germ-free IL-2–/– mice of various ages showed a progressive ,loss of cortical epithelial cells, MHC class II-expressing cells, monocytes, and macrophages. Reduced numbers of macrophages were apparent as early as week after birth. Since IL-2–/– thymocyte progenitor populations could mature normally on transfer into a normal thymus, the thymic defect in IL-2–/– mice appears to be due to abnormalities among thymic stromal cells. These results underscore the role of IL-2 in maintaining functional microenvironments that are necessary to support thymocyte growth, development, and selection. PMID:9814585

  9. CD5 instructs extrathymic regulatory T cell development in response to self and tolerizing antigens.

    PubMed

    Henderson, Jacob G; Opejin, Adeleye; Jones, Andrew; Gross, Cindy; Hawiger, Daniel

    2015-03-17

    Self-reactive T cells can escape thymic deletion and therefore some of these potentially autoaggressive T cells need to convert into regulatory T (Treg) cells to help control responses against self. However, it remains unknown how peripheral self-reactive T cells are specifically instructed to become Treg cells. We report that CD5, whose expression is upregulated in T cells by self and tolerizing antigens in the thymus and periphery, governed extrathymic Treg cell development. CD5 modified effector cell-differentiating signals that inhibit Treg cell induction. Treg cell conversion of Cd5(-/-) and CD5(lo) T cells was inhibited by even small amounts of interleukin-4 (IL-4), IL-6, and interferon-? (IFN-?) produced by bystander lymphocytes, while CD5(hi) T cells resisted this inhibition of Treg cell induction. Our findings further revealed that CD5 promoted Treg cell induction by blocking mechanistic target of rapamycin (mTOR) activation. Therefore CD5 instructs extrathymic Treg cell development in response to self and tolerizing antigens. PMID:25786177

  10. Notch Signaling in T-Cell Development and T-ALL

    PubMed Central

    Li, Xiaoyu; von Boehmer, Harald

    2011-01-01

    The Notch signaling pathway is an evolutionarily conserved cell signaling system present in most multicellular organisms, as it controls cell fate specification by regulating cell proliferation, differentiation, apoptosis, and survival. Regulation of the Notch signaling pathway can be achieved at multiple levels. Notch proteins are involved in lineage fate decisions in a variety of tissues in various species. Notch is essential for T lineage cell differentiation including T versus B and ?? versus ?? lineage specification. In this paper, we discuss Notch signaling in normal T-cell maturation and differentiation as well as in T-cell acute lymphoblastic lymphoma/leukemia. PMID:22111016

  11. The common gamma chain cytokines interleukin (IL)-2 and IL-7 indirectly modulate blood fluke development via effects on CD4+ T cells.

    PubMed

    Blank, Rebecca B; Lamb, Erika W; Tocheva, Anna S; Crow, Emily T; Lim, K C; McKerrow, James H; Davies, Stephen J

    2006-12-01

    The human pathogen Schistosoma mansoni exhibits a highly evolved and intricate relationship with its host, evading immune destruction while co-opting CD4(+) T cell-driven mechanisms to facilitate parasite development and egg excretion. Because the common gamma ( gamma (c)) chain cytokine interleukin (IL)-7 is also implicated in modulating schistosome development, we investigated whether this effect is mediated indirectly through the essential role that IL-7 plays in CD4(+) T cell growth and survival. We demonstrate that attenuated schistosome development in the absence of IL-7 results from dysregulated T cell homeostasis and not from disruption of direct interactions between schistosomes and IL-7. We also identify an indirect role that another gamma (c) chain cytokine plays in schistosome development, demonstrating that IL-2 expression by CD4(+) T cells is essential for normal parasite development. Thus, cytokines critical for CD4(+) T cell survival and function can mediate indirect but potent effects on developing schistosomes and underscore the importance of CD4(+) T cells in facilitating schistosome development. PMID:17083048

  12. PD-1 and Tim-3 pathways are associated with regulatory CD8+ T-cell function in decidua and maintenance of normal pregnancy

    PubMed Central

    Wang, S-C; Li, Y-H; Piao, H-L; Hong, X-W; Zhang, D; Xu, Y-Y; Tao, Y; Wang, Y; Yuan, M-M; Li, D-J; Du, M-R

    2015-01-01

    CD8+ T cells are critical in the balance between fetal tolerance and antiviral immunity. T-cell immunoglobulin mucin-3 (Tim-3) and programmed cell death-1 (PD-1) are important negative immune regulatory molecules involved in viral persistence and tumor metastasis. Here, we demonstrate that Tim-3+PD-1+CD8+ T cells from decidua greatly outnumbered those from peripheral blood during human early pregnancy. Co-culture of trophoblasts with CD8+ T cells upregulated PD-1+ and/or Tim-3+ immune cells. Furthermore, the population of CD8+ T cells co-expressing PD-1 and Tim-3 was enriched within the intermediate memory subset in decidua. This population exhibited high proliferative activity and Th2-type cytokine producing capacity. Blockade of Tim-3 and PD-1 resulted in decreased in vitro proliferation and Th2-type cytokine production while increased trophoblast killing and IFN-? producing capacities of CD8+ T cells. Pregnant CBA/J females challenged with Tim-3 and/or PD-1 blocking antibodies were more susceptible to fetal loss, which was associated with CD8+ T-cell dysfunction. Importantly, the number and function of Tim-3+PD-1+CD8+ T cells in decidua were significantly impaired in miscarriage. These findings underline the important roles of Tim-3 and PD-1 pathways in regulating decidual CD8+ T-cell function and maintaining normal pregnancy. PMID:25950468

  13. Kinetics of T-cell receptor-dependent antigen recognition determined in vivo by multi-spectral normalized epifluorescence laser scanning

    NASA Astrophysics Data System (ADS)

    Favicchio, Rosy; Zacharakis, Giannis; Oikonomaki, Katerina; Zacharopoulos, Athanasios; Mamalaki, Clio; Ripoll, Jorge

    2012-07-01

    Detection of multiple fluorophores in conditions of low signal represents a limiting factor for the application of in vivo optical imaging techniques in immunology where fluorescent labels report for different functional characteristics. A noninvasive in vivo Multi-Spectral Normalized Epifluorescence Laser scanning (M-SNELS) method was developed for the simultaneous and quantitative detection of multiple fluorophores in low signal to noise ratios and used to follow T-cell activation and clonal expansion. Colocalized DsRed- and GFP-labeled T cells were followed in tandem during the mounting of an immune response. Spectral unmixing was used to distinguish the overlapping fluorescent emissions representative of the two distinct cell populations and longitudinal data reported the discrete pattern of antigen-driven proliferation. Retrieved values were validated both in vitro and in vivo with flow cytometry and significant correlation between all methodologies was achieved. Noninvasive M-SNELS successfully quantified two colocalized fluorescent populations and provides a valid alternative imaging approach to traditional invasive methods for detecting T cell dynamics.

  14. Type 1 cytokines polarize thymocytes during T cell development in adult thymus organ cultures.

    PubMed

    Whalen, Barbara J; Marounek, Jan; Mordes, John P; Rossini, Aldo A; Greiner, Dale L

    2003-02-01

    Peripheral T cells can be polarized towards type 1 or type 2 cytokine immune responses during TCR engagement. Because T cell selection by peptide plus self-MHC in the thymus requires TCR engagement, we hypothesized that type 1 cytokines may polarize developing T cells. We cultured thymi from BBDR rats in adult thymus organ cultures (ATOC) under type 1 cytokine conditions in the absence of exogenous antigen. Type 1 cytokine-conditioned ATOC generated cells that spontaneously secreted high levels of IFNgamma, but not IL-4. A second exposure to type 1 cytokines further increased IFNgamma secretion by these cells, most of which were blasts that expressed the activation markers CD25, CD71, CD86, and CD134. Studies using blocking antibodies and pharmacological inhibitors suggested that both IL-18 and cognate TCR-MHC/ligand interactions were important for activation. Blocking anti-MHC class I plus anti-MHC class II antibodies, neutralizing anti-IL-18 antibody, and the p38 MAP-kinase inhibitor SB203580 each reduced IFNgamma production by approximately 75-80%. Cyclosporin A, which prevents TCR signaling, inhibited IFNgamma production by approximately 50%. These data demonstrate that exposure to type 1 cytokines during intrathymic development can polarize differentiating T cells, and suggest a mechanism by which intrathymic exposure to type 1 cytokines may modulate T cell development. PMID:12604310

  15. RET/GFR? Signals Are Dispensable for Thymic T Cell Development In Vivo

    PubMed Central

    Almeida, Afonso Rocha Martins; Arroz-Madeira, Sílvia; Fonseca-Pereira, Diogo; Ribeiro, Hélder; Lasrado, Reena; Pachnis, Vassilis; Veiga-Fernandes, Henrique

    2012-01-01

    Identification of thymocyte regulators is a central issue in T cell biology. Interestingly, growing evidence indicates that common key molecules control neuronal and immune cell functions. The neurotrophic factor receptor RET mediates critical functions in foetal hematopoietic subsets, thus raising the possibility that RET-related molecules may also control T cell development. We show that Ret, Gfra1 and Gfra2 are abundantly expressed by foetal and adult immature DN thymocytes. Despite the developmentally regulated expression of these genes, analysis of foetal thymi from Gfra1, Gfra2 or Ret deficient embryos revealed that these molecules are dispensable for foetal T cell development. Furthermore, analysis of RET gain of function and Ret conditional knockout mice showed that RET is also unnecessary for adult thymopoiesis. Finally, competitive thymic reconstitution assays indicated that Ret deficient thymocytes maintained their differentiation fitness even in stringent developmental conditions. Thus, our data demonstrate that RET/GFR? signals are dispensable for thymic T cell development in vivo, indicating that pharmacological targeting of RET signalling in tumours is not likely to result in T cell production failure. PMID:23300832

  16. Bystander chronic infection negatively impacts development of CD8+ T cell memory

    PubMed Central

    Stelekati, Erietta; Shin, Haina; Doering, Travis A.; Dolfi, Douglas V.; Ziegler, Carly G.; Beiting, Daniel P.; Dawson, Lucas; Liboon, Jennifer; Wolski, David; Ali, Mohammed-Alkhatim A.; Katsikis, Peter D.; Shen, Hao; Roos, David S.; Haining, W. Nicholas; Lauer, Georg M.; Wherry, E. John

    2014-01-01

    Summary Epidemiological evidence suggests that chronic infections impair immune responses to unrelated pathogens and vaccines. The underlying mechanisms, however, are unclear and distinguishing effects on priming versus development of immunological memory has been challenging. We investigated whether bystander chronic infections impact differentiation of memory CD8+ T cells, the hallmark of protective immunity against intracellular pathogens. Chronic bystander infections impaired development of memory CD8+ T cells in several mouse models and humans. These effects were independent of initial priming and were associated with chronic inflammatory signatures. Chronic inflammation negatively impacted the number of bystander CD8+ T cells and their memory development. Distinct underlying mechanisms of altered survival and differentiation were revealed with the latter regulated by the transcription factors T-bet and Blimp-1. Thus, exposure to prolonged bystander inflammation impairs the effector to memory transition. These data have relevance for immunity and vaccination during persisting infections and chronic inflammation. PMID:24837104

  17. Altered T Cell Memory and Effector Cell Development in Chronic Lymphatic Filarial Infection That Is Independent of Persistent Parasite Antigen

    PubMed Central

    Steel, Cathy; Nutman, Thomas B.

    2011-01-01

    Chronic lymphatic filarial (LF) infection is associated with suppression of parasite-specific T cell responses that persist even following elimination of infection. While several mechanisms have been implicated in mediating this T cell specific downregulation, a role for alterations in the homeostasis of T effector and memory cell populations has not been explored. Using multiparameter flow cytometry, we investigated the role of persistent filarial infection on the maintenance of T cell memory in patients from the filarial-endemic Cook Islands. Compared to filarial-uninfected endemic normals (EN), microfilaria (mf) positive infected patients (Inf) had a reduced CD4 central memory (TCM) compartment. In addition, Inf patients tended to have more effector memory cells (TEM) and fewer effector cells (TEFF) than did ENs giving significantly smaller TEFF ? TEM ratios. These contracted TCM and TEFF populations were still evident in patients previously mf+ who had cleared their infection (CLInf). Moreover, the density of IL-7R?, necessary for T memory cell maintenance (but decreased in T effector cells), was significantly higher on memory cells of Inf and CLInf patients, although there was no evidence for decreased IL-7 or increased soluble IL7-R?, both possible mechanisms for signaling defects in memory cells. However, effector cells that were present in Inf and CLInf patients had lower percentages of HLA-DR suggesting impaired function. These changes in T cell populations appear to reflect chronicity of infection, as filarial-infected children, despite the presence of active infection, did not show alterations in the frequencies of these T cell phenotypes. These data indicate that filarial-infected patients have contracted TCM compartments and a defect in effector cell development, defects that persist even following clearance of infection. The fact that these global changes in memory and effector cell compartments do not yet occur in infected children makes early treatment of LF even more crucial. PMID:21559422

  18. Induction of T Cell Development In Vitro by Delta-Like (Dll)-Expressing Stromal Cells.

    PubMed

    Mohtashami, Mahmood; Zarin, Payam; Zúñiga-Pflücker, Juan Carlos

    2016-01-01

    Recreating the thymic microenvironment in vitro poses a great challenge to immunologists. Until recently, the only approach was to utilize the thymic tissue in its three-dimensional form and to transfer the hematopoietic progenitors into this tissue to generate de novo T cells. With the advent of OP9-DL cells (bone marrow-derived cells that are transduced to express Notch ligand, Delta-like), hematopoietic stem cells (HSC) could be induced to differentiate into T cells in culture for the first time outside of the thymic tissue on a monolayer. We, as well as others, asked whether the ability to support T cell development in vitro in a monolayer is unique to BM-derived OP9 cells, and showed that provision of Delta-like expression to thymic epithelial cells and fibroblasts also allowed for T cell development. This provides the opportunity to design an autologous coculture system where the supportive stromal and the hematopoietic components are both derived from the same individual, which has obvious clinical implications. In this chapter, we describe methods for establishing a primary murine dermal fibroblast cell population that is transduced to express Delta-like 4, and describe the conditions for its coculture with HSCs to support T cell lineage initiation and expansion, while comparing it to the now classic OP9-DL coculture. PMID:26294407

  19. IL-1 receptor antagonist-deficient mice develop autoimmune arthritis due to intrinsic activation of IL-17-producing CCR2+V?6+?? T cells

    PubMed Central

    Akitsu, Aoi; Ishigame, Harumichi; Kakuta, Shigeru; Chung, Soo-hyun; Ikeda, Satoshi; Shimizu, Kenji; Kubo, Sachiko; Liu, Yang; Umemura, Masayuki; Matsuzaki, Goro; Yoshikai, Yasunobu; Saijo, Shinobu; Iwakura, Yoichiro

    2015-01-01

    Interleukin-17 (IL-17)-producing ?? T (??17) cells have been implicated in inflammatory diseases, but the underlying pathogenic mechanisms remain unclear. Here, we show that both CD4+ and ??17 cells are required for the development of autoimmune arthritis in IL-1 receptor antagonist (IL-1Ra)-deficient mice. Specifically, activated CD4+ T cells direct ?? T-cell infiltration by inducing CCL2 expression in joints. Furthermore, IL-17 reporter mice reveal that the V?6+ subset of CCR2+ ?? T cells preferentially produces IL-17 in inflamed joints. Importantly, because IL-1Ra normally suppresses IL-1R expression on ?? T cells, IL-1Ra-deficient mice exhibit elevated IL-1R expression on V?6+ cells, which play a critical role in inducing them to produce IL-17. Our findings demonstrate a pathogenic mechanism in which adaptive and innate immunity induce an autoimmune disease in a coordinated manner. PMID:26108163

  20. IL-1 receptor antagonist-deficient mice develop autoimmune arthritis due to intrinsic activation of IL-17-producing CCR2(+)V?6(+)?? T cells.

    PubMed

    Akitsu, Aoi; Ishigame, Harumichi; Kakuta, Shigeru; Chung, Soo-Hyun; Ikeda, Satoshi; Shimizu, Kenji; Kubo, Sachiko; Liu, Yang; Umemura, Masayuki; Matsuzaki, Goro; Yoshikai, Yasunobu; Saijo, Shinobu; Iwakura, Yoichiro

    2015-01-01

    Interleukin-17 (IL-17)-producing ?? T (??17) cells have been implicated in inflammatory diseases, but the underlying pathogenic mechanisms remain unclear. Here, we show that both CD4(+) and ??17 cells are required for the development of autoimmune arthritis in IL-1 receptor antagonist (IL-1Ra)-deficient mice. Specifically, activated CD4(+) T cells direct ?? T-cell infiltration by inducing CCL2 expression in joints. Furthermore, IL-17 reporter mice reveal that the V?6(+) subset of CCR2(+) ?? T cells preferentially produces IL-17 in inflamed joints. Importantly, because IL-1Ra normally suppresses IL-1R expression on ?? T cells, IL-1Ra-deficient mice exhibit elevated IL-1R expression on V?6(+) cells, which play a critical role in inducing them to produce IL-17. Our findings demonstrate a pathogenic mechanism in which adaptive and innate immunity induce an autoimmune disease in a coordinated manner. PMID:26108163

  1. Repertoire Development and the Control of Cytotoxic/Effector Function in Human ?? T Cells

    PubMed Central

    Urban, Elizabeth M.; Chapoval, Andrei I.; Pauza, C. David

    2010-01-01

    T cells develop into two major populations distinguished by their T cell receptor (TCR) chains. Cells with the ?? TCR generally express CD4 or CD8 lineage markers and mostly fall into helper or cytotoxic/effector subsets. Cells expressing the alternate ?? TCR in humans generally do not express lineage markers, do not require MHC for antigen presentation, and recognize nonpeptidic antigens. We are interested in the dominant V?2V?2+ T cell subset in human peripheral blood and the control of effector function in this population. We review the literature on ?? T cell generation and repertoire selection, along with recent work on CD56 expression and defining a cytotoxic/effector lineage within the phosphoantigen-reactive V?2V?2 cells. A unique mechanism for MHC-independent repertoire selection is linked to the control of effector function that is vital to the role for ?? T cells in tumor surveillance. Better understanding of these mechanisms will improve our ability to exploit this population for tumor immunotherapy. PMID:20396597

  2. The effects of radio-frequency electromagnetic fields on T cell function during development

    PubMed Central

    Ohtani, Shin; Ushiyama, Akira; Maeda, Machiko; Ogasawara, Yuki; Wang, Jianqing; Kunugita, Naoki; Ishii, Kazuyuki

    2015-01-01

    With the widespread use of radio-frequency devices, it is increasingly important to understand the biological effects of the associated electromagnetic fields. Thus, we investigated the effects of radio-frequency electromagnetic fields (RF-EMF) on T cell responses during development due to the lack of science-based evidence for RF-EMF effects on developmental immune systems. Sprague Dawley (SD) rats were exposed to 2.14-GHz wideband code division multiple-access (W-CDMA) RF signals at a whole-body specific absorption rate (SAR) of 0.2 W/kg. Exposures were performed for a total of 9 weeks spanning in utero development, lactation and the juvenile period. Rats were continuously exposed to RF-EMF for 20 h/day, 7 days/week. Comparisons of control and exposed rats using flow cytometry revealed no changes in the numbers of CD4/CD8 T cells, activated T cells or regulatory T cells among peripheral blood cells, splenocytes and thymocytes. Expression levels of 16 genes that regulate the immunological Th1/Th2 paradigm were analyzed using real-time PCR in the spleen and thymus tissues of control and RF-EMF–exposed rats. Although only the Il5 gene was significantly regulated in spleen tissues, Il4, Il5 and Il23a genes were significantly upregulated in thymus tissues following exposure to RF-EMF. However, ELISAs showed no changes in serum IL-4 protein concentrations. These data indicate no adverse effects of long-term RF-EMF exposure on immune-like T cell populations, T cell activation, or Th1/Th2 balance in developing rats, although significant transcriptional effects were observed. PMID:25835473

  3. The effects of radio-frequency electromagnetic fields on T cell function during development.

    PubMed

    Ohtani, Shin; Ushiyama, Akira; Maeda, Machiko; Ogasawara, Yuki; Wang, Jianqing; Kunugita, Naoki; Ishii, Kazuyuki

    2015-05-01

    With the widespread use of radio-frequency devices, it is increasingly important to understand the biological effects of the associated electromagnetic fields. Thus, we investigated the effects of radio-frequency electromagnetic fields (RF-EMF) on T cell responses during development due to the lack of science-based evidence for RF-EMF effects on developmental immune systems. Sprague Dawley (SD) rats were exposed to 2.14-GHz wideband code division multiple-access (W-CDMA) RF signals at a whole-body specific absorption rate (SAR) of 0.2 W/kg. Exposures were performed for a total of 9 weeks spanning in utero development, lactation and the juvenile period. Rats were continuously exposed to RF-EMF for 20 h/day, 7 days/week. Comparisons of control and exposed rats using flow cytometry revealed no changes in the numbers of CD4/CD8 T cells, activated T cells or regulatory T cells among peripheral blood cells, splenocytes and thymocytes. Expression levels of 16 genes that regulate the immunological Th1/Th2 paradigm were analyzed using real-time PCR in the spleen and thymus tissues of control and RF-EMF-exposed rats. Although only the Il5 gene was significantly regulated in spleen tissues, Il4, Il5 and Il23a genes were significantly upregulated in thymus tissues following exposure to RF-EMF. However, ELISAs showed no changes in serum IL-4 protein concentrations. These data indicate no adverse effects of long-term RF-EMF exposure on immune-like T cell populations, T cell activation, or Th1/Th2 balance in developing rats, although significant transcriptional effects were observed. PMID:25835473

  4. Timely and spatially regulated maturation of B and T cell repertoire during human fetal development.

    PubMed

    Rechavi, Erez; Lev, Atar; Lee, Yu Nee; Simon, Amos J; Yinon, Yoav; Lipitz, Schlomo; Amariglio, Ninette; Weisz, Boaz; Notarangelo, Luigi D; Somech, Raz

    2015-02-25

    Insights into the ontogeny of the human fetal adaptive immune system are of great value for understanding immunocompetence of the developing fetus. However, to date, this has remained largely uncharted territory, in large part because blood samples from healthy, early gestation fetuses have been hard to come by. In a comprehensive study, we analyzed levels of T cell receptor excision circles (TRECs), signal-joint ? receptor excision circles (sjKRECs), and intron recombination signal sequence-K-deleting element (iRSS-Kde) rearrangement, and T and B lymphocyte repertoire clonality in human fetuses from 12 to 26 weeks of gestational age. Using next-generation sequencing, we analyzed the diversity and complexity of T cell receptor ? (TRB) and immunoglobulin heavy chain (IGH) repertoires in four fetuses at 12, 13, 22, and 26 weeks of gestation and in healthy full-term infants. We report the progressive increase of TREC, sjKREC, and iRSS-Kde levels over time and confirm that B cell development precedes T cell development in the human fetus. Temporally and spatially regulated maturation of B and T cell repertoire diversity and complexity during human fetal development was observed, including evidence that immunoglobulin somatic hypermutation and class switch recombination occur already during intrauterine life. Our results help define physiological levels of immunodeficiency in premature infants and may serve as a reference for future studies aimed at investigating the impact of intrauterine pathologies on fetal immune development and function. PMID:25717098

  5. OLIGOCLONAL CD8+ T CELLS PLAY A CRITICAL ROLE IN THE DEVELOPMENT OF HYPERTENSION

    PubMed Central

    Trott, Daniel W.; Thabet, Salim R; Kirabo, Annet; Saleh, Mohamed A.; Itani, Hana; Norlander, Allison E; Wu, Jing; Goldstein, Anna; Arendshorst, William J; Madhur, Meena S; Chen, Wei; Li, Chung-I; Shyr, Yu; Harrison, David G

    2014-01-01

    Recent studies have emphasized a role of adaptive immunity, and particularly T cells, in the genesis of hypertension. We sought to determine the T cell subtypes that contribute to hypertension and renal inflammation in angiotensin II-induced hypertension. Using T cell receptor (TCR) spectratyping to examine TCR usage we demonstrated that CD8+ cells, but not CD4+ cells, in the kidney exhibited altered TCR transcript lengths in V?3, 8.1 and 17 families in response to angiotensin II-induced hypertension. Clonality was not observed in other organs. The hypertension caused by angiotensin II in CD4?/? and MHCII?/? mice was similar to that observed in WT mice, while CD8?/? mice and OT1xRAG-1?/? mice, which have only one TCR, exhibited a blunted hypertensive response to angiotensin II. Adoptive transfer of pan-T cells and CD8+ T cells but not CD4+/CD25? cells conferred hypertension to RAG-1?/? mice. In contrast, transfer of CD4+/CD25+ cells to wild type mice receiving angiotensin II decreased blood pressure. Mice treated with angiotensin II exhibited increased numbers of kidney CD4+ and CD8+ T cells. In response to a sodium/volume challenge, wild type and CD4?/? mice infused with angiotensin II retained water and sodium whereas CD8?/? mice did not. CD8?/? mice were also protected against angiotensin-induced endothelial dysfunction and vascular remodeling in the kidney. These data suggest that in the development of hypertension, an oligoclonal population of CD8+ cells accumulate in the kidney and likely contribute to hypertension by contributing to sodium and volume retention and vascular rarefaction. PMID:25259750

  6. BTB-ZF Protein Znf131 Regulates Cell Growth of Developing and Mature T Cells.

    PubMed

    Iguchi, Tomohiro; Aoki, Kazuhisa; Ikawa, Tomokatsu; Taoka, Masato; Taya, Choji; Yoshitani, Hiroshi; Toma-Hirano, Makiko; Koiwai, Osamu; Isobe, Toshiaki; Kawamoto, Hiroshi; Masai, Hisao; Miyatake, Shoichiro

    2015-08-01

    Many members of the BTB-ZF family have been shown to play important roles in lymphocyte development and function. The role of zinc finger Znf131 (also known as Zbtb35) in T cell lineage was elucidated through the production of mice with floxed allele to disrupt at different stages of development. In this article, we present that Znf131 is critical for T cell development during double-negative to double-positive stage, with which significant cell expansion triggered by the pre-TCR signal is coupled. In mature T cells, Znf131 is required for the activation of effector genes, as well as robust proliferation induced upon TCR signal. One of the cyclin-dependent kinase inhibitors, p21(Cip1) encoded by cdkn1a gene, is one of the targets of Znf131. The regulation of T cell proliferation by Znf131 is in part attributed to its suppression on the expression of p21(Cip1). PMID:26136427

  7. Identification of human T cell antigens for the development of vaccines against Mycobacterium tuberculosis.

    PubMed

    Bertholet, Sylvie; Ireton, Gregory C; Kahn, Maria; Guderian, Jeffrey; Mohamath, Raodoh; Stride, Nicole; Laughlin, Elsa M; Baldwin, Susan L; Vedvick, Thomas S; Coler, Rhea N; Reed, Steven G

    2008-12-01

    Development of a subunit vaccine for Mycobacterium tuberculosis (Mtb) depends on the identification of Ags that induce appropriate T cell responses. Using bioinformatics, we selected a panel of 94 Mtb genes based on criteria that included growth in macrophages, up- or down-regulation under hypoxic conditions, secretion, membrane association, or because they were members of the PE/PPE or EsX families. Recombinant proteins encoded by these genes were evaluated for IFN-gamma recall responses using PBMCs from healthy subjects previously exposed to Mtb. From this screen, dominant human T cell Ags were identified and 49 of these proteins, formulated in CpG, were evaluated as vaccine candidates in a mouse model of tuberculosis. Eighteen of the individual Ags conferred partial protection against challenge with virulent Mtb. A combination of three of these Ags further increased protection against Mtb to levels comparable to those achieved with bacillus Calmette-Guérin vaccination. Vaccine candidates that led to reduction in lung bacterial burden following challenge-induced pluripotent CD4 and CD8 T cells, including Th1 cell responses characterized by elevated levels of Ag-specific IgG2c, IFN-gamma, and TNF. Priority vaccine Ags elicited pluripotent CD4 and CD8 T responses in purified protein derivative-positive donor PBMCs. This study identified numerous novel human T cell Ags suitable to be included in subunit vaccines against tuberculosis. PMID:19017986

  8. Cutting Edge: Codeletion of the Ras GTPase-Activating Proteins (RasGAPs) Neurofibromin 1 and p120 RasGAP in T Cells Results in the Development of T Cell Acute Lymphoblastic Leukemia.

    PubMed

    Lubeck, Beth A; Lapinski, Philip E; Oliver, Jennifer A; Ksionda, Olga; Parada, Luis F; Zhu, Yuan; Maillard, Ivan; Chiang, Mark; Roose, Jeroen; King, Philip D

    2015-07-01

    Ras GTPase-activating proteins (RasGAPs) inhibit signal transduction initiated through the Ras small GTP-binding protein. However, which members of the RasGAP family act as negative regulators of T cell responses is not completely understood. In this study, we investigated potential roles for the RasGAPs RASA1 and neurofibromin 1 (NF1) in T cells through the generation and analysis of T cell-specific RASA1 and NF1 double-deficient mice. In contrast to mice lacking either RasGAP alone in T cells, double-deficient mice developed T cell acute lymphoblastic leukemia/lymphoma, which originated at an early point in T cell development and was dependent on activating mutations in the Notch1 gene. These findings highlight RASA1 and NF1 as cotumor suppressors in the T cell lineage. PMID:26002977

  9. Primate lentiviral Nef proteins deregulate T-cell development by multiple mechanisms

    PubMed Central

    2013-01-01

    Background A nef gene is present in all primate lentiviral genomes and is important for high viral loads and progression to AIDS in human or experimental macaque hosts of HIV or SIV, respectively. In these hosts, infection of the thymus results in a decreased output of naive T cells that may contribute to the development of immunodeficiency. We have previously shown that HIV-1 subtype B Nef proteins can block human T-cell development. However, the underlying mechanism(s) and the conservation of this Nef function between different groups of HIV and SIV remained to be determined. Results We investigated whether reduction of thymic output is a conserved function of highly divergent lentiviral Nef proteins including those from both types of human immunodeficiency viruses (HIV-1 and HIV-2), their direct simian counterparts (SIVcpz, SIVgor and SIVsmm, respectively), and some additional SIV strains. We found that expression of most of these nef alleles in thymocyte progenitors impaired T-cell development and reduced thymic output. For HIV-1 Nef, binding to active p21 protein (Cdc42/Rac)-activated kinase (PAK2) was a major determinant of this function. In contrast, selective disruption of PAK2 binding did not eliminate the effect on T-cell development of SIVmac239 Nef, as was shown by expressing mutants in a newly discovered PAK2 activating structural motif (PASM) constituted by residues I117, H121, T218 and Y221, as well as previously described mutants. Rather, down-modulation of cell surface CD3 was sufficient for reduced thymic output by SIVmac Nef, while other functions of SIV Nefs contributed. Conclusions Our results indicate that primate lentiviral Nef proteins impair development of thymocyte precursors into T cells in multiple ways. The interaction of HIV-1 Nef with active PAK2 by HIV-1 seem to be most detrimental, and downregulation of CD3 by HIV-2 and most SIV Nef proteins sufficient for reduced thymic output. Since the reduction of thymic output by Nef is a conserved property of divergent lentiviruses, it is likely to be relevant for peripheral T-cell depletion in poorly adapted primate lentiviral infections. PMID:24237970

  10. Vav1 Acidic Region Tyrosine 174 Is Required for the Formation of T Cell Receptor-induced Microclusters and Is Essential in T Cell Development and Activation*S

    PubMed Central

    Miletic, Ana V.; Sakata-Sogawa, Kumiko; Hiroshima, Michio; Hamann, Michael J.; Gomez, Timothy S.; Ota, Naruhisa; Kloeppel, Tracie; Kanagawa, Osami; Tokunaga, Makio; Billadeau, Daniel D.; Swat, Wojciech

    2007-01-01

    Vav proteins are multidomain signaling molecules critical for mediating signals downstream of several surface receptors, including the antigen receptors of T and B lymphocytes. The catalytic guanine nucleotide exchange factor (GEF) activity of the Vav Dbl homology (DH) domain is thought to be controlled by an intramolecular autoinhibitory mechanism involving an N-terminal extension and phosphorylation of tyrosine residues in the acidic region (AC). Here, we report that the sequences surrounding the Vav1 AC: Tyr142, Tyr160, and Tyr174 are evolutionarily conserved, conform to consensus SH2 domain binding motifs, and bind several proteins implicated in TCR signaling, including Lck, PI3K p85?, and PLC?1, through direct interactions with their SH2 domains. In addition, the AC tyrosines regulate tyrosine phosphorylation of Vav1. We also show that Tyr174 is required for the maintenance of TCR-signaling microclusters and for normal T cell development and activation. In this regard, our data demonstrate that while Vav1 Tyr174 is essential for maintaining the inhibitory constraint of the DH domain in both developing and mature T cells, constitutively activated Vav GEF disrupts TCR-signaling microclusters and leads to defective T cell development and proliferation. PMID:17050525

  11. Development of T cell lymphoma in HTLV-1 bZIP factor and Tax double transgenic mice.

    PubMed

    Zhao, Tiejun; Satou, Yorifumi; Matsuoka, Masao

    2014-07-01

    Adult T-cell leukemia (ATL) is an aggressive T-cell malignancy caused by human T-cell leukemia virus type 1 (HTLV-1). ATL cells possess a CD4+ CD25+ phenotype, similar to that of regulatory T cells (Tregs). Tax has been reported to play a crucial role in the leukemogenesis of HTLV-1. The HTLV-1 bZIP factor (HBZ), which is encoded by the minus strand of the viral genomic RNA, is expressed in all ATL cases and induces neoplastic and inflammatory disease in vivo. To test whether HBZ and Tax are both required for T cell malignancy, we generated HBZ/Tax double transgenic mice in which HBZ and Tax are expressed exclusively in CD4+ T cells. Survival was much reduced in HBZ/Tax double-transgenic mice compared with wild type littermates. Transgenic expression of HBZ and Tax induced skin lesions and T-cell lymphoma in mice, resembling diseases observed in HTLV-1 infected individuals. However, Tax single transgenic mice did not develop major health problems. In addition, memory CD4+ T cells and Foxp3+ Treg cells counts were increased in HBZ/Tax double transgenic mice, and their proliferation was enhanced. There was very little difference between HBZ single and HBZ/Tax double transgenic mice. Taken together, these results show that HBZ, in addition to Tax, plays a critical role in T-cell lymphoma arising from HTLV-1 infection. PMID:24818712

  12. How specificity for self-peptides shapes the development and function of regulatory T cells

    PubMed Central

    Simons, Donald M.; Picca, Cristina Cozzo; Oh, Soyoung; Perng, Olivia A.; Aitken, Malinda; Erikson, Jan; Caton, Andrew J.

    2010-01-01

    The cataclysmic disease that develops in mice and humans lacking CD4+ T cells expressing the transcription factor Foxp3 has provided abundant evidence that Foxp3+CD4+ Tregs are required to suppress a latent autoreactivity of the immune system. There is also evidence for the existence of tissue-specific Tregs that can act to suppress regional autoimmune responses, suggesting that Tregs exert their effects, in part, through responding to self-peptides. However, how the immune system generates a repertoire of Tregs that is designed to recognize and direct regulatory function to self-peptides is incompletely understood. This review describes studies aimed at determining how T cell recognition of self-peptide(s) directs Treg formation in the thymus, including discussion of a modified “avidity” model of thymocyte development. Studies aimed at determining how TCR specificity contributes to the ability of Tregs to suppress autoimmune diseases are also discussed. PMID:20495071

  13. Gamma delta T cell responses associated with the development of tuberculosis in health care workers.

    PubMed

    Ordway, Diane J; Pinto, Luisa; Costa, Leonor; Martins, Marta; Leandro, Clara; Viveiros, Miguel; Amaral, Leonard; Arroz, Maria J; Ventura, Fernando A; Dockrell, Hazel M

    2005-03-01

    This study evaluated T cell immune responses to purified protein derivative (PPD) and Mycobacterium tuberculosis (Mtb) in health care workers who remained free of active tuberculosis (HCWs w/o TB), health care workers who went on to develop active TB (HCWs w/TB), non-health care workers who were TB free (Non-HCWs) and tuberculosis patients presenting with minimal (Min TB) or advanced (Adv TB) disease. Peripheral blood mononuclear cells (PBMC) were stimulated with Mtb and PPD and the expression of T cell activation markers CD25+ and HLA-DR+, intracellular IL-4 and IFN-gamma production and cytotoxic responses were evaluated. PBMC from HCWs who developed TB showed decreased percentages of cells expressing CD8+CD25+ in comparison to HCWs who remained healthy. HCWs who developed TB showed increased gammadelta TCR+ cell cytotoxicity and decreased CD3+gammadelta TCR- cell cytotoxicity in comparison to HCWs who remained healthy. PBMC from TB patients with advanced disease showed decreased percentages of CD25+CD4+ and CD25+CD8+ T cells that were associated with increased IL-4 production in CD8+ and gammadelta TCR+ phenotypes, in comparison with TB patients presenting minimal disease. TB patients with advanced disease showed increased gammadelta TCR+ cytotoxicity and reduced CD3+gammadelta TCR- cell cytotoxicity. Our results suggest that HCWs who developed TB show an early compensatory mechanism involving an increase in lytic responses of gammadelta TCR+ cells which did not prevent TB. PMID:15708307

  14. T cell development involves TRAF3IP3-mediated ERK signaling in the Golgi.

    PubMed

    Zou, Qiang; Jin, Jin; Xiao, Yichuan; Hu, Hongbo; Zhou, Xiaofei; Jie, Zuliang; Xie, Xiaoping; Li, James Y H; Cheng, Xuhong; Sun, Shao-Cong

    2015-07-27

    Generation of T lymphocytes in the thymus is guided by signal transduction from the T cell receptor (TCR), but the underlying mechanism is incompletely understood. Here we have identified a Golgi-associated factor, TRAF3-interacting protein 3 (TRAF3IP3), as a crucial mediator of thymocyte development. TRAF3IP3 deficiency in mice attenuates the generation of mature thymocytes caused by impaired thymocyte-positive selection. TRAF3IP3 mediates TCR-stimulated activation of the mitogen-activated protein kinase (MAPK) extracellular signal-regulated kinase (ERK) and its upstream kinase mitogen/extracellular signal-regulated kinase (MEK). Interestingly, TRAF3IP3 exerts this signaling function through recruiting MEK to the Golgi and, thereby, facilitating the interaction of MEK with its activator BRAF. Transgenic expression of a constitutively active MEK rescues the T cell development block in Traf3ip3 knockout mice. These findings establish TRAF3IP3 as a novel regulator of T cell development and suggest a Golgi-specific ERK signaling mechanism that regulates thymocyte development. PMID:26195727

  15. Differential effect of DJ-1/PARK7 on development of natural and induced regulatory T cells

    PubMed Central

    Singh, Yogesh; Chen, Hong; Zhou, Yuetao; Föller, Michael; Mak, Tak W.; Salker, Madhuri S.; Lang, Florian

    2015-01-01

    Regulatory T cells (Tregs) are essential for maintaining an effective immune tolerance and a homeostatic balance of various other immune cells. To manipulate the immune response during infections and autoimmune disorders, it is essential to know which genes or key molecules are involved in the development of Tregs. Transcription factor Foxp3 is required for the development of Tregs and governs most of the suppressive functions of these cells. Inhibited PI3K/AKT/mTOR signalling is critical for Foxp3 stability. Previous studies have suggested that DJ-1 or PARK7 protein is a positive regulator of the PI3K/AKT/mTOR pathway by negatively regulating the activity of PTEN. Thus, we hypothesised that a lack of DJ-1 could promote the development of Tregs. As a result, loss of DJ-1 decreased the total CD4+ T cell numbers but increased the fraction of thymic and peripheral nTregs. In contrast, Foxp3 generation was not augmented following differentiation of DJ-1-deficient naïve CD4+ T cells. DJ-1-deficient-iTregs were imperfect in replication, proliferation and more prone to cell death. Furthermore, DJ-1 deficient iTregs were less sensitive to pSmad2 and pStat5 signalling but had activated AKT/mTOR signalling. These observations reveal an unexpected differential role of DJ-1 in the development of nTregs and iTregs. PMID:26634899

  16. 78 FR 69429 - Prospective Grant of Exclusive License: The Development of Modified T-cells for the Treatment of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-19

    ...License: The Development of Modified T-cells for the Treatment of Multiple Myeloma AGENCY...Chimeric Antigen Receptors Targeting B-cell Maturation Antigen'' [HHS Ref. E-040-2012...receptor (CAR)-expressing human T-cells directed against B-cell Maturation...

  17. The Nuclear Receptor Nr4a1 Controls CD8 T Cell Development Through Transcriptional Suppression of Runx3

    PubMed Central

    Nowyhed, Heba N.; Huynh, Tridu R.; Blatchley, Amy; Wu, Runpei; Thomas, Graham D.; Hedrick, Catherine C.

    2015-01-01

    The NR4A nuclear receptor family member Nr4a1 is strongly induced in thymocytes undergoing selection, and has been shown to control the development of Treg cells; however the role of Nr4a1 in CD8+ T cells remains undefined. Here we report a novel role for Nr4a1 in regulating the development and frequency of CD8+ T cells through direct transcriptional control of Runx3. We discovered that Nr4a1 recruits the corepressor, CoREST to suppress Runx3 expression in CD8+ T cells. Loss of Nr4a1 results in increased Runx3 expression in thymocytes which consequently causes a 2-fold increase in the frequency and total number of intrathymic and peripheral CD8+ T cells. Our findings establish Nr4a1 as a novel and critical player in the regulation of CD8 T cell development through the direct suppression of Runx3. PMID:25762306

  18. The nuclear receptor nr4a1 controls CD8 T cell development through transcriptional suppression of runx3.

    PubMed

    Nowyhed, Heba N; Huynh, Tridu R; Blatchley, Amy; Wu, Runpei; Thomas, Graham D; Hedrick, Catherine C

    2015-01-01

    The NR4A nuclear receptor family member Nr4a1 is strongly induced in thymocytes undergoing selection, and has been shown to control the development of Treg cells; however the role of Nr4a1 in CD8(+) T cells remains undefined. Here we report a novel role for Nr4a1 in regulating the development and frequency of CD8(+) T cells through direct transcriptional control of Runx3. We discovered that Nr4a1 recruits the corepressor, CoREST to suppress Runx3 expression in CD8(+) T cells. Loss of Nr4a1 results in increased Runx3 expression in thymocytes which consequently causes a 2-fold increase in the frequency and total number of intrathymic and peripheral CD8(+) T cells. Our findings establish Nr4a1 as a novel and critical player in the regulation of CD8 T cell development through the direct suppression of Runx3. PMID:25762306

  19. New Insights into the Roles of Stat5a/b and Stat3 in T Cell Development and Differentiation

    PubMed Central

    Wei, Lai; Laurence, Arian; O'Shea, John J.

    2009-01-01

    T cell development and differentiation is carefully orchestrated by a series of cytokines. The importance of STAT family proteins in mediating signals by these cytokines is well-known, but new information on the role of STATs in novel aspects of T cell function and new T cell subsets continues to accumulate. Recent studies have placed Stat5a/b and Stat3 center stage in T cell development and differentiation. Stat5a/b are indispensable in T regulatory (Treg) cell development and maintenance, and negatively regulate T helper 17 (Th17) cell differentiation. Conversely, Stat3 is essential for Th17 differentiation and inhibits Treg cells. The balance of Treg and Th17 cells is thought to be critical in maintaining immune tolerance, while preserving effective host defense. Therefore, Stat5a/b and Stat3 are emerging to be key players in T cell differentiation and homeostasis. PMID:18708155

  20. Heme exporter FLVCR is required for T cell development and peripheral survival.

    PubMed

    Philip, Mary; Funkhouser, Scott A; Chiu, Edison Y; Phelps, Susan R; Delrow, Jeffrey J; Cox, James; Fink, Pamela J; Abkowitz, Janis L

    2015-02-15

    All aerobic cells and organisms must synthesize heme from the amino acid glycine and the tricarboxylic acid cycle intermediate succinyl CoA for incorporation into hemoproteins, such as the cytochromes needed for oxidative phosphorylation. Most studies on heme regulation have been done in erythroid cells or hepatocytes; however, much less is known about heme metabolism in other cell types. The feline leukemia virus subgroup C receptor (FLVCR) is a 12-transmembrane domain surface protein that exports heme from cells, and it was shown to be required for erythroid development. In this article, we show that deletion of Flvcr in murine hematopoietic precursors caused a complete block in ?? T cell development at the CD4(+)CD8(+) double-positive stage, although other lymphoid lineages were not affected. Moreover, FLVCR was required for the proliferation and survival of peripheral CD4(+) and CD8(+) T cells. These studies identify a novel and unexpected role for FLVCR, a major facilitator superfamily metabolite transporter, in T cell development and suggest that heme metabolism is particularly important in the T lineage. PMID:25582857

  1. IL-15 receptor ? signaling constrains the development of IL-17-producing ?? T cells.

    PubMed

    Colpitts, Sara L; Puddington, Lynn; Lefrançois, Leo

    2015-08-01

    The development and homeostasis of ?? T cells is highly dependent on distinct cytokine networks. Here we examine the role of IL-15 and its unique receptor, IL-15R?, in the development of IL-17-producing ?? (??-17) T cells. Phenotypic analysis has shown that CD44(high) ??-17 cells express IL-15R? and the common gamma chain (CD132), yet lack the IL-2/15R? chain (CD122). Surprisingly, we found an enlarged population of ??-17 cells in the peripheral and mesenteric lymph nodes of adult IL-15R? KO mice, but not of IL-15 KO mice. The generation of mixed chimeras from neonatal thymocytes indicated that cell-intrinsic IL-15R? expression was required to limit IL-17 production by ?? T cells. ??-17 cells also were increased in the peripheral lymph nodes of transgenic knock-in mice, where the IL-15R? intracellular signaling domain was replaced with the intracellular portion of the IL-2R? chain (that lacks signaling capacity). Finally, an analysis of neonatal thymi revealed that the CD44(lo/int) precursors of ??-17 cells, which also expressed IL-15R?, were increased in newborn mice deficient in IL-15R? signaling, but not in IL-15 itself. Thus, these findings demonstrate that signaling through IL-15R? regulates the development of ??-17 cells early in ontogeny, with long-term effects on their peripheral homeostasis in the adult. PMID:26195801

  2. Antibody persistence and T-cell balance: Two key factors confronting HIV vaccine development

    PubMed Central

    Lewis, George K.; DeVico, Anthony L.; Gallo, Robert C.

    2014-01-01

    The quest for a prophylactic AIDS vaccine is ongoing, but it is now clear that the successful vaccine must elicit protective antibody responses. Accordingly, intense efforts are underway to identify immunogens that elicit these responses. Regardless of the mechanism of antibody-mediated protection, be it neutralization, Fc-mediated effector function, or both, antibody persistence and appropriate T-cell help are significant problems confronting the development of a successful AIDS vaccine. Here, we discuss the evidence illustrating the poor persistence of antibody responses to Env, the envelope glycoprotein of HIV-1, and the related problem of CD4+ T-cell responses that compromise vaccine efficacy by creating excess cellular targets of HIV-1 infection. Finally, we propose solutions to both problems that are applicable to all Env-based AIDS vaccines regardless of the mechanism of antibody-mediated protection. PMID:25349379

  3. Impairment of T cell development and acute inflammatory response in HIV-1 Tat transgenic mice

    PubMed Central

    Fiume, Giuseppe; Scialdone, Annarita; Albano, Francesco; Rossi, Annalisa; Maria Tuccillo, Franca; Rea, Domenica; Palmieri, Camillo; Caiazzo, Elisabetta; Cicala, Carla; Bellevicine, Claudio; Falcone, Cristina; Vecchio, Eleonora; Pisano, Antonio; Ceglia, Simona; Mimmi, Selena; Iaccino, Enrico; Laurentiis, Annamaria de; Pontoriero, Marilena; Agosti, Valter; Troncone, Giancarlo; Mignogna, Chiara; Palma, Giuseppe; Arra, Claudio; Mallardo, Massimo; Maria Buonaguro, Franco; Scala, Giuseppe; Quinto, Ileana

    2015-01-01

    Immune activation and chronic inflammation are hallmark features of HIV infection causing T-cell depletion and cellular immune dysfunction in AIDS. Here, we addressed the issue whether HIV-1 Tat could affect T cell development and acute inflammatory response by generating a transgenic mouse expressing Tat in lymphoid tissue. Tat-Tg mice showed thymus atrophy and the maturation block from DN4 to DP thymic subpopulations, resulting in CD4+ and CD8+ T cells depletion in peripheral blood. In Tat-positive thymus, we observed the increased p65/NF-?B activity and deregulated expression of cytokines/chemokines and microRNA-181a-1, which are involved in T-lymphopoiesis. Upon LPS intraperitoneal injection, Tat-Tg mice developed an abnormal acute inflammatory response, which was characterized by enhanced lethality and production of inflammatory cytokines. Based on these findings, Tat-Tg mouse could represent an animal model for testing adjunctive therapies of HIV-1-associated inflammation and immune deregulation. PMID:26343909

  4. Impairment of T cell development and acute inflammatory response in HIV-1 Tat transgenic mice.

    PubMed

    Fiume, Giuseppe; Scialdone, Annarita; Albano, Francesco; Rossi, Annalisa; Tuccillo, Franca Maria; Rea, Domenica; Palmieri, Camillo; Caiazzo, Elisabetta; Cicala, Carla; Bellevicine, Claudio; Falcone, Cristina; Vecchio, Eleonora; Pisano, Antonio; Ceglia, Simona; Mimmi, Selena; Iaccino, Enrico; de Laurentiis, Annamaria; Pontoriero, Marilena; Agosti, Valter; Troncone, Giancarlo; Mignogna, Chiara; Palma, Giuseppe; Arra, Claudio; Mallardo, Massimo; Buonaguro, Franco Maria; Scala, Giuseppe; Quinto, Ileana

    2015-01-01

    Immune activation and chronic inflammation are hallmark features of HIV infection causing T-cell depletion and cellular immune dysfunction in AIDS. Here, we addressed the issue whether HIV-1 Tat could affect T cell development and acute inflammatory response by generating a transgenic mouse expressing Tat in lymphoid tissue. Tat-Tg mice showed thymus atrophy and the maturation block from DN4 to DP thymic subpopulations, resulting in CD4(+) and CD8(+) T cells depletion in peripheral blood. In Tat-positive thymus, we observed the increased p65/NF-?B activity and deregulated expression of cytokines/chemokines and microRNA-181a-1, which are involved in T-lymphopoiesis. Upon LPS intraperitoneal injection, Tat-Tg mice developed an abnormal acute inflammatory response, which was characterized by enhanced lethality and production of inflammatory cytokines. Based on these findings, Tat-Tg mouse could represent an animal model for testing adjunctive therapies of HIV-1-associated inflammation and immune deregulation. PMID:26343909

  5. Ionizing radiation and autoimmunity: Induction of autoimmune disease in mice by high dose fractionated total lymphoid irradiation and its prevention by inoculating normal T cells

    SciTech Connect

    Sakaguchi, N.; Sakaguchi, S. Scripps Research Institute, La Jolla, CA PRESTO, JRDC, Institute of Phical and Chemical Research, Tsukuba, Ibaraki ); Miyai, K. )

    1992-11-01

    Ionizing radiation can functionally alter the immune system and break self-tolerance. High dose (42.5 Gy), fractionated (2.5 Gy 17 times) total lymphoid irradiation (TLI) on mice caused various organ-specific autoimmune diseases, such as gastritis, thyroiditis, and orchitis, depending on the radiation dosages, the extent of lymphoid irradiation, and the genetic background of the mouse strains. Radiation-induced tissue damage is not the primary cause of the autoimmune disease because irradiation of the target organs alone failed to elicit the autoimmunity and shielding of the organs from irradiation was unable to prevent it. In contrast, irradiation of both the thymus and the peripheral lymphoid organs/tissues was required for efficient induction of autoimmune disease by TLI. TLI eliminated the majority of mature thymocytes and the peripheral T cells for 1 mo, and inoculation of spleen cell, thymocyte, or bone marrow cell suspensions (prepared from syngeneic nonirradiated mice) within 2 wk after TLI effectively prevented the autoimmune development. Depletion of T cells from the inocula abrogated the preventive activity. CD4[sup +] T cells mediated the autoimmune prevention but CD8[sup +] T cells did not. CD4[sup +] T cells also appeared to mediate the TLI-induced autoimmune disease because CD4[sup +] T cells from disease-bearing TLI mice adoptively transferred the autoimmune disease to syngeneic naive mice. Taken together, these results indicate that high dose, fractionated ionizing radiation on the lymphoid organs/tissues can cause autoimmune disease by affecting the T cell immune system, rather than the target self-Ags, presumably by altering T cell-dependent control of self-reactive T cells. 62 refs., 9 figs., 2 tabs.

  6. Helios-positive functional regulatory T cells are decreased in decidua of miscarriage cases with normal fetal chromosomal content.

    PubMed

    Inada, Kumiko; Shima, Tomoko; Ito, Mika; Ushijima, Akemi; Saito, Shigeru

    2015-02-01

    Regulatory (Treg) T cells play essential roles in the maintenance of allogeneic pregnancy in mice and humans. Recent data show that Foxp3 expression occurs in both immuno-suppressive Treg and -nonsuppressive effector T (Teff) cells upon activation in humans. Samstein et al. (2012) reported that inducible Treg (iTreg) cells enforce maternal-fetal tolerance in placental mammals. Therefore, we should reanalyze which types of Treg cell play an important role in the maintenance of allogeneic pregnancy. In this study, we studied the frequencies of naïve Treg cells, effector Treg cells, Foxp3(+) Teff cells, Helios(+) naturally occurring Treg (nTreg) cells, and Helios(-) iTreg cells using flow cytometry. The frequencies of effector Treg cells and Foxp3(+) Teff cells among CD4(+)Foxp3(+) cells in the decidua of miscarriage cases with a normal embryo karyotype (n=8) were significantly lower (P=0.0105) and significantly higher (P=0.0258) than those in normally progressing pregnancies (n=11), respectively. However, these frequencies in miscarriages with an abnormal embryo karyotype (n=15) were similar to those in normally progressing pregnancies. The frequencies of these cell populations in the three groups were unchanged in peripheral blood; on the other hand, most of the effector Treg cells in the decidua were Helios(+) nTreg cells and these frequencies were significantly higher than those in peripheral blood, while those among effector Treg and naïve Treg cells in the decidua and peripheral blood were similar among the three groups. These data suggest that decreased Helios(+) effector nTreg might play an important role in the maintenance of pregnancy in humans. PMID:25453751

  7. Spontaneous Intestinal Tumorigenesis in Apc (/Min+) Mice Requires Altered T Cell Development with IL-17A.

    PubMed

    Chae, Wook-Jin; Bothwell, Alfred L M

    2015-01-01

    The control of inflammatory diseases requires functional regulatory T cells (Tregs) with significant Gata-3 expression. Here we address the inhibitory role of Tregs on intestinal tumorigenesis in the Apc (/Min+) mouse model that resembles human familial adenomatous polyposis (FAP). Apc (/Min+) mice had a markedly increased frequency of Foxp3+ Tregs and yet decreased Gata-3 expression in the lamina propria. To address the role of heterozygous Apc gene mutation in Tregs, we generated Foxp3-Cre, Apc (flox/+) mice. Tregs from these mice effectively inhibited tumorigenesis comparable to wild type Tregs after adoptive transfer into Apc (/Min+) mice, demonstrating that the heterozygous Apc gene mutation in Tregs does not induce the loss of control over tumor microenvironment. Adoptive transfer of in vitro generated Apc (/Min+) iTregs (inducible Tregs) failed to inhibit intestinal tumorigenesis, suggesting that naïve CD4 T cells generated from Apc (/Min+) mice thymus were impaired. We also showed that adoptively transferred IL-17A-deficient Apc (/Min+) Tregs inhibited tumor growth, suggesting that IL-17A was critical to impair the tumor regression function of Apc (/Min+) Tregs. Taken together, our results suggest that both T cell development in a functional thymus and IL-17A control the ability of Treg to inhibit intestinal tumorigenesis in Apc (/Min+) mice. PMID:26146642

  8. A genome-wide regulatory network identifies key transcription factors for memory CD8[superscript +] T-cell development

    E-print Network

    Hu, Guangan

    Memory CD8[superscript +] T-cell development is defined by the expression of a specific set of memory signature genes. Despite recent progress, many components of the transcriptional control of memory CD8[superscript +] ...

  9. Noninvasive In Toto Imaging of the Thymus Reveals Heterogeneous Migratory Behavior of Developing T Cells.

    PubMed

    Bajoghli, Baubak; Kuri, Paola; Inoue, Daigo; Aghaallaei, Narges; Hanelt, Marleen; Thumberger, Thomas; Rauzi, Matteo; Wittbrodt, Joachim; Leptin, Maria

    2015-09-01

    The migration of developing T cells (thymocytes) between distinct thymic microenvironments is crucial for their development. Ex vivo studies of thymus tissue explants suggest two distinct migratory behaviors of thymocytes in the thymus. In the cortex, thymocytes exhibit a stochastic migration, whereas medullary thymocytes show confined migratory behavior. Thus far, it has been difficult to follow all thymocytes in an entire thymus and relate their differentiation steps to their migratory dynamics. To understand the spatial organization of the migratory behavior and development of thymocytes in a fully functional thymus, we developed transgenic reporter lines for the chemokine receptors ccr9a and ccr9b, as well as for rag2, and used them for noninvasive live imaging of the entire thymus in medaka (Oryzias latipes). We found that the expression of these two chemokine receptors in the medaka juvenile thymus defined two spatially distinct subpopulations of thymocytes. Landmark events of T cell development including proliferation, somatic recombination, and thymic selection can be mapped to subregions of the thymus. The migratory behavior of thymocytes within each of the subpopulations is equally heterogeneous, and specific migratory behaviors are not associated with particular domains in the thymus. During the period when thymocytes express rag2 their migratory behavior was more homogeneous. Therefore, the migratory behavior of thymocytes is partly correlated with their developmental stage rather than being defined by their spatial localization. PMID:26188059

  10. The ubiquitin-specific protease USP8 is critical for the development and homeostasis of T cells.

    PubMed

    Dufner, Almut; Kisser, Agnes; Niendorf, Sandra; Basters, Anja; Reissig, Sonja; Schönle, Anne; Aichem, Annette; Kurz, Thorsten; Schlosser, Andreas; Yablonski, Deborah; Groettrup, Marcus; Buch, Thorsten; Waisman, Ari; Schamel, Wolfgang W; Prinz, Marco; Knobeloch, Klaus-Peter

    2015-09-01

    The modification of proteins by ubiquitin has a major role in cells of the immune system and is counteracted by various deubiquitinating enzymes (DUBs) with poorly defined functions. Here we identified the ubiquitin-specific protease USP8 as a regulatory component of the T cell antigen receptor (TCR) signalosome that interacted with the adaptor Gads and the regulatory molecule 14-3-3?. Caspase-dependent processing of USP8 occurred after stimulation of the TCR. T cell-specific deletion of USP8 in mice revealed that USP8 was essential for thymocyte maturation and upregulation of the gene encoding the cytokine receptor IL-7R? mediated by the transcription factor Foxo1. Mice with T cell-specific USP8 deficiency developed colitis that was promoted by disturbed T cell homeostasis, a predominance of CD8(+) ?? T cells in the intestine and impaired regulatory T cell function. Collectively, our data reveal an unexpected role for USP8 as an immunomodulatory DUB in T cells. PMID:26214742

  11. HIV-1 transgenic rat CD4+ T cells develop decreased CD28 responsiveness and suboptimal Lck tyrosine dephosphorylation following activation

    SciTech Connect

    Yadav, Anjana; Pati, Shibani; Nyugen, Anhthu; Barabitskaja, Oxana; Mondal, Prosanta; Anderson, Michael; Gallo, Robert C.; Huso, David L.; Reid, William . E-mail: reid@umbi.umd.edu

    2006-09-30

    Impaired CD4+ T cell responses, resulting in dysregulated T-helper 1 (Th1) effector and memory responses, are a common result of HIV-1 infection. These defects are often preceded by decreased expression and function of the {alpha}/{beta} T cell receptor (TCR)-CD3 complex and of co-stimulatory molecules including CD28, resulting in altered T cell proliferation, cytokine secretion and cell survival. We have previously shown that HIV Tg rats have defective development of T cell effector function and generation of specific effector/memory T cell subsets. Here we identify abnormalities in activated HIV-1 Tg rat CD4+ T cells that include decreased pY505 dephosphorylation of Lck (required for Lck activation), decreased CD28 function, reduced expression of the anti-apoptotic molecule Bcl-xL, decreased secretion of the mitogenic lympokine interleukin-2 (IL-2) and increased activation induced apoptosis. These events likely lead to defects in antigen-specific signaling and may help explain the disruption of Th1 responses and the generation of specific effector/memory subsets in transgenic CD4+ T cells.

  12. Interferon-? Promotes Inflammation and Development of T-Cell Lymphoma in HTLV-1 bZIP Factor Transgenic Mice

    PubMed Central

    Mitagami, Yu; Yasunaga, Jun-ichirou; Kinosada, Haruka; Ohshima, Koichi; Matsuoka, Masao

    2015-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) is an etiological agent of several inflammatory diseases and a T-cell malignancy, adult T-cell leukemia (ATL). HTLV-1 bZIP factor (HBZ) is the only viral gene that is constitutively expressed in HTLV-1-infected cells, and it has multiple functions on T-cell signaling pathways. HBZ has important roles in HTLV-1-mediated pathogenesis, since HBZ transgenic (HBZ-Tg) mice develop systemic inflammation and T-cell lymphomas, which are similar phenotypes to HTLV-1-associated diseases. We showed previously that in HBZ-Tg mice, HBZ causes unstable Foxp3 expression, leading to an increase in regulatory T cells (Tregs) and the consequent induction of IFN-?-producing cells, which in turn leads to the development of inflammation in the mice. In this study, we show that the severity of inflammation is correlated with the development of lymphomas in HBZ-Tg mice, suggesting that HBZ-mediated inflammation is closely linked to oncogenesis in CD4+ T cells. In addition, we found that IFN-?-producing cells enhance HBZ-mediated inflammation, since knocking out IFN-? significantly reduced the incidence of dermatitis as well as lymphoma. Recent studies show the critical roles of the intestinal microbiota in the development of Tregs in vivo. We found that even germ-free HBZ-Tg mice still had an increased number of Tregs and IFN-?-producing cells, and developed dermatitis, indicating that an intrinsic activity of HBZ evokes aberrant T-cell differentiation and consequently causes inflammation. These results show that immunomodulation by HBZ is implicated in both inflammation and oncogenesis, and suggest a causal connection between HTLV-1-associated inflammation and ATL. PMID:26296091

  13. Interferon ? Derived from CD4+ T Cells Is Sufficient to Mediate T Helper Cell Type 1 Development

    PubMed Central

    Wakil, Adil E.; Wang, Zhi-En; Ryan, James C.; Fowell, Deborah J.; Locksley, Richard M.

    1998-01-01

    Interferon ? (IFN-?) has been implicated in T helper type 1 (Th1) cell development through its ability to optimize interleukin 12 (IL-12) production from macrophages and IL-12 receptor expression on activated T cells. Various systems have suggested a role for IFN-? derived from the innate immune system, particularly natural killer (NK) cells, in mediating Th1 differentiation in vivo. We tested this requirement by reconstituting T cell and IFN-? doubly deficient mice with wild-type CD4+ T cells and challenging the mice with pathogens that elicited either minimal or robust IL-12 in vivo (Leishmania major or Listeria monocytogenes, respectively). Th1 cells developed under both conditions, and this was unaffected by the presence or absence of IFN-? in non-T cells. Reconstitution with IFN-?–deficient CD4+ T cells could not reestablish control over L. major, even in the presence of IFN-? from the NK compartment. These data demonstrate that activated T cells can maintain responsiveness to IL-12 through elaboration of endogenous IFN-? without requirement for an exogenous source of this cytokine. PMID:9802977

  14. Development and Function of Protective and Pathologic Memory CD4 T Cells

    PubMed Central

    Jaigirdar, Shafqat Ahrar; MacLeod, Megan K. L.

    2015-01-01

    Immunological memory is one of the defining features of the adaptive immune system. As key orchestrators and mediators of immunity, CD4 T cells are central to the vast majority of adaptive immune responses. Generated following an immune response, memory CD4 T cells retain pertinent information about their activation environment enabling them to make rapid effector responses upon reactivation. These responses can either benefit the host by hastening the control of pathogens or cause damaging immunopathology. Here, we will discuss the diversity of the memory CD4 T cell pool, the signals that influence the transition of activated T cells into that pool, and highlight how activation requirements differ between naïve and memory CD4 T cells. A greater understanding of these factors has the potential to aid the design of more effective vaccines and to improve regulation of pathologic CD4 T cells, such as in the context of autoimmunity and allergy. PMID:26441961

  15. Engineered T Cells Targeting Tumor-Specific Mutations

    Cancer.gov

    Scientists at the National Cancer Institute's Surgery Branch have developed a method to identify and generate T-cell receptor (TCR) engineered T- cells for personalized cancer therapy. The TCR is a complex of integral membrane proteins that recognizes antigens and activates T cells. Human cancers contain genetic mutations that are unique in each patient. The researchers found cancer-specific mutations by sequencing tumors and comparing with normal cells.

  16. Development and characterization of Histoplasma capsulatum-reactive murine T-cell lines and clones

    NASA Technical Reports Server (NTRS)

    Deepe, George S., Jr.; Smith, James G.; Denman, David; Bullock, Ward E.; Sonnenfeld, Gerald

    1986-01-01

    Several Histoplasma capsulatum-reactive murine cloned T-cell lines (TCLs) were isolated from spleens of C57BL/6 mice immunized with viable H. capsulatum yeast cells, using the methodology of Kimoto and Fathman (1980). These T-cells were characterized phenotypically as Thy-1.2(+) Lyt-1(+) L3T4(+) Lyt-2(-), that is, as the helper/inducer phenotype. The cloned T cells proliferate in response to histoplasmin and, in some cases, to heterologous fungal anigens. Upon injection of mice with the antigen, the T-cells mediate local delayed-type hypersensitivity responses and, after stimulation, release regulatory lymphokines.

  17. [Comparative analysis of the role of CD4(+) and CD8(+) T cells in severe asthma development].

    PubMed

    Wang, X; Wang, J; Xing, C-Y; Zang, R; Pu, Y-Y; Yin, Z-X

    2015-01-01

    The role of CD8^(+) T cells in asthma has not been fully discussed. The mechanisms of CD4^(+) and CD8^(+) cells in severe asthma (SA) development were compared. The microarray data (GSE31773) was downloaded from the Gene Expression Omnibus (GEO) database, including 20 samples of CD4^(+) and CD8^(+) T cells, which were collected from 8 health controls (HC), 4 non-severe asthma (NSA) and 8 SA patients. DEGs of CD4^(+) and CD8^(+) T cells in the HC vs. NSA and HC vs. SA groups were identified using the limma package in R. GO and pathway enrichment analysis of the common DEGs between the two groups were analyzed using DAVID. The interactive network of DEGs and significant modules were further explored. In CD4^(+) cells, there were 168 DEGs in HC vs. NSA group and 685 DEGs in HC vs. SA group, while for CD8^(+) T cells there were 719 DEGs in the HC vs. NSA groups and 1255 DEGs in the HC vs. SA groups. Besides, 80 common DEGs from CD4^(+) samples were enriched in the MAPKKK cascade and molecular metabolism, and 385 common DEGs of CD8^(+) T cells were significantly related with cell apoptosis and transformation. Moreover, two significant modules of DEGs in CD4^(+) were found to be involved with MPO and BPI. One module of CD8^(+) T cells containing PDHA1 and MRPL42 was identified to be related with glycolysis. In conclusion, MPO and BPI in CD4^(+), and PDHA1 and MRPL42 in CD8^(+) T cells might be used as specific biomarkers of SA progression. Therapy targeting the functions of CD4^(+) and CD8^(+) T cells may provide a novel perspective for SA treatment. PMID:26107902

  18. Transfer of regulatory T cells into abortion-prone mice promotes the expansion of uterine mast cells and normalizes early pregnancy angiogenesis

    PubMed Central

    Woidacki, Katja; Meyer, Nicole; Schumacher, Anne; Goldschmidt, Alexandra; Maurer, Marcus; Zenclussen, Ana Claudia

    2015-01-01

    Implantation of the fertilized egg depends on the coordinated interplay of cells and molecules that prepare the uterus for this important event. In particular, regulatory T cells (Tregs) are key regulators as their ablation hinders implantation by rendering the uterus hostile for the embryo. In addition, the adoptive transfer of Tregs can avoid early abortion in mouse models. However, it is still not defined which mechanisms underlie Treg function during this early period. Cells of the innate immune system have been reported to support implantation, in part by promoting angiogenesis. In particular, uterine mast cells (uMCs) emerge as novel players at the fetal-maternal interface. Here, we studied whether the positive action of Tregs is based on the expansion of uMCs and the promotion of angiogenesis. We observed that abortion-prone mice have insufficient numbers of uMCs that could be corrected by the adoptive transfer of Tregs. This in turn positively influenced the remodeling of spiral arteries and placenta development as well as the levels of soluble fms-like tyrosine kinase 1 (sFlt-1). Our data suggest an interplay between Tregs and uMCs that is relevant for the changes required at the feto-maternal interface for the normal development of pregnancy. PMID:26355667

  19. Rational development and characterization of humanized anti-EGFR variant III chimeric antigen receptor T cells for glioblastoma.

    PubMed

    Johnson, Laura A; Scholler, John; Ohkuri, Takayuki; Kosaka, Akemi; Patel, Prachi R; McGettigan, Shannon E; Nace, Arben K; Dentchev, Tzvete; Thekkat, Pramod; Loew, Andreas; Boesteanu, Alina C; Cogdill, Alexandria P; Chen, Taylor; Fraietta, Joseph A; Kloss, Christopher C; Posey, Avery D; Engels, Boris; Singh, Reshma; Ezell, Tucker; Idamakanti, Neeraja; Ramones, Melissa H; Li, Na; Zhou, Li; Plesa, Gabriela; Seykora, John T; Okada, Hideho; June, Carl H; Brogdon, Jennifer L; Maus, Marcela V

    2015-02-18

    Chimeric antigen receptors (CARs) are synthetic molecules designed to redirect T cells to specific antigens. CAR-modified T cells can mediate long-term durable remissions in B cell malignancies, but expanding this platform to solid tumors requires the discovery of surface targets with limited expression in normal tissues. The variant III mutation of the epidermal growth factor receptor (EGFRvIII) results from an in-frame deletion of a portion of the extracellular domain, creating a neoepitope. We chose a vector backbone encoding a second-generation CAR based on efficacy of a murine scFv-based CAR in a xenograft model of glioblastoma. Next, we generated a panel of humanized scFvs and tested their specificity and function as soluble proteins and in the form of CAR-transduced T cells; a low-affinity scFv was selected on the basis of its specificity for EGFRvIII over wild-type EGFR. The lead candidate scFv was tested in vitro for its ability to direct CAR-transduced T cells to specifically lyse, proliferate, and secrete cytokines in response to antigen-bearing targets. We further evaluated the specificity of the lead CAR candidate in vitro against EGFR-expressing keratinocytes and in vivo in a model of mice grafted with normal human skin. EGFRvIII-directed CAR T cells were also able to control tumor growth in xenogeneic subcutaneous and orthotopic models of human EGFRvIII(+) glioblastoma. On the basis of these results, we have designed a phase 1 clinical study of CAR T cells transduced with humanized scFv directed to EGFRvIII in patients with either residual or recurrent glioblastoma (NCT02209376). PMID:25696001

  20. T Cells in Fish

    PubMed Central

    Nakanishi, Teruyuki; Shibasaki, Yasuhiro; Matsuura, Yuta

    2015-01-01

    Cartilaginous and bony fish are the most primitive vertebrates with a thymus, and possess T cells equivalent to those in mammals. There are a number of studies in fish demonstrating that the thymus is the essential organ for development of T lymphocytes from early thymocyte progenitors to functionally competent T cells. A high number of T cells in the intestine and gills has been reported in several fish species. Involvement of CD4+ and CD8?+ T cells in allograft rejection and graft-versus-host reaction (GVHR) has been demonstrated using monoclonal antibodies. Conservation of CD4+ helper T cell functions among teleost fishes has been suggested in a number studies employing mixed leukocyte culture (MLC) and hapten/carrier effect. Alloantigen- and virus-specific cytotoxicity has also been demonstrated in ginbuna and rainbow trout. Furthermore, the important role of cell-mediated immunity rather than humoral immunity has been reported in the protection against intracellular bacterial infection. Recently, the direct antibacterial activity of CD8?+, CD4+ T-cells and sIgM+ cells in fish has been reported. In this review, we summarize the recent progress in T cell research focusing on the tissue distribution and function of fish T cells. PMID:26426066

  1. Defective CD8 T Cell Memory Following Acute Infection Without CD4 T Cell Help

    NASA Astrophysics Data System (ADS)

    Sun, Joseph C.; Bevan, Michael J.

    2003-04-01

    The CD8+ cytotoxic T cell response to pathogens is thought to be CD4+ helper T cell independent because infectious agents provide their own inflammatory signals. Mice that lack CD4+ T cells mount a primary CD8 response to Listeria monocytogenes equal to that of wild-type mice and rapidly clear the infection. However, protective memory to a challenge is gradually lost in the former animals. Memory CD8+ T cells from normal mice can respond rapidly, but memory CD8+ T cells that are generated without CD4 help are defective in their ability to respond to secondary encounters with antigen. The results highlight a previously undescribed role for CD4 help in promoting protective CD8 memory development.

  2. Antigen-Bearing Dendritic Cells Regulate the Diverse Pattern of Memory CD8 T Cell Development in Different Tissues

    E-print Network

    Shen, Ching-Hung

    Memory T cells of the effector type (TEM) account for the characteristic rapidity of memory T-cell responses, whereas memory T cells of the central type (TCM) account for long-lasting, vigorously proliferating memory T-cell ...

  3. Functional CD8+ but not CD4+ T cell responses develop independent of thymic epithelial MHC

    PubMed Central

    Martinic, Marianne M.; van den Broek, Maries F.; Rülicke, Thomas; Huber, Christoph; Odermatt, Bernhard; Reith, Walter; Horvath, Edit; Zellweger, Raphael; Fink, Katja; Recher, Mike; Eschli, Bruno; Hengartner, Hans; Zinkernagel, Rolf M.

    2006-01-01

    The role of nonthymic epithelial (non-TE) MHC in T cell repertoire selection remains controversial. To analyze the relative roles of thymic epithelial (TE) and non-TE MHC in T cell repertoire selection, we have generated tetraparental aggregation chimeras (B6-nude?BALB/c and B6?BALB/c-nude) harboring T and B cells from both parents, whereas TE cells originated exclusively from the non-nude donor. These chimeras mounted protective virus-specific TE and non-TE MHC-restricted T cell responses. To further evaluate whether non-TE MHC alone was sufficient to generate a functional T cell repertoire, we generated tetraparental aggregation chimeras lacking MHC class II (B6-nude?MHCII?/?) or both MHC molecules (B6-nude?MHCI?/?II?/?) on TE cells, but not on cells of B6-nude origin. Chimeras with MHC-deficient TE cells mounted functional virus-specific CD8+ but not CD4+ T cell responses. Thus, maturation of functional CD4+ T cell responses required MHC class II on thymic epithelium, whereas CD8+ T cells matured in the absence of TE MHC. PMID:16983067

  4. Novel antibody approaches for T-cell lymphomas.

    PubMed

    Goodman, Oscar B; Dang, Nam H

    2008-12-01

    T-cell lymphomas are biologically more aggressive--and less responsive than their B-cell counterparts--to conventional chemotherapy. The understanding of the normal physiology of T-cell signaling as well as the pathophysiology of T-cell neoplasia has advanced dramatically in the past decade. Thus, a number of novel cell surface therapeutic targets specific for T-cells have been identified and evaluated as potential monoclonal antibody (MoAb)-based therapeutic targets. Herein, we review a number of these cell surface targets and discuss the development and the clinical evaluation of MoAb therapies directed against these antigens. PMID:19073527

  5. In vitro induction of non-responsiveness in cloned normal inducer T cells by antigen and purified Ia incorporated into planar membranes

    SciTech Connect

    Quill, H.; Fox, B.; Carlson, L.; Pardoll, D.; Schwartz, R.H.

    1986-03-05

    Incubation of cytochrome c-specific E/sub ..beta..//sup k/E/sub ..cap alpha..//sup k/-containing planar membranes and an antigenic peptide analogue of moth cytochrome c resulted in a specific increase in cell volume of 40-50% as measured by Coulter Counter analysis. No change in cell volume was seen in the absence of antigen, or when A/sub ..beta..//sup k/A/sub ..cap alpha..//sup k/-planar membranes were used. T cell proliferation was never detected at any time from one to eight days after incubation with E/sub ..beta..//sup k/E/sub ..cap alpha..//sup k/-membranes at a wide range of antigen concentrations. Furthermore, only trace amounts of IL-2 were detected and no increase in IL-2 receptor expression was seen. IL-3 production, however, could be detected. T cells pre-incubated for one day with E/sub ..beta..//sup k/E/sub ..cap alpha..//sup k/-membranes plus antigen became non-responsive to subsequent normal stimulation with antigen and APC. Incorporation of /sup 3/H-thymidine was reduced by more than 90% and the production of both IL-2 and IL-3 was inhibited. Non-responsiveness persisted for at least eight days after exposure to E/sub ..beta..///sup k/E/sub ..cap alpha..//sup k/-membranes plus antigen. In contrast, T cells pre-incubated under control conditions remained fully responsive. These results demonstrate the specific induction of non-responsiveness in inducer T cells by antigen and purified E/sub ..beta..//sup k/E/sub ..cap alpha..//sup k/ in planar membranes.

  6. Responsiveness of Developing T Cells to IL-7 Signals Is Sustained by miR-17?92.

    PubMed

    Regelin, Malte; Blume, Jonas; Pommerencke, Jens; Vakilzadeh, Ramin; Witzlau, Katrin; ?yszkiewicz, Marcin; Zi?tara, Natalia; Saran, Namita; Schambach, Axel; Krueger, Andreas

    2015-11-15

    miRNAs regulate a large variety of developmental processes including development of the immune system. T cell development is tightly controlled through the interplay of transcriptional programs and cytokine-mediated signals. However, the role of individual miRNAs in this process remains largely elusive. In this study, we demonstrated that hematopoietic cell-specific loss of miR-17?92, a cluster of six miRNAs implicated in B and T lineage leukemogenesis, resulted in profound defects in T cell development both at the level of prethymic T cell progenitors as well as intrathymically. We identified reduced surface expression of IL-7R and concomitant limited responsiveness to IL-7 signals as a common mechanism resulting in reduced cell survival of common lymphoid progenitors and thymocytes at the double-negative to double-positive transition. In conclusion, we identified miR-17?92 as a critical modulator of multiple stages of T cell development. PMID:26475928

  7. Normal growth and development

    MedlinePLUS

    ... DIET Poor nutrition can cause problems with a child's intellectual development. A child with a poor diet may be ... care provider if you have concerns about your child's growth and development. Related topics include: Developmental milestones record - 4 months ...

  8. Effect of Cytomegalovirus Co-Infection on Normalization of Selected T-Cell Subsets in Children with Perinatally Acquired HIV Infection Treated with Combination Antiretroviral Therapy

    PubMed Central

    Kapetanovic, Suad; Aaron, Lisa; Montepiedra, Grace; Anthony, Patricia; Thuvamontolrat, Kasalyn; Pahwa, Savita; Burchett, Sandra; Weinberg, Adriana; Kovacs, Andrea

    2015-01-01

    Background We examined the effect of cytomegalovirus (CMV) co-infection and viremia on reconstitution of selected CD4+ and CD8+ T-cell subsets in perinatally HIV-infected (PHIV+) children ? 1-year old who participated in a partially randomized, open-label, 96-week combination antiretroviral therapy (cART)-algorithm study. Methods Participants were categorized as CMV-naïve, CMV-positive (CMV+) viremic, and CMV+ aviremic, based on blood, urine, or throat culture, CMV IgG and DNA polymerase chain reaction measured at baseline. At weeks 0, 12, 20 and 40, T-cell subsets including naïve (CD62L+CD45RA+; CD95-CD28+), activated (CD38+HLA-DR+) and terminally differentiated (CD62L-CD45RA+; CD95+CD28-) CD4+ and CD8+ T-cells were measured by flow cytometry. Results Of the 107 participants included in the analysis, 14% were CMV+ viremic; 49% CMV+ aviremic; 37% CMV-naïve. In longitudinal adjusted models, compared with CMV+ status, baseline CMV-naïve status was significantly associated with faster recovery of CD8+CD62L+CD45RA+% and CD8+CD95-CD28+% and faster decrease of CD8+CD95+CD28-%, independent of HIV VL response to treatment, cART regimen and baseline CD4%. Surprisingly, CMV status did not have a significant impact on longitudinal trends in CD8+CD38+HLA-DR+%. CMV status did not have a significant impact on any CD4+ T-cell subsets. Conclusions In this cohort of PHIV+ children, the normalization of naïve and terminally differentiated CD8+ T-cell subsets in response to cART was detrimentally affected by the presence of CMV co-infection. These findings may have implications for adjunctive treatment strategies targeting CMV co-infection in PHIV+ children, especially those that are now adults or reaching young adulthood and may have accelerated immunologic aging, increased opportunistic infections and aging diseases of the immune system. PMID:25794163

  9. Development of Guanidinium-Rich Protein Mimics for Efficient siRNA Delivery into Human T Cells.

    PubMed

    deRonde, Brittany M; Torres, Joe A; Minter, Lisa M; Tew, Gregory N

    2015-10-12

    RNA interference is gaining attention as a means to explore new molecular pathways and for its potential as a therapeutic; however, its application in immortal and primary T cells is limited due to challenges with efficient delivery in these cell types. Herein, we report the development of guanidinium-rich protein transduction domain mimics (PTDMs) based on a ring-opening metathesis polymerization scaffold that delivers siRNA into Jurkat T cells and human peripheral blood mononuclear cells (hPBMCs). Homopolymer and block copolymer PTDMs with varying numbers of guanidinium moieties were designed and tested to assess the effect cationic charge content and the addition of a segregated, hydrophobic block had on siRNA internalization and delivery. Internalization of fluorescently labeled siRNA into Jurkat T cells illustrates that the optimal cationic charge content, 40 charges per polymer, leads to higher efficiencies, with block copolymers outperforming their homopolymer counterparts. PTDMs also outperformed commercial reagents commonly used for siRNA delivery applications. Select PTDM candidates were further screened to assess the role the PTDM structure has on the delivery of biologically active siRNA into primary cells. Specifically, siRNA to hNOTCH1 was delivered to hPBMCs enabling 50-80% knockdown efficiencies, with longer PTDMs showing improved protein reduction. By evaluating the PTDM design parameters for siRNA delivery, more efficient PTDMs were discovered that improved delivery and gene (NOTCH) knockdown in T cells. Given the robust delivery of siRNA by these novel PTDMs, their development should aid in the exploration of T cell molecular pathways leading eventually to new therapeutics. PMID:26324222

  10. 77 FR 3482 - Prospective Grant of Exclusive License: Development of T Cell Receptors and Chimeric Antigen...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-24

    ... activate the CAR-expressing cell. Therapies utilizing these technologies involve isolating a cancer patient... on that specific patient's cancer cell. Afterwards, the engineered T cells from the patient are... Cell Receptors and Chimeric Antigen Receptors Into Therapeutics for Adoptive Transfer in Humans...

  11. Development of a Model System for Tick-Borne Flavivirus Persistence in HEK 293T Cells

    PubMed Central

    Mlera, Luwanika; Offerdahl, Danielle K.; Martens, Craig; Porcella, Stephen F.; Melik, Wessam

    2015-01-01

    ABSTRACT We devised a model system to study persistent infection by the tick-borne flavivirus Langat virus (LGTV) in 293T cells. Infection with a molecularly cloned LGTV strain produced an acute lytic crisis that left few surviving cells. The culture was repopulated by cells that were ~90% positive for LGTV E protein, thus initiating a persistent infection that was maintained for at least 35 weeks without additional lytic crises. Staining of cells for viral proteins and ultrastructural analysis revealed only minor differences from the acute phase of infection. Infectious LGTV decreased markedly over the study period, but the number of viral genomes remained relatively constant, suggesting the development of defective interfering particles (DIPs). Viral genome changes were investigated by RNA deep sequencing. At the initiation of persistent infection, levels of DIPs were below the limit of detection at a coverage depth of 11,288-fold, implying that DIPs are not required for initiation of persistence. However, after 15 passages, DIPs constituted approximately 34% of the total LGTV population (coverage of 1,293-fold). Furthermore, at this point, one specific DIP population predominated in which nucleotides 1058 to 2881 had been deleted. This defective genome specified an intact polyprotein that coded for a truncated fusion protein containing 28 N-terminal residues of E and 134 C-terminal residues of NS1. Such a fusion protein has not previously been described, and a possible function in persistent infection is uncertain. DIPs are not required for the initiation of persistent LGTV infection but may play a role in the maintenance of viral persistence. PMID:26045539

  12. Identification of stem cell transcriptional programs normally expressed in embryonic and neural stem cells in alloreactive CD8+ T cells mediating graft-versus-host disease

    PubMed Central

    Kato, Koji; Cui, Shuaiying; Kuick, Rork; Mineishi, Shin; Hexner, Elizabeth; Ferrara, James LM; Emerson, Stephen G.; Zhang, Yi

    2010-01-01

    A hallmark of graft-versus-host-disease (GVHD), a life-threatening complication after allogeneic hematopoietic stem cell transplantation, is the cytopathic injury of host tissues mediated by persistent alloreactive effector T cells (TE). However, the mechanisms that regulate the persistence of alloreactive TE during GVHD remain largely unknown. Using mouse GVHD models, we demonstrate that alloreactive CD8+ TE rapidly diminished in vivo when adoptively transferred into irradiated secondary congenic recipient mice. In contrast, although alloreactive CD8+ TE underwent massive apoptosis upon chronic exposure to alloantigens, they proliferated in vivo in secondary allogeneic recipients, persisted and caused severe GVHD. Thus, the continuous proliferation of alloreactive CD8+ TE, which is mediated by alloantigenic stimuli rather than homeostatic factors, is critical to maintaining their persistence. Gene expression profile analysis revealed that while alloreactive CD8+ TE increased the expression of genes associated with cell death, they activated a group of stem cell genes normally expressed in embryonic and neural stem cells. Most of these stem cell genes are associated with cell cycle regulation, DNA replication, chromatin modification and transcription. One of these genes, Ezh2, which encodes a chromatin modifying enzyme, was abundantly expressed in CD8+ TE. Silencing Ezh2 significantly reduced the proliferation of alloantigen-activated CD8+ T cells. Thus, these findings identify that a group of stem cell genes could play important roles in sustaining terminally differentiated alloreactive CD8+ TE and may be therapeutic targets for controlling GVHD. PMID:20116439

  13. An Excess of the Proinflammatory Cytokines IFN-? and IL-12 Impairs the Development of the Memory CD8+ T Cell Response to Chlamydia trachomatis.

    PubMed

    Zhang, Xuqing; Starnbach, Michael N

    2015-08-15

    The obligate intracellular bacterium Chlamydia trachomatis is the most common cause of bacterial sexually transmitted disease in the United States and the leading cause of preventable blindness worldwide. Transfer of cultured Chlamydia-specific CD8(+) T cells or vaccination with recombinant virus expressing an MHC I-restricted Chlamydia Ag confers protection, yet surprisingly a protective CD8(+) T cell response is not stimulated following natural infection. In this study, we demonstrate that the presence of excess IL-12 and IFN-? contributes to poor memory CD8(+) T cell development during C. trachomatis infection of mice. IL-12 is required for CD8(+) T cell expansion but drives effector CD8(+) T cells into a short-lived fate, whereas IFN-? signaling impairs the development of effector memory cells. We show that transient blockade of IL-12 and IFN-? during priming promotes the development of memory precursor effector CD8(+) T cells and increases the number of memory T cells that participate in the recall protection against subsequent infection. Overall, this study identifies key factors shaping memory development of Chlamydia-specific CD8(+) T cells that will inform future vaccine development against this and other pathogens. PMID:26179901

  14. The MAR-binding protein SATB1 orchestrates temporal and spatial expression of multiple genes during T-cell development

    SciTech Connect

    Alvarez, John D.; Yasui, Dag H.; Niida, Hiroyuki; Joh, Tadashi; Loh, Dennis Y.; Kowhi-Shigematsu, Terumi

    2000-02-24

    SATB1 is expressed primarily in thymocytes and can act as a transcriptional repressor. SATB1 binds in vivo to the matrix attachment regions (MARs) of DNA, which are implicated in the loop domain organization of chromatin. The role of MAR-binding proteins in specific cell lineages is unknown. We generated SATB1-null mice to determine how SATB1 functions in the T-cell lineage. SATB1-null mice are small in size, have disproportionately small thymi and spleens, and die at 3 weeks of age. At the cellular level, multiple defects in T-cell development were observed. Immature CD3-CD4-CD8 triple negative (TN) thymocytes were greatly reduced in number, and thymocyte development was blocked mainly at the DP stage. The few peripheral CD4{sup +} single positive (SP) cells underwent apoptosis and failed to proliferate in response to activating stimuli. At the molecular level, among 589 genes examined, at least 2% of genes including a proto-oncogene, cytokine receptor genes, and apoptosis-related genes were derepressed at inappropriate stages of T-cell development in SATB1-null mice. For example, IL-2R{alpha} and IL-7R{alpha} genes were ectopically transcribed in CD4{sup 4+}-CD{sup 8+} double positive (DP) thymocytes. SATB1 appears to orchestrate the temporal and spatial expression of genes during T-cell development, thereby ensuring the proper development of this lineage. Our data provide the first evidence that MAR-binding proteins can act as global regulators of cell function in specific cell lineages.

  15. T-cell receptor gene rearrangements as markers of lineage and clonality in T-cell neoplasms.

    PubMed Central

    Flug, F; Pelicci, P G; Bonetti, F; Knowles, D M; Dalla-Favera, R

    1985-01-01

    Ig gene rearrangements represent markers of lineage, clonality, and differentiation of B cells, allowing a molecular diagnosis and immunogenotypic classification of B-cell neoplasms. We sought to apply a similar approach to the study of T-cell populations by analyzing rearrangements of the T-cell receptor beta-chain (T beta) gene. Our analysis, by Southern blotting hybridization using T beta-specific probes of DNAs from polyclonal T cells and from 12 T-cell tumors, indicates that T beta gene rearrangement patterns can be used as markers of (i) lineage, allowing the identification of polyclonal T-cell populations, and (ii) clonality, allowing the detection of monoclonal T-cell tumors. In addition, our data indicate that T beta gene rearrangements represent early and general markers of T-cell differentiation since they are detectable in histologically different tumors at all stages of T-cell development. The ability to determine lineage, clonality, and stage of differentiation has significant implications for future experimental and clinical studies on normal and neoplastic T cells. Images PMID:2987928

  16. Nucleoprotein structure of the CD4 locus: Implications for the mechanisms underlying CD4 regulation during T cell development

    PubMed Central

    Yu, Ming; Wan, Mimi; Zhang, Jianmin; Wu, Jie; Khatri, Rohini; Chi, Tian

    2008-01-01

    The CD4 gene is regulated in a stage-specific manner during T cell development, being repressed in CD4?CD8? double-negative (DN) and CD8 cells, but expressed in CD4+CD8+ double-positive (DP) and CD4 cells. Furthermore, the expression/repression pattern is reversible in developing (DN and DP) thymocytes, but irreversible in mature (CD4 and CD8) T cells. Here, we explored the molecular mechanisms underlying this complex mode of regulation by examining the nucleoprotein structure of the CD4 locus throughout T cell development and in DN cells lacking the CD4 silencer. In DN cells, the CD4 enhancer is preloaded with multiple transcription activators, but p300 recruitment is impaired by the silencer that is associated with the repressor Runx1. DP cells achieve high-level CD4 expression via a combination of CD4 derepression and true activation, but Runx1 remains bound to the silencer that retains an open chromatin configuration. In CD4 cells, Runx1 dissociates from the silencer that has become less accessible, and CD4 transcription appears to be achieved via a mechanism distinct from that operating in DP cells. In CD8 cells, the CD4 promoter becomes incorporated into heterochromatin-like structure. Our data shed light on the molecular basis of CD4 regulation and provide a conceptual framework for understanding how the same regulatory elements can mediate both reversible and irreversible CD4 regulation. PMID:18322012

  17. Immature myeloid cells directly contribute to skin tumor development by recruiting IL-17–producing CD4+ T cells

    PubMed Central

    Ortiz, Myrna L.; Kumar, Vinit; Martner, Anna; Mony, Sridevi; Donthireddy, Laxminarasimha; Condamine, Thomas; Seykora, John; Knight, Stella C.; Malietzis, George; Lee, Gui Han; Moorghen, Morgan; Lenox, Brianna; Luetteke, Noreen; Celis, Esteban

    2015-01-01

    Evidence links chronic inflammation with cancer, but cellular mechanisms involved in this process remain unclear. We have demonstrated that in humans, inflammatory conditions that predispose to development of skin and colon tumors are associated with accumulation in tissues of CD33+S100A9+ cells, the phenotype typical for myeloid-derived suppressor cells in cancer or immature myeloid cells (IMCs) in tumor-free hosts. To identify the direct role of these cells in tumor development, we used S100A9 transgenic mice to create the conditions for topical accumulation of these cells in the skin in the absence of infection or tissue damage. These mice demonstrated accumulation of granulocytic IMCs in the skin upon topical application of 12-O-tetradecanoylphorbol-13-acetate (TPA), resulting in a dramatic increase in the formation of papillomas during epidermal carcinogenesis. The effect of IMCs on tumorigenesis was not associated with immune suppression, but with CCL4 (chemokine [C-C motif] ligand 4)-mediated recruitment of IL-17–producing CD4+ T cells. This chemokine was released by activated IMCs. Elimination of CD4+ T cells or blockade of CCL4 or IL-17 abrogated the increase in tumor formation caused by myeloid cells. Thus, this study implicates accumulation of IMCs as an initial step in facilitation of tumor formation, followed by the recruitment of CD4+ T cells. PMID:25667306

  18. mTOR complex 2 modulates ??T-cell receptor processing and surface expression during thymocyte development 1

    PubMed Central

    Chou, Po-Chien; Oh, Won Jun; Wu, Chang-Chih; Moloughney, Joseph; Rüegg, Markus; Hall, Michael N.; Jacinto, Estela; Werlen, Guy

    2014-01-01

    Summary An efficient immune response relies on the presence of T-cells expressing a functional T-cell receptor (TCR). While the mechanisms generating TCR diversity for antigenic recognition are well defined, what controls its surface expression is less known. Here we found that deletion of the mTORC2 component rictor at early stages of T-cell development led to aberrant maturation and increased proteasomal degradation of nascent TCR. While CD127 expression became elevated, the levels of TCR as well as CD4, CD8, CD69, Notch and CD147 were significantly attenuated on the surface of rictor-deficient thymocytes. Diminished expression of these receptors led to suboptimal signaling, partial DN4 proliferation and DP activation as well as developmental blocks at the double-negative 3 and CD8-ISP stages. Since CD147 glycosylation was also defective in SIN1-deficient fibroblasts, our findings suggest that mTORC2 is involved in the co/post-translational processing of membrane receptors. Thus, mTORC2 impacts development via regulation of the quantity and quality of receptors important for cell differentiation. PMID:24981454

  19. Influence of HIV and HCV on T cell antigen presentation and challenges in the development of vaccines

    PubMed Central

    John, Mina; Gaudieri, Silvana

    2014-01-01

    Some of the central challenges for developing effective vaccines against HIV and hepatitis C virus (HCV) are similar. Both infections are caused by small, highly mutable, rapidly replicating RNA viruses with the ability to establish long-term chronic pathogenic infection in human hosts. HIV has caused 60 million infections globally and HCV 180 million and both viruses may co-exist among certain populations by virtue of common blood-borne, sexual, or vertical transmission. Persistence of both pathogens is achieved by evasion of intrinsic, innate, and adaptive immune defenses but with some distinct mechanisms reflecting their differences in evolutionary history, replication characteristics, cell tropism, and visibility to mucosal versus systemic and hepatic immune responses. A potent and durable antibody and T cell response is a likely requirement of future HIV and HCV vaccines. Perhaps the single biggest difference between the two vaccine design challenges is that in HCV, a natural model of protective immunity can be found in those who resolve acute infection spontaneously. Such spontaneous resolvers exhibit durable and functional CD4+ and CD8+ T cell responses (Diepolder et al., 1995; Cooper et al., 1999; Thimme et al., 2001; Grakoui et al., 2003; Lauer et al., 2004; Schulze Zur Wiesch et al., 2012). However, frequent re-infection suggests partial or lack of protective immunity against heterologous HCV strains, possibly indicative of the degree of genetic diversity of circulating HCV genotypes and subtypes. There is no natural model of protective immunity in HIV, however, studies of “elite controllers,” or individuals who have durably suppressed levels of plasma HIV RNA without antiretroviral therapy, has provided the strongest evidence for CD8+ T cell responses in controlling viremia and limiting reservoir burden in established infection. Here we compare and contrast the specific mechanisms of immune evasion used by HIV and HCV, which subvert adaptive human leukocyte antigen (HLA)-restricted T cell immunity in natural infection, and the challenges these pose for designing effective preventative or therapeutic vaccines. PMID:25352836

  20. Spontaneous Intestinal Tumorigenesis in Apc/Min+ Mice Requires Altered T Cell Development with IL-17A

    PubMed Central

    Chae, Wook-Jin; Bothwell, Alfred L. M.

    2015-01-01

    The control of inflammatory diseases requires functional regulatory T cells (Tregs) with significant Gata-3 expression. Here we address the inhibitory role of Tregs on intestinal tumorigenesis in the Apc/Min+ mouse model that resembles human familial adenomatous polyposis (FAP). Apc/Min+ mice had a markedly increased frequency of Foxp3+ Tregs and yet decreased Gata-3 expression in the lamina propria. To address the role of heterozygous Apc gene mutation in Tregs, we generated Foxp3-Cre, Apcflox/+ mice. Tregs from these mice effectively inhibited tumorigenesis comparable to wild type Tregs after adoptive transfer into Apc/Min+ mice, demonstrating that the heterozygous Apc gene mutation in Tregs does not induce the loss of control over tumor microenvironment. Adoptive transfer of in vitro generated Apc/Min+ iTregs (inducible Tregs) failed to inhibit intestinal tumorigenesis, suggesting that naïve CD4 T cells generated from Apc/Min+ mice thymus were impaired. We also showed that adoptively transferred IL-17A-deficient Apc/Min+ Tregs inhibited tumor growth, suggesting that IL-17A was critical to impair the tumor regression function of Apc/Min+ Tregs. Taken together, our results suggest that both T cell development in a functional thymus and IL-17A control the ability of Treg to inhibit intestinal tumorigenesis in Apc/Min+ mice. PMID:26146642

  1. Unexpected Role for the B cell-specific Src Family Kinase Blk in the Development of IL-17-Producing ?? T Cells

    PubMed Central

    Laird, Renee M.; Laky, Karen; Hayes, Sandra M.

    2010-01-01

    The Ag receptors on ?? and ?? T cells differ not only in the nature of the ligands that they recognize but also in their signaling potential. We hypothesized that the differences in ??- and ??TCR signal transduction were due to differences in the intracellular signaling pathways coupled to these two TCRs. To investigate this, we employed transcriptional profiling to identify genes encoding signaling molecules that are differentially expressed in mature ?? and ?? T cell populations. Unexpectedly, we found that B lymphoid kinase (Blk), a Src family kinase expressed primarily in B cells, is expressed in ?? T cells but not in ?? T cells. Analysis of Blk-deficient mice revealed that Blk is required for the development of IL-17-producing ?? T cells. Furthermore, Blk is expressed in lymphoid precursors and, in this capacity, plays a role in regulating thymus cellularity during ontogeny. PMID:20974990

  2. KAP1 regulates gene networks controlling T-cell development and responsiveness.

    PubMed

    Santoni de Sio, Francesca R; Barde, Isabelle; Offner, Sandra; Kapopoulou, Adamandia; Corsinotti, Andrea; Bojkowska, Karolina; Genolet, Raphaël; Thomas, James H; Luescher, Immanuel F; Pinschewer, Daniel; Harris, Nicola; Trono, Didier

    2012-11-01

    Chromatin remodeling at specific genomic loci controls lymphoid differentiation. Here, we investigated the role played in this process by Kruppel-associated box (KRAB)-associated protein 1 (KAP1), the universal cofactor of KRAB-zinc finger proteins (ZFPs), a tetrapod-restricted family of transcriptional repressors. T-cell-specific Kap1-deleted mice displayed a significant expansion of immature thymocytes, imbalances in CD4(+)/CD8(+) cell ratios, and altered responses to TCR and TGF? stimulation when compared to littermate KAP1 control mice. Transcriptome and chromatin studies revealed that KAP1 binds T-cell-specific cis-acting regulatory elements marked by the H3K9me3 repressive mark and enriched in Ikaros/NuRD complexes. Also, KAP1 directly controls the expression of several genes involved in TCR and cytokine signaling. Among these, regulation of FoxO1 seems to play a major role in this system. Likely responsible for tethering KAP1 to at least part of its genomic targets, a small number of KRAB-ZFPs are selectively expressed in T-lymphoid cells. These results reveal the so far unsuspected yet important role of KAP1-mediated epigenetic regulation in T-lymphocyte differentiation and activation. PMID:22872677

  3. T cell migration during development: homing is not related to TCR V beta 1 repertoire selection.

    PubMed Central

    Dunon, D; Schwager, J; Dangy, J P; Cooper, M D; Imhof, B A

    1994-01-01

    T cell precursors enter the chick thymus in three waves during embryonic life. Each wave of thymocyte precursors colonizing the thymus gave rise to a similar TCR V beta repertoire in thymus, spleen and intestine both in terms of V beta 1 and J beta usage as well as in the length of V beta-D beta-J beta junctions. Seventeen V beta 1s were utilized, and a new J beta segment was found. In the progeny of the third wave, more nucleotides were deleted at the 5' end of the J beta segment, but the overall size of the CDR3 was conserved by a concomitant increase of N nucleotide addition at the V beta-D beta-J beta junctions during rearrangement. This CDR3 modification was observed in the spleen but not in the intestine, implying that progeny of the third wave migrate preferentially to the spleen, a possibility that was confirmed by adoptive cell transfers into congenic chickens. Very low frequencies of non-productive rearrangements in the intestine suggested that negative selection may occur in this organ. The present analysis indicates that V beta 1+ T cells in spleen and intestine are primarily of thymic origin, this colonization of both organs occurs in waves and is not characterized by preselection of the TCR V beta 1 repertoire. Images PMID:8112295

  4. Molecular profiling of CD8 T cells in autochthonous melanoma identifies Maf as driver of exhaustion.

    PubMed

    Giordano, Marilyn; Henin, Coralie; Maurizio, Julien; Imbratta, Claire; Bourdely, Pierre; Buferne, Michel; Baitsch, Lukas; Vanhille, Laurent; Sieweke, Michael H; Speiser, Daniel E; Auphan-Anezin, Nathalie; Schmitt-Verhulst, Anne-Marie; Verdeil, Grégory

    2015-08-01

    T cells infiltrating neoplasms express surface molecules typical of chronically virus-stimulated T cells, often termed "exhausted" T cells. We compared the transcriptome of "exhausted" CD8 T cells infiltrating autochthonous melanomas to those of naïve and acutely stimulated CD8 T cells. Despite strong similarities between transcriptional signatures of tumor- and virus-induced exhausted CD8 T cells, notable differences appeared. Among transcriptional regulators, Nr4a2 and Maf were highly overexpressed in tumor-exhausted T cells and significantly upregulated in CD8 T cells from human melanoma metastases. Transduction of murine tumor-specific CD8 T cells to express Maf partially reproduced the transcriptional program associated with tumor-induced exhaustion. Upon adoptive transfer, the transduced cells showed normal homeostasis but failed to accumulate in tumor-bearing hosts and developed defective anti-tumor effector responses. We further identified TGF? and IL-6 as main inducers of Maf expression in CD8 T cells and showed that Maf-deleted tumor-specific CD8 T cells were much more potent to restrain tumor growth in vivo. Therefore, the melanoma microenvironment contributes to skewing of CD8 T cell differentiation programs, in part by TGF?/IL-6-mediated induction of Maf. PMID:26139534

  5. Id3 and Id2 act as a dual safety mechanism in regulating the development and population size of innate-like ?? T cells

    PubMed Central

    Dai, Meifang; Zhuang, Yuan

    2014-01-01

    The innate-like T cells expressing V?1.1 and V?6.3 represent a unique T cell lineage sharing features with both the ?? T and the invariant NKT cells. The population size of V?1.1+V?6.3+ T cells is tightly controlled and usually contributes to a very small proportion of thymic output, but the underlying mechanism remains enigmatic. Deletion of Id3, an inhibitor of E-protein transcription factors, can induce an expansion of the V?1.1+V?6.3+ T cell population. This phenotype is much stronger on the C57Bl/6 background than on the 129/sv background. Using quantitative trait linkage analysis, we identified Id2, a homologue of Id3, to be the major modifier of Id3 in limiting V?1.1+V?6.3+ T cell expansion. The V?1.1+V?6.3+ phenotype is attributed to an intrinsic weakness of Id2 transcription from Id2 C57Bl/6 allele, leading to an overall reduced dosage of Id proteins. However, complete removal of both Id2 and Id3 genes in developing T cells suppressed the expansion of V?1.1+V?6.3+ T cells due to decreased proliferation and increased cell death. We showed that conditional knockout of Id2 alone is sufficient to promote a moderate expansion of ?? T cells. These regulatory effects of Id2 and Id3 on V?1.1+V?6.3+ T cells are mediated by titration of E protein activity, since removing one or more copies of E protein genes can restore V?1.1+V?6.3+ T cell expansion in Id2 and Id3 double conditional knockout mice. Our data indicated that Id2 and Id3 collaboratively control survival and expansion of the ?? lineage through modulating a proper threshold of E-proteins. PMID:24379125

  6. Activated regulatory T cell regulates neural stem cell proliferation in the subventricular zone of normal and ischemic mouse brain through interleukin 10

    PubMed Central

    Wang, Jixian; Xie, Luokun; Yang, Chenqi; Ren, Changhong; Zhou, Kaijing; Wang, Brian; Zhang, Zhijun; Wang, Yongting; Jin, Kunlin; Yang, Guo-Yuan

    2015-01-01

    Recent studies have demonstrated that the depletion of Regulatory T cells (Tregs) inhibits neural progenitor cell migration after brain ischemia. However, whether Tregs affect neural stem/progenitor cell proliferation is unclear. We explored the effect of Tregs on neurogenesis in the subventricular zone (SVZ) after ischemia. Tregs were isolated and activated in vitro. Adult male C57BL/6 mice underwent 60 min transient middle cerebral artery occlusion (tMCAO). Then Tregs (1 × 105) were injected into the left lateral ventricle (LV) of normal and ischemic mouse brain. Neurogenesis was determined by immunostaining. The mechanism was examined by inhibiting interleukin 10 (IL-10) and transforming growth factor (TGF-?) signaling. We found that the number of BrdU+ cells in the SVZ was significantly increased in the activated Tregs-treated mice. Double immunostaining showed that these BrdU+ cells expressed Mash1. Blocking IL-10 reduced the number of Mash1+/BrdU+ cells, but increased the amount of GFAP+/BrdU+ cells. Here, we conclude that activated Tregs enhanced neural stem cell (NSC) proliferation in the SVZ of normal and ischemic mice; blockage of IL-10 abolished Tregs-mediated NSC proliferation in vivo and in vitro. Our results suggest that activated Tregs promoted NSC proliferation via IL-10, which provides a new therapeutic approach for ischemic stroke. PMID:26441532

  7. New developments in the treatment of peripheral T-cell lymphoma – role of Belinostat

    PubMed Central

    Reimer, Peter

    2015-01-01

    Peripheral T-cell lymphomas (PTCL) represent a heterogeneous group of rare malignancies that with the exception of anaplastic lymphoma kinase expressing anaplastic large cell lymphoma, share a poor outcome after standard (eg, anthracycline-based) chemotherapy. Most patients are either refractory to initial therapy or eventually relapse. Randomized studies for relapsed/refractory PTCL are not available, however, recently published data show that conventional chemotherapy has very limited efficacy in the salvage setting. Thus, novel drugs are urgently needed to improve the outcome in this setting. Belinostat, a pan-histone deacetylase inhibitor, has demonstrated meaningful efficacy and a favorable toxicity profile in two single-arm Phase II trials on 153 patients with relapsed/refractory PTCL. The conclusive results led to an accelerated approval by the US Food and Drug Administration. The present review summarizes the clinical data available for belinostat, its current role, and future perspectives. PMID:26082661

  8. Age-related development and tissue distribution of T cell markers (CD4 and CD8a) in Chinese goose.

    PubMed

    Chen, Shun; Zhou, Qin; Cheng, Beibei; Yan, Bing; Yan, Xiaoling; Zhao, Qiurong; Wang, Mingshu; Jia, Renyong; Zhu, Dekang; Liu, Mafeng; Chen, Xiaoyue; Cheng, Anchun

    2015-06-01

    Aquatic birds play n critical role in the transmission and dissemination of many important pathogens such as avian influenza virus. The cell-mediated immunity is very important in eliminating the intracellular antigens. Expression of CD4 and CD8 on T cell surface is essential for cell-mediated immune defence and T-cell development. However, the ontogeny of T lymphocytes in waterfowl is scarce and fragmentary. To address these questions, here we report the development and tissues distribution of CD4 and CD8? in goose embryo, gosling and goose by immunocytochemistry assay using monoclonal antibodies. Moreover, the age-related mRNA level of goose CD4 and CD8? in different immune tissues were study by real time quantitative PCR. Our results suggested that the high expression of CD4 and CD8? were readily found in thymus, which peaked at the first week post-hatch. And the highest expression level of CD4 and CD8? were detected in bursa of Fabricius, caecal tonsils, spleen and intestine at the second week, after that the expression level were gradually decreased. Interestingly, the remarkably high expression of CD4 and CD8? in Harderian gland were detected at the first week, which is about hundreds times more than that in other tissues. Our findings demonstrated that the development and the distribution of CD4 and CD8? are partly changed in an age-related way. Moreover, the histological morphogenesis of immune tissues were also discussed. Our results may shed lights on the better understand of T-cell mediate immunity in goose. PMID:25616911

  9. Pak2 Links TCR Signaling Strength to the Development of Regulatory T Cells and Maintains Peripheral Tolerance.

    PubMed

    O'Hagan, Kyle Leonard; Choi, Jinyong; Pryshchep, Olga; Chernoff, Jonathan; Phee, Hyewon

    2015-08-15

    Although significant effort has been devoted to understanding the thymic development of Foxp3(+) regulatory T cells (Tregs), the precise signaling pathways that govern their lineage commitment still remain enigmatic. Our findings show a novel role for the actin cytoskeletal remodeling protein, p21-activated kinase 2 (Pak2), in Treg development and homeostasis. The absence of Pak2 in T cells resulted in a marked reduction in both thymus- and peripherally derived Tregs, accompanied by the development of spontaneous colitis in Pak2-deficient mice. Additionally, Pak2 was required for the proper differentiation of in vitro-induced Tregs as well as maintenance of Tregs. Interestingly, Pak2 was necessary for generating the high-affinity TCR- and IL-2-mediated signals that are required by developing Tregs for their lineage commitment. These findings provide novel insight into how developing thymocytes translate lineage-specific high-affinity TCR signals to adopt the Treg fate, and they further posit Pak2 as an essential regulator for this process. PMID:26157175

  10. Bcl11b prevents the intrathymic development of innate CD8 T cells in a cell intrinsic manner.

    PubMed

    Hirose, Satoshi; Touma, Maki; Go, Rieka; Katsuragi, Yoshinori; Sakuraba, Yoshiyuki; Gondo, Yoichi; Abe, Manabu; Sakimura, Kenji; Mishima, Yukio; Kominami, Ryo

    2015-04-01

    If Bcl11b activity is compromised, CD4(+)CD8(+) double-positive (DP) thymocytes produce a greatly increased fraction of innate CD8(+) single-positive (SP) cells highly producing IFN-?, which are also increased in mice deficient of genes such as Itk, Id3 and NF-?B1 that affect TCR signaling. Of interest, the increase in the former two is due to the bystander effect of IL-4 that is secreted by promyelocytic leukemia zinc finger-expressing NKT and ??T cells whereas the increase in the latter is cell intrinsic. Bcl11b zinc-finger proteins play key roles in T cell development and T cell-mediated immune response likely through TCR signaling. We examined thymocytes at and after the DP stage in Bcl11b (F/S826G) CD4cre, Bcl11b (F/+) CD4cre and Bcl11b (+/S826G) mice, carrying the allele that substituted serine for glycine at the position of 826. Here we show that Bcl11b impairment leads to an increase in the population of TCR??(high)CD44(high)CD122(high) innate CD8SP thymocytes, together with two different developmental abnormalities: impaired positive and negative selection accompanying a reduction in the number of CD8SP cells, and developmental arrest of NKT cells at multiple steps. The innate CD8SP thymocytes express Eomes and secrete IFN-? after stimulation with PMA and ionomycin, and in this case their increase is not due to a bystander effect of IL-4 but cell intrinsic. Those results indicate that Bcl11b regulates development of different thymocyte subsets at multiple stages and prevents an excess of innate CD8SP thymocytes. PMID:25422283

  11. Thymic Damage, Impaired Negative Selection, and Development of Chronic Graft-versus-Host Disease Caused by Donor CD4+ and CD8+ T Cells

    PubMed Central

    Wu, Tao; Young, James S.; Johnston, Heather; Ni, Xiong; Deng, Ruishu; Racine, Jeremy; Wang, Miao; Wang, Audrey; Todorov, Ivan; Wang, Jianmin; Zeng, Defu

    2013-01-01

    Prevention of chronic graft-versus-host disease (cGVHD) remains a major challenge in allogeneic hematopoietic cell transplantation (HCT), due to limited understanding of cGVHD pathogenesis and lack of appropriate animal models. Here, we report that, in classical acute GVHD models with C57BL/6 donors and MHC-mismatched BALB/c recipients and with C3H.SW donors and MHC-matched C57BL/6 recipients, GVHD recipients surviving for more than 60 days after HCT developed cGVHD characterized by cutaneous fibrosis, tissue damage in the salivary gland and the presence of serum autoantibodies. Donor CD8+ T cells were more potent than CD4+ T cells for inducing cGVHD. The recipient thymus and de novo-generated, donor-derived CD4+ T cells were required for induction of cGVHD by donor CD8+ T cells but not by donor CD4+ T cells. Donor CD8+ T cells preferentially damaged recipient medullary thymic epithelial cells and impaired negative selection, resulting in production of autoreactive CD4+ T cells that perpetuated damage to the thymus and augmented the development of cGVHD. Short-term anti-CD4 monoclonal antibody treatment early after HCT enabled recovery from thymic damage and prevented cGVHD. These results demonstrate that donor CD8+ T cells cause cGVHD solely through thymic-dependent mechanisms, while CD4+ T cells can cause cGVHD through either thymic-dependent or independent mechanisms. PMID:23709681

  12. Rap1b Regulates B Cell Development, Homing, and T Cell-Dependent Humoral Immunity1

    PubMed Central

    Chu, Haiyan; Awasthi, Aradhana; White, Gilbert C.; Chrzanowska-Wodnicka, Magdalena; Malarkannan, Subramaniam

    2015-01-01

    Rap1 is a small GTPase that belongs to Ras superfamily. This ubiquitously expressed GTPase is a key regulator of integrin functions. Rap1 exists in two isoforms: Rap1a and Rap1b. Although Rap1 has been extensively studied, its isoform-specific functions in B cells have not been elucidated. In this study, using gene knockout mice, we show that Rap1b is the dominant isoform in B cells. Lack of Rap1b significantly reduced the absolute number of B220+IgM? pro/pre-B cells and B220+IgM+ immature B cells in bone marrow. In vitro culture of bone marrow-derived Rap1b?/? pro/pre-B cells with IL-7 showed similar proliferation levels but reduced adhesion to stromal cell line compared with wild type. Rap1b?/? mice displayed reduced splenic marginal zone (MZ) B cells, and increased newly forming B cells, whereas the number of follicular B cells was normal. Functionally, Rap1b?/? mice showed reduced T-dependent but normal T-independent humoral responses. B cells from Rap1b?/? mice showed reduced migration to SDF-1, CXCL13 and in vivo homing to lymph nodes. MZ B cells showed reduced sphingosine-1-phosphate-induced migration and adhesion to ICAM-1. However, absence of Rap1b did not affect splenic B cell proliferation, BCR-mediated activation of Erk1/2, p38 MAPKs, and AKT. Thus, Rap1b is crucial for early B cell development, MZ B cell homeostasis and T-dependent humoral immunity. PMID:18714009

  13. Strategy escalation: an emerging paradigm for safe clinical development of T cell gene therapies.

    PubMed

    Junghans, Richard Paul

    2010-01-01

    Gene therapy techniques are being applied to modify T cells with chimeric antigen receptors (CARs) for therapeutic ends. The versatility of this platform has spawned multiple options for their application with new permutations in strategies continually being invented, a testimony to the creative energies of many investigators. The field is rapidly expanding with immense potential for impact against diverse cancers. But this rapid expansion, like the Big Bang, comes with a somewhat chaotic evolution of its therapeutic universe that can also be dangerous, as seen by recently publicized deaths. Time-honored methods for new drug testing embodied in Dose Escalation that were suitable for traditional inert agents are now inadequate for these novel "living drugs". In the following, I propose an approach to escalating risk for patient exposures with these new immuno-gene therapy agents, termed Strategy Escalation, that accounts for the molecular and biological features of the modified cells and the methods of their administration. This proposal is offered not as a prescriptive but as a discussion framework that investigators may wish to consider in configuring their intended clinical applications. PMID:20537174

  14. Molecular Evidence for a Thymus-Independent Partial T Cell Development in a FOXN1?/? Athymic Human Fetus

    PubMed Central

    Fusco, Anna; Panico, Luigi; Gorrese, Marisa; Bianchino, Gabriella; Barone, Maria V.; Grieco, Vitina; Vitiello, Laura; D’Assante, Roberta; Romano, Rosa; Palamaro, Loredana; Scalia, Giulia; Vecchio, Luigi Del; Pignata, Claudio

    2013-01-01

    The thymus is the primary organ able to support T cell ontogeny, abrogated in FOXN1?/? human athymia. Although evidence indicates that in animal models T lymphocytes may differentiate at extrathymic sites, whether this process is really thymus-independent has still to be clarified. In an athymic FOXN1?/? fetus, in which we previously described a total blockage of CD4+ and partial blockage of CD8+ cell development, we investigated whether intestine could play a role as extrathymic site of T-lymphopoiesis in humans. We document the presence of few extrathymically developed T lymphocytes and the presence in the intestine of CD3+ and CD8+, but not of CD4+ cells, a few of them exhibiting a CD45RA+ naïve phenotype. The expression of CD3??pT?, RAG1 and RAG2 transcripts in the intestine and TCR gene rearrangement was also documented, thus indicating that in humans the partial T cell ontogeny occurring at extrathymic sites is a thymus- and FOXN1-independent process. PMID:24349129

  15. The Role of B Cells in the Development of CD4 Effector T Cells during a Polarized Th2 Immune Response1

    PubMed Central

    Liu, Qian; Liu, Zhugong; Rozo, Cristina T.; Hamed, Hossein A.; Alem, Farhang; Urban, Joseph F.; Gause, William C.

    2008-01-01

    Previous studies have suggested that B cells promote Th2 cell development by inhibiting Th1 cell differentiation. To examine whether B cells are directly required for the development of IL-4-producing T cells in the lymph node during a highly polarized Th2 response, B cell-deficient and wild-type mice were inoculated with the nematode parasite, Nippostrongylus brasiliensis. On day 7, in the absence of increased IFN-?, IL-4 protein and gene expression from CD4 T cells in the draining lymph nodes were markedly reduced in B cell-deficient mice and could not be restored by multiple immunizations. Using a DO11.10 T cell adoptive transfer system, OVA-specific T cell IL-4 production and cell cycle progression, but not cell surface expression of early activation markers, were impaired in B cell-deficient recipient mice following immunization with N. brasiliensis plus OVA. Laser capture microdissection and immunofluorescent staining showed that pronounced IL-4 mRNA and protein secretion by donor DO11.10 T cells first occurred in the T cell:B cell zone of the lymph node shortly after inoculation of IL-4?/? recipients, suggesting that this microenvironment is critical for initial Th2 cell development. Reconstitution of B cell-deficient mice with wild-type naive B cells, or IL-4?/? B cells, substantially restored Ag-specific T cell IL-4 production. However, reconstitution with B7-1/B7-2-deficient B cells failed to rescue the IL-4-producing DO11.10 T cells. These results suggest that B cells, expressing B7 costimulatory molecules, are required in the absence of an underlying IFN-?-mediated response for the development of a polarized primary Ag-specific Th2 response in vivo. PMID:17785819

  16. Faster T-cell development following gene therapy compared with haploidentical HSCT in the treatment of SCID-X1.

    PubMed

    Touzot, Fabien; Moshous, Despina; Creidy, Rita; Neven, Bénédicte; Frange, Pierre; Cros, Guilhem; Caccavelli, Laure; Blondeau, Johanna; Magnani, Alessandra; Luby, Jean-Marc; Ternaux, Brigitte; Picard, Capucine; Blanche, Stéphane; Fischer, Alain; Hacein-Bey-Abina, Salima; Cavazzana, Marina

    2015-06-01

    During the last decade, gene therapy via ex vivo gene transfer into autologous hematopoietic stem cells has emerged as a convincing therapy for severe combined immunodeficiency caused by ILR2G mutation (SCID-X1) despite the occurrence of genotoxicity caused by the integration of first-generation retroviral vectors. However, the place of gene therapy among the therapeutic armamentarium remains to be defined. We retrospectively analyze and compare clinical outcomes and immune reconstitution in 13 consecutive SCID-X1 patients having undergone haploidentical hematopoietic stem cell transplantation (HSCT) and 14 SCID-X1 patients treated with gene therapy over the same period at a single center level: the Necker Children's Hospital (Paris, France). Our results show a clear advantage in terms of T-cell development of gene therapy over HSCT with a mismatched donor. Patients treated with gene therapy display a faster T-cell reconstitution and a better long-term thymic output. Interestingly, this advantage of gene therapy vs haploidentical HSCT seems to be independent of the existence of clinical graft-versus-host disease in the latter condition. If data of safety are confirmed over the long term, gene therapy for SCID-X1 appears to be an equal, if not superior, alternative to haploidentical HSCT. PMID:25869287

  17. The bone marrow of myeloma patients is steadily inhabited by a normal-sized pool of functional regulatory T cells irrespectiveof the disease status.

    PubMed

    Foglietta, Myriam; Castella, Barbara; Mariani, Sara; Coscia, Marta; Godio, Laura; Ferracini, Riccardo; Ruggeri, Marina; Muccio, Vittorio; Omedé, Paola; Palumbo, Antonio; Boccadoro, Mario; Massaia, Massimo

    2014-10-01

    Conflicting data have been reported about the frequency and function of regulatory T cells in multiple myeloma. Most studies have investigated peripheral blood rather than bone marrow Tregs and side-by-side comparisons with bone marrow from healthy donors have still not been made. In this study, we show that regulatory T-cells total count, subset distribution, and expression of chemokine receptors are similar in the bone marrow of myeloma patients and healthy donors. Regulatory T cells are not recruited by myeloma cells in the bone marrow and their counts are unaffected by the tumor burden and the disease status. The diversity of T-cell receptor repertoire is highly preserved ensuring broad reactivity and effective suppressor function. Our results indicate that regulatory T cells may not be the main players of immunological tolerance to myeloma cells under base-line conditions, but their fully preserved immune competence may promote their inadvertent activation and blunt T-cell driven anti-myeloma immune interventions even after myeloma cells have successfully been cleared by chemotherapy. PMID:24972771

  18. Changes in thymic export of gamma delta and alpha beta T cells during fetal and postnatal development.

    PubMed

    Witherden, D A; Kimpton, W G; Abernethy, N J; Cahill, R N

    1994-10-01

    The thymus plays an essential role in the generation and selection of T cells and exports approximately 0.5-1% of thymocytes per day in young animals and considerably fewer in older animals. To date there have been no studies directly examining fetal thymic export in any species. Using the technique of intrathymic injection of fluorescein isothiocyanate, followed by an assay for green fluorescent cells in the periphery and for the expression of cell surface antigens on these cells, we have compared directly the export of T cells from the fetal and postnatal ovine thymus. While the thymus exports both alpha beta and gamma delta T cells, our results demonstrate that the proportion of thymic gamma delta T cells that are exported per day is much higher than that of thymic alpha beta T cells. Moreover, the export rate of gamma delta T cells increased from approximately 1 in every 60 gamma delta thymocytes per day emigrating from the fetal thymus to 1 in every 20 from the postnatal thymus. In addition, we identify a population of CD5+CD4-CD8-gamma delta-. T cells emigrating from the fetal thymus but greatly reduced among thymic emigrants after birth. These findings have several implications regarding the mechanisms and control of selection of both gamma delta and alpha beta T cells. PMID:7925561

  19. 78 FR 69429 - Prospective Grant of Exclusive License: The Development of Modified T-cells for the Treatment of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-19

    ... Modified T-cells for the Treatment of Multiple Myeloma AGENCY: National Institutes of Health, HHS. ACTION.../ 622,6008 entitled, ``Chimeric Antigen Receptors Targeting B-cell Maturation Antigen'' . The patent... human T-cells directed against B-cell Maturation Antigen (BCMA) for the treatment of multiple...

  20. Dynamic regulation of notch 1 and notch 2 surface expression during T cell development and activation revealed by novel monoclonal antibodies.

    PubMed

    Fiorini, Emma; Merck, Estelle; Wilson, Anne; Ferrero, Isabel; Jiang, Wei; Koch, Ute; Auderset, Floriane; Laurenti, Elisa; Tacchini-Cottier, Fabienne; Pierres, Michel; Radtke, Freddy; Luther, Sanjiv A; Macdonald, H Robson

    2009-12-01

    It is well established that Notch signaling plays a critical role at multiple stages of T cell development and activation. However, detailed analysis of the cellular and molecular events associated with Notch signaling in T cells is hampered by the lack of reagents that can unambiguously measure cell surface Notch receptor expression. Using novel rat mAbs directed against the extracellular domains of Notch1 and Notch2, we find that Notch1 is already highly expressed on common lymphoid precursors in the bone marrow and remains at high levels during intrathymic maturation of CD4(-)CD8(-) thymocytes. Notch1 is progressively down-regulated at the CD4(+)CD8(+) and mature CD4(+) or CD8(+) thymic stages and is expressed at low levels on peripheral T cells. Immunofluorescence staining of thymus cryosections further revealed a localization of Notch1(+)CD25(-) cells adjacent to the thymus capsule. Notch1 was up-regulated on peripheral T cells following activation in vitro with anti-CD3 mAbs or infection in vivo with lymphocytic chorio-meningitis virus or Leishmania major. In contrast to Notch1, Notch2 was expressed at intermediate levels on common lymphoid precursors and CD117(+) early intrathymic subsets, but disappeared completely at subsequent stages of T cell development. However, transient up-regulation of Notch2 was also observed on peripheral T cells following anti-CD3 stimulation. Collectively our novel mAbs reveal a dynamic regulation of Notch1 and Notch2 surface expression during T cell development and activation. Furthermore they provide an important resource for future analysis of Notch receptors in various tissues including the hematopoietic system. PMID:19915064

  1. Activation of the Aryl Hydrocarbon Receptor by 10-Cl-BBQ Prevents Insulitis and Effector T Cell Development Independently of Foxp3+ Regulatory T Cells in Nonobese Diabetic Mice.

    PubMed

    Ehrlich, Allison K; Pennington, Jamie M; Wang, Xisheng; Rohlman, Diana; Punj, Sumit; Löhr, Christiane V; Newman, Matthew T; Kolluri, Siva K; Kerkvliet, Nancy I

    2016-01-01

    Aryl hydrocarbon receptor (AhR) activation by high-affinity ligands mediates immunosuppression in association with increased regulatory T cells (Tregs), making this transcription factor an attractive therapeutic target for autoimmune diseases. We recently discovered 10-chloro-7H-benzimidazo[2,1-a]benzo[de]iso-quinolin-7-one (10-Cl-BBQ), a nanomolar affinity AhR ligand with immunosuppressive activity and favorable pharmacologic properties. In this study, we tested the consequences of AhR activation in the NOD model. Oral 10-Cl-BBQ treatment prevented islet infiltration without clinical toxicity, whereas AhR-deficient NOD mice were not protected. Suppression of insulitis was associated with an increased frequency, but not total number, of Foxp3(+) Tregs in the pancreas and pancreatic lymph nodes. The requirement for Foxp3(+) cells in AhR-induced suppression of insulitis was tested using NOD.Foxp3(DTR) mice, which show extensive islet infiltration upon treatment with diphtheria toxin. AhR activation prevented the development of insulitis caused by the depletion of Foxp3(+) cells, demonstrating that Foxp3(+) cells are not required for AhR-mediated suppression and furthermore that the AhR pathway is able to compensate for the absence of Foxp3(+) Tregs, countering current dogma. Concurrently, the development of disease-associated CD4(+)Nrp1(+)Foxp3(-)ROR?t(+) cells was inhibited by AhR activation. Taken together, 10-Cl-BBQ is an effective, nontoxic AhR ligand for the intervention of immune-mediated diseases that functions independently of Foxp3(+) Tregs to suppress pathogenic T cell development. PMID:26573835

  2. Osteoprotegerin-Mediated Homeostasis of Rank+ Thymic Epithelial Cells Does Not Limit Foxp3+ Regulatory T Cell Development.

    PubMed

    McCarthy, Nicholas I; Cowan, Jennifer E; Nakamura, Kyoko; Bacon, Andrea; Baik, Song; White, Andrea J; Parnell, Sonia M; Jenkinson, Eric J; Jenkinson, William E; Anderson, Graham

    2015-09-15

    In the thymus, medullary thymic epithelial cells (mTEC) regulate T cell tolerance via negative selection and Foxp3(+) regulatory T cell (Treg) development, and alterations in the mTEC compartment can lead to tolerance breakdown and autoimmunity. Both the receptor activator for NF-?B (RANK)/RANK ligand (RANKL)/osteoprotegerin (OPG) axis and expression of the transcriptional regulator Aire are involved in the regulation of thymus medullary microenvironments. However, their impact on the mechanisms controlling mTEC homeostasis is poorly understood, as are the processes that enable the thymus medulla to support the balanced production of mTEC-dependent Foxp3(+) Treg. In this study, we have investigated the control of mTEC homeostasis and examined how this process impacts the efficacy of Foxp3(+) Treg development. Using newly generated RANK Venus reporter mice, we identify distinct RANK(+) subsets that reside within both the mTEC(hi) and mTEC(lo) compartments and that represent direct targets of OPG-mediated control. Moreover, by mapping OPG expression to a subset of Aire(+) mTEC, our data show how cis- and trans-acting mechanisms are able to control the thymus medulla by operating on multiple mTEC targets. Finally, we show that whereas the increase in mTEC availability in OPG-deficient (Tnfrsf11b(-/-)) mice impacts the intrathymic Foxp3(+) Treg pool by enhancing peripheral Treg recirculation back to the thymus, it does not alter the number of de novo Rag2pGFP(+)Foxp3(+) Treg that are generated. Collectively, our study defines patterns of RANK expression within the thymus medulla, and it shows that mTEC homeostasis is not a rate-limiting step in intrathymic Foxp3(+) Treg production. PMID:26254339

  3. Vitamin D3 metabolite calcidiol primes human dendritic cells to promote the development of immunomodulatory IL-10-producing T cells.

    PubMed

    Bakdash, Ghaith; van Capel, Toni M M; Mason, Lauren M K; Kapsenberg, Martien L; de Jong, Esther C

    2014-10-29

    Vitamin D is recognized as a potent immunosuppressive drug. The suppressive effects of vitamin D are attributed to its physiologically active metabolite 1,25 dihydroxy vitamin D3 (calcitriol), which was shown, to prime dendritic cells (DCs) to promote the development of regulatory T (Treg) cells. Despite the potential benefit in treating autoimmune diseases, clinical application of calcitriol is hindered by deleterious side effects manifested by hypercalcemia and hypercalciuria. Conversely, the physiological precursors of calcitriol, vitamin D3 (cholecalciferol) and its first metabolite 25-hydroxy vitamin D3 (calcidiol) are widely applied in the clinic due to their low calcimic burden. However, the mechanisms by which cholecalciferol and calcidiol may modulate adaptive immunity remain elusive. This prompted us to unravel the immunosuppressive capacity of these precursors by assessing their influence on DC functions and the subsequent polarization of naïve CD4(+) T cells. In this study we show that, whereas cholecalciferol has insignificant effects on DC maturation and cytokine production, it only weakly primed DCs to induce suppressive T cells. However, like calcitriol, calcidiol not only exerted an inhibitory effect on DC maturation and cytokine production, and primed DCs to promote the development of suppressive IL-10-producing Treg cells. Strikingly, in contrast to the population of IL-10-producing Treg cells induced by calcitriol-primed DCs, the IL-10-producing Treg cells induced by calcidiol-primed DCs exhibited sustained IFN-? production in face of their suppressive capacity. Experiments with the steroid synthesis inhibitor ketoconazole indicated that the immunomodulatory features of the precursors are dependent on their conversion into calcitriol. Collectively, calcidiol is a potent immune modulator, which may be more adequate than calcitriol for the treatment of chronic inflammatory diseases, since it is less hypercalcimic. This may be of particular interest for the treatment of allergic disease, where concurrent suppression and sustained IFN-? production by Treg cells effectively counterbalance the Th2-dominated immune responses. PMID:25236584

  4. Fbw7 Targets GATA3 through Cyclin-Dependent Kinase 2-Dependent Proteolysis and Contributes to Regulation of T-Cell Development

    PubMed Central

    Kitagawa, Kyoko; Shibata, Kiyoshi; Matsumoto, Akinobu; Matsumoto, Masaki; Ohhata, Tatsuya; Nakayama, Keiichi I.; Niida, Hiroyuki

    2014-01-01

    Proper development of T cells depends on lineage-specific regulators controlled transcriptionally and posttranslationally to ensure precise levels at appropriate times. Conditional inactivation of F-box protein Fbw7 in mouse T-cell development resulted in reduced thymic CD4 single-positive (SP) and splenic CD4+ and CD8+ cell proportions. Fbw7 deficiency skewed CD8 SP lineage differentiation, which exhibited a higher incidence of apoptosis. Similar perturbations during development of CD8-positive cells were reported with transgenic mice, which enforced GATA3 (T-cell differentiation regulator) expression throughout T-cell development. We observed augmented GATA3 in CD4/CD8 double negative (DN) stage 4, CD4 SP, and CD8 SP lineages in Fbw7-deficient thymocytes. Using overexpressed proteins in cultured cells, we demonstrated that Fbw7 bound to, ubiquitylated, and destabilized GATA3. Two Cdc4 phosphodegron (CPD) candidate sequences, consensus Fbw7 recognition domains, were identified in GATA3, and phosphorylation of Thr-156 in CPD was required for Fbw7-mediated ubiquitylation and degradation. Phosphorylation of GATA3 Thr-156 was detected in mouse thymocytes, and cyclin-dependent kinase 2 (CDK2) was identified as a respondent for phosphorylation at Thr-156. These observations suggest that Fbw7-mediated GATA3 regulation with CDK2-mediated phosphorylation of CPD contributes to the precise differentiation of T-cell lineages. PMID:24820417

  5. Development of an In Vitro Assay and Demonstration of Plasmodium berghei Liver-Stage Inhibition by TRAP-Specific CD8+ T Cells

    PubMed Central

    Longley, Rhea J.; Bauza, Karolis; Ewer, Katie J.; Hill, Adrian V. S.; Spencer, Alexandra J.

    2015-01-01

    The development of an efficacious vaccine against the Plasmodium parasite remains a top priority. Previous research has demonstrated the ability of a prime-boost virally vectored sub-unit vaccination regimen, delivering the liver-stage expressed malaria antigen TRAP, to produce high levels of antigen-specific T cells. The liver-stage of malaria is the main target of T cell-mediated immunity, yet a major challenge in assessing new T cell inducing vaccines has been the lack of a suitable pre-clinical assay. We have developed a flow-cytometry based in vitro T cell killing assay using a mouse hepatoma cell line, Hepa1-6, and Plasmodium berghei GFP expressing sporozoites. Using this assay, P. berghei TRAP-specific CD8+ T cell enriched splenocytes were shown to inhibit liver-stage parasites in an effector-to-target ratio dependent manner. Further development of this assay using human hepatocytes and P. falciparum would provide a new method to pre-clinically screen vaccine candidates and to elucidate mechanisms of protection in vitro. PMID:25822951

  6. Cutaneous T Cell Lymphoma

    MedlinePLUS

    ... slow-growing) in early stages, and a more aggressive form called “Sézary syndrome” (SS). Other less common CTCL ... like T-cell lymphoma l Cutaneous CD8+ expressing aggressive epidermotropic T-cell lymphoma l Gamma-delta T- ...

  7. T-cell count

    MedlinePLUS

    A T-cell count measures the number of T cells in the blood. Your doctor may order this test if you ... T cells are a type of lymphocyte. Lymphocytes are white blood cells. They make up part of the immune ...

  8. Granzyme B expression by CD8+ T cells is required for the development of experimental cerebral malaria.

    PubMed

    Haque, Ashraful; Best, Shannon E; Unosson, Klara; Amante, Fiona H; de Labastida, Fabian; Anstey, Nicholas M; Karupiah, Gunasegaran; Smyth, Mark J; Heath, William R; Engwerda, Christian R

    2011-06-01

    Parasite burden predicts disease severity in malaria and risk of death in cerebral malaria patients. In murine experimental cerebral malaria (ECM), parasite burden and CD8(+) T cells promote disease by mechanisms that are not fully understood. We found that the majority of brain-recruited CD8(+) T cells expressed granzyme B (GzmB). Furthermore, gzmB(-/-) mice harbored reduced parasite numbers in the brain as a consequence of enhanced antiparasitic CD4(+) T cell responses and were protected from ECM. We showed in these ECM-resistant mice that adoptively transferred, Ag-specific CD8(+) T cells migrated to the brain, but did not induce ECM until a critical Ag threshold was reached. ECM induction was exquisitely dependent on Ag-specific CD8(+) T cell-derived perforin and GzmB, but not IFN-?. In wild-type mice, full activation of brain-recruited CD8(+) T cells also depended on a critical number of parasites in this tissue, which in turn, was sustained by these tissue-recruited cells. Thus, an interdependent relationship between parasite burden and CD8(+) T cells dictates the onset of perforin/GzmB-mediated ECM. PMID:21525386

  9. Transcription factor and miRNA co-regulatory network reveals shared and specific regulators in the development of B cell and T cell

    PubMed Central

    Lin, Ying; Zhang, Qiong; Zhang, Hong-Mei; Liu, Wei; Liu, Chun-Jie; Li, Qiubai; Guo, An-Yuan

    2015-01-01

    The maturation process of lymphocyte was related to many blood diseases, such as lymphoma and lymphoid leukemia. Many TFs and miRNAs were separately studied in the development of B and T cells. In this study, we aim to discover the TF and miRNA co-regulation and identify key regulators in the B and T cells maturation. We obtained the candidate genes, miRNAs and TFs for each stage of their maturation, then constructed the TF-miRNA-gene feed-forward loops (FFLs) for each stage by our previous methods. Statistical test for FFLs indicated their enrichment and significance. TF-miRNA co-regulatory networks for each stage were constructed by combining their FFLs. Hub analysis revealed the key regulators in each stage, for example, MYC, STAT5A, PAX5 and miR-17?~?92 in the transition of pro-B cells into pre-B cells. We also identified a few common regulators and modules in two stages of B cell maturation (e.g. miR-146a/NFKB1/BCL11A) and two stages of T cell maturation (e.g. miR-20/CCND2/SORL1), as well as some shared regulators in the early stages of both B and T cell development. Our network will help to increase understanding of mature process of B and T cell, as well as the related blood diseases. PMID:26487345

  10. B cells help alloreactive T cells differentiate into memory T cells1

    PubMed Central

    Ng, Yue-Harn; Oberbarnscheidt, Martin H.; Chandramoorthy, Harish Chinna Konda; Hoffman, Rosemary; Chalasani, Geetha

    2010-01-01

    B cells are recognized as effector cells in allograft rejection that are dependent upon T cell help to produce alloantibodies causing graft injury. It is not known if B cells can also help T cells differentiate into memory cells in the alloimmune response. We found that in B cell-deficient hosts, differentiation of alloreactive T cells into effectors was intact whereas their development into memory T cells was impaired. To test if B cell help for T cells was required for their continued differentiation into memory T cells, activated T cells were sorted from alloimmunized mice and transferred either with or without B cells into naïve adoptive hosts. Activated T cells co-transferred with B cells gave rise to more memory T cells than those transferred without B cells and upon recall, mediated accelerated rejection of skin allografts. Co-transfer of B cells led to increased memory T cells by enhancing activated CD4 T cell proliferation and activated CD8 T cell survival. These results indicate that B cells help alloreactive T cell differentiation, proliferation and survival to generate optimal numbers of functional memory T cells. PMID:20883532

  11. T Cell-Dependence of Lassa Fever Pathogenesis

    PubMed Central

    Bergthaler, Andreas; Regen, Tommy; Schedensack, Mariann; Bestmann, Lukas; Verschoor, Admar; Kreutzfeldt, Mario; Brück, Wolfgang; Hanisch, Uwe-Karsten; Günther, Stephan; Pinschewer, Daniel D.

    2010-01-01

    Lassa virus (LASV), the causative agent of Lassa fever (LF), is endemic in West Africa, accounting for substantial morbidity and mortality. In spite of ongoing research efforts, LF pathogenesis and mechanisms of LASV immune control remain poorly understood. While normal laboratory mice are resistant to LASV, we report that mice expressing humanized instead of murine MHC class I (MHC-I) failed to control LASV infection and develop severe LF. Infection of MHC-I knockout mice confirmed a key role for MHC-I-restricted T cell responses in controlling LASV. Intriguingly we found that T cell depletion in LASV-infected HHD mice prevented disease, irrespective of high-level viremia. Widespread activation of monocyte/macrophage lineage cells, manifest through inducible NO synthase expression, and elevated IL-12p40 serum levels indicated a systemic inflammatory condition. The absence of extensive monocyte/macrophage activation in T cell-depleted mice suggested that T cell responses contribute to deleterious innate inflammatory reactions and LF pathogenesis. Our observations in mice indicate a dual role for T cells, not only protecting from LASV, but also enhancing LF pathogenesis. The possibility of T cell-driven enhancement and immunopathogenesis should be given consideration in future LF vaccine development. PMID:20360949

  12. T cell-dependence of Lassa fever pathogenesis.

    PubMed

    Flatz, Lukas; Rieger, Toni; Merkler, Doron; Bergthaler, Andreas; Regen, Tommy; Schedensack, Mariann; Bestmann, Lukas; Verschoor, Admar; Kreutzfeldt, Mario; Brück, Wolfgang; Hanisch, Uwe-Karsten; Günther, Stephan; Pinschewer, Daniel D

    2010-03-01

    Lassa virus (LASV), the causative agent of Lassa fever (LF), is endemic in West Africa, accounting for substantial morbidity and mortality. In spite of ongoing research efforts, LF pathogenesis and mechanisms of LASV immune control remain poorly understood. While normal laboratory mice are resistant to LASV, we report that mice expressing humanized instead of murine MHC class I (MHC-I) failed to control LASV infection and develop severe LF. Infection of MHC-I knockout mice confirmed a key role for MHC-I-restricted T cell responses in controlling LASV. Intriguingly we found that T cell depletion in LASV-infected HHD mice prevented disease, irrespective of high-level viremia. Widespread activation of monocyte/macrophage lineage cells, manifest through inducible NO synthase expression, and elevated IL-12p40 serum levels indicated a systemic inflammatory condition. The absence of extensive monocyte/macrophage activation in T cell-depleted mice suggested that T cell responses contribute to deleterious innate inflammatory reactions and LF pathogenesis. Our observations in mice indicate a dual role for T cells, not only protecting from LASV, but also enhancing LF pathogenesis. The possibility of T cell-driven enhancement and immunopathogenesis should be given consideration in future LF vaccine development. PMID:20360949

  13. Differential regulation of T helper phenotype development by interleukins 4 and 10 in an alpha beta T-cell-receptor transgenic system.

    PubMed Central

    Hsieh, C S; Heimberger, A B; Gold, J S; O'Garra, A; Murphy, K M

    1992-01-01

    To address the mechanisms controlling T helper (Th) phenotype development, we used DO10, a transgenic mouse line that expresses the alpha beta T-cell receptor from an ovalbumin-reactive T hybridoma, as a source of naive T cells that can be stimulated in vitro with ovalbumin peptide presented by defined antigen-presenting cells (APCs). We have examined the role of cytokines and APCs in the regulation of Th phenotype development. Interleukin 4 (IL-4) directs development toward the Th2 phenotype, stimulating IL-4 and silencing IL-2 and interferon gamma production in developing T cells. Splenic APCs direct development toward the Th1 phenotype when endogenous IL-10 is neutralized with anti-IL-10 antibody. The splenic APCs mediating these effects are probably macrophages or dendritic cells and not B cells, since IL-10 is incapable of affecting Th phenotype development when the B-cell hybridoma TA3 is used as the APC. These results suggest that early regulation of IL-4 and IL-10 in a developing immune response and the identity of the initiating APCs are critical in determining the Th phenotype of the developing T cells. PMID:1385868

  14. Role of protein Tyrosine Phosphatase PTPN22 in T cell signalling and autoimmunity 

    E-print Network

    Sood, Shatakshi

    2015-06-29

    Signals via the T cell receptor (TCR) are critical for the development of T cells in the thymus, maintenance of a self-tolerant peripheral T cell repertoire and the activation of T cells in secondary lymphoid organs. A ...

  15. Applying an adaptive watershed to the tissue cell quantification during T-cell migration and embryonic development.

    PubMed

    Zhu, D; Jarmin, S; Ribeiro, A; Prin, F; Xie, S Q; Sullivan, K; Briscoe, J; Gould, A P; Marelli-Berg, Federica M; Gu, Y

    2010-01-01

    Cell and particle quantification is one of the frequently used techniques in biology and clinical study. Variations of cell/particle population and/or protein expression level can provide information on many biological processes. In this chapter, we propose an image-based automatic quantification approach that can be applied to images from both fluorescence and electron microscopy. The algorithm uses local maxima to identify labelling targets and uses watershed segmentation to define their boundaries. The method is able to provide information on size, intensity centroids and average intensity within the labelling partitions. Further developed from this method, we demonstrated its applications in four different research projects, including recruitment enumeration of circulating T cell in non-lymphoid tissues, cell clustering in the early development of the chick embryo, gold particle localization and clustering in electron microscopy, and registration/co-localization of transcription factors in neural tube development of early chick embryo. The advantages and limitations of the method are also discussed. PMID:20379878

  16. Poor Predictive Value of Cytomegalovirus (CMV)–Specific T Cell Assays for the Development of CMV Retinitis in Patients with AIDS

    PubMed Central

    Jacobson, Mark A.; Tan, Qi Xuan; Girling, Valerie; Poon, C.; Van Natta, Mark; Jabs, Douglas A.; Inokuma, Margaret; Maecker, Holden T.; Bredt, Barry; Sinclair, Elizabeth

    2009-01-01

    Background We examined the potential clinical utility of using a cytomegalovirus (CMV)–specific T cell immunoassay to determine the risk of developing new-onset CMV retinitis (CMVR) in patients with acquired immunodeficiency syndrome (AIDS). Methods CMV-specific T cell assays were performed by multiparameter flow cytometry using stored peripheral blood mononuclear cells that had been obtained in an observational study 2–6 months before new-onset CMVR was diagnosed in case patients (at a study visit during which a dilated ophthalmologic examination revealed no evidence of CMVR) and at the same study visit in control subjects (matched by absolute CD4+ T cell count at entry) who did not subsequently develop retinitis during 1–6 years of study follow-up. Results There were no significant differences in CMV-specific CD4+ or CD8+ T cell interferon-? or interleukin-2 expression in peripheral blood mononuclear cells from case patients and control subjects. Although there were trends toward lower percentages and absolute numbers of CMV-specific, cytokine-expressing CD8+ T cells with a “late memory” phenotype (CD27?CD28?) as well as with an “early memory” phenotype (CD27+CD28+CD45RA+) in case patients than in control subjects, these differences were not statistically significant. Conclusions Many studies have reported that CMV-specific CD4+ and CD8+ T cell responses distinguish patients with active CMVR (i.e., who lack CMV-protective immunity) from those with inactive CMVR after immune restoration by antiretroviral treatment (i.e., who have CMV-protective immunity). However, the multiple CMV-specific immune responses we measured do not appear to have clinical utility for predicting the risk for patients with AIDS of developing new-onset CMVR with sufficient accuracy to be used in guiding therapeutic management. PMID:18173357

  17. Thymic B cells promote thymus-derived regulatory T cell development and proliferation.

    PubMed

    Lu, Fang-Ting; Yang, Wei; Wang, Yin-Hu; Ma, Hong-Di; Tang, Wei; Yang, Jing-Bo; Li, Liang; Ansari, Aftab A; Lian, Zhe-Xiong

    2015-07-01

    Thymic CD4(+) FoxP3(+) regulatory T (Treg) cells are critical for the development of immunological tolerance and immune homeostasis and requires contributions of both thymic dendritic and epithelial cells. Although B cells have been reported to be present within the thymus, there has not hitherto been a definition of their role in immune cell development and, in particular, whether or how they contribute to the Treg cellular thymic compartment. Herein, using both phenotypic and functional approaches, we demonstrate that thymic B cells contribute to the maintenance of thymic Treg cells and, using an in vitro culture system, demonstrate that thymic B cells contribute to the size of the thymic Treg compartment via cell-cell MHC II contact and the involvement of two independent co-stimulatory pathways that include interactions between the CD40/CD80/CD86 co-stimulatory molecules. Our data also suggest that thymic B cells promote the generation of thymic Treg cell precursors (pre-Treg cells), but not the conversion of FoxP3(+) Treg cells from pre-Treg cells. In addition, thymic B cells directly promote the proliferation of thymic Treg cells that is MHC II contact dependent with a minimal if any role for co-stimulatory molecules including CD40/CD80/CD86. Both pathways are independent of TGF?. In conclusion, we rigorously define the critical role of thymic B cells in the development of thymic Treg cells from non-Treg to precursor stage and in the proliferation of mature thymic Treg cells. PMID:26071985

  18. Development of CD4 T Cell Dependent Immunity Against N. brasiliensis Infection.

    PubMed

    Harvie, Marina; Camberis, Mali; Le Gros, Graham

    2013-01-01

    Of all the microbial infections relevant to mammals the relationship between parasitic worms and what constitutes and regulates a host protective immune response is perhaps the most complex and evolved. Nippostrongylus brasiliensis is a tissue migrating parasitic roundworm of rodents that exemplifies many of the salient features of parasitic worm infection, including parasite development through sequential larval stages as it migrates through specific tissue sites. Immune competent hosts respond to infection by N. brasiliensis with a rapid and selective development of a profound Th2 immune response that appears able to confer life long protective immunity against reinfection. This review details how the lung can be the site of migrating nematode immune killing and the gut a site of rapid immune mediated clearance of worms. Furthermore it appears that N. brasiliensis induced responses in the lung are sufficient for conferring immunity in lung and gut while infection of the gut only confers immunity in the gut. This review also covers the role of IL-4, STAT6, and the innate cytokines IL-25, IL-33, and thymic stromal lymphopoietin in the generation of CD4-mediated immunity against N. brasiliensis reinfection and discusses what cytokines might be involved in mediated killing or expulsion of helminth parasites. PMID:23518620

  19. IFN-?/? receptor signaling promotes regulatory T cell development and function under stress conditions.

    PubMed

    Metidji, Amina; Rieder, Sadiye Amcaoglu; Glass, Deborah Dacek; Cremer, Isabelle; Punkosdy, George A; Shevach, Ethan M

    2015-05-01

    Type I IFNs are a family of cytokines with antiviral and immunomodulatory properties. Although the antiviral effects of IFNs are well characterized, their immunomodulatory properties are less clear. To specifically address the effects of type I IFNs on T regulatory cells (Tregs), we studied mixed bone marrow chimeras between wild-type and IFN-?/? receptor (IFNAR) knockout (KO) mice, and heterozygous female mice expressing a Treg-specific deletion of the IFNAR. In these two models, IFNAR signaling promotes the development of the Treg lineage in the thymus and their survival in the periphery. IFNAR KO Tregs had a higher expression of the proapoptotic gene Bim and higher frequency of active caspase-positive cells. IFNAR KO Tregs from chimeric mice displayed a more naive phenotype, accompanied by lower levels of CD25 and phosphorylated STAT5. Therefore, in Tregs, IFNAR signaling may directly or indirectly affect phosphorylation of STAT5. In mixed chimeras with Scurfy fetal liver, Tregs derived from IFNAR KO bone marrow were unable to control T effector cell activation and tissue inflammation. Under stress conditions or in a competitive environment, IFNAR signaling may be required to maintain Treg homeostasis and function. PMID:25795758

  20. Induced and Natural Regulatory T Cells in the Development of Inflammatory Bowel Disease

    PubMed Central

    Mayne, Christopher G.; Williams, Calvin B.

    2013-01-01

    The mucosal immune system mediates contact between the host, and the trillions of microbes that symbiotically colonize the gastrointestinal tract. Failure to tolerate the antigens within this “extended self” can result in inflammatory bowel disease (IBD). Within the adaptive immune system, the most significant cells modulating this interaction are Foxp3+ regulatory T (Treg) cells. Treg cells can be divided into two primary subsets: “natural” Treg (nTreg) cells, and “adaptive” or “induced” Treg (iTreg). Recent research suggests that these subsets serve to play both independent and synergistic roles in mucosal tolerance. Studies from both mouse models and human patients suggest defects in Treg cells can play distinct causative roles in IBD. Numerous genetic, microbial, nutritional, and environmental factors that associate with IBD may also affect Treg cells. In this review we summarize the development and function of Treg cells, and how their regulatory mechanisms may fail, leading to a loss of mucosal tolerance. We discuss both animal models and studies of IBD patients suggesting Treg cell involvement in IBD, and consider how Treg cells may be used in future therapies. PMID:23656897

  1. Role of ?? T Cells in Lung Inflammation

    PubMed Central

    Born, Willi K.; Roark, Christina L.; Jin, Niyun; Wands, JM; Kemal Aydintug, M.; Huang, Yafei; Chain, Jennifer L.; Hahn, Youn-Soo; Simonian, Philip L.; Fontenot, Andrew P.; O'Brien, Rebecca L.

    2015-01-01

    The resident population of ?? T cells in the normal lung is small but during lung inflammation, ?? T cells can increase dramatically. Histological analysis reveals diverse interactions between ?? T cells and other pulmonary leukocytes. Studies in animal models show that ?? T cells play a role in allergic lung inflammation where they can protect normal lung function, that they also are capable of resolving infection-induced pulmonary inflammation, and that they can help preventing pulmonary fibrosis. Lung inflammation threatens vital lung functions. Protection of the lung tissues and their functions during inflammation is the net-effect of opposing influences of specialized subsets of ?? T cells as well as interactions of these cells with other pulmonary leukocytes. PMID:26550059

  2. The challenges and opportunities for the development of a T-cell epitope-based herpes simplex vaccine.

    PubMed

    Kuo, Tiffany; Wang, Christine; Badakhshan, Tina; Chilukuri, Sravya; BenMohamed, Lbachir

    2014-11-28

    Herpes simplex virus type 1 and type 2 (HSV-1 & HSV-2) infections have been prevalent since the ancient Greek times. To this day, they still affect a staggering number of over a billion individuals worldwide. HSV-1 infections are predominant than HSV-2 infections and cause potentially blinding ocular herpes, oro-facial herpes and encephalitis. HSV-2 infections cause painful genital herpes, encephalitis, and death in newborns. While prophylactic and therapeutic HSV vaccines remain urgently needed for centuries, their development has been difficult. During the most recent National Institute of Health (NIH) workshop titled "Next Generation Herpes Simplex Virus Vaccines: The Challenges and Opportunities", basic researchers, funding agencies, and pharmaceutical representatives gathered: (i) to assess the status of herpes vaccine research; and (ii) to identify the gaps and propose alternative approaches in developing a safe and efficient herpes vaccine. One "common denominator" among previously failed clinical herpes vaccine trials is that they either used a whole virus or a whole viral protein, which contain both "pathogenic symptomatic" and "protective asymptomatic" antigens and epitopes. In this report, we continue to advocate developing "asymptomatic" epitope-based sub-unit vaccine strategies that selectively incorporate "protective asymptomatic" epitopes which: (i) are exclusively recognized by effector memory CD4(+) and CD8(+) T cells (TEM cells) from "naturally" protected seropositive asymptomatic individuals; and (ii) protect human leukocyte antigen (HLA) transgenic animal models of ocular and genital herpes. We review the role of animal models in herpes vaccine development and discuss their current status, challenges, and prospects. PMID:25446827

  3. Harnessing endogenous miR-181a to segregate transgenic antigen receptor expression in developing versus post-thymic T cells in murine hematopoietic chimeras.

    PubMed

    Papapetrou, Eirini P; Kovalovsky, Damian; Beloeil, Laurent; Sant'angelo, Derek; Sadelain, Michel

    2009-01-01

    MicroRNAs (miRNAs) are small, noncoding RNAs that regulate gene expression by targeting complementary sequences, referred to as miRNA recognition elements (MREs), typically located in the 3' untranslated region of mRNAs. miR-181a is highly expressed in developing thymocytes and markedly downregulated in post-thymic T cells. We investigated whether endogenous miR-181a can be harnessed to segregate expression of chimeric antigen receptors (CARs) and TCRs between developing and mature T cells. Lentiviral-encoded antigen receptors were tagged with a miR-181a-specific MRE and transduced into mouse BM cells that were used to generate hematopoietic chimeras. Expression of a CAR specific for human CD19 (hCD19) was selectively suppressed in late double-negative and double-positive thymocytes, coinciding with the peak in endogenous miR-181a expression. Receptor expression was fully restored in post-thymic resting and activated T cells, affording protection against a subsequent challenge with hCD19+ tumors. Hematopoietic mouse chimeras engrafted with a conalbumin-specific TCR prone to thymic clonal deletion acquired peptide-specific T cell responsiveness only when the vector-encoded TCR transcript was similarly engineered to be subject to regulation by miR-181a. These results demonstrate the potential of miRNA-regulated transgene expression in stem cell-based therapies, including cancer immunotherapy. PMID:19033646

  4. Spontaneous development of IL-17-producing ?? T cells in the thymus occurs via a TGF?1-dependent mechanism1

    PubMed Central

    Do, Jeong-su; Fink, Pamela J.; Li, Lily; Spolski, Rosanne; Robinson, Janet; Leonard, Warren J.; Letterio, John J.; Min, Booki

    2010-01-01

    In naïve animals, ?? T cells are innate sources of IL-17, a potent proinflammatory cytokine mediating bacterial clearance as well as autoimmunity. However, mechanisms underlying the generation of these cells in vivo remain unclear. Here we show that TGF?1 plays a key role in the generation of IL-17+ ?? T cells, and that it mainly occurs in the thymus particularly during the postnatal period. Interestingly, IL-17+ ?? TCR+ thymocytes were mainly CD44highCD25low cells, which seem to derive from DN4 ?? TCR+ cells that acquired CD44 and IL-17 expression. Our findings identify a novel developmental pathway during which IL-17-competent ?? T cells arise in the thymus by a TGF?1-dependent mechanism. PMID:20061408

  5. Delta-like 4-mediated Notch signaling is required for early T-cell development in a three-dimensional thymic structure.

    PubMed

    Hirano, Ken-ichi; Negishi, Naoko; Yazawa, Masaki; Yagita, Hideo; Habu, Sonoko; Hozumi, Katsuto

    2015-08-01

    Delta-like 4 (Dll4)-mediated Notch signaling is critical for specifying T-cell fate, but how Dll4-mediated Notch signaling actually contributes to T-cell development in the thymus remains unclear. To explore this mechanism in the thymic three-dimensional structure, we performed fetal thymus organ culture using Dll4-deficient mice. DN1a/b+DN2mt cells, which had not yet committed to either the ?? T or ?? T/NK cell lineage, did not differentiate into the ?? T-cell lineage in Dll4-deficient thymus despite the lack of cell fate conversion into other lineages. However, DN3 cells efficiently differentiated into a later developmental stage of ?? T cells, the double-positive (DP) stage, although the proliferation was significantly impaired during the differentiation process. These findings suggest that the requirement for Notch signaling differs between the earliest and pre-TCR-bearing precursors and that continued Notch signaling is required for proper differentiation with active proliferation of ?? T lineage cells. Furthermore, we showed that Notch signaling increased the c-Myc expression in DN3 cells in the thymus and that its overexpression rescued the proliferation and differentiation of DN3 cells in the Dll4-null thymus. Therefore, c-Myc plays a central role in the transition from stage DN3 to DP as a downstream target of Notch signaling. PMID:25976373

  6. EmTIP, a T-Cell Immunomodulatory Protein Secreted by the Tapeworm Echinococcus multilocularis Is Important for Early Metacestode Development

    PubMed Central

    Nono, Justin Komguep; Lutz, Manfred B.; Brehm, Klaus

    2014-01-01

    Background Alveolar echinococcosis (AE), caused by the metacestode of the tapeworm Echinococcus multilocularis, is a lethal zoonosis associated with host immunomodulation. T helper cells are instrumental to control the disease in the host. Whereas Th1 cells can restrict parasite proliferation, Th2 immune responses are associated with parasite proliferation. Although the early phase of host colonization by E. multilocularis is dominated by a potentially parasitocidal Th1 immune response, the molecular basis of this response is unknown. Principal Findings We describe EmTIP, an E. multilocularis homologue of the human T-cell immunomodulatory protein, TIP. By immunohistochemistry we show EmTIP localization to the intercellular space within parasite larvae. Immunoprecipitation and Western blot experiments revealed the presence of EmTIP in the excretory/secretory (E/S) products of parasite primary cell cultures, representing the early developing metacestode, but not in those of mature metacestode vesicles. Using an in vitro T-cell stimulation assay, we found that primary cell E/S products promoted interferon (IFN)-? release by murine CD4+ T-cells, whereas metacestode E/S products did not. IFN-? release by T-cells exposed to parasite products was abrogated by an anti-EmTIP antibody. When recombinantly expressed, EmTIP promoted IFN-? release by CD4+ T-cells in vitro. After incubation with anti-EmTIP antibody, primary cells showed an impaired ability to proliferate and to form metacestode vesicles in vitro. Conclusions We provide for the first time a possible explanation for the early Th1 response observed during E. multilocularis infections. Our data indicate that parasite primary cells release a T-cell immunomodulatory protein, EmTIP, capable of promoting IFN-? release by CD4+ T-cells, which is probably driving or supporting the onset of the early Th1 response during AE. The impairment of primary cell proliferation and the inhibition of metacestode vesicle formation by anti-EmTIP antibodies suggest that this factor fulfills an important role in early E. multilocularis development within the intermediate host. PMID:24392176

  7. Epstein-Barr Virus Type 2 Latently Infects T Cells, Inducing an Atypical Activation Characterized by Expression of Lymphotactic Cytokines

    PubMed Central

    Coleman, Carrie B.; Wohlford, Eric M.; Smith, Nicholas A.; King, Christine A.; Ritchie, Julie A.; Baresel, Paul C.; Kimura, Hiroshi

    2014-01-01

    ABSTRACT Epstein-Barr virus (EBV) is a well-established B-cell-tropic virus associated with various lymphoproliferative diseases of both B-cell and non-B-cell origin. EBV is associated with a number of T-cell lymphomas; however, in vitro studies utilizing prototypical EBV type 1 (EBV-1) laboratory strains have generally failed to readily infect mature T cells in culture. The difficulties in performing in vitro T-cell experiments have left questions regarding the role of EBV in the pathogenesis of EBV-positive T-cell lymphoproliferative diseases largely unresolved. We report here that the EBV type 2 (EBV-2) strain displays a unique cell tropism for T cells. In remarkable contrast to EBV-1, EBV-2 readily infects primary T cells in vitro, demonstrating a propensity for CD8+ T cells. EBV-2 infection of purified T cells results in expression of latency genes and ultimately leads to T-cell activation, substantial proliferation, and profound alteration of cytokine expression. The pattern of cytokine production is strikingly skewed toward chemokines with roles in lymphocyte migration, demonstrating that EBV-2 has the ability to modulate normal T-cell processes. Collectively, these novel findings identify a previously unknown cell population potentially utilized by EBV-2 to establish latency and lay the foundation for further studies to elucidate the role of EBV in the pathogenesis of T-cell lymphoproliferative diseases. IMPORTANCE The ability of EBV to infect T cells is made apparent by its association with a variety of T-cell lymphoproliferative disorders. However, studies to elucidate the pathogenic role of EBV in these diseases have been limited by the inability to conduct in vitro T-cell infection experiments. Here, we report that EBV-2 isolates, compromised in the capacity to immortalize B cells, infect CD3+ T cells ex vivo and propose a working model of EBV-2 persistence where alteration of T-cell functions resulting from EBV-2 infection enhances the establishment of latency in B cells. If indeed EBV-2 utilizes T cells to establish a persistent infection, this could provide one mechanism for the association of EBV with T-cell lymphomas. The novel finding that EBV-2 infects T cells in culture will provide a model to understand the role EBV plays in the development of T-cell lymphomas. PMID:25505080

  8. Pushing the frontiers of T-cell vaccines: accurate measurement of human T-cell responses

    PubMed Central

    Saade, Fadi; Gorski, Stacey Ann; Petrovsky, Nikolai

    2013-01-01

    There is a need for novel approaches to tackle major vaccine challenges such as malaria, tuberculosis and HIV, among others. Success will require vaccines able to induce a cytotoxic T-cell response – a deficiency of most current vaccine approaches. The successful development of T-cell vaccines faces many hurdles, not least being the lack of consensus on a standardized T-cell assay format able to be used as a correlate of vaccine efficacy. Hence, there remains a need for reproducible measures of T-cell immunity proven in human clinical trials to correlate with vaccine protection. The T-cell equivalent of a neutralizing antibody assay would greatly accelerate the development and commercialization of T-cell vaccines. Recent advances have seen a plethora of new T-cell assays become available, including some like cytometry by time-of-flight with extreme multiparameter T-cell phenotyping capability. However, whether it is historic thymidine-based proliferation assays or sophisticated new cytometry assays, each assay has its relative advantages and disadvantages, and relatively few of these assays have yet to be validated in large-scale human vaccine trials. This review examines the current range of T-cell assays and assesses their suitability for use in human vaccine trials. Should one or more of these assays be accepted as an agreed surrogate of T-cell protection by a regulatory agency, this would significantly accelerate the development of T-cell vaccines. PMID:23252389

  9. IL-7 Is Essential for Homeostatic Control of T Cell Metabolism In Vivo

    PubMed Central

    Jacobs, Sarah R.; Michalek, Ryan D.; Rathmell, Jeffrey C.

    2010-01-01

    It has become apparent that T cells require growth signals to maintain function and viability necessary to maintain proper immune homeostasis. One means by which cell extrinsic signals may mediate these effects is by sustaining sufficient basal cell metabolism to prevent cell atrophy. The role of metabolism and the specific growth factors essential to maintain metabolism of mature T cells in vivo, however, are poorly defined. As IL-7 is a nonredundant cytokine required for T cell development and survival and can regulate T cell metabolism in vitro, we hypothesized it may be essential to sustain metabolism of resting T cells in vivo. Thus, we generated a model for conditional expression of IL-7R in mature T cells. After IL-7R deletion in a generally normal lymphoid environment, T cells had reduced responses to IL-7, including abrogated signaling and maintenance of antiapoptotic Bcl-2 family expression that corresponded to decreased survival in vitro. T cell survival in vivo was also reduced after loss of the IL-7R in a T cell-intrinsic manner. Additionally, IL-7R deletion resulted in delayed growth and proliferation following stimulation. Importantly, in vivo excision of IL-7R led to T cell atrophy that was characterized by delayed mitogenesis and reduced glycolytic flux. These data are the first to identify an in vivo requirement for a specific cell extrinsic signal to sustain lymphocyte metabolism and suggest that control of glycolysis by IL-7R may contribute to the well-described roles of IL-7 in T cell development, homeostatic proliferation, and survival. PMID:20194717

  10. Intracellular signaling from the T cell receptor (TCR) is important in the development of immature T cells in the thymus before they migrate to the peripheral tissues as mature T

    E-print Network

    Jackson, Robert B.

    a unique antigen (5, 6). However, amongst the large pool of immature thymocytes produced, only about 2 that are released into peripheral tissues, such as the spleen and lymph nodes (7, 8). The T cell population

  11. Homeostasis and effector function of lymphopenia-induced ‘memory-like’ T cells in constitutively T cell-depleted mice.1

    PubMed Central

    Voehringer, David; Liang, Hong-Erh; Locksley, Richard M.

    2009-01-01

    Summary Naive T lymphocytes acquire a phenotype similar to antigen-experienced memory T cells as a result of proliferation under lymphopenic conditions. Such ‘memory-like’ T cells (TML) constitute a large fraction of the peripheral T cell pool in patients recovering from T cell ablative therapies, HIV patients under highly active antiretroviral therapy and in the elderly population. To generate a model which allows characterization of TML cells without adoptive transfer, irradiation or thymectomy, we developed genetically modified mice which express diphtheria toxin A under control of a loxP flanked stop cassette (R-DTA mice). Crossing these mice to CD4Cre mice resulted in efficient ablation of CD4 single positive thymocytes whereas double positive and CD8 single positive thymocytes were only partially affected. In the periphery the pool of naïve (CD44lo CD62Lhi) T cells was depleted. However, some T cells were resistant to Cre-activity, escaped deletion in the thymus and underwent lymphopenia-induced proliferation resulting in a pool of TML cells that was similar in size and turnover to the pool of CD44hiCD62Llo memory-phenotype T cells in control mice. CD4Cre/R-DTA mice remained lymphopenic despite the large available immunological ‘space’ and normal antigen-induced T cell proliferation. CD4Cre/R-DTA mice showed a biased T cell receptor repertoire indicating oligoclonal T cell expansion. Infection with the helminth Nippostrongylus brasiliensis resulted in diminished effector cell recruitment and impaired worm expulsion demonstrating that TML cells are not sufficient to mediate an effective immune response. PMID:18354198

  12. T cell lipid peroxidation induces ferroptosis and prevents immunity to infection

    PubMed Central

    Matsushita, Mai; Freigang, Stefan; Schneider, Christoph; Conrad, Marcus; Bornkamm, Georg W.

    2015-01-01

    The selenoenzyme glutathione peroxidase 4 (Gpx4) is a major scavenger of phospholipid hydroperoxides. Although Gpx4 represents a key component of the reactive oxygen species-scavenging network, its relevance in the immune system is yet to be defined. Here, we investigated the importance of Gpx4 for physiological T cell responses by using T cell–specific Gpx4-deficient mice. Our results revealed that, despite normal thymic T cell development, CD8+ T cells from T?Gpx4/?Gpx4 mice had an intrinsic defect in maintaining homeostatic balance in the periphery. Moreover, both antigen-specific CD8+ and CD4+ T cells lacking Gpx4 failed to expand and to protect from acute lymphocytic choriomeningitis virus and Leishmania major parasite infections, which were rescued with diet supplementation of high dosage of vitamin E. Notably, depletion of the Gpx4 gene in the memory phase of viral infection did not affect T cell recall responses upon secondary infection. Ex vivo, Gpx4-deficient T cells rapidly accumulated membrane lipid peroxides and concomitantly underwent cell death driven by ferroptosis but not necroptosis. These studies unveil an essential role of Gpx4 for T cell immunity. PMID:25824823

  13. T cells promote the regeneration of neural precursor cells in the hippocampus of Alzheimer's disease mice

    PubMed Central

    Liu, Jing; Ma, Yuxin; Tian, Sumin; Zhang, Li; Zhao, Mengmeng; Zhang, Yaqiong; Xu, Dachuan

    2014-01-01

    Alzheimer's disease is closely associated with disorders of neurogenesis in the brain, and growing evidence supports the involvement of immunological mechanisms in the development of the disease. However, at present, the role of T cells in neuronal regeneration in the brain is unknown. We injected amyloid-beta 1–42 peptide into the hippocampus of six BALB/c wild-type mice and six BALB/c-nude mice with T-cell immunodeficiency to establish an animal model of Alzheimer's disease. A further six mice of each genotype were injected with same volume of normal saline. Immunohistochemistry revealed that the number of regenerated neural progenitor cells in the hippocampus of BALB/c wild-type mice was significantly higher than that in BALB/c-nude mice. Quantitative fluorescence PCR assay showed that the expression levels of peripheral T cell-associated cytokines (interleukin-2, interferon-?) and hippocampal microglia-related cytokines (interleukin-1?, tumor necrosis factor-?) correlated with the number of regenerated neural progenitor cells in the hippocampus. These results indicate that T cells promote hippocampal neurogenesis in Alzheimer's disease and T-cell immunodeficiency restricts neuronal regeneration in the hippocampus. The mechanism underlying the promotion of neuronal regeneration by T cells is mediated by an increased expression of peripheral T cells and central microglial cytokines in Alzheimer's disease mice. Our findings provide an experimental basis for understanding the role of T cells in Alzheimer's disease. PMID:25317172

  14. WASH Knockout T Cells Demonstrate Defective Receptor Trafficking, Proliferation, and Effector Function

    PubMed Central

    Piotrowski, Joshua T.; Gomez, Timothy S.; Schoon, Renee A.; Mangalam, Ashutosh K.

    2013-01-01

    WASH is an Arp2/3 activator of the Wiskott-Aldrich syndrome protein superfamily that functions during endosomal trafficking processes in collaboration with the retromer and sorting nexins, but its in vivo function has not been examined. To elucidate the physiological role of WASH in T cells, we generated a WASH conditional knockout (WASHout) mouse model. Using CD4Cre deletion, we found that thymocyte development and naive T cell activation are unaltered in the absence of WASH. Surprisingly, despite normal T cell receptor (TCR) signaling and interleukin-2 production, WASHout T cells demonstrate significantly reduced proliferative potential and fail to effectively induce experimental autoimmune encephalomyelitis. Interestingly, after activation, WASHout T cells fail to maintain surface levels of TCR, CD28, and LFA-1. Moreover, the levels of the glucose transporter, GLUT1, are also reduced compared to wild-type T cells. We further demonstrate that the loss of surface expression of these receptors in WASHout cells results from aberrant accumulation within the collapsed endosomal compartment, ultimately leading to degradation within the lysosome. Subsequently, activated WASHout T cells experience reduced glucose uptake and metabolic output. Thus, we found that WASH is a newly recognized regulator of TCR, CD28, LFA-1, and GLUT1 endosome-to-membrane recycling. Aberrant trafficking of these key T cell proteins may potentially lead to attenuated proliferation and effector function. PMID:23275443

  15. Developmental exposure to 2,3,7,8 tetrachlorodibenzo-p-dioxin attenuates later-life Notch1-mediated T cell development and leukemogenesis.

    PubMed

    Ahrenhoerster, Lori S; Leuthner, Tess C; Tate, Everett R; Lakatos, Peter A; Laiosa, Michael D

    2015-03-01

    Over half of T cell acute lymphoblastic leukemia (T-ALL) patients have activating mutations in the Notch gene. Moreover, the contaminant 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD) is a known carcinogen that mediates its toxicity through the aryl hydrocarbon receptor (AHR), and crosstalk between activated AHR and Notch signaling pathways has previously been observed. Given the importance of Notch signaling in thymocyte development and T-ALL disease progression, we hypothesized that the activated AHR potentiates disease initiation and progression in an in vivo model of Notch1-induced thymoma. This hypothesis was tested utilizing adult and developmental exposure paradigms to TCDD in mice expressing a constitutively active Notch1 transgene (Notch(ICN-TG)). Following exposure of adult Notch(ICN-TG) mice to a single high dose of TCDD, we observed a significant increase in the efficiency of CD8 thymocyte generation. We next exposed pregnant mice to 3?g/kg of TCDD throughout gestation and lactation to elucidate effects of developmental AHR activation on later-life T cell development and T-ALL-like thymoma susceptibility induced by Notch1. We found that the vehicle-exposed Notch(ICN-TG) offspring have a peripheral T cell pool heavily biased toward the CD4 lineage, while TCDD-exposed Notch(ICN-TG) offspring were biased toward the CD8 lineage. Furthermore, while the vehicle-exposed NotchICN-TG mice showed increased splenomegaly and B to T cell ratios indicative of disease, mice developmentally exposed to TCDD were largely protected from disease. These studies support a model where developmental AHR activation attenuates later-life Notch1-dependent impacts on thymocyte development and disease progression. PMID:25585350

  16. Impaired T-Cell Function in B-Cell Lymphoma: A Direct Consequence of Events at the Immunological Synapse?

    PubMed Central

    Nassef Kadry Naguib Roufaiel, Marian; Wells, James W.; Steptoe, Raymond J.

    2015-01-01

    Tumors can escape immune destruction through the development of antigen loss variants and loss of antigen processing/presentation pathways, thereby rendering them invisible to T cells. Alternatively, mechanisms of peripheral T-cell tolerance that would normally be important for protection from the development of autoimmunity may also be co-opted to (i) generate an immuno-inhibitory tumor environment, (ii) promote development of regulatory cell populations, or (iii) cell-intrinsically inactivate tumor-specific T cells. Emerging evidence suggests that T-cell function is impaired in hematological malignancies, which may manifest from cognate interactions between T cells and the tumor. The immunological synapse forms the cognate T-cell and antigen-presenting cell interaction and is the site where key signalling events, including those delivered by co-inhibitory receptors, that determine the fate of T cells occur. Here, we review evidence that events at the immune synapse between T cells and malignant B cells and alterations in immune synapse function may contribute to loss of T-cell function in B-cell malignancies. PMID:26082776

  17. Immunoregulatory T Cell Function in Multiple Myeloma

    PubMed Central

    Ozer, H.; Han, T.; Henderson, E. S.; Nussbaum, A.; Sheedy, D.

    1981-01-01

    Multiple myeloma is a malignancy characterized by uncontrolled monoclonal B cell differentiation and immunoglobulin production. In most instances, there is concomitant reduction in polyclonal differentiation and immunoglobulin synthesis both in vivo and in vitro. In in vitro pokeweed mitogen-induced B cell differentiation assays, proliferation and polyclonal immunoglobulin secretion optimally requires T cell help and can be inhibited both by monocytes and suppressor T cells. Helper function and monocyte-mediated suppression are relatively radio-resistant whereas T suppressor function is sensitive to 2,000 rad x-irradiation. We have examined myeloma T cell subset function in this assay using recombinations of isolated patient and normal B cells, T cells, and T cell subsets. Monocytes were removed by a carbonyl iron ingestion technique, normal and myeloma T cells were fractionated on the basis of Fc receptors for immunoglobulin (Ig) G (T?) or IgM (T? or T non-?), and proliferation and IgG secretion after co-culture determined by [3H]thymidine incorporation and radio-immunoassay, respectively. Myeloma B cells demonstrate quantitatively and qualitatively normal blastogenic responses and are appropriately regulated by either autologous or allogeneic T helper and suppressor subsets. Despite normal proliferation, however, myeloma B cells remain deficient in subsequent differentiation and immunoglobulin secretion even when co-cultured in the absence of monocytes or suppressor T cells and the presence of normal helper cells. Myeloma T cell populations, in contrast, are entirely normal in helper capacity over a range of T:B ratios but are markedly deficient in radiosensitive and concanavalin A-induced suppressor activity. T suppressor cell dysfunction in multiple myeloma is apparently due to a deficit in the T non-? suppressor subset, whereas T? cells, although proportionately reduced, are functionally normal. This unique T suppressor deficit reflects the heterogeneity of suppressor mechanisms in this disease and may represent a compensatory response to the monoclonal proliferation or the involvement of regulatory T cells in the pathogenesis of the malignancy. PMID:6451635

  18. CD4 T cells play important roles in maintaining IL-17-producing ?? T cell subsets in naïve animals

    PubMed Central

    Do, Jeong-Su; Visperas, Anabelle; O’Brien, Rebecca L.; Min, Booki

    2011-01-01

    A proportional balance between ?? and ?? T cell subsets in the periphery is exceedingly well maintained via a homeostatic mechanism. However, a cellular mechanism underlying the regulation remains undefined. We recently reported that a subset of developing ?? T cells spontaneously acquire IL-17-producing capacity even within naïve animals via a TGF?1-dependent mechanism, thus considered ‘einnate’ IL-17-producing cells. Here we report that ?? T cells generated within ?? T cell (or CD4 T cell)-deficient environments displayed altered cytokine profiles; particularly, ‘einnate’ IL-17 expression was significantly impaired compared to those in wild type mice. Impaired IL-17 production in ?? T cells was directly related to the CD4 T cell deficiency, because depletion of CD4 T cells in wild type mice diminished and adoptive CD4 T cell transfer into TCR??/? mice restored IL-17 expression in ?? T cells. CD4 T cell-mediated IL-17 expression required TGF?1. Moreover, Th17 but not Th1 or Th2 effector CD4 T cells were highly efficient in enhancing ?? T cell IL-17 expression. Taken together, our results highlight a novel CD4 T cell-dependent mechanism that shapes the generation of IL-17+ ?? T cells in naïve settings. PMID:21647171

  19. Prenatal exposure to radiofrequencies: effects of WiFi signals on thymocyte development and peripheral T cell compartment in an animal model.

    PubMed

    Laudisi, Federica; Sambucci, Manolo; Nasta, Francesca; Pinto, Rosanna; Lodato, Rossella; Altavista, Pierluigi; Lovisolo, Giorgio Alfonso; Marino, Carmela; Pioli, Claudio

    2012-12-01

    Wireless local area networks are an increasing alternative to wired data networks in workplaces, homes, and public areas. Concerns about possible health effects of this type of signal, especially when exposure occurs early in life, have been raised. We examined the effects of prenatal (in utero) exposure to wireless fidelity (WiFi) signal-associated electromagnetic fields (2450?MHz center-frequency band) on T cell development and function. Pregnant mice were exposed whole body to a specific absorption rate of 4?W/kg, 2?h per day, starting 5 days after mating and ending 1 day before the expected delivery. Sham-exposed and cage control groups were used as controls. No effects on cell count, phenotype, and proliferation of thymocytes were observed. Also, spleen cell count, CD4/CD8 cell frequencies, T cell proliferation, and cytokine production were not affected by the exposure. These findings were consistently observed in the male and female offspring at early (5 weeks of age) and late (26 weeks of age) time points. Nevertheless, the expected differences associated with aging and/or gender were confirmed. In conclusion, our results do not support the hypothesis that the exposure to WiFi signals during prenatal life results in detrimental effects on the immune T cell compartment. PMID:22556007

  20. Using T-Cells for Transplantation and Autoimmune Therapy

    Cancer.gov

    Transplant complications and autoimmune diseases are primarily caused by T-cell immune responses against normal host tissue or transplanted tissues. Current treatment for these disorders is often not effective, and is typically associated with significant side effects, including global immune suppression. Researchers at NCI's Experimental Transplantation and Immunology Branch have developed a cellular therapy to treat graft-vs.-host disease (GVHD) that results from hematopoetic transplant and other autoimmune disorders.

  1. Visualizing T Cell Migration in situ

    PubMed Central

    Benechet, Alexandre P.; Menon, Manisha; Khanna, Kamal M.

    2014-01-01

    Mounting a protective immune response is critically dependent on the orchestrated movement of cells within lymphoid tissues. The structure of secondary lymphoid organs regulates immune responses by promoting optimal cell–cell and cell–extracellular matrix interactions. Naïve T cells are initially activated by antigen presenting cells in secondary lymphoid organs. Following priming, effector T cells migrate to the site of infection to exert their functions. Majority of the effector cells die while a small population of antigen-specific T cells persists as memory cells in distinct anatomical locations. The persistence and location of memory cells in lymphoid and non-lymphoid tissues is critical to protect the host from re-infection. The localization of memory T cells is carefully regulated by several factors including the highly organized secondary lymphoid structure, the cellular expression of chemokine receptors and compartmentalized secretion of their cognate ligands. This balance between the anatomy and the ordered expression of cell surface and soluble proteins regulates the subtle choreography of T cell migration. In recent years, our understanding of cellular dynamics of T cells has been advanced by the development of new imaging techniques allowing in situ visualization of T cell responses. Here, we review the past and more recent studies that have utilized sophisticated imaging technologies to investigate the migration dynamics of naïve, effector, and memory T cells. PMID:25120547

  2. Memory T Cell Migration.

    PubMed

    Zhang, Qianqian; Lakkis, Fadi G

    2015-01-01

    Immunological memory is a key feature of adaptive immunity. It provides the organism with long-lived and robust protection against infection. In organ transplantation, memory T cells pose a significant threat by causing allograft rejection that is generally resistant to immunosuppressive therapy. Therefore, a more thorough understanding of memory T cell biology is needed to improve the survival of transplanted organs without compromising the host's ability to fight infections. This review will focus on the mechanisms by which memory T cells migrate to the site where their target antigen is present, with particular emphasis on their migration to transplanted organs. First, we will define the known subsets of memory T cells (central, effector, and tissue resident) and their circulation patterns. Second, we will review the cellular and molecular mechanisms by which memory T cells migrate to inflamed and non-inflamed tissues and highlight the emerging paradigm of antigen-driven, trans-endothelial migration. Third, we will discuss the relevance of this knowledge to organ transplantation and the prevention or treatment of allograft rejection. PMID:26483794

  3. Memory T Cell Migration

    PubMed Central

    Zhang, Qianqian; Lakkis, Fadi G.

    2015-01-01

    Immunological memory is a key feature of adaptive immunity. It provides the organism with long-lived and robust protection against infection. In organ transplantation, memory T cells pose a significant threat by causing allograft rejection that is generally resistant to immunosuppressive therapy. Therefore, a more thorough understanding of memory T cell biology is needed to improve the survival of transplanted organs without compromising the host’s ability to fight infections. This review will focus on the mechanisms by which memory T cells migrate to the site where their target antigen is present, with particular emphasis on their migration to transplanted organs. First, we will define the known subsets of memory T cells (central, effector, and tissue resident) and their circulation patterns. Second, we will review the cellular and molecular mechanisms by which memory T cells migrate to inflamed and non-inflamed tissues and highlight the emerging paradigm of antigen-driven, trans-endothelial migration. Third, we will discuss the relevance of this knowledge to organ transplantation and the prevention or treatment of allograft rejection. PMID:26483794

  4. Development of replication-defective lymphocytic choriomeningitis virus vectors for the induction of potent CD8+ T cell immunity.

    PubMed

    Flatz, Lukas; Hegazy, Ahmed N; Bergthaler, Andreas; Verschoor, Admar; Claus, Christina; Fernandez, Marylise; Gattinoni, Luca; Johnson, Susan; Kreppel, Florian; Kochanek, Stefan; Broek, Maries van den; Radbruch, Andreas; Lévy, Frédéric; Lambert, Paul-Henri; Siegrist, Claire-Anne; Restifo, Nicholas P; Löhning, Max; Ochsenbein, Adrian F; Nabel, Gary J; Pinschewer, Daniel D

    2010-03-01

    Lymphocytic choriomeningitis virus (LCMV) exhibits natural tropism for dendritic cells and represents the prototypic infection that elicits protective CD8(+) T cell (cytotoxic T lymphocyte (CTL)) immunity. Here we have harnessed the immunobiology of this arenavirus for vaccine delivery. By using producer cells constitutively synthesizing the viral glycoprotein (GP), it was possible to replace the gene encoding LCMV GP with vaccine antigens to create replication-defective vaccine vectors. These rLCMV vaccines elicited CTL responses that were equivalent to or greater than those elicited by recombinant adenovirus 5 or recombinant vaccinia virus in their magnitude and cytokine profiles, and they exhibited more effective protection in several models. In contrast to recombinant adenovirus 5, rLCMV failed to elicit vector-specific antibody immunity, which facilitated re-administration of the same vector for booster vaccination. In addition, rLCMV elicited T helper type 1 CD4+ T cell responses and protective neutralizing antibodies to vaccine antigens. These features, together with low seroprevalence in humans, suggest that rLCMV may show utility as a vaccine platform against infectious diseases and cancer. PMID:20139992

  5. Development of replication-defective lymphocytic choriomeningitis virus vectors for the induction of potent CD8+ T cell immunity

    PubMed Central

    Flatz, Lukas; Hegazy, Ahmed N; Bergthaler, Andreas; Verschoor, Admar; Claus, Christina; Fernandez, Marylise; Gattinoni, Luca; Johnson, Susan; Kreppel, Florian; Kochanek, Stefan; van den Broek, Maries; Radbruch, Andreas; Lévy, Frédéric; Lambert, Paul-Henri; Siegrist, Claire-Anne; Restifo, Nicholas P; Löhning, Max; Ochsenbein, Adrian F; Nabel, Gary J; Pinschewer, Daniel D

    2011-01-01

    Lymphocytic choriomeningitis virus (LCMV) exhibits natural tropism for dendritic cells and represents the prototypic infection that elicits protective CD8+ T cell (cytotoxic T lymphocyte (CTL)) immunity. Here we have harnessed the immunobiology of this arenavirus for vaccine delivery. By using producer cells constitutively synthesizing the viral glycoprotein (GP), it was possible to replace the gene encoding LCMV GP with vaccine antigens to create replication-defective vaccine vectors. These rLCMV vaccines elicited CTL responses that were equivalent to or greater than those elicited by recombinant adenovirus 5 or recombinant vaccinia virus in their magnitude and cytokine profiles, and they exhibited more effective protection in several models. In contrast to recombinant adenovirus 5, rLCMV failed to elicit vector-specific antibody immunity, which facilitated re-administration of the same vector for booster vaccination. In addition, rLCMV elicited T helper type 1 CD4+ T cell responses and protective neutralizing antibodies to vaccine antigens. These features, together with low seroprevalence in humans, suggest that rLCMV may show utility as a vaccine platform against infectious diseases and cancer. PMID:20139992

  6. Regulation of T-cell responses by PTEN

    PubMed Central

    Buckler, Jodi L.; Liu, Xiaohe; Turka, Laurence A.

    2010-01-01

    Summary The phosphoinositide 3-kinase (PI3K) signaling pathway plays a critical role in the development, activation, and homeostasis of T cells by modulating the expression of survival and mitogenic factors in response to a variety of stimuli. Ligation of the antigen receptor, costimulatory molecules, and cytokine receptors activate PI3K, resulting in the production of the lipid second messenger phosphatidylinositol-3,4,5-triphosphate (PIP3). A number of molecules help to regulate the activity of this pathway, including the lipid phosphatase PTEN (phosphatase and tensin homolog deleted on chromosome 10). By limiting the amount of PIP3 available within the cell, PTEN directly opposes PI3K activity and influences the selection of developing thymocytes as well as the activation requirements of mature T cells. T cells with unchecked PI3K activity, as a result of PTEN deficiency, contribute to the development of both autoimmune disease and lymphoma. This review dissects our current understanding of PI3K and PTEN and discusses why appropriate balance of these molecules is necessary to maintain normal T-cell responses. PMID:18759931

  7. Reduction of T Cell Receptor Diversity in NOD Mice Prevents Development of Type 1 Diabetes but Not Sjögren’s Syndrome

    PubMed Central

    Kern, Joanna; Drutel, Robert; Leanhart, Silvia; Bogacz, Marek; Pacholczyk, Rafal

    2014-01-01

    Non-obese diabetic (NOD) mice are well-established models of independently developing spontaneous autoimmune diseases, Sjögren’s syndrome (SS) and type 1 diabetes (T1D). The key determining factor for T1D is the strong association with particular MHCII molecule and recognition by diabetogenic T cell receptor (TCR) of an insulin peptide presented in the context of I-Ag7 molecule. For SS the association with MHCII polymorphism is weaker and TCR diversity involved in the onset of the autoimmune phase of SS remains poorly understood. To compare the impact of TCR diversity reduction on the development of both diseases we generated two lines of TCR transgenic NOD mice. One line expresses transgenic TCR? chain originated from a pathogenically irrelevant TCR, and the second line additionally expresses transgenic TCR?mini locus. Analysis of TCR sequences on NOD background reveals lower TCR diversity on Treg cells not only in the thymus, but also in the periphery. This reduction in diversity does not affect conventional CD4+ T cells, as compared to the TCRmini repertoire on B6 background. Interestingly, neither transgenic TCR? nor TCRmini mice develop diabetes, which we show is due to lack of insulin B:9–23 specific T cells in the periphery. Conversely SS develops in both lines, with full glandular infiltration, production of autoantibodies and hyposalivation. It shows that SS development is not as sensitive to limited availability of TCR specificities as T1D, which suggests wider range of possible TCR/peptide/MHC interactions driving autoimmunity in SS. PMID:25379761

  8. Immunopathology of experimental Chagas' disease: binding of T cells to Trypanosoma cruzi-infected heart tissue.

    PubMed Central

    Mortatti, R C; Maia, L C; de Oliveira, A V; Munk, M E

    1990-01-01

    The immunopathology of Chagas' disease was studied in the experimental model of chronic infection in C57BL/10JT or mice. Sublethal infection with Trypanosoma cruzi, Y strain, induced specific antibodies and a delayed hypersensitivity response to parasite antigens. Mice developed chronic chagasic myocarditis but not skeletal muscle myositis. Binding of T cells to infected heart tissue was investigated during short-term cocultivation of lymphocytes with heart cryostat sections. T cells from infected mice and from normal controls bound equally to myocardium and liver sections from both infected and normal mice. A search in depth was attempted with cells heavily tagged with 99mTc. Labeled T cells from chagasic mice bound to both normal and infected myocardium slices. 99mTc-labeled T cells from controls gave the same binding values. Glass-adherent spleen cells behaved identically to T cells. Prior treatment of the tissue with serum from chronically infected mice did not increase the number of binding cells. Peritoneal macrophages tagged with 99mTc-sulfur colloid also bound to infected myocardium slices. The binding of macrophages was not changed by pretreatment of infected tissue with anti-T, cruzi antibodies. In short, this work did not detect any population of T cells or macrophages which could bind specifically to infected heart tissue to initiate an autoreactive process. Images PMID:2228230

  9. The Type of Responder T-Cell Has a Significant Impact in a Human In Vitro Suppression Assay

    PubMed Central

    Jana, Srikanta; Campbell, Hope; Woodliff, Jeffrey; Waukau, Jill; Jailwala, Parthav; Ghorai, Jugal; Ghosh, Soumitra; Glisic, Sanja

    2010-01-01

    Background In type 1 diabetes (T1D), a prototypic autoimmune disease, effector T cells destroy beta cells. Normally, CD4+CD25+high, or natural regulatory T cells (Tregs), counter this assault. In autoimmunity, the failure to suppress CD4+CD25low T cells is important for disease development. However, both Treg dysfunction and hyperactive responder T-cell proliferation contribute to disease. Methods/Principal Findings We investigated human CD4+CD25low T cells and compared them to CD4+CD25- T cells in otherwise equivalent in vitro proliferative conditions. We then asked whether these differences in suppression are exacerbated in T1D. In both single and co-culture with Tregs, the CD4+CD25low T cells divided more rapidly than CD4+CD25- T cells, which manifests as increased proliferation/reduced suppression. Time-course experiments showed that this difference could be explained by higher IL-2 production from CD4+CD25low compared to CD4+CD25- T cells. There was also a significant increase in CD4+CD25low T-cell proliferation compared to CD4+CD25- T cells during suppression assays from RO T1D and at-risk subjects (n?=?28, p?=?0.015 and p?=?0.024 respectively). Conclusions/Significance The in vitro dual suppression assays proposed here could highlight the impaired sensitivity of certain responder T cells to the suppressive effect of Tregs in human autoimmune diseases. PMID:21151941

  10. SOCS3 Deletion in T-Lymphocytes Suppresses Development of Chronic Ocular Inflammation Via Up-regulation of CTLA-4 and Expansion of Regulatory T cells

    PubMed Central

    Yu, Cheng-Rong; Kim, Sung-Hye; Mahdi, Rashid M.; Egwuagu, Charles E.

    2013-01-01

    Suppressors of cytokine signaling (SOCS) proteins are negative-feedback regulators of JAK/STAT pathway and SOCS3 contributes to host immunity by regulating the intensity/duration of cytokine signals and inflammatory responses. Mice with Socs3 deletion in myeloid cells exhibit enhanced STAT3-signaling, expansion of Th1 and Th17 cells and developed severe experimental autoimmune encephalomyelitis (EAE). Interestingly, development of the unique IL-17/IFN-?-double producing (Th17/IFN-? and Tc17/IFN-?) subsets that exhibit strong cytotoxic activities and associated with pathogenesis of several autoimmune diseases, has recently been shown to depend on epigenetic suppression of SOCS3 expression, further suggesting involvement of SOCS3 in autoimmunity and tumor immunity. In this study, we generated mice with Socs3 deletion in CD4 T cell compartment (CD4-SOCS3KO) to determine in vivo effects of the loss of Socs3 in the T cell-mediated autoimmune disease, experimental autoimmune uveitis (EAU). In contrast to the exacerbation of EAE in myeloid-specific SOCS3-deleted mice, CD4-SOCS3KO mice were protected from acute and chronic uveitis. Protection from EAU correlated with enhanced expression of CTLA4 and expansion of IL-10 producing Tregs with augmented suppressive activities. We further show that SOCS3 interacts with CTLA4 and negatively regulates CTLA4 levels in T cells, providing mechanistic explanation for the expansion of Tregs in CD4-SOCS3 during EAU. Contrary to in vitro epigenetic studies, Th17/IFN-? and Tc17/IFN-? populations were markedly reduced in CD4-SOCS3KO, suggesting that SOCS3 promotes expansion of Th17/IFN-? subset associated with development of severe uveitis. Thus, SOCS3 is a potential therapeutic target in uveitis and other auto-inflammatory diseases. PMID:24101549

  11. T cell proliferation induced by anti-self-I-A-specific T cell hybridomas. Evidence of a T cell network

    PubMed Central

    1986-01-01

    Allo-I-A-reactive T cell hybridomas were generated from MLR-activated lymphoblasts. Cloned hybridomas T1.203, T1.321, and T1.426 were stimulated by I-Ab determinants, as shown by their ability to secrete IL-2 in response to a panel of MHC-recombinant mice. T2.146, T2.205, and T3.116 were found to be specific for I-Ak determinants using a similar panel of MHC-recombinant mice. Inhibition of IL-2 secretion by anti-I-A mAb confirmed these data. Some I-Ab-specific hybrids stimulated the proliferation of T cells from C57BL/6 (H-2b) mice. Similarly, some I-Ak-specific hybrids stimulated the proliferation of T cells from C3H/HeJ (H-2k) mice. These hybrids expressed no detectable surface I-A, and stimulation of T cells was not inhibited by anti-I-A mAb. These results are consistent with the hypothesis that normal mice possess a population of T cells responsive to idiotypic determinants on anti-MHC class II T cell receptors. PMID:3487615

  12. Harnessing the antibacterial and immunological properties of mucosal-associated invariant T cells in the development of novel oral vaccines against enteric infections.

    PubMed

    Abautret-Daly, Aine E; Davitt, Christopher J H; Lavelle, Ed C

    2014-11-15

    Enteric infections are a major cause of mortality and morbidity with significant social and economic implications worldwide and particularly in developing countries. An attractive approach to minimizing the impact of these diseases is via the development of oral vaccination strategies. However, oral vaccination is challenging due to the tolerogenic and hyporesponsive nature of antigen presenting cells resident in the gastrointestinal tract. The inclusion of adjuvants in oral vaccine formulations has the potential to overcome this challenge. To date no oral adjuvants have been licenced for human use and thus oral adjuvant discovery remains a key goal in improving the potential for oral vaccine development. Mucosal-associated invariant T (MAIT) cells are a recently discovered population of unconventional T cells characterized by an evolutionarily conserved ?? T cell receptor (TCR) that recognizes antigens presented by major histocompatibility complex (MHC) class I-related (MR1) molecule. MAIT cells are selected intra-thymically by MR1 expressing double positive thymocytes and enter the circulation with a naïve phenotype. In the circulation they develop a memory phenotype and are programmed to home to mucosal tissues and the liver. Once resident in these tissues, MAIT cells respond to bacterial and yeast infections through the production of chemokines and cytokines that aid in the induction of an adaptive immune response. Their abundance in the gastrointestinal tract and ability to promote adaptive immunity suggests that MAIT cell activators may represent attractive novel adjuvants for use in oral vaccination. PMID:25173989

  13. Transnuclear Mice with Pre-defined T Cell Receptor Specificities Against Toxoplasma gondii Obtained via SCNT

    E-print Network

    Suh, Heikyung

    Mice that are transgenic for rearranged antigen-specific T cell receptors (TCRs) are essential tools to study T cell development and function. Such TCRs are usually isolated from the relevant T cells after long-term culture, ...

  14. Regulation of natural killer activity of lymphocytes from normal subjects and patients with chronic lymphatic leukemia by interaction between T and non-T cells

    SciTech Connect

    Khonina, N.A.; Shubinskii, G.Z.; Lozovoi, V.P.

    1987-08-01

    The authors study the effect of culture of human cells on functional activity of natural killer cells and investigate the possible mechanisms of regulation of natural killer activity by acting on cytodifferentiation of lymphocytes in normal subjects and in patients with the B-cell variant of chromic lymphatic leukemia. To estimate natural killer cell function, a membranotoxic test was carried out, using cells of the transplantable line K-562, labeled with /sup 3/H-uridine as the targets.

  15. Shifting the Evolving CAR T Cell Platform into Higher Gear.

    PubMed

    Holohan, Daniel R; Lee, James C; Bluestone, Jeffrey A

    2015-10-12

    In this issue of Cancer Cell, Zhao and colleagues test various chimeric antigen receptor (CAR) T cells to show that CD28-CD3? CAR T cells that constitutively express 4-1BBL promote T cell expansion and tumor eradication while reducing exhaustion. The results have important implications for the development of effective CAR T cell therapies in cancer patients. PMID:26461084

  16. Immune system modelling: competition and T cell repertoire maintenance

    E-print Network

    Wirosoetisno, Djoko

    background thymus lymph nodes lymphoid vessels (tonsils) thymus + bone marrow = central lymphoid organs lymph nodes + lymphoid vessels = peripheral lymphoid organs bone marrow T cell development 1 Precursor T cells-reactive thymocytes are forced to die. 5 Mature T cells recirculate peripheral lymph tissues, where they encounter

  17. Engineered T cells for cancer treatment

    PubMed Central

    Anurathapan, Usanarat; Leen, Ann M.; Brenner, Malcolm K.; Vera, Juan F.

    2014-01-01

    Adoptively transferred T cells have the capacity to traffic to distant tumor sites, infiltrate even fibrotic tissue and kill antigen-expressing tumor cells. A variety of groups have investigated different genetic engineering strategies designed to enhance tumor specificity, increase T cell potency, improve proliferation, persistence, or migratory capacity, and increase safety. In this review we focus on recent developments in the T cell engineering arena, discuss the application of these engineered cell products clinically, and outline future prospects for this therapeutic modality. PMID:24239105

  18. Breaking the co-operation between bystander T-cells and natural killer cells prevents the development of immunosuppression after traumatic skeletal muscle injury in mice.

    PubMed

    Wirsdörfer, Florian; Bangen, Jörg M; Pastille, Eva; Hansen, Wiebke; Flohé, Stefanie B

    2015-06-01

    Nosocomial infections represent serious complications after traumatic or surgical injuries in intensive care units. The pathogenesis of the underlying immunosuppression is only incompletely understood. In the present study, we investigated whether injury interferes with the function of the adaptive immune system in particular with the differentiation of antigen-specific T helper (Th)-cell responses in vivo. We used a mouse model for traumatic gastrocnemius muscle injury. Ovalbumin (OVA), which served as a foreign model antigen, was injected into the hind footpads for determination of the differentiation of OVA-specific Th-cells in the draining popliteal lymph node (pLN). The release of interferon (IFN)-? from OVA-specific Th-cells was impaired within 24 h after injury and this impairment persisted for at least 7 days. In contrast, the proliferation of OVA-specific Th-cells remained unaffected. Injury did not modulate the function of antigen-presenting cells (APCs) in the pLN. Adoptive transfer of total T-cells from pLNs of injured mice inhibited IFN-? production by OVA-specific Th-cells in naive mice. Suppressed Th1 priming did not occur in lymphocyte-deficient mice after injury but was restored by administration of T-cells before injury. Moreover, the suppression of Th1 differentiation required the presence of natural killer (NK) cells that were recruited to the pLN after injury; this recruitment was dependent on lymphocytes, toll-like receptor 4 (TLR4) and myeloid differentiation factor 88 (MyD88). In summary, upon traumatic skeletal muscle injury T-cells and NK cells together prevent the development of protective Th1 immunity. Breaking this co-operation might be a novel approach to reduce the risk of infectious complications after injury. PMID:25609031

  19. Breaking the co-operation between bystander T-cells and natural killer cells prevents the development of immunosuppression after traumatic skeletal muscle injury in mice

    PubMed Central

    Wirsdörfer, Florian; Bangen, Jörg M.; Pastille, Eva; Hansen, Wiebke

    2015-01-01

    Nosocomial infections represent serious complications after traumatic or surgical injuries in intensive care units. The pathogenesis of the underlying immunosuppression is only incompletely understood. In the present study, we investigated whether injury interferes with the function of the adaptive immune system in particular with the differentiation of antigen-specific T helper (Th)-cell responses in vivo. We used a mouse model for traumatic gastrocnemius muscle injury. Ovalbumin (OVA), which served as a foreign model antigen, was injected into the hind footpads for determination of the differentiation of OVA-specific Th-cells in the draining popliteal lymph node (pLN). The release of interferon (IFN)-? from OVA-specific Th-cells was impaired within 24 h after injury and this impairment persisted for at least 7 days. In contrast, the proliferation of OVA-specific Th-cells remained unaffected. Injury did not modulate the function of antigen-presenting cells (APCs) in the pLN. Adoptive transfer of total T-cells from pLNs of injured mice inhibited IFN-? production by OVA-specific Th-cells in naive mice. Suppressed Th1 priming did not occur in lymphocyte-deficient mice after injury but was restored by administration of T-cells before injury. Moreover, the suppression of Th1 differentiation required the presence of natural killer (NK) cells that were recruited to the pLN after injury; this recruitment was dependent on lymphocytes, toll-like receptor 4 (TLR4) and myeloid differentiation factor 88 (MyD88). In summary, upon traumatic skeletal muscle injury T-cells and NK cells together prevent the development of protective Th1 immunity. Breaking this co-operation might be a novel approach to reduce the risk of infectious complications after injury. PMID:25609031

  20. Physical Development: What's Normal? What's Not?

    MedlinePLUS

    ... Development: What’s Normal? What’s Not? Article Body ?Two boys or girls exactly the same age can start or end ... in Girls: What to Expect . Growth in both boys and girls slows considerably soon after puberty is complete. Having ...

  1. Bacterial clearance reverses a skewed T-cell repertoire induced by Salmonella infection

    PubMed Central

    Leyva-Rangel, Jessica P; de los Angeles Hernández-Cueto, Maria; Galan-Enriquez, Carlos-Samuel; López-Medina, Marcela; Ortiz-Navarrete, Vianney

    2015-01-01

    Salmonella typhimurium invades the spleen, liver, and peripheral lymph nodes and has recently been detected in the bone marrow and thymus, resulting in a reduced thymic size and a decline in the total number of thymic cells. A specific deletion of the double-positive cell subset has been characterized, yet the export of mature T cells to the periphery remains normal. We analyzed Salmonella pathogenesis regarding thymic structure and the T-cell maturation process. We demonstrate that, despite alterations in the thymic structure, T-cell development is maintained during Salmonella infection, allowing the selection of single-positive T-cell clones expressing particular T-cell receptor beta chains (TCR-V?). Moreover, the treatment of infected mice with an antibiotic restored the normal thymic architecture and thymocyte subset distribution. Additionally, the frequency of TCR-V? usage after treatment was comparable to that in non-infected mice. However, bacteria were still recovered from the thymus after 1 month of treatment. Our data reveal that a skewed T-cell developmental process is present in the Salmonella-infected thymus that alters the TCR-V? usage frequency. Likewise, the post-treatment persistence of Salmonella reveals a novel function of the thymus as a potential reservoir for this infectious agent. PMID:26417438

  2. T Cell Epitope Mapping of JC Polyoma Virus-Encoded Proteome Reveals Reduced T Cell Responses in HLA-DRB1*04:01+ Donors

    PubMed Central

    Jel?i?, Ilijas; Aly, Lilian; Binder, Thomas M. C.; Jel?i?, Ivan; Bofill-Mas, Sílvia; Planas, Raquel; Demina, Victoria; Eiermann, Thomas H.; Weber, Thomas; Girones, Rosina; Sospedra, Mireia

    2013-01-01

    JC polyomavirus (JCV) infection is highly prevalent and usually kept in a persistent state without clinical signs and symptoms. It is only during immunocompromise and especially impaired CD4+ T cell function in the brain, as seen in AIDS patients or natalizumab-treated multiple sclerosis patients, that JCV may cause progressive multifocal leukoencephalopathy (PML), an often life-threatening brain disease. Since CD4+ T cells likely play an important role in controlling JCV infection, we here describe the T cell response to JCV in a group of predominantly HLA-DR-heterozygotic healthy donors (HD) by using a series of overlapping 15-mer peptides spanning all JCV-encoded open reading frames. We identified immunodominant epitopes and compared T cell responses with anti-JCV VP1 antibody production and with the presence of urinary viral shedding. We observed positive JCV-specific T cell responses in 28.6% to 77.6%, humoral immune response in 42.6% to 89.4%, and urinary viral shedding in 36.4% to 45.5% of HD depending on the threshold. Four immunodominant peptides were mapped, and at least one immunogenic peptide per HLA-DRB1 allele was detected in DRB1*01+, DRB1*07+, DRB1*11+, DRB1*13+, DRB1*15+, and DRB1*03+ individuals. We show for the first time that JCV-specific T cell responses may be directed not only against JCV VP1 and large T antigen but also against all other JCV-encoded proteins. Heterozygotic DRB1*04:01+ individuals showed very low T cell responses to JCV together with normal anti-VP1 antibody levels and no urinary viral shedding, indicating a dominant-negative effect of this allele on global JCV-directed T cell responses. Our data are potentially relevant for the development of vaccines against JCV. PMID:23302880

  3. Increased Interleukin-4 production by CD8 and gammadelta T cells in health-care workers is associated with the subsequent development of active tuberculosis.

    PubMed

    Ordway, Diane J; Costa, Leonor; Martins, Marta; Silveira, Henrique; Amaral, Leonard; Arroz, Maria J; Ventura, Fernando A; Dockrell, Hazel M

    2004-08-15

    We evaluated immune responses to Mycobacterium tuberculosis in 10 health-care workers (HCWs) and 10 non-HCWs and correlated their immune status with the development of active tuberculosis (TB). Twenty individuals were randomly recruited, tested, and monitored longitudinally for TB presentation. Peripheral blood mononuclear cells (PBMCs) from donors were stimulated with M. tuberculosis and tested for cell proliferation and the production of interferon (IFN)- gamma, interleukin (IL)-5, and IL-4, by use of enzyme-linked immunosorbent or flow-cytometric assays. HCWs had higher levels of cell proliferation (24,258 cpm) and IFN- gamma (6373 pg/mL) to M. tuberculosis than did non-HCWs (cell proliferation, 11,462 cpm; IFN- gamma, 3228 pg/mL). Six of 10 HCWs showed increased median percentages of CD8+IL-4+ (4.7%) and gammadelta +IL-4+ (2.3%) T cells and progressed to active TB. HCWs who remained healthy showed increased median percentages of CD8+IFN- gamma+ (25.0%) and gammadelta +IFN- gamma+ (8.0%) and lower percentages of CD8+IL-4+ (0.05%) and gammadelta +IL-4+ (0.03%) T cells. PMID:15272404

  4. The PIAS-like Coactivator Zmiz1 Is a Direct and Selective Cofactor of Notch1 in T Cell Development and Leukemia.

    PubMed

    Pinnell, Nancy; Yan, Ran; Cho, Hyo Je; Keeley, Theresa; Murai, Marcelo J; Liu, Yiran; Alarcon, Amparo Serna; Qin, Jason; Wang, Qing; Kuick, Rork; Elenitoba-Johnson, Kojo S J; Maillard, Ivan; Samuelson, Linda C; Cierpicki, Tomasz; Chiang, Mark Y

    2015-11-17

    Pan-NOTCH inhibitors are poorly tolerated in clinical trials because NOTCH signals are crucial for intestinal homeostasis. These inhibitors might also promote cancer because NOTCH can act as a tumor suppressor. We previously reported that the PIAS-like coactivator ZMIZ1 is frequently co-expressed with activated NOTCH1 in T cell acute lymphoblastic leukemia (T-ALL). Here, we show that similar to Notch1, Zmiz1 was important for T cell development and controlled the expression of certain Notch target genes, such as Myc. However, unlike Notch, Zmiz1 had no major role in intestinal homeostasis or myeloid suppression. Deletion of Zmiz1 impaired the initiation and maintenance of Notch-induced T-ALL. Zmiz1 directly interacted with Notch1 via a tetratricopeptide repeat domain at a special class of Notch-regulatory sites. In contrast to the Notch cofactor Maml, which is nonselective, Zmiz1 was selective. Thus, targeting the NOTCH1-ZMIZ1 interaction might combat leukemic growth while avoiding the intolerable toxicities of NOTCH inhibitors. PMID:26522984

  5. Genetic Analysis of T Cell Lymphomas in Carbon Ion-Irradiated Mice Reveals Frequent Interstitial Chromosome Deletions: Implications for Second Cancer Induction in Normal Tissues during Carbon Ion Radiotherapy

    PubMed Central

    Blyth, Benjamin J.; Kakinuma, Shizuko; Sunaoshi, Masaaki; Amasaki, Yoshiko; Hirano-Sakairi, Shinobu; Ogawa, Kanae; Shirakami, Ayana; Shang, Yi; Tsuruoka, Chizuru; Nishimura, Mayumi; Shimada, Yoshiya

    2015-01-01

    Monitoring mice exposed to carbon ion radiotherapy provides an indirect method to evaluate the potential for second cancer induction in normal tissues outside the radiotherapy target volume, since such estimates are not yet possible from historical patient data. Here, male and female B6C3F1 mice were given single or fractionated whole-body exposure(s) to a monoenergetic carbon ion radiotherapy beam at the Heavy Ion Medical Accelerator in Chiba, Japan, matching the radiation quality delivered to the normal tissue ahead of the tumour volume (average linear energy transfer = 13 keV.?m-1) during patient radiotherapy protocols. The mice were monitored for the remainder of their lifespan, and a large number of T cell lymphomas that arose in these mice were analysed alongside those arising following an equivalent dose of 137Cs gamma ray-irradiation. Using genome-wide DNA copy number analysis to identify genomic loci involved in radiation-induced lymphomagenesis and subsequent detailed analysis of Notch1, Ikzf1, Pten, Trp53 and Bcl11b genes, we compared the genetic profile of the carbon ion- and gamma ray-induced tumours. The canonical set of genes previously associated with radiation-induced T cell lymphoma was identified in both radiation groups. While the pattern of disruption of the various pathways was somewhat different between the radiation types, most notably Pten mutation frequency and loss of heterozygosity flanking Bcl11b, the most striking finding was the observation of large interstitial deletions at various sites across the genome in carbon ion-induced tumours, which were only seen infrequently in the gamma ray-induced tumours analysed. If such large interstitial chromosomal deletions are a characteristic lesion of carbon ion irradiation, even when using the low linear energy transfer radiation to which normal tissues are exposed in radiotherapy patients, understanding the dose-response and tissue specificity of such DNA damage could prove key to assessing second cancer risk in carbon ion radiotherapy patients. PMID:26125582

  6. I spy alloreactive T cells.

    PubMed

    Alegre, Maria-Luisa

    2015-01-28

    High-throughput sequencing of the T cell receptor V? CDR3 region allowed longitudinal tracking of alloreactive T cells in kidney transplant patients, revealing clonal deletion as a mechanism of transplantation tolerance (Morris et al., this issue). PMID:25632032

  7. A T-cell-directed chimeric antigen receptor for the selective treatment of T-cell malignancies.

    PubMed

    Mamonkin, Maksim; Rouce, Rayne H; Tashiro, Haruko; Brenner, Malcolm K

    2015-08-20

    Options for targeted therapy of T-cell malignancies remain scarce. Recent clinical trials demonstrated that chimeric antigen receptors (CARs) can effectively redirect T lymphocytes to eradicate lymphoid malignancies of B-cell origin. However, T-lineage neoplasms remain a more challenging task for CAR T cells due to shared expression of most targetable surface antigens between normal and malignant T cells, potentially leading to fratricide of CAR T cells or profound immunodeficiency. Here, we report that T cells transduced with a CAR targeting CD5, a common surface marker of normal and neoplastic T cells, undergo only limited fratricide and can be expanded long-term ex vivo. These CD5 CAR T cells effectively eliminate malignant T-cell acute lymphoblastic leukemia (T-ALL) and T-cell lymphoma lines in vitro and significantly inhibit disease progression in xenograft mouse models of T-ALL. These data support the therapeutic potential of CD5 CAR in patients with T-cell neoplasms. PMID:26056165

  8. Developmentally determined reduction in CD31 during gestation is associated with CD8+ T cell effector differentiation in preterm infants.

    PubMed

    Scheible, Kristin M; Emo, Jason; Yang, Hongmei; Holden-Wiltse, Jeanne; Straw, Andrew; Huyck, Heidie; Misra, Sara; Topham, David J; Ryan, Rita M; Reynolds, Anne Marie; Mariani, Thomas J; Pryhuber, Gloria S

    2015-12-01

    Homeostatic T cell proliferation is more robust during human fetal development. In order to understand the relative effect of normal fetal homeostasis and perinatal exposures on CD8+ T cell behavior in PT infants, we characterized umbilical cord blood CD8+ T cells from infants born between 23-42weeks gestation. Subjects were recruited as part of the NHLBI-sponsored Prematurity and Respiratory Outcomes Program. Cord blood from PT infants had fewer naïve CD8+ T cells and lower regulatory CD31 expression on both naïve and effector, independent of prenatal exposures. CD8+ T cell in vitro effector function was greater at younger gestational ages, an effect that was exaggerated in infants with prior inflammatory exposures. These results suggest that CD8+ T cells earlier in gestation have loss of regulatory co-receptor CD31 and greater effector differentiation, which may place PT neonates at unique risk for CD8+ T cell-mediated inflammation and impaired T cell memory formation. PMID:26232733

  9. Identification of novel gammadelta T-cell subsets following bacterial infection in the absence of Vgamma1+ T cells: homeostatic control of gammadelta T-cell responses to pathogen infection by Vgamma1+ T cells.

    PubMed

    Newton, Darren J; Andrew, Elizabeth M; Dalton, Jane E; Mears, Rainy; Carding, Simon R

    2006-02-01

    Although gammadelta T cells are a common feature of many pathogen-induced immune responses, the factors that influence, promote, or regulate the response of individual gammadelta T-cell subsets to infection is unknown. Here we show that in the absence of Vgamma1+ T cells, novel subsets of gammadelta T cells, expressing T-cell receptor (TCR)-Vgamma chains that normally define TCRgammadelta+ dendritic epidermal T cells (DETCs) (Vgamma5+), intestinal intraepithelial lymphocytes (iIELs) (Vgamma7+), and lymphocytes associated with the vaginal epithelia (Vgamma6+), are recruited to the spleen in response to bacterial infection in TCR-Vgamma1-/- mice. By comparison of phenotype and structure of TCR-Vgamma chains and/or -Vdelta chains expressed by these novel subsets with those of their epithelium-associated counterparts, the Vgamma6+ T cells elicited in infected Vgamma1-/- mice were shown to be identical to those found in the reproductive tract, from where they are presumably recruited in the absence of Vgamma1+ T cells. By contrast, Vgamma5+ and Vgamma7+ T cells found in infected Vgamma1-/- mice were distinct from Vgamma5+ DETCs and Vgamma7+ iIELs. Functional analyses of the novel gammadelta T-cell subsets identified for infected Vgamma1-/- mice showed that whereas the Vgamma5+ and Vgamma7+ subsets may compensate for the absence of Vgamma1+ T cells by producing similar cytokines, they do not possess cytocidal activity and they cannot replace the macrophage homeostasis function of Vgamma1+ T cells. Collectively, these findings identify novel subsets of gammadelta T cells, the recruitment and activity of which is under the control of Vgamma1+ T cells. PMID:16428757

  10. A sharp T-cell antigen receptor signaling threshold for T-cell proliferation.

    PubMed

    Au-Yeung, Byron B; Zikherman, Julie; Mueller, James L; Ashouri, Judith F; Matloubian, Mehrdad; Cheng, Debra A; Chen, Yiling; Shokat, Kevan M; Weiss, Arthur

    2014-09-01

    T-cell antigen receptor (TCR) signaling is essential for activation, proliferation, and effector function of T cells. Modulation of both intensity and duration of TCR signaling can regulate these events. However, it remains unclear how individual T cells integrate such signals over time to make critical cell-fate decisions. We have previously developed an engineered mutant allele of the critical T-cell kinase zeta-chain-associated protein kinase 70 kDa (Zap70) that is catalytically inhibited by a small molecule inhibitor, thereby blocking TCR signaling specifically and efficiently. We have also characterized a fluorescent reporter Nur77-eGFP transgenic mouse line in which T cells up-regulate GFP uniquely in response to TCR stimulation. The combination of these technologies unmasked a sharp TCR signaling threshold for commitment to cell division both in vitro and in vivo. Further, we demonstrate that this threshold is independent of both the magnitude of the TCR stimulus and Interleukin 2. Similarly, we identify a temporal threshold of TCR signaling that is required for commitment to proliferation, after which T cells are able to proliferate in a Zap70 kinase-independent manner. Taken together, our studies reveal a sharp threshold for the magnitude and duration of TCR signaling required for commitment of T cells to proliferation. These results have important implications for understanding T-cell responses to infection and optimizing strategies for immunomodulatory drug delivery. PMID:25136127

  11. A sharp T-cell antigen receptor signaling threshold for T-cell proliferation

    PubMed Central

    Au-Yeung, Byron B.; Zikherman, Julie; Mueller, James L.; Ashouri, Judith F.; Matloubian, Mehrdad; Cheng, Debra A.; Chen, Yiling; Shokat, Kevan M.; Weiss, Arthur

    2014-01-01

    T-cell antigen receptor (TCR) signaling is essential for activation, proliferation, and effector function of T cells. Modulation of both intensity and duration of TCR signaling can regulate these events. However, it remains unclear how individual T cells integrate such signals over time to make critical cell-fate decisions. We have previously developed an engineered mutant allele of the critical T-cell kinase zeta-chain-associated protein kinase 70 kDa (Zap70) that is catalytically inhibited by a small molecule inhibitor, thereby blocking TCR signaling specifically and efficiently. We have also characterized a fluorescent reporter Nur77–eGFP transgenic mouse line in which T cells up-regulate GFP uniquely in response to TCR stimulation. The combination of these technologies unmasked a sharp TCR signaling threshold for commitment to cell division both in vitro and in vivo. Further, we demonstrate that this threshold is independent of both the magnitude of the TCR stimulus and Interleukin 2. Similarly, we identify a temporal threshold of TCR signaling that is required for commitment to proliferation, after which T cells are able to proliferate in a Zap70 kinase-independent manner. Taken together, our studies reveal a sharp threshold for the magnitude and duration of TCR signaling required for commitment of T cells to proliferation. These results have important implications for understanding T-cell responses to infection and optimizing strategies for immunomodulatory drug delivery. PMID:25136127

  12. ?? T Cells in HIV Disease: Past, Present, and Future

    PubMed Central

    Pauza, C. David; Poonia, Bhawna; Li, Haishan; Cairo, Cristiana; Chaudhry, Suchita

    2015-01-01

    Human immunodeficiency virus (HIV) type 1 dysregulates ?? T cells as part of an immune evasion mechanism. Nearly three decades of research defined the effects of HIV on ?? T cells and how this impacts disease. With highly effective antiretroviral therapy providing virus suppression and longer survival, we expected a return to normal for ?? T cells. This is not the case. Even in patients with CD4 T cell reconstitution, normal ?? T cell levels and function are not recovered. The durable damage to V?2 T cells is paralleled by defects in NK, CD8 T cells, and dendritic cells. Whether these consequences of HIV stem from similar or distinct mechanisms are not known and effective means for recovering the full range of cellular immunity have not been discovered. These unanswered questions receive too little attention in the overall program of efforts to cure HIV this disease. Approved drugs capable of increasing V?2 T cell function are being tested in clinical trials for cancer and hold promise for restoring normal function in patients with HIV disease. The impetus for conducting clinical trials will come from understanding the significance of ?? T cells in HIV disease and what might be gained from targeted immunotherapy. This review traces the history and current progress of AIDS-related research on ?? T cells. We emphasize the damage to ?? T cells that persists despite effective virus suppression. These chronic immune deficits may be linked to the comorbidities of AIDS (cancer, cardiovascular disease, metabolic disease, and others) and will hinder efforts to eradicate HIV by cytotoxic T or NK cell killing. Here, we focus on one subset of T cells that may be critical in the pathogenesis of HIV and an attractive target for new immune-based therapies. PMID:25688241

  13. PTPN2 attenuates T-cell lymphopenia-induced proliferation

    NASA Astrophysics Data System (ADS)

    Wiede, Florian; La Gruta, Nicole L.; Tiganis, Tony

    2014-01-01

    When the peripheral T-cell pool is depleted, T cells undergo homoeostatic expansion. This expansion is reliant on the recognition of self-antigens and/or cytokines, in particular interleukin-7. The T cell-intrinsic mechanisms that prevent excessive homoeostatic T-cell responses and consequent overt autoreactivity remain poorly defined. Here we show that protein tyrosine phosphatase N2 (PTPN2) is elevated in naive T cells leaving the thymus to restrict homoeostatic T-cell proliferation and prevent excess responses to self-antigens in the periphery. PTPN2-deficient CD8+ T cells undergo rapid lymphopenia-induced proliferation (LIP) when transferred into lymphopenic hosts and acquire the characteristics of antigen-experienced effector T cells. The enhanced LIP is attributed to elevated T-cell receptor-dependent, but not interleukin-7-dependent responses, results in a skewed T-cell receptor repertoire and the development of autoimmunity. Our results identify a major mechanism by which homoeostatic T-cell responses are tuned to prevent the development of autoimmune and inflammatory disorders.

  14. Memory T Cells in Transplantation

    PubMed Central

    Su, Charles A.; Fairchild, Robert L.

    2014-01-01

    Following infections and environmental exposures, memory T cells are generated that provide long-term protective immunity. Compared to their naïve T cell counterparts, memory T cells possess unique characteristics that endow them with the ability to quickly and robustly respond to foreign antigens. While such memory T cells are beneficial in protecting their hosts from recurrent infection, memory cells reactive to donor antigens pose a major barrier to successful transplantation and tolerance induction. Significant progress has been made over the past several decades contributing to our understanding of memory T cell generation, their distinct biology, and their detrimental impact in clinical and animal models of transplantation. This review focuses on the unique features which make memory T cells relevant to the transplant community and discusses potential therapies targeting memory T cells which may ameliorate allograft rejection. PMID:25435071

  15. Self-recognition specificity expressed by T cells from nude mice. Absence of detectable Ia-restricted T cells in nude mice that do exhibit self-K/D-restricted T cell responses

    SciTech Connect

    Kruisbeek, A.M.; Davis, M.L.; Matis, L.A.; Longo, D.L.

    1984-09-01

    The presence in athymic nude mice of precursor T cells with self-recognition specificity for either H-2 K/D or H-2 I region determinants was investigated. Chimeras were constructed of lethally irradiated parental mice receiving a mixture of F1 nude mouse (6-8 wk old) spleen and bone marrow cells. The donor inoculum was deliberately not subjected to any T cell depletion procedure, so that any potential major histocompatibility complex-committed precursor T cells were allowed to differentiate and expand in the normal parental recipients. 3 mo after reconstitution, the chimeras were immunized with several protein antigens in complete Freund's adjuvant in the footpads and their purified draining lymph node T cells tested 10 d later for ability to recognize antigen on antigen-presenting cells of either parental haplotype. Also, their spleen and lymph node cells were tested for ability to generate a cytotoxic T lymphocyte (CTL) response to trinitrophenyl (TNP)-modified stimulator cells of either parental haplotype. It was demonstrated that T cell proliferative responses of these F1(nude)----parent chimeras were restricted solely to recognizing parental host I region determinants as self and expressed the Ir gene phenotype of the host. In contrast, CTL responses could be generated (in the presence of interleukin 2) to TNP-modified stimulator cells of either parental haplotype. Thus these results indicate that nude mice which do have CTL with self-specificity for K/D region determinants lack proliferating T cells with self-specificity for I region determinants. These results provide evidence for the concepts that development of the I region-restricted T cell repertoire is strictly an intrathymically determined event and that young nude mice lack the unique thymic elements responsible for edu

  16. Ganglioside-exposed dendritic cells inhibit T-cell effector function by promoting regulatory cell activity.

    PubMed

    Jales, Alessandra; Falahati, Rustom; Mari, Elisabeth; Stemmy, Erik J; Shen, Weiping; Southammakosane, Cathy; Herzog, Dallen; Ladisch, Stephan; Leitenberg, David

    2011-01-01

    Tumour pathogenesis is characterized by an immunosuppressive microenvironment that limits the development of effective tumour-specific immune responses. This is in part the result of tumour-dependent recruitment and activation of regulatory cells, such as myeloid-derived suppressor cells and regulatory T cells in the tumour microenvironment and draining lymph nodes. Shedding of gangliosides by tumour cells has immunomodulatory properties, suggesting that gangliosides may be a critical factor in initiating an immunosuppressive microenvironment. To better define the immunomodulatory properties of gangliosides on antigen-specific T-cell activation and development we have developed an in vitro system using ganglioside-treated murine bone-marrow-derived dendritic cells to prime and activate antigen-specific CD4(+) T cells from AND T-cell receptor transgenic mice. Using this system, ganglioside treatment promotes the development of a dendritic cell population characterized by decreased CD86 (B7-2) expression, and decreased interleukin-12 and interleukin-6 production. When these cells are used as antigen-presenting cells, CD4 T cells are primed to proliferate normally, but have a defect in T helper (Th) effector cell development. This defect in Th effector cell responses is associated with the development of regulatory T-cell activity that can suppress the activation of previously primed Th effector cells in a contact-dependent manner. In total, these data suggest that ganglioside-exposed dendritic cells promote regulatory T-cell activity that may have long-lasting effects on the development of tumour-specific immune responses. PMID:20875076

  17. Contrasting Roles For All-Trans Retinoic Acid in TGF-ß-mediated Induction of Foxp3 and Il10 Genes in Developing Regulatory T Cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extrathymic induction of regulatory T cells (Treg) is essential to the regulation of effector T cell responses in the periphery. TGF-ß has been shown to induce Foxp3-expressing Tregs both in vitro and in vivo. More recently, the vitamin A metabolite, all-trans retinoic acid (at-RA), has been found t...

  18. : TLR4 signaling in effector CD4+ T cells regulates TCR activation and

    E-print Network

    Huang, Ching-Tsan

    /2 TCR ERK1/2 TCR KeywordsTLRsCD4+ T cellsTCRERKMAPKMKP-3 IL-10 [1] inflammatory bowel disease in enhanced T cell responses but normal innate responses to lipopolysaccharide or skin irritation. J Exp Med

  19. Recent Developments in Nonlinear Normal Mode Initialization

    NASA Technical Reports Server (NTRS)

    Bloom, S. C.

    1985-01-01

    The importance of a balanced initial condition upon GLAS GCM forecasts and assimilation cycles was assessed. An effort to combine previous work on normal mode initialization at GLA is underway to develop an initialization process for the production version of the GLAS 4th order GCM. The major aspects of this work fall into two parts: vectorization of the linear projector code and the insertion of the mode projector and Machenhauer iteration algorithm into the full GLAS GCM. Memory and paging constraints place restrictions on the number of horizontal modes stored for initialization purposes, and on the manner in which they are stored. Only the first five vertical structures of the gravity modes are used. Differing phase and normalization conventions provided many elusive coding errors. A Machenhauer nonlinear normal mode initialization technique is used. This method entails the insertion of a modified version of the mode projector into the full GCM, and the modification of the GCM to allow for iterative calls to the projector.

  20. T cell dysfunction in the diabetes-prone BB rat. A role for thymic migrants that are not T cell precursors

    SciTech Connect

    Georgiou, H.M.; Lagarde, A.C.; Bellgrau, D.

    1988-01-01

    Diabetes-prone BB (BB-DP) rats express several T cell dysfunctions which include poor proliferative and cytotoxic responses to alloantigen. The goal of this study was to determine the origin of these T cell dysfunctions. When BB-DP rats were thymectomized, T cell depleted, and transplanted with neonatal thymus tissue from diabetes-resistant and otherwise normal DA/BB F1 rats, the early restoration of T cell function proceeded normally on a cell-for-cell basis; i.e., peripheral T cells functioned like those from the thymus donor. Because the thymus in these experiments was subjected to gamma irradiation before transplantation and there was no evidence of F1 chimerism in the transplanted BB-DP rats, it appeared that the BB-DP T cell precursors could mature into normally functioning T cells if the maturation process occurred in a normal thymus. If the F1 thymus tissue was treated with dGua before transplantation, the T cells of these animals functioned poorly like those from untreated BB-DP rats. dGua poisons bone marrow-derived cells, including gamma radiation-resistant cells of the macrophage/dendritic cell lineages, while sparing the thymic epithelium. Therefore, the reversal of the T cell dysfunction depends on the presence in the F1 thymus of gamma radiation-resistant, dGua-sensitive F1 cells. Conversely, thymectomized and T cell-depleted F1 rats expressed T cell dysfunction when transplanted with gamma-irradiated BB thymus grafts. T cell responses were normal in animals transplanted with dGua-treated BB thymus grafts. With increasing time after thymus transplantation, T cells from all animals gradually expressed the functional phenotype of the bone marrow donor. Taken together these results suggest that BB-DP bone marrow-derived cells that are not T cell precursors influence the maturation environment in the thymus of otherwise normal BB-DP T cell precursors.

  1. Cell-autonomous requirement for TCF1 and LEF1 in the development of Natural Killer T cells.

    PubMed

    Berga-Bolaños, Rosa; Zhu, Wandi S; Steinke, Farrah C; Xue, Hai-Hui; Sen, Jyoti Misra

    2015-12-01

    Natural killer T (NKT) cells develop from common CD4(+) CD8(+) thymocyte precursors. Transcriptional programs that regulate the development of NKT cells in the thymus development remain to be fully delineated. Here, we demonstrate a cell-intrinsic requirement for transcription factors TCF1 and LEF1 for the development of all subsets of NKT cells. Conditional deletion of TCF1 alone results in a substantial reduction in NKT cells. The remaining NKT cells are eliminated when TCF1 and LEF1 are both deleted. These data reveal an essential role for TCF1 and LEF1 in development of NKT cells. PMID:26490636

  2. Regulatory T cells in infection.

    PubMed

    Maizels, Rick M; Smith, Katherine A

    2011-01-01

    Infectious agents have intimately co-evolved with the host immune system, acquiring a portfolio of highly sophisticated mechanisms to modulate immunity. Among the common strategies developed by viruses, bacteria, protozoa, helminths, and fungi is the manipulation of the regulatory T cell network in order to favor pathogen survival and transmission. Treg activity also benefits the host in many circumstances by controlling immunopathogenic reactions to infection. Interestingly, some pathogens are able to directly induce the conversion of naive T cells into suppressive Foxp3-expressing Tregs, while others activate pre-existing natural Tregs, in both cases repressing pathogen-specific effector responses. However, Tregs can also act to promote immunity in certain settings, such as in initial stages of infection when effector cells must access the site of infection, and subsequently in ensuring generation of effector memory. Notably, there is little current information on whether infections selectively drive pathogen-specific Tregs, and if so whether these cells are also reactive to self-antigens. Further analysis of specificity, together with a clearer picture of the relative dynamics of Treg subsets over the course of disease, should lead to rational strategies for immune intervention to optimize immunity and eliminate infection. PMID:22118407

  3. Mouse Naïve CD4+ T Cell Isolation and In vitro Differentiation into T Cell Subsets.

    PubMed

    Flaherty, Stephanie; Reynolds, Joseph M

    2015-01-01

    Antigen inexperienced (naïve) CD4(+) T cells undergo expansion and differentiation to effector subsets at the time of T cell receptor (TCR) recognition of cognate antigen presented on MHC class II. The cytokine signals present in the environment at the time of TCR activation are a major factor in determining the effector fate of a naïve CD4(+) T cell. Although the cytokine environment during naïve T cell activation may be complex and involve both redundant and opposing signals in vivo, the addition of various cytokine combinations during naive CD4(+) T cell activation in vitro can readily promote the establishment of effector T helper lineages with hallmark cytokine and transcription factor expression. Such differentiation experiments are commonly used as a first step for the evaluation of targets believed to promote or inhibit the development of certain CD4(+) T helper subsets. The addition of mediators, such as signaling agonists, antagonists, or other cytokines, during the differentiation process can also be used to study the influence of a particular target on T cell differentiation. Here, we describe a basic protocol for the isolation of naïve T cells from mouse and the subsequent steps necessary for polarizing naïve cells to various T helper effector lineages in vitro. PMID:25938923

  4. Immunophenotypic and antigen receptor gene rearrangement analysis in T cell neoplasia.

    PubMed Central

    Knowles, D. M.

    1989-01-01

    The author reviews the immunophenotypic profiles displayed by the major clinicopathologic categories of T cell neoplasia, the immunophenotypic criteria useful in the immunodiagnosis of T cell neoplasia, and the contributions made by antigen receptor gene rearrangement analysis to the understanding of T cell neoplasia. Neoplasms belonging to distinct clinicopathologic categories of T cell neoplasia often exhibit characteristic immunophenotypic profiles. Approximately 80% of lymphoblastic lymphomas and 20% of acute lymphoblastic leukemias express phenotypes consistent with prethymic and intrathymic stages of T cell differentiation, including intranuclear terminal deoxynucleotidyl transferase. Cutaneous T cell lymphomas of mycosis fungoides type usually express pan-T cell antigens CD2, CD5, and CD3, often lack the pan-T cell antigen CD7, and usually express the mature, peripheral helper subset phenotype, CD4+ CD8-. Cutaneous T cell lymphomas of nonmycosis fungoides type and peripheral T cell lymphomas often lack one or more pan-T cell antigens and, in addition, occasionally express the anomalous CD4+ CD8+ or CD4- CD8- phenotypes. T gamma-lymphoproliferative disease is divisable into two broad categories: those cases that are CD3 antigen positive and exhibit clonal T cell receptor beta chain (TCR-beta) gene rearrangements and those cases that are CD3 antigen negative and exhibit the TCR-beta gene germline configuration. Human T cell lymphotropic virus-I (HTLV-I) associated Japanese, Carribean, and sporadic adult T cell leukemia/lymphomas usually express pan-T cell antigens, the CD4+ CD8- phenotype, and various T cell-associated activation antigens, including the interleukin-2 receptor (CD25). Immunophenotypic criteria useful in the immunodiagnosis of T cell neoplasia include, in increasing order of utility, T cell predominance, T cell subset antigen restriction, anomalous T cell subset antigen expression, and deletion of one or more pan-T cell antigens. Only in exceptional circumstances do normal, non-neoplastic T cell populations express the CD4- CD8- or the CD4+ CD8+ phenotype and/or lack one or more pan-T cell antigens. T cell receptor beta chain gene rearrangement analysis represents an accurate, objective, and sensitive molecular genetic marker of T cell lineage and clonality that allows discrimination among non-T cell, polyclonal T cell and monoclonal T cell populations. Non-T cells exhibit the TCR-beta gene germline configuration.(ABSTRACT TRUNCATED AT 400 WORDS) Images Figure 3 Figure 6 Figure 7 PMID:2495724

  5. TCRV?9 ?? T Cell Response to IL-33: A CD4 T Cell-Dependent Mechanism.

    PubMed

    Duault, Caroline; Franchini, Don Marc; Familliades, Julien; Cayrol, Corinne; Roga, Stéphane; Girard, Jean-Philippe; Fournié, Jean-Jacques; Poupot, Mary

    2016-01-01

    The availability of specific stimuli to induce the anticancer cytotoxicity of human TCRV?9-expressing T lymphocytes has allowed the development of ?? T cell-based cancer immunotherapies. However, the stringent dependence of such strategies on the inherently toxic IL-2 has raised safety concerns for patients, justifying a search for alternative methods for inducing ?? T cell stimulation. IL-33 is a ?-chain receptor-independent cytokine of the IL-1 superfamily that is expressed by endothelial cells from a tumor microenvironment and can sustain Th1 and Th2 immune responses. Therefore, we investigated its ability to support the stimulation of human TCRV?9(+) ?? T cells. In this study, we report that IL-33 efficiently sustained the in vitro activation of V?9 T lymphocytes by synthetic phosphoantigens, zoledronate, and a BTN3A1 Ab in the absence of an exogenous supply of IL-2. IL-33 was as potent as IL-2 in allowing the proliferative amplification of V?9 T cells isolated from PBMC following activation by the synthetic phosphoantigen bromohydrin pyrophosphate. IL-33 also induced an identical maturation into TNF-?- and IFN-?-producing Th1 effector memory cells, and IL-33-stimulated cells showed an equivalent cytotoxicity for various tumor cells in vitro. Finally, we found that the bioactivity of IL-33 on the V?9 T cell was indirectly mediated through contact with CD4 T cells and IL-2 production by CD4 T cells and V?9 T cells themselves. These data posit IL-33 as an alternative to IL-2 for V?9 T cell-based cancer immunotherapies. PMID:26608919

  6. Stat5 is required for IL-2-induced cell cycle progression of peripheral T cells.

    PubMed

    Moriggl, R; Topham, D J; Teglund, S; Sexl, V; McKay, C; Wang, D; Hoffmeyer, A; van Deursen, J; Sangster, M Y; Bunting, K D; Grosveld, G C; Ihle, J N

    1999-02-01

    Many cytokines activate two highly homologous Stat proteins, 5a and 5b. Mice deficient in both genes lack all growth hormone and prolactin functions but retain functions associated with cytokines such as erythropoietin. Here, we demonstrate that, while lymphoid development is normal, Stat5a/b mutant peripheral T cells are profoundly deficient in proliferation and fail to undergo cell cycle progression or to express genes controlling cell cycle progression. In addition, the mice lack NK cells, develop splenomegaly, and have T cells with an activated phenotype, phenotypes seen in IL-2 receptor beta chain-deficient mice. These phenotypes are not seen in mice lacking Stat5a or Stat5b alone. The results demonstrate that the Stat5 proteins, redundantly, are essential mediators of IL-2 signaling in T cells. PMID:10072077

  7. Mechanistic target of rapamycin complex 1 is critical for invariant natural killer T-cell development and effector function.

    PubMed

    Shin, Jinwook; Wang, Shang; Deng, Wenhai; Wu, Jinhong; Gao, Jimin; Zhong, Xiao-Ping

    2014-02-25

    The mechanisms that control invariant natural killer T (iNKT)-cell development and function are still poorly understood. The mechanistic or mammalian target of rapamycin (mTOR) integrates various environmental signals/cues to regulate cell growth, proliferation, metabolism, and survival. We report here that ablation of mTOR complex 1 (mTORC1) signaling by conditionally deleting Raptor causes severe defects in iNKT-cell development at early stages, leading to drastic reductions in iNKT-cell numbers in the thymus and periphery. In addition, loss of Raptor impairs iNKT-cell proliferation and production of cytokines upon ?-galactosylceramide stimulation in vitro and in vivo, and inhibits liver inflammation in an iNKT cell-mediated hepatitis model. Furthermore, Raptor deficiency and rapamycin treatment lead to aberrant intracellular localization and functional impairment of promyelocytic leukemia zinc-finger, a transcription factor critical for iNKT-cell development and effector programs. Our findings define an essential role of mTORC1 to direct iNKT-cell lineage development and effector function. PMID:24516149

  8. [Psychomotor development and its disorders: between normal and pathological development].

    PubMed

    Vericat, Agustina; Bibiana Orden, Alicia

    2013-10-01

    This article discusses some aspects of psychomotor development and its disorders, with special emphasis on psychomotor retardation. Diagnostic classifications of psychomotor problems, such as DSM-IV and CIE-10, are referred to and their advantages and disadvantages are analyzed. The concept of normality as a synonym for the statistical mean in the context of psychomotor disorders is also analyzed in order to consider its dynamic and variability, thereby avoiding the normality/pathology opposition, while some issues, such as the social and cultural aspects, are highlighted, making it possible to rethink the universality and relativity of psychomotor development. PMID:24061024

  9. The impact of telomere erosion on memory CD8+ T cells in patients with X-linked lymphoproliferative syndrome.

    PubMed

    Plunkett, Fiona J; Franzese, Ornella; Belaramani, Lavina L; Fletcher, Jean M; Gilmour, Kimberly C; Sharifi, Reza; Khan, Naeem; Hislop, Andrew D; Cara, Andrea; Salmon, Mike; Gaspar, H Bobby; Rustin, Malcom H A; Webster, David; Akbar, Arne N

    2005-08-01

    Patients with X-linked lymphoproliferative syndrome (XLP) experience excessive T cell proliferation after primary Epstein-Barr virus (EBV) infection, due to mutations in the signalling lymphocyte activation molecule (SLAM) associated protein (SAP) molecule. We examined the impact of dysfunctional proliferative control on the extent of CD8+ T cell differentiation in XLP patients who recovered from primary EBV infection. Although these young patients have normal numbers of lytic and latent EBV-epitope-specific CD8+ T cells, they were extremely differentiated as defined by loss of CCR7 and CD27, low telomerase activity and very short telomeres. This was not a direct effect arising from the loss of SAP, but was due to excessive T cell stimulation due to this defect. Thus, transduction of XLP CD8+ T cells with the catalytic component of telomerase (hTERT), but not SAP, prevented telomere loss and considerably extended proliferative lifespan in vitro. These results indicate that excessive proliferation in CD8+ T cells in XLP patients may lead to end-stage differentiation and loss of functional EBV-specific CD8+ T cells through replicative senescence. This may contribute to the defective immunity found in XLP patients who survive acute EBV infection who develop EBV-related B cell lymphomas before the fourth decade of life. PMID:15992610

  10. Immunoregulatory changes induced by total lymphoid irradiation. II. Development of thymus-leukemia antigen-positive and -negative suppressor T cells that differ in their regulatory function

    SciTech Connect

    King, D.P.; Strober, S.

    1981-07-01

    BALB/c mice treated with total lymphoid irradiation (TLI) develop non-antigen-specific suppressor cells of the adoptive secondary antibody response and of the mixed leukocyte reaction. Suppressors of the adoptive anti-DNP response were eliminated by incubation of spleen cells with anti-Thy-1.2 or anti-thymus-leukemia (TL) antiserum and complement before cell transfer. Thymectomy before TLI prevented the appearance of the latter suppressor cells. On the other hand, suppressors of the MLR were eliminated by incubation of spleen cells with anti-Thy-1.2 but not anti-TL antiserum and complement. Thymectomy before TLI did not prevent their subsequent development. Thus, two subpopulations of suppressor T cells that differ in the expression of the TL surface antigen, dependence on the presence of the thymus, and in regulatory functions develop after TLI. The TL+, thymus-dependent cell suppresses the adoptive antibody response, and the TL-, thymus-independent cell suppresses the MLR.

  11. Cutaneous immunosurveillance by self-renewing dermal ?? T cells

    PubMed Central

    Sumaria, Nital; Roediger, Ben; Qin, Jim; Pinto, Rachel; Cavanagh, Lois L.; Shklovskaya, Elena; Fazekas de St. Groth, Barbara; Triccas, James A.

    2011-01-01

    The presence of ?? T cell receptor (TCR)–expressing cells in the epidermis of mice, termed dendritic epidermal T cells (DETCs), is well established. Because of their strict epidermal localization, it is likely that DETCs primarily respond to epithelial stress, such as infections or the presence of transformed cells, whereas they may not participate directly in dermal immune responses. In this study, we describe a prominent population of resident dermal ?? T cells, which differ from DETCs in TCR usage, phenotype, and migratory behavior. Dermal ?? T cells are radioresistant, cycle in situ, and are partially depend on interleukin (IL)-7, but not IL-15, for their development and survival. During mycobacterial infection, dermal ?? T cells are the predominant dermal cells that produce IL-17. Absence of dermal ?? T cells is associated with decreased expansion in skin draining lymph nodes of CD4+ T cells specific for an immunodominant Mycobacterium tuberculosis epitope. Decreased CD4+ T cell expansion is related to a reduction in neutrophil recruitment to the skin and decreased BCG shuttling to draining lymph nodes. Thus, dermal ?? T cells are an important part of the resident cutaneous immunosurveillance program. Our data demonstrate functional specialization of T cells in distinct microcompartments of the skin. PMID:21339323

  12. Therapeutic Potential of Hyporesponsive CD4+ T Cells in Autoimmunity

    PubMed Central

    Maggi, Jaxaira; Schafer, Carolina; Ubilla-Olguín, Gabriela; Catalán, Diego; Schinnerling, Katina; Aguillón, Juan C.

    2015-01-01

    The interaction between dendritic cells (DCs) and T cells is crucial on immunity or tolerance induction. In an immature or semi-mature state, DCs induce tolerance through T-cell deletion, generation of regulatory T cells, and/or induction of T-cell anergy. Anergy is defined as an unresponsive state that retains T cells in an “off” mode under conditions in which immune activation is undesirable. This mechanism is crucial for the control of T-cell responses against self-antigens, thereby preventing autoimmunity. Tolerogenic DCs (tDCs), generated in vitro from peripheral blood monocytes of healthy donors or patients with autoimmune pathologies, were shown to modulate immune responses by inducing T-cell hyporesponsiveness. Animal models of autoimmune diseases confirmed the impact of T-cell anergy on disease development and progression in vivo. Thus, the induction of T-cell hyporesponsiveness by tDCs has become a promising immunotherapeutic strategy for the treatment of T-cell-mediated autoimmune disorders. Here, we review recent findings in the area and discuss the potential of anergy induction for clinical purposes. PMID:26441992

  13. The Challenges and Opportunities for Development of a T-Cell Epitope-Based Herpes Simplex Vaccine

    PubMed Central

    Kuo, Tiffany; Wang, Christine; Badakhshan, Tina; Chilukuri, Sravya; BenMohamed, Lbachir

    2014-01-01

    The infections with herpes simplex virus type 1 and type 2 (HSV-1 & HSV-2) have been prevalent since the ancient Greek times. To this day, they still affect a staggering number of over a half billion individuals worldwide. HSV-2 infections cause painful genital herpes, encephalitis, and death in newborns. HSV-1 infections are more prevalent than HSV-2 infections and cause potentially blinding ocular herpes, oro-facial herpes and encephalitis. While genital herpes in mainly caused by HSV-2 infections, in recent years, there is an increase in the proportion of genital herpes caused by HSV-1 infections in young adults, which reach 50% in some western societies. While prophylactic and therapeutic HSV vaccines remain urgently needed for centuries their development has been notoriously difficult. During the most recent National Institute of Health (NIH) workshop titled "Next Generation Herpes Simplex Virus Vaccines: The Challenges and Opportunities", basic researchers, funding agencies, and pharmaceutical representatives gathered: (i) to assess the status of herpes vaccine research; and (ii) to identify the gaps and propose alternative approaches in developing a safe and efficient herpes vaccine. One “common denominator” among previously failed clinical herpes vaccine trials is that they either used a whole virus or whole viral proteins, which contain both pathogenic “symptomatic” and protective “asymptomatic” antigens/epitopes. In this report, we continue to advocate that using an “asymptomatic” epitope-based vaccine strategy that selectively incorporates protective epitopes which: (i) are exclusively recognized, in vitro, by effector memory CD4+ and CD8+ TEM cells from “naturally” protected seropositive asymptomatic individuals; and (ii) protect, in vivo, human leukocyte antigen (HLA) transgenic animal models from ocular and genital herpes infections and diseases, could be the answer to many of the scientific challenges facing HSV vaccine development. We review the role of animal models in herpes vaccine development and discuss its current status, challenges, and prospects. PMID:25446827

  14. 778 VOLUME 13 NUMBER 8 AUGUST 2012 nature immunology Elucidating the mechanisms by which naive CD4+ T cells differentiate

    E-print Network

    expression is required for the development of T cells in the thymus. In peripheral CD4+ T cells, interleukin,29. Lymphocytes have high expression of Sox4, and Sox4 regu- lates T cell differentiation in the thymus

  15. The fragile environments of inexpensive CD4+ T-cell enumeration in the least developed countries: strategies for accessible support.

    PubMed

    Larsen, Christoph H

    2008-01-01

    With the advent of affordable antiretroviral treatment (ART), flow cytometry has ventured out of the exclusive realms of First World research to the resource-strapped clinical environment of developing countries (DCs). Flow cytometric instrumentation for ART has become more cost-efficient, thanks to simplified, yet accurate protocols and smart technologies. These positive developments have, however, not taken shape without problems, as health care in DCs remains weak due to chronic underfunding of their primary health systems. In addition, the multiplicity of donors has created parallel infrastructures that are difficult to manage and may undermine the responsibilities of public services. Hence, there is a prevailing lack of attention to maintenance, support, and human resource development. Not uncommonly, the procurement of high-value equipment is guided by nontechnical interests with mixed results. As conventional service contracts are unpopular, the sustainability of equipment is under serious threat after warranty periods, with environmental factors such as dust and unreliable power supplies being well-known culprits. Reagent supplies and servicing constitute further challenges, where a combination of short reagent shelf life, cold-box shipping, huge distances across poor infrastructures, rigid accounting procedures, and erratic customs requirements cause significant delays and extra costs. Although excellent, highly trained or trainable local staff is available, it is frequently diverted by brain drain from the government sector to privately funded hospitals, research facilities, and overseas postings. Despite these challenges, corporate service management has commonly remained loyal to its roots in the developed world.A number of propositions address the current situation: "Reagent-rental" agreements represent an attractive alternative to service contracts, while smart instrument design has started to make inroads into more robust device concepts. To avoid logistical bottlenecks, reagents call for lyophilization and increased heat stability. Newly designed remote diagnostic tools are expected to save costs on service visits. Furthermore, web-based customer-relationship management and enterprise resource planning software is expected to ease the existing complex communication- and logistics issues. In addition, a public-private partnership is proposed that involves government, manufacturers, and local distributors with field application specialists. The latter operate crossbrand as independent subcontractors to manufacturers under a nationally endorsed cost-capping and quality assurance agreement to service all cytometric devices common in the region. These locally run networks may serve as "templates" for improved laboratory services in general, in collaboration with CD4 counting, haematology and infectious disease diagnostics. PMID:18228565

  16. Regulatory T Cells as Immunotherapy

    PubMed Central

    Singer, Benjamin D.; King, Landon S.; D’Alessio, Franco R.

    2014-01-01

    Regulatory T cells (Tregs) suppress exuberant immune system activation and promote immunologic tolerance. Because Tregs modulate both innate and adaptive immunity, the biomedical community has developed an intense interest in using Tregs for immunotherapy. Conditions that require clinical tolerance to improve outcomes – autoimmune disease, solid organ transplantation, and hematopoietic stem cell transplantation – may benefit from Treg immunotherapy. Investigators have designed ex vivo strategies to isolate, preserve, expand, and infuse Tregs. Protocols to manipulate Treg populations in vivo have also been considered. Barriers to clinically feasible Treg immunotherapy include Treg stability, off-cell effects, and demonstration of cell preparation purity and potency. Clinical trials involving Treg adoptive transfer to treat graft versus host disease preliminarily demonstrated the safety and efficacy of Treg immunotherapy in humans. Future work will need to confirm the safety of Treg immunotherapy and establish the efficacy of specific Treg subsets for the treatment of immune-mediated disease. PMID:24575095

  17. Genetic engineering with T cell receptors?

    PubMed Central

    Zhang, Ling; Morgan, Richard A.

    2011-01-01

    In the past two decades, human gene transfer research has been translated from a laboratory technology to clinical evaluation. The success of adoptive transfer of tumor-reactive lymphocytes to treat the patients with metastatic melanoma has led to new strategies to redirect normal T cells to recognize tumor antigens by genetic engineering with tumor antigen-specific T cell receptor (TCR) genes. This new strategy can generate large numbers of defined antigen-specific cells for therapeutic application. Much progress has been made to TCR gene transfer systems by optimizing gene expression and gene transfer protocols. Vector and protein modifications have enabled excellent expression of introduced TCR chains in human lymphocytes with reduced mis-pairing between the introduced and endogenous TCR chains. Initial clinical studies have demonstrated that TCR gene-engineered T cells could mediate tumor regression in vivo. In this review, we discuss the progress and prospects of TCR gene-engineered T cells as a therapeutic strategy for treating patients with melanoma and other cancers. PMID:22178904

  18. T cell-specific inhibition of multiple apoptotic pathways blocks negative selection and causes autoimmunity.

    PubMed

    Burger, Megan L; Leung, Kenneth K; Bennett, Margaux J; Winoto, Astar

    2014-01-01

    T cell self-tolerance is thought to involve peripheral tolerance and negative selection, involving apoptosis of autoreactive thymocytes. However, evidence supporting an essential role for negative selection is limited. Loss of Bim, a Bcl-2 BH3-only protein essential for thymocyte apoptosis, rarely results in autoimmunity on the C57BL/6 background. Mice with T cell-specific over-expression of Bcl-2, that blocks multiple BH3-only proteins, are also largely normal. The nuclear receptor Nur77, also implicated in negative selection, might function redundantly to promote apoptosis by associating with Bcl-2 and exposing its potentially pro-apoptotic BH3 domain. Here, we report that T cell-specific expression of a Bcl2 BH3 mutant transgene results in enhanced rescue of thymocytes from negative selection. Concomitantly, Treg development is increased. However, aged BH3 mutant mice progressively accumulate activated, autoreactive T cells, culminating in development of multi-organ autoimmunity and lethality. These data provide strong evidence that negative selection is crucial for establishing T cell tolerance. PMID:25182415

  19. Retargeting Oncolytic Vesicular Stomatitis Virus to Human T-Cell Lymphotropic Virus Type 1-Associated Adult T-Cell Leukemia

    PubMed Central

    Betancourt, Dillon; Ramos, Juan Carlos

    2015-01-01

    ABSTRACT Adult T cell leukemia/lymphoma (ATL) is an aggressive cancer of CD4/CD25+ T lymphocytes, the etiological agent of which is human T-cell lymphotropic virus type 1 (HTLV-1). ATL is highly refractory to current therapies, making the development of new treatments a high priority. Oncolytic viruses such as vesicular stomatitis virus (VSV) are being considered as anticancer agents since they readily infect transformed cells compared to normal cells, the former appearing to exhibit defective innate immune responses. Here, we have evaluated the efficacy and safety of a recombinant VSV that has been retargeted to specifically infect and replicate in transformed CD4+ cells. This was achieved by replacing the single VSV glycoprotein (G) with human immunodeficiency virus type 1 (HIV-1) gp160 to create a hybrid fusion protein, gp160G. The resultant virus, VSV-gp160G, was found to only target cells expressing CD4 and retained robust oncolytic activity against HTLV-1 actuated ATL cells. VSV-gp160G was further noted to be highly attenuated and did not replicate efficiently in or induce significant cell death of primary CD4+ T cells. Accordingly, VSV-gp160G did not elicit any evidence of neurotoxicity even in severely immunocompromised animals such as NOD/Shi-scid, IL-2R?-c-null (NSG) mice. Importantly, VSV-gp160G effectively exerted potent oncolytic activity in patient-derived ATL transplanted into NSG mice and facilitated a significant survival benefit. Our data indicate that VSV-gp160G exerts potent oncolytic efficacy against CD4+ malignant cells and either alone or in conjunction with established therapies may provide an effective treatment in patients displaying ATL. IMPORTANCE Adult T cell leukemia (ATL) is a serious form of cancer with a high mortality rate. HTLV-1 infection is the etiological agent of ATL and, unfortunately, most patients succumb to the disease within a few years. Current treatment options have failed to significantly improve survival rate. In this study, we developed a recombinant strain of vesicular stomatitis virus (VSV) that specifically targets transformed CD4+ T cells through replacement of the G protein of VSV with a hybrid fusion protein, combining domains from gp160 of HIV-1 and VSV-G. This modification eliminated the normally broad tropism of VSV and restricted infection to primarily the transformed CD4+ cell population. This effect greatly reduced neurotoxic risk associated with VSV infection while still allowing VSV to effectively target ATL cells. PMID:26378177

  20. Development of ultra-super sensitive immunohistochemistry and its application to the etiological study of adult T-cell leukemia/lymphoma.

    PubMed

    Hasui, Kazuhisa; Wang, Jia; Tanaka, Yuetsu; Izumo, Shuji; Eizuru, Yoshito; Matsuyama, Takami

    2012-04-26

    Antigen retrieval (AR) and ultra-super sensitive immunohistochemistry (ultra-IHC) have been established for application to archival human pathology specimens. The original ultra-IHC was the ImmunoMax method or the catalyzed signal amplification system (ImmunoMax/CSA method), comprising the streptavidin-biotin complex (sABC) method and catalyzed reporter deposition (CARD) reaction with visualization of its deposition. By introducing procedures to diminish non-specific staining in the original ultra-IHC method, we developed the modified ImmunoMax/CSA method with AR heating sections in an AR solution (heating-AR). The heating-AR and modified ImmunoMax/CSA method visualized expression of the predominantly simple present form of HTLV-1 proviral DNA pX region p40Tax protein (Tax) in adult T-cell leukemia/lymphoma (ATLL) cells in archival pathology specimens in approximately 75% of cases. The simple present form of Tax detected exhibited a close relation with ATLL cell proliferation. We also established a new simplified CSA (nsCSA) system by replacing the sABC method with the secondary antibody- and horse radish peroxidase-labeled polymer reagent method, introducing the pretreatments blocking non-specific binding of secondary antibody reagent, and diminishing the diffusion of deposition in the CARD reaction. Combined with AR treating sections with proteinase K solution (enzymatic-AR), the nsCSA system visualized granular immunostaining of the complex present form of Tax in a small number of ATLL cells in most cases, presenting the possibility of etiological pathological diagnosis of ATLL and suggesting that the complex present form of Tax-positive ATLL cells were young cells derived from ATLL stem cells. The heating-AR and ultra-IHC detected physiological expression of the p53 protein and its probable phosphorylation by Tax in peripheral blood mononuclear cells of peripheral blood tissue specimens from HTLV-1 carriers, as well as physiological and pathological expression of the molecules involved with G1 phase progression and G1-S phase transition (E2F-1, E2F-4, DP-1, and cyclin E) in ATLL and peripheral T-cell lymphoma cells. The ultra-IHC with AR is useful for etiological pathological diagnosis of ATLL since HTLV-1 pathogenicity depends on that of Tax, and can be a useful tool for studies translating advanced molecular biology and pathology to human pathology. PMID:22685351

  1. Sleep-dependent activity of T cells and regulatory T cells.

    PubMed

    Bollinger, T; Bollinger, A; Skrum, L; Dimitrov, S; Lange, T; Solbach, W

    2009-02-01

    A number of immunological functions are dependent on circadian rhythms and regular sleep. This has impact on the type and magnitude of immune responses following antigenic challenge, for example in vaccination. Little is known about the underlying mechanisms. One possibility may be the circadian and sleep-dependent modulation of CD4(+)CD25(-) T cell responses by CD4(+)CD25(+) natural regulatory T cells (nT(reg)). In a variety of studies, nT(reg) have been shown to regulate T cell responses negatively. Thus, we investigated the influence of sleep and circadian rhythm on the number and function of nT(reg) as well as on the function of CD4(+)CD25(-) T cells. Seven healthy young men were examined under defined conditions on two occasions, i.e. during sleep and sleep deprivation. Venous blood was drawn periodically; numbers of nT(reg), suppressive activity of nT(reg), interleukin-2 production and proliferation of CD4(+)CD25(-) T cells were explored in vitro. nT(reg) counts revealed a significant circadian rhythm with highest levels during the night (mean 95 nT(reg)/microl) and lowest levels during the day (mean 55 nT(reg)/microl). During normal sleep, the suppressive activity of nT(reg) was highest at 02.00 h and somewhat lower at 15.00 h. Surprisingly, almost no suppressive activity was present at 07.00 h. Deprivation of sleep abrogated this rhythm. CD4(+)CD25(-) T cell proliferation was dampened significantly by sleep deprivation. This is the first study in human cells to show that nT(reg) number and function follow a rhythm across the 24-h period. Furthermore, sleep deprivation severely disturbs the functional rhythm of nT(reg) and CD4(+)CD25(-) T cells. PMID:19040608

  2. Intestinal ?? T-cell lymphomas are most frequently of type II enteropathy-associated T-cell type.

    PubMed

    Wilson, Amanda L; Swerdlow, Steven H; Przybylski, Grzegorz K; Surti, Urvashi; Choi, John K; Campo, Elias; Trucco, Massimo M; Van Oss, S Branden; Felgar, Raymond E

    2013-06-01

    Enteropathy-associated T-cell lymphoma includes type I cases and distinctive type II cases that, according to 2008 and 2010 World Health Organization descriptions, are T-cell receptor ?+. Although T-cell receptor ?? enteropathy-associated T-cell lymphomas are reported, it is unknown if they have distinctive features and if they should be categorized as enteropathy-associated T-cell lymphoma or as a mucocutaneous ?? T-cell lymphoma. To address these questions, the clinicopathologic, immunophenotypic, molecular, and cytogenetic features of 5 ??-enteropathy-associated T-cell lymphomas were investigated. Only 1 patient had celiac disease and had type I enteropathy-associated T-cell lymphoma, and the others fulfilled the histopathologic criteria for type II enteropathy-associated T-cell lymphoma. All lacked cutaneous involvement. A celiac disease-associated HLA type was found in the patient with CD and one of four others. All were T-cell receptor ?+, T-cell receptor ?+, ?F1-, CD3+, CD7+, CD5-, CD4-, and TIA-1+ with variable staining for CD2 (3/5), CD8 (2/5), Granzyme B (1/5), and CD56 (4/5). Fluorescence in situ hybridization demonstrated 9q34 gains in 4 cases, with 9q33-34 gains by single nucleotide polymorphism in 3 of these. Single nucleotide polymorphism analysis also demonstrated gains in 5q34-q35.1/5q35.1 (4/5), 8q24 (3/5), and in 32 other regions in 3 of 5 cases. V?1 rearrangements were identified in 4 of 4 cases with documented clonality showing the same clone in normal-appearing distant mucosa (3/3 tested cases). Thus, ??-enteropathy-associated T-cell lymphomas share many features with other enteropathy-associated T-cell lymphoma and are mostly of type II. Their usual nonactivated cytotoxic phenotype and V?1 usage are features unlike many other mucocutaneous ?? T-cell lymphomas but shared with hepatosplenic T-cell lymphoma. These findings support the conclusion that a ?? T-cell origin at extracutaneous sites does not define a specific entity. PMID:23332928

  3. Intestinal ?? T-cell lymphomas are most frequently of type II enteropathy-associated T-cell type

    PubMed Central

    Wilson, Amanda L.; Swerdlow, Steven H.; Przybylski, Grzegorz K.; Surti, Urvashi; Choi, John K.; Campo, Elias; Trucco, Massimo M.; Van Oss, S. Branden; Felgar, Raymond E.

    2013-01-01

    Summary Enteropathy-associated T-cell lymphoma includes type I cases and distinctive type II cases that, according to 2008 and 2010 World Health Organization descriptions, are T-cell receptor ?+. Although T-cell receptor ?? enteropathy-associated T-cell lymphomas are reported, it is unknown if they have distinctive features and if they should be categorized as enteropathy-associated T-cell lymphoma or as a mucocutaneous ?? T-cell lymphoma. To address these questions, the clinicopathologic, immunophenotypic, molecular, and cytogenetic features of 5 ??-enteropathy-associated T-cell lymphomas were investigated. Only 1 patient had celiac disease and had type I enteropathy-associated T-cell lymphoma, and the others fulfilled the histopathologic criteria for type II enteropathy-associated T-cell lymphoma. All lacked cutaneous involvement. A celiac disease–associated HLA type was found in the patient with CD and one of four others. All were T-cell receptor ?+, T-cell receptor ?+, ?F1?, CD3+, CD7+, CD5?, CD4?, and TIA-1+ with variable staining for CD2 (3/5), CD8 (2/5), Granzyme B (1/5), and CD56 (4/5). Fluorescence in situ hybridization demonstrated 9q34 gains in 4 cases, with 9q33-34 gains by single nucleotide polymorphism in 3 of these. Single nucleotide polymorphism analysis also demonstrated gains in 5q34-q35.1/5q35.1 (4/5), 8q24 (3/5), and in 32 other regions in 3 of 5 cases. V?1 rearrangements were identified in 4 of 4 cases with documented clonality showing the same clone in normal-appearing distant mucosa (3/3 tested cases). Thus, ??-enteropathy-associated T-cell lymphomas share many features with other enteropathy-associated T-cell lymphoma and are mostly of type II. Their usual nonactivated cytotoxic phenotype and V?1 usage are features unlike many other mucocutaneous ?? T-cell lymphomas but shared with hepatosplenic T-cell lymphoma. These findings support the conclusion that a ?? T-cell origin at extracutaneous sites does not define a specific entity. PMID:23332928

  4. Development of a hypersensitive periodate-cleavable amino acid that is methionine- and disulfide-compatible and its application in MHC exchange reagents for T cell characterisation.

    PubMed

    Amore, Alessia; Wals, Kim; Koekoek, Evelyn; Hoppes, Rieuwert; Toebes, Mireille; Schumacher, Ton N M; Rodenko, Boris; Ovaa, Huib

    2013-01-01

    Incorporation of cleavable linkers into peptides and proteins is of particular value in the study of biological processes. Here we describe the synthesis of a cleavable linker that is hypersensitive to oxidative cleavage as the result of the periodate reactivity of a vicinal amino alcohol moiety. Two strategies directed towards the synthesis of a building block suitable for solid-phase peptide synthesis were developed: a chemoenzymatic route, involving L-threonine aldolase, and an enantioselective chemical route; these led to ?,?-diamino-?-hydroxybutanoic acids in diastereoisomerically mixed and enantiopure forms, respectively. Incorporation of the 1,2-amino alcohol linker into the backbone of a peptide generated a conditional peptide that was rapidly cleaved at very low concentrations of sodium periodate. This cleavable peptide ligand was applied in the generation of MHC exchange reagents for the detection of antigen-specific T cells in peripheral blood cells. The extremely low concentration of periodate required to trigger MHC peptide exchange allowed the co-oxidation of methionine and disulfide residues to be avoided. Conditional MHC reagents hypersensitive to periodate can now be applied without limitations when UV irradiation is undesired or less practical. PMID:23280887

  5. Development of a Hypersensitive Periodate-Cleavable Amino Acid that is Methionine- and Disulfide-Compatible and its Application in MHC Exchange Reagents for T Cell Characterisation

    PubMed Central

    Amore, Alessia; Wals, Kim; Koekoek, Evelyn; Hoppes, Rieuwert; Toebes, Mireille; Schumacher, Ton N M; Rodenko, Boris; Ovaa, Huib

    2013-01-01

    Incorporation of cleavable linkers into peptides and proteins is of particular value in the study of biological processes. Here we describe the synthesis of a cleavable linker that is hypersensitive to oxidative cleavage as the result of the periodate reactivity of a vicinal amino alcohol moiety. Two strategies directed towards the synthesis of a building block suitable for solid-phase peptide synthesis were developed: a chemoenzymatic route, involving l-threonine aldolase, and an enantioselective chemical route; these led to ?,?-diamino-?-hydroxybutanoic acids in diastereoisomerically mixed and enantiopure forms, respectively. Incorporation of the 1,2-amino alcohol linker into the backbone of a peptide generated a conditional peptide that was rapidly cleaved at very low concentrations of sodium periodate. This cleavable peptide ligand was applied in the generation of MHC exchange reagents for the detection of antigen-specific T cells in peripheral blood cells. The extremely low concentration of periodate required to trigger MHC peptide exchange allowed the co-oxidation of methionine and disulfide residues to be avoided. Conditional MHC reagents hypersensitive to periodate can now be applied without limitations when UV irradiation is undesired or less practical. PMID:23280887

  6. New Strategies in Engineering T-cell Receptor Gene-Modified T cells to More Effectively Target Malignancies.

    PubMed

    Schmitt, Thomas M; Stromnes, Ingunn M; Chapuis, Aude G; Greenberg, Philip D

    2015-12-01

    The immune system, T cells in particular, have the ability to target and destroy malignant cells. However, antitumor immune responses induced from the endogenous T-cell repertoire are often insufficient for the eradication of established tumors, as illustrated by the failure of cancer vaccination strategies or checkpoint blockade for most tumors. Genetic modification of T cells to express a defined T-cell receptor (TCR) can provide the means to rapidly generate large numbers of tumor-reactive T cells capable of targeting tumor cells in vivo. However, cell-intrinsic factors as well as immunosuppressive factors in the tumor microenvironment can limit the function of such gene-modified T cells. New strategies currently being developed are refining and enhancing this approach, resulting in cellular therapies that more effectively target tumors and that are less susceptible to tumor immune evasion. Clin Cancer Res; 21(23); 5191-7. ©2015 AACR. PMID:26463711

  7. Tissue-resident memory T cells

    PubMed Central

    Shin, Haina; Iwasaki, Akiko

    2013-01-01

    Summary Tissues such as the genital tract, skin, and lung act as barriers against invading pathogens. To protect the host, incoming microbes must be quickly and efficiently controlled by the immune system at the portal of entry. Memory is a hallmark of the adaptive immune system, which confers long-term protection and is the basis for efficacious vaccines. While the majority of existing vaccines rely on circulating antibody for protection, struggles to develop antibody-based vaccines against infections such as herpes simplex virus (HSV) and human immunodeficiency virus (HIV) have underscored the need to generate memory T cells for robust antiviral control. The circulating memory T-cell population is generally divided into two subsets: effector memory (TEM) and central memory (TCM). These two subsets can be distinguished by their localization, as TCM home to secondary lymphoid organs and TEM circulate through non-lymphoid tissues. More recently, studies have identified a third subset, called tissue-resident memory (TRM) cells, based on its migratory properties. This subset is found in peripheral tissues that require expression of specific chemoattractants and homing receptors for T-cell recruitment and retention, including barrier sites such as the skin and genital tract. In this review, we categorize different tissues in the body based on patterns of memory T-cell migration and tissue residency. This review also describes the rules for TRM generation and the properties that distinguish them from circulating TEM and TCM cells. Finally, based on the failure of recent T-cell-based vaccines to provide optimal protection, we also discuss the potential role of TRM cells in vaccine design against microbes that invade through the peripheral tissues and highlight new vaccination strategies that take advantage of this newly described memory T-cell subset. PMID:23947354

  8. Effective gene suppression using small interfering RNA in hard-to-transfect human T cells.

    PubMed

    Yin, Jiyi; Ma, Zhengyu; Selliah, Nithianandan; Shivers, Debra K; Cron, Randy Q; Finkel, Terri H

    2006-05-30

    RNA interference (RNAi) is an evolutionarily conserved cellular defense mechanism that protects cells from hostile genes and regulates the function of normal genes during growth and development. In this study, we established proof of principle of small interfering RNA (siRNA) silencing in hard-to-transfect human T cell lines and primary human CD4 T cells. We used public and in-house programs to design four siRNAs each for GFP, for our novel cellular gene HALP, and for their corresponding scrambled siRNA controls. We generated siRNA expression cassettes (SECs) by PCR and directly transfected the PCR products into T cells using amaxa Nucleofector technology. The most effective SECs were selected and cloned into a TA cloning vector and titered with their respective controls to increase transfection efficiency. Flow cytometry and fluorescence microscopy analyses were performed for GFP siRNAs, and Northern blot analysis was done to assess the HALP silencing effect. These experiments demonstrate that SECs are an excellent screening tool to identify siRNA sequences effective in silencing expression of genes of interest. The vector expressing the most effective siRNA robustly inhibited GFP expression (up to 92%) in the context of co-transfection in human T cell lines and primary CD4 T cells. The optimized siRNA for our endogenous cellular gene HALP also silenced its target RNA expression by more than 90%. These studies demonstrate that the combination of SEC, siRNA expression vectors and Nucleofector technology can be successfully applied to hard-to-transfect human T cell lines and primary T cells to effectively silence genes. PMID:16603179

  9. NY-ESO-1 antigen-reactive T cell receptors exhibit diverse therapeutic capability.

    PubMed

    Sommermeyer, Daniel; Conrad, Heinke; Krönig, Holger; Gelfort, Haike; Bernhard, Helga; Uckert, Wolfgang

    2013-03-15

    The cancer-testis antigen NY-ESO-1 has been used as a target for different immunotherapies like vaccinations and adoptive transfer of antigen-specific cytotoxic T cells, as it is expressed in various tumor types and has limited expression in normal cells. The in vitro generation of T cells with defined antigen specificity by T cell receptor (TCR) gene transfer is an established method to create cells for immunotherapy. However, an extensive characterization of TCR which are candidates for treatment of patients is crucial for successful therapies. The TCR has to be efficiently expressed, their affinity to the desired antigen should be high enough to recognize low amounts of endogenously processed peptides on tumor cells, and the TCR should not be cross-reactive to other antigens. We characterized three NY-ESO-1 antigen-reactive cytotoxic T lymphocyte clones which were generated by different approaches of T cell priming (autologous, allogeneic), and transferred their TCR into donor T cells for more extensive evaluations. Although one TCR most efficiently bound MHC-multimers loaded with NY-ESO-1 peptide, T cells expressing this transgenic TCR were not able to recognize endogenously processed antigen. A second TCR recognized HLA-A2 independent of the bound peptide beside its much stronger recognition of NY-ESO-1 bound to HLA-A2. A third TCR displayed an intermediate but peptide-specific performance in all functional assays and, therefore, is the most promising candidate TCR for further clinical development. Our data indicate that multiple parameters of TCR gene-modified T cells have to be evaluated to identify an optimal TCR candidate for adoptive therapy. PMID:22907642

  10. SYK expression endows human ZAP70-deficient CD8 T cells with residual TCR signaling.

    PubMed

    Hauck, Fabian; Blumenthal, Britta; Fuchs, Sebastian; Lenoir, Christelle; Martin, Emmanuel; Speckmann, Carsten; Vraetz, Thomas; Mannhardt-Laakmann, Wilma; Lambert, Nathalie; Gil, Marine; Borte, Stephan; Audrain, Marie; Schwarz, Klaus; Lim, Annick; Schamel, Wolfgang W; Fischer, Alain; Ehl, Stephan; Rensing-Ehl, Anne; Picard, Capucine; Latour, Sylvain

    2015-12-01

    Autosomal recessive human ZAP70 deficiency is a rare cause of combined immunodeficiency (CID) characterized by defective CD4 T cells and profound CD8 T cell lymphopenia. Herein, we report two novel patients that extend the molecular genetics, the clinical and functional phenotypes associated with the ZAP70 deficiency. The patients presented as infant-onset CID with severe infections caused by varicella zoster virus and live vaccines. Retrospective TCR excision circle newborn screening was normal in both patients. One patient carried a novel non-sense mutation (p.A495fsX75); the other a previously described misense mutation (p.A507V). In contrast to CD4 T cells, the majority of the few CD8 T cells showed expression of the ZAP70-related tyrosine kinase SYK that correlated with residual TCR signaling including calcium flux and degranulation. Our findings highlight the differential requirements of ZAP70 and SYK during thymic development, peripheral homeostasis as well as effector functions of CD4 and CD8 T cells. PMID:26187144

  11. Ageing combines CD4 T cell lymphopenia in secondary lymphoid organs and T cell accumulation in gut associated lymphoid tissue

    PubMed Central

    2014-01-01

    Background CD4 T cell lymphopenia is an important T cell defect associated to ageing. Higher susceptibility to infections, cancer, or autoimmune pathologies described in aged individuals is thought to partly rely on T cell lymphopenia. We hypothesize that such diverse effects may reflect anatomical heterogeneity of age related T cell lymphopenia. Indeed, no data are currently available on the impact of ageing on T cell pool recovered from gut associated lymphoid tissue (GALT), a crucial site of CD4 T cell accumulation. Results Primary, secondary and tertiary lymphoid organs of C57BL/6 animals were analysed at three intervals of ages: 2 to 6 months (young), 10 to 14 months (middle-aged) and 22 to 26 months (old). We confirmed that ageing preferentially impacted CD4 T cell compartment in secondary lymphoid organs. Importantly, a different picture emerged from gut associated mucosal sites: during ageing, CD4 T cell accumulation was progressively developing in colon and small intestine lamina propria and Peyer’s patches. Similar trend was also observed in middle-aged SJL/B6 F1 mice. Interestingly, an inverse correlation was detected between CD4 T cell numbers in secondary lymphoid organs and colonic lamina propria of C57BL/6 mice whereas no increase in proliferation rate of GALT CD4 T cells was detected. In contrast to GALT, no CD4 T cell accumulation was detected in lungs and liver in middle-aged animals. Finally, the concomitant accumulation of CD4 T cell in GALT and depletion in secondary lymphoid organs during ageing was detected both in male and female animals. Conclusions Our data thus demonstrate that T cell lymphopenia in secondary lymphoid organs currently associated to ageing is not sustained in gut or lung mucosa associated lymphoid tissues or non-lymphoid sites such as the liver. The inverse correlation between CD4 T cell numbers in secondary lymphoid organs and colonic lamina propria and the absence of overt proliferation in GALT suggest that marked CD4 T cell decay in secondary lymphoid organs during ageing reflect redistribution of CD4 T cells rather than generalized CD4 T cell decay. Such anatomical heterogeneity may provide an important rationale for the diversity of immune defects observed during ageing. PMID:24829607

  12. The CD4+ T-cell response to protein immunization is independent of accompanying IFN-gamma-producing CD8+ T cells.

    PubMed Central

    Doyle, A G; Ramm, L; Kelso, A

    1998-01-01

    By virtue of their strong bias towards production of interferon-gamma (IFN-gamma), CD8+ T cells have the potential to promote the development of type 1 immune responses. We have previously shown that the CD4+ T-cell response to immunization with the protein antigen keyhole limpet haemocyanin (KLH) has a mixed interleukin-4 (IL-4)/IFN-gamma production profile. Here we show that this immunization regimen also stimulates accumulation in the draining lymph nodes of CD8+ T cells, which preferentially contain IFN-gamma mRNA ex vivo and secrete IFN-gamma protein in vitro. This provides a model to test whether CD8+ cell-derived IFN-gamma participates in the normal control of the immune response to a non-viable exogenous antigen. To investigate regulation of the anti-KLH response by the CD8+ population or IFN-gamma produced by this or other cell types, mice were administered depleting antibodies. Depletion of CD8+ cells had no effect on the frequency of clonogenic KLH-specific CD4+ T cells, the IL-4/IFN-gamma profiles of their progeny, or the isotype profiles of the serum antibody response to KLH. In contrast, IFN-gamma neutralization diminished cell accumulation in the lymph nodes and reduced both the frequency of KLH-specific CD4+ T cells that gave rise to IFN-gamma-producing clones and serum titres of KLH-specific IgG2a and IgG3. Therefore, despite the potential for cross-regulation, the CD4+ T-cell response to this immunogen is independent of the IFN-gamma-skewed CD8+ response. Images Figure 2 PMID:9640244

  13. The production of alpha/beta and gamma/delta double negative (DN) T-cells and their role in the maintenance of pregnancy.

    PubMed

    Chapman, John C; Chapman, Fae M; Michael, Sandra D

    2015-01-01

    The ability of the thymus gland to convert bone marrow-derived progenitor cells into single positive (SP) T-cells is well known. In this review we present evidence that the thymus, in addition to producing SP T-cells, also has a pathway for the production of double negative (DN) T-cells. The existence of this pathway was noted during our examination of relevant literature to determine the cause of sex steroid-induced thymocyte loss. In conducting this search our objective was to answer the question of whether thymocyte loss is the end product of a typical interaction between the reproductive and immune systems, or evidence that the two systems are incompatible. We can now report that "thymocyte loss" is a normal process that occurs during the production of DN T-cells. The DN T-cell pathway is unique in that it is mediated by thymic mast cells, and becomes functional following puberty. Sex steroids initiate the development of the pathway by binding to an estrogen receptor alpha located in the outer membrane of the mast cells, causing their activation. This results in their uptake of extracellular calcium, and the production and subsequent release of histamine and serotonin. Lymphatic vessels, located in the subcapsular region of the thymus, respond to the two vasodilators by undergoing a substantial and preferential uptake of gamma/delta and alpha/beta DN T- cells. These T- cells exit the thymus via efferent lymphatic vessels and enter the lymphatic system.The DN pathway is responsible for the production of three subsets of gamma/delta DN T-cells and one subset of alpha/beta DN T-cells. In postpubertal animals approximately 35 % of total thymocytes exit the thymus as DN T-cells, regardless of sex. In pregnant females, their levels undergo a dramatic increase. Gamma/delta DN T-cells produce cytokines that are essential for the maintenance of pregnancy. PMID:26164866

  14. MicroRNA-128-3p is a novel oncomiR targeting PHF6 in T-cell acute lymphoblastic leukemia

    PubMed Central

    Mets, Evelien; Van Peer, Gert; Van der Meulen, Joni; Boice, Michael; Taghon, Tom; Goossens, Steven; Mestdagh, Pieter; Benoit, Yves; De Moerloose, Barbara; Van Roy, Nadine; Poppe, Bruce; Vandesompele, Jo; Wendel, Hans-Guido; Van Vlierberghe, Pieter; Speleman, Frank; Rondou, Pieter

    2014-01-01

    T-cell acute lymphoblastic leukemia arises from the leukemic transformation of developing thymocytes and results from cooperative genetic lesions. Inactivation of the PHF6 gene is frequently observed in T-cell acute lymphoblastic leukemia, suggesting an important tumor suppressive role for PHF6 in the pathobiology of this leukemia. Although the precise function of PHF6 is still unknown, this gene is most likely involved in chromatin regulation, a strongly emerging theme in T-cell acute lymphoblastic leukemia. In this context, our previous description of a cooperative microRNA regulatory network controlling several well-known T-cell acute lymphoblastic leukemia tumor suppressor genes, including PHF6, is of great importance. Given the high frequency of PHF6 lesions in T-cell acute lymphoblastic leukemia and the integration of PHF6 in this microRNA regulatory network, we aimed to identify novel oncogenic microRNAs in T-cell acute lymphoblastic leukemia which suppress PHF6. To this end, we performed an unbiased PHF6 3?UTR-microRNA library screen and combined the results with microRNA profiling data of samples from patients with T-cell acute lymphoblastic leukemia and normal thymocyte subsets. We selected miR-128-3p as a candidate PHF6-targeting, oncogenic microRNA and demonstrated regulation of PHF6 expression upon modulation of this microRNA in T-cell acute lymphoblastic leukemia cell lines. In vivo evidence of an oncogenic role of this microRNA in T-cell acute lymphoblastic leukemia was obtained through accelerated leukemia onset in a NOTCH1-induced T-cell acute lymphoblastic leukemia mouse model upon miR-128-3p over-expression. We conclude that miR-128-3p is a strong novel candidate oncogenic microRNA in T-cell acute lymphoblastic leukemia which targets the PHF6 tumor suppressor gene. PMID:24895337

  15. Stable nonviral gene transfer into primary human T cells.

    PubMed

    Magg, T; Hartrampf, S; Albert, M H

    2009-09-01

    Effective techniques for the stable genetic modification of peripheral T cells would facilitate functional gene studies and the development of gene therapeutic approaches. However, many approaches to genetically modify T cells are hampered by low transfection efficiency, direct cell toxicity, and the need for specialized laboratory space. In this study we investigated the Amaxa Nucleofector platform, a nonviral technique to transfect primary human T cells. A plasmid equipped with two different promoters enabled concomitant expression of a gene of interest and of a cell surface marker allowing for immunomagnetic cell enrichment. This resulted in highly purified populations of gene-modified T cells and, after repeated enrichment steps, provided stably and homogeneously transfected, fully functional human T cells. In summary, this study provides proof of principle that human T cells can be altered to homogeneously and stably express a gene of interest by a nonviral technique. This should enable further studies on T cell physiology and ultimately facilitate the translation of treatment approaches either for diseases that are caused by defective gene function in T cells or for diseases that require genetically designed T cell therapy. PMID:19485761

  16. CD1 and mycobacterial lipids activate human T cells.

    PubMed

    Van Rhijn, Ildiko; Moody, D Branch

    2015-03-01

    For decades, proteins were thought to be the sole or at least the dominant source of antigens for T cells. Studies in the 1990s demonstrated that CD1 proteins and mycobacterial lipids form specific targets of human ?? T cells. The molecular basis by which T-cell receptors (TCRs) recognize CD1-lipid complexes is now well understood. Many types of mycobacterial lipids function as antigens in the CD1 system, and new studies done with CD1 tetramers identify T-cell populations in the blood of tuberculosis patients. In human populations, a fundamental difference between the CD1 and major histocompatibility complex systems is that all humans express nearly identical CD1 proteins. Correspondingly, human CD1 responsive T cells show evidence of conserved TCRs. In addition to natural killer T cells and mucosal-associated invariant T (MAIT cells), conserved TCRs define other subsets of human T cells, including germline-encoded mycolyl-reactive (GEM) T cells. The simple immunogenetics of the CD1 system and new investigative tools to measure T-cell responses in humans now creates a situation in which known lipid antigens can be developed as immunodiagnostic and immunotherapeutic reagents for tuberculosis disease. PMID:25703557

  17. Human Papillomavirus Genome-Wide Identification of T-Cell Epitopes for Peptide Vaccine Development Against Cervical Cancer: An Integration of Computational Analysis and Experimental Assay.

    PubMed

    Li, Bo; Zheng, Xianfang; Hu, Chuancui; Cao, Yunxia

    2015-10-01

    Human papillomavirus (HPV) has long been documented as the primary factor causing cervical cancer and other complications, and development of immunotherapeutic vaccines against HPV is thought to be an important approach in preventing women from HPV infections. It is known that the first step in vaccine development is to find potent T-cell epitopes in HPV proteins that can be effectively recognized and presented by the human leukocyte antigen (HLA) system. In the current study, we proposed a synthetic pipeline that integrates computational analysis and experimental assay to discover new peptide epitopes from HPV genome with high affinity to the HLA-A*0201, one of the most frequent HLA allele in Caucasian and Asian populations. In the procedure, a structure-based three-dimensional quantitative structure-activity relationship (3D-QSAR) methodology was described and several 3D-QSAR predictors were established using a set of activity-known HLA binders. The best predictor was then employed to perform extrapolation over the HPV genome to screen potential protein fragments with high HLA binding potency. Consequently, 10 peptides were suggested as promising candidates and their affinities toward HLA-A*0201 were assayed using a standard T2 cell surface stabilization test. Four peptides-LLITSNINA from protein E1 (BL50?=?7244?nM), VLLCVCLLI from protein E5 (BL50?=?9118?nM), VLLLWITAA from protein E5 (BL50?=?3388?nM), and LLMGTLGIV from protein E7 (BL50?=?5500?nM)-were identified as high-affinity binders. Further, the structural basis and binding mode of HLA-A*0201-LLITSNINA complex was examined in detail, revealing a complicated network of nonbonded interactions across the complex interface that should render high stability and specificity for the interaction system. PMID:26418056

  18. Pre-miRNA Loop Nucleotides Control the Distinct Activities of mir-181a-1 and mir-181c in Early T Cell Development

    PubMed Central

    Yue, Sibiao; Chen, Chang-Zheng

    2008-01-01

    Background Mature miRNAs can often be classified into large families, consisting of members with identical seeds (nucleotides 2 through 7 of the mature miRNAs) and highly homologous ?21-nucleotide (nt) mature miRNA sequences. However, it is unclear whether members of a miRNA gene family, which encode identical or nearly identical mature miRNAs, are functionally interchangeable in vivo. Methods and Findings We show that mir-181a-1, but not mir-181c, can promote CD4 and CD8 double-positive (DP) T cell development when ectopically expressed in thymic progenitor cells. The distinct activities of mir-181a-1 and mir-181c are largely determined by their unique pre-miRNA loop nucleotides—not by the one-nucleotide difference in their mature miRNA sequences. Moreover, the activity of mir-181a-1 on DP cell development can be quantitatively influenced by nucleotide changes in its pre-miRNA loop region. We find that both the strength and the functional specificity of miRNA genes can be controlled by the pre-miRNA loop nucleotides. Intriguingly, we note that mutations in the pre-miRNA loop regions affect pre-miRNA and mature miRNA processing, but find no consistent correlation between the effects of pre-miRNA loop mutations on the levels of mature miRNAs and the activities of the mir-181a-1/c genes. Conclusions These results demonstrate that pre-miRNA loop nucleotides play a critical role in controlling the activity of miRNA genes and that members of the same miRNA gene families could have evolved to achieve different activities via alterations in their pre-miRNA loop sequences, while maintaining identical or nearly identical mature miRNA sequences. PMID:18974849

  19. Peripheral canine CD4(+)CD8(+) double-positive T cells - unique amongst others.

    PubMed

    von Buttlar, Heiner; Bismarck, Doris; Alber, Gottfried

    2015-12-15

    T lymphocytes co-expressing CD4 and CD8 ("double-positive T cells") are commonly associated with a thymic developmental stage of T cells. Their first description in humans and pigs as extrathymic T cells with a memory phenotype almost 30 years ago came as a surprise. Meanwhile peripheral double-positive T cells have been described in a growing number of different species. In this review we highlight novel data from our very recent studies on canine peripheral double-positive T cells which point to unique features of double-positive T cells in the dog. In contrast to porcine CD4(+)CD8(+) T cells forming a homogenous cellular population based on their expression of CD4 and CD8?, canine CD4(+)CD8(+) T cells can be divided into three different cellular subsets with distinct expression levels of CD4 and CD8?. Double-positive T cells expressing CD8? are present in humans and dogs but absent in swine. Moreover, canine CD4(+)CD8(+) T cells can not only develop from CD4(+) single-positive T cells but also from CD8(+) single-positive T cells. Together, this places canine CD4(+)CD8(+) T cells closer to their human than porcine counterparts since human double-positive T cells also appear to be heterogeneous in their CD4 and CD8? expression and have both CD4(+) and CD8(+) T cells as progenitor cells. However, CD4(+) single-positive T cells are the more potent progenitors for canine double-positive T cells, whereas CD8(+) single-positive T cells are more potent progenitors for human double-positive T cells. Canine double-positive T cells have an activated phenotype and may have as yet unrecognized roles in vivo in immunity to infection or in inflammatory diseases such as chronic infection, autoimmunity, allergy, or cancer. PMID:26460086

  20. ZFAT plays critical roles in peripheral T cell homeostasis and its T cell receptor-mediated response

    SciTech Connect

    Doi, Keiko; Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka; Central Research Institute of Life Sciences for the Next Generation of Women Scientists, Fukuoka University, Fukuoka ; Fujimoto, Takahiro; Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka ; Okamura, Tadashi; Ogawa, Masahiro; Tanaka, Yoko; Mototani, Yasumasa; Goto, Motohito; Ota, Takeharu; Matsuzaki, Hiroshi; Kuroki, Masahide; Tsunoda, Toshiyuki; Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka ; Sasazuki, Takehiko; Shirasawa, Senji; Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka

    2012-08-17

    Highlights: Black-Right-Pointing-Pointer We generated Cd4-Cre-mediated T cell-specific Zfat-deficient mice. Black-Right-Pointing-Pointer Zfat-deficiency leads to reduction in the number of the peripheral T cells. Black-Right-Pointing-Pointer Impaired T cell receptor-mediated response in Zfat-deficient peripheral T cells. Black-Right-Pointing-Pointer Decreased expression of IL-7R{alpha}, IL-2R{alpha} and IL-2 in Zfat-deficient peripheral T cells. Black-Right-Pointing-Pointer Zfat plays critical roles in peripheral T cell homeostasis. -- Abstract: ZFAT, originally identified as a candidate susceptibility gene for autoimmune thyroid disease, has been reported to be involved in apoptosis, development and primitive hematopoiesis. Zfat is highly expressed in T- and B-cells in the lymphoid tissues, however, its physiological function in the immune system remains totally unknown. Here, we generated the T cell-specific Zfat-deficient mice and demonstrated that Zfat-deficiency leads to a remarkable reduction in the number of the peripheral T cells. Intriguingly, a reduced expression of IL-7R{alpha} and the impaired responsiveness to IL-7 for the survival were observed in the Zfat-deficient T cells. Furthermore, a severe defect in proliferation and increased apoptosis in the Zfat-deficient T cells following T cell receptor (TCR) stimulation was observed with a reduced IL-2R{alpha} expression as well as a reduced IL-2 production. Thus, our findings reveal that Zfat is a critical regulator in peripheral T cell homeostasis and its TCR-mediated response.

  1. B and T cell screen

    MedlinePLUS

    A B and T cell screen is a laboratory test to determine the amount of T and B cells (lymphocytes) in the blood. ... are separated from other blood parts. Once the cells are separated, identifiers are added to distinguish between ...

  2. TGF-? Signalling Is Required for CD4+ T Cell Homeostasis But Dispensable for Regulatory T Cell Function

    PubMed Central

    ?ledzi?ska, Anna; Hemmers, Saskia; Mair, Florian; Gorka, Oliver; Ruland, Jürgen; Fairbairn, Lynsey; Nissler, Anja; Müller, Werner; Waisman, Ari

    2013-01-01

    TGF-? is widely held to be critical for the maintenance and function of regulatory T (Treg) cells and thus peripheral tolerance. This is highlighted by constitutive ablation of TGF-? receptor (TR) during thymic development in mice, which leads to a lethal autoimmune syndrome. Here we describe that TGF-?–driven peripheral tolerance is not regulated by TGF-? signalling on mature CD4+ T cells. Inducible TR2 ablation specifically on CD4+ T cells did not result in a lethal autoinflammation. Transfer of these TR2-deficient CD4+ T cells to lymphopenic recipients resulted in colitis, but not overt autoimmunity. In contrast, thymic ablation of TR2 in combination with lymphopenia led to lethal multi-organ inflammation. Interestingly, deletion of TR2 on mature CD4+ T cells does not result in the collapse of the Treg cell population as observed in constitutive models. Instead, a pronounced enlargement of both regulatory and effector memory T cell pools was observed. This expansion is cell-intrinsic and seems to be caused by increased T cell receptor sensitivity independently of common gamma chain-dependent cytokine signals. The expression of Foxp3 and other regulatory T cells markers was not dependent on TGF-? signalling and the TR2–deficient Treg cells retained their suppressive function both in vitro and in vivo. In summary, absence of TGF-? signalling on mature CD4+ T cells is not responsible for breakdown of peripheral tolerance, but rather controls homeostasis of mature T cells in adult mice. PMID:24115907

  3. Attenuation of Peripheral Regulatory T-Cell Suppression of Skin-Homing CD8+T Cells in Atopic Dermatitis

    PubMed Central

    Zhang, Bao-Xiang; Lyu, Jun-Cheng; Liu, Hai-Bo; Feng, Dian-Qin; Zhang, Dian-Cai; Bi, Xing-Jie; Duan, Zhi-Wu

    2015-01-01

    Purpose Cutaneous lymphocyte-associated antigen (CLA)-expressing CD8+T cells have been known to play an important role in the pathogenesis of atopic dermatitis (AD). However, the mechanisms underlying the loss of self-tolerance remain unclear. Regulatory T cells (Tregs) play a key role in the development of homeostasis in the immune system. We, therefore, hypothesized that a reduced ability of Tregs to inhibit autologous CD8+CLA+T cells might be underlying mechanism in AD. Materials and Methods CD8+CLA+T cells and Tregs were obtained from the peripheral blood of AD patients and control volunteers. The frequencies of CD8+CLA+T cells were evaluated. The proliferative responses of CD8+CLA+T cells were assessed by flow cytometry, and the levels of transforming growth factor-?1 (TGF-?1) and interleukin-10 (IL-10) in culture supernatants were detected by enzyme-linked immunosorbent assay. Results Our results revealed higher frequency and increased expression of perforin and granzyme-B in peripheral CD8+CLA+T cells in AD, and lower inhibitory ability of Tregs on proliferation of CD8+CLA+T cells in AD. Meanwhile, the levels of TGF-?1 produced by Tregs were significantly lower in AD, and anti-TGF-?1 abolished such suppression. Conclusion The attenuated inhibitory ability of Tregs on hyper-activated autologous CD8+CLA+T cells, mediated by TGF-?1, plays an important role in the pathogenesis of AD. PMID:25510765

  4. Rapid and efficient transfer of the T cell aging marker CD57 from glioblastoma stem cells to CAR T cells

    PubMed Central

    Zhu, Xuekai; Niedermann, Gabriele

    2015-01-01

    Adoptive transfer of T cells expressing chimeric antigen receptors (CARs) holds great promise for cancer treatment. We recently developed CAR T cells targeting the prototypic cancer stem cell marker AC133 and showed that these CAR T cells killed AC133+ glioblastoma stem cells (GBM-SCs) in vitro and inhibited the growth of brain tumors initiated from GBM-SCs in xenograft mouse models in vivo. Upon coincubation with GBM-SCs, we observed strong upregulation of the T cell aging marker CD57, but other phenotypical or functional changes usually associated with terminal T cell differentiation could not immediately be detected. Here, we provide evidence suggesting that CD57 is rapidly and efficiently transferred from CD57+ GBM-SCs to preactivated T cells and that the transfer is greatly enhanced by specific CAR/ligand interaction. After separation from CD57+ tumor cells, CD57 epitope expression on T cells decreased only slowly over several days. We conclude that CD57 transfer from tumor cells to T cells may occur in patients with CD57+ tumors and that it may have to be considered in the interpretation of phenotyping results for tumor-infiltrating lymphocytes and perhaps also in the characterization of tumor-specific T cells from tumor or lymph node homogenates or peripheral blood mononuclear cells. PMID:26097880

  5. Calcitriol modulates the CD46 pathway in T cells.

    PubMed

    Kickler, Karoline; Ni Choileain, Siobhan; Williams, Anna; Richards, Anna; Astier, Anne L

    2012-01-01

    The complement regulator CD46 is a costimulatory molecule for human T cells that induces a regulatory Tr1 phenotype, characterized by large amounts of IL-10 secretion. Secretion of IL-10 upon CD46 costimulation is largely impaired in T cells from patients with multiple sclerosis (MS). Vitamin D can exert a direct effect on T cells, and may be beneficial in several pathologies, including MS. In this pilot study, we examined whether active vitamin D (1,25(OH)(2)D(3) or calcitriol) could modulate the CD46 pathway and restore IL-10 production by CD46-costimulated CD4+ T cells from patients with MS. In healthy T cells, calcitriol profoundly affects the phenotype of CD46-costimulated CD4+ T cells, by increasing the expression of CD28, CD25, CTLA-4 and Foxp3 while it concomitantly decreased CD46 expression. Similar trends were observed in MS CD4+ T cells except for CD25 for which a striking opposite effect was observed: while CD25 was normally induced on MS T cells by CD46 costimulation, addition of calcitriol consistently inhibited its induction. Despite the aberrant effect on CD25 expression, calcitriol increased the IL-10:IFN? ratio, characteristic of the CD46-induced Tr1 phenotype, in both T cells from healthy donors and patients with MS. Hence, we show that calcitriol affects the CD46 pathway, and that it promotes anti-inflammatory responses mediated by CD46. Moreover, it might be beneficial for T cell responses in MS. PMID:23144765

  6. C7a, a Biphosphinic Cyclopalladated Compound, Efficiently Controls the Development of a Patient-Derived Xenograft Model of Adult T Cell Leukemia/Lymphoma

    PubMed Central

    Guimaraes-Correa, Ana B.; Crawford, Lindsey B.; Figueiredo, Carlos R.; Gimenes, Karina P.; Pinto, Lorena A.; Rios Grassi, Maria Fernanda; Feuer, Gerold; Travassos, Luiz R.; Caires, Antonio C.F.; Rodrigues, Elaine G.; Marriott, Susan J.

    2011-01-01

    Adult T-cell leukemia/lymphoma (ATLL) is a highly aggressive disease that occurs in individuals infected with the human T lymphotropic virus type 1 (HTLV-1). Patients with aggressive ATLL have a poor prognosis because the leukemic cells are resistant to conventional chemotherapy. We have investigated the therapeutic efficacy of a biphosphinic cyclopalladated complex {Pd2 [S(?)C2, N-dmpa]2 (?-dppe)Cl2}, termed C7a, in a patient-derived xenograft model of ATLL, and investigated the mechanism of C7a action in HTLV-1-positive and negative transformed T cell lines in vitro. In vivo survival studies in immunocompromised mice inoculated with human RV-ATL cells and intraperitoneally treated with C7a led to significantly increased survival of the treated mice. We investigated the mechanism of C7a activity in vitro and found that it induced mitochondrial release of cytochrome c, caspase activation, nuclear condensation and DNA degradation. These results suggest that C7a triggers apoptotic cell death in both HTLV-1 infected and uninfected human transformed T-cell lines. Significantly, C7a was not cytotoxic to peripheral blood mononuclear cells (PBMC) from healthy donors and HTLV-1-infected individuals. C7a inhibited more than 60% of the ex vivo spontaneous proliferation of PBMC from HTLV-1-infected individuals. These results support a potential therapeutic role for C7a in both ATLL and HTLV-1-negative T-cell lymphomas. PMID:21994769

  7. Sleeping Beauty Transposition of Chimeric Antigen Receptors Targeting Receptor Tyrosine Kinase-Like Orphan Receptor-1 (ROR1) into Diverse Memory T-Cell Populations

    PubMed Central

    Deniger, Drew C.; Yu, Jianqiang; Huls, M. Helen; Figliola, Matthew J.; Mi, Tiejuan; Maiti, Sourindra N.; Widhopf, George F.; Hurton, Lenka V.; Thokala, Radhika; Singh, Harjeet; Olivares, Simon; Champlin, Richard E.; Wierda, William G.; Kipps, Thomas J.; Cooper, Laurence J. N.

    2015-01-01

    T cells modified with chimeric antigen receptors (CARs) targeting CD19 demonstrated clinical activity against some B-cell malignancies. However, this is often accompanied by a loss of normal CD19+ B cells and humoral immunity. Receptor tyrosine kinase-like orphan receptor-1 (ROR1) is expressed on sub-populations of B-cell malignancies and solid tumors, but not by healthy B cells or normal post-partum tissues. Thus, adoptive transfer of T cells specific for ROR1 has potential to eliminate tumor cells and spare healthy tissues. To test this hypothesis, we developed CARs targeting ROR1 in order to generate T cells specific for malignant cells. Two Sleeping Beauty transposons were constructed with 2nd generation ROR1-specific CARs signaling through CD3? and either CD28 (designated ROR1RCD28) or CD137 (designated ROR1RCD137) and were introduced into T cells. We selected for T cells expressing CAR through co-culture with ?-irradiated activating and propagating cells (AaPC), which co-expressed ROR1 and co-stimulatory molecules. Numeric expansion over one month of co-culture on AaPC in presence of soluble interleukin (IL)-2 and IL-21 occurred and resulted in a diverse memory phenotype of CAR+ T cells as measured by non-enzymatic digital array (NanoString) and multi-panel flow cytometry. Such T cells produced interferon-? and had specific cytotoxic activity against ROR1+ tumors. Moreover, such cells could eliminate ROR1+ tumor xenografts, especially T cells expressing ROR1RCD137. Clinical trials will investigate the ability of ROR1-specific CAR+ T cells to specifically eliminate tumor cells while maintaining normal B-cell repertoire. PMID:26030772

  8. Involvement of the interleukin 4 pathway in the generation of functional gamma delta T cells from human pro-T cells.

    PubMed Central

    Bárcena, A; Sánchez, M J; de la Pompa, J L; Toribio, M L; Kroemer, G; Martínez-A, C

    1991-01-01

    We have used the technique of in situ hybridization to investigate the transcription of genes encoding the CD3 complex and the lymphokine interleukin 4 (IL-4) by human pro-T cells--i.e., cells that phenotypically resemble those T-cell precursors that colonize the thymus during early intrathymic development. CD1-2-3-4-7+8-45+ pro-T cells isolated from postnatal thymi via immunoselection with a panel of specific monoclonal antibodies are already committed to the T-cell lineage because most of them transcribe the genes encoding the delta and epsilon chains of the CD3 complex. About half of such pro-T cells synthesize IL-4 mRNA in the absence of any exogenous stimulation. Upon culture with IL-4, pro-T cells extensively proliferate and differentiate into functionally competent, mature gamma delta T cells expressing a T-cell receptor repertoire similar to that of gamma delta T cells that can be found in postnatal thymus. The IL-4 response of pro-T cells is not mediated by induction of the interleukin 2 (IL-2)-IL-2 receptor pathway and, unlike IL-2-driven T-cell differentiation, does not require the presence of stromal cells. Taken altogether, these findings suggest that an autocrine IL-4-mediated pathway might be implicated in early thymocyte differentiation--namely, in the generation of T cells bearing the gamma delta T-cell receptor. Images PMID:1881911

  9. Live imaging of LFA-1-dependent T-cell motility and stop signals.

    PubMed

    Wiemer, Andrew J; Wernimont, Sarah; Huttenlocher, Anna

    2012-01-01

    T-cell motility is critical for leukocyte trafficking both in normal host defense and in pathologic conditions including chronic inflammatory disease. Despite progress in understanding the mechanisms of T-cell polarity and motility, we have limited understanding of the mechanisms that contribute to antigen-induced T cell arrest. Here, we describe methods to analyze leukocyte function antigen-1-mediated T-cell motility and T-cell receptor-induced stop signals using in vitro assays on two-dimensional surfaces. Specifically, methods for live time-lapse imaging of T cell random migration and arrest on ICAM-1-coated surfaces are described. Additionally, we detail methods for live imaging of T-cell motility within 3D substrates to analyze T cell-antigen-presenting cell (APC) interactions and APC-mediated stop signals. PMID:21909914

  10. Interleukin 17-Producing ??T Cells Promote Hepatic Regeneration in Mice

    PubMed Central

    Rao, Raghavendra; Graffeo, Christopher S.; Gulati, Rishabh; Jamal, Mohsin; Narayan, Suchithra; Zambirinis, Constantinos; Barilla, Rocky; Deutsch, Michael; Greco, Stephanie; Ochi, Atsuo; Tomkötter, Lena; Blobstein, Reuven; Avanzi, Antonina; Tippens, Daniel M.; Gelbstein, Yisroel; Heerden, Eliza Van; Miller, George

    2014-01-01

    Background & Aims Subsets of leukocytes synergize with regenerative growth factors to promote hepatic regeneration. ??T cells are early responders to inflammation-induced injury in a number of contexts. We investigated the role of ??T cells in hepatic regeneration using mice with disruptions in Tcrd (encodes the T cell receptor ? chain) and Clec7a (encodes C-type lectin domain family 7 member a, also known as DECTIN1). Methods We performed partial hepatectomies on wild-type C57BL/6, CD45.1, Tcrd?/?, or Clec7a?/? mice. Cells were isolated from livers of patients and mice via mechanical and enzymatic digestion. ??T cells were purified by fluorescence-activated cell sorting. Results In mice, partial hepatectomy upregulated expression of CCL20 and ligands of Dectin-1, associated with recruitment and activation of ??T cells and their increased production of interleukin (IL)17 family cytokines. Recruited ??T cells induced production of IL6 by antigen-presenting cells and suppressed expression of interferon ? by natural killer T cells, promoting hepatocyte proliferation. Absence of IL17-producing ??T cells or deletion of Dectin-1 prevented development of regenerative phenotypes in subsets of innate immune cells. This slowed liver regeneration and was associated with reduced expression of regenerative growth factors and cell cycle regulators. Conversely, exogenous administration of IL17 family cytokines or Dectin-1 ligands promoted regeneration. More broadly, we found that ??T cells are required for inflammatory responses mediated by IL17 and Dectin-1. Conclusions ??T cells regulate hepatic regeneration by producing IL22 and IL17, which have direct mitogenic effects on hepatocytes and promote a regenerative phenotype in hepatic leukocytes, respectively. Dectin-1 ligation is required for ??T cells to promote hepatic regeneration. PMID:24801349

  11. Characterization and Isolation of Human T Cell Progenitors.

    PubMed

    Van de Walle, Inge; Davids, Karin; Taghon, Tom

    2016-01-01

    During their development, human T cells undergo similar genomic changes and pass through the same developmental checkpoints as developing thymocytes in the mouse. The difference between both species, however, is that some of these developmental stages are characterized by different phenotypic markers and as a result, evidence emerges that the molecular regulation of human T cell development subtly differs from the mouse [1-4]. In this chapter, we describe in detail how the different stages of human T cell development can be characterized and isolated using specific surface markers. PMID:26294412

  12. Integrin ?E(CD103) Is Involved in Regulatory T-Cell Function in Allergic Contact Hypersensitivity.

    PubMed

    Braun, Andrea; Dewert, Nadin; Brunnert, Fiona; Schnabel, Viktor; Hardenberg, Jan-Hendrik; Richter, Beatrice; Zachmann, Karolin; Cording, Sascha; Claßen, Anna; Brans, Richard; Hamann, Alf; Huehn, Jochen; Schön, Michael P

    2015-12-01

    Murine contact hypersensitivity (CHS) is a dendritic cell (DC)-dependent T-cell-mediated inflammation with CD8(+) T cells as effectors and CD4(+) T cells as regulators (Treg cells) that models human allergic contact dermatitis. The integrin ?E(CD103) is expressed by some T-cell and DC subsets and has been implicated in epithelial lymphocyte localization, but its role in immune regulation remains enigmatic. We have identified a function for CD103 in the development of cutaneous allergic immune responses. CHS responses, but not irritant contact dermatitis, were significantly augmented in CD103-deficient mice in hapten-challenged skin. Phenotype and function of skin DCs during sensitization were normal, whereas adoptive transfer experiments revealed that the elevated CHS response in CD103-deficient mice is transferred by primed T cells and is independent of resident cells in recipient mice. While T-cell counts were elevated in challenged skin of CD103-deficient mice, the FoxP3 expression level of CD4(+)CD25(+) Treg cells was significantly reduced, indicating impaired functionality. Indeed, Treg cells from CD103-deficient mice were not able to suppress CHS reactions during the elicitation phase. Further, CD103 on FoxP3(+) Treg cells was involved in Treg retention to inflamed skin. These findings indicate an unexpected dichotomous functional role for CD103 on Treg cells by modulating FoxP3 expression. PMID:26203637

  13. The burgeoning family of unconventional T cells.

    PubMed

    Godfrey, Dale I; Uldrich, Adam P; McCluskey, James; Rossjohn, Jamie; Moody, D Branch

    2015-10-20

    While most studies of T lymphocytes have focused on T cells reactive to complexes of peptide and major histocompatibility complex (MHC) proteins, many other types of T cells do not fit this paradigm. These include CD1-restricted T cells, MR1-restricted mucosal associated invariant T cells (MAIT cells), MHC class Ib-reactive T cells, and ?? T cells. Collectively, these T cells are considered 'unconventional', in part because they can recognize lipids, small-molecule metabolites and specially modified peptides. Unlike MHC-reactive T cells, these apparently disparate T cell types generally show simplified patterns of T cell antigen receptor (TCR) expression, rapid effector responses and 'public' antigen specificities. Here we review evidence showing that unconventional T cells are an abundant component of the human immune system and discuss the immunotherapeutic potential of these cells and their antigenic targets. PMID:26482978

  14. Natural regulatory T cells are resistant to calcium release-activated calcium (CRAC/ORAI) channel inhibition.

    PubMed

    Jin, Shu; Chin, Jayne; Kitson, Christopher; Woods, John; Majmudar, Rupal; Carvajal, Valerie; Allard, John; Demartino, Julie; Narula, Satwant; Thomas-Karyat, Dori A

    2013-09-01

    Organ transplant patients are often treated with immunosuppressants, such as the calcineurin phosphatase inhibitor, cyclosporin A, to block T cell-mediated graft rejection. The calcium release-activated calcium (CRAC/ORAI) channels, which act upstream of calcineurin, are essential for calcium entry and CD4(+) T-cell activation. Although cyclosporine A has also been shown to inhibit FoxP3(+) Tregs both in vitro and in vivo, the role of ORAI channel inhibition in natural Tregs (nTregs) or inducible Tregs (iTregs) has not been investigated. We found that, despite inhibition of calcium influx through the ORAI channels, ORAI channel inhibitors were unable to repress FoxP3 expression in mouse and human nTregs, whereas FoxP3 expression was inhibited in iTregs. In contrast, cyclosporin A inhibited FoxP3 expression in both nTregs and iTregs. We also generated mice with a T cell-specific, conditional knockout of ORAI1 and found that the mice have normal nTreg development and suppressive activity. Moreover, iTregs derived from ORAI1 conditional knockout mice develop normally and are still susceptible to ORAI channel inhibition. Our data indicate that unlike CD4(+) T cells and iTregs, nTregs are resistant to ORAI-mediated inhibition. Targeting ORAI channels potentially offers a novel way to inhibit pathologic T cells, while sparing nTreg-mediated tolerance. PMID:23667148

  15. STAT3 is a critical cell-intrinsic regulator of human unconventional T cell numbers and function

    PubMed Central

    Wilson, Robert P.; Ives, Megan L.; Rao, Geetha; Lau, Anthony; Payne, Kathryn; Kobayashi, Masao; Arkwright, Peter D.; Peake, Jane; Wong, Melanie; Adelstein, Stephen; Smart, Joanne M.; French, Martyn A.; Fulcher, David A.; Picard, Capucine; Bustamante, Jacinta; Boisson-Dupuis, Stephanie; Gray, Paul; Stepensky, Polina; Warnatz, Klaus; Freeman, Alexandra F.; Rossjohn, Jamie; McCluskey, James; Holland, Steven M.; Casanova, Jean-Laurent; Uzel, Gulbu; Ma, Cindy S.

    2015-01-01

    Unconventional T cells such as ?? T cells, natural killer T cells (NKT cells) and mucosal-associated invariant T cells (MAIT cells) are a major component of the immune system; however, the cytokine signaling pathways that control their development and function in humans are unknown. Primary immunodeficiencies caused by single gene mutations provide a unique opportunity to investigate the role of specific molecules in regulating human lymphocyte development and function. We found that individuals with loss-of-function mutations in STAT3 had reduced numbers of peripheral blood MAIT and NKT but not ?? T cells. Analysis of STAT3 mosaic individuals revealed that this effect was cell intrinsic. Surprisingly, the residual STAT3-deficient MAIT cells expressed normal levels of the transcription factor ROR?t. Despite this, they displayed a deficiency in secretion of IL-17A and IL-17F, but were able to secrete normal levels of cytokines such as IFN? and TNF. The deficiency in MAIT and NKT cells in STAT3-deficient patients was mirrored by loss-of-function mutations in IL12RB1 and IL21R, respectively. Thus, these results reveal for the first time the essential role of STAT3 signaling downstream of IL-23R and IL-21R in controlling human MAIT and NKT cell numbers. PMID:25941256

  16. STAT3 is a critical cell-intrinsic regulator of human unconventional T cell numbers and function.

    PubMed

    Wilson, Robert P; Ives, Megan L; Rao, Geetha; Lau, Anthony; Payne, Kathryn; Kobayashi, Masao; Arkwright, Peter D; Peake, Jane; Wong, Melanie; Adelstein, Stephen; Smart, Joanne M; French, Martyn A; Fulcher, David A; Picard, Capucine; Bustamante, Jacinta; Boisson-Dupuis, Stephanie; Gray, Paul; Stepensky, Polina; Warnatz, Klaus; Freeman, Alexandra F; Rossjohn, Jamie; McCluskey, James; Holland, Steven M; Casanova, Jean-Laurent; Uzel, Gulbu; Ma, Cindy S; Tangye, Stuart G; Deenick, Elissa K

    2015-06-01

    Unconventional T cells such as ?? T cells, natural killer T cells (NKT cells) and mucosal-associated invariant T cells (MAIT cells) are a major component of the immune system; however, the cytokine signaling pathways that control their development and function in humans are unknown. Primary immunodeficiencies caused by single gene mutations provide a unique opportunity to investigate the role of specific molecules in regulating human lymphocyte development and function. We found that individuals with loss-of-function mutations in STAT3 had reduced numbers of peripheral blood MAIT and NKT but not ?? T cells. Analysis of STAT3 mosaic individuals revealed that this effect was cell intrinsic. Surprisingly, the residual STAT3-deficient MAIT cells expressed normal levels of the transcription factor ROR?t. Despite this, they displayed a deficiency in secretion of IL-17A and IL-17F, but were able to secrete normal levels of cytokines such as IFN? and TNF. The deficiency in MAIT and NKT cells in STAT3-deficient patients was mirrored by loss-of-function mutations in IL12RB1 and IL21R, respectively. Thus, these results reveal for the first time the essential role of STAT3 signaling downstream of IL-23R and IL-21R in controlling human MAIT and NKT cell numbers. PMID:25941256

  17. Structural and biophysical determinants of ?? T-cell antigen recognition

    PubMed Central

    Bridgeman, John S; Sewell, Andrew K; Miles, John J; Price, David A; Cole, David K

    2012-01-01

    The molecular rules that govern MHC restriction, and allow T-cells to differentiate between peptides derived from healthy cells and those from diseased cells, remain poorly understood. Here we provide an overview of the structural constraints that enable the T-cell receptor (TCR) to discriminate between self and non-self peptides, and summarize studies that have attempted to correlate the biophysical parameters of TCR/peptide–major histocompatibility complex (pMHC) binding with T-cell activation. We further review how the antigenic origin of peptide epitopes affects TCR binding parameters and the ‘quality’ of a T-cell response. Understanding the principles that govern pMHC recognition by T-cells will unlock pathways to the rational development of immunotherapeutic approaches for the treatment of infectious disease, cancer and autoimmunity. PMID:22044041

  18. CRTAM is negatively regulated by ZEB1 in T cells.

    PubMed

    Rojas-Marquez, C; Valle-Rios, R; Lopez-Bayghen, E; Ortiz-Navarrete, V

    2015-08-01

    T cell activation leads to the induction of genes that are required for appropriate immune responses. This includes CRTAM (Class-I MHC-restricted T cell associated molecule), a protein that plays a key role in T cell development, proliferation, and generating cell polarity during activation. We previously characterized the CRTAM promoter and described how AP-1 family members are important for inducing CRTAM expression upon antigenic activation. Here, we show that CRTAM is a molecular target for ZEB1 (zinc finger E-box-binding protein), a homeodomain/Zn finger transcription factor. Overexpression of ZEB1 repressed CRTAM promoter activity, as well as endogenous CRTAM levels in human T cells. ZEB1-mediated transcriptional repression was abolished when E-box-like elements in the CRTAM promoter are mutated. In summary, ZEB1 functions as a transcriptional repressor for the CRTAM gene in both non-stimulated and stimulated T cells, thereby modulating adaptive immune responses. PMID:25910959

  19. Cytoskeletal forces during signaling activation in Jurkat T-cells

    PubMed Central

    Hui, King Lam; Balagopalan, Lakshmi; Samelson, Lawrence E.; Upadhyaya, Arpita

    2015-01-01

    T-cells are critical for the adaptive immune response in the body. The binding of the T-cell receptor (TCR) with antigen on the surface of antigen-presenting cells leads to cell spreading and signaling activation. The underlying mechanism of signaling activation is not completely understood. Although cytoskeletal forces have been implicated in this process, the contribution of different cytoskeletal components and their spatial organization are unknown. Here we use traction force microscopy to measure the forces exerted by Jurkat T-cells during TCR activation. Perturbation experiments reveal that these forces are largely due to actin assembly and dynamics, with myosin contractility contributing to the development of force but not its maintenance. We find that Jurkat T-cells are mechanosensitive, with cytoskeletal forces and signaling dynamics both sensitive to the stiffness of the substrate. Our results delineate the cytoskeletal contributions to interfacial forces exerted by T-cells during activation. PMID:25518938

  20. Loss of T cell precursors after spaceflight and exposure to vector-averaged gravity

    NASA Technical Reports Server (NTRS)

    Woods, Chris C.; Banks, Krista E.; Gruener, Raphael; DeLuca, Dominick

    2003-01-01

    Using fetal thymus organ culture (FTOC), we examined the effects of spaceflight and vector-averaged gravity on T cell development. Under both conditions, the development of T cells was significantly attenuated. Exposure to spaceflight for 16 days resulted in a loss of precursors for CD4+, CD8+, and CD4+CD8+ T cells in a rat/mouse xenogeneic co-culture. A significant decrease in the same precursor cells, as well as a decrease in CD4-CD8- T cell precursors, was also observed in a murine C57BL/6 FTOC after rotation in a clinostat to produce a vector-averaged microgravity-like environment. The block in T cell development appeared to occur between the pre-T cell and CD4+CD8+ T cell stage. These data indicate that gravity plays a decisive role in the development of T cells.

  1. Impact of sepsis on CD4 T cell immunity

    PubMed Central

    Cabrera-Perez, Javier; Condotta, Stephanie A.; Badovinac, Vladimir P.; Griffith, Thomas S.

    2014-01-01

    Sepsis remains the primary cause of death from infection in hospital patients, despite improvements in antibiotics and intensive-care practices. Patients who survive severe sepsis can display suppressed immune function, often manifested as an increased susceptibility to (and mortality from) nosocomial infections. Not only is there a significant reduction in the number of various immune cell populations during sepsis, but there is also decreased function in the remaining lymphocytes. Within the immune system, CD4 T cells are important players in the proper development of numerous cellular and humoral immune responses. Despite sufficient clinical evidence of CD4 T cell loss in septic patients of all ages, the impact of sepsis on CD4 T cell responses is not well understood. Recent findings suggest that CD4 T cell impairment is a multipronged problem that results from initial sepsis-induced cell loss. However, the subsequent lymphopenia-induced numerical recovery of the CD4 T cell compartment leads to intrinsic alterations in phenotype and effector function, reduced repertoire diversity, changes in the composition of naive antigen-specific CD4 T cell pools, and changes in the representation of different CD4 T cell subpopulations (e.g., increases in Treg frequency). This review focuses on sepsis-induced alterations within the CD4 T cell compartment that influence the ability of the immune system to control secondary heterologous infections. The understanding of how sepsis affects CD4 T cells through their numerical loss and recovery, as well as function, is important in the development of future treatments designed to restore CD4 T cells to their presepsis state. PMID:24791959

  2. Intercellular Adhesion Molecule-1 Guides Naive T Cell Differentiation and Regulatory T Cell Induction

    E-print Network

    Williams, Kelli M.

    2012-12-31

    Genet 27: 20-1 40. Fontenot JD, Gavin MA, Rudensky AY. 2003. Foxp3 programs the development and function of CD4+CD25+ regulatory T cells. Nat Immunol 4: 330-6 41. Huehn J, Polansky JK, Hamann A. 2009. Epigenetic control of FOXP3 expression: the key...). Refer to Protocol 1 in the Appendix for more detail. In selected experiments where indicated, naïve CD4+ T cells were isolated from human tonsil tissue. In summary, tonsils were minced over a strainer to obtain cell suspensions, mononuclear cells...

  3. Long-lived virus-reactive memory T cells generated from purified cytokine-secreting T helper type 1 and type 2 effectors

    PubMed Central

    Löhning, Max; Hegazy, Ahmed N.; Pinschewer, Daniel D.; Busse, Dorothea; Lang, Karl S.; Höfer, Thomas; Radbruch, Andreas; Zinkernagel, Rolf M.; Hengartner, Hans

    2008-01-01

    Many vaccination strategies and immune cell therapies aim at increasing the numbers of memory T cells reactive to protective antigens. However, the differentiation lineage and therefore the optimal generation conditions of CD4 memory cells remain controversial. Linear and divergent differentiation models have been proposed, suggesting CD4 memory T cell development from naive precursors either with or without an effector-stage intermediate, respectively. Here, we address this question by using newly available techniques for the identification and isolation of effector T cells secreting effector cytokines. In adoptive cell transfers into normal, nonlymphopenic mice, we show that long-lived virus-specific memory T cells can efficiently be generated from purified interferon ?–secreting T helper (Th) type 1 and interleukin (IL)-4– or IL-10–secreting Th2 effectors primed in vitro or in vivo. Importantly, such effector-derived memory T cells were functional in viral challenge infections. They proliferated vigorously, rapidly modulated IL-7 receptor expression, exhibited partial stability and flexibility of their cytokine patterns, and exerted differential effects on virus-induced immunopathology. Thus, cytokine-secreting effectors can evade activation-induced cell death and develop into long-lived functional memory cells. These findings demonstrate the efficiency of linear memory T cell differentiation and encourage the design of vaccines and immune cell therapies based on differentiated effector T cells. PMID:18195073

  4. Long-lived virus-reactive memory T cells generated from purified cytokine-secreting T helper type 1 and type 2 effectors.

    PubMed

    Löhning, Max; Hegazy, Ahmed N; Pinschewer, Daniel D; Busse, Dorothea; Lang, Karl S; Höfer, Thomas; Radbruch, Andreas; Zinkernagel, Rolf M; Hengartner, Hans

    2008-01-21

    Many vaccination strategies and immune cell therapies aim at increasing the numbers of memory T cells reactive to protective antigens. However, the differentiation lineage and therefore the optimal generation conditions of CD4 memory cells remain controversial. Linear and divergent differentiation models have been proposed, suggesting CD4 memory T cell development from naive precursors either with or without an effector-stage intermediate, respectively. Here, we address this question by using newly available techniques for the identification and isolation of effector T cells secreting effector cytokines. In adoptive cell transfers into normal, nonlymphopenic mice, we show that long-lived virus-specific memory T cells can efficiently be generated from purified interferon gamma-secreting T helper (Th) type 1 and interleukin (IL)-4- or IL-10-secreting Th2 effectors primed in vitro or in vivo. Importantly, such effector-derived memory T cells were functional in viral challenge infections. They proliferated vigorously, rapidly modulated IL-7 receptor expression, exhibited partial stability and flexibility of their cytokine patterns, and exerted differential effects on virus-induced immunopathology. Thus, cytokine-secreting effectors can evade activation-induced cell death and develop into long-lived functional memory cells. These findings demonstrate the efficiency of linear memory T cell differentiation and encourage the design of vaccines and immune cell therapies based on differentiated effector T cells. PMID:18195073

  5. Regulatory T cells prevent control of experimental African trypanosomiasis.

    PubMed

    Wei, Guojian; Tabel, Henry

    2008-02-15

    African trypanosomes are single-cell, extra-cellular blood parasites causing profound immunosuppression. Susceptible BALB/c mice infected s.c. into a footpad with 10(4) Trypanosoma congolense die with fulminating parasitemia within 10 days. We injected BALB/c mice 2 days before such an infection with different doses of a depleting mAb specific for CD25, a surface marker of regulatory T cells (Tregs). Pretreatment with a low, optimal dose of anti-CD25 resulted in a dramatic effect, in that the infected mice did not develop parasitemia, as well as eliminated all parasites and showed no signs of disease. Their spleens showed a 100% reduction of CD4(+)CD25(high) T cells and overall a 70% reduction of CD4(+)CD25(+)Foxp3(+) T cells 7 days postinfection. The protective effect of treatment with an optimal dose of anti-CD25 could be reversed by administration of l-N6-(1-imminoethyl) lysine, a specific inhibitor of inducible NO synthase or administration of anti-CD8 Ab. Analysis of the cytokine patterns and cell surface marker in infected mice pretreated with anti-CD25 Abs pointed to a potential NKT cell response. We then conducted infections in CD1d(-/-) mice. From our observations, we conclude that CD4(+)CD25(high)Foxp3(+) Tregs prevent, in normal infected susceptible mice, an early protective response mediated by CD8(+) NKT cell-dependent activation of macrophages to kill parasites by production of NO. Our results also indicate that different populations of NKT cells have protective or suppressive effects. Our observations lead us to propose a hypothesis of cross-regulation of NKT cells and Tregs in trypanosome infections. PMID:18250461

  6. CMV-Specific T-cells Generated From Naïve T-cells Recognize Atypical Epitopes And May Be Protective in Vivo

    PubMed Central

    Hanley, Patrick J.; Melenhorst, Jan J.; Nikiforow, Sarah; Scheinberg, Phillip; Blaney, James W.; Demmler-Harrison, Gail; Cruz, C. Russell; Lam, Sharon; Krance, Robert A.; Leung, Kathryn S.; Martinez, Caridad A.; Liu, Hao; Heslop, Helen E.; Rooney, Cliona M.; Shpall, Elizabeth J.; Barrett, A. John; Rodgers, John R.; Bollard, Catherine M.

    2015-01-01

    Adoptive transfer of adult-seropositive, cytomegalovirus (CMV)-specific T-cells can effectively restore antiviral immunity after transplantation. Lack of CMV-specific memory T-cells in blood from CMV-seronegative adult and cord blood (CB) donors restricts the availability of donor-derived virus-specific T-cells for immunoprophylaxis. Here we demonstrate the feasibility of naïve-donor-derived CMV-specific T-cell therapy for transplant recipients. Primed naïve T-cells recognized only atypical epitopes and with a similar avidity to CMV-seropositive-derived T-cells recognizing typical epitopes, but T-cells from CMV-seropositive donors recognizing atypical epitopes had a lower avidity suggesting the loss of high-avidity T-cells over time. Clonotypic analysis revealed T-cells recognizing atypical CMVpp65 epitopes in the peripheral blood of recipients of CB grafts who did not develop CMV. T-cell receptors from atypical epitopes were most common in unmanipulated CB units explaining why these T-cells expanded. When infused to recipients, naïve donor-derived virus specific T-cells that recognized atypical epitopes were associated with prolonged periods of CMV-free survival and complete remission. PMID:25925682

  7. Notch signalling in T cell lymphoblastic leukaemia/lymphoma and other haematological malignancies

    PubMed Central

    Aster, Jon C.; Blacklow, Stephen C.; Pear, Warren S.

    2010-01-01

    Notch receptors participate in a highly conserved signalling pathway that regulates normal development and tissue homeostasis in a context- and dose-dependent manner. Deregulated Notch signalling has been implicated in many diseases, but the clearest example of a pathogenic role is found in T cell lymphoblastic leukaemia/lymphoma (T-LL), in which the majority of human and murine tumours have acquired mutations that lead to aberrant increases in Notch1 signalling. Remarkably, it appears that the selective pressure for Notch mutations is virtually unique among cancers to T-LL, presumably reflecting a special context-dependent role for Notch in normal T cell progenitors. Nevertheless, there are some recent reports suggesting that Notch signalling has subtle yet important roles in other forms of hematologic malignancy as well. Here, we review the role of Notch signalling in various blood cancers, focusing on T-LL with an eye toward targeted therapeutics. PMID:20967796

  8. Fish T cells: recent advances through genomics

    USGS Publications Warehouse

    Laing, Kerry J.; Hansen, John D.

    2011-01-01

    This brief review is intended to provide a concise overview of the current literature concerning T cells, advances in identifying distinct T cell functional subsets, and in distinguishing effector cells from memory cells. We compare and contrast a wealth of recent progress made in T cell immunology of teleost, elasmobranch, and agnathan fish, to knowledge derived from mammalian T cell studies. From genome studies, fish clearly have most components associated with T cell function and we can speculate on the presence of putative T cell subsets, and the ability to detect their differentiation to form memory cells. Some recombinant proteins for T cell associated cytokines and antibodies for T cell surface receptors have been generated that will facilitate studying the functional roles of teleost T cells during immune responses. Although there is still a long way to go, major advances have occurred in recent years for investigating T cell responses, thus phenotypic and functional characterization is on the near horizon.

  9. The development of peripheral T-cell lymphoma after successful treatment for diffuse large B-cell lymphoma in a patient with suspected adult onset immunodeficiency: more questions than answers?

    PubMed Central

    Kilner, Mari Frances; Merante, Serena; Svec, Alexandr

    2013-01-01

    We present the case of a 60-year-old woman who developed peripheral T-cell lymphoma following successful treatment for high-grade B-cell non-Hodgkin's lymphoma. We consider the possible aetiology of this unusual occurrence. We hypothesise that this case represents one of the undiagnosed adult-onset immunodeficiency, in which the pathogenesis of the patient's T-cell lymphoma may have been in part iatrogenic, namely related to previous immunotherapy with rituximab. We feel this case highlights the importance of rebiopsy in patients with recurrent lymphadenopathy and a history of haematological malignancy and hence acts as an important aide memoir in the investigation of such cases. PMID:24343800

  10. Dynamics of HIV infection of CD4[sup +] T cells

    SciTech Connect

    Perelson, A.S.; De Boer, R. ); Kirschner, D.E. )

    1993-03-01

    The authors examine a model for the interaction of HIV with CD4[sup +] T cells that considers four populations: uninfected T cells, latently infected T cells, actively infected T cells, and free virus. Using this model they show that many of the puzzling quantitative features of HIV infection can be explained simply. They also consider effects of AZT on viral growth and T-cell population dynamics. The model exhibits two steady states, an uninfected state in which no virus is present and an endemically infected state, in which virus and infected T cells are present. They show that if N, the number of infections virions produced per actively infected T cell, is less a critical value, N[sub crit], then the uninfected state is the only steady state in the nonnegative orthant, and this state is stable. For N > N[sub crit], the uninfected state is unstable, and the endemically infected state can be either stable, or unstable and surrounded by a stable limit cycle. Using numerical bifurcation techniques they map out the parameter regimes of these various behaviors. Oscillatory behavior seems to lie outside the region of biologically realistic parameter value. When the endemically infected state is stable, it is characterized by a reduced number of T cells compared with the uninfected state. Thus T-cell depletion occurs through the establishment of a new steady state. The dynamics of the establishment of this new steady state are examined both numerically and via the quasi-steady-state approximation. They develop approximations for the dynamics at early times in which the free virus rapidly binds to T cells, during an intermediate time scale in which the virus grows exponentially, and a third time scale on which viral growth slows and the endemically infected steady state is approached. Using the quasi-steady-state approximation the model can be simplified to two ordinary differential equations that summarize much of the dynamical behavior. 65 refs., 14 figs., 2 tabs.

  11. BOOK REVIEW The Kidney: From Normal Development to Congenital Disease

    E-print Network

    Vize, Peter D.

    BOOK REVIEW The Kidney: From Normal Development to Congenital Disease Editors: Peter D. Vize that deifies the kidney as the master organ of evolution that has made terrestrial life possible for us. The Kidney: From Normal Development to Congenital Disease, edited by Peter Vize, Adrian Woolf, and Johnathan

  12. Chapter 2. Normal Plant Appearance and Development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most often, agronomists evaluate crop health by examining aboveground plant growth and canopy appearance. It is important to know when stresses occur relative to critical events in the development of the crop. This enables an agronomist to more effectively and efficiently employ management practices...

  13. T Cell Responses against Mycobacterial Lipids and Proteins Are Poorly Correlated in South African Adolescents.

    PubMed

    Seshadri, Chetan; Lin, Lin; Scriba, Thomas J; Peterson, Glenna; Freidrich, David; Frahm, Nicole; DeRosa, Stephen C; Moody, D Branch; Prandi, Jacques; Gilleron, Martine; Mahomed, Hassan; Jiang, Wenxin; Finak, Greg; Hanekom, Willem A; Gottardo, Raphael; McElrath, M Juliana; Hawn, Thomas R

    2015-11-15

    Human T cells are activated by both peptide and nonpeptide Ags produced by Mycobacterium tuberculosis. T cells recognize cell wall lipids bound to CD1 molecules, but effector functions of CD1-reactive T cells have not been systematically assessed in M. tuberculosis-infected humans. It is also not known how these features correlate with T cell responses to secreted protein Ags. We developed a flow cytometric assay to profile CD1-restricted T cells ex vivo and assessed T cell responses to five cell wall lipid Ags in a cross-sectional study of 19 M. tuberculosis-infected and 22 M. tuberculosis-uninfected South African adolescents. We analyzed six T cell functions using a recently developed computational approach for flow cytometry data in high dimensions. We compared these data with T cell responses to five protein Ags in the same cohort. We show that CD1b-restricted T cells producing antimycobacterial cytokines IFN-? and TNF-? are detectable ex vivo in CD4(+), CD8(+), and CD4(-)CD8(-) T cell subsets. Glucose monomycolate was immunodominant among lipid Ags tested, and polyfunctional CD4 T cells specific for this lipid simultaneously expressed CD40L, IFN-?, IL-2, and TNF-?. Lipid-reactive CD4(+) T cells were detectable at frequencies of 0.001-0.01%, and this did not differ by M. tuberculosis infection status. Finally, CD4 T cell responses to lipids were poorly correlated with CD4 T cell responses to proteins (Spearman rank correlation -0.01; p = 0.95). These results highlight the functional diversity of CD1-restricted T cells circulating in peripheral blood as well as the complementary nature of T cell responses to mycobacterial lipids and proteins. Our approach enables further population-based studies of lipid-specific T cell responses during natural infection and vaccination. PMID:26466957

  14. Rapid Isolation of Central Memory T Cells for Adoptive Immunotherapy

    Cancer.gov

    The National Cancer Institute (NCI), Surgery Branch is seeking parties interested in collaborative research to further co-develop a methodology for the isolation of memory T cells for adoptive immunotherapy.

  15. Multi-scale models of T cell activation

    E-print Network

    Zheng, Huan, Ph.D. Massachusetts Institute of Technology

    2010-01-01

    The overarching theme of this thesis is to develop and apply multi-scale computational techniques adopted from physical sciences to study a key phenomenon underlying the adaptive immune response: the activation of T cells. ...

  16. Stromal-Derived Factor-1? and Interleukin-7 Treatment Improves Homeostatic Proliferation of Naïve CD4(+) T Cells after Allogeneic Stem Cell Transplantation.

    PubMed

    Gauthier, Simon-David; Leboeuf, Dominique; Manuguerra-Gagné, Renaud; Gaboury, Louis; Guimond, Martin

    2015-10-01

    Graft-versus-host disease (GVHD) impairs immune reconstitution after allogeneic stem cell transplantation (allo-SCT) and effective therapies aimed at restoring T cell counts in GVHD patients have yet to be developed. During GVHD, CD4(+) T cell reconstitution is particularly affected and current models hold that GVHD insult to the peripheral lymphoid niche is responsible for this effect. Here, we show that naïve CD4(+) T cell homeostatic proliferation (HP) is lost during GVHD because of low systemic IL-7 and impaired dendritic cell (DC) regeneration. We assessed factors involved in DC differentiation and found that although fms-like tyrosine kinase 3 ligand (Flt3-L) levels were normal, stromal-derived factor-1? (SDF-1?) was diminished in the blood of GVHD mice. Unlike Flt3-L treatment, the administration of SDF-1? specifically increased CD8?(+) DC numbers and did not worsen GVHD. Importantly, CD4(+) T cell HP was enhanced only when IL-7 and SDF-1? or Flt3L were coadministered, confirming the crucial role of DCs and IL-7 in restoring CD4(+) T cell regeneration during GVHD. Altogether, our results indicate that CD8?(+) DCs are part of the peripheral niche that controls CD4(+) T cell HP and that their depletion, combined with low systemic IL-7, explains how GVHD constrains naïve CD4(+) T cell reconstitution after allo-SCT. PMID:26151303

  17. Preferential effects of leptin on CD4 T cells in central and peripheral immune system are critically linked to the expression of leptin receptor

    SciTech Connect

    Kim, So Yong; Lim, Ju Hyun; Choi, Sung Won; Kim, Miyoung; Kim, Seong-Tae; Kim, Min-Seon; Cho, You Sook; Chun, Eunyoung; Lee, Ki-Young

    2010-04-09

    Leptin can enhance thymopoiesis and modulate the T-cell immune response. However, it remains controversial whether these effects correlate with the expression of leptin receptor, ObR. We herein addressed this issue by using in vivo animal models and in vitro culture systems. Leptin treatment in both ob/ob mice and normal young mice induced increases of CD4 SP thymocytes in thymus and CD4 T cells in the periphery. Interestingly, expression of the long form ObR was significantly restricted to DN, DP and CD4 SP, but not CD8 SP thymocytes. Moreover, in the reaggregated DP thymocyte cultures with leptin plus TSCs, leptin profoundly induced differentiation of CD4 SP but not CD8 SP thymocytes, suggesting that the effects of leptin on thymocyte differentiation might be closely related to the expression of leptin receptor in developing thymocytes. Surprisingly, ObR expression was markedly higher in peripheral CD4 T cells than that in CD8 T cells. Furthermore, leptin treatment with or without IL-2 and PHA had preferential effects on cell proliferation of CD4 T cells compared to that of CD8 T cells. Collectively, these data provide evidence that the effects of leptin on differentiation and proliferation of CD4 T cells might be closely related to the expression of leptin receptor.

  18. Adolescent brain development in normality and psychopathology

    PubMed Central

    LUCIANA, MONICA

    2014-01-01

    Since this journal’s inception, the field of adolescent brain development has flourished, as researchers have investigated the underpinnings of adolescent risk-taking behaviors. Explanations based on translational models initially attributed such behaviors to executive control deficiencies and poor frontal lobe function. This conclusion was bolstered by evidence that the prefrontal cortex and its interconnections are among the last brain regions to structurally and functionally mature. As substantial heterogeneity of prefrontal function was revealed, applications of neuroeconomic theory to adolescent development led to dual systems models of behavior. Current epidemiological trends, behavioral observations, and functional magnetic resonance imaging based brain activity patterns suggest a quadratic increase in limbically mediated incentive motivation from childhood to adolescence and a decline thereafter. This elevation occurs in the context of immature prefrontal function, so motivational strivings may be difficult to regulate. Theoretical models explain this patterning through brain-based accounts of subcortical–cortical integration, puberty-based models of adolescent sensation seeking, and neurochemical dynamics. Empirically sound tests of these mechanisms, as well as investigations of biology–context interactions, represent the field’s most challenging future goals, so that applications to psychopathology can be refined and so that developmental cascades that incorporate neurobiological variables can be modeled. PMID:24342843

  19. The focal adhesion kinase inhibitor PF-562,271 impairs primary CD4+ T cell activation

    PubMed Central

    Wiemer, Andrew J.; Wernimont, Sarah A.; Cung, Thai-duong; Bennin, David A.; Beggs, Hilary E.; Huttenlocher, Anna

    2013-01-01

    The focal adhesion kinase inhibitor, PF-562,271, is currently in clinical development for cancer, however it is not known how PF-562,271 affects T cell function. Here, we demonstrate inhibitory effects of PF-562,271 on the activation of primary human and mouse T cells. PF-562,271 inhibits T cell receptor signaling-induced T cell adhesion to intercellular adhesion molecule-1 and T cell interactions with antigen-presenting cells. An additional focal adhesion kinase inhibitor, PF-573,228, and genetic depletion of focal adhesion kinase also impair T cell conjugation with antigen-presenting cells. PF-562,271 blocks phosphorylation of the signaling molecules zeta chain associate protein of 70 kDa, linker of activated T cells, and extracellular signal-regulated kinase, and impairs T cell proliferation. The effects observed on T cell proliferation cannot solely be attributed to focal adhesion kinase inhibition, as genetic depletion did not alter proliferation. The effect of PF-562,271 on T cell proliferation is not rescued when proximal T cell receptor signaling is bypassed by stimulation with phorbol-12-myristate-13-acetate and ionomycin. Taken together, our findings demonstrate that focal adhesion kinase regulates integrin-mediated T cell adhesion following T cell receptor activation. Moreover, our findings suggest that PF-562,271 may have immunomodulatory effects that could impact its therapeutic applications. PMID:23928188

  20. The focal adhesion kinase inhibitor PF-562,271 impairs primary CD4+ T cell activation.

    PubMed

    Wiemer, Andrew J; Wernimont, Sarah A; Cung, Thai-Duong; Bennin, David A; Beggs, Hilary E; Huttenlocher, Anna

    2013-09-15

    The focal adhesion kinase inhibitor, PF-562,271, is currently in clinical development for cancer, however it is not known how PF-562,271 affects T cell function. Here, we demonstrate inhibitory effects of PF-562,271 on the activation of primary human and mouse T cells. PF-562,271 inhibits T cell receptor signaling-induced T cell adhesion to intercellular adhesion molecule-1 and T cell interactions with antigen-presenting cells. An additional focal adhesion kinase inhibitor, PF-573,228, and genetic depletion of focal adhesion kinase also impair T cell conjugation with antigen-presenting cells. PF-562,271 blocks phosphorylation of the signaling molecules zeta chain associate protein of 70 kDa, linker of activated T cells, and extracellular signal-regulated kinase, and impairs T cell proliferation. The effects observed on T cell proliferation cannot solely be attributed to focal adhesion kinase inhibition, as genetic depletion did not alter proliferation. The effect of PF-562,271 on T cell proliferation is not rescued when proximal T cell receptor signaling is bypassed by stimulation with phorbol-12-myristate-13-acetate and ionomycin. Taken together, our findings demonstrate that focal adhesion kinase regulates integrin-mediated T cell adhesion following T cell receptor activation. Moreover, our findings suggest that PF-562,271 may have immunomodulatory effects that could impact its therapeutic applications. PMID:23928188

  1. Role of IL-16 in CD4+ T cell-mediated regulation of relapsing multiple sclerosis.

    PubMed

    Skundric, Dusanka S; Cruikshank, William W; Drulovic, Jelena

    2015-01-01

    In an important article published in Nature Medicine, Liu and colleagues described a novel CD4(+) FoxA1(+) regulatory T (Treg) cell population as distinct regulators of relapsing-remitting multiple sclerosis (RRMS) and experimental autoimmune encephalomyelitis (EAE). CD4(+) FoxA1(+) Treg cells appear as key regulators of responsiveness to therapy with interferon beta (IFN-?) in RRMS patients. Data indicate that CD4(+)FoxA1(+) FOXP3(-) Treg cells develop within the central nervous system (CNS), and a potential of cerebellar granule neurons (CGN) in generation of CD4(+)FoxA1(+)PD-L1(hi)FOXP3(-) Treg cells from encephalitogenic CD4(+) T cells. A CD4 co-receptor specific ligand, IL-16, governs trafficking and biological properties of CD4(+) T cells irrespective of their activation state. Functions of IL-16, relevant to Treg cells, include expansion of CD4(+)CD25(+) T cells in long-term cultures with IL-2, de novo induction of FOXP-3 and migration of FOXP-3(+) T cells. IL-16 is highly conserved across species including human and mouse. CGN and neurons in hippocampus contain neuronal-IL-16 (NIL-16), splice variant of immune IL-16, and express CD4 molecule. In a CD4-dependent manner, IL-16 supports cultured CGN survival. Concomitant studies of RRMS lesions and corresponding MOG35-55-induced relapsing EAE in (B6 × JL)F1 (H-2(b/s)) mice discovered similar roles of IL-16 in regulation of relapsing disease. In RRMS and EAE relapse, peak levels of IL-16 and active caspase-3 correlated with CD4(+) T cell infiltration and levels of T-bet, Stat-1(Tyr(701)), and phosphorylated neurofilaments of axonal cytoskeleton [NF (M + H) P], suggesting a role of locally produced IL-16 in regulation of CD4(+) Th1 inflammation and axonal damage, respectively. IL-16 was abundantly present in CD4(+) T cells, followed by CD20(+) B, CD8(+) T, CD83(+) dendritic cells, and Mac-1(+) microglia. Apart from lesions, bioactive IL-16 was located in normal-appearing white matter (NAWM) and normal-appearing grey matter (NAGM) in RRMS brain and spinal cord. A cytokine IL-16 emerges as an important regulator of relapsing MS and EAE. Better understanding of immune cell-neuron interactions mediated by IL-16 will foster development of more specific CD4(+) T cell subset-targeted therapies to prevent or ameliorate progression of neuroinflammation and axonal and neuronal damage. Translational studies necessitate corresponding EAE models. PMID:25896927

  2. Antileukemia multifunctionality of CD4(+) T cells genetically engineered by HLA class I-restricted and WT1-specific T-cell receptor gene transfer.

    PubMed

    Fujiwara, H; Ochi, T; Ochi, F; Miyazaki, Y; Asai, H; Narita, M; Okamoto, S; Mineno, J; Kuzushima, K; Shiku, H; Yasukawa, M

    2015-12-01

    To develop gene-modified T-cell-based antileukemia adoptive immunotherapy, concomitant administration of CD4(+) and CD8(+) T cells that have been gene modified using identical HLA class I-restricted leukemia antigen-specific T-cell receptor (TCR) gene transfer has not yet been fully investigated. Here, using CD4(+) and CD8(+) T cells that had been gene modified with a retroviral vector expressing HLA-A*24:02-restricted and Wilms' tumor 1 (WT1)-specific TCR-?/? genes and siRNAs for endogenous TCRs (WT1-siTCR/CD4(+) T cells and WT1-siTCR/CD8(+) T cells), we examined the utility of this strategy. WT1-siTCR/CD4(+) T cells sufficiently recognized leukemia cells in an HLA class I-restricted manner and provided target-specific Th1 help for WT1-siTCR/CD8(+) T cells. By using a xenografted mouse model, we found that WT1-siTCR/CD4(+) T cells migrated to leukemia sites and subsequently attracted WT1-siTCR/CD8(+) T cells via chemotaxis. Therapy-oriented experiments revealed effective enhancement of leukemia suppression mediated by concomitant administration of WT1-siTCR/CD4(+) T cells and WT1-siTCR/CD8(+) T cells. Importantly, this augmented efficacy in the presence of WT1-siTCR/CD4(+) T cells was correlated with longer survival and enhanced formation of memory T cells by WT1-siTCR/CD8(+) T cells. Collectively, our experimental findings strongly suggest that this strategy would be clinically advantageous for the treatment of human leukemia. PMID:26104661

  3. ?? T Cell Subsets: A Link Between TCR and Function?

    PubMed Central

    O’Brien, Rebecca L.; Born, Willi K.

    2010-01-01

    The ?? T lmphocytes are often divided into subsets based upon expression of certain TCR components. This division was initially made because ?? T cells residing in particular epithelia were found to show tissue specific differences in their TCRs. Many examples now show that ?? T cell subsets also appear to be biased to carry out particular functions. This suggests that particular ?? TCR types direct the cells to acquire a certain type of functional programming during thymic development. Here, we describe functionally distinct, TCR-defined ?? T cell subsets, and evidence that their functions are pre-determined in the thymus. PMID:20451408

  4. Comparison of T cell receptor alpha, beta, and gamma gene rearrangement and expression in T cell acute lymphoblastic leukemia.

    E-print Network

    Hara, Junichi; Benedict, Stephen H.; Champagne, Eric; Mak, Tak W.; Minden, Mark; Gelfand, Erwin W.

    1988-04-01

    We have analyzed the configuration of the T cell receptor (TCR) alpha gene using newly developed genomic joining region (J alpha) probes, which cover approximately 80 kb of the J alpha region upstream from the constant region in 19 patients...

  5. Evaluating effects of tyrosine phosphatase inhibitors on T cell receptor signaling.

    PubMed

    Rahmouni, Souad; Delacroix, Laurence; Liu, Wallace H; Tautz, Lutz

    2013-01-01

    The importance of tyrosine phosphorylation in normal cell physiology is well established, highlighted by the many human diseases that stem from abnormalities in protein tyrosine kinase (PTK) and protein tyrosine phosphatase (PTP) function. Contrary to earlier assumptions, it is now clear that both PTKs and PTPs are highly specific, non-redundant, and tightly regulated enzymes. Hematopoietic cells express particularly high numbers of PTKs and PTPs, and aberrant function of these proteins have been linked to many hematopoietic disorders. While PTK inhibitors are among FDA approved drugs for the treatment of leukemia and other cancers, efforts to develop therapeutics that target specific PTPs are still in its infancy. Here, we describe methods on how to evaluate effects of PTP inhibitors on T cell receptor signaling. Moreover, we provide a comprehensive strategy for compound prioritization, applicable to any drug discovery project involving T cells. We present a testing funnel that starts with relatively high-throughput luciferase reporter assays, followed by immunoblot, calcium flux, flow cytometry, and proliferation assays, continues with cytokine bead arrays, and finishes with specificity assays that involve RNA interference. We provide protocols for experiments in the Jurkat T cell line, but more importantly give detailed instructions, paired with numerous tips, on how to prepare and work with primary human T cells. PMID:23860658

  6. Antigen-induced human T cell help. Precursor frequency, radiation sensitivity, and allogeneic effects

    SciTech Connect

    Lane, H.C.; Whalen, G.; Fauci, A.S.

    1983-08-01

    We have recently noted marked differences between the in vitro responses of human B lymphocytes to stimulation with soluble antigens vs. stimulation with mitogens. In the present study, these differences were analyzed in terms of the precursor frequencies for the T cells and B cells involved and in terms of the radiation sensitivity of the T cells providing help in the two systems. Marked differences were found between antigen-induced and mitogen-induced systems with regard to T cell precursor frequencies and radiation sensitivity. In contrast, the precursor frequencies for the B cells involved in the two systems were approximately the same. In addition, having developed a system for the study of human antigen-specific B cell responses, we were interested in delineating the nature of the allogeneic effects that might be operative in this system. Marked allogeneic effects, both positive and negative, were noted in this system and will need to be taken into account in any studies that try to address the question of the genetic restriction, if any, that exists in human antigen-specific T cell-B cell collaboration. Appreciation of the marked differences between the antigen-specific and mitogen-induced activation and immunoregulation of human B cell responses will be of importance in understanding the relationship between specificity and nonspecificity of antibody production in normal and disease states.

  7. Integrated molecular analysis of adult T cell leukemia/lymphoma.

    PubMed

    Kataoka, Keisuke; Nagata, Yasunobu; Kitanaka, Akira; Shiraishi, Yuichi; Shimamura, Teppei; Yasunaga, Jun-Ichirou; Totoki, Yasushi; Chiba, Kenichi; Sato-Otsubo, Aiko; Nagae, Genta; Ishii, Ryohei; Muto, Satsuki; Kotani, Shinichi; Watatani, Yosaku; Takeda, June; Sanada, Masashi; Tanaka, Hiroko; Suzuki, Hiromichi; Sato, Yusuke; Shiozawa, Yusuke; Yoshizato, Tetsuichi; Yoshida, Kenichi; Makishima, Hideki; Iwanaga, Masako; Ma, Guangyong; Nosaka, Kisato; Hishizawa, Masakatsu; Itonaga, Hidehiro; Imaizumi, Yoshitaka; Munakata, Wataru; Ogasawara, Hideaki; Sato, Toshitaka; Sasai, Ken; Muramoto, Kenzo; Penova, Marina; Kawaguchi, Takahisa; Nakamura, Hiromi; Hama, Natsuko; Shide, Kotaro; Kubuki, Yoko; Hidaka, Tomonori; Kameda, Takuro; Nakamaki, Tsuyoshi; Ishiyama, Ken; Miyawaki, Shuichi; Yoon, Sung-Soo; Tobinai, Kensei; Miyazaki, Yasushi; Takaori-Kondo, Akifumi; Matsuda, Fumihiko; Takeuchi, Kengo; Nureki, Osamu; Aburatani, Hiroyuki; Watanabe, Toshiki; Shibata, Tatsuhiro; Matsuoka, Masao; Miyano, Satoru; Shimoda, Kazuya; Ogawa, Seishi

    2015-11-01

    Adult T cell leukemia/lymphoma (ATL) is a peripheral T cell neoplasm of largely unknown genetic basis, associated with human T cell leukemia virus type-1 (HTLV-1) infection. Here we describe an integrated molecular study in which we performed whole-genome, exome, transcriptome and targeted resequencing, as well as array-based copy number and methylation analyses, in a total of 426 ATL cases. The identified alterations overlap significantly with the HTLV-1 Tax interactome and are highly enriched for T cell receptor-NF-?B signaling, T cell trafficking and other T cell-related pathways as well as immunosurveillance. Other notable features include a predominance of activating mutations (in PLCG1, PRKCB, CARD11, VAV1, IRF4, FYN, CCR4 and CCR7) and gene fusions (CTLA4-CD28 and ICOS-CD28). We also discovered frequent intragenic deletions involving IKZF2, CARD11 and TP73 and mutations in GATA3, HNRNPA2B1, GPR183, CSNK2A1, CSNK2B and CSNK1A1. Our findings not only provide unique insights into key molecules in T cell signaling but will also guide the development of new diagnostics and therapeutics in this intractable tumor. PMID:26437031

  8. T cells in multiple sclerosis and experimental autoimmune encephalomyelitis.

    PubMed

    Fletcher, J M; Lalor, S J; Sweeney, C M; Tubridy, N; Mills, K H G

    2010-10-01

    Multiple sclerosis (MS) is a demyelinating inflammatory disorder of the central nervous system (CNS), which involves autoimmune responses to myelin antigens. Studies in experimental autoimmune encephalomyelitis (EAE), an animal model for MS, have provided convincing evidence that T cells specific for self-antigens mediate pathology in these diseases. Until recently, T helper type 1 (Th1) cells were thought to be the main effector T cells responsible for the autoimmune inflammation. However more recent studies have highlighted an important pathogenic role for CD4(+) T cells that secrete interleukin (IL)-17, termed Th17, but also IL-17-secreting ?? T cells in EAE as well as other autoimmune and chronic inflammatory conditions. This has prompted intensive study of the induction, function and regulation of IL-17-producing T cells in MS and EAE. In this paper, we review the contribution of Th1, Th17, ??, CD8(+) and regulatory T cells as well as the possible development of new therapeutic approaches for MS based on manipulating these T cell subtypes. PMID:20682002

  9. On the ontogeny and physiology of regulatory T cells.

    PubMed

    Annacker, O; Pimenta-Araujo, R; Burlen-Defranoux, O; Bandeira, A

    2001-08-01

    Lymphocytes can interfere with the activity of other lymphocytes in a thousand and one ways. A particular subset of so-called regulatory CD4+ T cells is capable of controlling the activity of other lymphocytes in yet another way. Their function is primarily defined by the ability to protect the integrity of tissues and organs in vivo. This was demonstrated in experimental models of natural tolerance to peripheral tissues, transplantation tolerance and the regulation of immune responses promoted by exogenous antigens at the level of the intestinal mucosa. Moreover, regulatory T cells also play a major role in the systemic homeostatic mechanisms that control total lymphocyte numbers. There is good evidence to support the contention that a significant fraction of the naturally occurring regulatory T cells is generated in the thymus following selection mediated by high avidity T-cell receptor/ligand interactions. Symbolically, self-reactive regulatory T cells do represent the breakthrough of concepts challenging the long-lasting Burnetian dogma that all autoreactive cells should be eliminated or inactivated. Although clonal deletion of self-reactive cells is a fundamental process in T-cell development, controlled autoreactivity is part of the physiology of the immune system. Thus, autoreactive regulatory T cells also protect immunologists from the desperate hunting for the evil of horror autotoxicus. PMID:11722620

  10. Identification of novel CD8+ T cell epitopes in human herpesvirus 6B U11 and U90

    PubMed Central

    Halawi, Mustafa; Khan, Naeem; Blake, Neil

    2015-01-01

    Human herpesvirus 6B (HHV6B) infects over 90% of the population, and normally establishes a latent infection, where episodes of reactivation are asymptomatic. However, in immunocompromised patients HHV6B reactivation is associated with high morbidity and mortality. Cellular immunotherapy has been utilised against other herpesvirus in immunocompromised settings. However, limited information on the immune response against HHV6B has hampered the development of immunotherapy for HHV6B-driven disease. In this study, we have analysed the cellular immune response against four HHV6B antigens in a panel of 30 healthy donors. We show that the base-line level of T cell reactivity in peripheral blood is very low to undetectable. A short-term reactivation step enabled expansion of T cell responses, and all donors responded to at least 1 antigen, but more commonly 3 or 4. A hierarchy of immunogenicity was determined with antigens U90 and U54 being co-dominant, followed by U11 and U39. Putative CD8+ T cell epitopes were mapped to U90 and U11, predicted to be presented in the context of HLA-A1, A29, B39 and C6. T cells reactive against these novel epitopes were able to recognise virus-infected cells. Our data is supportive of the application and on-going development of T cell immunotherapy against HHVB-driven disease in the immunocompromised host. PMID:26029371

  11. Macrophage and T Cell Produced IL-10 Promotes Viral Chronicity

    PubMed Central

    Richter, Kirsten; Perriard, Guillaume; Behrendt, Rayk; Schwendener, Reto A.; Sexl, Veronika; Dunn, Robert; Kamanaka, Masahito; Flavell, Richard A.; Roers, Axel; Oxenius, Annette

    2013-01-01

    Chronic viral infections lead to CD8+ T cell exhaustion, characterized by impaired cytokine secretion. Presence of the immune-regulatory cytokine IL-10 promotes chronicity of Lymphocytic Choriomeningitis Virus (LCMV) Clone 13 infection, while absence of IL-10/IL-10R signaling early during infection results in viral clearance and higher percentages and numbers of antiviral, cytokine producing T cells. IL-10 is produced by several cell types during LCMV infection but it is currently unclear which cellular sources are responsible for induction of viral chronicity. Here, we demonstrate that although dendritic cells produce IL-10 and overall IL-10 mRNA levels decrease significantly in absence of CD11c+ cells, absence of IL-10 produced by CD11c+ cells failed to improve the LCMV-specific T cell response and control of LCMV infection. Similarly, NK cell specific IL-10 deficiency had no positive impact on the LCMV-specific T cell response or viral control, even though high percentages of NK cells produced IL-10 at early time points after infection. Interestingly, we found markedly improved T cell responses and clearance of normally chronic LCMV Clone 13 infection when either myeloid cells or T cells lacked IL-10 production and mice depleted of monocytes/macrophages or CD4+ T cells exhibited reduced overall levels of IL-10 mRNA. These data suggest that the decision whether LCMV infection becomes chronic or can be cleared critically depends on early CD4+ T cell and monocyte/macrophage produced IL-10. PMID:24244162

  12. Macrophage and T cell produced IL-10 promotes viral chronicity.

    PubMed

    Richter, Kirsten; Perriard, Guillaume; Behrendt, Rayk; Schwendener, Reto A; Sexl, Veronika; Dunn, Robert; Kamanaka, Masahito; Flavell, Richard A; Roers, Axel; Oxenius, Annette

    2013-01-01

    Chronic viral infections lead to CD8(+) T cell exhaustion, characterized by impaired cytokine secretion. Presence of the immune-regulatory cytokine IL-10 promotes chronicity of Lymphocytic Choriomeningitis Virus (LCMV) Clone 13 infection, while absence of IL-10/IL-10R signaling early during infection results in viral clearance and higher percentages and numbers of antiviral, cytokine producing T cells. IL-10 is produced by several cell types during LCMV infection but it is currently unclear which cellular sources are responsible for induction of viral chronicity. Here, we demonstrate that although dendritic cells produce IL-10 and overall IL-10 mRNA levels decrease significantly in absence of CD11c(+) cells, absence of IL-10 produced by CD11c(+) cells failed to improve the LCMV-specific T cell response and control of LCMV infection. Similarly, NK cell specific IL-10 deficiency had no positive impact on the LCMV-specific T cell response or viral control, even though high percentages of NK cells produced IL-10 at early time points after infection. Interestingly, we found markedly improved T cell responses and clearance of normally chronic LCMV Clone 13 infection when either myeloid cells or T cells lacked IL-10 production and mice depleted of monocytes/macrophages or CD4(+) T cells exhibited reduced overall levels of IL-10 mRNA. These data suggest that the decision whether LCMV infection becomes chronic or can be cleared critically depends on early CD4(+) T cell and monocyte/macrophage produced IL-10. PMID:24244162

  13. ZEB2 drives immature T-cell lymphoblastic leukaemia development via enhanced tumour-initiating potential and IL-7 receptor signalling

    PubMed Central

    Goossens, Steven; Radaelli, Enrico; Blanchet, Odile; Durinck, Kaat; Van der Meulen, Joni; Peirs, Sofie; Taghon, Tom; Tremblay, Cedric S.; Costa, Magdaline; Ghahremani, Morvarid Farhang; De Medts, Jelle; Bartunkova, Sonia; Haigh, Katharina; Schwab, Claire; Farla, Natalie; Pieters, Tim; Matthijssens, Filip; Van Roy, Nadine; Best, J. Adam; Deswarte, Kim; Bogaert, Pieter; Carmichael, Catherine; Rickard, Adam; Suryani, Santi; Bracken, Lauryn S.; Alserihi, Raed; Canté-Barrett, Kirsten; Haenebalcke, Lieven; Clappier, Emmanuelle; Rondou, Pieter; Slowicka, Karolina; Huylebroeck, Danny; Goldrath, Ananda W.; Janzen, Viktor; McCormack, Matthew P.; Lock, Richard B.; Curtis, David J.; Harrison, Christine; Berx, Geert; Speleman, Frank; Meijerink, Jules P. P.; Soulier, Jean; Van Vlierberghe, Pieter; Haigh, Jody J.

    2015-01-01

    Early T-cell precursor leukaemia (ETP-ALL) is a high-risk subtype of human leukaemia that is poorly understood at the molecular level. Here we report translocations targeting the zinc finger E-box-binding transcription factor ZEB2 as a recurrent genetic lesion in immature/ETP-ALL. Using a conditional gain-of-function mouse model, we demonstrate that sustained Zeb2 expression initiates T-cell leukaemia. Moreover, Zeb2-driven mouse leukaemia exhibit some features of the human immature/ETP-ALL gene expression signature, as well as an enhanced leukaemia-initiation potential and activated Janus kinase (JAK)/signal transducers and activators of transcription (STAT) signalling through transcriptional activation of IL7R. This study reveals ZEB2 as an oncogene in the biology of immature/ETP-ALL and paves the way towards pre-clinical studies of novel compounds for the treatment of this aggressive subtype of human T-ALL using our Zeb2-driven mouse model. PMID:25565005

  14. T-cell reconstitution after allogeneic stem cell transplantation: assessment by measurement of the sjTREC/?TREC ratio and thymic naive T cells.

    PubMed

    Ringhoffer, Simone; Rojewski, Markus; Döhner, Hartmut; Bunjes, Donald; Ringhoffer, Mark

    2013-10-01

    The immune reconstitution after allogeneic hematopoietic stem cell transplantation comprises thymus-dependent and thymus-independent pathways. We wanted to improve the understanding of this complex process using two different measurements at definite checkpoints of T-cell neogenesis. We therefore assessed the thymus-dependent pathway by combining measurements of single joint T-cell receptor excision circles (sjTREC) and ? T-cell receptor excision circles (?TREC) in an improved quantitative light-cycler hybridization polymerase chain reaction assay. In a subgroup of patients, we additionally assessed the proliferation kinetics of the CD31(+) thymic naïve cell population, which corresponds to recent thymic emigrants by six-color immunostaining. After the establishment of normal values in 22 healthy volunteers, we applied our polymerase chain reaction to 66 patients undergoing allogeneic hematopoietic stem cell transplantation at a median age of 44 years. It took more than 2 years after transplant to restore the pre-transplant thymic proliferation capacity. Only one third of the patients in our longitudinal study reached age-adjusted normal values for both sjTREC and ?TREC at a median follow-up of 558 days, with acute graft-versus-host disease being the most prominent negative factor by univariate analysis. We observed several patterns of sjTREC and ?TREC recovery suggesting different mechanisms of thymic damage in individual patients. In a comparison of CD31(+) thymic naïve cells between volunteers and patients after transplant we found a significantly higher peak proliferation rate within the latter population in the first year after transplantation. The combination of measurements of sjTREC and ?TREC by our simplified polymerase chain reaction assay provides insight about the stage of T-cell development affected by different types of damage and may help to choose the correct therapeutic intervention. Besides the sole thymic T-cell neogenesis, proliferation within the CD31(+) thymic naïve cell compartment contributed to the replenishment of the naïve T-cell pool after transplantation. PMID:23585532

  15. T-cell reconstitution after allogeneic stem cell transplantation: assessment by measurement of the sjTREC/?TREC ratio and thymic naïve T cells

    PubMed Central

    Ringhoffer, Simone; Rojewski, Markus; Döhner, Hartmut; Bunjes, Donald; Ringhoffer, Mark

    2013-01-01

    The immune reconstitution after allogeneic hematopoietic stem cell transplantation comprises thymus-dependent and thymus-independent pathways. We wanted to improve the understanding of this complex process using two different measurements at definite checkpoints of T-cell neogenesis. We therefore assessed the thymus-dependent pathway by combining measurements of single joint T-cell receptor excision circles (sjTREC) and ? T-cell receptor excision circles (?TREC) in an improved quantitative light-cycler hybridization polymerase chain reaction assay. In a subgroup of patients, we additionally assessed the proliferation kinetics of the CD31+ thymic naïve cell population, which corresponds to recent thymic emigrants by six-color immunostaining. After the establishment of normal values in 22 healthy volunteers, we applied our polymerase chain reaction to 66 patients undergoing allogeneic hematopoietic stem cell transplantation at a median age of 44 years. It took more than 2 years after transplant to restore the pre-transplant thymic proliferation capacity. Only one third of the patients in our longitudinal study reached age-adjusted normal values for both sjTREC and ?TREC at a median follow-up of 558 days, with acute graft-versus-host disease being the most prominent negative factor by univariate analysis. We observed several patterns of sjTREC and ?TREC recovery suggesting different mechanisms of thymic damage in individual patients. In a comparison of CD31+ thymic naïve cells between volunteers and patients after transplant we found a significantly higher peak proliferation rate within the latter population in the first year after transplantation. The combination of measurements of sjTREC and ?TREC by our simplified polymerase chain reaction assay provides insight about the stage of T-cell development affected by different types of damage and may help to choose the correct therapeutic intervention. Besides the sole thymic T-cell neogenesis, proliferation within the CD31+ thymic naïve cell compartment contributed to the replenishment of the naïve T-cell pool after transplantation. PMID:23585532

  16. Developing Visualization Support System for Teaching/Learning Database Normalization

    ERIC Educational Resources Information Center

    Folorunso, Olusegun; Akinwale, AdioTaofeek

    2010-01-01

    Purpose: In tertiary institution, some students find it hard to learn database design theory, in particular, database normalization. The purpose of this paper is to develop a visualization tool to give students an interactive hands-on experience in database normalization process. Design/methodology/approach: The model-view-controller architecture…

  17. Control of Murine Cytomegalovirus Infection by ?? T Cells

    PubMed Central

    Sell, Sabrina; Dietz, Monika; Schneider, Andrea; Holtappels, Rafaela; Mach, Michael; Winkler, Thomas H.

    2015-01-01

    Infections with cytomegalovirus (CMV) can cause severe disease in immunosuppressed patients and infected newborns. Innate as well as cellular and humoral adaptive immune effector functions contribute to the control of CMV in immunocompetent individuals. None of the innate or adaptive immune functions are essential for virus control, however. Expansion of ?? T cells has been observed during human CMV (HCMV) infection in the fetus and in transplant patients with HCMV reactivation but the protective function of ?? T cells under these conditions remains unclear. Here we show for murine CMV (MCMV) infections that mice that lack CD8 and CD4 ??-T cells as well as B lymphocytes can control a MCMV infection that is lethal in RAG-1-/- mice lacking any T- and B-cells. ?? T cells, isolated from infected mice can kill MCMV infected target cells in vitro and, importantly, provide long-term protection in infected RAG-1-/- mice after adoptive transfer. ?? T cells in MCMV infected hosts undergo a prominent and long-lasting phenotypic change most compatible with the view that the majority of the ?? T cell population persists in an effector/memory state even after resolution of the acute phase of the infection. A clonotypically focused V?1 and V?2 repertoire was observed at later stages of the infection in the organs where MCMV persists. These findings add ?? T cells as yet another protective component to the anti-CMV immune response. Our data provide clear evidence that ?? T cells can provide an effective control mechanism of acute CMV infections, particularly when conventional adaptive immune mechanisms are insufficient or absent, like in transplant patient or in the developing immune system in utero. The findings have implications in the stem cell transplant setting, as antigen recognition by ?? T cells is not MHC-restricted and dual reactivity against CMV and tumors has been described. PMID:25658831

  18. High PD-1 expression and suppressed cytokine signaling distinguish T cells infiltrating follicular lymphoma tumors from peripheral T cells

    PubMed Central

    Myklebust, June H.; Irish, Jonathan M.; Brody, Joshua; Czerwinski, Debra K.; Houot, Roch; Kohrt, Holbrook E.; Timmerman, John; Said, Jonathan; Green, Michael R.; Delabie, Jan; Kolstad, Arne; Alizadeh, Ash A.

    2013-01-01

    Defects in T-cell function in patients with cancer might influence their capacity to mount efficient antitumor immune responses. Here, we identified highly reduced IL-4–, IL-10–, and IL-21–induced phosphorylation of STAT6 and STAT3 in tumor-infiltrating T cells (TILs) in follicular lymphoma (FL) tumors, contrasting other non-Hodgkin lymphoma TILs. By combining phospho-protein–specific flow cytometry with several T-cell markers, we identified that CD4+CD45RO+CD62L? FL TILs were largely nonresponsive to cytokines, in contrast to the corresponding autologous peripheral blood subset. We observed differential expression of the inhibitory receptor PD-1 in FL TILs and peripheral blood T cells. Furthermore, CD4+PD-1hi FL TILs, containing TFH and non-TFH cells, had lost their cytokine responsiveness, whereas PD-1? TILs had normal cytokine signaling. However, this phenomenon was not tumor specific, because tonsil T cells were similar to FL TILs. FL tumor cells were negative for PD-1 ligands, but PD-L1+ histiocytes were found within the T cell–rich zone of the neoplastic follicles. Disruption of the microenvironment and in vitro culture of FL TILs could restore cytokine signaling in the PD-1hi subset. Because FL TILs in vivo probably receive suppressive signals through PD-1, this provides a rationale for testing PD-1 Ab in combination with immunotherapy in patients with FL. PMID:23297127

  19. Ikaros mediates gene silencing in T cells through Polycomb repressive complex 2

    PubMed Central

    Oravecz, Attila; Apostolov, Apostol; Polak, Katarzyna; Jost, Bernard; Le Gras, Stéphanie; Chan, Susan; Kastner, Philippe

    2015-01-01

    T-cell development is accompanied by epigenetic changes that ensure the silencing of stem cell-related genes and the activation of lymphocyte-specific programmes. How transcription factors influence these changes remains unclear. We show that the Ikaros transcription factor forms a complex with Polycomb repressive complex 2 (PRC2) in CD4?CD8? thymocytes and allows its binding to more than 500 developmentally regulated loci, including those normally activated in haematopoietic stem cells and others induced by the Notch pathway. Loss of Ikaros in CD4?CD8? cells leads to reduced histone H3 lysine 27 trimethylation and ectopic gene expression. Furthermore, Ikaros binding triggers PRC2 recruitment and Ikaros interacts with PRC2 independently of the nucleosome remodelling and deacetylation complex. Our results identify Ikaros as a fundamental regulator of PRC2 function in developing T cells. PMID:26549758

  20. MicroRNAs and Their Targets Are Differentially Regulated in Adult and Neonatal Mouse CD8+ T Cells.

    PubMed

    Wissink, Erin M; Smith, Norah L; Spektor, Roman; Rudd, Brian D; Grimson, Andrew

    2015-11-01

    Immunological memory, which protects organisms from re-infection, is a hallmark of the mammalian adaptive immune system and the underlying principle of vaccination. In early life, however, mice and other mammals are deficient at generating memory CD8+ T cells, which protect organisms from intracellular pathogens. The molecular basis that differentiates adult and neonatal CD8+ T cells is unknown. MicroRNAs (miRNAs) are both developmentally regulated and required for normal adult CD8+ T cell functions. We used next-generation sequencing to identify mouse miRNAs that are differentially regulated in adult and neonatal CD8+ T cells, which may contribute to the impaired development of neonatal memory cells. The miRNA profiles of adult and neonatal cells were surprisingly similar during infection; however, we observed large differences prior to infection. In particular, miR-29 and miR-130 have significant differential expression between adult and neonatal cells before infection. Importantly, using RNA-Seq, we detected reciprocal changes in expression of messenger RNA targets for both miR-29 and miR-130. Moreover, targets that we validated include Eomes and Tbx21, key genes that regulate the formation of memory CD8+ T cells. Notably, age-dependent changes in miR-29 and miR-130 are conserved in human CD8+ T cells, further suggesting that these developmental differences are biologically relevant. Together, these results demonstrate that miR-29 and miR-130 are likely important regulators of memory CD8+ T cell formation and suggest that neonatal cells are committed to a short-lived effector cell fate prior to infection. PMID:26416483

  1. A Canonical V?4V?4+ ?? T Cell Population with Distinct Stimulation Requirements which Promotes the Th17 Response

    PubMed Central

    Roark, Christina L.; Huang, Yafei; Jin, Niyun; Aydintug, M. Kemal; Casper, Tamara; Sun, Deming; Born, Willi K.; O’Brien, Rebecca L.

    2012-01-01

    We previously reported a subset of ?? T cells in mice which preferentially responds following intradermal immunization with collagen in Complete Freund’s Adjuvant (CFA). These cells express a nearly invariant “canonical” V?4V?4+ TCR. They are potent producers of IL-17A, and promote the development of collagen-induced arthritis. In this study, we report that CFA emulsified with PBS alone (without collagen) is sufficient to induce a strong response of V?4V?4+ cells in the draining lymph nodes of DBA/1 and C57BL/6 mice, and that the TCRs of the elicited V?4V?4+ cells in both strains heavily favor the canonical sequence. However, although both CFA and Incomplete Freund’s Adjuvant (IFA, which lacks the killed mycobacteria present in CFA) induced V?4V?4+ ?? T cell to expand, only CFA stimulated them to express IL-17A. The route of immunization was also critical, since intraperitoneal CFA induced only a weak response by these cells, whereas intradermal or subcutaneous CFA strongly stimulated them, suggesting that the canonical CFA-elicited V?4V?4+ cells are recruited from V?4+ ?? T cells normally found in the dermis. Their IL-17A response requires the toll-like receptor adapter protein MyD88, and their activation is enhanced by IFN?, although ?? T cells need not be present. The CFA-elicited V?4V?4+ ?? T cells show a cytokine profile different from that of other previously described IL-17-producing ?? T cells. Finally, the V?4V?4+ subset appears to promote the Th17 ?? T cell response, suggesting its importance in mounting an effective immune response against certain pathogens. PMID:22961659

  2. An Enhancer of the IL-7 Receptor ?-Chain Locus Controls IL-7 Receptor Expression and Maintenance of Peripheral T Cells.

    PubMed

    Abe, Akifumi; Tani-ichi, Shizue; Shitara, Soichiro; Cui, Guangwei; Yamada, Hisataka; Miyachi, Hitoshi; Kitano, Satsuki; Hara, Takahiro; Abe, Ryo; Yoshikai, Yasunobu; Ikuta, Koichi

    2015-10-01

    The IL-7R plays critical roles in lymphocyte development and homeostasis. Although IL-7R expression is strictly regulated during lymphocyte differentiation and the immune response, little is known regarding its in vivo regulation. To address this issue, we established a mouse line with targeted deletion of the conserved non-coding sequence 1 (CNS1) element found 3.6 kb upstream of the IL-7R? promoter. We report that IL-7R? is expressed normally on T and B cells in thymus and bone marrow of CNS1(-/-) mice except for in regulatory T cells. In contrast, these mice show reduced IL-7R? expression in conventional CD4 and CD8 T cells as well as regulatory T, NKT, and ?? T cells in the periphery. CD4 T cells of CNS1(-/-) mice showed IL-7R? upregulation in the absence of growth factors and IL-7R? downregulation by IL-7 or TCR stimulation, although the expression levels were lower than those in control mice. Naive CD4 and CD8 T cells of CNS1(-/-) mice show attenuated survival by culture with IL-7 and reduced homeostatic proliferation after transfer into lymphopenic hosts. CNS1(-/-) mice exhibit impaired maintenance of Ag-stimulated T cells. Furthermore, IL-7R? upregulation by glucocorticoids and TNF-? was abrogated in CNS1(-/-) mice. This work demonstrates that the CNS1 element controls IL-7R? expression and maintenance of peripheral T cells, suggesting differential regulation of IL-7R? expression between central and peripheral lymphoid organs. PMID:26336149

  3. MicroRNAs and Their Targets Are Differentially Regulated in Adult and Neonatal Mouse CD8+ T Cells

    PubMed Central

    Wissink, Erin M.; Smith, Norah L.; Spektor, Roman; Rudd, Brian D.; Grimson, Andrew

    2015-01-01

    Immunological memory, which protects organisms from re-infection, is a hallmark of the mammalian adaptive immune system and the underlying principle of vaccination. In early life, however, mice and other mammals are deficient at generating memory CD8+ T cells, which protect organisms from intracellular pathogens. The molecular basis that differentiates adult and neonatal CD8+ T cells is unknown. MicroRNAs (miRNAs) are both developmentally regulated and required for normal adult CD8+ T cell functions. We used next-generation sequencing to identify mouse miRNAs that are differentially regulated in adult and neonatal CD8+ T cells, which may contribute to the impaired development of neonatal memory cells. The miRNA profiles of adult and neonatal cells were surprisingly similar during infection; however, we observed large differences prior to infection. In particular, miR-29 and miR-130 have significant differential expression between adult and neonatal cells before infection. Importantly, using RNA-Seq, we detected reciprocal changes in expression of messenger RNA targets for both miR-29 and miR-130. Moreover, targets that we validated include Eomes and Tbx21, key genes that regulate the formation of memory CD8+ T cells. Notably, age-dependent changes in miR-29 and miR-130 are conserved in human CD8+ T cells, further suggesting that these developmental differences are biologically relevant. Together, these results demonstrate that miR-29 and miR-130 are likely important regulators of memory CD8+ T cell formation and suggest that neonatal cells are committed to a short-lived effector cell fate prior to infection. PMID:26416483

  4. B and CD4+ T cell expression of TLR2 are critical for optimal induction of a T cell-dependent humoral immune response to intact Streptococcus pneumoniae

    PubMed Central

    Vasilevsky, S.; Chattopadhyay, G.; Colino, Jesus; Yeh, T-J; Chen, Q.; Sen, G.; Snapper, C. M.

    2009-01-01

    Summary TLR2?/? mice immunized with Streptococcus pneumoniae (Pn) elicit normal IgM, but defective CD4+ T cell-dependent (TD) type 1 IgG isotype production, associated with a largely intact innate immune response. We studied the TD phosphorylcholine (PC)-specific IgG3 versus the T cell-independent IgM response to Pn to determine whether TLR2 signals directly via the adaptive immune system. Pn-activated TLR2?/? bone marrow dendritic cells (BMDC) have only a modest defect in cytokine secretion, undergo normal maturation, and when transferred into naive WT mice elicit a normal IgM and IgG3 anti-PC response, relative to WT BMDC. Pn synergizes with BCR and TCR signaling for DNA synthesis in purified WT B and CD4+ T cells, respectively, but is defective in cells lacking TLR2. Pn primes TLR2?/? mice for a normal CD4+ T cell IFN-? recall response. Notably, TLR2?/? B cells transferred into RAG-2?/? mice with WT CD4+ T cells, or TLR2?/? CD4+ T cells transferred into athymic nude mice, each elicit a defective IgG3, in contrast to normal IgM, anti-PC response relative to WT cells. These data are the first to demonstrate a major role for B cell and CD4+ T cell expression of TLR2 for eliciting an anti-bacterial humoral immune response. PMID:19003933

  5. TGF-? signalling is required for CD4? T cell homeostasis but dispensable for regulatory T cell function.

    PubMed

    Sledzi?ska, Anna; Hemmers, Saskia; Mair, Florian; Gorka, Oliver; Ruland, Jürgen; Fairbairn, Lynsey; Nissler, Anja; Müller, Werner; Waisman, Ari; Becher, Burkhard; Buch, Thorsten

    2013-10-01

    TGF-? is widely held to be critical for the maintenance and function of regulatory T (T(reg)) cells and thus peripheral tolerance. This is highlighted by constitutive ablation of TGF-? receptor (TR) during thymic development in mice, which leads to a lethal autoimmune syndrome. Here we describe that TGF-?-driven peripheral tolerance is not regulated by TGF-? signalling on mature CD4? T cells. Inducible TR2 ablation specifically on CD4? T cells did not result in a lethal autoinflammation. Transfer of these TR2-deficient CD4? T cells to lymphopenic recipients resulted in colitis, but not overt autoimmunity. In contrast, thymic ablation of TR2 in combination with lymphopenia led to lethal multi-organ inflammation. Interestingly, deletion of TR2 on mature CD4? T cells does not result in the collapse of the T(reg) cell population as observed in constitutive models. Instead, a pronounced enlargement of both regulatory and effector memory T cell pools was observed. This expansion is cell-intrinsic and seems to be caused by increased T cell receptor sensitivity independently of common gamma chain-dependent cytokine signals. The expression of Foxp3 and other regulatory T cells markers was not dependent on TGF-? signalling and the TR2-deficient T(reg) cells retained their suppressive function both in vitro and in vivo. In summary, absence of TGF-? signalling on mature CD4? T cells is not responsible for breakdown of peripheral tolerance, but rather controls homeostasis of mature T cells in adult mice. PMID:24115907

  6. IL-12 induced the generation of IL-21- and IFN-?-co-expressing poly-functional CD4+ T cells from human naive CD4+ T cells.

    PubMed

    Yu, Sifei; Jia, Lei; Zhang, Yannan; Zhong, Junmin; Yang, Binyan; Wu, Changyou

    2015-11-01

    Interleukine-12 is critical for the differentiation of Th1 cells and can improve the development of Th1 cells with Tfh cell features in mouse model. Human effector CD4(+) T cells also exhibit poly-functionality by co-expressing IL-21 and IFN-?. However, the effects of IL-12 on regulating generation of human IL-21- and IFN-?-expressing CD4(+) T cells are still incompletely understood. Our studies found that IL-12 but not IL-21 could induce the differentiation of human naive CD4(+) T cells into multi-cytokine expressing CD4(+) T cells in vitro, which co-expressed IL-21 and IFN-? with or without IL-2 and TNF-?. At early stage of differentiation, addition of excess exogenous IFN-? could increase the generation of IL-21- and IFN-?-expressing CD4(+) T cells, furthermore, anti-IFN-? depressed the percentage of poly-functional CD4(+) T cells. Phenotypically, IL-21(+)IFN-?(+)CD4(+) T cells exhibited more characteristic features about both of Th1 and Tfh cells than IL-21 or IFN-? single-expressing CD4(+) T cells. Mechamistically, IL-12 modulated the differentiation of IL-21(+)IFN-?(+)CD4(+) T cells from naive CD4(+) T cells via the pathways of STAT-1/4, T-bet and BCL(-)6. Different from naive CD4(+) T cells, IL-12 increasing the generation of IL-21(+)IFN-?(+)CD4(+) T cells from memory CD4(+) T cells was only involved in STAT-4 pathway but not STAT-1. Poly-functional CD4(+) T cells were contributed to generation and progress of varies diseases and our studies provide basic theoretics for the designs of vaccine and therapies of diseases. PMID:26566861

  7. Elimination of self-reactive CD8+, but not CD4+, T cells by a peripheral immune mechanism

    SciTech Connect

    Rammensee, H.G.; Huegin, D. )

    1990-03-01

    Unirradiated (BALB/c X B6)F1 recipients of lymphocytes from either parent or (B6 X DBA/2)F2 recipients of DBA/2 parental lymphocytes specifically remove the function of donor-derived F1-reactive CTL from the spleen, since such cells could not be recovered 1 week after injection. However, donor-derived CTL specific for third-party antigens, as well as donor-derived F1-reactive CD4+ T cells could be recovered. In contrast, CTL in spleens from recipients sublethally irradiated prior to injections consisted predominantly of F1-reactive CTL in all strain combinations tested. Athymic BALB/c nude mice grafted with fetal thymus of B6 develop a T cell compartment tolerant of BALB/c and B6, like (BALB/c X B6)F1 animals. However, unlike the F1 mice, the thymus-grafted nude mice were not able to eliminate B6-reactive lymphocytes after injection of normal BALB/c spleen cells. Our data indicate the existence of a peripheral immune mechanism capable of selectively eliminating self-reactive CD8+ CTL, but not CD4+, T cells. This mechanism requires self antigen expressed on radiosensitive cells. The presence of T cells tolerant to self antigen by thymic negative selection is not sufficient and perhaps not required. Most likely, this mechanism is involved in the relative resistance to lethal GVHR mediated by parental CD8+ T cells in parent-into-F1 situations.

  8. Involvement of CD8+ T Cells in Multiple Sclerosis

    PubMed Central

    Salou, Marion; Nicol, Bryan; Garcia, Alexandra; Laplaud, David-Axel

    2015-01-01

    Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system characterized by focal demyelination patches associated with inflammatory infiltrates containing T lymphocytes. For decades, CD4+ T cells have been recognized as playing a major role in the disease, especially in animal models, which has led to the development of several therapies. However, interest has recently developed in the involvement of CD8+ T cells in MS following the analysis of infiltrating T cells in human brain lesions. A broad range of evidence now suggests that the pathological role of this T cell subset in MS may have been underestimated. In this review, we summarize the literature implicating CD8+ T cells in the pathophysiology of MS. We present data from studies in the fields of genetics, anatomopathology and immunology, mainly in humans but also in animal models of MS. Altogether, this strongly suggests that CD8+ T cells may be major effectors in the disease process, and that the development of treatments specifically targeting this subset would be germane. PMID:26635816

  9. Leukemia -- Chronic T-Cell Lymphocytic

    MedlinePLUS

    ... Chronic T-Cell Lymphocytic: Overview Print to PDF Leukemia - Chronic T-Cell Lymphocytic: Overview Approved by the ... as a roadmap to this full guide. About leukemia Leukemia is a cancer of the blood cells. ...

  10. A combination of local inflammation and central memory T cells potentiates immunotherapy in the skin

    PubMed Central

    Fiorenza, Salvatore; Kenna, Tony J.; Comerford, Iain; McColl, Shaun; Steptoe, Raymond J.; Leggatt, Graham R.; Frazer, Ian H.

    2012-01-01

    Adoptive T cell therapy utilises the specificity of the adaptive immune system to target cancer and virally infected cells. Yet the mechanism and means by which to enhance T cell function are incompletely described, especially in the skin. Here, we utilise a murine model of immunotherapy to optimise cell-mediated immunity in the skin. We show that in vitro derived central but not effector memory-like T cells bring about rapid regression of skin expressing cognate antigen as a transgene in keratinocytes. Local inflammation induced by the TLR7 receptor agonist, imiquimod, subtly yet reproducibly decreases time to skin graft rejection elicited by central but not effector memory T cells in an immunodeficient mouse model. Local CCL4, a chemokine liberated by TLR7 agonism, similarly enhances central memory T cell function. In this model, IL-2 facilitates the development of in vivo of effector function from central memory but not effector memory T cells. In a model of T cell tolerogenesis, we further show that adoptively transferred central but not effector memory T cells can give rise to successful cutaneous immunity that is dependent on a local inflammatory cue in the target tissue at the time of adoptive T cell transfer. Thus, adoptive T cell therapy efficacy can be enhanced if CD8+ T cells with a central memory T cell phenotype are transferred and IL-2 is present with contemporaneous local inflammation. PMID:23144496

  11. CD8+ T Cell Responses to Plasmodium and Intracellular Parasites

    PubMed Central

    Villarino, Nicolas; Schmidt, Nathan W.

    2013-01-01

    Parasitic protozoa are major threats to human health affecting millions of people around the world. Control of these infections by the host immune system relies on a myriad of immunological mechanisms that includes both humoral and cellular immunity. CD8+ T cells contribute to the control of these parasitic infections in both animals and humans. Here, we will focus on the CD8+ T cell response against a subset of these protozoa: Plasmodium, Toxoplasma gondii, Leishmania and Trypanosoma cruzi, with an emphasis on experimental rodent systems. It is evident a complex interaction occurs between CD8+ T cells and the invading protozoa. A detailed understanding of how CD8+ T cells mediate protection should provide the basis for the development of effective vaccines that prevent and control infections by these parasites. PMID:24741372

  12. Hepatic effector CD8+ T-cell dynamics

    PubMed Central

    Iannacone, Matteo

    2015-01-01

    CD8+ T cells play a critical role in hepatitis B virus (HBV) pathogenesis. During acute, self-limited infections, these cells are instrumental to viral clearance; in chronic settings, they sustain repetitive cycles of hepatocellular necrosis that promote hepatocellular carcinoma development. Both CD8+ T-cell defensive and destructive functions are mediated by antigen-experienced effector cells and depend on the ability of these cells to migrate to the liver, recognize hepatocellular antigens and perform effector functions. Understanding the signals that modulate the spatiotemporal dynamics of CD8+ T cells in the liver, particularly in the context of antigen recognition, is therefore critical to gaining insight into the pathogenesis of acute and chronic HBV infection. Here, we highlight recent data on how effector CD8+ T cells traffic within the liver, and we discuss the potential for novel imaging techniques to shed light on this important aspect of HBV pathogenesis. PMID:25242274

  13. Stochastic modelling of T cell repertoire maintenance

    E-print Network

    Wirosoetisno, Djoko

    thymus lymph nodes lymphoid vessels (tonsils) thymus + bone marrow = central lymphoid organs lymph nodes repertoire DAMTP 2008 3 / 42 #12;Immunological background APCs T cells lymph node infected peripheral tissue lymph node. 3 T cells display on their surface peptide receptors. 4 T cells continuously recirculate

  14. Memory Antitumor T-Cells Resist Inhibition by Immune Suppressor Cells.

    PubMed

    Gao, Yanhua; Whitaker-Dowling, Patricia; Bergman, Ira

    2015-09-01

    Cancer immune therapy is difficult partly because several classes of suppressor cells, including regulatory T-cells and macrophage-derived suppressor cells, inhibit the antitumor T-cell response. We used treatment studies of implanted tumors in mice to demonstrate that the same inhibitory cells that abrogated an acute therapeutic T-cell response to established tumor did not inhibit the therapeutic response produced by memory T-cells. Generating antitumor memory T-cells may be a highly potent strategy against cancer with late developing metastases. PMID:26254347

  15. Regulatory T Cell Activity and Signs of T Cell Unresponsiveness in Bovine Paratuberculosis

    PubMed Central

    Roussey, Jonathan A.; Steibel, Juan P.; Coussens, Paul M.

    2014-01-01

    Johne’s disease, caused by infection with Mycobacterium avium subspecies paratuberculosis (MAP), is a wasting disease of ruminants displaying a long subclinical stage of infection followed by clinical disease characterized by severe diarrhea, wasting, and premature death. Immunologically, subclinical disease is characterized by a Th1 response effective at controlling intracellular infections such as that caused by MAP. In late subclinical disease, the Th1 response subsides and a non-protective Th2 response becomes prominent. One hypothesis for this shift in immune paradigm is that a population of MAP-reactive regulatory T cells (Tregs) develops during subclinical infection, limiting Th1-type responses to MAP antigens. To investigate this, we sought to accomplish the following: (1) determine if CD4+CD25? T cells exposed to MAP-infected macrophages develop a Treg phenotype, (2) develop a method to expand the relative abundance of Tregs in bovine peripheral blood lymphocyte populations, and (3) identify functional activities of expanded Tregs when combined with autologous peripheral blood mononuclear cells (PBMCs) and live MAP. We found that CD4+CD25? T cells exposed to MAP-infected macrophages from cows with Johne’s disease do not show signs of a Treg phenotype and appear unresponsive to MAP antigens. A method for Treg expansion was successfully developed; however, based on results obtained in the subsequent functional studies it appears that these Tregs are not MAP-specific. Overall, it seems that T cell unresponsiveness, rather than Treg activity, is driving the Th1-to-Th2 immune shift observed during Johne’s disease. Further, we have successfully developed a method to enrich non-specific bovine Tregs that exert suppressive effects against Th1 cytokine production.

  16. CD46 engagement on human CD4+ T cells produces T regulatory type 1-like regulation of antimycobacterial T cell responses.

    PubMed

    Truscott, Steven M; Abate, Getahun; Price, Jeffrey D; Kemper, Claudia; Atkinson, John P; Hoft, Daniel F

    2010-12-01

    Understanding the regulation of human immune responses is critical for vaccine development and treating infectious diseases. We have previously shown that simultaneous engagement of the T cell receptor (TCR) and complement regulator CD46 on human CD4(+) T cells in the presence of interleukin-2 (IL-2) induces potent secretion of the immunomodulatory cytokine IL-10. These T cells mediate IL-10-dependent suppression of bystander CD4(+) T cells activated in vitro with anti-CD3 and anti-CD28 costimulation, reflecting a T regulatory type 1 (Tr1)-like phenotype. However, CD46-mediated negative regulation of pathogen-specific T cells has not been described. Therefore, we studied the ability of CD46-activated human CD4(+) T cells to suppress T cell responses to Mycobacterium bovis BCG, the live vaccine that provides infants protection against the major human pathogen Mycobacterium tuberculosis. Our results demonstrate that soluble factors secreted by CD46-activated human CD4(+) T cells suppress mycobacterium-specific CD4(+), CD8(+), and ?(9)?(2) TCR(+) T cells. Dendritic cell functions were not downregulated in our experiments, indicating that CD46-triggered factors directly suppress pathogen-specific T cells. Interestingly, IL-10 appeared to play a less pronounced role in our system, especially in the suppression of ?(9)?(2) TCR(+) T cells, suggesting the presence of additional undiscovered soluble immunoregulatory factors. Blocking endogenous CD46 signaling 3 days after mycobacterial infection enhanced BCG-specific T cell responses in a subset of volunteers. Taken together, these results indicate that CD46-dependent negative regulatory mechanisms can impair T cell responses vital for immune defense against mycobacteria. Therefore, modulating CD46-induced immune regulation could be integral to the development of improved tuberculosis therapeutics or vaccines. PMID:20921150

  17. Differentiation and functional maturation of bone marrow-derived intestinal epithelial T cells expressing membrane T cell receptor in athymic radiation chimeras

    SciTech Connect

    Mosley, R.L.; Styre, D.; Klein, J.R. )

    1990-09-01

    The thymus dependency of murine intestinal intraepithelial lymphocytes (IEL) was studied in an athymic F1----parent radiation chimera model. IEL, although not splenic or lymph node lymphocytes, from athymic chimeras displayed normal levels of cells bearing the class-specific T cell Ag, CD4 and CD8; the TCR-associated molecule, CD3; and the Thy-1 Ag. Moreover, two-color flow cytometric analyses of IEL from athymic mice demonstrated regulated expression of T cell Ag characteristic of IEL subset populations from thymus-bearing mice. In immunoprecipitation experiments, surface TCR-alpha beta or TCR-gamma delta were expressed on IEL, although not on splenic lymphocytes, from athymic chimeras. That IEL from athymic chimeras constituted a population of functionally mature effector cells activated in situ, similar to IEL from thymus-bearing mice, was demonstrated by the presence of CD3-mediated lytic activity of athymic lethally irradiated bone marrow reconstituted IEL. These data provide compelling evidence that intestinal T cells do not require thymic influence for maturation and development, and demonstrate that the microenvironment of the intestinal epithelium is uniquely adapted to regulate IEL differentiation.

  18. Requirement for CD28 in Effector Regulatory T Cell Differentiation, CCR6 Induction, and Skin Homing.

    PubMed

    Zhang, Ruan; Borges, Christopher M; Fan, Martin Y; Harris, John E; Turka, Laurence A

    2015-11-01

    The skin, similar to most nonlymphoid tissues, contains substantial numbers of T cells. Among these, memory T cells serve a sentinel role to protect against pathogens, and regulatory T cells (Tregs) terminate immune responses as a check against unrestrained inflammation. Previously, we created conditional knockout mice with Treg-specific deletion of CD28. Although these mice have normal numbers of Tregs, these cells have lower levels of CTLA-4, PD-1, and CCR6, and the animals develop systemic autoimmunity characterized by prominent skin inflammation. In this study, we have performed a detailed analysis of the skin disease in these mice. Our data show that Treg-expressed CD28 is required for optimal maturation of CD44(lo)CD62L(hi) central Tregs into CD44(hi)CD62L(lo) effector Tregs (eTregs), as well as induction of CCR6 among the cells that do become eTregs. Although CD28-deficient Tregs are able to regulate inflammation normally when injected directly into the skin, they fail to home properly to inflamed skin. Collectively, these results suggest a key role for CD28 costimulation in promoting a central Treg to eTreg transition with appropriate upregulation of chemokine receptors such as CCR6 that are required for tissue homing. PMID:26408668

  19. Disturbed T Cell Signaling and Altered Th17 and Regulatory T Cell Subsets in the Pathogenesis of Systemic Lupus Erythematosus

    PubMed Central

    Rother, Nils; van der Vlag, Johan

    2015-01-01

    Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the presence of autoantibodies against nuclear components. Circulating immune complexes of chromatin and autoantibodies deposit in various tissues leading to inflammation and tissue damage. It has been well documented that autoimmunity in SLE depends on autoreactive T cells. In this review, we summarize the literature that addresses the roles of T cell signaling, and Th17 and regulatory T cells (Tregs) in the development of SLE. T cell receptor (TCR) signaling appears to be aberrant in T cells of patients with SLE. In particular, defects in the TCR? chain, Syk kinase, and calcium signaling molecules have been associated with SLE, which leads to hyperresponsive autoreactive T cells. Furthermore, in patients with SLE increased numbers of autoreactive Th17 cells have been documented, and Th17 cells appear to be responsible for tissue inflammation and damage. In addition, reduced numbers of Tregs as well as Tregs with an impaired regulatory function have been associated with SLE. The altered balance between the number of Tregs and Th17 cells in SLE may result from changes in the cytokine milieu that favors the development of Th17 cells over Tregs. PMID:26648939

  20. Tracking and treating activated T cells

    PubMed Central

    Kim, N.H.; Nadithe, V.; Elsayed, M.; Merkel, O.M.

    2014-01-01

    Upon activation, T cells of various subsets are the most important mediators in cell-mediated immune responses. Activated T cells play an important role in immune system related diseases such as chronic inflammatory diseases, viral infections, autoimmune disease, transplant rejection, Crohn disease, diabetes, and many more. Therefore, efforts have been made to both visualize and treat activated T cells specifically. This review summarizes imaging approaches and selective therapeutics for activated T cells and gives an outlook on how tracking and treating can be combined into theragnositc agents for activated T cells. PMID:24660025

  1. T Cell Signaling Targets for Enhancing Regulatory or Effector Function

    PubMed Central

    Pan, Fan; Fan, Huimin; Liu, Zhongmin; Jiang, Shuiping

    2015-01-01

    To respond to infection, resting or naïve T cells must undergo activation, clonal expansion, and differentiation into specialized functional subsets of effector T cells. However, to prevent excessive or self-destructive immune responses, regulatory T cells (Tregs) are instrumental in suppressing the activation and function of effector cells, including effector T cells. The transcription factor Forkhead box P3 (Foxp3) regulates the expression of genes involved in the development and function of Tregs. Foxp3 interacts with other transcription factors and with epigenetic elements such as histone deacetylases (HDACs) and histone acetyltransferases. Treg suppressive function can be increased by exposure to HDAC inhibitors. The individual contributions of different HDAC family members to Treg function and their respective mechanisms of action, however, remain unclear. A study showed that HDAC6, HDAC9, and Sirtuin-1 had distinct effects on Foxp3 expression and function, suggesting that selectively targeting HDACs individually or in combination may enhance Treg stability and suppressive function. Another study showed that the receptor programmed death 1 (PD-1), a well-known inhibitor of T cell activation, halted cell cycle progression in effector T cells by inhibiting the transcription of the gene encoding the substrate-recognition component (Skp2) of the ubiquitin ligase SCFSkp2. Together, these findings reveal new signaling targets for enhancing Treg or effector T cell function that may be helpful in designing future therapies, either to increase Treg suppressive function in transplantation and autoimmune diseases or to block PD-1 function, thus increasing the magnitude of antiviral or antitumor immune responses of effector T cells. PMID:22855503

  2. T-cell immunity to influenza A viruses.

    PubMed

    Grant, Emma J; Chen, Li; Quiñones-Parra, Sergio; Pang, Ken; Kedzierska, Katherine; Chen, Weisan

    2014-01-01

    Influenza infection remains a global threat to human health. Influenza viruses are normally controlled by antibodies specific for the surface glycoproteins hemagglutinin (HA) and neuraminidase (NA). Standard influenza vaccines are aimed at inducing these antibodies, but they must be administered annually and can be rendered ineffective since different strains circulate from year to year and vary considerably in their individual HA and NA profiles. Influenza-specific T cells have been shown to be protective in animal models and typically recognize the more conserved internal influenza proteins. Improving our understanding of influenza-specific T-cell responses, including immunodominance, specific epitope sequences, strain-related epitope variation, host/virus interaction, and the balance between immunity versus immunopathology, will be important to improve future T-cell-based vaccines, which promise broader strain coverage and longer-lasting protection than current standard vaccines. PMID:24579700

  3. Functional and Phenotypic Plasticity of CD4+ T Cell Subsets

    PubMed Central

    Caza, Tiffany; Landas, Steve

    2015-01-01

    The remarkable plasticity of CD4+ T cells allows individuals to respond to environmental stimuli in a context-dependent manner. A balance of CD4+ T cell subsets is critical to mount responses against pathogen challenges to prevent inappropriate activation, to maintain tolerance, and to participate in antitumor immune responses. Specification of subsets is a process beginning in intrathymic development and continuing within the circulation. It is highly flexible to adapt to differences in nutrient availability and the tissue microenvironment. CD4+ T cell subsets have significant cross talk, with the ability to “dedifferentiate” given appropriate environmental signals. This ability is dependent on the metabolic status of the cell, with mTOR acting as the rheostat. Autoimmune and antitumor immune responses are regulated by the balance between regulatory T cells and Th17 cells. When a homeostatic balance of subsets is not maintained, immunopathology can result. CD4+ T cells carry complex roles within tumor microenvironments, with context-dependent immune responses influenced by oncogenic drivers and the presence of inflammation. Here, we examine the signals involved in CD4+ T cell specification towards each subset, interconnectedness of cytokine networks, impact of mTOR signaling, and cellular metabolism in lineage specification and provide a supplement describing techniques to study these processes. PMID:26583116

  4. Immature MEF2C-dysregulated T-cell leukemia patients have an early T-cell precursor acute lymphoblastic leukemia gene signature and typically have non-rearranged T-cell receptors

    PubMed Central

    Zuurbier, Linda; Gutierrez, Alejandro; Mullighan, Charles G.; Canté-Barrett, Kirsten; Gevaert, A. Olivier; de Rooi, Johan; Li, Yunlei; Smits, Willem K.; Buijs-Gladdines, Jessica G.C.A.M.; Sonneveld, Edwin; Look, A. Thomas; Horstmann, Martin; Pieters, Rob; Meijerink, Jules P.P.

    2014-01-01

    Three distinct immature T-cell acute lymphoblastic leukemia entities have been described including cases that express an early T-cell precursor immunophenotype or expression profile, immature MEF2C-dysregulated T-cell acute lymphoblastic leukemia cluster cases based on gene expression analysis (immature cluster) and cases that retain non-rearranged TRG@ loci. Early T-cell precursor acute lymphoblastic leukemia cases exclusively overlap with immature cluster samples based on the expression of early T-cell precursor acute lymphoblastic leukemia signature genes, indicating that both are featuring a single disease entity. Patients lacking TRG@ rearrangements represent only 40% of immature cluster cases, but no further evidence was found to suggest that cases with absence of bi-allelic TRG@ deletions reflect a distinct and even more immature disease entity. Immature cluster/early T-cell precursor acute lymphoblastic leukemia cases are strongly enriched for genes expressed in hematopoietic stem cells as well as genes expressed in normal early thymocyte progenitor or double negative-2A T-cell subsets. Identification of early T-cell precursor acute lymphoblastic leukemia cases solely by defined immunophenotypic criteria strongly underestimates the number of cases that have a corresponding gene signature. However, early T-cell precursor acute lymphoblastic leukemia samples correlate best with a CD1 negative, CD4 and CD8 double negative immunophenotype with expression of CD34 and/or myeloid markers CD13 or CD33. Unlike various other studies, immature cluster/early T-cell precursor acute lymphoblastic leukemia patients treated on the COALL-97 protocol did not have an overall inferior outcome, and demonstrated equal sensitivity levels to most conventional therapeutic drugs compared to other pediatric T-cell acute lymphoblastic leukemia patients. PMID:23975177

  5. Contact-dependent T cell activation and T cell stopping require talin1!

    PubMed Central

    Wernimont, Sarah A; Wiemer, Andrew J; Bennin, David A; Monkley, Susan J; Ludwig, Thomas; Critchley, David R; Huttenlocher, Anna

    2011-01-01

    T cell:antigen presenting cell (APC) contact initiates T cell activation and is maintained by the integrin LFA-1. Talin1, a LFA-1 regulator, localizes to the immune synapse with unknown roles in T cell activation. Here, we show that talin1-deficient T cells have defects in contact-dependent T cell stopping and proliferation. While talin1-deficient T cells did not form stable interactions with APCs, transient contacts were sufficient to induce signaling. In contrast to prior models, LFA-1 polarized to T cell:APC contacts in talin1-deficient T cells but vinculin and F-actin polarization at the immune synapse was impaired. These results indicate that T cell proliferation requires sustained, talin1-mediated T cell:APC interactions and that talin1 is necessary for F-actin polarization and the stability of immune synapses. PMID:22075696

  6. Altered CELF1 binding to target transcripts in malignant T cells.

    PubMed

    Bohjanen, Paul R; Moua, Mai Lee; Guo, Liang; Taye, Ammanuel; Vlasova-St Louis, Irina A

    2015-10-01

    The RNA-binding protein, CELF1, binds to a regulatory sequence known as the GU-rich element (GRE) and controls a network of mRNA transcripts that regulate cellular activation, proliferation, and apoptosis. We performed immunoprecipitation using an anti-CELF1 antibody, followed by identification of copurified transcripts using microarrays. We found that CELF1 is bound to a distinct set of target transcripts in the H9 and Jurkat malignant T-cell lines, compared with primary human T cells. CELF1 was not phosphorylated in resting normal T cells, but in malignant T cells, phosphorylation of CELF1 correlated with its inability to bind to GRE-containing mRNAs that served as CELF1 targets in normal T cells. Lack of binding by CELF1 to these mRNAs in malignant T cells correlated with stabilization and increased expression of these transcripts. Several of these GRE-containing transcripts that encode regulators of cell growth were also stabilized and up-regulated in primary tumor cells from patients with T-cell acute lymphoblastic leukemia. Interestingly, transcripts encoding numerous suppressors of cell proliferation that served as targets of CELF1 in malignant T cells, but not normal T cells, exhibited accelerated degradation and reduced expression in malignant compared with normal T cells, consistent with the known function of CELF1 to mediate degradation of bound transcripts. Overall, CELF1 dysfunction in malignant T cells led to the up-regulation of a subset of GRE-containing transcripts that promote cell growth and down-regulation of another subset that suppress cell growth, producing a net effect that would drive a malignant phenotype. PMID:26249002

  7. Rescue of notch-1 signaling in antigen-specific CD8+ T cells overcomes tumor-induced T-cell suppression and enhances immunotherapy in cancer.

    PubMed

    Sierra, Rosa A; Thevenot, Paul; Raber, Patrick L; Cui, Yan; Parsons, Chris; Ochoa, Augusto C; Trillo-Tinoco, Jimena; Del Valle, Luis; Rodriguez, Paulo C

    2014-08-01

    An impaired antitumor immunity is found in patients with cancer and represents a major obstacle in the successful development of different forms of immunotherapy. Signaling through Notch receptors regulates the differentiation and function of many cell types, including immune cells. However, the effect of Notch in CD8(+) T-cell responses in tumors remains unclear. Thus, we aimed to determine the role of Notch signaling in CD8(+) T cells in the induction of tumor-induced suppression. Our results using conditional knockout mice show that Notch-1 and Notch-2 were critical for the proliferation and IFN? production of activated CD8(+) T cells and were significantly decreased in tumor-infiltrating T cells. Conditional transgenic expression of Notch-1 intracellular domain (N1IC) in antigen-specific CD8(+) T cells did not affect activation or proliferation of CD8(+) T cells, but induced a central memory phenotype and increased cytotoxicity effects and granzyme B levels. Consequently, a higher antitumor response and resistance to tumor-induced tolerance were found after adoptive transfer of N1IC-transgenic CD8(+) T cells into tumor-bearing mice. Additional results showed that myeloid-derived suppressor cells (MDSC) blocked the expression of Notch-1 and Notch-2 in T cells through nitric oxide-dependent mechanisms. Interestingly, N1IC overexpression rendered CD8(+) T cells resistant to the tolerogenic effect induced by MDSC in vivo. Together, the results suggest the key role of Notch in the suppression of CD8(+) T-cell responses in tumors and the therapeutic potential of N1IC in antigen-specific CD8(+) T cells to reverse T-cell suppression and increase the efficacy of T cell-based immunotherapies in cancer. PMID:24830414

  8. Transcriptional regulation of T cell metabolism.

    PubMed

    Hough, Kenneth P; Chisolm, Danielle A; Weinmann, Amy S

    2015-12-01

    T cells express specific metabolic programs to promote diverse cellular differentiation states. The activation of naïve T cells upregulates the expression of genes encoding components of the glycolysis, glutaminolysis, and lipid biosynthesis pathways to promote robust proliferation and effector T cell activity. In contrast, memory T cells downregulate these pathways and predominantly rely on catabolic pathways for long-term survival. Dynamic changes in the expression of the genes encoding components of metabolic pathways in part define which metabolic programs are utilized in diverse T cell states. The current data suggest that key transcription factors involved in T cell specialization decisions, including T-bet, Bcl-6, HIF1, IRF4 and Myc, link the selective programming of cellular metabolism with fate decisions. In this review, we will highlight the transcriptional regulatory events that define metabolic pathways involved in effector and memory T cell differentiation. PMID:26298576

  9. Application of the pMHC Array to Characterise Tumour Antigen Specific T Cell Populations in Leukaemia Patients at Disease Diagnosis

    PubMed Central

    Lee, Cindy; Publicover, Amy; Khan, Ghazala; Smits, Evelien L.; Sigurdardottir, Dagmar; Arno, Matthew; Li, Demin; Mills, Ken I.; Pulford, Karen; Banham, Alison H.; van Tendeloo, Viggo; Mufti, Ghulam J.; Rammensee, Hans-Georg; Elliott, Tim J.; Orchard, Kim H.; Guinn, Barbara-ann

    2015-01-01

    Immunotherapy treatments for cancer are becoming increasingly successful, however to further improve our understanding of the T-cell recognition involved in effective responses and to encourage moves towards the development of personalised treatments for leukaemia immunotherapy, precise antigenic targets in individual patients have been identified. Cellular arrays using peptide-MHC (pMHC) tetramers allow the simultaneous detection of different antigen specific T-cell populations naturally circulating in patients and normal donors. We have developed the pMHC array to detect CD8+ T-cell populations in leukaemia patients that recognise epitopes within viral antigens (cytomegalovirus (CMV) and influenza (Flu)) and leukaemia antigens (including Per Arnt Sim domain 1 (PASD1), MelanA, Wilms’ Tumour (WT1) and tyrosinase). We show that the pMHC array is at least as sensitive as flow cytometry and has the potential to rapidly identify more than 40 specific T-cell populations in a small sample of T-cells (0.8–1.4 x 106). Fourteen of the twenty-six acute myeloid leukaemia (AML) patients analysed had T cells that recognised tumour antigen epitopes, and eight of these recognised PASD1 epitopes. Other tumour epitopes recognised were MelanA (n = 3), tyrosinase (n = 3) and WT1126-134 (n = 1). One of the seven acute lymphocytic leukaemia (ALL) patients analysed had T cells that recognised the MUC1950-958 epitope. In the future the pMHC array may be used provide point of care T-cell analyses, predict patient response to conventional therapy and direct personalised immunotherapy for patients. PMID:26492414

  10. The bi-specific CD3 × NCAM antibody: a model to preactivate T cells prior to tumour cell lysis

    PubMed Central

    JENSEN, M; ERNESTUS, K; KEMSHEAD, J; KLEHR, M; VON BERGWELT-BAILDON, M S; SCHINKÖTHE, T; SCHULTZE, J L; BERTHOLD, F

    2003-01-01

    To target the neural cell adhesion molecule (NCAM, CD56) on neuroblastoma by T cell-based immunotherapy we have generated a bi-specific CD3 × NCAM antibody (OE-1). This antibody can be used to redirect T cells to NCAM+ cells. Expectedly, the antibody binds specifically to NCAM+ neuroblastoma cells and CD3+ T cells. OE-1 induces T cell activation, expansion and effector function in peripheral blood mononuclear cell (PBMC)-derived CD4+ and CD8+ T cells. T cell activation was shown to depend on the presence of normal natural killer (NK) cells in the culture. Interestingly, while PBMC- derived T cells were activated by OE-1, NK cells were almost completely depleted, suggesting that T cells activated by OE-1 deleted the NK cells. Activated CD4+ and CD8+ T cells differentiate into a larger CCR7+ central memory and a smaller CCR7– effector memory cell population. Most importantly, preactivated T cells were highly cytotoxic for neuroblastoma cells. In eight of 11 experiments tumour-directed cytotoxicity was enhanced when NK cells were present during preactivation with OE-1. These data strongly support a bi-phasic therapeutic concept of primarily stimulating T cells with the bi-specific antibody in the presence of normal NCAM+ cells to induce T cell activation, migratory capacity and finally tumour cell lysis. PMID:14616785

  11. The Timing of Stimulation and IL-2 Signaling Regulate Secondary CD8 T Cell Responses

    PubMed Central

    Khan, Shaniya H.; Martin, Matthew D.; Starbeck-Miller, Gabriel R.; Xue, Hai-Hui; Harty, John T.; Badovinac, Vladimir P.

    2015-01-01

    Abstract Memory CD8 T cells provide protection to immune hosts by eliminating pathogen-infected cells during re-infection. While parameters influencing the generation of primary (1°) CD8 T cells are well established, the factors controlling the development of secondary (2°) CD8 T cell responses remain largely unknown. Here, we address the mechanisms involved in the generation and development of 2° memory (M) CD8 T cells. We observed that the time at which 1° M CD8 T cells enter into immune response impacts their fate and differentiation into 2° M CD8 T cells. Late-entry of 1° M CD8 T cells into an immune response (relative to the onset of infection) not only facilitated the expression of transcription factors associated with memory formation in 2° effector CD8 T cells, but also influenced the ability of 2° M CD8 T cells to localize within the lymph nodes, produce IL-2, and undergo Ag-driven proliferation. The timing of stimulation of 1° M CD8 T cells also impacted the duration of expression of the high-affinity IL-2 receptor (CD25) on 2° effector CD8 T cells and their sensitivity to IL-2 signaling. Importantly, by blocking or enhancing IL-2 signaling in developing 2° CD8 T cells, we provide direct evidence for the role of IL-2 in controlling the differentiation of Ag-driven 2° CD8 T cell responses. Thus, our data suggest that the process of 1° M to 2° M CD8 T cell differentiation is not fixed and can be manipulated, a notion with relevance for the design of future prime-boost vaccination approaches. PMID:26431533

  12. BIM Deficiency Protects NOD Mice From Diabetes by Diverting Thymocytes to Regulatory T Cells.

    PubMed

    Krishnamurthy, Balasubramanian; Chee, Jonathan; Jhala, Gaurang; Trivedi, Prerak; Catterall, Tara; Selck, Claudia; Gurzov, Esteban N; Brodnicki, Thomas C; Graham, Kate L; Wali, Jibran A; Zhan, Yifan; Gray, Daniel; Strasser, Andreas; Allison, Janette; Thomas, Helen E; Kay, Thomas W H

    2015-09-01

    Because regulatory T-cell (Treg) development can be induced by the same agonist self-antigens that induce negative selection, perturbation of apoptosis will affect both negative selection and Treg development. But how the processes of thymocyte deletion versus Treg differentiation bifurcate and their relative importance for tolerance have not been studied in spontaneous organ-specific autoimmune disease. We addressed these questions by removing a critical mediator of thymocyte deletion, BIM, in the NOD mouse model of autoimmune diabetes. Despite substantial defects in the deletion of autoreactive thymocytes, BIM-deficient NOD (NODBim(-/-)) mice developed less insulitis and were protected from diabetes. BIM deficiency did not impair effector T-cell function; however, NODBim(-/-) mice had increased numbers of Tregs, including those specific for proinsulin, in the thymus and peripheral lymphoid tissues. Increased levels of Nur77, CD5, GITR, and phosphorylated I?B-? in thymocytes from NODBim(-/-) mice suggest that autoreactive cells receiving strong T-cell receptor signals that would normally delete them escape apoptosis and are diverted into the Treg pathway. Paradoxically, in the NOD model, reduced thymic deletion ameliorates autoimmune diabetes by increasing Tregs. Thus, modulating apoptosis may be one of the ways to increase antigen-specific Tregs and prevent autoimmune disease. PMID:25948683

  13. Signaling pathways in aged T cells – a reflection of T cell differentiation, cell senescence and host environment

    PubMed Central

    Goronzy, Jörg J.; Li, Guangjin; Yu, Mingcan; Weyand, Cornelia M.

    2012-01-01

    With increasing age, the ability of the immune system to protect against new antigenic challenges or to control chronic infections erodes. Decline in thymic function and cumulating antigenic experiences of acute and chronic infections threaten T cell homeostasis, but insufficiently explain the failing immune competence and the increased susceptibility for autoimmunity. Alterations in signaling pathways in the aging T cells account for many of the age-related defects. Signaling threshold calibrations seen with aging frequently built on mechanisms that are operational in T cell development and T cell differentiation or are adaptations to the changing environment in the aging host. Age-related changes in transcription of receptors and signaling molecules shift the balance towards inhibitory pathways, most dominantly seen in CD8 T cells and to a lesser degree in CD4 T cells. Prominent examples are the expression of negative regulatory receptors of the CD28 and the TNF receptor superfamilies as well the expression of various cytoplasmic and nuclear dual-specific phosphatases. PMID:22560928

  14. The catalytic activity of the kinase ZAP-70 mediates basal signaling and negative feedback of the T cell receptor pathway

    PubMed Central

    Cheng, Debra A; Kadlecek, Theresa A.; Cantor, Aaron J.; Kuriyan, John

    2015-01-01

    T cell activation must be properly regulated to ensure normal T cell development and effective immune responses to pathogens and transformed cells while avoiding autoimmunity. The mechanisms controlling the fine-tuning of T cell receptor (TCR) signaling and T cell activation are unclear. The Syk family kinase ? chain–associated protein kinase of 70 kD (ZAP-70) is a critical component of the TCR signaling machinery that leads to T cell activation. To elucidate potential feedback targets that are dependent on the kinase activity of ZAP-70, we performed a mass spectrometry–based, phosphoproteomic study to quantify temporal changes in phosphorylation patterns after inhibition of ZAP-70 catalytic activity. Our results provide insights into the fine-tuning of the T cell signaling network before and after TCR engagement. The data indicate that the kinase activity of ZAP-70 stimulates negative feedback pathways that target the Src family kinase Lck and modulate the phosphorylation patterns of the immunoreceptor tyrosine-based activation motifs (ITAMs) of the CD3 and ?-chain components of the TCR, and of downstream signaling molecules, including ZAP-70. We developed a computational model that provides a unified mechanistic explanation for the experimental findings on ITAM phosphorylation in wild-type cells, ZAP-70–deficient cells, and cells with inhibited ZAP-70 catalytic activity. This model incorporates negative feedback regulation of Lck activity by the kinase activity of ZAP-70 and makes unanticipated specific predictions for the order in which tyrosines in the ITAMs of TCR ?-chains must be phosphorylated to be consistent with the experimental data. PMID:25990959

  15. Subspecialization of Cxcr5+ T Cells

    PubMed Central

    Kim, Chang H.; Rott, Lusijah S.; Clark-Lewis, Ian; Campbell, Daniel J.; Wu, Lijun; Butcher, Eugene C.

    2001-01-01

    The T helper (Th) cell pool is composed of specialized cells with heterogeneous effector functions. Apart from Th1 and 2 cells, CXCR5+ T cells have been suggested to be another type of effector T cell specialized for B cell help. We show here that CXCR5+ T cells are heterogeneous, and we identify subsets of CXCR5+ CD4 T cells that differ in function and microenvironmental localization in secondary lymphoid tissues. CD57+CXCR5 T cells, hereafter termed germinal center Th (GC-Th) cells, are localized only in GCs, lack CCR7, and are highly responsive to the follicular chemokine B lymphocyte chemoattractant but not to the T cell zone EBI1-ligand chemokine. Importantly, GC-Th cells are much more efficient than CD57?CXCR5+ T cells or CXCR5? T cells in inducing antibody production from B cells. Consistent with their function, GC-Th cells produce elevated levels of interleukin 10 upon stimulation which, with other cytokines and costimulatory molecules, may help confer their B cell helper activity. Our results demonstrate that CXCR5+ T cells are functionally heterogeneous and that the GC-Th cells, a small subset of CXCR5+ T cells, are the key helpers for B cell differentiation and antibody production in lymphoid tissues. PMID:11413192

  16. Increased bronchial density of CD25+Foxp3+ regulatory T cells in occupational asthma: relationship to current smoking.

    PubMed

    Sjåheim, T B; Bjørtuft, Ø; Drabløs, P A; Kongerud, J; Halstensen, T S

    2013-05-01

    To identify activated T cell subset in the asthmatic bronchia, we developed a triple-colour immunohistofluorescence labelling technique on cryo-section to discriminate activated CD4+CD25+ T cells, (effector T cells) from Foxp3+ regulatory T cells (Treg). Additional coexpression of activation and proliferation markers was also examined in situ. Bronchial biopsies were taken from 20 aluminium potroom workers (12 smokers) with asthma (>12% reversibility), 15 non-asthmatic potroom workers (7 smokers) and 10 non-smoking, non-exposed controls. Non-smoking asthmatics had significantly higher subepithelial density of both Tregs, effector T cells, activated (HLA-DR+) CD8+ and activated CD4+ T cells. Moreover, both Tregs, effector T cells and CD8+ T cells proliferated in the non-smoking asthmatics, only. Although smoking asthmatics had no asthma-associated increase in bronchial T cell, both had a significantly increase in effector T cell to Treg ratios. The significantly increased bronchial density of Tregs, effector T cells, proliferative T cells and activated CD8+ T cells in non-smoking asthmatics clearly showed that both the effector T cells and the inhibitory Treg system were activated in asthma. PMID:23421612

  17. CD98 Heavy Chain Is a Potent Positive Regulator of CD4+ T Cell Proliferation and Interferon-? Production In Vivo

    PubMed Central

    Ishifune, Chieko; Tsumura, Hideki; Ito, Morihiro; Ito, Yasuhiko; Kitamura, Akiko; Maekawa, Yoichi; Yasutomo, Koji

    2015-01-01

    Upon their recognition of antigens presented by the MHC, T cell proliferation is vital for clonal expansion and the acquisition of effector functions, which are essential for mounting adaptive immune responses. The CD98 heavy chain (CD98hc, Slc3a2) plays a crucial role in the proliferation of both CD4+ and CD8+ T cells, although it is unclear if CD98hc directly regulates the T cell effector functions that are not linked with T cell proliferation in vivo. Here, we demonstrate that CD98hc is required for both CD4+ T cell proliferation and Th1 functional differentiation. T cell-specific deletion of CD98hc did not affect T cell development in the thymus. CD98hc-deficient CD4+ T cells proliferated in vivo more slowly as compared with control T cells. C57BL/6 mice lacking CD98hc in their CD4+ T cells could not control Leishmania major infections due to lowered IFN-? production, even with massive CD4+ T cell proliferation. CD98hc-deficient CD4+ T cells exhibited lower IFN-? production compared with wild-type T cells, even when comparing IFN-? expression in cells that underwent the same number of cell divisions. Therefore, these data indicate that CD98hc is required for CD4+ T cell expansion and functional Th1 differentiation in vivo, and suggest that CD98hc might be a good target for treating Th1-mediated immune disorders. PMID:26444422

  18. ?? T cells and Th17 cytokines in Hypersensitivity Pneumonitis and Lung Fibrosis

    PubMed Central

    Simonian, Philip L.; Roark, Christina L.; Born, Willi K.; O’Brien, Rebecca L.; Fontenot, Andrew P.

    2009-01-01

    Hypersensitivity pneumonitis (HP) is an inflammatory lung disease caused by repeated inhalation of aerosolized antigens. With chronic exposure to an inhaled antigen, patients are at risk of developing irreversible pulmonary fibrosis and increased morbidity and mortality. Although ?? T cells have been shown to be important in the pathogenesis of HP, ?? T cells also accumulate in the bronchoalveolar lavage of patients with HP. ?? T cells represent a distinct lymphocyte subset, whose primary function is not well understood. In contrast to ?? T cells, ?? T cells recognize unprocessed antigens such as those upregulated on injured or stressed epithelial cells. In a murine model of HP induced by exposure to the ubiquitous microorganism, Bacillus subtilis, ?? T cells expressing the canonical V?6/V?1 T cell receptor were dramatically expanded in the lung. The predominant cytokines expressed by this ?? T cell subset were Th17 cytokines that were critical for bacterial clearance and the resolution of lung inflammation. Th17-expressing ?? T cells are also expanded in other murine models of lung infection and inflammation, suggesting that these cells play a sentinel role in mucosal immunity. Thus, an increased understanding of ?? T cells that express Th17 cytokines in HP and other inflammatory lung diseases may lead to the development of novel therapeutic and clinical strategies that prevent the development of fibrotic lung disease. PMID:19840763

  19. IL-10-producing CD4+ T cells negatively regulate fucosylation of epithelial cells in the gut

    PubMed Central

    Goto, Yoshiyuki; Lamichhane, Aayam; Kamioka, Mariko; Sato, Shintaro; Honda, Kenya; Kunisawa, Jun; Kiyono, Hiroshi

    2015-01-01

    Fucosylated glycans on the surface of epithelial cells (ECs) regulate intestinal homeostasis by serving as attachment receptors and a nutrient source for some species of bacteria. We show here that epithelial fucosylation in the ileum is negatively regulated by IL-10-producing CD4+ T cells. The number of fucosylated ECs was increased in the ileum of mice lacking T cells, especially those expressing ?? T cell receptor (TCR), CD4, and IL-10. No such effect was observed in mice lacking B cells. Adoptive transfer of ??TCR+ CD4+ T cells from normal mice, but not IL-10-deficient mice, normalized fucosylation of ECs. These findings suggest that IL-10-producing CD4+ T cells contribute to the maintenance of the function of ECs by regulating their fucosylation. PMID:26522513

  20. T cells and reactive oxygen species.

    PubMed

    Belikov, Aleksey V; Schraven, Burkhart; Simeoni, Luca

    2015-01-01

    Reactive oxygen species (ROS) have been long considered simply as harmful by-products of metabolism, which damage cellular proteins, lipids, and nucleic acids. ROS are also known as a weapon of phagocytes, employed against pathogens invading the host. However, during the last decade, an understanding has emerged that ROS also have important roles as signaling messengers in a multitude of pathways, in all cells, tissues, and organs. T lymphocytes are the key players of the adaptive immune response, which both coordinate other immune cells and destroy malignant and virus-infected cells. ROS have been extensively implicated in T-cell hyporesponsiveness, apoptosis, and activation. It has also become evident that the source, the kinetics, and the localization of ROS production all influence cell responses. Thus, the characterization of the precise mechanisms by which ROS are involved in the regulation of T-cell functions is important for our understanding of the immune response and for the development of new therapeutic treatments against immune-mediated diseases. This review summarizes the 30-year-long history of research on ROS in T lymphocytes, with the emphasis on the physiological roles of ROS. PMID:26471060

  1. Age-Dependent Changes in the Sphingolipid Composition of Mouse CD4+ T Cell Membranes and Immune Synapses Implicate Glucosylceramides in Age-Related T Cell Dysfunction

    PubMed Central

    Molano, Alberto; Huang, Zhaofeng; Marko, Melissa G.; Azzi, Angelo; Wu, Dayong; Wang, Elaine; Kelly, Samuel L.; Merrill, Alfred H.; Bunnell, Stephen C.; Meydani, Simin Nikbin

    2012-01-01

    To determine whether changes in sphingolipid composition are associated with age-related immune dysfunction, we analyzed the core sphingolipidome (i.e., all of the metabolites through the first headgroup additions) of young and aged CD4+ T cells. Since sphingolipids influence the biophysical properties of membranes, we evaluated the compositions of immune synapse (IS) and non-IS fractions prepared by magnetic immuno-isolation. Broadly, increased amounts of sphingomyelins, dihydrosphingomyelins and ceramides were found in aged CD4+ T cells. After normalizing for total sphingolipid content, a statistically significant decrease in the molar fraction of glucosylceramides was evident in both the non-IS and IS fractions of aged T cells. This change was balanced by less dramatic increases in the molar fractions of sphingomyelins and dihydrosphingomyelins in aged CD4+ T cells. In vitro, the direct or enzymatic enhancement of ceramide levels decreased CD4+ T cell proliferation without regard for the age of the responding T cells. In contrast, the in vitro inhibition of glucosylceramidase preferentially increased the proliferation of aged CD4+ T cells. These results suggest that reductions in glucosylceramide abundance contribute to age-related impairments in CD4+ T cell function. PMID:23110086

  2. Development of Phonetic Memory in Disabled and Normal Readers.

    ERIC Educational Resources Information Center

    Olson, Richard K.; And Others

    1984-01-01

    Tests the development of phonetic codes in the memory of 141 pairs of normal and disabled readers from 7.8 to 16.8 years of age. The measurement task assessed false-positive errors in recognition memory for foil words that rhymed with words in a memory list versus foil words that did not rhyme. (Author/CI)

  3. Defect in negative selection in lpr donor-derived T cells differentiating in non-lpr host thymus

    SciTech Connect

    Matsumoto, K.; Yoshikai, Y.; Asano, T.; Himeno, K.; Iwasaki, A.; Nomoto, K. )

    1991-01-01

    Transplantation of bone marrow cells of lpr/lpr mice into irradiated normal mice fails to develop massive lymphadenopathy or autoimmunity but causes severe graft-vs.-host-like syndrome. To elucidate an abnormality of lpr/lpr bone marrow-derived T cells, we transplanted bone marrow cells of Mlsb lpr/lpr mice into H-2-compatible Mlsa non-lpr mice. Although lpr/lpr T cell precursors repopulated the host thymus as well as +/+ cells, a proportion of CD4+CD8+ cells decreased, and that of both CD4- and CD8- single-positive cells increased compared with those of +/+ recipients. Notably, in MRL/lpr----AKR and C3H/lpr----AKR chimeras, CD4 single-positive thymocytes contained an increased number of V beta 6+ cells in spite of potentially deleting alleles of Mlsa, whereas V beta 6+ mature T cells were deleted in the MRL/+ ----AKR and C3H/+ ----AKR chimeras. There was no difference between MRL/+ ----AKR and MRL/lpr----AKR chimeras in their proportion of V beta 3+ cells because both host and donor strain lack the deleting alleles. Interleukin 2 receptor expression of mature T cells, in the thymus and lymph node, was obviously higher in the MRL/lpr----AKR chimeras, in particular in the forbidden V beta 6+ subset. Moreover, lpr donor-derived peripheral T cells showed vigorous anti-CD3 response. These results indicate that lpr-derived T cells escape not only tolerance-related clonal deletion but also some induction of unresponsiveness in the non-lpr thymus.

  4. TCR Signaling in T Cell Memory

    PubMed Central

    Daniels, Mark A.; Teixeiro, Emma

    2015-01-01

    T cell memory plays a critical role in our protection against pathogens and tumors. The antigen and its interaction with the T cell receptor (TCR) is one of the initiating elements that shape T cell memory together with inflammation and costimulation. Over the last decade, several transcription factors and signaling pathways that support memory programing have been identified. However, how TCR signals regulate them is still poorly understood. Recent studies have shown that the biochemical rules that govern T cell memory, strikingly, change depending on the TCR signal strength. Furthermore, TCR signal strength regulates the input of cytokine signaling, including pro-inflammatory cytokines. These highlight how tailoring antigenic signals can improve immune therapeutics. In this review, we focus on how TCR signaling regulates T cell memory and how the quantity and quality of TCR–peptide–MHC interactions impact the multiple fates a T cell can adopt in the memory pool. PMID:26697013

  5. ?? T cells in Experimental Autoimmune Encephalomyelitis: Early Trafficking Events and Cytokine Requirements

    PubMed Central

    Wohler, Jillian E.; Smith, Sherry S.; Zinn, Kurt R.; Bullard, Dan C.; Barnum, Scott R.

    2010-01-01

    We have previously shown that ?? T cells traffic to the CNS during EAE with concurrent increased expression of ?2-integrins and production of IFN-? and TNF-?. To extend these studies, we transferred bioluminescent ?? T cells to wild type mice and followed their movement through the acute stages of disease. We found that ?? T cells rapidly migrated to the site of myelin oligodendrocyte glycoprotein (MOG) peptide injection and underwent massive expansion. Within six days after EAE induction, bioluminescent ?? T cells were found in the spinal cord and brain, peaking in number between days ten and twelve and then rapidly declining by day fifteen. Reconstitution of ?? T cell?/? mice with ?? T cells derived from ?2-integrin-deficient mice (CD11a, -b or -c) demonstrated that ?? T cell trafficking to the CNS during EAE is independent of this family of adhesion molecules. We also examined the role of ?? T cell-produced IFN-? and TNF-? in EAE and found that production of both cytokines by ?? T cells was required for full development of EAE. These results indicate that ?? T cells are critical for the development of EAE and suggest a therapeutic target in demyelinating disease. PMID:19384874

  6. The metabolic life and times of a T-cell

    PubMed Central

    Michalek, Ryan D.; Rathmell, Jeffrey C.

    2010-01-01

    Summary The regulation of lymphocyte homeostasis is critical for the development and formation of productive immune responses. Cell numbers must be maintained to allow sufficient numbers of lymphocytes to combat foreign pathogens but prevent the accumulation of excess lymphocytes that may increase the risk of developing autoimmunity or neoplasia. Cell extrinsic growth factors are essential to maintain homeostasis and cell survival, and it has become increasingly apparent that a key mechanism of this control is through regulation of cell metabolism. The metabolic state of T cells can have profound influences on cell growth and survival and even differentiation. In particular, resting T cells utilize an energy efficient oxidative metabolism but shift to a highly glycolytic metabolism when stimulated to grow and proliferate by pathogen encounter. After antigen clearance, T cells must return to a more quiescent oxidative metabolism to support T-cell memory. This review highlights how these metabolic changes may be intricately involved with both T-cell growth and death in the control of homeostasis and immunity. PMID:20636818

  7. T Cell Transcriptomes Describe Patient Subtypes in Systemic Lupus Erythematosus

    PubMed Central

    Bradley, Sean J.; Suarez-Fueyo, Abel; Moss, David R.; Kyttaris, Vasileios C.; Tsokos, George C.

    2015-01-01

    Background T cells regulate the adaptive immune response and have altered function in autoimmunity. Systemic Lupus Erythematosus (SLE) has great diversity of presentation and treatment response. Peripheral blood component gene expression affords an efficient platform to investigate SLE immune dysfunction and help guide diagnostic biomarker development for patient stratification. Methods Gene expression in peripheral blood T cell samples for 14 SLE patients and 4 controls was analyzed by high depth sequencing. Unbiased clustering of genes and samples revealed novel patterns related to disease etiology. Functional annotation of these genes highlights pathways and protein domains involved in SLE manifestation. Results We found transcripts for hundreds of genes consistently altered in SLE T cell samples, for which DAVID analysis highlights induction of pathways related to mitochondria, nucleotide metabolism and DNA replication. Fewer genes had reduced mRNA expression, and these were linked to signaling, splicing and transcriptional activity. Gene signatures associated with the presence of dsDNA antibodies, low complement levels and nephritis were detected. T cell gene expression also indicates the presence of several patient subtypes, such as having only a minimal expression phenotype, male type, or severe with or without induction of genes related to membrane protein production. Conclusions Unbiased transcriptome analysis of a peripheral blood component provides insight on autoimmune pathophysiology and patient variability. We present an open source workflow and richly annotated dataset to support investigation of T cell biology, develop biomarkers for patient stratification and perhaps help indicate a source of SLE immune dysfunction. PMID:26544975

  8. CD19-redirected chimeric antigen receptor-modified T cells: a promising immunotherapy for children and adults with B-cell acute lymphoblastic leukemia (ALL).

    PubMed

    Tasian, Sarah K; Gardner, Rebecca A

    2015-10-01

    Relapsed and chemotherapy-refractory B-cell acute lymphoblastic leukemia (B-ALL) remain significant causes of cancer-associated morbidity and mortality for children and adults. Development of new molecularly targeted treatment strategies for patients with high-risk B-ALL is thus a major preclinical and clinical priority. Adoptive cellular therapy with patient-derived human T cells genetically engineered to express CD19 redirected chimeric antigen receptors (CD19 CAR T cells) is one immunotherapeutic modality that has recently demonstrated remarkable efficacy in re-inducing remission in patients with multiply relapsed B-ALL. Investigative teams at several major cancer centers are currently conducting phase I clinical trials in children and/or adults with relapsed/refractory B-ALL to assess the safety and to identify the maximally tolerated dose of each group's CD19 CAR T-cell product. All groups have reported major clinical toxicities associated with CD19 CAR T-cell treatment, including cytokine release syndrome (CRS) and macrophage activation syndrome, neurologic dysfunction and aplasia of normal B lymphocytes, while CD19 CAR T cells persist in vivo. Toxicities have generally been transient or manageable with supportive care measures. Some patients with life-threatening CD19 CAR T-cell induced sequelae have received anti-cytokine receptor antibody treatment to diminish CRS symptoms and/or corticosteroids to terminate CAR T-cell proliferation. Remarkably, 67-90% of children and adults with B-ALL treated with CD19 CAR T cells in these trials have achieved morphologic leukemia remission with many patients also in molecular remission. The duration of CD19 CAR T cell persistence in vivo has varied appreciably among treated patients and likely reflects differences in the CD19 CAR constructs utilized at each institution. CD19-positive and CD19-negative B-ALL relapses after CD19 CAR T-cell treatment have occurred in some patients. Phase II trials to assess the efficacy of CD19 CAR T-cell immunotherapy in larger cohorts of patients with relapsed/refractory B-ALL are ongoing or planned. PMID:26425336

  9. CD19-redirected chimeric antigen receptor-modified T cells: a promising immunotherapy for children and adults with B-cell acute lymphoblastic leukemia (ALL)

    PubMed Central

    Gardner, Rebecca A.

    2015-01-01

    Relapsed and chemotherapy-refractory B-cell acute lymphoblastic leukemia (B-ALL) remain significant causes of cancer-associated morbidity and mortality for children and adults. Development of new molecularly targeted treatment strategies for patients with high-risk B-ALL is thus a major preclinical and clinical priority. Adoptive cellular therapy with patient-derived human T cells genetically engineered to express CD19 redirected chimeric antigen receptors (CD19 CAR T cells) is one immunotherapeutic modality that has recently demonstrated remarkable efficacy in re-inducing remission in patients with multiply relapsed B-ALL. Investigative teams at several major cancer centers are currently conducting phase I clinical trials in children and/or adults with relapsed/refractory B-ALL to assess the safety and to identify the maximally tolerated dose of each group’s CD19 CAR T-cell product. All groups have reported major clinical toxicities associated with CD19 CAR T-cell treatment, including cytokine release syndrome (CRS) and macrophage activation syndrome, neurologic dysfunction and aplasia of normal B lymphocytes, while CD19 CAR T cells persist in vivo. Toxicities have generally been transient or manageable with supportive care measures. Some patients with life-threatening CD19 CAR T-cell induced sequelae have received anti-cytokine receptor antibody treatment to diminish CRS symptoms and/or corticosteroids to terminate CAR T-cell proliferation. Remarkably, 67–90% of children and adults with B-ALL treated with CD19 CAR T cells in these trials have achieved morphologic leukemia remission with many patients also in molecular remission. The duration of CD19 CAR T cell persistence in vivo has varied appreciably among treated patients and likely reflects differences in the CD19 CAR constructs utilized at each institution. CD19-positive and CD19-negative B-ALL relapses after CD19 CAR T-cell treatment have occurred in some patients. Phase II trials to assess the efficacy of CD19 CAR T-cell immunotherapy in larger cohorts of patients with relapsed/refractory B-ALL are ongoing or planned. PMID:26425336

  10. Regulatory T cells and intestinal homeostasis.

    PubMed

    Coombes, Janine L; Robinson, Nicholas J; Maloy, Kevin J; Uhlig, Holm H; Powrie, Fiona

    2005-04-01

    Murine models of inflammatory bowel disease (IBD) are useful tools for the study of the pathogenesis and regulation of intestinal inflammation. Colitis can be induced in immune-deficient mice following transfer of populations of T cells or following infection with Helicobacter hepaticus and other intestinal pathogens. In these situations, colitis occurs as a result of the absence of a specialized population of regulatory cells, as transfer of CD4(+)CD25(+) T cells prevents disease. Importantly, from a clinical perspective, CD4(+)CD25(+) T cells can also reverse an established colitis. CD4(+)CD25(+) T cells proliferate both in the secondary lymphoid organs and at the site of inflammation, suggesting that regulation occurs both locally and systemically. CD4(+)CD25(+) T cells are not only capable of regulating other T cells but are also capable of suppressing components of the innate immune system. Control of colitis is dependent on the presence of the immunosuppressive cytokines interleukin-10 and transforming growth factor-beta, although their roles are divergent and complex. Regulatory T cells represent one of the host's mechanisms to prevent immune pathology during chronic immune stimulation. Enhancement of regulatory T-cell activity may be useful to control autoreactive T-cell responses and inhibit harmful inflammatory diseases such as asthma and IBD. PMID:15790359

  11. Bim/Bcl-2 balance is critical for maintaining naive and memory T cell homeostasis

    PubMed Central

    Wojciechowski, Sara; Tripathi, Pulak; Bourdeau, Tristan; Acero, Luis; Grimes, H. Leighton; Katz, Jonathan D.; Finkelman, Fred D.; Hildeman, David A.

    2007-01-01

    We examined the role of the antiapoptotic molecule Bcl-2 in combating the proapoptotic molecule Bim in control of naive and memory T cell homeostasis using Bcl-2?/? mice that were additionally deficient in one or both alleles of Bim. Naive T cells were significantly decreased in Bim+/?Bcl-2?/? mice, but were largely restored in Bim?/?Bcl-2?/? mice. Similarly, a synthetic Bcl-2 inhibitor killed wild-type, but not Bim?/?, T cells. Further, T cells from Bim+/?Bcl-2?/? mice died rapidly ex vivo and were refractory to cytokine-driven survival in vitro. In vivo, naive CD8+ T cells required Bcl-2 to combat Bim to maintain peripheral survival, whereas naive CD4+ T cells did not. In contrast, Bim+/?Bcl-2?/? mice generated relatively normal numbers of memory T cells after lymphocytic choriomeningitis virus infection. Accumulation of memory T cells in Bim+/?Bcl-2?/? mice was likely caused by their increased proliferative renewal because of the lymphopenic environment of the mice. Collectively, these data demonstrate a critical role for a balance between Bim and Bcl-2 in controlling homeostasis of naive and memory T cells. PMID:17591857

  12. ATP-dependent chromatin remodeling in T cells

    PubMed Central

    Wurster, Andrea L.; Pazin, Michael J.

    2012-01-01

    One of the best studied systems for mammalian chromatin remodeling is transcriptional regulation during T cell development. The variety of these studies have led to important findings in T cell gene regulation and cell fate determination. Importantly, these findings have also advanced our knowledge of the function of remodeling enzymes in mammalian gene regulation. In this review, first we briefly present biochemical/cell-free analysis of 3 types of ATP dependent remodeling enzymes (SWI/SNF, Mi2, and ISWI), to construct an intellectual framework to understand how these enzymes might be working. Second, we compare and contrast the function of these enzymes, during early (thymic) and late (peripheral) T cell development. Finally, we examine some of the gaps in our present understanding. PMID:21999456

  13. Morphological development of rip channel systems: Normal and near-normal wave incidence

    NASA Astrophysics Data System (ADS)

    Calvete, D.; Dodd, N.; FalquéS, A.; van Leeuwen, S. M.

    2005-10-01

    The process of formation of a rip channel/crescentic bar system on a straight, sandy coast is examined. A short review of earlier studies is presented. A morphodynamic stability model is then formulated. The resulting model includes a comprehensive treatment of shoaling and surf zone hydrodynamics, including wave refraction on depth and currents and waves. The sediment transport is modeled using a total load formula. This model is used to study the formation of rip currents and channels on a straight single-barred coast. It is found that this more comprehensive treatment of the dynamics reveals the basic rip cells predicted in earlier studies for normal incidence. Also as before, cell spacings (?) scale with shore-to-bar crest distance (Xb), while growth rates decrease. The ? increases with offshore wave height (H) up to a saturation value; increasing H also increases instability. Experiments at off-normal wave incidence (? > 0) introduce obliquity into the evolving bed forms, as expected, and ? increases approximately linearly. the e-folding times also increase with ?. At normal incidence, ? increases weakly with wave period, but at oblique angles, ? decreases. Tests also reveal the presence of forced circulation cells nearer to the shoreline, which carve out bed forms there. The dynamics of these forced cells is illustrated and discussed along with the associated shoreline perturbation. Transverse bars are also discovered. Their dynamics are discussed. Model predictions are also compared with field observations. The relevance of the present approach to predictions of fully developed beach states is also discussed.

  14. The mutational landscape of cutaneous T cell lymphoma and Sézary syndrome.

    PubMed

    da Silva Almeida, Ana Carolina; Abate, Francesco; Khiabanian, Hossein; Martinez-Escala, Estela; Guitart, Joan; Tensen, Cornelis P; Vermeer, Maarten H; Rabadan, Raul; Ferrando, Adolfo; Palomero, Teresa

    2015-12-01

    Sézary syndrome is a leukemic and aggressive form of cutaneous T cell lymphoma (CTCL) resulting from the malignant transformation of skin-homing central memory CD4(+) T cells. Here we performed whole-exome sequencing of tumor-normal sample pairs from 25 patients with Sézary syndrome and 17 patients with other CTCLs. These analyses identified a distinctive pattern of somatic copy number alterations in Sézary syndrome, including highly prevalent chromosomal deletions involving the TP53, RB1, PTEN, DNMT3A and CDKN1B tumor suppressors. Mutation analysis identified a broad spectrum of somatic mutations in key genes involved in epigenetic regulation (TET2, CREBBP, KMT2D (MLL2), KMT2C (MLL3), BRD9, SMARCA4 and CHD3) and signaling, including MAPK1, BRAF, CARD11 and PRKG1 mutations driving increased MAPK, NF-?B and NFAT activity upon T cell receptor stimulation. Collectively, our findings provide new insights into the genetics of Sézary syndrome and CTCL and support the development of personalized therapies targeting key oncogenically activated signaling pathways for the treatment of these diseases. PMID:26551667

  15. Cd81 Interacts with the T Cell Receptor to Suppress Signaling

    PubMed Central

    Cevik, Safak Isil; Keskin, Nazli; Belkaya, Serkan; Ozlu, Meral Ilcim; Deniz, Emre; Tazebay, Uygar Halis; Erman, Batu

    2012-01-01

    CD81 (TAPA-1) is a ubiquitously expressed tetraspanin protein identified as a component of the B lymphocyte receptor (BCR) and as a receptor for the Hepatitis C Virus. In an effort to identify trans-membrane proteins that interact with the T-cell antigen receptor (TCR), we performed a membrane yeast two hybrid screen and identified CD81 as an interactor of the CD3delta subunit of the TCR. We found that in the absence of CD81, in thymocytes from knockout mice, TCR engagement resulted in stronger signals. These results were recapitulated in T cell lines that express low levels of CD81 through shRNA mediated silencing. Increased signaling did not result from alterations in the levels of TCR on the surface of T lymphocytes. Although CD81 is not essential for normal T lymphocyte development, it plays an important role in regulating TCR and possibly pre-TCR signal transduction by controlling the strength of signaling. CD81 dependent alterations in thymocyte signaling are evident in increased CD5 expression on CD81 deficient double positive (DP) thymocytes. We conclude that CD81 interacts with the T cell receptor to suppress signaling. PMID:23226274

  16. T-cell-immunity-based inhibitory effects of orally administered herbal medicine juzen-taiho-to on the growth of primarily developed melanocytic tumors in RET-transgenic mice.

    PubMed

    Dai, Y; Kato, M; Takeda, K; Kawamoto, Y; Akhand, A A; Hossain, K; Suzuki, H; Nakashima, I

    2001-09-01

    We examined the effect of oral administration of juzen-taiho-to, one of the most popular herbal medicines in Japan, on primary melanocytic tumor growth in RET-transgenic mice. There was virtually no difference between the lengths of tumor-free stages in the juzen-taiho-to-treated mice and the untreated littermate control mice. The rate of tumor growth in the juzen-taiho-to-treated mice, however, was greatly suppressed during the entire period after the initial tumor development. Correspondingly, the life span of juzen-taiho-to-treated transgenic mice was longer (over 6 mo in mean value) than that of control mice. We partially elucidated the mechanism of the antitumor effect of juzen-taiho-to. The addition of juzen-taiho-to at any of a wide range (50-1600 microg per ml) of concentrations to in vitro cultures of Mel-Ret cells, a malignant melanoma cell line derived from a RET-transgenic mouse, caused neither cell death nor cell cycle arrest directly. The addition of 50-400 microg per ml of juzen-taiho-to to cultures of murine spleen cells, however, promoted their DNA synthesis. More importantly, peritoneal exudate cells from the juzen-taiho-to-treated transgenic mice, in which the ratio and number of T cells were increased, displayed an antitumor immunity against Mel-Ret cells in vitro. Interestingly, the peritoneal-exudate-cell-associated antitumor immunity was further augmented by the addition of 200-400 microg per ml of juzen-taiho-to in vitro. This immunity, which was primarily conveyed by Thy-1+ T cells, was antigen (RET/melanoma) specific and cytotoxic. Amongst various chemical ingredients of juzen-taiho-to examined in this study, glycirrhizin displayed an action, partially replacing that of juzen-taiho-to, in promoting anti-Mel-Ret immunity when supplementarily added in vitro. These results suggest that juzen-taiho-to suppresses once-developed primary melanocytic tumors through potentiation of T-cell-mediated antitumor cytotoxic immunity in vivo. PMID:11564179

  17. Role of Interferon Regulatory Factor 7 in T Cell Responses during Acute Lymphocytic Choriomeningitis Virus Infection

    PubMed Central

    Cerny, Anna M.; Fitzgerald, Katherine A.; Kurt-Jones, Evelyn A.; Finberg, Robert W.

    2012-01-01

    Type I interferons (IFNs), predominantly IFN-? and -?, play critical roles in both innate and adaptive immune responses against viral infections. Interferon regulatory factor 7 (IRF7), a key innate immune molecule in the type I IFN signaling pathway, is essential for the type I IFN response to many viruses, including lymphocytic choriomeningitis virus (LCMV). Here, we show that although IRF7 knockout (KO) mice failed to control the replication of LCMV in the early stages of infection, they were capable of clearing LCMV infection. Despite the lack of type I IFN production, IRF7 KO mice generated normal CD4+ T cell responses, and the expansion of naïve CD8+ T cells into primary CD8+ T cells specific for LCMV GP33–41 was relatively normal. In contrast, the expansion of the LCMV NP396-specific CD8+ T cells was severely impaired in IRF7 KO mice. We demonstrated that this defective CD8+ T cell response is due neither to an impaired antigen-presenting system nor to any intrinsic role of IRF7 in CD8+ T cells. The lack of a type I IFN response in IRF7 KO mice did not affect the formation of memory CD8+ T cells. Thus, the present study provides new insight into the impact of the innate immune system on viral pathogenesis and demonstrates the critical contribution of innate immunity in controlling virus replication in the early stages of infection, which may shape the quality of CD8+ T cell responses. PMID:22875973

  18. Regulatory T Cells Modulate DNA Vaccine Immunogenicity at Early Time via Functional CD4+ T Cells and Antigen Duration

    PubMed Central

    Qin, Lizeng; Jiang, Guosheng; Han, Jinxiang; Letvin, Norman L.

    2015-01-01

    The development of an effective vaccine against HIV has proved to be difficult. Many factors including natural regulatory T cells (Treg cells) can dampen the CD8 T-cell immunogenicity. In this study, we aimed to understand how Treg cells control CD8+ T-cell immune responses during DNA prime-boost immunization. Animals were immunized with plasmid HIV IIIB gp120 DNA following elimination of Treg cells by administration of anti-CD25 neutralizing antibody. Results demonstrated that the pool size of CD4+ T cells producing both IL-2 and/or IFN-? (CD4+/IL-2+/IFN-?+) was increased solely during the priming phase. An increment of tetramer binding and intracellular cytokine IFN-? expression, however, were elevated in both primary and secondary stages in CD8+ T cells. The speed of antigen clearance was also investigated by using DNA luciferase. Surprisingly, DNA luciferase expression was declined to basal level over the ensuing observation period when Treg cells were depleted. Importantly, we found for the first time that DNA expression pattern in Treg-depleted animals was similar to that of the regular memory phase. Moreover, in mice that were exposed to antigen over 5?days prior to Treg cell depletion, CD8+ T-cell memory response was not affected. Thus, in the present study, we propose a new concept and prove that the enhanced immune response following the depletion of Treg cells during the priming phase likely adds one more set of memory response to the immune system. Taken together, our findings support the notion that Treg cells control DNA vaccine immunogenicity at an early time via antigen duration and functional CD4+ T-cell responses. PMID:26483796

  19. Reduced TET2 function leads to T-cell lymphoma with follicular helper T-cell-like features in mice

    PubMed Central

    Muto, H; Sakata-Yanagimoto, M; Nagae, G; Shiozawa, Y; Miyake, Y; Yoshida, K; Enami, T; Kamada, Y; Kato, T; Uchida, K; Nanmoku, T; Obara, N; Suzukawa, K; Sanada, M; Nakamura, N; Aburatani, H; Ogawa, S; Chiba, S

    2014-01-01

    TET2 (Ten Eleven Translocation 2) is a dioxygenase that converts methylcytosine (mC) to hydroxymethylcytosine (hmC). TET2 loss-of-function mutations are highly frequent in subtypes of T-cell lymphoma that harbor follicular helper T (Tfh)-cell-like features, such as angioimmunoblastic T-cell lymphoma (30–83%) or peripheral T-cell lymphoma, not otherwise specified (10–49%), as well as myeloid malignancies. Here, we show that middle-aged Tet2 knockdown (Tet2gt/gt) mice exhibit Tfh-like cell overproduction in the spleen compared with control mice. The Tet2 knockdown mice eventually develop T-cell lymphoma with Tfh-like features after a long latency (median 67 weeks). Transcriptome analysis revealed that these lymphoma cells had Tfh-like gene expression patterns when compared with splenic CD4-positive cells of wild-type mice. The lymphoma cells showed lower hmC densities around the transcription start site (TSS) and higher mC densities at the regions of the TSS, gene body and CpG islands. These epigenetic changes, seen in Tet2 insufficiency-triggered lymphoma, possibly contributed to predated outgrowth of Tfh-like cells and subsequent lymphomagenesis. The mouse model described here suggests that TET2 mutations play a major role in the development of T-cell lymphoma with Tfh-like features in humans. PMID:25501021

  20. Harnessing the Heterogeneity of T Cell Differentiation Fate to Fine-Tune Generation of Effector and Memory T Cells

    PubMed Central

    Gong, Chang; Linderman, Jennifer J.; Kirschner, Denise

    2014-01-01

    Recent studies show that naïve T cells bearing identical T cell receptors experience heterogeneous differentiation and clonal expansion processes. The factors controlling this outcome are not well characterized, and their contributions to immune cell dynamics are similarly poorly understood. In this study, we develop a computational model to elaborate mechanisms occurring within and between two important physiological compartments, lymph nodes and blood, to determine how immune cell dynamics are controlled. Our multi-organ (multi-compartment) model integrates cellular and tissue level events and allows us to examine the heterogeneous differentiation of individual precursor cognate naïve T cells to generate both effector and memory T lymphocytes. Using this model, we simulate a hypothetical immune response and reproduce both primary and recall responses to infection. Increased numbers of antigen-bearing dendritic cells (DCs) are predicted to raise production of both effector and memory T cells, and distinct “sweet spots” of peptide-MHC levels on those DCs exist that favor CD4+ or CD8+ T cell differentiation toward either effector or memory cell phenotypes. This has important implications for vaccine development and immunotherapy. PMID:24600448

  1. T Cells: Soldiers and Spies-The Surveillance and Control of Effector T Cells by Regulatory T Cells.

    PubMed

    Hall, Bruce M

    2015-11-01

    Traditionally, T cells were CD4(+) helper or CD8(+) cytotoxic T cells, and with antibodies, they were the soldiers of immunity. Now, many functionally distinct subsets of activated CD4(+) and CD8(+) T cells have been described, each with distinct cytokine and transcription factor expression. For CD4(+) T cells, these include Th1 cells expressing the transcription factor T-bet and cytokines IL-2, IFN-?, and TNF-?; Th2 cells expressing GATA-3 and the cytokines IL-4, IL-5, and IL-13; and Th17 cells expressing ROR?t and cytokines IL-17A, IL-17F, IL-21, and IL-22. The cytokines produced determine the immune inflammation that they mediate. T cells of the effector lineage can be naïve T cells, recently activated T cells, or memory T cells that can be distinguished by cell surface markers. T regulatory cells or spies were characterized as CD8(+) T cells expressing I-J in the 1970s. In the 1980s, suppressor cells fell into disrepute when the gene for I-J was not present in the mouse MHC I region. At that time, a CD4(+) T cell expressing CD25, the IL-2 receptor-?, was identified to transfer transplant tolerance. This was the same phenotype of activated CD4(+)CD25(+) T cells that mediated rejection. Thus, the cells that could induce tolerance and undermine rejection had similar badges and uniforms as the cells effecting rejection. Later, FOXP3, a transcription factor that confers suppressor function, was described and distinguishes T regulatory cells from effector T cells. Many subtypes of T regulatory cells can be characterized by different expressions of cytokines and receptors for cytokines or chemokines. In intense immune inflammation, T regulatory cells express cytokines characteristic of effector cells; for example, Th1-like T regulatory cells express T-bet, and IFN-?-like Th1 cells and effector T cells can change sides by converting to T regulatory cells. Effector T cells and T regulatory cells use similar molecules to be activated and mediate their function, and thus, it can be very difficult to distinguish soldiers from spies. PMID:25876770

  2. T Cells: Soldiers and Spies—The Surveillance and Control of Effector T Cells by Regulatory T Cells

    PubMed Central

    2015-01-01

    Traditionally, T cells were CD4+ helper or CD8+ cytotoxic T cells, and with antibodies, they were the soldiers of immunity. Now, many functionally distinct subsets of activated CD4+ and CD8+ T cells have been described, each with distinct cytokine and transcription factor expression. For CD4+ T cells, these include Th1 cells expressing the transcription factor T-bet and cytokines IL-2, IFN-?, and TNF-?; Th2 cells expressing GATA-3 and the cytokines IL-4, IL-5, and IL-13; and Th17 cells expressing ROR?t and cytokines IL-17A, IL-17F, IL-21, and IL-22. The cytokines produced determine the immune inflammation that they mediate. T cells of the effector lineage can be naïve T cells, recently activated T cells, or memory T cells that can be distinguished by cell surface markers. T regulatory cells or spies were characterized as CD8+ T cells expressing I-J in the 1970s. In the 1980s, suppressor cells fell into disrepute when the gene for I-J was not present in the mouse MHC I region. At that time, a CD4+ T cell expressing CD25, the IL-2 receptor-?, was identified to transfer transplant tolerance. This was the same phenotype of activated CD4+CD25+ T cells that mediated rejection. Thus, the cells that could induce tolerance and undermine rejection had similar badges and uniforms as the cells effecting rejection. Later, FOXP3, a transcription factor that confers suppressor function, was described and distinguishes T regulatory cells from effector T cells. Many subtypes of T regulatory cells can be characterized by different expressions of cytokines and receptors for cytokines or chemokines. In intense immune inflammation, T regulatory cells express cytokines characteristic of effector cells; for example, Th1-like T regulatory cells express T-bet, and IFN-?–like Th1 cells and effector T cells can change sides by converting to T regulatory cells. Effector T cells and T regulatory cells use similar molecules to be activated and mediate their function, and thus, it can be very difficult to distinguish soldiers from spies. PMID:25876770

  3. Induction of IL-17 and nonclassical T-cell activation by HIV-Tat protein

    PubMed Central

    Johnson, Tory P.; Patel, Karan; Johnson, Kory R.; Maric, Dragan; Calabresi, Peter A.; Hasbun, Rodrigo; Nath, Avindra

    2013-01-01

    Chronic immune activation is a major complication of antiretroviral therapy (ART) for HIV infection and can cause a devastating immune reconstitution inflammatory syndrome (IRIS) in the brain. The mechanism of T-cell activation in this population is not well understood. We found HIV-Tat protein and IL-17–expressing mononuclear cells in the brain of an individual with IRIS. Tat was also present in the CSF of individuals virologically controlled on ART. Hence we examined if Tat protein could directly activate T cells. Tat transcriptionally dysregulated 94 genes and induced secretion of 11 cytokines particularly activation of IL-17 signaling pathways supporting the development of a proinflammatory state. Tat increased IL-17 transcription and secretion in T cells. Tat entered the T cells rapidly by clathrin-mediated endocytosis and localized to both the cytoplasm and the nucleus. Tat activated T cells through a nonclassical pathway dependent upon vascular endothelial growth factor receptor-2 and downstream secondary signaling pathways but independent of the T-cell receptor. However, Tat stimulation of T cells did not induce T-cell proliferation but increased viral infectivity. This study demonstrates Tat’s role as a virulence factor, by driving T-cell activation and contributing to IRIS pathophysiology. This supports the necessity of an anti-Tat therapy in conjunction with ART and identifies multiple targetable pathways to prevent Tat-mediated T-cell activation. PMID:23898208

  4. Laboratory Simulation of Shear Band Development in Growth Normal Fault

    NASA Astrophysics Data System (ADS)

    Chu, Sheng-Shin; Lin, Ming-Lang

    2013-04-01

    According to the studies about active faults in metropolitan Taipei area, it has been indicated that Shanchiao Fault at the western rim of Taipei Basin is a highly active normal fault. Slip of the fault can cause deformation of shallower soil layers and lead to the destruction of infrastructures, residential building foundations and utility lines near the influenced area. It was interpreted that Shanchiao Fault is a growth normal fault based on geological drilling and dating information. Therefore in this study, a geological structure similar to growth normal fault (such as Shanchiao Fault) was constructed to simulate the slip induced ground deformation after an additional layer of sedimentation formed above the deformed normal fault. In this study, a sand box under gravity condition was formulated with non-cohesive sands in order to investigate the propagation of shear bands and surface deformation of a growth normal fault. With the presence of sedimentation layer on top of the deformed soil layer due to normal fault, the shear band developed along the previous shear band and propagated upward to the sand surface with a much faster speed comparing to the case when there is no sedimentation layer (i.e. normal fault only). The offset ratio of 1.3~1.5% (defines as the fault tip offset displacement over the thickness of soil layer) for this particular growth fault simulation is required in order to develop a shear band toward the ground surface. Based on the test results, it is concluded that if there is any seismic activity of Shanchiao Fault, with a smaller offset displacement from the fault tip, although the depositional thickness of the upper layer is very thick, the shear band could still be propagated to the ground surface and cause severe damages to the important facilities and infrastructure with Taipei Basin. Therefore, seismic design integrated with the knowledge of near-ground deformation characteristics due to this type of fault need to be emphasized in current building codes, especially for critical facilities such as the nuclear power plant. Key words: Shanchiao Fault, Growth Normal Fault, Sand Box Test, Shear Band, Offset Ratio

  5. Genetically modified T cells in cancer therapy: opportunities and challenges.

    PubMed

    Sharpe, Michaela; Mount, Natalie

    2015-04-01

    Tumours use many strategies to evade the host immune response, including downregulation or weak immunogenicity of target antigens and creation of an immune-suppressive tumour environment. T cells play a key role in cell-mediated immunity and, recently, strategies to genetically modify T cells either through altering the specificity of the T cell receptor (TCR) or through introducing antibody-like recognition in chimeric antigen receptors (CARs) have made substantial advances. The potential of these approaches has been demonstrated in particular by the successful use of genetically modified T cells to treat B cell haematological malignancies in clinical trials. This clinical success is reflected in the growing number of strategic partnerships in this area that have attracted a high level of investment and involve large pharmaceutical organisations. Although our understanding of the factors that influence the safety and efficacy of these therapies has increased, challenges for bringing genetically modified T-cell immunotherapy to many patients with different tumour types remain. These challenges range from the selection of antigen targets and dealing with regulatory and safety issues to successfully navigating the routes to commercial development. However, the encouraging clinical data, the progress in the scientific understanding of tumour immunology and the improvements in the manufacture of cell products are all advancing the clinical translation of these important cellular immunotherapies. PMID:26035842

  6. Romidepsin targets multiple survival signaling pathways in malignant T cells

    PubMed Central

    Valdez, B C; Brammer, J E; Li, Y; Murray, D; Liu, Y; Hosing, C; Nieto, Y; Champlin, R E; Andersson, B S

    2015-01-01

    Romidepsin is a cyclic molecule that inhibits histone deacetylases. It is Food and Drug Administration-approved for treatment of cutaneous and peripheral T-cell lymphoma, but its precise mechanism of action against malignant T cells is unknown. To better understand the biological effects of romidepsin in these cells, we exposed PEER and SUPT1 T-cell lines, and a primary sample from T-cell lymphoma patient (Patient J) to romidepsin. We then examined the consequences in some key oncogenic signaling pathways. Romidepsin displayed IC50 values of 10.8, 7.9 and 7.0?nm in PEER, SUPT1 and Patient J cells, respectively. Strong inhibition of histone deacetylases and demethylases, increased production of reactive oxygen species and decreased mitochondrial membrane potential were observed, which may contribute to the observed DNA-damage response and apoptosis. The stress-activated protein kinase/c-Jun N-terminal kinase signaling pathway and unfolded protein response in the endoplasmic reticulum were activated, whereas the phosphatidylinositol 3-kinase/AKT/mammalian target of rapamycin (PI3K/AKT/mTOR) and ?-catenin pro-survival pathways were inhibited. The decreased level of ?-catenin correlated with the upregulation of its inhibitor SFRP1 through romidepsin-mediated hypomethylation of its gene promoter. Our results provide new insights into how romidepsin invokes malignant T-cell killing, show evidence of its associated DNA hypomethylating activity and offer a rationale for the development of romidepsin-containing combination therapies. PMID:26473529

  7. Genetically modified T cells in cancer therapy: opportunities and challenges

    PubMed Central

    Sharpe, Michaela; Mount, Natalie

    2015-01-01

    Tumours use many strategies to evade the host immune response, including downregulation or weak immunogenicity of target antigens and creation of an immune-suppressive tumour environment. T cells play a key role in cell-mediated immunity and, recently, strategies to genetically modify T cells either through altering the specificity of the T cell receptor (TCR) or through introducing antibody-like recognition in chimeric antigen receptors (CARs) have made substantial advances. The potential of these approaches has been demonstrated in particular by the successful use of genetically modified T cells to treat B cell haematological malignancies in clinical trials. This clinical success is reflected in the growing number of strategic partnerships in this area that have attracted a high level of investment and involve large pharmaceutical organisations. Although our understanding of the factors that influence the safety and efficacy of these therapies has increased, challenges for bringing genetically modified T-cell immunotherapy to many patients with different tumour types remain. These challenges range from the selection of antigen targets and dealing with regulatory and safety issues to successfully navigating the routes to commercial development. However, the encouraging clinical data, the progress in the scientific understanding of tumour immunology and the improvements in the manufacture of cell products are all advancing the clinical translation of these important cellular immunotherapies. PMID:26035842

  8. Annexin-1 modulates T-cell activation and differentiation.

    PubMed

    D'Acquisto, Fulvio; Merghani, Ahmed; Lecona, Emilio; Rosignoli, Guglielmo; Raza, Karim; Buckley, Christopher D; Flower, Roderick J; Perretti, Mauro

    2007-02-01

    Annexin-1 is an anti-inflammatory protein that plays an important homeostatic role in innate immunity; however, its potential actions in the modulation of adaptive immunity have never been explored. Although inactive by itself, addition of annexin-1 to stimulated T cells augmented anti-CD3/CD28-mediated CD25 and CD69 expression and cell proliferation. This effect was paralleled by increased nuclear factor-kappaB (NF-kappaB), nuclear factor of activated T cells (NFATs), and activator protein-1 (AP-1) activation and preceded by a rapid T-cell receptor (TCR)-induced externalization of the annexin-1 receptor. Interestingly, differentiation of naive T cells in the presence of annexin-1 increased skewing in Th1 cells; in the collagen-induced arthritis model, treatment of mice with annexin-1 during the immunization phase exacerbated signs and symptoms at disease onset. Consistent with these findings, blood CD4+ cells from patients with rheumatoid arthritis showed a marked up-regulation of annexin-1 expression. Together these results demonstrate that annexin-1 is a molecular "tuner" of TCR signaling and suggest this protein might represent a new target for the development of drugs directed to pathologies where an unbalanced Th1/Th2 response or an aberrant activation of T cells is the major etiologic factor. PMID:17008549

  9. Towards immunotherapy with redirected T cells in a large animal model: Ex vivo activation, expansion, and genetic modification of canine T cells

    PubMed Central

    Mata, Melinda; Vera, Juan; Gerken, Claudia; Rooney, Cliona M.; Miller, Tasha; Pfent, Catherine; Wang, Lisa L.; Wilson-Robles, Heather M.; Gottschalk, Stephen

    2014-01-01

    Adoptive transfer of T cells expressing chimeric antigen receptors (CARs) has shown promising anti-tumor activity in early phase clinical studies, especially for hematological malignancies. However, most preclinical models do not reliably mimic human disease. We reasoned that developing an adoptive T-cell therapy approach for spontaneous osteosarcoma (OS) occurring in dogs would more closely reproduce the condition in human cancer. To generate CAR-expressing canine T cells we developed expansion and transduction protocols that allow for the generation of sufficient numbers of CAR-expressing canine T cells for future clinical studies in dogs within 2 weeks of ex vivo culture. To evaluate the functionality of CAR-expressing canine T cells we targeted HER2-positive OS. We demonstrate that canine OS is positive for HER2, and that canine T cells expressing a HER2-specific CAR with human-derived transmembrane and CD28.? signaling domains recognize and kill HER2-positive canine OS cell lines in an antigen-dependent manner. To reduce the potential immunogenicity of the CAR we evaluated a CAR with canine-derived transmembrane and signaling domains, and found no functional difference between human and canine CARs. Hence, we have successfully developed a strategy to generate CAR-expressing canine T cells for future preclinical studies in dogs. Testing T-cell therapies in an immunocompetent, outbred animal model may improve our ability to predict their safety and efficacy prior to conducting studies in humans. PMID:25198528

  10. Trps1 is necessary for normal temporomandibular joint development.

    PubMed

    Michikami, Ikumi; Fukushi, Toshiya; Honma, Shiho; Yoshioka, Seisuke; Itoh, Shunji; Muragaki, Yasuteru; Kurisu, Kojiro; Ooshima, Takashi; Wakisaka, Satoshi; Abe, Makoto

    2012-04-01

    Mutation of the human TRPS1 gene leads to trichorhinophalangeal syndrome (TRPS), which is characterized by an abnormal development of various organs including the craniofacial skeleton. Trps1 has recently been shown to be expressed in the jaw joints of zebrafish; however, whether Trps1 is expressed in the mammalian temporomandibular joint (TMJ), or whether it is necessary for TMJ development is unknown. We have analyzed (1) the expression pattern of Trps1 during TMJ development in mice and (2) TMJ development in Trps1 knockout animals. Trps1 is expressed in the maxillo-mandibular junction at embryonic day (E) 11.5. At E15.5, expression is restricted to the developing condylar cartilage and to the surrounding joint disc progenitor cells. In Trps1 knockout mice, the glenoid fossa of the temporal bone forms relatively normally but the condylar process is extremely small and the joint disc and cavities do not develop. The initiation of condyle formation is slightly delayed in the mutants at E14.5; however, at E18.5, the flattened chondrocyte layer is narrowed and most of the condylar chondrocytes exhibit precocious chondrocyte maturation. Expression of Runx2 and its target genes is expanded toward the condylar apex in the mutants. These observations underscore the indispensable role played by Trps1 in normal TMJ development in supporting the differentiation of disc and synoviocyte progenitor cells and in coordinating condylar chondrocyte differentiation. PMID:22427063

  11. CD4-CD8-?? and ?? T Cells Display Inflammatory and Regulatory Potentials during Human Tuberculosis

    PubMed Central

    Pinheiro, Melina B.; Antonelli, Lis R.; Sathler-Avelar, Renato; Vitelli-Avelar, Danielle M.; Spindola-de-Miranda, Silvana; Guimarães, Tânia M. P. D.; Teixeira-Carvalho, Andrea; Martins-Filho, Olindo A.; Toledo, Vicente P. C. P.

    2012-01-01

    T-cells play an important role controlling immunity against pathogens and therefore influence the outcome of human diseases. Although most T-lymphocytes co-express either CD4 or CD8, a smaller T-cell subset found the in the human peripheral blood that expresses the ?? or ?? T-cell-receptor (TCR) lacks the CD4 and CD8 co-receptors. These double negative (DN) T-cells have been shown to display important immunological functions in human diseases. To better understand the role of DN T-cells in human Mycobacterium tuberculosis, we have characterized their frequency, activation and cytokine profile in a well-defined group of tuberculosis patients, categorized as severe and non-severe based on their clinical status. Our data showed that whereas high frequency of ?? DN T-cells observed in M. tuberculosis-infected patients are associated with disease severity, decreased proportion of ?? DN T-cells are found in patients with severe tuberculosis. Together with activation of CD4+ and CD8+ T-cells, higher frequencies of both ?? and ?? DN T-cells from tuberculosis patients also express the chronic activation marker HLA-DR. However, the expression of CD69, an early activation marker, is selectively observed in DN T-cells. Interestingly, while ?? and ?? DN T-cells from patients with non-severe tuberculosis display a pro-inflammatory cytokine profile, characterized by enhanced IFN-?, the ?? DN T-cells from patients with severe disease express a modulatory profile exemplified by enhanced interleukin-10 production. Overall, our findings suggest that ?? and ?? DN T-cell present disparate immunoregulatory potentials and seems to contribute to the development/maintenance of distinct clinical aspects of TB, as part of the complex immunological network triggered by the TB infection. PMID:23239994

  12. Efficient T-cell priming and activation requires signaling through prostaglandin E2 (EP) receptors.

    PubMed

    Sreeramkumar, Vinatha; Hons, Miroslav; Punzón, Carmen; Stein, Jens V; Sancho, David; Fresno, Manuel; Cuesta, Natalia

    2016-01-01

    Understanding the regulation of T-cell responses during inflammation and auto-immunity is fundamental for designing efficient therapeutic strategies against immune diseases. In this regard, prostaglandin E2 (PGE2) is mostly considered a myeloid-derived immunosuppressive molecule. We describe for the first time that T cells secrete PGE2 during T-cell receptor stimulation. In addition, we show that autocrine PGE2 signaling through EP receptors is essential for optimal CD4(+) T-cell activation in vitro and in vivo, and for T helper 1 (Th1) and regulatory T cell differentiation. PGE2 was found to provide additive co-stimulatory signaling through AKT activation. Intravital multiphoton microscopy showed that triggering EP receptors in T cells is also essential for the stability of T cell-dendritic cell (DC) interactions and Th-cell accumulation in draining lymph nodes (LNs) during inflammation. We further demonstrated that blocking EP receptors in T cells during the initial phase of collagen-induced arthritis in mice resulted in a reduction of clinical arthritis. This could be attributable to defective T-cell activation, accompanied by a decline in activated and interferon-?-producing CD4(+) Th1 cells in draining LNs. In conclusion, we prove that T lymphocytes secret picomolar concentrations of PGE2, which in turn provide additive co-stimulatory signaling, enabling T cells to attain a favorable activation threshold. PGE2 signaling in T cells is also required for maintaining long and stable interactions with DCs within LNs. Blockade of EP receptors in vivo impairs T-cell activation and development of T cell-mediated inflammatory responses. This may have implications in various pathophysiological settings. PMID:26051593

  13. Primary Cytomegalovirus Infection Significantly Impacts Circulating T Cells in Kidney Transplant Recipients.

    PubMed

    Meijers, R W J; Litjens, N H R; Hesselink, D A; Langerak, A W; Baan, C C; Betjes, M G H

    2015-12-01

    Cytomegalovirus (CMV) infection profoundly affects the T cell compartment and is associated with alterations in T cell aging parameters and generation of cytotoxic CD4(+) CD28null T cells. Hence, the effect of a primary CMV infection post-kidney transplantation (KT) on the peripheral T cell compartment was examined. As aging parameters, we determined the T cell differentiation status, T cell receptor excision circle (TREC) content, CD31(+) naïve T cell numbers and relative telomere length (RTL) pre-KT and 12 months post-KT. CMV-seronegative KT recipients, receiving a kidney from a CMV-seropositive donor (D+/R-) were compared to D+/R+ KT recipients. Eleven out of the 22 D+/R- KT recipients had CMV viremia post-KT. They developed CMV-specific CD4(+) and CD8(+) T cells and their T cell compartment shifted towards a more differentiated memory phenotype with expansion of CD4(+) CD28null and CD8(+) CD28null cells. One year post-KT, the CD8(+) T cell count was almost doubled compared to nonviremic D+/R- and D+/R+ KT recipients. In addition, the RTL of the CD8(+) T cell was significantly lower and both the TREC content and CD31(+) naïve T cell numbers significantly decreased. Moreover, primary CMV infection was associated with a negative impact on glomerular filtration rate. In conclusion, primary CMV infection has a substantial impact on the number and phenotype of peripheral T cells and may negatively affect renal allograft function. PMID:26211927

  14. Expression of T-cell receptor beta-chain mRNA and protein in gamma/delta T-cells from euthymic and athymic rats: implications for T-cell lineage divergence.

    PubMed

    Bischof, A; Park, J H; Hünig, T

    2000-01-01

    The relationship between alpha/beta and gamma/delta T-cell lineages was studied in rats using RT-PCR analysis of TCRbeta transcripts in gamma/delta T-cell hybridomas and an intracellular staining technique to detect TCRbeta protein in primary gamma/delta T-cells. We report the presence of functional TCRbeta transcripts in 2/9 gamma/delta T-cell hybridomas. About 15% of peripheral gamma/delta T-cells and thymocytes also express TCRbeta protein, giving a minimum estimate for successful Tcrb rearrangement based on ex vivo single cell analysis. In athymic rats, gamma/delta T-cells expressing intracellular beta protein are present but at a lower frequency than in euthymic controls, suggesting that in the thymus, more gamma/delta T-cell precursors pass through a stage where functional beta rearrangement has occurred than in extrathymic sites. Analysis of TCR expression in purified transitory immature CD4-8+ (iCD8SP) thymocytes and their spontaneously developing CD4+8+ (DP) progeny showed that TCRy mRNA is expressed in iCD8SP cells but not in their immediate DP progeny that reinitiate RAG-I transcription and commence alpha/betaTCR expression. We conclude that rat gamma/delta T cells can separate from the alpha/beta lineage after TCRbeta expression, but not after entry into the DP compartment. PMID:11293809

  15. Itk: The Rheostat of the T Cell Response

    PubMed Central

    Grasis, Juris A.; Tsoukas, Constantine D.

    2011-01-01

    The nonreceptor tyrosine kinase Itk plays a key role in TCR-initiated signaling that directly and significantly affects the regulation of PLC?1 and the consequent mobilization of Ca2+. Itk also participates in the regulation of cytoskeletal reorganization as well as cellular adhesion, which is necessary for a productive T cell response. The functional cellular outcome of these molecular regulations by Itk renders it an important mediator of T cell development and differentiation. This paper encompasses the structure of Itk, the signaling parameters leading to Itk activation, and Itk effects on molecular pathways resulting in functional cellular outcomes. The incorporation of these factors persuades one to believe that Itk serves as a modulator, or rheostat, critically fine-tuning the T cell response. PMID:21747996

  16. Vitronectin is not essential for normal mammalian development and fertility.

    PubMed Central

    Zheng, X; Saunders, T L; Camper, S A; Samuelson, L C; Ginsburg, D

    1995-01-01

    Vitronectin (VN) is an abundant glycoprotein present in plasma and the extracellular matrix of most tissues. Though the precise function of VN in vivo is unknown, it has been implicated as a participant in diverse biological processes, including cell attachment and spreading, complement activation, and regulation of hemostasis. The major site of synthesis appears to be the liver, though VN is also found in the brain at an early stage of mouse organogenesis, suggesting that it may play an important role in mouse development. Genetic deficiency of VN has not been reported in humans or in other higher organisms. To examine the biologic function of VN within the context of the intact animal, we have established a murine model for VN deficiency through targeted disruption of the murine VN gene. Southern blot analysis of DNA obtained from homozygous null mice demonstrates deletion of all VN coding sequences, and immunological analysis confirms the complete absence of VN protein expression in plasma. However, heterozygous mice carrying one normal and one null VN allele and homozygous null mice completely deficient in VN demonstrate normal development, fertility, and survival. Sera obtained from VN-deficient mice are completely deficient in "serum spreading factor" and plasminogen activator inhibitor 1 binding activities. These observations demonstrate that VN is not essential for cell adhesion and migration during normal mouse development and suggest that its role in these processes may partially overlap with other adhesive matrix components. Images Fig. 1 Fig. 2 Fig. 3 PMID:8618914

  17. Homeostatic T Cell Proliferation after Islet Transplantation

    PubMed Central

    Monti, Paolo; Piemonti, Lorenzo

    2013-01-01

    Pancreatic islet transplantation in patients with type 1 diabetes mellitus is performed under immunosuppression to avoid alloreactive T cell responses and to control the reactivation of autoreactive memory T cells. However, lymphopenia associated with immunosuppression and T cell depletion can induce a paradoxical expansion of lymphocyte subsets under the influence of homeostatic proliferation. Homeostatic T cell proliferation is mainly driven by the IL-7/IL-7 receptor axis, a molecular pathway which is not affected by standard immune-suppressive drugs and, consequently, represents a novel potential target for immuno-modulatory strategies. In this review, we will discuss how homeostatic T cell proliferation can support autoimmunity recurrence after islet transplantation and how it can be targeted by new therapeutic approaches. PMID:23970924

  18. T cell immunity using transgenic B lymphocytes

    NASA Astrophysics Data System (ADS)

    Gerloni, Mara; Rizzi, Marta; Castiglioni, Paola; Zanetti, Maurizio

    2004-03-01

    Adaptive immunity exists in all vertebrates and plays a defense role against microbial pathogens and tumors. T cell responses begin when precursor T cells recognize antigen on specialized antigen-presenting cells and differentiate into effector cells. Currently, dendritic cells are considered the only cells capable of stimulating T lymphocytes. Here, we show that mature naïve B lymphocytes can be genetically programmed by using nonviral DNA and turned into powerful antigen-presenting cells with a dual capacity of synthesis and presentation of antigen to T cells in vivo. A single i.v. injection of transgenic lymphocytes activates T cell responses reproducibly and specifically even at very low cell doses (102). We also demonstrate that T cell priming can occur in the absence of dendritic cells and results in immunological memory with protective effector functions. These findings disclose aspects in the regulation of adaptive immunity and indicate possibilities for vaccination against viruses and cancer in humans.

  19. Placing Ion Channels into a Signaling Network of T Cells: From Maturing Thymocytes to Healthy T Lymphocytes or Leukemic T Lymphoblasts

    PubMed Central

    Delgado-Enciso, Iván; Best-Aguilera, Carlos; Rojas-Sotelo, Rocío Monserrat; Pottosin, Igor

    2015-01-01

    T leukemogenesis is a multistep process, where the genetic errors during T cell maturation cause the healthy progenitor to convert into the leukemic precursor that lost its ability to differentiate but possesses high potential for proliferation, self-renewal, and migration. A new misdirecting “leukemogenic” signaling network appears, composed by three types of participants which are encoded by (1) genes implicated in determined stages of T cell development but deregulated by translocations or mutations, (2) genes which normally do not participate in T cell development but are upregulated, and (3) nondifferentially expressed genes which become highly interconnected with genes expressed differentially. It appears that each of three groups may contain genes coding ion channels. In T cells, ion channels are implicated in regulation of cell cycle progression, differentiation, activation, migration, and cell death. In the present review we are going to reveal a relationship between different genetic defects, which drive the T cell neoplasias, with calcium signaling and ion channels. We suggest that changes in regulation of various ion channels in different types of the T leukemias may provide the intracellular ion microenvironment favorable to maintain self-renewal capacity, arrest differentiation, induce proliferation, and enhance motility. PMID:25866806

  20. NAD+ protects against EAE by regulating CD4+ T-cell differentiation

    PubMed Central

    Tullius, Stefan G.; Biefer, Hector Rodriguez Cetina; Li, Suyan; Trachtenberg, Alexander J.; Edtinger, Karoline; Quante, Markus; Krenzien, Felix; Uehara, Hirofumi; Yang, Xiaoyong; Kissick, Haydn T.; Kuo, Winston P.; Ghiran, Ionita; de la Fuente, Miguel A.; Arredouani, Mohamed S.; Camacho, Virginia; Tigges, John C.; Toxavidis, Vasilis; El Fatimy, Rachid; Smith, Brian D.; Vasudevan, Anju; ElKhal, Abdallah

    2014-01-01

    CD4+ T cells are involved in the development of autoimmunity, including multiple sclerosis (MS). Here we show that nicotinamide adenine dinucleotide (NAD+) blocks experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, by inducing immune homeostasis through CD4+IFN?+IL-10+ T cells and reverses disease progression by restoring tissue integrity via remyelination and neuroregeneration. We show that NAD+ regulates CD4+ T-cell differentiation through tryptophan hydroxylase-1 (Tph1), independently of well-established transcription factors. In the presence of NAD+, the frequency of T-bet?/? CD4+IFN?+ T cells was twofold higher than wild-type CD4+ T cells cultured in conventional T helper 1 polarizing conditions. Our findings unravel a new pathway orchestrating CD4+ T-cell differentiation and demonstrate that NAD+ may serve as a powerful therapeutic agent for the treatment of autoimmune and other diseases. PMID:25290058

  1. Regulation of proximal T cell receptor signaling and tolerance induction by deubiquitinase Usp9X

    PubMed Central

    Naik, Edwina; Webster, Joshua D.; DeVoss, Jason; Liu, Jinfeng; Suriben, Rowena

    2014-01-01

    The T cell hyperproliferation and autoimmune phenotypes that manifest in mice lacking E3 ubiquitin ligases such as Cbl, ITCH, or GRAIL highlight the importance of ubiquitination for the maintenance of peripheral T cell tolerance. Less is known, however, about the deubiquitinating enzymes that regulate T cell proliferation and effector function. Here, we define a cell intrinsic role for the deubiquitinase Usp9X during proximal TCR signaling. Usp9X-deficient T cells were hypoproliferative, yet mice with T cell–specific Usp9x deletion had elevated numbers of antigen-experienced T cells and expanded PD-1 and OX40-expressing populations consistent with immune hyperactivity. Aged Usp9x KO mice developed lupus-like autoimmunity and lymphoproliferative disease, indicating that ubiquitin ligases and deubiquitinases maintain the delicate balance between effective immunity and self-tolerance. PMID:25200027

  2. Inhibitory Receptors Beyond T Cell Exhaustion

    PubMed Central

    Fuertes Marraco, Silvia A.; Neubert, Natalie J.; Verdeil, Grégory; Speiser, Daniel E.

    2015-01-01

    Inhibitory receptors (iRs) are frequently associated with “T cell exhaustion”. However, the expression of iRs is also dependent on T cell differentiation and activation. Therapeutic blockade of various iRs, also referred to as “checkpoint blockade”, is showing ­unprecedented results in the treatment of cancer patients. Consequently, the clinical potential in this field is broad, calling for increased research efforts and rapid refinements in the understanding of iR function. In this review, we provide an overview on the significance of iR expression for the interpretation of T cell functionality. We summarize how iRs have been strongly associated with “T cell exhaustion” and illustrate the parallel evidence on the importance of T cell differentiation and activation for the expression of iRs. The differentiation subsets of CD8 T cells (naïve, effector, and memory cells) show broad and inherent differences in iR expression, while activation leads to strong upregulation of iRs. Therefore, changes in iR expression during an immune response are often concomitant with T cell differentiation and activation. Sustained expression of iRs in chronic infection and in the tumor microenvironment likely reflects a specialized T cell differentiation. In these situations of prolonged antigen exposure and chronic inflammation, T cells are “downtuned” in order to limit tissue damage. Furthermore, we review the novel “checkpoint blockade” treatments and the potential of iRs as biomarkers. Finally, we provide recommendations for the immune monitoring of patients to interpret iR expression data combined with parameters of activation and differentiation of T cells. PMID:26167163

  3. Effector V?9V?2 T cells dominate the human fetal ?? T-cell repertoire

    PubMed Central

    Dimova, Tanya; Brouwer, Margreet; Gosselin, Françoise; Tassignon, Joël; Leo, Oberdan; Donner, Catherine; Marchant, Arnaud; Vermijlen, David

    2015-01-01

    ?? T cells are unconventional T cells recognizing antigens via their ?? T-cell receptor (TCR) in a way that is fundamentally different from conventional ?? T cells. ?? T cells usually are divided into subsets according the type of V? and/or V? chain they express in their TCR. T cells expressing the TCR containing the ?-chain variable region 9 and the ?-chain variable region 2 (V?9V?2 T cells) are the predominant ?? T-cell subset in human adult peripheral blood. The current thought is that this predominance is the result of the postnatal expansion of cells expressing particular complementary-determining region 3 (CDR3) in response to encounters with microbes, especially those generating phosphoantigens derived from the 2-C-methyl-d-erythritol 4-phosphate pathway of isoprenoid synthesis. However, here we show that, rather than requiring postnatal microbial exposure, V?9V?2 T cells are the predominant blood subset in the second-trimester fetus, whereas V?1+ and V?3+ ?? T cells are present only at low frequencies at this gestational time. Fetal blood V?9V?2 T cells are phosphoantigen responsive and display very limited diversity in the CDR3 of the V?9 chain gene, where a germline-encoded sequence accounts for >50% of all sequences, in association with a prototypic CDR3?2. Furthermore, these fetal blood V?9V?2 T cells are functionally preprogrammed (e.g., IFN-? and granzymes-A/K), with properties of rapidly activatable innatelike T cells. Thus, enrichment for phosphoantigen-responsive effector T cells has occurred within the fetus before postnatal microbial exposure. These various characteristics have been linked in the mouse to the action of selecting elements and would establish a much stronger parallel between human and murine ?? T cells than is usually articulated. PMID:25617367

  4. Human ovarian tumor ascites fluids rapidly and reversibly inhibit T cell receptor-induced NF-?B and NFAT signaling in tumor-associated T cells

    PubMed Central

    Simpson-Abelson, Michelle R.; Loyall, Jenni L.; Lehman, Heather K.; Barnas, Jennifer L.; Minderman, Hans; O’Loughlin, Kieran L.; Wallace, Paul K.; George, Thaddeus C.; Peng, Peng; Kelleher, Raymond J.; Odunsi, Kunle; Bankert, Richard B.

    2013-01-01

    Human memory T cells present in ovarian tumor ascites fluids fail to respond normally to stimulation via the T cell receptor (TCR). This immunosuppression is manifested by decreases in NF-?B and NFAT activation, IFN-? production, and cell proliferation in response to TCR stimulation with immobilized antibodies to CD3 and CD28. The anergy of the tumor-associated T cells (TATs) is mediated by soluble factors present in ovarian tumor ascites fluids. The non-responsiveness of the T cells is quickly reversed when the cells are assayed in the absence of the ascites fluid, and is rapidly reestablished when a cell-free ascites fluid is added back to the T cells. Based upon the observed normal phosphorylation patterns of the TCR proximal signaling molecules, the inhibition of NF-?B, and NFAT activation in response to TCR stimulation, as well as the ability of the diacylglycerol analog PMA and the ionophore ionomycin to bypass the ascites fluid-induced TCR signaling arrest, the site of the arrest in the activation cascade appears to be at or just upstream of PLC-?. An identical TCR signaling arrest pattern was observed when T cells derived from normal donor peripheral blood were incubated with either malignant or nonmalignant (cirrhotic) ascites fluids. The immunosuppressive activity of ascites fluids reported here suggests that soluble factors acting directly or indirectly upon T cells present within tumors contribute to the anergy that has previously been observed in T cells derived from malignant and nonmalignant inflammatory microenvironments. The soluble immunosuppressive factors represent potential therapeutic targets for ovarian cancer. PMID:23882159

  5. Regulatory T cells and vasectomy.

    PubMed

    Rival, Claudia; Wheeler, Karen; Jeffrey, Sarah; Qiao, Hui; Luu, Brian; Tewalt, Eric F; Engelhard, Victor H; Tardif, Stephen; Hardy, Daniel; del Rio, Roxana; Teuscher, Cory; Tung, Kenneth

    2013-11-01

    CD4+ CD25+ regulatory T cells (Tregs) strongly influence the early and late autoimmune responses to meiotic germ cell antigens (MGCA) and the gonadal immunopathology in vasectomized mice. This is supported by the published and recently acquired information presented here. Within 24h of unilateral vasectomy (uni-vx) the ipsilateral epididymis undergoes epithelial cell apoptosis followed by necrosis, severe inflammation, and granuloma formation. Unexpectedly, vasectomy alone induced MGCA-specific tolerance. In contrast, uni-vx plus simultaneous Treg depletion resulted in MGCA-specific autoimmune response and bilateral autoimmune orchitis. Both tolerance and autoimmunity were strictly linked to the early epididymal injury. We now discovered that testicular autoimmunity in uni-vx mice did not occur when Treg depletion was delayed by one week. Remarkably, this delayed Treg depletion also prevented tolerance induction. Therefore, tolerance depends on a rapid de novo Treg response to MGCA exposed after vasectomy. Moreover, tolerance was blunted in mice genetically deficient in PD-1 ligand, suggesting the involvement of induced Treg. We conclude that pre-existing natural Treg prevents post-vasectomy autoimmunity, whereas vasectomy-induced Treg maintains post-vasectomy tolerance. We further discovered that vasectomized mice were still resistant to autoimmune orchitis induction for at least 12-16 months; thus, tolerance is long-lasting. Although significant sperm autoantibodies of low titers became detectable in uni-vx mice at 7 months, the antibody titers fluctuated over time, suggesting a dynamic "balance" between the autoimmune and tolerance states. Finally, we observed severe epididymal fibrosis and hypo-spermatogenesis at 12 months after uni-vx: findings of highly critical clinical significance. PMID:24080233

  6. X Chromosome Abnormalities and Cognitive Development: Implications for Understanding Normal Human Development.

    ERIC Educational Resources Information Center

    Walzer, Stanley

    1985-01-01

    Argues that knowledge from studies of individuals with sex chromosome abnormalities can further understanding of aspects of normal human development. Studies of XO girls, XXY boys, XXX girls, and males with a fragile X chromosome are summarized to demonstrate how results contribute to knowledge about normal cognitive development and about…

  7. Patient-derived glioblastoma stem cells are killed by CD133-specific CAR T cells but induce the T cell aging marker CD57

    PubMed Central

    Zhu, Xuekai; Prasad, Shruthi; Gaedicke, Simone; Hettich, Michael; Firat, Elke; Niedermann, Gabriele

    2015-01-01

    The AC133 epitope of CD133 is a cancer stem cell (CSC) marker for many tumor entities, including the highly malignant glioblastoma multiforme (GBM). We have developed an AC133-specific chimeric antigen receptor (CAR) and show that AC133-CAR T cells kill AC133+ GBM stem cells (GBM-SCs) both in vitro and in an orthotopic tumor model in vivo. Direct contact with patient-derived GBM-SCs caused rapid upregulation of CD57 on the CAR T cells, a molecule known to mark terminally or near-terminally differentiated T cells. However, other changes associated with terminal T cell differentiation could not be readily detected. CD57 is also expressed on tumor cells of neural crest origin and has been preferentially found on highly aggressive, undifferentiated, multipotent CSC-like cells. We found that CD57 was upregulated on activated T cells only upon contact with CD57+ patient-derived GBM-SCs, but not with conventional CD57-negative glioma lines. However, CD57 was not downregulated on the GBM-SCs upon their differentiation, indicating that this molecule is not a bona fide CSC marker for GBM. Differentiated GBM cells still induced CD57 on CAR T cells and other activated T cells. Therefore, CD57 can apparently be upregulated on activated human T cells by mere contact with CD57+ target cells. PMID:25426558

  8. Memory T cells maintain protracted protection against malaria.

    PubMed

    Krzych, Urszula; Zarling, Stasya; Pichugin, Alexander

    2014-10-01

    Immunologic memory is one of the cardinal features of antigen-specific immune responses, and the persistence of memory cells contributes to prophylactic immunizations against infectious agents. Adequately maintained memory T and B cell pools assure a fast, effective and specific response against re-infections. However, many aspects of immunologic memory are still poorly understood, particularly immunologic memory inducible by parasites, for example, Plasmodium spp., the causative agents of malaria. For example, memory responses to Plasmodium antigens amongst residents of malaria endemic areas appear to be either inadequately developed or maintained, because persons who survive episodes of childhood malaria remain vulnerable to intermittent malaria infections. By contrast, multiple exposures of humans and laboratory rodents to radiation-attenuated Plasmodium sporozoites (?-spz) induce sterile and long-lasting protection against experimental sporozoite challenge. Multifactorial immune mechanisms maintain this protracted and sterile protection. While the presence of memory CD4 T cell subsets has been associated with lasting protection in humans exposed to multiple bites from Anopheles mosquitoes infected with attenuated Plasmodium falciparum, memory CD8 T cells maintain protection induced with Plasmodium yoelii and Plasmodium berghei ?-spz in murine models. In this review, we discuss our observations that show memory CD8 T cells specific for antigens expressed by P. berghei liver stage parasites as an indispensable component for the maintenance of protracted protective immunity against experimental malaria infection; moreover, the provision of an Ag-depot assures a quick recall of memory T cells as IFN-?-producing effector CD8 T cells and IL-4- producing CD4 T cells that collaborate with B cells for an effective antibody response. PMID:24709142

  9. CXorf61 is a target for T cell based immunotherapy of triple-negative breast cancer.

    PubMed

    Paret, Claudia; Simon, Petra; Vormbrock, Kirsten; Bender, Christian; Kölsch, Anne; Breitkreuz, Andrea; Yildiz, Özlem; Omokoko, Tana; Hubich-Rau, Stefanie; Hartmann, Christoph; Häcker, Sabine; Wagner, Meike; Roldan, Diana Barea; Selmi, Abderaouf; Türeci, Özlem; Sahin, Ugur

    2015-09-22

    Triple-negative breast cancer (TNBC) is a high medical need disease with limited treatment options. CD8+ T cell-mediated immunotherapy may represent an attractive approach to address TNBC. The objectives of this study were to assess the expression of CXorf61 in TNBCs and healthy tissues and to evaluate its capability to induce T cell responses. We show by transcriptional profiling of a broad comprehensive set of normal human tissue that CXorf61 expression is strictly restricted to testis. 53% of TNBC patients express this antigen in at least 30% of their tumor cells. In CXorf61-negative breast cancer cell lines CXorf61 expression is activated by treatment with the hypomethylating agent 5-aza-2'-deoxycytidine. By vaccination of HLA-A*02-transgenic mice with CXorf61 encoding RNA we obtained high frequencies of CXorf61-specific T cells. Cloning and characterization of T cell receptors (TCRs) from responding T cells resulted in the identification of the two HLA-A*0201-restricted T cell epitopes CXorf6166-74 and CXorf6179-87. Furthermore, by in vitro priming of human CD8+ T cells derived from a healthy donor recognizing CXorf6166-74 we were able to induce a strong antigen-specific immune response and clone a human TCR recognizing this epitope. In summary, our data confirms this antigen as promising target for T cell based therapies. PMID:26327325

  10. A stochastic T cell response criterion

    PubMed Central

    Currie, James; Castro, Mario; Lythe, Grant; Palmer, Ed; Molina-París, Carmen

    2012-01-01

    The adaptive immune system relies on different cell types to provide fast and coordinated responses, characterized by recognition of pathogenic challenge, extensive cellular proliferation and differentiation, as well as death. T cells are a subset of the adaptive immune cellular pool that recognize immunogenic peptides expressed on the surface of antigen-presenting cells by means of specialized receptors on their membrane. T cell receptor binding to ligand determines T cell responses at different times and locations during the life of a T cell. Current experimental evidence provides support to the following: (i) sufficiently long receptor–ligand engagements are required to initiate the T cell signalling cascade that results in productive signal transduction and (ii) counting devices are at work in T cells to allow signal accumulation, decoding and translation into biological responses. In the light of these results, we explore, with mathematical models, the timescales associated with T cell responses. We consider two different criteria: a stochastic one (the mean time it takes to have had N receptor–ligand complexes bound for at least a dwell time, ?, each) and one based on equilibrium (the time to reach a threshold number N of receptor–ligand complexes). We have applied mathematical models to previous experiments in the context of thymic negative selection and to recent two-dimensional experiments. Our results indicate that the stochastic criterion provides support to the thymic affinity threshold hypothesis, whereas the equilibrium one does not, and agrees with the ligand hierarchy experimentally established for thymic negative selection. PMID:22745227

  11. T CELL REPLICATIVE SENESCENCE IN HUMAN AGING

    PubMed Central

    Chou, Jennifer P.; Effros, Rita B.

    2013-01-01

    The decline of the immune system appears to be an intractable consequence of aging, leading to increased susceptibility to infections, reduced effectiveness of vaccination and higher incidences of many diseases including osteoporosis and cancer in the elderly. These outcomes can be attributed, at least in part, to a phenomenon known as T cell replicative senescence, a terminal state characterized by dysregulated immune function, loss of the CD28 costimulatory molecule, shortened telomeres and elevated production of pro-inflammatory cytokines. Senescent CD8 T cells, which accumulate in the elderly, have been shown to frequently bear antigen specificity against cytomegalovirus (CMV), suggesting that this common and persistent infection may drive immune senescence and result in functional and phenotypic changes to the T cell repertoire. Senescent T cells have also been identified in patients with certain cancers, autoimmune diseases and chronic infections, such as HIV. This review discusses the in vivo and in vitro evidence for the contribution of CD8 T cell replicative senescence to a plethora of age-related pathologies and a few possible therapeutic avenues to delay or prevent this differentiative end-state in T cells. The age-associated remodeling of the immune system, through accumulation of senescent T cells has far-reaching consequences on the individual and society alike, for the current healthcare system needs to meet the urgent demands of the increasing proportions of the elderly in the US and abroad. PMID:23061726

  12. The Vitamin D Receptor and T Cell Function

    PubMed Central

    Kongsbak, Martin; Levring, Trine B.; Geisler, Carsten; von Essen, Marina Rode

    2013-01-01

    The vitamin D receptor (VDR) is a nuclear, ligand-dependent transcription factor that in complex with hormonally active vitamin D, 1,25(OH)2D3, regulates the expression of more than 900 genes involved in a wide array of physiological functions. The impact of 1,25(OH)2D3-VDR signaling on immune function has been the focus of many recent studies as a link between 1,25(OH)2D3 and susceptibility to various infections and to development of a variety of inflammatory diseases has been suggested. It is also becoming increasingly clear that microbes slow down immune reactivity by dysregulating the VDR ultimately to increase their chance of survival. Immune modulatory therapies that enhance VDR expression and activity are therefore considered in the clinic today to a greater extent. As T cells are of great importance for both protective immunity and development of inflammatory diseases a variety of studies have been engaged investigating the impact of VDR expression in T cells and found that VDR expression and activity plays an important role in both T cell development, differentiation and effector function. In this review we will analyze current knowledge of VDR regulation and function in T cells and discuss its importance for immune activity. PMID:23785369

  13. T-cell immunity in murine malaria: adoptive transfer of resistance to Plasmodium chabaudi adami in nude mice with splenic T cells.

    PubMed Central

    Cavacini, L A; Long, C A; Weidanz, W P

    1986-01-01

    Acute infections caused by the murine malarial parasite Plasmodium chabaudi adami are resolved by antibody-independent mechanisms of immunity. The fact that athymic nude mice developed high-grade unrelenting malaria and died when infected with this parasite suggested a significant role for T lymphocytes. Using adoptive transfer techniques, we demonstrated that spleen cells from either nonimmune or immune donor BALB/c mice eventually suppressed P. chabaudi adami infections in histocompatible recipient nude mice in a dose-dependent manner. Infections in recipients of "immune" spleen cells were less severe, demonstrating a depressed peak parasitemia and a shortened duration of patent infection, than was observed in recipients of normal spleen cells. Also, when sufficient numbers of immune spleen cells were transferred, the second wave of parasitemia (characteristic of this infection in nonimmune mice) failed to occur. T lymphocytes mediated protection in recipient mice, since T-cell-enriched, but not B-cell-enriched, spleen cell fractions suppressed P. chabaudi adami infections in nude mice. Protection was best achieved with T cells that bore the L3T4 phenotype. Patent parasitemias developed in all recipient mice, suggesting that the grafted cells did not limit parasite growth directly but achieved this end by activating other as yet unidentified inhibiting cell systems. PMID:3086229

  14. Human cytotoxic T-cell memory: long-lived responses to vaccinia virus.

    PubMed Central

    Demkowicz, W E; Littaua, R A; Wang, J; Ennis, F A

    1996-01-01

    Peripheral T lymphocytes can be classified into two groups: naive and memory T cells. The focus of this study was to examine the duration of T-cell memory in humans. Vaccinia virus replicates in the cytoplasm of infected cells and is not thought to persist or become latent after the acute phase of infection. We identified long-lived vaccinia virus-specific memory cytotoxic T cells in adults who had been immunized against smallpox as children. Initially, we detected vaccinia virus-specific T cells in peripheral blood mononuclear cells while screening for human immunodeficiency virus type 1 (HIV-1)-specific T-cell responses in HIV-1-seropositive subjects. These individuals had not had contact with vaccinia virus since their primary immunization in early childhood. Several vaccinia virus-specific CD4+ T-cell clones were derived from these donors and characterized. Healthy, HIV-1-seronegative donors who had been immunized against smallpox many (35 to 50) years earlier were also screened for vaccinia virus-specific T-cell immunity. We found significant CD8+ and CD4+ cytotoxic T-cell responses to vaccinia virus after in vitro stimulation, indicating that these memory cells are maintained in vivo for many years. The peripheral blood mononuclear cells of young adults with no history of immunization against smallpox did not develop vaccinia virus-specific T-cell responses after in vitro stimulation. Precursor frequency analysis of the vaccinia virus-specific memory CD4+ T cells from a donor immunized with vaccinia virus 35 years earlier revealed a frequency of 1 in 65,920 CD4+ T cells. We concluded that specific vaccinia virus T-cell immunity can persist for up to 50 years after immunization against smallpox in childhood in the presumed absence of exposure to vaccinia virus. PMID:8642697

  15. Targeting IRAK1 in T-cell acute lymphoblastic leukemia.

    PubMed

    Dussiau, Charles; Trinquand, Amélie; Lhermitte, Ludovic; Latiri, Mehdi; Simonin, Mathieu; Cieslak, Agata; Bedjaoui, Nawel; Villarèse, Patrick; Verhoeyen, Els; Dombret, Hervé; Ifrah, Norbert; Macintyre, Elizabeth; Asnafi, Vahid

    2015-08-01

    T-cell acute lymphoblastic leukemia (T-ALL) represents expansion of cells arrested at specific stages of thymic development with the underlying genetic abnormality often determining the stage of maturation arrest. Although their outcome has been improved with current therapy, survival rates remain only around 50% at 5 years and patients may therefore benefit from specific targeted therapy. Interleukin receptor associated kinase 1 (IRAK1) is a ubiquitously expressed serine/threonine kinase that mediates signaling downstream to Toll-like (TLR) and Interleukin-1 Receptors (IL1R). Our data demonstrated that IRAK1 is overexpressed in all subtypes of T-ALL, compared to normal human thymic subpopulations, and is functional in T-ALL cell lines. Genetic knock-down of IRAK1 led to apoptosis, cell cycle disruption, diminished proliferation and reversal of corticosteroid resistance in T-ALL cell lines. However, pharmacological inhibition of IRAK1 using a small molecule inhibitor (IRAK1/4-Inh) only partially reproduced the results of the genetic knock-down. Altogether, our data suggest that IRAK1 is a candidate therapeutic target in T-ALL and highlight the requirement of next generation IRAK1 inhibitors. PMID:26068967

  16. Targeting IRAK1 in T-Cell acute lymphoblastic leukemia

    PubMed Central

    Lhermitte, Ludovic; Latiri, Mehdi; Simonin, Mathieu; Cieslak, Agata; Bedjaoui, Nawel; Villarèse, Patrick; Verhoeyen, Els; Dombret, Hervé; Ifrah, Norbert; Macintyre, Elizabeth; Asnafi, Vahid

    2015-01-01

    T-cell acute lymphoblastic leukemia (T-ALL) represents expansion of cells arrested at specific stages of thymic development with the underlying genetic abnormality often determining the stage of maturation arrest. Although their outcome has been improved with current therapy, survival rates remain only around 50% at 5 years and patients may therefore benefit from specific targeted therapy. Interleukin receptor associated kinase 1 (IRAK1) is a ubiquitously expressed serine/threonine kinase that mediates signaling downstream to Toll-like (TLR) and Interleukin-1 Receptors (IL1R). Our data demonstrated that IRAK1 is overexpressed in all subtypes of T-ALL, compared to normal human thymic subpopulations, and is functional in T-ALL cell lines. Genetic knock-down of IRAK1 led to apoptosis, cell cycle disruption, diminished proliferation and reversal of corticosteroid resistance in T-ALL cell lines. However, pharmacological inhibition of IRAK1 using a small molecule inhibitor (IRAK1/4-Inh) only partially reproduced the results of the genetic knock-down. Altogether, our data suggest that IRAK1 is a candidate therapeutic target in T-ALL and highlight the requirement of next generation IRAK1 inhibitors. PMID:26068967

  17. T-cell-independent elimination of Borrelia turicatae.

    PubMed Central

    Newman, K; Johnson, R C

    1984-01-01

    Mice deficient or deprived of thymus-derived lymphocytes eliminated blood-borne Borrelia turicatae with efficiency comparable to that observed in normal littermates. When challenged with 10(5) borreliae, nude mice had mean (+/- standard deviation) primary spirochetemias lasting 3.1 +/- 0.2 days and mean (+/- standard deviation) peak bacterial counts of 3.0 X 10(7) +/- 0.5 X 10(7) cells per ml of blood; in comparison, heterozygous littermates and normal mice had respective primary spirochetemias lasting 3.4 +/- 0.6 and 3.2 +/- 0.2 days and respective peak counts of 8.0 X 10(7) +/- 1.5 X 10(7) and 5.5 X 10(7) +/- 0.9 X 10(7) bacterial cells per ml of blood. No increased responsiveness to concanavalin A was observed in infected nude mice, indicating the sustained lack of maturate T cells in these animals. Thymectomized and steroid-treated mice were also found to eliminate circulating borreliae with efficiency comparable to that observed in control animals. Irradiation of mice abrogated responsiveness to borreliae, but reconstitution with T-cell-depleted splenocytes restored antibody production. It is proposed that elimination of B. turicatae is mediated by a T-cell-independent immune response mechanism. PMID:6332075

  18. PD-1 and Tim-3 Pathways Regulate CD8+ T Cells Function in Atherosclerosis

    PubMed Central

    Qiu, Ming-Ke; Wang, Song-Cun; Dai, Yu-Xin; Wang, Shu-Qing; Ou, Jing-Min; Quan, Zhi-Wei

    2015-01-01

    T cell-mediated immunity plays a significant role in the development of atherosclerosis (AS). There is increasing evidence that CD8+ T cells are also involved in AS but their exact roles remain unclear. The inhibitory receptors programmed cell death-1 (PD-1) and T cell immunoglobulin and mucin domain 3 (Tim-3) are well known inhibitory molecules that play a crucial role in regulating CD8+ T cell activation or tolerance. Here, we demonstrate that the co-expression of PD-1 and Tim-3 on CD8+ T cells is up-regulated in AS patients. PD-1+ Tim-3+ CD8+ T cells are enriched for within the central T (TCM) cell subset, with high proliferative activity and CD127 expression. Co-expression of PD-1 and Tim-3 on CD8+ T cells is associated with increased anti-atherogenic cytokine production as well as decreased pro-atherogenic cytokine production. Blockade of PD-1 and Tim-3 results in a decrease of anti-atherogenic cytokine production by PD-1+ Tim-3+ CD8+ T cells and in an augmentation of TNF-? and IFN-? production. These findings highlight the important role of the PD-1 and Tim-3 pathways in regulating CD8+ T cells function in human AS. PMID:26035207

  19. Regulation of T-cell activation and migration by the kinase TBK1 during neuroinflammation

    PubMed Central

    Yu, Jiayi; Zhou, Xiaofei; Chang, Mikyoung; Nakaya, Mako; Chang, Jae-Hoon; Xiao, Yichuan; William Lindsey, J.; Dorta-Estremera, Stephanie; Cao, Wei; Zal, Anna; Zal, Tomasz; Sun, Shao-Cong

    2015-01-01

    Development of an immune or autoimmune response involves T-cell activation in lymphoid organs and subsequent migration to peripheral tissues. Here we show that T-cell-specific ablation of the kinase TBK1 promotes T-cell activation but causes retention of effector T cells in the draining lymph node in a neuroinflammatory autoimmunity model, experimental autoimmune encephalomyelitis (EAE). At older ages, the T-cell-conditional TBK1-knockout mice also spontaneously accumulate T cells with activated phenotype. TBK1 controls the activation of AKT and its downstream kinase mTORC1 by a mechanism involving TBK1-stimulated AKT ubiquitination and degradation. The deregulated AKT-mTORC1 signalling in turn contributes to enhanced T-cell activation and impaired effector T-cell egress from draining lymph nodes. Treatment of mice with a small-molecule inhibitor of TBK1 inhibits EAE induction. These results suggest a role for TBK1 in regulating T-cell migration and establish TBK1 as a regulator of the AKT-mTORC1 signalling axis. PMID:25606824

  20. Bioengineering T cells to target carbohydrate to treat opportunistic fungal infection

    PubMed Central

    Kumaresan, Pappanaicken R.; Manuri, Pallavi R.; Albert, Nathaniel D.; Maiti, Sourindra; Singh, Harjeet; Mi, Tiejuan; Roszik, Jason; Rabinovich, Brian; Olivares, Simon; Krishnamurthy, Janani; Zhang, Ling; Najjar, Amer M.; Huls, M. Helen; Lee, Dean A.; Champlin, Richard E.; Kontoyiannis, Dimitrios P.; Cooper, Laurence J. N.

    2014-01-01

    Clinical-grade T cells are genetically modified ex vivo to express chimeric antigen receptors (CARs) to redirect their specificity to target tumor-associated antigens in vivo. We now have developed this molecular strategy to render cytotoxic T cells specific for fungi. We adapted the pattern-recognition receptor Dectin-1 to activate T cells via chimeric CD28 and CD3-? (designated “D-CAR”) upon binding with carbohydrate in the cell wall of Aspergillus germlings. T cells genetically modified with the Sleeping Beauty system to express D-CAR stably were propagated selectively on artificial activating and propagating cells using an approach similar to that approved by the Food and Drug Administration for manufacturing CD19-specific CAR+ T cells for clinical trials. The D-CAR+ T cells exhibited specificity for ?-glucan which led to damage and inhibition of hyphal growth of Aspergillus in vitro and in vivo. Treatment of D-CAR+ T cells with steroids did not compromise antifungal activity significantly. These data support the targeting of carbohydrate antigens by CAR+ T cells and provide a clinically appealing strategy to enhance immunity for opportunistic fungal infections using T-cell gene therapy. PMID:25002471

  1. Allogeneic T cell responses are regulated by a specific miRNA-mRNA network

    PubMed Central

    Sun, Yaping; Tawara, Isao; Zhao, Meng; Qin, Zhaohui S.; Toubai, Tomomi; Mathewson, Nathan; Tamaki, Hiroya; Nieves, Evelyn; Chinnaiyan, Arul M.; Reddy, Pavan

    2013-01-01

    Donor T cells that respond to host alloantigens following allogeneic bone marrow transplantation (BMT) induce graft-versus-host (GVH) responses, but their molecular landscape is not well understood. MicroRNAs (miRNAs) regulate gene (mRNA) expression and fine-tune the molecular responses of T cells. We stimulated naive T cells with either allogeneic or nonspecific stimuli and used argonaute cross-linked immunoprecipitation (CLIP) with subsequent ChIP microarray analyses to profile miR responses and their direct mRNA targets. We identified a unique expression pattern of miRs and mRNAs following the allostimulation of T cells and a high correlation between the expression of the identified miRs and a reduction of their mRNA targets. miRs and mRNAs that were predicted to be differentially regulated in allogeneic T cells compared with nonspecifically stimulated T cells were validated in vitro. These analyses identified wings apart-like homolog (Wapal) and synaptojanin 1 (Synj1) as potential regulators of allogeneic T cell responses. The expression of these molecular targets in vivo was confirmed in MHC-mismatched experimental BMT. Targeted silencing of either Wapal or Synj1 prevented the development of GVH response, confirming a role for these regulators in allogeneic T cell responses. Thus, this genome-wide analysis of miRNA-mRNA interactions identifies previously unrecognized molecular regulators of T cell responses. PMID:24216511

  2. CD43 is a murine T cell costimulatory receptor that functions independently of CD28

    PubMed Central

    1995-01-01

    Costimulation mediated by the CD28 receptor has been shown to play an important role in the development of a vigorous T cell immune response. Nevertheless, CD28-deficient mice can mount effective T cell-dependent immune responses. These data suggest that other costimulatory molecules may play a role in T cell activation. In a search for other costimulatory receptors on T cells, we have characterized a monoclonal antibody (mAb) that can costimulate T cells in the absence of accessory cells. Similar to CD28 antibodies, this mAb, R2/60, was found to synergize with T cell receptor engagement in inducing proliferation. Independent ligation of CD3 and the ligand recognized by R2/60 results in T cell proliferation, suggesting that the two molecules do not have to colocalize to activate the R2/60 costimulatory pathway. R2/60 does not react with CD28, and furthermore, R2/60 costimulates in a CD28- independent fashion since the mAb costimulates T cells from the CD28- deficient mice as well as wild-type mice. Expression cloning of the R2/60 antigen identified the ligand as murine CD43. Together, these data demonstrate that CD43 can serve as a receptor on T cells that can provide CD28-independent costimulation. PMID:7790813

  3. IL-15-dependent CD8+ CD122+ T cells ameliorate experimental autoimmune encephalomyelitis by modulating IL-17 production by CD4+ T cells.

    PubMed

    Yu, Ping; Bamford, Richard N; Waldmann, Thomas A

    2014-11-01

    Interleukin-15 (IL-15) is an inflammatory cytokine whose role in autoimmune diseases has not been fully elucidated. Th17 cells have been shown to play critical roles in experimental autoimmune encephalomyelitis (EAE) models. In this study, we demonstrate that blockade of IL-15 signaling by TM?-1 mAb treatment aggravated EAE severity. The key mechanism was not NK-cell depletion but depletion of CD8+ CD122+ T cells. Adoptive transfer of exogenous CD8+ CD122+ T cells to TM?-1-treated mice rescued animals from severe disease. Moreover, transfer of preactivated CD8+ CD122+ T cells prevented EAE development and significantly reduced IL-17 secretion. Naïve effector CD4+ CD25- T cells cultured with either CD8+ CD122+ T cells from wild-type mice or IL-15 transgenic mice displayed lower frequencies of IL-17A production with lower amounts of IL-17 in the supernatants when compared with production by effector CD4+ CD25- T cells cultured alone. Addition of a neutralizing antibody to IL-10 led to recovery of IL-17A production in Th17 cultures. Furthermore, coculture of CD8+ CD122+ T cells with effector CD4+ T cells inhibited their proliferation significantly, suggesting a regulatory function for IL-15 dependent CD8+ CD122+ T cells. Taken together, these observations suggest that IL-15, acting through CD8+ CD122+ T cells, has a negative regulatory role in reducing IL-17 production and Th17-mediated EAE inflammation. PMID:25142300

  4. Allosuppressor- and allohelper-T cells in acute and chronic graft-vs. -host (GVH) disease. III. Different Lyt subsets of donor T cells induce different pathological syndromes

    SciTech Connect

    Rolink, A.G.; Gleichmann, E.

    1983-08-01

    Previous work from this laboratory has led to the hypothesis that the stimulatory pathological symptoms of chronic graft-vs.-host disease (GVHD) are caused by alloreactive donor T helper (TH) cells, whereas the suppressive pathological symptoms of acute GVHD are caused by alloreactive T suppressor (TS) cells of the donor. We analyzed the Lyt phenotypes of B10 donor T cells required for the induction of either acute or chronic GVHD in H-2-different (B10 X DBA/2)F1 recipients. When nonirradiated F1 mice were used as the recipients, we found unseparated B10 T cells induced only a moderate formation of systemic lupus erythematosus (SLE)-like autoantibodies, but a high percentage of lethal GVHD (LGVHD). In contrast, Lyt-1+2- donor T cells were unable to induce LGVHD in these recipients but were capable of inducing a vigorous formation of SLE-like autoantibodies and severe immune-complex glomerulonephritis. Lyt-1-2+ T cells were incapable of inducing either acute or chronic GVHD. The sensitivity and accuracy of the GVH system were increased by using irradiated F1 mice as recipients and then comparing donor-cell inocula that contained similar numbers of T lymphocytes. Donor-cell inocula were used that had been tested for their allohelper and allosuppressor effects on F1 B cells in vitro. In the irradiated F1 recipients unseparated donor T cells were superior to T cell subsets in inducing LGVHD. In contrast Lyt-1+2- T cells, but neither unseparated T cells nor Lyt-1-2+ T cells, were capable of inducing a vigorous formation of SLE-like auto-antibodies. We conclude that the stimulatory pathological symptoms of chronic GVHD are caused by Lyt-1+2- allohelper T cells. In contrast, the development of the suppressive pathological symptoms of acute GVHD appears to involve alloreactive Lyt-1+2+ T suppressor cells.

  5. Major Role of ?? T Cells in the Generation of IL-17+ Uveitogenic T Cells1

    PubMed Central

    Cui, Yan; Shao, Hui; Lan, Chen; Nian, Hong; O'Brien, Rebecca L.; Born, Willi K.; Kaplan, Henry J.; Sun, Deming

    2014-01-01

    We show that in vitro activation of interphotoreceptor retinoid-binding protein (IRBP)-specific T cells from C57BL/6 mice immunized with an uveitogenic IRBP peptide (IRBP1–20) under TH17-polarizing conditions is associated with increased expansion of T cells expressing the ?? TCR. We also show that highly purified ?? or ?? T cells from C57BL/6 mice immunized with IRBP1–20 produced only small amounts of IL-17 after exposure to the immunizing Ag in vitro, whereas a mixture of the same T cells produced greatly increased amounts of IL-17. IRBP-induced T cells from IRBP-immunized TCR-??/?mice on the C57BL/6 genetic background produced significantly lower amounts of IL-17 than did wild-type C57BL/6 mice and had significantly decreased experimental autoimmune uveitis-inducing ability. However, reconstitution of the TCR-??/?mice before immunization with a small number of ?? T cells from IRBP-immunized C57BL/6 mice restored the disease-inducing capability of their IRBP-specific T cells and greatly enhanced the generation of IL-17+ T cells in the recipient mice. Our study suggests that ?? T cells are important in the generation and activation of IL-17-producing autoreactive T cells and play a major role in the pathogenesis of experimental autoimmune uveitis. PMID:19542467

  6. Synthetic biology approaches to engineer T cells Chia-Yung Wu1

    E-print Network

    Lim, Wendell

    Synthetic biology approaches to engineer T cells Chia-Yung Wu1 , Levi J Rupp1 , Kole T Roybal1 cellular behavior is growing rapidly with the development of synthetic biology. Here we describe how synthetic biology approaches are being used to rationally alter the behavior of T cells to optimize them

  7. A decrease of circulating CD4? T cells in Attwater's prairie chickens infected with reticuloendotheliosis virus 

    E-print Network

    Ferro, Pamela Joyce Bloomer

    2001-01-01

    of this project was to develop a method to monitor CD4? and CD8? T cells in prairie chickens and to determine if there was an alteration in the number of circulating T cells associated with REV infection in prairie chickens. A panel of anti-chicken monoclonal...

  8. Recurrent T cell receptor rearrangements in the cytotoxic T lymphocyte response in vivo against the p815 murine tumor

    PubMed Central

    1996-01-01

    P815 is a murine mastocytoma of DBA/2 origin which, although immunogenic, rapidly develops as a tumor in immunocompetent syngeneic hosts. In this report, we have studied, by a molecular approach, the in vivo alpha/beta T cell response to P815. Both situations of tumor growth after engraftment of naive animals or tumor rejection by preimmunized animals have been analyzed. The spectrum of T cell receptor beta chain rearrangements in the tumor-infiltrating lymphocytes was found to be highly variable among individual tumor- bearing mice. However, two rearrangements, one using V(beta)1 and J(beta)1.2 segments and one using the V(beta)1 and J(beta)2.5 segments, with conserved junctional regions, reproducibly emerge in most individuals. These two rearrangements thus correspond to "public" (recurrent) T cell clones, as opposed to "private" ones, which emerge in a seemingly stochastic fashion in immunized animals. Importantly, these public cells are observed in situations of either growth or rejection of the tumor. Quantification provides a clear increase in public T cells in secondary responses, but no obvious correlation provides between their level and primary tumor rejection. The V(beta)1- J(beta)1.2 rearrangement is borne by CTL directed against an antigen derived from P1A, a nonmutated mouse self protein which is expressed in P815 but not in normal mouse tissues except testis. A recurrent, public T cell response can thus be observed to an antigen derived from a self protein expressed by a tumor. PMID:8627157

  9. Cord blood T cells mediate enhanced antitumor effects compared with adult peripheral blood T cells.

    PubMed

    Hiwarkar, Prashant; Qasim, Waseem; Ricciardelli, Ida; Gilmour, Kimberly; Quezada, Sergio; Saudemont, Aurore; Amrolia, Persis; Veys, Paul

    2015-12-24

    Unrelated cord blood transplantation (CBT) without in vivo T-cell depletion is increasingly used to treat high-risk hematologic malignancies. Following T-replete CBT, naïve CB T cells undergo rapid peripheral expansion with memory-effector differentiation. Emerging data suggest that unrelated CBT, particularly in the context of HLA mismatch and a T-replete graft, may reduce leukemic relapse. To study the role of CB T cells in mediating graft-versus-tumor responses and dissect the underlying immune mechanisms for this, we compared the ability of HLA-mismatched CB and adult peripheral blood (PB) T cells to eliminate Epstein-Barr virus (EBV)-driven human B-cell lymphoma in a xenogeneic NOD/SCID/IL2rg(null) mouse model. CB T cells mediated enhanced tumor rejection compared with equal numbers of PB T cells, leading to improved survival in the CB group (P < .0003). Comparison of CB T cells that were autologous vs allogeneic to the lymphoma demonstrated that this antitumor effect was mediated by alloreactive rather than EBV-specific T cells. Analysis of tumor-infiltrating lymphocytes demonstrated that CB T cells mediated this enhanced antitumor effect by rapid infiltration of the tumor with CCR7(+)CD8(+) T cells and prompt induction of cytotoxic CD8(+) and CD4(+) T-helper (Th1) T cells in the tumor microenvironment. In contrast, in the PB group, this antilymphoma effect is impaired because of delayed tumoral infiltration of PB T cells and a relative bias toward suppressive Th2 and T-regulatory cells. Our data suggest that, despite being naturally programmed toward tolerance, reconstituting T cells after unrelated T-replete CBT may provide superior Tc1-Th1 antitumor effects against high-risk hematologic malignancies. PMID:26450984

  10. The normal development of Platynereis dumerilii (Nereididae, Annelida)

    PubMed Central

    2010-01-01

    Background The polychaete annelid Platynereis dumerilii is an emerging model organism for the study of molecular developmental processes, evolution, neurobiology and marine biology. Annelids belong to the Lophotrochozoa, the so far understudied third major branch of bilaterian animals besides deuterostomes and ecdysozoans. P. dumerilii has proven highly relevant to explore ancient bilaterian conditions via comparison to the deuterostomes, because it has accumulated less evolutionary change than conventional ecdysozoan models. Previous staging was mainly referring to hours post fertilization but did not allow matching stages between studies performed at (even slightly) different temperatures. To overcome this, and to provide a first comprehensive description of P. dumerilii normal development, a temperature-independent staging system is needed. Results Platynereis dumerilii normal development is subdivided into 16 stages, starting with the zygote and ending with the death of the mature worms after delivering their gametes. The stages described can be easily identified by conventional light microscopy or even by dissecting scope. Developmental landmarks such as the beginning of phototaxis, the visibility of the stomodeal opening and of the chaetae, the first occurrence of the ciliary bands, the formation of the parapodia, the extension of antennae and cirri, the onset of feeding and other characteristics are used to define different developmental stages. The morphology of all larval stages as well as of juveniles and adults is documented by light microscopy. We also provide an overview of important steps in the development of the nervous system and of the musculature, using fluorescent labeling techniques and confocal laser-scanning microscopy. Timing of each developmental stage refers to hours post fertilization at 18 ± 0.1°C. For comparison, we determined the pace of development of larvae raised at 14°C, 16°C, 20°C, 25°C, 28°C and 30°C. A staging ontology representing the comprehensive list of developmental stages of P. dumerilii is available online. Conclusions Our atlas of Platynereis dumerilii normal development represents an important resource for the growing Platynereis community and can also be applied to other nereidid annelids. PMID:21192805

  11. Development of ADA against recombinant human interferon beta in immune tolerant mice requires rapid recruitment of CD4? T cells, induces formation of germinal centers but lacks susceptibility for (most) adjuvants.

    PubMed

    Kijanka, Grzegorz; Sauerborn, Melody; Boon, Louis; Schellekens, Huub; Brinks, Vera

    2015-02-01

    Immunological processes leading to formation of antidrug antibodies (Abs) against recombinant human proteins remain poorly understood. Animal and clinical studies revealed that immunogenicity shares both T-cell-dependent (requirement of CD4(+) T cells, isotype switching) and T-cell-independent (involvement of Marginal Zone B cells, apparent lack of memory) characteristics. We used immune tolerant mice to study the mechanism underlying immunogenicity in more detail. We found that CD4(+) T cells were crucial at early stages of Ab responses against rhIFN?. In addition, we found a similar number of germinal centers (GCs) in spleen after rhIFN? treatment as after treatment with a foreign protein. However, neither Ab titers nor the number of GCs was increased by adsorption of rhIFN? on aluminum hydroxide. Therefore, we tested the effect of several immune adjuvants in a follow-up study. We found that only conjugation of rhIFN? to a carrier protein (cholera toxin subunit B) was effective in boosting Ab titers. However, these conjugates failed to trigger rhIFN? specific memory formation. Our findings show that early events of the immunogenicity reaction to self-proteins are CD4(+) T-cell dependent. Nevertheless, despite those similarities, immunogenicity of human proteins is clearly not a classical CD4(+) T-cell-dependent response. PMID:25219665

  12. The transcriptional landscape of ?? T cell differentiation

    E-print Network

    Regev, Aviv

    The differentiation of ??T cells from thymic precursors is a complex process essential for adaptive immunity. Here we exploited the breadth of expression data sets from the Immunological Genome Project to analyze how the ...

  13. CCR7 signaling inhibits T cell proliferation.

    PubMed

    Ziegler, Ekkehard; Oberbarnscheidt, Martin; Bulfone-Paus, Silvia; Förster, Reinhold; Kunzendorf, Ulrich; Krautwald, Stefan

    2007-11-15

    CCR7 and its ligands, CCL19 and CCL21, are responsible for directing the migration of T cells and dendritic cells into lymph nodes, where these cells play an important role in the initiation of the immune response. Recently, we have shown that systemic application of CCL19-IgG is able to inhibit the colocalization of T cells and dendritic cells within secondary lymphoid organs, resulting in pronounced immunosuppression with reduced allograft rejection after organ transplantation. In this study, we demonstrate that the application of sustained high concentrations of either soluble or immobilized CCL19 and CCL21 elicits an inhibitory program in T cells. We show that these ligands specifically interfere with cell proliferation and IL-2 secretion of CCR7(+) cells. This could be demonstrated for human and murine T cells and was valid for both CD4(+) and CD8(+) T cells. In contrast, CCL19 had no inhibitory effect on T cells from CCR7 knockout mice, but CCR7(-/-) T cells showed a proliferative response upon TCR-stimulation similar to that of CCL19-treated wild-type cells. Furthermore, the inhibition of proliferation is associated with delayed degradation of the cyclin-dependent kinase (CDK) inhibitor p27(Kip1) and the down-regulation of CDK1. This shows that CCR7 signaling is linked to cell cycle control and that sustained engagement of CCR7, either by high concentrations of soluble ligands or by high density of immobilized ligands, is capable of inducing cell cycle arrest in TCR-stimulated cells. Thus, CCR7, a chemokine receptor that has been demonstrated to play an essential role during activation of the immune response, is also competent to directly inhibit T cell proliferation. PMID:17982037

  14. Natural variants of cytotoxic epitopes are T-cell receptor antagonists for antiviral cytotoxic T cells

    NASA Astrophysics Data System (ADS)

    Bertoletti, Antonio; Sette, Alessandro; Chisari, Francis V.; Penna, Amalia; Levrero, Massimo; Carli, Marco De; Fiaccadori, Franco; Ferrari, Carlo

    1994-06-01

    IT has been suggested that mutations within immunodominant cytotoxic T-lymphocyte (CTL) epitopes may be exploited by viruses to evade protective immune responses critical for clearance1-4. Viral escape could originate from passive mechanisms, such as mutations within crucial CTL epitopes, either affecting major histocompatibility complex binding or T-cell antigen receptor (TCR) recognition. Additionally, it has recently been shown that substitutions of TCR contact sites can yield analogue peptides that can still interact with the T-cell receptor but be unable to deliver a full stimulatory signal, thus inducing anergy5 or acting as an antagonist for the TCR6-8. We report here that hepatitis B virus isolates derived from two chronically infected patients display variant epitopes that act as natural TCR antagonists with the capacity to inhibit the CTL response to the wild-type epitope. During natural infection, TCR antagonist mutations of CTL epitopes could contribute to the development of viral persistence, especially if the antiviral CTL response is monospecific or the epitope is strongly immunodominant.

  15. Development of Communicative Gestures in Normally Developing Children between 8 and 18 Months: An Exploratory Study

    ERIC Educational Resources Information Center

    Veena, Kadiyali D; Bellur, Rajashekhar

    2015-01-01

    Children who have not developed speech tend to use gestures to communicate. Since gestures are not encouraged and suppressed in the Indian traditional context while speaking, this study focused on profiling the developing gestures in children to explore whether they use the gestures before development of speech. Eight normally developing

  16. Design and Evaluation of Optimized Artificial HIV-1 Poly-T Cell-Epitope Immunogens

    PubMed Central

    Reguzova, Alena; Antonets, Denis; Karpenko, Larisa; Ilyichev, Alexander; Maksyutov, Rinat; Bazhan, Sergei

    2015-01-01

    A successful HIV vaccine in addition to induction of antibody responses should elicit effective T cell responses. Here we described possible strategies for rational design of T-cell vaccine capable to induce high levels of both CD4+ and CD8+ T- cell responses. We developed artificial HIV-1 polyepitope T-cell immunogens based on the conserved natural CD8+ and CD4+ T cell epitopes from different HIV-1 strains and restricted by the most frequent major human leukocyte antigen (HLA) alleles. Designed immunogens contain optimized core polyepitope sequence and additional “signal” sequences which increase epitope processing and presentation to CD8+ and CD4+ T-lymphocytes: N-terminal ubiquitin, N-terminal signal peptide and C-terminal tyrosine motif of LAMP-1 protein. As a result we engineered three T cell immunogens – TCI-N, TCI-N2, and TCI-N3, with different combinations of signal sequences. All designed immunogens were able to elicit HIV-specific CD4+ and CD8+ T cell responses following immunization. Attachment of either ubiquitin or