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Sample records for normal t-cell development

  1. Cell adhesion molecules involved in intrathymic T cell development.

    PubMed

    Patel, D D; Haynes, B F

    1993-08-01

    During stem cell migration to the thymus, intrathymic maturation of T cells, and emigration of mature T cells out of the thymus, intercellular interactions of developing T cells with a myriad of cell types are required for normal T cell development. Intercellular interactions of T cell precursors with endothelial cells, thymic epithelial cells, fibroblasts, thymic macrophages and dendritic cells are all mediated by adhesion molecules on immature T cells binding to ligands on thymic microenvironment cells. While many receptor-ligand interactions that are important in intrathymic T cell development are known, the adhesion molecules that are important for migration of T cell precursors to the thymus and for emigration of mature thymocytes from the thymus are poorly understood. An emerging concept is that select adhesion molecules at discrete stages of T cell maturation participate in and regulate the complex processes of T cell development. PMID:7693023

  2. 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

  3. 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

  4. MmuPV1 infection and tumor development of T cell-deficient mice is prevented by passively transferred hyperimmune sera from normal congenic mice immunized with MmuPV1 virus-like particles (VLPs).

    PubMed

    Joh, Joongho; Ghim, Shin-je; Chilton, Paula M; Sundberg, John P; Park, Jino; Wilcher, Sarah A; Proctor, Mary L; Bennett Jenson, A

    2016-02-01

    Infection by mouse papillomavirus (PV), MmuPV1, of T cell-deficient, B6.Cg-Foxn1(nu)/J nude mice revealed that four, distinct squamous papilloma phenotypes developed simultaneously after infection of experimental mice. Papillomas appeared on the muzzle, vagina, and tail at or about day 42days post-inoculation. The dorsal skin developed papillomas and hair follicle tumors (trichoblastomas) as early as 26days after infection. Passive transfer of hyperimmune sera from normal congenic mice immunized with MmuPV1 virus-like particles (VLPs) to T cell-deficient strains of mice prevented infection by virions of experimental mice. This study provides further evidence that T cell deficiency is critical for tumor formation by MmuPV1 infection. PMID:26778691

  5. γδ 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 γδ T cells, such that ∼80% of female B10.TCRδ(-/-) mice develop keratitis by 18 wk of age. In this article, we show that CD8(+) αβ T cells are the drivers of this disease, because adoptive transfer of CD8(+), but not CD4(+), T cells to keratitis-resistant B10.TCRβ/δ(-/-) hosts induced a high incidence of keratitis. This finding was unexpected because in other autoimmune diseases, more often CD4(+) αβ T cells, or both CD4(+) and CD8(+) αβ T cells, mediate the disease. Compared with wild-type B10 mice, B10.TCRδ(-/-) mice also show increased percentages of peripheral memory phenotype CD8(+) αβ T cells, along with an elevated frequency of CD8(+) αβ T cells biased to produce inflammatory cytokines. In addition, B10.TCRδ-/- mice have fewer peripheral CD4(+) CD25(+) Foxp3(+) αβ 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, γδ T cells are required to generate adequate numbers of CD4(+) CD25(+) Foxp3(+) Tregs, and that in B10.TCRδ(-/-) mice a Treg deficiency allows dysregulated effector or memory CD8(+) αβ T cells to infiltrate the cornea and provoke an autoimmune attack. PMID:26566677

  6. Extrathymic development of murine T cells after bone marrow transplantation

    PubMed Central

    Holland, Amanda M.; Zakrzewski, Johannes L.; Tsai, Jennifer J.; Hanash, Alan M.; Dudakov, Jarrod A.; Smith, Odette M.; West, Mallory L.; Singer, Natalie V.; Brill, Jessie; Sun, Joseph C.; van den Brink, Marcel R.M.

    2012-01-01

    Restoring T cell competence is a significant clinical challenge in patients whose thymic function is severely compromised due to age or cytoreductive conditioning. Here, we demonstrate in mice that mesenteric LNs (MLNs) support extrathymic T cell development in euthymic and athymic recipients of bone marrow transplantation (BMT). Furthermore, in aged murine BMT recipients, the contribution of the MLNs to the generation of T cells was maintained, while the contribution of the thymus was significantly impaired. Thymic impairment resulted in a proportional increase in extrathymic-derived T cell progenitors. Extrathymic development in athymic recipients generated conventional naive TCRαβ T cells with a broad Vβ repertoire and intact functional and proliferative potential. Moreover, in the absence of a functional thymus, immunity against known pathogens could be augmented using engineered precursor T cells with viral specificity. These findings demonstrate the potential of extrathymic T cell development for T cell reconstitution in patients with limited thymic function. PMID:23160195

  7. 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

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

    PubMed Central

    Stengel, Kristy R.; Zhao, Yue; Klus, Nicholas J.; Kaiser, Jonathan F.; Gordy, Laura E.; Joyce, Sebastian

    2015-01-01

    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 TCRβ-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 αβ 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

  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

    2015-11-01

    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 TCRβ-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 αβ 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. Microenvironmental cues for T-cell acute lymphoblastic leukemia development.

    PubMed

    Passaro, Diana; Quang, Christine Tran; Ghysdael, Jacques

    2016-05-01

    Intensive chemotherapy regimens have led to a substantial improvement in the cure rate of patients suffering from T-cell acute lymphoblastic leukemia (T-ALL). Despite this progress, about 15% and 50% of pediatric and adult cases, respectively, show resistance to treatment or relapse with dismal prognosis, calling for further therapeutic investigations. T-ALL is an heterogeneous disease, which presents intrinsic alterations leading to aberrant expression of transcription factors normally involved in hematopoietic stem/progenitor cell development and mutations in genes implicated in the regulation of cell cycle progression, apoptosis, and T-cell development. Gene expression profiling allowed the classification of T-ALL into defined molecular subgroups that mostly reflects the stage of their differentiation arrest. So far this knowledge has not translated into novel, targeted therapy. Recent evidence points to the importance of extrinsic signaling cues in controlling the ability of T-ALL to home, survive, and proliferate, thus offering the perspective of new therapeutic options. This review summarizes the present understanding of the interactions between hematopoietic cells and bone marrow/thymic niches during normal hematopoiesis, describes the main signaling pathways implicated in this dialog, and finally highlights how malignant T cells rely on specific niches to maintain their ability to sustain and propagate leukemia. PMID:27088913

  11. Removal of myeloid cytokines from the cellular environment enhances T-cell development in vitro.

    PubMed

    Smeets, Monique F M A; Mackenzie-Kludas, Charley; Mohtashami, Mahmood; Zhang, Hui-Hua; Zúñiga-Pflücker, Juan Carlos; Izon, David J

    2013-10-01

    The majority of T-cell development occurs in the thymus. Thymic epithelial cells are specialized cells that express NOTCH ligands and secrete specific cytokines required for normal T-cell lymphopoiesis. It has been demonstrated that OP9 cells derived from macrophage colony-stimulating factor (M-CSF)-deficient mice can support T-cell development when transduced with a NOTCH ligand, Delta-like 1 (Dll1). In this report, we have tested CSF-deficient mouse fibroblasts transduced with Dll1 for their ability to support T-cell differentiation. The data provided here demonstrate that CSF-deficient fibroblasts expressing DLL1 can support T-cell development. Indeed, co-cultures with these fibroblasts produced more T-cell progenitors compared with OP9-DL1 cultures. Addition of myeloid cytokines to OP9-DL1 co-cultures significantly inhibited T-cell development while CSF-deficient DLL1(+) fibroblasts retained partial T-cell differentiation. Taken together, these data imply that their lack of myeloid cytokines allows DLL1(+) fibroblasts to more efficiently generate T-cells. Development of this fibroblast system suggests that there is potential for generating human T-cell precursors via co-culture with human fibroblasts expressing DLL1 or DLL4. These T-cell precursors could be used for treating immunodeficient patients. PMID:23988615

  12. Thymic stromal cell subsets for T cell development.

    PubMed

    Nitta, Takeshi; Suzuki, Harumi

    2016-03-01

    The thymus provides a specialized microenvironment in which a variety of stromal cells of both hematopoietic and non-hematopoietic origin regulate development and repertoire selection of T cells. Recent studies have been unraveling the inter- and intracellular signals and transcriptional networks for spatiotemporal regulation of development of thymic stromal cells, mainly thymic epithelial cells (TECs), and the molecular mechanisms of how different TEC subsets control T cell development and selection. TECs are classified into two functionally different subsets: cortical TECs (cTECs) and medullary TECs (mTECs). cTECs induce positive selection of diverse and functionally distinct T cells by virtue of unique antigen-processing systems, while mTECs are essential for establishing T cell tolerance via ectopic expression of peripheral tissue-restricted antigens and cooperation with dendritic cells. In addition to reviewing the role of the thymic stroma in conventional T cell development, we will discuss recently discovered novel functions of TECs in the development of unconventional T cells, such as natural killer T cells and γδT cells. PMID:26825337

  13. mTORC2 in Thymic Epithelial Cells Controls Thymopoiesis and T Cell Development.

    PubMed

    Wang, Hong-Xia; Cheng, Joyce S; Chu, Shuai; Qiu, Yu-Rong; Zhong, Xiao-Ping

    2016-07-01

    Thymic epithelial cells (TECs) play important roles in T cell generation. Mechanisms that control TEC development and function are still not well defined. The mammalian or mechanistic target of rapamycin complex (mTORC)2 signals to regulate cell survival, nutrient uptake, and metabolism. We report in the present study that mice with TEC-specific ablation of Rictor, a critical and unique adaptor molecule in mTORC2, display thymic atrophy, which accompanies decreased TEC numbers in the medulla. Moreover, generation of multiple T cell lineages, including conventional TCRαβ T cells, regulatory T cells, invariant NKT cells, and TCRγδ T cells, was reduced in TEC-specific Rictor-deficient mice. Our data demonstrate that mTORC2 in TECs is important for normal thymopoiesis and efficient T cell generation. PMID:27233961

  14. Functional Development of the T Cell Receptor for Antigen

    PubMed Central

    Ebert, Peter J.R.; Li, Qi-Jing; Huppa, Johannes B.; Davis, Mark M.

    2016-01-01

    For over three decades now, the T cell receptor (TCR) for antigen has not ceased to challenge the imaginations of cellular and molecular immunologists alike. T cell antigen recognition transcends every aspect of adaptive immunity: it shapes the T cell repertoire in the thymus and directs T cell-mediated effector functions in the periphery, where it is also central to the induction of peripheral tolerance. Yet, despite its central position, there remain many questions unresolved: how can one TCR be specific for one particular peptide-major histocompatibility complex (pMHC) ligand while also binding other pMHC ligands with an immunologically relevant affinity? And how can a T cell’s extreme specificity (alterations of single methyl groups in their ligand can abrogate a response) and sensitivity (single agonist ligands on a cell surface are sufficient to trigger a measurable response) emerge from TCR–ligand interactions that are so low in affinity? Solving these questions is intimately tied to a fundamental understanding of molecular recognition dynamics within the many different contexts of various T cell–antigen presenting cell (APC) contacts: from the thymic APCs that shape the TCR repertoire and guide functional differentiation of developing T cells to the peripheral APCs that support homeostasis and provoke antigen responses in naïve, effector, memory, and regulatory T cells. Here, we discuss our recent findings relating to T cell antigen recognition and how this leads to the thymic development of foreign-antigen-responsive αβT cells. PMID:20800817

  15. Human Peripheral CD4(+) Vδ1(+) γδT Cells Can Develop into αβT Cells.

    PubMed

    Ziegler, Hendrik; Welker, Christian; Sterk, Marco; Haarer, Jan; Rammensee, Hans-Georg; Handgretinger, Rupert; Schilbach, Karin

    2014-01-01

    The lifelong generation of αβT cells enables us to continuously build immunity against pathogens and malignancies despite the loss of thymic function with age. Homeostatic proliferation of post-thymic naïve and memory T cells and their transition into effector and long-lived memory cells balance the decreasing output of naïve T cells, and recent research suggests that also αβT-cell development independent from the thymus may occur. However, the sites and mechanisms of extrathymic T-cell development are not yet understood in detail. γδT cells represent a small fraction of the overall T-cell pool, and are endowed with tremendous phenotypic and functional plasticity. γδT cells that express the Vδ1 gene segment are a minor population in human peripheral blood but predominate in epithelial (and inflamed) tissues. Here, we characterize a CD4(+) peripheral Vδ1(+) γδT-cell subpopulation that expresses stem-cell and progenitor markers and is able to develop into functional αβT cells ex vivo in a simple culture system and in vivo. The route taken by this process resembles thymic T-cell development. However, it involves the re-organization of the Vδ1(+) γδTCR into the αβTCR as a consequence of TCR-γ chain downregulation and the expression of surface Vδ1(+)Vβ(+) TCR components, which we believe function as surrogate pre-TCR. This transdifferentiation process is readily detectable in vivo in inflamed tissue. Our study provides a conceptual framework for extrathymic T-cell development and opens up a new vista in immunology that requires adaptive immune responses in infection, autoimmunity, and cancer to be reconsidered. PMID:25709606

  16. Normal T-cell turnover in sooty mangabeys harboring active simian immunodeficiency virus infection.

    PubMed

    Chakrabarti, L A; Lewin, S R; Zhang, L; Gettie, A; Luckay, A; Martin, L N; Skulsky, E; Ho, D D; Cheng-Mayer, C; Marx, P A

    2000-02-01

    Sooty mangabeys naturally infected with simian immunodeficiency virus (SIV) remain healthy though they harbor viral loads comparable to those in rhesus macaques that progress to AIDS. To assess the immunologic basis of disease resistance in mangabeys, we compared the effect of SIV infection on T-cell regeneration in both monkey species. Measurement of the proliferation marker Ki-67 by flow cytometry showed that mangabeys harbored proliferating T cells at a level of 3 to 4% in peripheral blood irrespective of their infection status. In contrast, rhesus macaques demonstrated a naturally high fraction of proliferating T cells (7%) that increased two- to threefold following SIV infection. Ki-67(+) T cells were predominantly CD45RA(-), indicating increased proliferation of memory cells in macaques. Quantitation of an episomal DNA product of T-cell receptor alpha rearrangement (termed alpha1 circle) showed that the concentration of recent thymic emigrants in blood decreased with age over a 2-log unit range in both monkey species, consistent with age-related thymic involution. SIV infection caused a limited decrease of alpha1 circle numbers in mangabeys as well as in macaques. Dilution of alpha1 circles by T-cell proliferation likely contributed to this decrease, since alpha1 circle numbers and Ki-67(+) fractions correlated negatively. These findings are compatible with immune exhaustion mediated by abnormal T-cell proliferation, rather than with early thymic failure, in SIV-infected macaques. Normal T-cell turnover in SIV-infected mangabeys provides an explanation for the long-term maintenance of a functional immune system in these hosts. PMID:10627531

  17. Bax alpha perturbs T cell development and affects cell cycle entry of T cells.

    PubMed Central

    Brady, H J; Gil-Gómez, G; Kirberg, J; Berns, A J

    1996-01-01

    Bax alpha can heterodimerize with Bcl-2 and Bcl-X(L), countering their effects, as well as promoting apoptosis on overexpression. We show that bax alpha transgenic mice have greatly reduced numbers of mature T cells, which results from an impaired positive selection in the thymus. This perturbation in positive selection is accompanied by an increase in the number of cycling thymocytes. Further to this, mature T cells overexpressing Bax alpha have lower levels of p27Kip1 and enter S phase more rapidly in response to interleukin-2 stimulation than do control T cells, while the converse is true of bcl-2 transgenic T cells. These data indicate that apoptotic regulatory proteins can modulate the level of cell cycle-controlling proteins and thereby directly impact on the cell cycle. Images PMID:9003775

  18. 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....

  19. Hydrophobic CDR3 residues promote the development of self-reactive T cells.

    PubMed

    Stadinski, Brian D; Shekhar, Karthik; Gómez-Touriño, Iria; Jung, Jonathan; Sasaki, Katsuhiro; Sewell, Andrew K; Peakman, Mark; Chakraborty, Arup K; Huseby, Eric S

    2016-08-01

    Studies of individual T cell antigen receptors (TCRs) have shed some light on structural features that underlie self-reactivity. However, the general rules that can be used to predict whether TCRs are self-reactive have not been fully elucidated. Here we found that the interfacial hydrophobicity of amino acids at positions 6 and 7 of the complementarity-determining region CDR3β robustly promoted the development of self-reactive TCRs. This property was found irrespective of the member of the β-chain variable region (Vβ) family present in the TCR or the length of the CDR3β. An index based on these findings distinguished Vβ2(+), Vβ6(+) and Vβ8.2(+) regulatory T cells from conventional T cells and also distinguished CD4(+) T cells selected by the major histocompatibility complex (MHC) class II molecule I-A(g7) (associated with the development of type 1 diabetes in NOD mice) from those selected by a non-autoimmunity-promoting MHC class II molecule I-A(b). Our results provide a means for distinguishing normal T cell repertoires versus autoimmunity-prone T cell repertoires. PMID:27348411

  20. Comparative proteomics of exosomes secreted by tumoral Jurkat T cells and normal human T cell blasts unravels a potential tumorigenic role for valosin-containing protein.

    PubMed

    Bosque, Alberto; Dietz, Lisa; Gallego-Lleyda, Ana; Sanclemente, Manuel; Iturralde, María; Naval, Javier; Alava, María Angeles; Martínez-Lostao, Luis; Thierse, Hermann-Josef; Anel, Alberto

    2016-05-17

    We have previously characterized that FasL and Apo2L/TRAIL are stored in their bioactive form inside human T cell blasts in intraluminal vesicles present in multivesicular bodies. These vesicles are rapidly released to the supernatant in the form of exosomes upon re-activation of T cells. In this study we have compared for the first time proteomics of exosomes produced by normal human T cell blasts with those produced by tumoral Jurkat cells, with the objective of identify proteins associated with tumoral exosomes that could have a previously unrecognized role in malignancy. We have identified 359 and 418 proteins in exosomes from T cell blasts and Jurkat cells, respectively. Interestingly, only 145 (around a 40%) are common. The major proteins in both cases are actin and tubulin isoforms and the common interaction nodes correspond to these cytoskeleton and related proteins, as well as to ribosomal and mRNA granule proteins. We detected 14 membrane proteins that were especially enriched in exosomes from Jurkat cells as compared with T cell blasts. The most abundant of these proteins was valosin-containing protein (VCP), a membrane ATPase involved in ER homeostasis and ubiquitination. In this work, we also show that leukemic cells are more sensitive to cell death induced by the VCP inhibitor DBeQ than normal T cells. Furthermore, VCP inhibition prevents functional exosome secretion only in Jurkat cells, but not in T cell blasts. These results suggest VCP targeting as a new selective pathway to exploit in cancer treatment to prevent tumoral exosome secretion. PMID:27086912

  1. The Effects of TLR Activation on T-Cell Development and Differentiation

    PubMed Central

    Jin, Bo; Sun, Tao; Yu, Xiao-Hong; Yang, Ying-Xiang; Yeo, Anthony E. T.

    2012-01-01

    Invading pathogens have unique molecular signatures that are recognized by Toll-like receptors (TLRs) resulting in either activation of antigen-presenting cells (APCs) and/or costimulation of T cells inducing both innate and adaptive immunity. TLRs are also involved in T-cell development and can reprogram Treg cells to become helper cells. T cells consist of various subsets, that is, Th1, Th2, Th17, T follicular helper (Tfh), cytotoxic T lymphocytes (CTLs), regulatory T cells (Treg) and these originate from thymic progenitor thymocytes. T-cell receptor (TCR) activation in distinct T-cell subsets with different TLRs results in differing outcomes, for example, activation of TLR4 expressed in T cells promotes suppressive function of regulatory T cells (Treg), while activation of TLR6 expressed in T cells abrogates Treg function. The current state of knowledge of regarding TLR-mediated T-cell development and differentiation is reviewed. PMID:22737174

  2. New insights on human T cell development by quantitative T cell receptor gene rearrangement studies and gene expression profiling

    PubMed Central

    Dik, Willem A.; Pike-Overzet, Karin; Weerkamp, Floor; de Ridder, Dick; de Haas, Edwin F.E.; Baert, Miranda R.M.; van der Spek, Peter; Koster, Esther E.L.; Reinders, Marcel J.T.; van Dongen, Jacques J.M.; Langerak, Anton W.; Staal, Frank J.T.

    2005-01-01

    To gain more insight into initiation and regulation of T cell receptor (TCR) gene rearrangement during human T cell development, we analyzed TCR gene rearrangements by quantitative PCR analysis in nine consecutive T cell developmental stages, including CD34+ lin− cord blood cells as a reference. The same stages were used for gene expression profiling using DNA microarrays. We show that TCR loci rearrange in a highly ordered way (TCRD-TCRG-TCRB-TCRA) and that the initiating Dδ2-Dδ3 rearrangement occurs at the most immature CD34+CD38−CD1a− stage. TCRB rearrangement starts at the CD34+CD38+CD1a− stage and complete in-frame TCRB rearrangements were first detected in the immature single positive stage. TCRB rearrangement data together with the PTCRA (pTα) expression pattern show that human TCRβ-selection occurs at the CD34+CD38+CD1a+ stage. By combining the TCR rearrangement data with gene expression data, we identified candidate factors for the initiation/regulation of TCR recombination. Our data demonstrate that a number of key events occur earlier than assumed previously; therefore, human T cell development is much more similar to murine T cell development than reported before. PMID:15928199

  3. B-cell antigens within normal and activated human T cells

    PubMed Central

    Sandilands, G P; Perry, M; Wootton, M; Hair, J; More, I A R

    1999-01-01

    In this study we compared cell surface staining for human peripheral blood lymphocyte (PBL) CD antigens by flow cytometry, with staining obtained following permeabilization of PBL using the Cytoperm method (Serotec). Six CD antigens (CD20, CD21, CD22, CD32, CD35 and major histocompatibility complex class II antigen) normally found on the surface of B cells, were also found to be expressed within T cells. We also showed, by immunoelectron microscopy, that these inappropriately expressed (‘occult’) CD antigens are located within cytoplasmic vesicles or within the rough endoplasmic reticulum. Following in vitro activation of T cells a distinct increase in expression of all of these cytoplasmic antigens was observed but staining at the cell surface was, by comparison, weak. We therefore propose that up-regulation of various B-cell CD antigens occurs within the cytoplasm of T cells following activation and that these antigens may be synthesized and released into the fluid-phase as soluble immunoregulatory molecules. PMID:10233724

  4. B-cell antigens within normal and activated human T cells.

    PubMed

    Sandilands, G P; Perry, M; Wootton, M; Hair, J; More, I A

    1999-03-01

    In this study we compared cell surface staining for human peripheral blood lymphocyte (PBL) CD antigens by flow cytometry, with staining obtained following permeabilization of PBL using the Cytoperm method (Serotec). Six CD antigens (CD20, CD21, CD22, CD32, CD35 and major histocompatibility complex class II antigen) normally found on the surface of B cells, were also found to be expressed within T cells. We also showed, by immunoelectron microscopy, that these inappropriately expressed ('occult') CD antigens are located within cytoplasmic vesicles or within the rough endoplasmic reticulum. Following in vitro activation of T cells a distinct increase in expression of all of these cytoplasmic antigens was observed but staining at the cell surface was, by comparison, weak. We therefore propose that up-regulation of various B-cell CD antigens occurs within the cytoplasm of T cells following activation and that these antigens may be synthesized and released into the fluid-phase as soluble immunoregulatory molecules. PMID:10233724

  5. SHARPIN controls the development of regulatory T cells.

    PubMed

    Redecke, Vanessa; Chaturvedi, Vandana; Kuriakose, Jeeba; Häcker, Hans

    2016-06-01

    SHARPIN is an essential component of the linear ubiquitin chain assembly complex (LUBAC) complex that controls signalling pathways of various receptors, including the tumour necrosis factor receptor (TNFR), Toll-like receptor (TLR) and antigen receptor, in part by synthesis of linear, non-degrading ubiquitin chains. Consistent with SHARPIN's function in different receptor pathways, the phenotype of SHARPIN-deficient mice is complex, including the development of inflammatory systemic and skin diseases, the latter of which depend on TNFR signal transduction. Given the established function of SHARPIN in primary and malignant B cells, we hypothesized that SHARPIN might also regulate T-cell receptor (TCR) signalling and thereby control T-cell biology. Here, we focus primarily on the role of SHARPIN in T cells, specifically regulatory T (Treg) cells. We found that SHARPIN-deficient (Sharpin(cpdm/cpdm) ) mice have significantly reduced numbers of FOXP3(+) Treg cells in lymphoid organs and the peripheral blood. Competitive reconstitution of irradiated mice with mixed bone marrow from wild-type and SHARPIN-deficient mice revealed an overall reduced thymus population with SHARPIN-deficient cells with almost complete loss of thymic Treg development. Consistent with this cell-intrinsic function of SHARPIN in Treg development, TCR stimulation of SHARPIN-deficient thymocytes revealed reduced activation of nuclear factor-κB and c-Jun N-terminal kinase, establishing a function of SHARPIN in TCR signalling, which may explain the defective Treg development. In turn, in vitro generation and suppressive activity of mature SHARPIN-deficient Treg cells were comparable to wild-type cells, suggesting that maturation, but not function, of SHARPIN-deficient Treg cells is impaired. Taken together, these findings show that SHARPIN controls TCR signalling and is required for efficient generation of Treg cells in vivo, whereas the inhibitory function of mature Treg cells appears to be

  6. Distinct p21 requirements for regulating normal and self-reactive T cells through IFN-γ production

    PubMed Central

    Daszkiewicz, Lidia; Vázquez-Mateo, Cristina; Rackov, Gorjana; Ballesteros-Tato, André; Weber, Kathrin; Madrigal-Avilés, Adrián; Di Pilato, Mauro; Fotedar, Arun; Fotedar, Rati; Flores, Juana M.; Esteban, Mariano; Martínez-A, Carlos; Balomenos, Dimitrios

    2015-01-01

    Self/non-self discrimination characterizes immunity and allows responses against pathogens but not self-antigens. Understanding the principles that govern this process is essential for designing autoimmunity treatments. p21 is thought to attenuate autoreactivity by limiting T cell expansion. Here, we provide direct evidence for a p21 role in controlling autoimmune T cell autoreactivity without affecting normal T cell responses. We studied C57BL/6, C57BL/6/lpr and MRL/lpr mice overexpressing p21 in T cells, and showed reduced autoreactivity and lymphadenopathy in C57BL/6/lpr, and reduced mortality in MRL/lpr mice. p21 inhibited effector/memory CD4+ CD8+ and CD4−CD8− lpr T cell accumulation without altering defective lpr apoptosis. This was mediated by a previously non-described p21 function in limiting T cell overactivation and overproduction of IFN-γ, a key lupus cytokine. p21 did not affect normal T cell responses, revealing differential p21 requirements for autoreactive and normal T cell activity regulation. The underlying concept of these findings suggests potential treatments for lupus and autoimmune lymphoproliferative syndrome, without compromising normal immunity. PMID:25573673

  7. Normal development.

    PubMed

    Girard, Nadine; Koob, Meriam; Brunel, Herv

    2016-01-01

    Numerous events are involved in brain development, some of which are detected by neuroimaging. Major changes in brain morphology are depicted by brain imaging during the fetal period while changes in brain composition can be demonstrated in both pre- and postnatal periods. Although ultrasonography and computed tomography can show changes in brain morphology, these techniques are insensitive to myelination that is one of the most important events occurring during brain maturation. Magnetic resonance imaging (MRI) is therefore the method of choice to evaluate brain maturation. MRI also gives insight into the microstructure of brain tissue through diffusion-weighted imaging and diffusion tensor imaging. Metabolic changes are also part of brain maturation and are assessed by proton magnetic resonance spectroscopy. Understanding and knowledge of the different steps in brain development are required to be able to detect morphologic and structural changes on neuroimaging. Consequently alterations in normal development can be depicted. PMID:27430460

  8. Egr3 Induces a Th17 Response by Promoting the Development of γδ T Cells

    PubMed Central

    Parkinson, Rose M.; Collins, Samuel L.; Horton, Maureen R.; Powell, Jonathan D.

    2014-01-01

    The transcription factor Early Growth Response 3 (Egr3) has been shown to play an important role in negatively regulating T cell activation and promoting T cell anergy in Th1 cells. However, its role in regulating other T helper subsets has yet to be described. We sought to determine the role of Egr3 in a Th17 response using transgenic mice that overexpress Egr3 in T cells (Egr3 TG). Splenocytes from Egr3 TG mice demonstrated more robust generation of Th17 cells even under non-Th17 skewing conditions. We found that while Egr3 TG T cells were not intrinsically more likely to become Th17 cells, the environment encountered by these cells was more conducive to Th17 development. Further analysis revealed a considerable increase in the number of γδ T cells in both the peripheral lymphoid organs and mucosal tissues of Egr3 TG mice, a cell type which normally accounts for only a small fraction of peripheral lymphocytes. Consistent with this marked increase in peripheral γδ T cells, thymocytes from Egr3 TG mice also appear biased toward γδ T cell development. Coculture of these Egr3-induced γδ T cells with wildtype CD4+ T cells increases Th17 differentiation, and Egr3 TG mice are more susceptible to bleomycin-induced lung inflammation. Overall our findings strengthen the role for Egr3 in promoting γδ T cell development and show that Egr3-induced γδ T cells are both functional and capable of altering the adaptive immune response in a Th17-biased manner. Our data also demonstrates that the role played by Egr3 in T cell activation and differentiation is more complex than previously thought. PMID:24475259

  9. 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.

  10. Foxo transcription factors control regulatory T cell development and function

    PubMed Central

    Kerdiles, Yann M.; Stone, Erica L.; Beisner, Daniel L.; McGargill, Maureen A.; Ch'en, Irene L.; Stockmann, Christian; Katayama, Carol D.; Hedrick, Stephen M.

    2010-01-01

    SUMMARY Foxo transcription factors integrate extrinsic signals to regulate cell division, differentiation and survival, and specific functions of lymphoid and myeloid cells. Here we showed the absence of Foxo1 severely curtailed the development of Foxp3+ regulatory T (Treg) cells, and those that developed were nonfunctional in vivo. The loss of function included diminished CTLA-4 receptor expression as the Ctla4 gene was a direct target of Foxo1. T cell specific loss of Foxo1 resulted in exocrine pancreatitis, hind limb paralysis, multi-organ lymphocyte infiltration, anti-nuclear antibodies and expanded germinal centers. Foxo-mediated control over Treg cell specification was further revealed by the inability of TGF-β cytokine to suppress T-bet transcription factor in the absence of Foxo1, resulting in IFN-γ-secretion. In addition the absence of Foxo3 exacerbated the effects of the loss of Foxo1. Thus, Foxo transcription factors guide the contingencies of T cell differentiation and specific functions of effector cell populations. PMID:21167754

  11. Molecular mechanisms of angioimmunoblastic T-cell lymphoma development.

    PubMed

    Sakata-Yanagimoto, Mamiko; Chiba, Shigeru

    2016-08-01

    The molecular pathogenesis of peripheral T-cell lymphoma (PTCL) has gradually been clarified in terms of genomic abnormalities. Insights into these genomic abnormalities have provided clues to understanding the pathogenesis of PTCL. Furthermore, the origins of lymphoma cells have been clarified by investigating the distribution of genomic abnormalities in tumor cells and non-tumor blood cells. Multistep tumorigenesis has been suggested to be a fundamental mechanism underlying the development of angioimmunoblastic T-cell lymphoma (AITL), a distinct subtype of PTCL: premalignant cells evolve from hematopoietic progenitors via mutations in epigenetic regulators. These cells then further differentiate into tumor cells via the addition of tumor-specific G17V RHOA mutations. Meanwhile, AITL are composed of various infiltrating cells as well as tumor cells. Most notably, AITL tissues are characterized by massive infiltration of B cells partially infected by Epstein-Barr virus, follicular dendritic cells, and high endothelial venules. Infiltration of these cell types has been thought to be a reactive process, promoted by cytokines and chemokines released from tumor cells. Considering the multistep mechanisms of AITL allows us to analyze whether these infiltrating cells are also derived from premalignant cells. Indeed, the mechanisms underlying massive infiltration of bystander cells might be more complicated than previously imagined. PMID:27599421

  12. 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

  13. Defect in recruiting effector memory CD8+ T-cells in malignant pleural effusions compared to normal pleural fluid

    PubMed Central

    2013-01-01

    Background Malignant pleural effusions (MPE) are a common and fatal complication in cancers including lung or breast cancers, or malignant pleural mesothelioma (MPM). MPE animal models and immunotherapy trials in MPM patients previously suggested defects of the cellular immunity in MPE. However only few observational studies of the immune response were done in MPM patients, using questionable control groups (transudate…). Methods We compared T cell populations evaluated by flow cytometry from blood and pleural effusion of untreated patients with MPM (n = 58), pleural metastasis of adenocarcinoma (n = 30) or with benign pleural lesions associated with asbestos exposure (n = 23). Blood and pleural fluid were also obtained from healthy subjects, providing normal values for T cell populations. Results Blood CD4+ or CD8+ T cells percentages were similar in all groups of patients or healthy subjects. Whereas pleural fluid from healthy controls contained mainly CD8+ T cells, benign or malignant pleural effusions included mainly CD4+ T cells. Effector memory T cells were the main T cell subpopulation in pleural fluid from healthy subjects. In contrast, there was a striking and selective recruitment of central memory CD4+ T cells in MPE, but not of effector cells CD8+ T cells or NK cells in the pleural fluid as one would expect in order to obtain an efficient immune response. Conclusions Comparing for the first time MPE to pleural fluid from healthy subjects, we found a local defect in recruiting effector CD8+ T cells, which may be involved in the escape of tumor cells from immune response. Further studies are needed to characterize which subtypes of effector CD8+ T cells are involved, opening prospects for cell therapy in MPE and MPM. PMID:23816056

  14. Metabolic Regulation of Regulatory T Cell Development and Function

    PubMed Central

    Coe, David John; Kishore, Madhav; Marelli-Berg, Federica

    2014-01-01

    It is now well established that the effector T cell (Teff) response is regulated by a series of metabolic switches. Quiescent T cells predominantly require adenosine triphosphate-generating processes, whereas proliferating Teff require high metabolic flux through growth-promoting pathways, such as glycolysis. Pathways that control metabolism and immune cell function are intimately linked, and changes in cell metabolism at both the cell and system levels have been shown to enhance or suppress specific T cell effector functions. Furthermore, functionally distinct T cell subsets require distinct energetic and biosynthetic pathways to support their specific functional needs. In particular, naturally occurring regulatory T cells (Treg) are characterized by a unique metabolic signature distinct to that of conventional Teff cells. We here briefly review the signaling pathways that control Treg metabolism and how this metabolic phenotype integrates their differentiation and function. Ultimately, these metabolic features may provide new opportunities for the therapeutic modulation of unwanted immune responses. PMID:25477880

  15. Coupling of the cell cycle and apoptotic machineries in developing T cells.

    PubMed

    Xue, Ling; Sun, Yuefang; Chiang, Leslie; He, Bo; Kang, Chulho; Nolla, Hector; Winoto, Astar

    2010-03-01

    Proliferation and apoptosis are diametrically opposite processes. Expression of certain genes like c-Myc, however, can induce both, pointing to a possible linkage between them. Developing CD4(+)CD8(+) thymocytes are intrinsically sensitive to apoptosis, but the molecular basis is not known. We have found that these noncycling cells surprisingly express many cell cycle proteins. We generated transgenic mice expressing a CDK2 kinase-dead (CDK2-DN) protein in the T cell compartment. Analysis of these mice showed that the CDK2-DN protein acts as a dominant negative mutant in mature T cells as expected, but surprisingly, it acts as a dominant active protein in CD4(+)CD8(+) thymocytes. The levels of CDK2 kinase activity, cyclin E, cyclin A, and other cell cycle proteins in transgenic CD4(+)CD8(+) thymocytes are increased. Concurrently, caspase levels are elevated, and apoptosis is significantly enhanced in vitro and in vivo. E2F-1, the unique E2F member capable of inducing apoptosis when overexpressed, is specifically up-regulated in transgenic CD4(+)CD8(+) thymocytes but not in other T cell populations. These results demonstrate that the cell cycle and apoptotic machineries are normally linked, and expression of cell cycle proteins in developing T cells contributes to their inherent 1sensitivity to apoptosis. PMID:20068041

  16. Transcriptional regulation of early T-cell development in the thymus.

    PubMed

    Seo, Wooseok; Taniuchi, Ichiro

    2016-03-01

    T-cell development occurs in multipotent progenitors arriving in the thymus, which provides a highly specialized microenvironment. Specification and sequential commitment processes to T cells begin in early thymic progenitors upon receiving thymus-specific environmental cues, resulting in the activation of the genetically programmed transcriptional cascade that includes turning on and off numerous transcription factors in a precise manner. Thus, early thymocyte differentiation has been an excellent model system to study cell differentiation processes. This review summarizes recent advances in our knowledge on thymic T-cell development from newly arrived multipotent T-cell progenitors to fully committed T-cell precursors, from the transcriptional regulation perspective. PMID:26763078

  17. Differential function of Themis CABIT domains during T cell development.

    PubMed

    Okada, Toshiyuki; Nitta, Takeshi; Kaji, Kentaro; Takashima, Akiko; Oda, Hiroyo; Tamehiro, Norimasa; Goto, Motohito; Okamura, Tadashi; Patrick, Michael S; Suzuki, Harumi

    2014-01-01

    Themis (also named Gasp) is a newly identified Grb2-binding protein that is essential for thymocyte positive selection. Despite the possible involvement of Themis in TCR-mediated signal transduction, its function remains unresolved and controversial. Themis contains two functionally uncharacterized regions called CABIT (cysteine-containing, all-β in Themis) domains, a nuclear localization signal (NLS), and a proline-rich sequence (PRS). To elucidate the role of these motifs in Themis's function in vivo, we established a series of mutant Themis transgenic mice on a Themis(-/-) background. Deletion of the highly conserved Core motif of CABIT1 or CABIT2 (Core1 or Core2, respectively), the NLS, or the PRS abolished Grb2-association, as well as TCR-dependent tyrosine-phosphorylation and the ability to induce positive selection in the thymus. The NLS and Core1 motifs were required for the nuclear localization of Themis, whereas Core2 and PRS were not. Furthermore, expression of ΔCore1- but not ΔCore2-Themis conferred dominant negative-type inhibition on T cell development. Collectively, our current results indicate that PRS, NLS, CABIT1, and CABIT2 are all required for positive selection, and that each of the CABIT domains exerts distinct functions during positive selection. PMID:24586531

  18. 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...

  19. Flow cytometric analysis of the stimulatory response of T cell subsets from normal and HIV-1+ individuals to various mitogenic stimuli in vitro.

    PubMed Central

    Medina, E; Borthwick, N; Johnson, M A; Miller, S; Bofill, M

    1994-01-01

    A novel technique is described which allows the study of the responses of T cell subpopulations stimulated in bulk cultures without interfering with cell-cell interactions. The number and phenotype of lymphoblasts developing following stimulation with phytohaemagglutinin (PHA), anti-CD3, staphylococcal protein A (SPA) and pokeweed mitogen (PWM) was determined in HIV-1- and HIV-1+ patients using a new five-parameter flow cytometric method. We found that normal T cells responded faster to PHA than to any of the other mitogens tested. The peak of the PHA response occurred on day 3, followed by anti-CD3 and SPA on day 4 and PWM mitogen on day 5. Although PHA and anti-CD3 stimulated up to 95% and 80% of lymphocytes, respectively, SPA and PWM stimulated only 40% and 30% of cells, respectively. A defective T cell response was observed in lymphocytes cultured from asymptomatic HIV-1+ patients compared with negative controls. This loss of response was related to a selective mortality of T cells following mitogenic stimulation, referred to as activation-associated lymphocyte death (AALD). The results showed that stronger mitogens (PHA and anti-CD3) induced AALD in a larger proportion (50-60%) of T cells than weaker mitogens such as SPA and PWM (30-40%), and that AALD affected different lymphocyte subsets to different extents. AALD occurred more frequently in total CD8+ and CD45RO+ T cells compared with CD4+ and CD45RA+ T cells, but memory CD4+ T cells were the population most severely affected in samples from HIV-1+ donors. PMID:7914156

  20. FOXP3+ regulatory T cell development and function require histone/protein deacetylase 3

    PubMed Central

    Wang, Liqing; Liu, Yujie; Han, Rongxiang; Beier, Ulf H.; Bhatti, Tricia R.; Akimova, Tatiana; Greene, Mark I.; Hiebert, Scott W.; Hancock, Wayne W.

    2015-01-01

    Treg dysfunction is associated with a variety of inflammatory diseases. Treg populations are defined by expression of the oligomeric transcription factor FOXP3 and inability to produce IL-2, a cytokine required for T cell maintenance and survival. FOXP3 activity is regulated post-translationally by histone/protein acetyltransferases and histone/protein deacetylases (HDACs). Here, we determined that HDAC3 mediates both the development and function of the two main Treg subsets, thymus-derived Tregs and induced Tregs (iTregs). We determined that HDAC3 and FOXP3 physically interact and that HDAC3 expression markedly reduces Il2 promoter activity. In murine models, conditional deletion of Hdac3 during thymic Treg development restored Treg production of IL-2 and blocked the suppressive function of Tregs. HDAC3-deficient mice died from autoimmunity by 4–6 weeks of age; however, injection of WT FOXP3+ Tregs prolonged survival. Adoptive transfer of Hdac3-deficient Tregs, unlike WT Tregs, did not control T cell proliferation in naive mice and did not prevent allograft rejection or colitis. HDAC3 also regulated the development of iTregs, as HDAC3-deficient conventional T cells were not converted into iTregs under polarizing conditions and produced large amounts of IL-2, IL-6, and IL-17. We conclude that HDAC3 is essential for the normal development and suppressive functions of thymic and peripheral FOXP3+ Tregs. PMID:25642770

  1. 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.

  2. MUC1 (CD227) interacts with lck tyrosine kinase in Jurkat lymphoma cells and normal T cells.

    PubMed

    Mukherjee, P; Tinder, T L; Basu, G D; Gendler, S J

    2005-01-01

    MUC1 (CD227) is a large transmembrane epithelial mucin glycoprotein, which is aberrantly overexpressed in most adenocarcinomas and is a target for immune therapy for epithelial tumors. Recently, MUC1 has been detected in a variety of hematopoietic cell malignancies including T and B cell lymphomas and myelomas; however, its function in these cells is not clearly defined. Using the Jurkat T cell lymphoma cell line and normal human T cells, we demonstrate that MUC1 is not only expressed in these cells but is also phosphorylated upon T cell receptor (TCR) ligation and associates with the Src-related T cell tyrosine kinase, p56lck. Upon TCR-mediated activation of Jurkat cells, MUC1 is found in the low-density membrane fractions, where linker of T cell activation is contained. Abrogation of MUC1 expression in Jurkat cells by MUC1-specific small interfering RNA resulted in defects in TCR-mediated downstream signaling events associated with T cell activation. These include reduction in Ca2+ influx and extracellular signal-regulated kinase 1/2 phosphorylation, leading to a decrease in CD69 expression, proliferation, and interleukin-2 production. These results suggest a regulatory role of MUC1 in modulating proximal signal transduction events through its interaction with proteins of the activation complex. PMID:15513966

  3. 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.

  4. 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

  5. High-affinity FRβ-specific CAR T cells eradicate AML and normal myeloid lineage without HSC toxicity.

    PubMed

    Lynn, R C; Feng, Y; Schutsky, K; Poussin, M; Kalota, A; Dimitrov, D S; Powell, D J

    2016-06-01

    Acute myeloid leukemia (AML) is an aggressive malignancy, and development of new treatments to prolong remissions is warranted. Chimeric antigen receptor (CAR) T-cell therapies appear promising but on-target, off-tumor recognition of antigen in healthy tissues remains a concern. Here we isolated a high-affinity (HA) folate receptor beta (FRβ)-specific single-chain variable fragment (2.48 nm KD) for optimization of FRβ-redirected CAR T-cell therapy for AML. T cells stably expressing the HA-FRβ CAR exhibited greatly enhanced antitumor activity against FRβ(+) AML in vitro and in vivo compared with a low-affinity FRβ CAR (54.3 nm KD). Using the HA-FRβ immunoglobulin G, FRβ expression was detectable in myeloid-lineage hematopoietic cells; however, expression in CD34(+) hematopoietic stem cells (HSCs) was nearly undetectable. Accordingly, HA-FRβ CAR T cells lysed mature CD14(+) monocytes, while HSC colony formation was unaffected. Because of the potential for elimination of mature myeloid lineage, mRNA CAR electroporation for transient CAR expression was evaluated. mRNA-electroporated HA-FRβ CAR T cells retained effective antitumor activity in vitro and in vivo. Together, our results highlight the importance of antibody affinity in target protein detection and CAR development and suggest that transient delivery of potent HA-FRβ CAR T cells is highly effective against AML and reduces the risk for long-term myeloid toxicity. PMID:26898190

  6. Canine CD4(+)CD8(+) double-positive T cells can develop from CD4(+) and CD8(+) T cells.

    PubMed

    Bismarck, Doris; Moore, Peter F; Alber, Gottfried; von Buttlar, Heiner

    2014-12-15

    For a long time the expression of the CD4 and CD8 receptor on peripheral blood T cells was thought to be mutually exclusive. However, in canine peripheral blood, similar to other species as swine or human for example, mature CD4(+)CD8(+) double-positive (dp) T cells exist which simultaneously express both surface receptors and have features of activated T cells. Canine CD4(+)CD8(+)dp T cells are heterogeneous and can be divided into three subpopulations by their intensity of CD4 and CD8α expression: CD4(bright)CD8α(bright), CD4(dim)CD8α(bright) and CD4(dim)CD8α(dim). The number of CD4(+)CD8α(+)dp T cells increases after in vitro stimulation of canine peripheral blood mononuclear cells (PBMC) raising the question of their progenitor(s). Thus, the aim of our study was to characterize the progenitor(s) of canine CD4(+)CD8α(+)dp T cells. By cell tracing experiments we identified both CD4(+) single-positive (sp) and also CD8α(+)sp T cells as progenitors of canine CD4(+)CD8α(+)dp T cells after in vitro stimulation. CD4(+)sp T cells almost exclusively upregulate a CD8αα homodimer, whereas CD8α(+)sp T cells can become CD4(+)CD8αβ(+) or CD4(+)CD8αα(+). Even in the absence of other cells, highly purified CD4(+)sp T cells can become double-positive upon in vitro stimulation, whereas highly purified CD8α(+)sp T cells fail to do so. However, CD8α(+)sp T cells can additionally express CD4 when stimulated in the presence of CD4(-)CD8α(-) double-negative (dn) cells or more efficiently when stimulated in the presence of CD4(+)sp T cells. Soluble factors secreted by CD4(+)sp T cells are sufficient for the upregulation of CD4 on CD8α(+)sp T cells, but direct cell-cell contact between CD4(+)sp and CD8α(+)sp T cells is more efficient. mRNA analysis shows that additional CD4 expression on CD8α(+)sp T cells results from de novo synthesis. Thus, uptake of soluble CD4 or trogocytosis is less likely as mechanism for generation of canine double-positive T cells. CD4(+)CD

  7. Role of Prolactin in the Recovered T-Cell Development of Early Partially Decapitated Chicken Embryo

    PubMed Central

    Moreno, J.; Varas, A.; Vicente, A.

    1998-01-01

    Although different experimental approaches have suggested certain regulation of the mammalian immune system by the neuroendocrine system, the precise factors involved in the process are largely unknown. In previous reports, we demonstrated important changes in the thymic development of chickens deprived of the major neuroendocrine centers by the removal of embryonic prosencephalon at 33-38 hr of incubation (DCx embryos) (Herradón et al., 1991; Moreno et al., 1995). In these embryos, there was a stopping of T-cell maturation that resulted in an accumulation of the most immature T-cell subsets (CD4-CD8- cells and CD4-CD81o cells) and, accordingly, in decreased numbers of DP (CD4+CD8+) thymocytes and mature CD3+TcRαβ + cells, but not CD3+TcRγδ lymphocytes. In the present work, we restore the thymic histology as well as the percentage of distinct T-cell subsets of DCx embryos by supplying recombinant chicken prolactin, grafting of embryonic pituitary gland, or making cephalic chick-quail chimeras. The recovery was not, however, whole and the percentage of CD3+TcRαβ thymocytes did not reach the normal values observed in 17-day-old control Sham-DCx embryos. The results are discussed on the basis of a key role for prolactin in chicken T-cell maturation. This hormone could regulate the transition of DN (CD4-CD8-) thymocytes to the DP (CD4+CD8+) cell compartment through its capacity for inducing IL-2 receptor expression on the former. PMID:9851358

  8. Differential expression of T cell antigens in normal peripheral blood lymphocytes: a quantitative analysis by flow cytometry.

    PubMed Central

    Ginaldi, L; Farahat, N; Matutes, E; De Martinis, M; Morilla, R; Catovsky, D

    1996-01-01

    AIMS: To obtain reference values of the level of expression of T cell antigens on normal lymphocyte subsets in order to disclose differences which could reflect their function or maturation stages, or both. METHODS: Peripheral blood from 15 healthy donors was processed by flow cytometry with triple colour analysis. For each sample phycoerythrin (PE) conjugated CD2, CD4, CD5, CD8, and CD56 monoclonal antibodies were combined with Cy5-R-phycoerythrin (TC) conjugated CD3 and fluorescein isothiocyanate (FITC) conjugated CD7; CD2- and CD7-PE were also combined with CD3-TC and CD4-FITC. Standard microbeads with different capacities to bind mouse immunoglobulins were used to convert the mean fluorescence intensity (MFI) values of the lymphocyte subsets identified by multiparametric flow cytometry into the number of antigen molecules per cell, measured as antibody binding capacity (ABC). RESULTS: CD4+ (helper/inducer) T cells exhibit a higher CD3 antigen expression compared with CD8+ (suppressor/ cytotoxic) T lymphocytes. Within the CD4+ T cells, the CD4+CD7- subset expressed a lower level of CD3 compared with CD4+CD7+ and CD8+CD7+ cells, and higher CD2 and CD5 expression than the main CD3+CD7+ subset. Major differences in antigen expression were also detected between CD3+ T cells and CD3-CD56+ natural killer (NK) cells: NK cells exhibited higher levels of CD7 and CD56 and lower levels of CD2 and CD5 than T cells. Significantly lower CD5 expression was also detected in the small CD5+ B lymphocyte subset compared with T cells. CONCLUSIONS: Quantitative flow cytometry with triple colour analysis may be used to detect antigen modulations in disease states and to increase the accuracy of diagnosis by comparison with findings in normal counterparts. Images PMID:8813949

  9. Specificity for the tumor-associated self-antigen WT1 drives the development of fully functional memory T cells in the absence of vaccination.

    PubMed

    Pospori, Constandina; Xue, Shao-An; Holler, Angelika; Voisine, Cecile; Perro, Mario; King, Judith; Fallah-Arani, Farnaz; Flutter, Barry; Chakraverty, Ronjon; Stauss, Hans J; Morris, Emma C

    2011-06-23

    Recently, vaccines against the Wilms Tumor antigen 1 (WT1) have been tested in cancer patients. However, it is currently not known whether physiologic levels of WT1 expression in stem and progenitor cells of normal tissue result in the deletion or tolerance induction of WT1-specific T cells. Here, we used an human leukocyte antigen-transgenic murine model to study the fate of human leukocyte antigen class-I restricted, WT1-specific T cells in the thymus and in the periphery. Thymocytes expressing a WT1-specific T-cell receptor derived from high avidity human CD8 T cells were positively selected into the single-positive CD8 population. In the periphery, T cells specific for the WT1 antigen differentiated into CD44-high memory phenotype cells, whereas T cells specific for a non-self-viral antigen retained a CD44(low) naive phenotype. Only the WT1-specific T cells, but not the virus-specific T cells, displayed rapid antigen-specific effector function without prior vaccination. Despite long-term persistence of WT1-specific memory T cells, the animals did not develop autoimmunity, and the function of hematopoietic stem and progenitor cells was unimpaired. This is the first demonstration that specificity for a tumor-associated self-antigen may drive differentiation of functionally competent memory T cells. PMID:21447831

  10. Metabolic control of regulatory T cell development and function.

    PubMed

    Zeng, Hu; Chi, Hongbo

    2015-01-01

    Foxp3(+) regulatory T cells (Tregs) maintain immune tolerance and play an important role in immunological diseases and cancers. Recent studies have revealed an intricate relationship between Treg biology and host and microbial metabolism. Various metabolites or nutrients produced by host and commensal microbes, such as vitamins and short-chain fatty acids (SCFAs), regulate Treg generation, trafficking, and function. Furthermore, cell intrinsic metabolic programs, orchestrated by mTOR and other metabolic sensors, modulate Foxp3 induction and Treg suppressive activity. Conversely, Tregs are crucial in regulating obesity-associated inflammation and host metabolic balance, and in shaping homeostasis of gut microbiota. We review here the interplay between Tregs and metabolism, with a particular focus on how host, commensal, and cellular metabolism impinge upon Treg homeostasis and function. PMID:25248463

  11. Dysregulation of CD30+ T cells by leukemia impairs isotype switching in normal B cells

    PubMed Central

    Cerutti, Andrea; Kim, Edmund C.; Shah, Shefali; Schattner, Elaine J.; Zan, Hong; Schaffer, András; Casali, Paolo

    2015-01-01

    Chronic lymphocytic leukemia (CLL) is associated with impaired immunoglobulin (Ig) class-switching from IgM to IgG and IgA, a defect that leads to recurrent infections. When activated in the presence of leukemic CLL B cells, T cells rapidly up-regulate CD30 through an OX40 ligand and interleukin 4 (IL-4)–dependent mechanism. These leukemia-induced CD30+ T cells inhibit CD40 ligand (CD40L)-mediated Sµ→Sγ and Sµ→Sα class-switch DNA recombination (CSR) by engaging CD30 ligand (CD30L), a molecule that interferes with the assembly of the CD40–tumor necrosis factor receptor–associated factor (TRAF) complex in nonmalignant IgD+ B cells. In addition, engagement of T cell CD30 by CD30L on neoplastic CLL B cells down-regulates the CD3-induced expression of CD40L. These findings indicate that, in CLL, abnormal CD30-CD30L interaction impairs IgG and IgA production by interfering with the CD40-mediated differentiation of nonmalignant B cells. PMID:11175813

  12. High affinity FRβ-specific CAR T cells eradicate AML and normal yeloid lineage without HSC toxicity

    PubMed Central

    Lynn, Rachel C; Feng, Yang; Schutsky, Keith; Poussin, Mathilde; Kalota, Anna; Dimitrov, Dimiter S; Powell, Daniel J

    2016-01-01

    Acute myeloid leukemia (AML) is an aggressive malignancy, and development of new treatments to prolong remissions is warranted. Chimeric antigen receptor (CAR) T-cell therapies appear promising but on-target, off-tumor recognition of antigen in healthy tissues remains a concern. Here, we isolated a high affinity (HA) folate receptor beta (FRβ)-specific scFv (2.48nM KD) for optimization of FRβ-redirected CAR T-cell therapy for AML. T-cells stably expressing the HA-FRβ CAR exhibited greatly enhanced antitumor activity against FRβ+ AML in vitro and in vivo compared to a low affinity (LA) FRβ CAR (54.3nM KD). Using the HA-FRβ IgG, FRβ expression was detectable in myeloid-lineage hematopoietic cells; however, expression in CD34+ hematopoietic stem cells (HSCs) was nearly undetectable. Accordingly, HA-FRβ CAR T-cells lysed mature CD14+ monocytes, while HSC colony formation was unaffected. Because of the potential for elimination of mature myeloid lineage, mRNA CAR electroporation for transient CAR expression was evaluated. mRNA-electroporated HA-FRβ CAR T-cells retained effective anti-tumor activity in vitro and in vivo. Together, our results highlight the importance of antibody affinity in target protein detection and CAR development and suggest that transient delivery of potent HA-FRβ CAR T-cells is highly effective against AML and reduces the risk for long-term myeloid toxicity. PMID:26898190

  13. 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.

  14. 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

  15. T cell acute lymphoblastic leukaemia presenting with sudden onset right oculomotor nerve palsy with normal neuroradiography and cerebrospinal fluid studies

    PubMed Central

    Bhatt, Vijaya Raj; Naqi, Muniba; Bartaula, Rajiv; Murukutla, Srujitha; Misra, Sulagna; Popalzai, Muhammad; Paramanathan, Kavitha; Dai, Qun

    2012-01-01

    Leptomeningeal disease presenting with neurological dysfunction is not uncommon in leukaemia. However, it is often accompanied by abnormalities in cerebrospinal fluid (CSF) studies and/or neuroradiography. Here, the authors describe a case of a young patient presenting with sudden onset right oculomotor nerve palsy with normal neuroradiography and CSF studies, who was subsequently diagnosed to have T cell acute lymphoblastic leukaemia (T-ALL). This case highlights that neurological manifestations can be the initial presenting feature of T-ALL and can occur suddenly despite normal neuroradiography and initial CSF studies. PMID:22605802

  16. Altered Development of NKT Cells, γδ T Cells, CD8 T Cells and NK Cells in a PLZF Deficient Patient

    PubMed Central

    Beaulieu, Aimee M.; Zaidi, Bushra; Carsons, Steven E.; Crow, Peggy K.; Yuan, Jianda; Wolchok, Jedd D.; Horsthemke, Bernhard; Wieczorek, Dagmar; Sant'Angelo, Derek B.

    2011-01-01

    In mice, the transcription factor, PLZF, controls the development of effector functions in invariant NKT cells and a subset of NKT cell-like, γδ T cells. Here, we show that in human lymphocytes, in addition to invariant NKT cells, PLZF was also expressed in a large percentage of CD8+ and CD4+ T cells. Furthermore, PLZF was also found to be expressed in all γδ T cells and in all NK cells. Importantly, we show that in a donor lacking functional PLZF, all of these various lymphocyte populations were altered. Therefore, in contrast to mice, PLZF appears to control the development and/or function of a wide variety of human lymphocytes that represent more than 10% of the total PBMCs. Interestingly, the PLZF-expressing CD8+ T cell population was found to be expanded in the peripheral blood of patients with metastatic melanoma but was greatly diminished in patients with autoimmune disease. PMID:21915328

  17. 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.

  18. 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

  19. Histamine type I (H/sub 1/) receptor radioligand binding studies on normal T cell subsets, B cells, and monocytes

    SciTech Connect

    Cameron, W.; Doyle, K.; Rocklin, R.E.

    1986-03-15

    A single, specific binding site for (/sup 3/H)pyrilamine on normal human T helper, T suppressor, B cells, and monocytes was documented. The binding of the radioligand to its receptor is reversible with cold H/sub 1/ antagonist, saturates at 40 to 60 nM, and binding equilibrium is achieved in 2 to 4 min. Using a computer program (Ligand), the authors calculated the dissociation constants, binding capacities, and numbers of receptors per cell for each of the different cell types. Monocytes were found to have the highest affinity for (/sup 3/H)pyrilamine, followed by T helper cells, B cells and T suppressor cells (K/sub D/ = 44.6 +/- 49.4 nM). T suppressor cells were found to express the higher number of H/sub 1/ receptors per cell followed by B cells, T helper cells, and monocytes. The binding affinity for (/sup 3/H)pyrilamine increased over a 48-hr period, whereas the number of receptors per T cell was essentially unchanged. In contrast, T cells stimulated with Con A or PHA were shown to have a greater than fourfold increase in the number of receptors per cell, whereas the binding affinity for (/sup 3/H)pyrilamine decreased over the 48-hr period. Although the function of H/sub 1/ receptors on T cells, B cells, and monocytes has not been completely defined, this receptor has the potential of playing an important role in the modulating the immune response.

  20. KSHV viral cyclin interferes with T-cell development and induces lymphoma through Cdk6 and Notch activation in vivo

    PubMed Central

    Pekkonen, Pirita; Järviluoma, Annika; Zinovkina, Nadezhda; Cvrljevic, Anna; Prakash, Sonam; Westermarck, Jukka; Evan, Gerard I; Cesarman, Ethel; Verschuren, Emmy W; Ojala, Päivi M

    2014-01-01

    Kaposi's sarcoma herpesvirus (KSHV)-encoded v-cyclin, a homolog of cellular cyclin D2, activates cellular CDK6, promotes G1-S transition of the cell cycle, induces DNA damage, apoptosis, autophagy and is reported to have oncogenic potential. Here we show that in vivo expression of v-cyclin in the B- and T-cell lymphocyte compartments results in a markedly low survival due to high penetrance of early-onset T-cell lymphoma and pancarditis. The v-cyclin transgenic mice have smaller pre-tumorigenic lymphoid organs, showing decreased cellularity, and increased proliferation and apoptosis. Furthermore, v-cyclin expression resulted in decreased amounts of CD3-expressing mature T-cells in the secondary lymphoid organs concurrent with alterations in the T-cell subpopulations of the thymus. This suggests that v-cyclin interferes with normal T-cell development. As the Notch pathway is recognized for its role in both T-cell development and lymphoma initiation, we addressed the role of Notch in the v-cyclin-induced alterations. Fittingly, we demonstrate induction of Notch3 and Hes1 in the pre-tumorigenic thymi and lymphomas of v-cyclin expressing mice, and show that lymphoma growth and viability are dependent on activated Notch signaling. Notch3 transcription and growth of the lymphomas was dependent on CDK6, as determined by silencing of CDK6 expression or chemical inhibition, respectively. Our work here reveals a viral cyclin-CDK6 complex as an upstream regulator of Notch receptor, suggesting that cyclins can play a role in the initiation of Notch-dependent lymphomagenesis. PMID:25483078

  1. 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

  2. Nippostrongylus brasiliensis can induce B7-independent antigen-specific development of IL-4-producing T cells from naive CD4 T cells in vivo.

    PubMed

    Liu, Zhugong; Liu, Qian; Pesce, John; Whitmire, Jeannette; Ekkens, Melinda J; Foster, Anthony; VanNoy, Jansie; Sharpe, Arlene H; Urban, Joseph F; Gause, William C

    2002-12-15

    Th2 immune responses to a number of infectious pathogens are dependent on B7-1/B7-2 costimulatory molecule interactions. We have now examined the Th2 immune response to Nippostrongylus brasiliensis (Nb) in B7-1/B7-2(-/-) mice and show that Th2 effector cells develop that can mediate worm expulsion and produce substantial Th2 cytokines comparable with wild-type infected mice; however, in marked contrast, B cell Ag-specific Ab production is abrogated after B7 blockade. To examine the mechanism of T cell activation, OVA-specific DO11.10 T cells were transferred to recipient mice, which were then immunized with a combination of Nb plus OVA or either alone. Only the combination of Nb plus OVA triggered T cell differentiation to OVA-specific Th2 cells, suggesting that Nb acts as an adjuvant to stimulate Ag-specific naive T cells to differentiate to effector Th2 cells. Furthermore, using the DO11.10 TCR-transgenic T cell adoptive transfer model, we show that blocking B7-1/B7-2 interactions does not impair nonparasite Ag-specific DO11.10 Th2 cell differentiation; however, DO11.10 T cell cycle progression and migration to the B cell zone are inhibited. PMID:12471130

  3. 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

  4. T Cells

    MedlinePlus

    ... or turn off the immune response. Cytotoxic or “killer” T cells directly attack and destroy cells bearing ... involve selective activation of helper T cells and killer T cells, with a corresponding decrease in regulatory ...

  5. T cell genetic background determines default T helper phenotype development in vitro

    PubMed Central

    1995-01-01

    A host's ability to resist certain pathogens such as Leishmania major can depend upon the phenotype of T helper (Th) subset that develops. Different murine genetic backgrounds are known to significantly alter the direction of Th subset development, although the cellular basis of this influence is poorly understood. To examine the basis of this effect we used an in vitro alpha/beta-T cell receptor (TCR) transgenic system for analysis of Th phenotype development. To control for TCR usage, we derived the DO11.10 alpha/beta-TCR transgene in several genetic backgrounds. Our findings suggest that the effects of genetic background on Th phenotype development reside within the T cell, and not the antigen-presenting cell compartment. Transgenic T cells from both the B10.D2 and BALB/c backgrounds showed development toward either the Th1 or Th2 phenotype under the strong directing influence of interleukin (IL) 12 and IL4, respectively. However, when T cells were activated in vitro under neutral conditions in which exogenous cytokines were not added, B10.D2-derived T cells acquired a significantly stronger Th1 phenotype than T cells from the BALB/c background, correspondent with in vivo Th responses to Leishmania in these strains. Importantly, these cytokine differences resulted in distinct functional properties, because B10.D2- but not BALB/c-derived T cells could induce macrophage production of nitric oxide, an important antimicrobial factor. Thus, the genetically determined default Th phenotype development observed in vitro may correspond to in vivo Th subset responses for pathogens such as Leishmania which do not initiate strong Th phenotype-directing signals. PMID:7836924

  6. Idh1 mutations contribute to the development of T-cell malignancies in genetically engineered mice

    PubMed Central

    Hao, Zhenyue; Cairns, Rob A.; Inoue, Satoshi; Li, Wanda Y.; Sheng, Yi; Lemonnier, François; Wakeham, Andrew; Snow, Bryan E.; Dominguez-Brauer, Carmen; Ye, Jing; Larsen, Dana M.; Straley, Kimberly S.; Tobin, Erica R.; Narayanaswamy, Rohini; Gaulard, Philippe; Mak, Tak W.

    2016-01-01

    Gain-of-function mutations in isocitrate dehydrogenase 1 (IDH1) are key drivers of hematopoietic malignancies. Although these mutations are most commonly associated with myeloid diseases, they also occur in malignancies of the T-cell lineage. To investigate their role in these diseases and provide tractable disease models for further investigation, we analyzed the T-cell compartment in a conditional knock-in (KI) mouse model of mutant Idh1. We observed the development of a spontaneous T-cell acute lymphoblastic leukemia (T-ALL) in these animals. The disease was transplantable and maintained expression of mutant IDH1. Whole-exome sequencing revealed the presence of a spontaneous activating mutation in Notch1, one of the most common mutations in human T-ALL, suggesting Idh1 mutations may have the capacity to cooperate with Notch1 to drive T-ALL. To further investigate the Idh1 mutation as an oncogenic driver in the T-cell lineage, we crossed Idh1-KI mice with conditional Trp53 null mice, a well-characterized model of T-cell malignancy, and found that T-cell lymphomagenesis was accelerated in mice bearing both mutations. Because both IDH1 and p53 are known to affect cellular metabolism, we compared the requirements for glucose and glutamine in cells derived from these tumors and found that cells bearing the Idh1 mutation have an increased dependence on both glucose and glutamine. These data suggest that mutant IDH1 contributes to malignancy in the T-cell lineage and may alter the metabolic profile of malignant T cells. PMID:26787889

  7. lck-Driven Cre Expression Alters T Cell Development in the Thymus and the Frequencies and Functions of Peripheral T Cell Subsets.

    PubMed

    Carow, Berit; Gao, Yu; Coquet, Jonathan; Reilly, Marie; Rottenberg, Martin E

    2016-09-15

    Conditional gene targeting using the bacteriophage-derived Cre recombinase is widely applied for functional gene studies in mice. Mice transgenic for Cre under the control of the lck gene promoter are used to study the role of loxP-targeted genes in T cell development and function. In this article, we show a striking 65% reduction in cellularity, preferential development of γδ versus αβ T cells, and increased expression of IL-7R in the thymus of mice expressing Cre under the proximal lck promoter (lck-cre(+) mice). The transition from CD4/CD8 double-negative to double-positive cells was blocked, and lck-cre(+) double-positive cells were more prone to apoptosis and showed higher levels of Cre expression. Importantly, numbers of naive T cells were reduced in spleens and lymph nodes of lck-cre(+) mice. In contrast, frequencies of γδ T cells, CD44(+)CD62L(-) effector T cells, and Foxp3(+) regulatory T cells were elevated, as was the frequency of IFN-γ-secreting CD4(+) and CD8(+) T cells. A literature survey of 332 articles that used lck-cre(+) mice for deletion of floxed genes indicated that results are statistically influenced by the control used (lck-cre(+) or lck-cre(-)), more frequently resembling the lck-cre(+) phenotype described in this article if lck-cre(-) controls were used. Altogether, care should be taken when interpreting published results and to properly control targeted gene deletions using the lck-cre(+) strain. PMID:27503210

  8. Protecting and rescuing the effectors: roles of differentiation and survival in the control of memory T cell development

    PubMed Central

    Kurtulus, Sema; Tripathi, Pulak; Hildeman, David A.

    2013-01-01

    Vaccines, arguably the single most important intervention in improving human health, have exploited the phenomenon of immunological memory. The elicitation of memory T cells is often an essential part of successful long-lived protective immunity. Our understanding of T cell memory has been greatly aided by the development of TCR Tg mice and MHC tetrameric staining reagents that have allowed the precise tracking of antigen-specific T cell responses. Indeed, following acute infection or immunization, naïve T cells undergo a massive expansion culminating in the generation of a robust effector T cell population. This peak effector response is relatively short-lived and, while most effector T cells die by apoptosis, some remain and develop into memory cells. Although the molecular mechanisms underlying this cell fate decision remain incompletely defined, substantial progress has been made, particularly with regards to CD8+ T cells. For example, the effector CD8+ T cells generated during a response are heterogeneous, consisting of cells with more or less potential to develop into full-fledged memory cells. Development of CD8+ T cell memory is regulated by the transcriptional programs that control the differentiation and survival of effector T cells. While the type of antigenic stimulation and level of inflammation control effector CD8+ T cell differentiation, availability of cytokines and their ability to control expression and function of Bcl-2 family members governs their survival. These distinct differentiation and survival programs may allow for finer therapeutic intervention to control both the quality and quantity of CD8+ T cell memory. Effector to memory transition of CD4+ T cells is less well characterized than CD8+ T cells, emerging details will be discussed. This review will focus on the recent progress made in our understanding of the mechanisms underlying the development of T cell memory with an emphasis on factors controlling survival of effector T cells

  9. Oligoclonality in the human CD8+ T cell repertoire in normal subjects and monozygotic twins: implications for studies of infectious and autoimmune diseases.

    PubMed Central

    Monteiro, J.; Hingorani, R.; Choi, I. H.; Silver, J.; Pergolizzi, R.; Gregersen, P. K.

    1995-01-01

    BACKGROUND: We have previously demonstrated CD8+ T cell clonal dominance using a PCR assay for the CDR3 length of T cell receptors belonging to a limited number of TCRBV segments/families. In this study, we have modified this approach in order to analyze more comprehensively the frequency of oligoclonality in the CD8+ T cell subset in 25 known TCRBV segments/families. In order to assess the relative roles of genes and environment in the shaping of a clonally restricted CD8+ T cell repertoire, we have analyzed clonal dominance in the CD8+ T cell population of monozygotic twins, related siblings, and adoptees. MATERIALS AND METHODS: Oligoclonality was assessed in the CD8+ T cell subsets using a multiplex PCR approach to assay for CDR3 length variation across 25 different TCRBV segments/families. Specific criteria for oligoclonality were established, and confirmed by direct sequence analysis of the PCR products. This assay was used to investigate the CD8+ T cell repertoire of 56 normal subjects, as well as six sets of monozygotic (MZ) twins. RESULTS: Seventy-two percent of normal subjects (n = 56) had evidence of oligoclonality in the CD8+ T cell subset, using well-defined criteria. Although MZ twins frequently displayed CD8+ T cell clonal dominance, the overall pattern of oligoclonality was very diverse within each twin pair. However, we occasionally observed dominant CD8+ T cell clones that were highly similar in sequence in both members of some twin pairs. Not a single example of such similarity was observed in normal controls or siblings. CONCLUSIONS: Oligoclonality of circulating CD8+ T cells is a characteristic feature of the human immune system; both host genetic factors and environment shape the pattern of oligoclonality in this T cell subset. The high frequency of this phenomenon in normal subjects provides a background with which to evaluate CD8+ T cell oligoclonality in the setting of infection or autoimmune disease. Further phenotypic and functional

  10. The Ets-1 transcription factor controls the development and function of natural regulatory T cells.

    PubMed

    Mouly, Enguerran; Chemin, Karine; Nguyen, Hai Vu; Chopin, Martine; Mesnard, Laurent; Leite-de-Moraes, Maria; Burlen-defranoux, Odile; Bandeira, Antonio; Bories, Jean-Christophe

    2010-09-27

    Regulatory T cells (T reg cells) constitute a population of CD4(+) T cells that limits immune responses. The transcription factor Foxp3 is important for determining the development and function of T reg cells; however, the molecular mechanisms that trigger and maintain its expression remain incompletely understood. In this study, we show that mice deficient for the Ets-1 transcription factor (Ets-1(-/-)) developed T cell-mediated splenomegaly and systemic autoimmunity that can be blocked by functional wild-type T reg cells. Spleens of Ets-1(-/-) mice contained mostly activated T cells, including Th2-polarized CD4(+) cells and had reduced percentages of T reg cells. Splenic and thymic Ets-1(-/-) T reg cells expressed low levels of Foxp3 and displayed the CD103 marker that characterizes antigen-experienced T reg cells. Thymic development of Ets-1(-/-) T reg cells appeared intrinsically altered as Foxp3-expressing cells differentiate poorly in mixed fetal liver reconstituted chimera and fetal thymic organ culture. Ets-1(-/-) T reg cells showed decreased in vitro suppression activity and did not protect Rag2(-/-) hosts from naive T cell-induced inflammatory bowel disease. Furthermore, in T reg cells, Ets-1 interacted with the Foxp3 intronic enhancer and was required for demethylation of this regulatory sequence. These data demonstrate that Ets-1 is required for the development of natural T reg cells and suggest a role for this transcription factor in the regulation of Foxp3 expression. PMID:20855499

  11. Signals required for programming effector and memory development by CD8+ T cells.

    PubMed

    Mescher, Matthew F; Curtsinger, Julie M; Agarwal, Pujya; Casey, Kerry A; Gerner, Michael; Hammerbeck, Christopher D; Popescu, Flavia; Xiao, Zhengguo

    2006-06-01

    Stimulation of naïve CD8+ T cells with antigen and costimulation results in proliferation and weak clonal expansion, but the cells fail to develop effector functions and are tolerant long term. Initiation of the program leading to the strong expansion and development of effector functions and memory requires a third signal that can be provided by interleukin-12 (IL-12) or interferon-alpha (IFN-alpha). CD4+ T cells condition dendritic cells (DCs) to effectively present antigen to CD8+ T cells, and this conditioning involves, at least in part, CD40-dependent upregulation of the production of these signal 3 cytokines by the DCs. Upon being fully activated, the cytotoxic T lymphocytes develop activation-induced non-responsiveness (AINR), a form of split anergy characterized by an inability to produce IL-2 to support continued expansion. If antigen remains present, IL-2 provided by CD4+ T cells can reverse AINR to allow further expansion of the effector population and conversion to responsive memory cells following antigen clearance. If IL-2 or potentially other proliferative signals are not available, persistent antigen holds cells in the AINR state and prevents the development of a responsive memory population. Thus, in addition to antigen and costimulation, CD8+ T cells require cytokine signals at distinct stages of the response to be programmed for optimal generation of effector and memory populations. PMID:16824119

  12. E protein transcription factors are required for the development of CD4(+) lineage T cells.

    PubMed

    Jones-Mason, Mary Elizabeth; Zhao, Xudong; Kappes, Dietmar; Lasorella, Anna; Iavarone, Antonio; Zhuang, Yuan

    2012-03-23

    The double-positive (DP) to single-positive (SP) transition during T cell development is initiated by downregulation of the E protein transcription factors HEB and E2A. Here, we have demonstrated that in addition to regulating the onset of this transition, HEB and E2A also play a separate role in CD4(+) lineage choice. Deletion of HEB and E2A in DP thymocytes specifically blocked the development of CD4(+) lineage T cells. Furthermore, deletion of the E protein inhibitors Id2 and Id3 allowed CD4(+) T cell development but blocked CD8(+) lineage development. Analysis of the CD4(+) lineage transcriptional regulators ThPOK and Gata3 placed HEB and E2A upstream of CD4(+) lineage specification. These studies identify an important role for E proteins in the activation of CD4(+) lineage differentiation as thymocytes undergo the DP to SP transition. PMID:22425249

  13. CD4 memory T cells develop and acquire functional competence by sequential cognate interactions and stepwise gene regulation.

    PubMed

    Kaji, Tomohiro; Hijikata, Atsushi; Ishige, Akiko; Kitami, Toshimori; Watanabe, Takashi; Ohara, Osamu; Yanaka, Noriyuki; Okada, Mariko; Shimoda, Michiko; Taniguchi, Masaru; Takemori, Toshitada

    2016-06-01

    Memory CD4(+) T cells promote protective humoral immunity; however, how memory T cells acquire this activity remains unclear. This study demonstrates that CD4(+) T cells develop into antigen-specific memory T cells that can promote the terminal differentiation of memory B cells far more effectively than their naive T-cell counterparts. Memory T cell development requires the transcription factor B-cell lymphoma 6 (Bcl6), which is known to direct T-follicular helper (Tfh) cell differentiation. However, unlike Tfh cells, memory T cell development did not require germinal center B cells. Curiously, memory T cells that develop in the absence of cognate B cells cannot promote memory B-cell recall responses and this defect was accompanied by down-regulation of genes associated with homeostasis and activation and up-regulation of genes inhibitory for T-cell responses. Although memory T cells display phenotypic and genetic signatures distinct from Tfh cells, both had in common the expression of a group of genes associated with metabolic pathways. This gene expression profile was not shared to any great extent with naive T cells and was not influenced by the absence of cognate B cells during memory T cell development. These results suggest that memory T cell development is programmed by stepwise expression of gatekeeper genes through serial interactions with different types of antigen-presenting cells, first licensing the memory lineage pathway and subsequently facilitating the functional development of memory T cells. Finally, we identified Gdpd3 as a candidate genetic marker for memory T cells. PMID:26714588

  14. 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.

  15. CD16+ monocytes control T-cell subset development in immune thrombocytopenia

    PubMed Central

    Zhong, Hui; Bao, Weili; Li, Xiaojuan; Miller, Allison; Seery, Caroline; Haq, Naznin; Bussel, James

    2012-01-01

    Immune thrombocytopenia (ITP) results from decreased platelet production and accelerated platelet destruction. Impaired CD4+ regulatory T-cell (Treg) compartment and skewed Th1 and possibly Th17 responses have been described in ITP patients. The trigger for aberrant T-cell polarization remains unknown. Because monocytes have a critical role in development and polarization of T-cell subsets, we explored the contribution of monocyte subsets in control of Treg and Th development in patients with ITP. Unlike circulating classic CD14hiCD16− subpopulation, the CD16+ monocyte subset was expanded in ITP patients with low platelet counts on thrombopoietic agents and positively correlated with T-cell CD4+IFN-γ+ levels, but negatively with circulating CD4+CD25hiFoxp3+ and IL-17+ Th cells. Using a coculture model, we found that CD16+ ITP monocytes promoted the expansion of IFN-γ+CD4+ cells and concomitantly inhibited the proliferation of Tregs and IL-17+ Th cells. Th-1–polarizing cytokine IL-12, secreted after direct contact of patient T-cell and CD16+ monocytes, was responsible for the inhibitory effect on Treg and IL-17+CD4+ cell proliferation. Our findings are consistent with ITP CD16+ monocytes promoting Th1 development, which in turn negatively regulates IL-17 and Treg induction. This underscores the critical role of CD16+ monocytes in the generation of potentially pathogenic Th responses in ITP. PMID:22915651

  16. RET/GFRα 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/GFRα 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

  17. 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

  18. Transcriptional repressors, corepressors and chromatin modifying enzymes in T cell development

    PubMed Central

    Shapiro, Michael J.; Shapiro, Virginia Smith

    2010-01-01

    Gene expression is regulated by the combined action of transcriptional activators and transcriptional repressors. Transcriptional repressors function by recruiting corepressor complexes containing histone-modifying enzymes to specific sites within DNA. Chromatin modifying complexes are subsequently recruited, either directly by transcriptional repressors, or indirectly via corepressor complexes and/or histone modifications, to remodel chromatin into either a transcription-friendly ‘open’ form or an inhibitory ‘closed’ form. Transcriptional repressors, corepressors and chromatin modifying complexes play critical roles throughout T cell development. Here, we highlight those genes that function to repress transcription and that have been shown to be required for T cell development. PMID:21163671

  19. T cell receptor-zeta and granzyme B expression in mononuclear cell infiltrates in normal colon mucosa and colon carcinoma.

    PubMed Central

    Mulder, W M; Bloemena, E; Stukart, M J; Kummer, J A; Wagstaff, J; Scheper, R J

    1997-01-01

    BACKGROUND: Whereas the presence of a lymphoid infiltrate has been associated with a favourable prognosis in colorectal carcinoma, the proliferative and cytotoxic responses of freshly isolated tumour infiltrating lymphocytes are frequently impaired. In mice, tumour induced immune suppression has been associated with a decreased expression of the zeta-chain of the T cell receptor (TCR)-CD3 complex, and loss of mRNA for granzyme B. AIM: To compare the expression of TCR-zeta and granzyme B in lymphocytes infiltrating normal colonic mucosa and Duke's A and D colorectal carcinomas. SPECIMENS: Paraffin wax embedded normal (n = 10) and malignant colonic mucosa (seven Dukes's A, nine Dukes's D). METHOD: Immunohistochemistry. RESULTS: The numbers of TCR-zeta + lymphocytes decreased from normal mucosa to Dukes's D carcinomas. In contrast, granzyme B+ lymphocytes were more frequent in Dukes's A carcinomas than in normal mucosa, but disappeared from advanced stage tumours. Granzyme B expressing cells were mainly CD3- (natural killer/lymphokine activated killer cells) in normal mucosa, but CD3+ in tumours, indicating the presence of activated cytotoxic T lymphocytes. In vitro culture of tumour infiltrating lymphocytes rapidly restored the expression of both molecules. CONCLUSION: The frequency of TCR-zeta + and granzyme B+ lymphocytes is decreased in advanced stage colorectal carcinomas. The restoration of expression during in vitro stimulation suggests the presence of tumour derived suppressive factors in situ. Images PMID:9155587

  20. Rational peptide-based tumour vaccine development and T cell monitoring.

    PubMed

    Scheibenbogen, Carmen; Letsch, Anne; Schmittel, Alexander; Asemissen, Anne-Marie; Thiel, Eckhard; Keilholz, Ulrich

    2003-12-01

    Antigen-specific vaccination is a promising emerging treatment option for cancer patients. Results from early clinical vaccination trials with tumour peptides in patients with metastatic disease have shown tumour regressions in few patients usually with limited disease. Current clinical studies focus on the development of more potent vaccination strategies and on the vaccination of patients with occult or small volume metastatic disease. The novel generation of sensitive T-cell assays allowing direct quantitation and characterisation of specific T cells provide an essential tool for further systematic clinical development of vaccine protocols. There is accumulating evidence from clinical cancer vaccination trials of a relation between the induction of specific T cells and clinical efficacy. PMID:15001161

  1. Bioinformatic Description of Immunotherapy Targets for Pediatric T-Cell Leukemia and the Impact of Normal Gene Sets Used for Comparison

    PubMed Central

    Orentas, Rimas J.; Nordlund, Jessica; He, Jianbin; Sindiri, Sivasish; Mackall, Crystal; Fry, Terry J.; Khan, Javed

    2014-01-01

    Pediatric lymphoid leukemia has the highest cure rate of all pediatric malignancies, yet due to its prevalence, still accounts for the majority of childhood cancer deaths and requires long-term highly toxic therapy. The ability to target B-cell ALL with immunoglobulin-like binders, whether anti-CD22 antibody or anti-CD19 CAR-Ts, has impacted treatment options for some patients. The development of new ways to target B-cell antigens continues at rapid pace. T-cell ALL accounts for up to 20% of childhood leukemia but has yet to see a set of high-value immunotherapeutic targets identified. To find new targets for T-ALL immunotherapy, we employed a bioinformatic comparison to broad normal tissue arrays, hematopoietic stem cells (HSC), and mature lymphocytes, then filtered the results for transcripts encoding plasma membrane proteins. T-ALL bears a core T-cell signature and transcripts encoding TCR/CD3 components and canonical markers of T-cell development predominate, especially when comparison was made to normal tissue or HSC. However, when comparison to mature lymphocytes was also undertaken, we identified two antigens that may drive, or be associated with leukemogenesis; TALLA-1 and hedgehog interacting protein. In addition, TCR subfamilies, CD1, activation and adhesion markers, membrane-organizing molecules, and receptors linked to metabolism and inflammation were also identified. Of these, only CD52, CD37, and CD98 are currently being targeted clinically. This work provides a set of targets to be considered for future development of immunotherapies for T-ALL. PMID:24959420

  2. 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

  3. 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

  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 κ 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 β (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. Orchestration of Invariant Natural Killer T cell development by E and Id proteins

    PubMed Central

    Roy, Sumedha; Zhuang, Yuan

    2015-01-01

    Natural Killer T (NKT) cells are αβ T cells that express a semi-invariant T cell receptor (TCR) along with Natural Killer (NK) cell markers, and have an innate cell-like ability to produce a myriad of cytokines very quickly upon antigen exposure and subsequent activation. These cells are diverted from conventional single positive (SP) T cell fate at the double positive (DP) stage where TCR-mediated recognition of a lipid antigen presented on a CD1d molecule promotes their selection into the NKT lineage. Although many key regulatory molecules have been shown to play important roles in the development of NKT cells, the mechanism of lineage specification and acquisition of effector functions in these cells still remain to be fully addressed. In this review we specifically discuss the role of a family of class I Helix Loop Helix proteins known as E proteins, and of their antagonists Id proteins in NKT cell development. Recent works have shown that these proteins play key roles in iNKT development, from the invariant TCR rearrangement to terminal differentiation and maturation. Elucidating these roles provides an opportunity to uncover the transcriptional network that separates NKT cells from the concurrently developed conventional αβ T cells. PMID:25746046

  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. Proteasome immunosubunits protect against the development of CD8 T-cell-mediated autoimmune diseases

    PubMed Central

    Zaiss, Dietmar M.W.; Bekker, Cornelis P.J.; Gröne, Andrea; Lie, Benedicte A.; Sijts, Alice J.A.M.

    2011-01-01

    Exposure of cells to inflammatory cytokines induces the expression of three proteasome immunosubunits, two of which are encoded in the MHC-II region. The induced subunits replace their constitutive homologues in newly formed, so called immunoproteasomes. Immunosubunit incorporation enhances the proteasome’ proteolytic activity and modifies the proteasome’ cleavage site preferences, which improves the generation of many MHC-I presented peptides and shapes the fine-specificity of pathogen-specific CD8 T cell responses. We here report on a second effect of immunoproteasome formation on CD8 T cell responses. We show that mice deficient for the immunosubunits β5i/LMP7 and β2i/MECL-1 develop early-stage multi-organ autoimmunity following irradiation and BM transplantation. Disease symptoms are caused by CD8 T cells and transferrable into immunosubunit-deficient, RAG1-deficient mice. Moreover, using the human Type 1 Diabetes Genetics Consortium (T1DGC) MHC dataset, we identified two SNPs within the β5i/LMP7-encoding gene sequences, that were in strong linkage disequilibrium (LD), as independent genetic risk factors for T1D development in humans. Strikingly, these SNPs significantly enhanced the risk conferred by HLA haplotypes that were formerly shown to predispose for T1D. These data suggest that inflammation-induced immunosubunit expression in peripheral tissues constitutes a mechanism that prevents the development of CD8 T cell mediated autoimmune diseases. PMID:21804012

  8. Evidence of the extrathymic development of tyrosinase-related protein-2-recognizing CD8+ T cells with low avidity

    PubMed Central

    Harada, Mamoru; Yamada, Hisakata; Tatsugami, Katsunori; Nomoto, Kikuo

    2001-01-01

    The majority of the human tumour-associated antigens characterized to date are derived from non–mutated self-proteins. However, nothing is known about the development of autoreactive and tumour-associated antigen-recognizing T cells. Tyrosinase-related protein (TRP)-2 is a non-mutated melanocyte differentiation antigen and TRP-2-recognizing CD8+ T cells are known to show responses to melanoma both in humans and mice. In addition, TRP-2-reactive T cells with low avidity have been suggested to be readily induced from the spleen cells of naïve mice. On the other hand, recent reports suggest that self antigen-reactive CD8+ T cells can be positively selected in the periphery. In this study, we tested the possibility that TRP-2-reactive CD8+ T cells in naïve mice could develop via the extrathymic pathway. As a consequence, TRP-2-reactive CD8+ T cell precursors in naïve C57BL/6 mice were suggested to express both interleukin-2 (IL-2) receptor β chain (IL-2Rβ) and CD44 molecules, in a manner similar to that of extrathymically developed T cells. Furthermore, IL-2Rβ+ CD44+ CD8+ T cells were detected in the adult thymectomized and bone marrow-reconstituted mice, and functional TRP-2-reactive T cells were generated from their spleen cells. Overall, these results suggest that low avidity CD8+ T cells recognizing TRP-2 can be developed extrathymically. PMID:11576222

  9. Development of interleukin-17-producing Vγ2+ γδ T cells is reduced by ICOS signaling in the thymus

    PubMed Central

    Buus, Terkild Brink; Schmidt, Jonas Damgård; Bonefeld, Charlotte Menné; Geisler, Carsten; Lauritsen, Jens Peter Holst

    2016-01-01

    Co-stimulation is an integral part of T cell signaling involved in almost all facets of T cell biology. While much is known about co-stimulation in differentiation and function of conventional αβ T cells, less is known about how co-stimulation affects the development and programming of γδ T cells. In this study, we have investigated the role of inducible T cell co-stimulator (ICOS) on the development of γδ T cells. We show that ICOS is expressed by a population of immature Vγ2+CD45RBlow γδ T cells predisposed to interleukin-17 (IL-17) production. We found that treatment with ICOS specific antibodies drastically reduces fetal development of IL-17-producing γδ T cells by agonistic actions, and that ICOS deficient mice have a significant increase in the population of IL-17-producing Vγ2+ γδ T cells in the thymus, spleen, lymph nodes and skin and exhibit exacerbated sensitization responses to 2,4-dinitrofluorobenzene. In conclusion, this study demonstrates that development of IL-17-producing Vγ2+ γδ T cells is reduced by ICOS signaling in the thymus. PMID:27235509

  10. Comparative assessment of therapeutic safety of norcantharidin, N-farnesyloxy-norcantharimide, and N-farnesyl-norcantharimide against Jurkat T cells relative to human normal lymphoblast

    PubMed Central

    Chang, Ming-Che; Wu, Jin-Yi; Liao, Hui-Fen; Chen, Yu-Jen; Kuo, Cheng-Deng

    2016-01-01

    Abstract The therapeutic safety of an anticancer drug is one of the most important concerns of the physician treating the cancer patient. Half maximal inhibitory concentration (IC50) and hillslope are usually used to represent the strength and sensitivity of an anticancer drug on cancer cells. The therapeutic safety of the anticancer drug can be assessed by comparing the IC50 and hillslope of anticancer drugs on cancer cells relative to normal cells. Since there are situations where “more anticancer activity” implies “more toxicity,” the safety of an anticancer drug in these situations is hard to evaluate by using IC50 and hillslope alone. In a previous study, the “net effect” index was devised to represent the net therapeutic effects of one anticancer drug relative to the other. However, the therapeutic safety of one specific anticancer drug alone was not defined in the “net effect” index. This study introduced the “safety index (SI)” to quantify the degree of safety of an anticancer drug by using 4-parameter logistic model on cancer cells relative to normal cells. The therapeutic safety of norcantharidin (NCTD), N-farnesyloxy-norcantharimide (NOC15), and N-farnesyl-norcantharimide (NC15) in the treatment of Jurkat T cells relative to human normal lymphoblast was compared using the newly defined SI. We found that the SI of NOC15 and NC15 was significantly higher than that of NCTD, suggesting that both NOC15 and NC15 can damage more cancer cells and less normal cells than NCTD. We conclude that both NOC15 and NC15 are safer anticancer drugs than NCTD in the treatment of Jurkat T cells relative to human normal lymphoblast. The SI can be further applied to the screening, developments, and applications of anticancer drugs in the future. PMID:27495082

  11. Normal human CD4(+) helper T cells express Kv1.1 voltage-gated K(+) channels, and selective Kv1.1 block in T cells induces by itself robust TNFα production and secretion and activation of the NFκB non-canonical pathway.

    PubMed

    Fellerhoff-Losch, Barbara; Korol, Sergiy V; Ganor, Yonatan; Gu, Songhai; Cooper, Itzik; Eilam, Raya; Besser, Michal; Goldfinger, Meidan; Chowers, Yehuda; Wank, Rudolf; Birnir, Bryndis; Levite, Mia

    2016-03-01

    TNFα is a very potent and pleiotropic pro-inflammatory cytokine, essential to the immune system for eradicating cancer and microorganisms, and to the nervous system, for brain development and ongoing function. Yet, excess and/or chronic TNFα secretion causes massive tissue damage in autoimmune, inflammatory and neurological diseases and injuries. Therefore, many patients with autoimmune/inflammatory diseases receive anti-TNFα medications. TNFα is secreted primarily by CD4(+) T cells, macrophages, monocytes, neutrophils and NK cells, mainly after immune stimulation. Yet, the cause for the pathologically high and chronic TNFα secretion is unknown. Can blocking of a particular ion channel in T cells induce by itself TNFα secretion? Such phenomenon was never revealed or even hypothesized. In this interdisciplinary study we discovered that: (1) normal human T cells express Kv1.1 voltage-gated potassium channel mRNA, and the Kv1.1 membrane-anchored protein channel; (2) Kv1.1 is expressed in most CD4(+)CD3(+) helper T cells (mean CD4(+)CD3(+)Kv1.1(+) T cells of 7 healthy subjects: 53.09 ± 22.17 %), but not in CD8(+)CD3(+) cytotoxic T cells (mean CD8(+)CD3(+)Kv1.1(+) T cells: 4.12 ± 3.04 %); (3) electrophysiological whole-cell recordings in normal human T cells revealed Kv currents; (4) Dendrotoxin-K (DTX-K), a highly selective Kv1.1 blocker derived from snake toxin, increases the rate of rise and decay of Kv currents in both resting and activated T cells, without affecting the peak current; (5) DTX-K by itself induces robust TNFα production and secretion by normal human T cells, without elevating IFNγ, IL-4 and IL-10; (6) intact Ca(2+) channels are required for DTX-induced TNFα secretion; (7) selective anti-Kv1.1 antibodies also induce by themselves TNFα secretion; (8) DTX-K activates NFκB in normal human T cells via the unique non-canonical-pathway; (9) injection of Kv1.1-blocked human T cells to SCID mice, causes recruitment of resident mouse cells

  12. CD8+ T Cell-Mediated Immunity during Trypanosoma cruzi Infection: A Path for Vaccine Development?

    PubMed Central

    dos Santos Virgilio, Fernando; Pontes, Camila; Dominguez, Mariana Ribeiro; Ersching, Jonatan; Rodrigues, Mauricio Martins; Vasconcelos, José Ronnie

    2014-01-01

    MHC-restricted CD8+ T cells are important during infection with the intracellular protozoan parasite Trypanosoma cruzi, the causative agent of Chagas disease. Experimental studies performed in the past 25 years have elucidated a number of features related to the immune response mediated by these T cells, which are important for establishing the parasite/host equilibrium leading to chronic infection. CD8+ T cells are specific for highly immunodominant antigens expressed by members of the trans-sialidase family. After infection, their activation is delayed, and the cells display a high proliferative activity associated with high apoptotic rates. Although they participate in parasite control and elimination, they are unable to clear the infection due to their low fitness, allowing the parasite to establish the chronic phase when these cells then play an active role in the induction of heart immunopathology. Vaccination with a number of subunit recombinant vaccines aimed at eliciting specific CD8+ T cells can reverse this path, thereby generating a productive immune response that will lead to the control of infection, reduction of symptoms, and reduction of disease transmission. Due to these attributes, activation of CD8+ T lymphocytes may constitute a path for the development of a veterinarian or human vaccine. PMID:25104879

  13. Dietary Zinc Deficiency in Rodents: Effects on T-Cell Development, Maturation and Phenotypes

    PubMed Central

    Blewett, Heather J.; Taylor, Carla G.

    2012-01-01

    Zinc deficiency is one of the leading risk factors for developing disease and yet we do not have a clear understanding of the mechanisms behind the increased susceptibility to infection. This review will examine the interrelationships among the hypothalamus-pituitary-adrenal stress axis, p56lck, and T-cell maturation in both zinc deficiency and responses during zinc repletion. We will highlight differences between the adult mouse model (wasting malnutrition) and growing rat model (stunting malnutrition) of dietary zinc deficiency and discuss the use of various controls to separate out the effects of zinc deficiency from the associated malnutrition. Elevated serum corticosterone in both zinc deficient and pair-fed rats does not support the hypothesis that zinc deficiency per se leads to corticosterone-induced apoptosis and lymphopenia. In fact, the zinc deficient rat does not have lymphopenia. Thymocytes from zinc deficient mice and rats have elevated levels of p56lck, a signalling protein with a zinc clasp structure, but this does not appear to affect thymocyte maturation. However, post-thymic T-cell maturation appears to be altered based on the lower proportion of splenic late thymic emigrants in zinc deficient rats. Fewer new T-cells in the periphery could adversely affect the T-cell repertoire and contribute to immunodeficiency in zinc deficiency. PMID:22822446

  14. Maternal Milk T Cells Drive Development of Transgenerational Th1 Immunity in Offspring Thymus

    PubMed Central

    Ghosh, Mrinal K.; Nguyen, Virginia; Muller, H. Konrad

    2016-01-01

    Using multiple murine foster-nursing protocols, thereby eliminating placental transfer and allowing a distinction between dam- and pup-derived cells, we show that foster nursing by an immunized dam results in development of CD8+ T cells in nonimmunized foster pups that are specific for Ags against which the foster dam was immunized (Mycobacterium tuberculosis or Candida albicans). We have dubbed this process “maternal educational immunity” to distinguish it from passive cellular immunity. Of the variety of maternal immune cells present in milk, only T cells were detected in pup tissues. Maternal T cells, a substantial percentage of which were CD4+MHC class II+, accumulated in the pup thymus and spleen during the nursing period. Further analysis of maternal cells in the pup thymus showed that a proportion was positive for maternal immunogen-specific MHC class II tetramers. To determine the outcome of Ag presentation in the thymus, the maternal or foster pup origin of immunogen-responding CD8+ cells in foster pup spleens was assessed. Whereas ∼10% were maternally derived in the first few weeks after weaning, all immunogen-responding CD8+ T cells were pup derived by 12 wk of age. Pup-derived immunogen-responsive CD8+ cells persisted until at least 1 y of age. Passive cellular immunity is well accepted and has been demonstrated in the human population. In this study, we show an arguably more important role for transferred immune cells: the direction of offspring T cell development. Harnessing maternal educational immunity through prepregnancy immunization programs has potential for improvement of infant immunity. PMID:27496970

  15. Membrane association of the CD3ε signaling domain is required for optimal T cell development and function1

    PubMed Central

    Bettini, Matthew L.; Guy, Clifford; Dash, Pradyot; Vignali, Kate M.; Hamm, David E.; Dobbins, Jessica; Gagnon, Etienne; Thomas, Paul G.; Wucherpfennig, Kai W.; Vignali, Dario A.A.

    2014-01-01

    The T cell receptor (TCR):CD3 complex transduces signals that are critical for optimal T cell development and adaptive immunity. In resting T cells, the CD3ε cytoplasmic tail associates with the plasma membrane via a proximal basic-rich stretch (BRS). Here we show that mice lacking a functional CD3ε-BRS exhibited substantial reductions in thymic cellularity and limited CD4−CD8− double negative-3 (DN3) to DN4 thymocyte transition, due to enhanced DN4 TCR signaling resulting in increased cell death and TCR downregulation in all subsequent populations. Furthermore, positive, but not negative, T cell selection was affected in mice lacking a functional CD3ε-BRS, which led to limited peripheral T cell function and substantially reduced responsiveness to influenza infection. Collectively, these results indicate membrane association of the CD3ε signaling domain is required for optimal thymocyte development and peripheral T cell function. PMID:24899501

  16. Disregulated expression of the transcription factor ThPOK during T-cell development leads to high incidence of T-cell lymphomas

    PubMed Central

    Lee, Hyung-Ok; He, Xiao; Mookerjee-Basu, Jayati; Zhongping, Dai; Hua, Xiang; Nicolas, Emmanuelle; Sulis, Maria Luisa; Ferrando, Adolfo A.; Testa, Joseph R.; Kappes, Dietmar J.

    2015-01-01

    The transcription factor T-helper-inducing POZ/Krueppel-like factor (ThPOK, encoded by the Zbtb7b gene) plays widespread and critical roles in T-cell development, particularly as the master regulator of CD4 commitment. Here we show that mice expressing a constitutive T-cell–specific ThPOK transgene (ThPOKconst mice) develop thymic lymphomas. These tumors resemble human T-cell acute lymphoblastic leukemia (T-ALL), in that they predominantly exhibit activating Notch1 mutations. Lymphomagenesis is prevented if thymocyte development is arrested at the DN3 stage by recombination-activating gene (RAG) deficiency, but restored by introduction of a T-cell receptor (TCR) transgene or by a single injection of anti-αβTCR antibody into ThPOKconst RAG-deficient mice, which promotes development to the CD4+8+ (DP) stage. Hence, TCR signals and/or traversal of the DN (double negative) > DP (double positive) checkpoint are required for ThPOK-mediated lymphomagenesis. These results demonstrate a novel link between ThPOK, TCR signaling, and lymphomagenesis. Finally, we present evidence that ectopic ThPOK expression gives rise to a preleukemic and self-perpetuating DN4 lymphoma precursor population. Our results collectively define a novel role for ThPOK as an oncogene and precisely map the stage in thymopoiesis susceptible to ThPOK-dependent tumor initiation. PMID:26056302

  17. CCR10 is important for the development of skin-specific γδT cells by regulating their migration and location

    PubMed Central

    Jin, Yan; Xia, Mingcan; Sun, Allen; Saylor, Christina M.; Xiong, Na

    2011-01-01

    Unlike conventional αβ T cells, which preferentially reside in secondary lymphoid organs for adaptive immune responses, various subsets of un-conventional T cells, such as the γδ T cells with innate properties, preferentially reside in epithelial tissues as the first line of defence. However, mechanisms underlying their tissue-specific development are not well understood. We herein report that among different thymic T cell subsets fetal thymic precursors of the prototypic skin intraepithelial Vγ3+ T lymphocytes (sIEL) were selected to display a unique pattern of homing molecules, including a high level of CCR10 expression that was important for their development into sIELs. In fetal CCR10 knockout mice, the Vγ3+ sIEL precursors developed normally in the thymus, but were defective in migrating into the skin. While the earlier defect in the skin-seeding by sIEL precursors was partially compensated for by their normal expansion in the skin of adult CCR10 knockout mice, the Vγ3+ sIELs displayed the abnormal morphology and increasingly accumulated in the dermal region of skin. These findings provide the definite evidence that CCR10 is important in the sIEL development by regulating the migration of sIEL precursors and their maintenance in proper regions of the skin and support the notion that unique homing properties of different thymic T cell subsets plays an important role in their peripheral location. PMID:20937851

  18. 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

  19. Heterogeneous MHC II restriction pattern of autoreactive desmoglein 3 specific T cell responses in pemphigus vulgaris patients and normals.

    PubMed

    Hertl, M; Karr, R W; Amagai, M; Katz, S I

    1998-04-01

    Pemphigus vulgaris is a life threatening bullous autoimmune disease of the skin mediated by autoantibodies against desmoglein 3 (Dsg3) on epidermal keratinocytes. Pemphigus vulgaris patients exhibit T cell responses against Dsg3 that may serve as a target to modulate the production of pathogenic autoantibodies. Healthy carriers of major histocompatibility complex class II alleles identical or similar to those that are highly prevalent in pemphigus vulgaris, namely DRbeta1*0402 and DRbeta1*1401, also mount T cell responses against Dsg3. We thus wanted to determine whether these prevalent major histocompatibility complex class II alleles restricted Dsg3 specific T cell responses. A CD4+ T cell line from the DRbeta1*0402+ patient PV9 was stimulated by Dsg3 with DRbeta1*0402+ L cells as antigen-presenting cells. A CD4+ T cell line and six CD4+ T cell clones from the DR11/14+ patient PV8, and six CD4+ T cell clones from the DR11+ healthy donor C6, required DR11/ DQbeta1*0301+ peripheral blood mononuclear cells but not DR11+ L cells as antigen-presenting cells and were strongly inhibited by anti-DQ antibodies, indicating that they were restricted by HLA-DQbeta1*0301. A CD4+ T cell line and three T cell clones from the DR11+ healthy donor C11 were differentially stimulated by Dsg3 with L cells expressing one of several DR11 alleles. T cell recognition of Dsg3 was thus not only restricted by the pemphigus vulgaris associated DRbeta1*0402 allele, but also by several DR11 alleles, some of which are highly homologous to DRbeta1*0402, and by HLA-DQbeta1*0301. PMID:9540980

  20. Molecular Determinants of Regulatory T Cell Development: The Essential Roles of Epigenetic Changes

    PubMed Central

    Kitagawa, Yohko; Ohkura, Naganari; Sakaguchi, Shimon

    2013-01-01

    Regulatory T (Treg) cells constitute a distinct T cell subset, which plays a key role in immune tolerance and homeostasis. The transcription factor Foxp3 controls a substantial part of Treg cell development and function. Yet its expression alone is insufficient for conferring developmental and functional characteristics of Treg cells. There is accumulating evidence that concurrent induction of Treg-specific epigenetic changes and Foxp3 expression is crucial for lineage specification and functional stability of Treg cells. This review discusses recent progress in our understanding of molecular features of Treg cells, in particular, the molecular basis of how a population of developing T cells is driven to the Treg cell lineage and how its function is stably maintained. PMID:23675373

  1. Mtg16/Eto2 contributes to murine T-cell development.

    PubMed

    Hunt, Aubrey; Fischer, Melissa; Engel, Michael E; Hiebert, Scott W

    2011-07-01

    Mtg16/Eto2 is a transcriptional corepressor that is disrupted by t(16;21) in acute myeloid leukemia. Using mice lacking Mtg16, we found that Mtg16 is a critical regulator of T-cell development. Deletion of Mtg16 led to reduced thymocyte development in vivo, and after competitive bone marrow transplantation, there was a nearly complete failure of Mtg16(-/-) cells to contribute to thymocyte development. This defect was recapitulated in vitro as Mtg16(-/-) Lineage(-)/Sca1(+)/c-Kit(+) (LSK) cells of the bone marrow or DN1 cells of the thymus failed to produce CD4(+)/CD8(+) cells in response to a Notch signal. Complementation of these defects by reexpressing Mtg16 showed that 3 highly conserved domains were somewhat dispensable for T-cell development but required the capacity of Mtg16 to suppress E2A-dependent transcriptional activation and to bind to the Notch intracellular domain. Thus, Mtg16 integrates the activities of signaling pathways and nuclear factors in the establishment of T-cell fate specification. PMID:21536648

  2. TCR Affinity for Self-Ligands Influences the Development and Function of Encephalitogenic T Cells

    PubMed Central

    Sant'Angelo, Derek B.

    2011-01-01

    The specificity and affinity of self-reactive T cells is likely to impact the development of autoimmune-disease causing T cells in the thymus as well as their function in the periphery. We identified a naturally occurring, low affinity variant of an MBP Ac1-11/I-Au specific TCR that is known to induce EAE. Thymocytes in mice carrying the transgenes for this low affinity TCR were poorly positively selected, as compared to their high affinity TCR expressing counterparts. Nonetheless, CD4 T cells bearing the low affinity TCR accumulated in the periphery of the mice. Unlike mice expressing the high affinity TCR, these mice very rarely developed disease. However, if endogenous TCR expression was eliminated by breeding to RAG1 deficient mice, 100% of the mice carrying either the high or the low affinity versions of the TCR developed EAE. Intriguingly, while the incidence of EAE increased, the age of onset of disease in both mice was identical. These data suggest disease onset occurs during a short window of mouse development. PMID:21437282

  3. STAT3 Impairs STAT5 Activation in the Development of IL-9-Secreting T Cells.

    PubMed

    Olson, Matthew R; Verdan, Felipe Fortino; Hufford, Matthew M; Dent, Alexander L; Kaplan, Mark H

    2016-04-15

    Th cell subsets develop in response to multiple activating signals, including the cytokine environment. IL-9-secreting T cells develop in response to the combination of IL-4 and TGF-β, although they clearly require other cytokine signals, leading to the activation of transcription factors including STAT5. In Th17 cells, there is a molecular antagonism of STAT5 with STAT3 signaling, although whether this paradigm exists in other Th subsets is not clear. In this paper, we demonstrate that STAT3 attenuates the ability of STAT5 to promote the development of IL-9-secreting T cells. We demonstrate that production of IL-9 is increased in the absence of STAT3 and cytokines that result in a sustained activation of STAT3, including IL-6, have the greatest potency in repressing IL-9 production in a STAT3-dependent manner. Increased IL-9 production in the absence of STAT3 correlates with increased endogenous IL-2 production and STAT5 activation, and blocking IL-2 responses eliminates the difference in IL-9 production between wild-type and STAT3-deficient T cells. Moreover, transduction of developing Th9 cells with a constitutively active STAT5 eliminates the ability of IL-6 to reduce IL-9 production. Thus, STAT3 functions as a negative regulator of IL-9 production through attenuation of STAT5 activation and function. PMID:26976954

  4. Hormonal control of T-cell development in health and disease.

    PubMed

    Savino, Wilson; Mendes-da-Cruz, Daniella Arêas; Lepletier, Ailin; Dardenne, Mireille

    2016-02-01

    The physiology of the thymus, the primary lymphoid organ in which T cells are generated, is controlled by hormones. Data from animal models indicate that several peptide and nonpeptide hormones act pleiotropically within the thymus to modulate the proliferation, differentiation, migration and death by apoptosis of developing thymocytes. For example, growth hormone and prolactin can enhance thymocyte proliferation and migration, whereas glucocorticoids lead to the apoptosis of these developing cells. The thymus undergoes progressive age-dependent atrophy with a loss of cells being generated and exported, therefore, hormone-based therapies are being developed as an alternative strategy to rejuvenate the organ, as well as to augment thymocyte proliferation and the export of mature T cells to peripheral lymphoid organs. Some hormones (such as growth hormone and progonadoliberin-1) are also being used as therapeutic agents to treat immunodeficiency disorders associated with thymic atrophy, such as HIV infection. In this Review, we discuss the accumulating data that shows the thymus gland is under complex and multifaceted hormonal control that affects the process of T-cell development in health and disease. PMID:26437623

  5. 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

  6. The chromatin remodeler Mi-2beta is required for CD4 expression and T cell development.

    PubMed

    Williams, Christine J; Naito, Taku; Arco, Pablo Gómez-Del; Seavitt, John R; Cashman, Susan M; De Souza, Beverly; Qi, Xiaoqing; Keables, Piper; Von Andrian, Ulrich H; Georgopoulos, Katia

    2004-06-01

    Changes in chromatin structure underlie the activation or silencing of genes during development. The chromatin remodeler Mi-2beta is highly expressed in thymocytes and is presumed to be a transcriptional repressor because of its presence in the nucleosome remodeling deacetylase (NuRD) complex. Using conditional inactivation, we show that Mi-2beta is required at several steps during T cell development: for differentiation of beta selected immature thymocytes, for developmental expression of CD4, and for cell divisions in mature T cells. We further show that Mi-2beta plays a direct role in promoting CD4 gene expression. Mi-2beta associates with the CD4 enhancer as well as the E box binding protein HEB and the histone acetyltransferase (HAT) p300, enabling their recruitment to the CD4 enhancer and causing histone H3-hyperacetylation to this regulatory region. These findings provide important insights into the regulation of CD4 expression during T cell development and define a role for Mi-2beta in gene activation. PMID:15189737

  7. 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 αβ 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

  8. 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

  9. 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-κB 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

  10. 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-κB 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

  11. Generation of Functional Thymic Epithelium from Human Embryonic Stem Cells that Supports Host T Cell Development

    PubMed Central

    Parent, Audrey V.; Russ, Holger A.; Khan, Imran S.; LaFlam, Taylor N.; Metzger, Todd C.; Anderson, Mark S.; Hebrok, Matthias

    2013-01-01

    SUMMARY Inducing immune tolerance to prevent rejection is a key step toward successful engraftment of stem-cell-derived tissue in a clinical setting. Using human pluripotent stem cells to generate thymic epithelial cells (TECs) capable of supporting T cell development represents a promising approach to reach this goal; however, progress toward generating functional TECs has been limited. Here, we describe a robust in vitro method to direct differentiation of human embryonic stem cells (hESCs) into thymic epithelial progenitors (TEPs) by precise regulation of TGFβ, BMP4, RA, Wnt, Shh, and FGF signaling. The hESC-derived TEPs further mature into functional TECs that support T cell development upon transplantation into thymus-deficient mice. Importantly, the engrafted TEPs produce T cells capable of in vitro proliferation as well as in vivo immune responses. Thus, hESC-derived TEP grafts may have broad applications for enhancing engraftment in cell-based therapies as well as restoring age-and stress-related thymic decline. PMID:23684540

  12. CXCR3 Blockade Inhibits T Cell Migration into the Skin and Prevents Development of Alopecia Areata.

    PubMed

    Dai, Zhenpeng; Xing, Luzhou; Cerise, Jane; Wang, Eddy Hsi Chun; Jabbari, Ali; de Jong, Annemieke; Petukhova, Lynn; Christiano, Angela M; Clynes, Raphael

    2016-08-15

    Alopecia areata (AA) is an autoimmune disease of the hair follicle that results in hair loss of varying severity. Recently, we showed that IFN-γ-producing NKG2D(+)CD8(+) T cells actively infiltrate the hair follicle and are responsible for its destruction in C3H/HeJ AA mice. Our transcriptional profiling of human and mouse alopecic skin showed that the IFN pathway is the dominant signaling pathway involved in AA. We showed that IFN-inducible chemokines (CXCL9/10/11) are markedly upregulated in the skin of AA lesions, and further, that the IFN-inducible chemokine receptor, CXCR3, is upregulated on alopecic effector T cells. To demonstrate whether CXCL9/10/11 chemokines were required for development of AA, we treated mice with blocking Abs to CXCR3, which prevented the development of AA in the graft model, inhibiting the accumulation of NKG2D(+)CD8(+) T cells in the skin and cutaneous lymph nodes. These data demonstrate proof of concept that interfering with the Tc1 response in AA via blockade of IFN-inducible chemokines can prevent the onset of AA. CXCR3 blockade could be approached clinically in human AA with either biologic or small-molecule inhibition, the latter being particularly intriguing as a topical therapeutic. PMID:27412416

  13. 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.

  14. MicroRNA-155 promotes autoimmune inflammation by enhancing inflammatory T cell development.

    PubMed

    O'Connell, Ryan M; Kahn, Daniel; Gibson, William S J; Round, June L; Scholz, Rebecca L; Chaudhuri, Aadel A; Kahn, Melissa E; Rao, Dinesh S; Baltimore, David

    2010-10-29

    Mammalian noncoding microRNAs (miRNAs) are a class of gene regulators that have been linked to immune system function. Here, we have investigated the role of miR-155 during an autoimmune inflammatory disease. Consistent with a positive role for miR-155 in mediating inflammatory responses, Mir155(-/-) mice were highly resistant to experimental autoimmune encephalomyelitis (EAE). miR-155 functions in the hematopoietic compartment to promote the development of inflammatory T cells including the T helper 17 (Th17) cell and Th1 cell subsets. Furthermore, the major contribution of miR-155 to EAE was CD4(+) T cell intrinsic, whereas miR-155 was also required for optimum dendritic cell production of cytokines that promoted Th17 cell formation. Our study shows that one aspect of miR-155 function is the promotion of T cell-dependent tissue inflammation, suggesting that miR-155 might be a promising therapeutic target for the treatment of autoimmune disorders. PMID:20888269

  15. Design and Development of Therapies using Chimeric Antigen Receptor-Expressing T cells

    PubMed Central

    Dotti, Gianpietro; Gottschalk, Stephen; Savoldo, Barbara; Brenner, Malcolm K

    2013-01-01

    Summary Investigators developed chimeric antigen receptors (CARs) for expression on T cells more than 25 years ago. When the CAR is derived from an antibody, the resultant cell should combine the desirable targeting features of an antibody (e.g. lack of requirement for major histocompatibility complex recognition, ability to recognize non-protein antigens) with the persistence, trafficking and effector functions of a T-cell. This article describes how the past two decades have seen a crescendo of research which has now begun to translate these potential benefits into effective treatments for patients with cancer. We describe the basic design of CARs, describe how antigenic targets are selected, and the initial clinical experience with CART cells. Our review then describes our own and other investigators’ work aimed at improving the function of CARs and reviews the clinical studies in hematological and solid malignancies that are beginning to exploit these approaches. Finally, we show the value of adding additional engineering features to CAR-T cells, irrespective of their target, to render them better suited to function in the tumor environment, and discuss how the safety of these heavily modified cells may be maintained. PMID:24329793

  16. Clonal deletion of self-reactive T cells at the early stage of T cell development in thymus of radiation bone marrow chimeras

    SciTech Connect

    Matsuzaki, G.; Yoshikai, Y.; Ogimoto, M.; Kishihara, K.; Nomoto, K. )

    1990-07-01

    Sequential appearance of T cell subpopulations occurs in the thymocytes of irradiated C3H/He mice (H-2k, Mls-1b2a, Thy-1.2) after transplantation with bone marrow cells of AKR/J mice (H-2k, Mls-1a2b, Thy-1.1) (AKR----C3H chimeras). The donor-derived thymocytes of AKR----C3H chimeras on day 14 after bone marrow transplantation (BMT) contained a large number of blastlike CD4+CD8+ cells which represent relatively immature thymocytes, whereas those on day 21 after BMT consisted of small sized CD4+,CD8+ cells which represent a great part in normal thymocytes. To define the developmental stage at which clonal deletion of self-reactive T cells occurs in adult thymus, we followed the fate of V beta 6- or V beta 11-bearing T cells in the donor-derived thymocytes at the early stage of AKR----C3H chimeras. Mature thymocytes expressing high intensity of V beta 6 or V beta 11, which are involved in recognition of Mls-1a or MHC I-E gene products, respectively, were deleted from the donor-derived thymocytes on day 21. Immature thymocytes expressing low intensity of V beta 6 in CD3low thymocyte fraction decreased in proportion, whereas those expressing low intensity of V beta 11 rather increased in proportion in the donor-derived thymocytes of AKR----C3H chimeras from day 14 to day 21 after BMT. These results suggest that the clonal deletion of V beta 6-positive cells occurs just at the stage of immature CD3lowCD4+CD8+ cells, whereas the clonal deletion of V beta 11-positive cells may begin at the transitional stage from CD3lowCD4+CD8+ cells to CD3high single positive cells. Timing of negative selection of thymocytes may vary in distinct T cells capable of recognizing different self-Ag.

  17. Transient CD4+ T Cell Depletion Results in Delayed Development of Functional Vaccine-Elicited Antibody Responses

    PubMed Central

    Provine, Nicholas M.; Badamchi-Zadeh, Alexander; Bricault, Christine A.; Penaloza-MacMaster, Pablo; Larocca, Rafael A.; Borducchi, Erica N.; Seaman, Michael S.

    2016-01-01

    ABSTRACT We have recently demonstrated that CD4+ T cell help is required at the time of adenovirus (Ad) vector immunization for the development of functional CD8+ T cell responses, but the temporal requirement for CD4+ T cell help for the induction of antibody responses remains unclear. Here we demonstrate that induction of antibody responses in C57BL/6 mice can occur at a time displaced from the time of Ad vector immunization by depletion of CD4+ T cells. Transient depletion of CD4+ T cells at the time of immunization delays the development of antigen-specific antibody responses but does not permanently impair their development or induce tolerance against the transgene. Upon CD4+ T cell recovery, transgene-specific serum IgG antibody titers develop and reach a concentration equivalent to that in undepleted control animals. These delayed antibody responses exhibit no functional defects with regard to isotype, functional avidity, expansion after boosting immunization, or the capacity to neutralize a simian immunodeficiency virus (SIV) Env-expressing pseudovirus. The development of this delayed transgene-specific antibody response is temporally linked to the expansion of de novo antigen-specific CD4+ T cell responses, which develop after transient depletion of CD4+ T cells. These data demonstrate that functional vaccine-elicited antibody responses can be induced even if CD4+ T cell help is provided at a time markedly separated from the time of vaccination. IMPORTANCE CD4+ T cells have a critical role in providing positive help signals to B cells, which promote robust antibody responses. The paradigm is that helper signals must be provided immediately upon antigen exposure, and their absence results in tolerance against the antigen. Here we demonstrate that, in contrast to the current model that the absence of CD4+ T cell help at priming results in long-term antibody nonresponsiveness, antibody responses can be induced by adenovirus vector immunization or alum

  18. β-catenin/TCF-1 pathway in T cell development and differentiation

    PubMed Central

    Ma, Jian; Wang, Ruiqing; Fang, Xianfeng; Sun, Zuoming

    2013-01-01

    T cells must undergo two critical differentiation processes before they become competent effectors that can mediate actual immune responses. Progenitor T cells undergo defined stages of differentiation in the thymus, which include positive and negative selection, to generate a repertoire of T cells that will respond to foreign but not self antigens. When these immunocompetent T cells first migrate out of thymus into peripheral lymphoid tissues, they are naïve and are unable to mediate immune responses. However, upon antigen encounter, peripheral CD4+ naïve T cells undergo another differentiation process to become armed effector T cells including Th1, Th2, Th17 or regulatory T cells, all of which are capable of regulating immune responses. A canonical Wnt/β-catenin/T cell factor (TCF) pathway has been shown to regulate T cell differentiation in both the thymus and in peripheral lymphoid tissues. Dysfunction of this pathway at any stage of T cell differentiation could lead to severe autoimmunity including experimental autoimmune encephalomyelitis or immune deficiency. Understanding the role played by β-catenin/TCF-1 in T cell differentiation will facilitate our understanding of the mechanisms that regulate T cell function and assist in identifying novel therapy targets for treating both autoimmune and immune diseases. Therefore, in this review, we will focus on the function of β-catenin/TCF-1 pathway in the regulation of thymic and peripheral T cell differentiation processes. PMID:22535304

  19. Development of lifitegrast: a novel T-cell inhibitor for the treatment of dry eye disease

    PubMed Central

    Semba, Charles P; Gadek, Thomas R

    2016-01-01

    Dry eye disease (DED) is a multifactorial disorder of the ocular surface characterized by symptoms of discomfort, decreased tear quality, and chronic inflammation that affects an estimated 20 million patients in the US alone. DED is associated with localized inflammation of the ocular surface and periocular tissues leading to homing and activation of T cells, cytokine release, and development of hyperosmolar tears. This inflammatory milieu results in symptoms of eye dryness and discomfort. Homing of T cells to the ocular surface is influenced by the binding of lymphocyte function-associated antigen-1 (LFA-1; CD11a/CD18; αLβ2), a cell surface adhesion protein, to its cognate ligand, intercellular adhesion molecule-1 (ICAM-1; CD54), which is expressed on inflamed ocular/periocular epithelium and vascular endothelium. LFA-1/ICAM-1 binding within the immunologic synapse enables both T-cell activation and cytokine release. Lifitegrast is a novel T-cell integrin antagonist that is designed to mimic the binding epitope of ICAM-1. It serves as a molecular decoy to block the binding of LFA-1/ICAM-1 and inhibits the downstream inflammatory process. In vitro studies have demonstrated that lifitegrast inhibits T-cell adhesion to ICAM-1-expressing cells and inhibits secretion of pro-inflammatory cytokines including interferon gamma, tumor necrosis factor alpha, macrophage inflammatory protein 1 alpha, interleukin (IL)-1α, IL-1β, IL-2, IL-4, and IL-6, all of which are known to be associated with DED. Lifitegrast has the potential to be the first pharmaceutical product approved in the US indicated for the treatment of both symptoms and signs of DED. Clinical trials involving over 2,500 adult DED patients have demonstrated that topically administered lifitegrast 5.0% ophthalmic solution can rapidly reduce the symptoms of eye dryness and decrease ocular surface staining with an acceptable long-term safety profile. The purpose of this review is to highlight the developmental

  20. Comparative contribution of CD1 on the development of CD4+ and CD8+ T cell compartments.

    PubMed

    Wang, B; Chun, T; Wang, C R

    2000-01-15

    CD1 molecules are MHC class I-like glycoproteins whose expression is essential for the development of a unique subset of T cells, the NK T cells. To evaluate to what extent CD1 contributes to the development of CD4+ and CD8+ T cells, we generated CD1oIIo and CD1oTAPo mice and compared the generation of T cells in these double-mutant mice and IIo or TAPo mice. FACS analysis showed that the number of CD4+ T cells in CD1oIIo mice was reduced significantly compared with the corresponding population in IIo mice. Both CD4+ NK1.1+ and the CD4+ NK1.1- population were reduced in CD1oIIo mice, suggesting that CD1 can select not only CD4+ NK1.1+ T cells but also some NK1.1- CD4+ T cells. Functional analysis showed that the residual CD4+ cells in CD1oIIo can secrete large amounts of IFN-gamma and a significant amount of IL-4 during primary stimulation with anti-CD3, suggesting that this population may be enriched for NK T cells restricted by other class I molecules. In contrast to the CD4+ population, no significant differences in the CD8+ T cell compartment can be detected between TAPo and CD1oTAPo mice in all lymphoid tissues tested, including intestinal intraepithelial lymphocytes. Our data suggest that, unlike other MHC class I molecules, CD1 does not contribute in a major way to the development of CD8+ T cells. PMID:10623818

  1. De novo alloreactive memory CD8+ T cells develop following allogeneic challenge when CNI immunosuppression is delayed.

    PubMed

    Hart-Matyas, M; Gareau, A J; Hirsch, G M; Lee, T D G

    2015-01-01

    Allospecific memory T cells are a recognized threat to the maintenance of solid-organ transplants. Limited information exists regarding the development of alloreactive memory T cells when post-transplant immunosuppression is present. The clinical practice of delaying calcineurin inhibitor (CNI) initiation post-transplant may permit the development of a de novo allospecific memory population. We investigated the development of de novo allospecific memory CD8+ T cells following the introduction of CNI immunosuppression in a murine model using allogeneic cell priming. Recipient mice alloprimed with splenocytes from fully mismatched donors received cyclosporine (CyA), initiated at 0, 2, 6, or 10days post-prime. Splenocytes from recipients were analyzed by flow cytometry or enzyme-linked immunosorbent assay for evidence of memory cell formation. Memory and effector CD8+ T cell development was prevented when CyA was initiated at 0day or 2days post-prime (p<0.001), but not 6days post-prime. Following a boost challenge, these memory CD8+ T cells were capable of producing a similarly sized population of secondary effectors as recipients not treated with CyA (p>0.05). Delaying CyA up to 6days or later post-prime permits the development of functional de novo allospecific memory CD8+ T cells. The development of this potentially detrimental T cell population in patients could be prevented by starting CNI immunosuppression early post-transplant. PMID:25315500

  2. Normal Psychosexual Development

    ERIC Educational Resources Information Center

    Rutter, Michael

    1971-01-01

    Normal sexual development is reviewed with respect to physical maturation, sexual interests, sex drive", psychosexual competence and maturity, gender role, object choice, children's concepts of sexual differences, sex role preference and standards, and psychosexual stages. Biologic, psychoanalytic and psychosocial theories are briefly considered.…

  3. T cell receptor usage in rheumatic disease.

    PubMed

    Richardson, B C

    1992-01-01

    Protection against microbial attack or invasion is a fundamental function of the immune system. Crucial to this function is the ability to distinguish "self" from the invading organism, and tolerate "self" while removing "non-self". The ability to distinguish self from non-self is not inherent in the immune system, but rather is acquired and continuously maintained. Unfortunately, the mechanisms maintaining self-tolerance are not perfect, and at times break down. In these instances an autoimmune disease results. T cells initiate normal immune responses, and it is now clear that T cells can also initiate pathologic immune responses. In animal models, T cells produce diseases resembling rheumatoid arthritis (RA) (1-3), systemic lupus erythematosus (4-6) and progressive systemic sclerosis (7,8). It is likely that T cells participate in human autoimmune diseases as well. The molecular basis of T cell antigen recognition has been clarified over the past decade. These advances now allow direct examination of the T cell receptor (TCR) molecules participating in autoimmune responses, and raise the exciting possibility that the cells inducing autoimmune responses may finally be identified. Selective agents might then be developed which would interfere with or inhibit the cells. Understanding these developments requires detailed knowledge of how T cells recognize antigen, and of the receptors involved in autoimmune diseases. This article reviews the current literature on T cell receptor structure, and summarizes what is currently known about the usage of specific T cell receptors in autoimmune rheumatic disease. PMID:1582073

  4. Stem cell-derived tissue-associated regulatory T cells ameliorate the development of autoimmunity

    PubMed Central

    Haque, Mohammad; Song, Jianyong; Fino, Kristin; Sandhu, Praneet; Song, Xinmeng; Lei, Fengyang; Zheng, Songguo; Ni, Bing; Fang, Deyu; Song, Jianxun

    2016-01-01

    Pluripotent stem cells (PSCs) have the potential to produce almost all of the cells in the body, including regulatory T cells (Tregs). However, the exact conditions required for the development of antigen (Ag)-specific Tregs from PSCs (i.e., PSC-Tregs) are not well delineated. Ag-specific PSC-Tregs can be tissue/organ-associated and migrate to local inflamed tissues/organs to suppress the autoimmune response after adoptive transfer, thereby avoiding potential overall immunosuppression from non-specific Tregs. In this study, we developed a new approach to generate functional Ag-specific Tregs from induced PSCs (iPSCs), i.e., iPSC-Tregs, which had the ability to generate an Ag-specific immunosuppressive response in a murine model of arthritis. We retrovirally transduced murine iPSCs with a construct containing genes of Ag-specific T cell receptor (TCR) and the transcriptional factor FoxP3. We differentiated the iPSCs into Ag-specific iPSC-Tregs using in vitro or in vivo Notch signaling, and demonstrated that adoptive transfer of such Tregs dramatically suppressed autoimmunity in a well-established Ag-induced arthritis model, including the inflammation, joint destruction, cartilage prostaglandin depletion, osteoclast activity, and Th17 production. Our results indicate that PSCs can be used to develop Ag-specific Tregs, which have a therapeutic potential for Treg-based therapies of autoimmune disorders. PMID:26846186

  5. Impaired memory CD8 T cell development in the absence of methyl-CpG-binding domain protein 2.

    PubMed

    Kersh, Ellen N

    2006-09-15

    Intracellular differentiation events that determine which cells develop into memory CD8 T cells are currently incompletely understood. Methyl-CpG-binding domain protein 2 (MBD2) is a transcriptional repressor that binds to methylated DNA and mediates the biological consequences of epigenetic gene methylation. The role of MBD2 during the differentiation of naive CD8 T cells into effector and memory cells was determined following acute infection of MBD2-deficient mice with lymphocytic choriomeningitis virus. Despite rapid viral clearance and an efficient primary effector CD8 T cell response, reduced numbers of Ag-specific memory CD8 T cells were observed. Importantly, the appearance of precursor memory cells (IL-7Ralphahigh) was delayed. The remaining MBD2(-/-) memory cells were not fully protective during rechallenge, and memory cell characteristics were altered with regard to surface markers (IL-7Ralpha, KLRG-1, CD27, and others) and cytokine production. The defect was CD8 T cell intrinsic, because memory cell development was also delayed when MBD2(-/-) CD8 T cells were adoptively transferred into SCID mice. These data demonstrate that MBD2 is a previously unrecognized intracellular factor required for the efficient generation of protective memory CD8 T cells. PMID:16951344

  6. Agonistic Anti-TIGIT Treatment Inhibits T Cell Responses in LDLr Deficient Mice without Affecting Atherosclerotic Lesion Development

    PubMed Central

    Foks, Amanda C.; Ran, Ingrid A.; Frodermann, Vanessa; Bot, Ilze; van Santbrink, Peter J.; Kuiper, Johan; van Puijvelde, Gijs H. M.

    2013-01-01

    Objective Co-stimulatory and co-inhibitory molecules are mainly expressed on T cells and antigen presenting cells and strongly orchestrate adaptive immune responses. Whereas co-stimulatory molecules enhance immune responses, signaling via co-inhibitory molecules dampens the immune system, thereby showing great therapeutic potential to prevent cardiovascular diseases. Signaling via co-inhibitory T cell immunoglobulin and ITIM domain (TIGIT) directly inhibits T cell activation and proliferation, and therefore represents a novel therapeutic candidate to specifically dampen pro-atherogenic T cell reactivity. In the present study, we used an agonistic anti-TIGIT antibody to determine the effect of excessive TIGIT-signaling on atherosclerosis. Methods and Results TIGIT was upregulated on CD4+ T cells isolated from mice fed a Western-type diet in comparison with mice fed a chow diet. Agonistic anti-TIGIT suppressed T cell activation and proliferation both in vitro and in vivo. However, agonistic anti-TIGIT treatment of LDLr−/− mice fed a Western-type diet for 4 or 8 weeks did not affect atherosclerotic lesion development in comparison with PBS and Armenian Hamster IgG treatment. Furthermore, elevated percentages of dendritic cells were observed in the blood and spleen of agonistic anti-TIGIT-treated mice. Additionally, these cells showed an increased activation status but decreased IL-10 production. Conclusions Despite the inhibition of splenic T cell responses, agonistic anti-TIGIT treatment does not affect initial atherosclerosis development, possibly due to increased activity of dendritic cells. PMID:24376654

  7. A Genome-wide Regulatory Network Identifies Key Transcription Factors for Memory CD8+ T Cell Development

    PubMed Central

    Hu, Guangan; Chen, Jianzhu

    2014-01-01

    Memory CD8+ T cell development is defined by the expression of a specific set of memory signature genes (MSGs). Despite recent progress, many components of the transcriptional control of memory CD8+ T cell development are still unknown. To identify transcription factors (TFs) and their interactions in memory CD8+ T cell development, we construct a genome-wide regulatory network and apply it to identify key TFs that regulate MSGs. Most of the known TFs in memory CD8+ T cell development are rediscovered and about a dozen new TFs are also identified. Sox4, Bhlhe40, Bach2 and Runx2 are experimentally verified and Bach2 is further shown to promote both development and recall proliferation of memory CD8+ T cells through Prdm1 and Id3. Gene perturbation study identifies the mode of interactions among the TFs with Sox4 as a hub. The identified TFs and insights into their interactions should facilitate further dissection of molecular mechanisms underlying memory CD8+ T cell development. PMID:24335726

  8. The lysophosphatidylserine receptor GPR174 constrains regulatory T cell development and function

    PubMed Central

    Barnes, Michael J.; Li, Chien-Ming; Xu, Ying; An, Jinping; Huang, Yong

    2015-01-01

    Regulatory T cell (T reg cell) numbers and activities are tightly calibrated to maintain immune homeostasis, but the mechanisms involved are incompletely defined. Here, we report that the lysophosphatidylserine (LysoPS) receptor GPR174 is abundantly expressed in developing and mature T reg cells. In mice that lacked this X-linked gene, T reg cell generation in the thymus was intrinsically favored, and a higher fraction of peripheral T reg cells expressed CD103. LysoPS could act in vitro via GPR174 to suppress T cell proliferation and T reg cell generation. In vivo, LysoPS was detected in lymphoid organ and spinal cord tissues and was abundant in the colon. Gpr174−/Y mice were less susceptible to experimental autoimmune encephalomyelitis than wild-type mice, and GPR174 deficiency in T reg cells contributed to this phenotype. This study provides evidence that a bioactive lipid, LysoPS, negatively influences T reg cell accumulation and activity through GPR174. As such, GPR174 antagonists might have therapeutic potential for promoting immune regulation in the context of autoimmune disease. PMID:26077720

  9. Macrophage and T cell dynamics during the development and disintegration of mycobacterial granulomas.

    PubMed

    Egen, Jackson G; Rothfuchs, Antonio Gigliotti; Feng, Carl G; Winter, Nathalie; Sher, Alan; Germain, Ronald N

    2008-02-01

    Granulomas play a key role in host protection against mycobacterial pathogens, with their breakdown contributing to exacerbated disease. To better understand the initiation and maintenance of these structures, we employed both high-resolution multiplex static imaging and intravital multiphoton microscopy of Mycobacterium bovis BCG-induced liver granulomas. We found that Kupffer cells directly capture blood-borne bacteria and subsequently nucleate formation of a nascent granuloma by recruiting both uninfected liver-resident macrophages and blood-derived monocytes. Within the mature granuloma, these myeloid cell populations formed a relatively immobile cellular matrix that interacted with a highly dynamic effector T cell population. The efficient recruitment of these T cells was highly dependent on TNF-alpha-derived signals, which also maintained the granuloma structure through preferential effects on uninfected macrophage populations. By characterizing the migration of both innate and adaptive immune cells throughout the process of granuloma development, these studies provide a new perspective on the cellular events involved in mycobacterial containment and escape. PMID:18261937

  10. The lysophosphatidylserine receptor GPR174 constrains regulatory T cell development and function.

    PubMed

    Barnes, Michael J; Li, Chien-Ming; Xu, Ying; An, Jinping; Huang, Yong; Cyster, Jason G

    2015-06-29

    Regulatory T cell (T reg cell) numbers and activities are tightly calibrated to maintain immune homeostasis, but the mechanisms involved are incompletely defined. Here, we report that the lysophosphatidylserine (LysoPS) receptor GPR174 is abundantly expressed in developing and mature T reg cells. In mice that lacked this X-linked gene, T reg cell generation in the thymus was intrinsically favored, and a higher fraction of peripheral T reg cells expressed CD103. LysoPS could act in vitro via GPR174 to suppress T cell proliferation and T reg cell generation. In vivo, LysoPS was detected in lymphoid organ and spinal cord tissues and was abundant in the colon. Gpr174(-/Y) mice were less susceptible to experimental autoimmune encephalomyelitis than wild-type mice, and GPR174 deficiency in T reg cells contributed to this phenotype. This study provides evidence that a bioactive lipid, LysoPS, negatively influences T reg cell accumulation and activity through GPR174. As such, GPR174 antagonists might have therapeutic potential for promoting immune regulation in the context of autoimmune disease. PMID:26077720

  11. Development of an IFNγ ELISPOT for the analysis of the human T cell response against mumps virus.

    PubMed

    Han, Wanda G H; Emmelot, Maarten E; Jaadar, Haziz; Ten Hulscher, Hinke I; van Els, Cécile A C M; Kaaijk, Patricia

    2016-04-01

    In the last decade, mumps virus (MuV) causes outbreaks in highly vaccinated populations. Sub-optimal T cell immunity may play a role in the susceptibility to mumps in vaccinated individuals. T cell responses to mumps virus have been demonstrated, yet the quality of the MuV-specific T cell response has not been analyzed using single cell immunological techniques. Here we developed an IFNγ ELISPOT assay to assess MuV-specific T cell responses in peripheral blood mononuclear cells (PBMC) of healthy (vaccinated) donors and mumps patients. Various in vitro MuV-specific stimulation methods of PBMC were compared, using either live or inactivated MuV alone or MuV-infected autologous antigen presenting cells, i.e. Epstein Barr Virus-transformed B lymphoblastoid cell lines (EBV-BLCL) or (mitogen pre-activated) PBMC, for their ability to recall IFNγ-producing responder cells measured by ELISPOT. For the detection of MuV-specific T cell responses, direct exposure (24h) to live MuV was the preferred stimulation method when assay sensitivity and practical reasons were considered. Notably, flowcytometric confirmation of data revealed that primarily T cells and NK cells produce IFNγ upon live MuV stimulation. Depleting PBMC from CD56(+) NK cells prior to stimulation with live MuV led to the enumeration of MuV-specific T cell responses by ELISPOT. Our assay constitutes a tool to evaluate memory MuV-specific T cell responses in MuV vaccinated or infected persons. Furthermore, this study provides evidence that live MuV not only induces IFNγ production by T cells, but also by NK cells. PMID:26872407

  12. 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

  13. 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.

  14. 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

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

    PubMed

    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

  16. FOXP3 and CEACAM6 expression and T cell infiltration in the occurrence and development of colon cancer

    PubMed Central

    LIU, YINGYING; XIA, TINGTING; JIN, CHUNHUI; GU, DONGMEI; YU, JIE; SHI, WEIQIANG; ZHANG, KE; ZHANG, LIPING; YE, JIANXIN; LI, LING

    2016-01-01

    The transcription factor forkhead box P3 (FOXP3) is involved in immune cell regulation, and carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) is an adhesion molecule of the immunoglobulin superfamily. These two genes are associated with cancer progression. In the current study, colon tissue specimens from 78 cases of colon cancer (including 40 of stage I–II and 38 of stage III–IV), 30 cases of colonic adenoma and 12 healthy controls were collected from the First Affiliated Hospital of Soochow University between January 2010 and December 2011. The expression of cluster of differentiation (CD) 3, CD4, CD8, CD45RO, CEACAM6 and FOXP3 in colon tissues was examined by immunohistochemical analysis. In addition, a reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assay, based on SYBR Green I, was used to detect CD3, CD4, CD8, CD45RO, CEACAM6 and FOXP3 mRNA levels in the paraffin block specimens. CD3+, CD8+ and CD45RO+ T cell infiltrations in colonic adenoma were significantly higher than in normal colonic mucosa (P<0.001, P=0.001 and P<0.001, respectively). However, CD3+, CD8+ and CD45RO+ lymphocytes in stage III–IV colon cancer tissues were lower than in normal control tissues (P=0.015, P=0.002 and P=0.041, respectively); consistently, CD3+, CD4+, CD8+ and CD45RO+ lymphocytes in stage III–IV tissues were even more markedly lower compared with adenoma (P=0.001, P<0.001, P<0.001 and P<0.001, respectively). Similarly, CD3+, CD8+ and CD45RO+ T cell infiltration was lower in stage I–II cancer tissues compared with adenoma (P=0.001, P<0.001 and P<0.001). CD3+, CD4+, CD8+ and CD45RO+ T cell infiltrations were also significantly higher in stage I–II compared with stage III–IV cancer tissues (P<0.001, P=0.045, P<0.001 and P<0.001, respectively). CEACAM6 was found to gradually increase from normal colon tissue to adenoma and cancer tissue. FOXP3 was expressed more highly in stage I–II compared with normal tissues (P=0.014), and

  17. Diacylglycerol Kinases: Regulated Controllers of T Cell Activation, Function, and Development

    PubMed Central

    Joshi, Rohan P.; Koretzky, Gary A.

    2013-01-01

    Diacylglycerol kinases (DGKs) are a diverse family of enzymes that catalyze the conversion of diacylglycerol (DAG), a crucial second messenger of receptor-mediated signaling, to phosphatidic acid (PA). Both DAG and PA are bioactive molecules that regulate a wide set of intracellular signaling proteins involved in innate and adaptive immunity. Clear evidence points to a critical role for DGKs in modulating T cell activation, function, and development. More recently, studies have elucidated factors that control DGK function, suggesting an added complexity to how DGKs act during signaling. This review summarizes the available knowledge of the function and regulation of DGK isoforms in signal transduction with a particular focus on T lymphocytes. PMID:23531532

  18. H-2 restriction as a consequence of intentional priming: T cells of fully allogeneic chimeric mice as well as of normal mice respond to foreign antigens in the context of H-2 determinants not encountered on thymic epithelial cells.

    PubMed

    Stockinger, H; Pfizenmaier, K; Hardt, C; Rodt, H; Röllinghoff, M; Wagner, H

    1980-12-01

    Fully allogeneic chimeras were able to develop in vitro alloantigen-specific, as well as H-2-restricted, Sendai virus-specific cytotoxic T-lymphocyte (CTL) response. Depending on the immunization regimen used, Sendai virus-specific CTL responses were restricted to the H-2 antigens of either the stem cell donor or the thymus. Similarly, unprimed splenic T cells of normal mice were found to contain CTL-precursor cells that specifically reacted against Sendai virus or trinitrophenyl derivatives in the context of allogeneic major histocompatibility complex determinants that had not been encountered during their thymic differentiation. A frequency analysis of allogeneically versus syngeneically restricted virus-specific CTL precursors present in splenic T cells showed a ratio of about 1 to 6. These results provide evidence that H-2 restriction of trinitrophenyl- or Sendai virus-specific T cells is dictated by the complex type of the antigen-presenting cell and thus appears to be independent of the type of thymus in which the T cells have undergone maturation. PMID:6261255

  19. 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 CD8α+ 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 CD8α+, 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

  20. Expression and regulation of lincRNAs during T cell development and differentiation

    PubMed Central

    Hu, Gangqing; Tang, Qingsong; Sharma, Suveena; Yu, Fang; Escobar, Thelma M.; Muljo, Stefan A.; Zhu, Jinfang; Zhao, Keji

    2013-01-01

    Although lincRNAs are implicated in gene regulation in various tissues, little is known about lincRNA transcriptomes in the T cell lineages. Here we identify 1,524 lincRNA clusters in 42 T cell samples from early T cell progenitors to terminally differentiated T helper (TH) subsets. Our analysis revealed highly dynamic and cell-specific expression patterns of lincRNAs during T cell differentiation. Importantly, these lincRNAs are located in genomic regions enriched for protein-coding genes with immune-regulatory functions. Many of them are bound and regulated by the key T cell transcription factors T-bet, GATA-3, STAT4 and STAT6. We demonstrate that the lincRNA LincR-Ccr2-5′AS, together with GATA-3, is an essential component of a regulatory circuit in TH2-specific gene expression and important for TH2 cell migration. PMID:24056746

  1. [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

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

    PubMed Central

    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.

    2015-01-01

    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

  3. T cell- but not tumor cell-produced TGF-β1 promotes the development of spontaneous mammary cancer

    PubMed Central

    Sarkar, Abira; Donkor, Moses K.; Li, Ming O.

    2011-01-01

    During their development, tumors acquire multiple capabilities that enable them to proliferate, disseminate and evade immunosurveillance. A putative mechanism is through the production of the cytokine TGF-β1. We showed in our recent studies that T cell-produced TGF-β1 inhibits antitumor T cell responses to foster tumor growth raising the question of the precise function of TGF-β1 produced by tumor cells in tumor development. Here, using a transgenic model of mammary cancer, we report that deletion of TGF-β1 from tumor cells did not protect mice from tumor development. However, ablation of TGF-β1 from T cells significantly inhibited mammary tumor growth. Additionally, absence of TGF-β1 in T cells prevented tumors from advancing to higher pathological grades and further suppressed secondary tumor development in the lungs. These findings reveal T cells but not tumor cells as a critical source of TGF-β1 that promotes tumor development. PMID:22248703

  4. Development of a diverse human T-cell repertoire despite stringent restriction of hematopoietic clonality in the thymus

    PubMed Central

    Brugman, Martijn H.; Wiekmeijer, Anna-Sophia; van Eggermond, Marja; Wolvers-Tettero, Ingrid; Langerak, Anton W.; de Haas, Edwin F. E.; Bystrykh, Leonid V.; van Rood, Jon J.; de Haan, Gerald; Fibbe, Willem E.; Staal, Frank J. T.

    2015-01-01

    The fate and numbers of hematopoietic stem cells (HSC) and their progeny that seed the thymus constitute a fundamental question with important clinical implications. HSC transplantation is often complicated by limited T-cell reconstitution, especially when HSC from umbilical cord blood are used. Attempts to improve immune reconstitution have until now been unsuccessful, underscoring the need for better insight into thymic reconstitution. Here we made use of the NOD-SCID-IL-2Rγ−/− xenograft model and lentiviral cellular barcoding of human HSCs to study T-cell development in the thymus at a clonal level. Barcoded HSCs showed robust (>80% human chimerism) and reproducible myeloid and lymphoid engraftment, with T cells arising 12 wk after transplantation. A very limited number of HSC clones (<10) repopulated the xenografted thymus, with further restriction of the number of clones during subsequent development. Nevertheless, T-cell receptor rearrangements were polyclonal and showed a diverse repertoire, demonstrating that a multitude of T-lymphocyte clones can develop from a single HSC clone. Our data imply that intrathymic clonal fitness is important during T-cell development. As a consequence, immune incompetence after HSC transplantation is not related to the transplantation of limited numbers of HSC but to intrathymic events. PMID:26483497

  5. CD4 T-cell activation and reduced regulatory T-cell populations are associated with early development of cataracts among HIV-infected adults in Uganda

    PubMed Central

    Nakanjako, Damalie; Otiti-Sengeri, Juliet; Ssewanyana, Isaac; Nabatanzi, Rose; Bayigga, Lois; Kirimunda, Samuel; Joloba, Moses; Manabe, Yukari C.; Kambugu, Andrew; Colebunders, Robert; Mayanja-Kizza, Harriet

    2016-01-01

    Background Cataracts contribute 12% of visual loss among HIV-infected adults in Uganda. Immuno-pathogenesis of cataracts may differ among HIV-infected individuals; thus the need for innovative therapeutic interventions among HIV-infected adults. Methods In a laboratory based case-control study, nested in a clinical/surgical community outreach camp, 50 adults with cataracts eligible for surgery were selected consecutively. HIV testing was done for individuals with unknown HIV sero-status. Peripheral Blood Mononuclear Cells (PBMC) were collected from all HIV-positive-adults-with-cataracts (cases) and HIV-negative-adults-with-cataracts (comparative group) and age-matched HIV-negative and HIV-positive- adults- without-cataracts (comparative group). Treg were measured as CD3+CD4+FoxP3+CD25+bright and immune activation as CD3+CD4+CD38+HALDR+ using a Facs Canto II flowcytometer. Mann Whitney test was used to compare expression among the four groups. Results Of 50 adults operated for cataracts, 24 (48%) were female, 25(50%) were HIV-positive. HIV-positive-individuals had cataracts earlier [median; Inter-quartile Range (IQR); 49(44-53) years] than HIV-negative [70 (IQR 59-75) years]; p=0.0005.Treg were lower among individuals with cataracts irrespective of HIV status; p=0.001; but comparable among younger HIV-positive and elderly HIV-negative with cataracts; p=0.301. Immune activation levels were comparable among HIV-positive and HIV-negative individuals with cataracts. However, HIV-positive-individuals with cataracts expressed higher levels of immune activation than HIV-positive-individuals without cataracts; p=0.012 and HIV-negative-individuals-with-cataracts expressed higher levels of immune activation that HIV-negative-without-cataracts; p<0.0001. Conclusion CD4 T-cell activation and reduced regulatory T-cell populations were associated with cataracts among adults aging with HIV. We recommend studies on clinical relevance of immune modulation in the prevention of early

  6. Breast cancer instructs dendritic cells to prime interleukin 13-secreting CD4+ T cells that facilitate tumor development.

    PubMed

    Aspord, Caroline; Pedroza-Gonzalez, Alexander; Gallegos, Mike; Tindle, Sasha; Burton, Elizabeth C; Su, Dan; Marches, Florentina; Banchereau, Jacques; Palucka, A Karolina

    2007-05-14

    We previously reported (Bell, D., P. Chomarat, D. Broyles, G. Netto, G.M. Harb, S. Lebecque, J. Valladeau, J. Davoust, K.A. Palucka, and J. Banchereau. 1999. J. Exp. Med. 190: 1417-1426) that breast cancer tumors are infiltrated with mature dendritic cells (DCs), which cluster with CD4(+) T cells. We now show that CD4(+) T cells infiltrating breast cancer tumors secrete type 1 (interferon gamma) as well as high levels of type 2 (interleukin [IL] 4 and IL-13) cytokines. Immunofluorescence staining of tissue sections revealed intense IL-13 staining on breast cancer cells. The expression of phosphorylated signal transducer and activator of transcription 6 in breast cancer cells suggests that IL-13 actually delivers signals to cancer cells. To determine the link between breast cancer, DCs, and CD4(+) T cells, we implanted human breast cancer cell lines in nonobese diabetic/LtSz-scid/scid beta2 microglobulin-deficient mice engrafted with human CD34(+) hematopoietic progenitor cells and autologous T cells. There, CD4(+) T cells promote early tumor development. This is dependent on DCs and can be partially prevented by administration of IL-13 antagonists. Thus, breast cancer targets DCs to facilitate its development. PMID:17438063

  7. 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.

  8. CD4 T cells with effector memory phenotype and function develop in the sterile environment of the fetus.

    PubMed

    Zhang, Xiaoming; Mozeleski, Brian; Lemoine, Sebastien; Dériaud, Edith; Lim, Annick; Zhivaki, Dania; Azria, Elie; Le Ray, Camille; Roguet, Gwenaelle; Launay, Odile; Vanet, Anne; Leclerc, Claude; Lo-Man, Richard

    2014-05-28

    The T cell compartment is considered to be naïve and dedicated to the development of tolerance during fetal development. We have identified and characterized a population of fetally developed CD4 T cells with an effector memory phenotype (TEM), which are present in cord blood. This population is polyclonal and has phenotypic features similar to those of conventional adult memory T cells, such as CD45RO expression. These cells express low levels of CD25 but are distinct from regulatory T cells because they lack Foxp3 expression. After T cell receptor activation, neonatal TEM cells readily produced tumor necrosis factor-α (TNF-α) and granulocyte-macrophage colony-stimulating factor (GM-CSF). We also detected interferon-γ (IFN-γ)-producing T helper 1 (TH1) cells and interleukin-4 (IL-4)/IL-13-producing TH2-like cells, but not IL-17-producing cells. We used chemokine receptor expression patterns to divide this TEM population into different subsets and identified distinct transcriptional programs using whole-genome microarray analysis. IFN-γ was found in CXCR3(+) TEM cells, whereas IL-4 was found in both CXCR3(+) TEM cells and CCR4(+) TEM cells. CCR6(+) TEM cells displayed a genetic signature that corresponded to TH17 cells but failed to produce IL-17A. However, the TH17 function of TEM cells was observed in the presence of IL-1β and IL-23. In summary, in the absence of reported pathology or any major infectious history, T cells with a memory-like phenotype develop in an environment thought to be sterile during fetal development and display a large variety of inflammatory effector functions associated with CD4 TH cells at birth. PMID:24871133

  9. From Murine to Human Nude/SCID: The Thymus, T-Cell Development and the Missing Link

    PubMed Central

    Romano, Rosa; Palamaro, Loredana; Fusco, Anna; Iannace, Leucio; Maio, Stefano; Vigliano, Ilaria; Giardino, Giuliana; Pignata, Claudio

    2012-01-01

    Primary immunodeficiencies (PIDs) are disorders of the immune system, which lead to increased susceptibility to infections. T-cell defects, which may affect T-cell development/function, are approximately 11% of reported PIDs. The pathogenic mechanisms are related to molecular alterations not only of genes selectively expressed in hematopoietic cells but also of the stromal component of the thymus that represents the primary lymphoid organ for T-cell differentiation. With this regard, the prototype of athymic disorders due to abnormal stroma is the Nude/SCID syndrome, first described in mice in 1966. In man, the DiGeorge Syndrome (DGS) has long been considered the human prototype of a severe T-cell differentiation defect. More recently, the human equivalent of the murine Nude/SCID has been described, contributing to unravel important issues of the T-cell ontogeny in humans. Both mice and human diseases are due to alterations of the FOXN1, a developmentally regulated transcription factor selectively expressed in skin and thymic epithelia. PMID:22474479

  10. 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.

  11. Effect of IL-4 on the Development and Function of Memory-like CD8 T Cells in the Peripheral Lymphoid Tissues.

    PubMed

    Park, Hi-Jung; Lee, Ara; Lee, Jae-Il; Park, Seong Hoe; Ha, Sang-Jun; Jung, Kyeong Cheon

    2016-04-01

    Unlike conventional T cells, innate CD8 T cells develop a memory-like phenotype in the thymus and immediately respond upon antigen stimulation, similar to memory T cells. The development of innate CD8 T cells in the thymus is known to require IL-4, which upregulates Eomesodermin (Eomes). These features are similar to that of virtual memory CD8 T cells and IL-4-induced memory-like CD8 T cells generated in the peripheral tissues. However, the relationship between these cell types has not been clearly documented. In the present study, IL-4-induced memory-like CD8 T cells generated in the peripheral tissues were compared with innate CD8 T cells in terms of phenotype and function. When an IL-4/anti-IL-4 antibody complex (IL-4C) was injected into C57BL/6 mice daily for 7 days, the Eomes(hi)CXCR3 (+) CD8 T cell population was markedly increased in the peripheral lymphoid organs and blood. These cells were generated from naïve CD8 T cells or accumulated via the expansion of pre-existing CD44(hi)CXCR3 (+) CD8 T cells. Initially, the majority of these CXCR3 (+) CD8 T cells expressed low levels of CD44, which was followed by the conversion to the CD44(hi) phenotype. This conversion was associated with the acquisition of enhanced effector function. After discontinuation of IL-4C treatment, Eomes expression levels gradually decreased in CXCR3 (+) CD8 T cells. Taken together, the results of this study demonstrate that IL-4-induced memory-like CD8 T cells generated in the peripheral lymphoid tissues are phenotypically and functionally similar to the innate CD8 T cells generated in the thymus. PMID:27162529

  12. Effect of IL-4 on the Development and Function of Memory-like CD8 T Cells in the Peripheral Lymphoid Tissues

    PubMed Central

    Park, Hi-Jung; Lee, Ara; Lee, Jae-Il; Park, Seong Hoe

    2016-01-01

    Unlike conventional T cells, innate CD8 T cells develop a memory-like phenotype in the thymus and immediately respond upon antigen stimulation, similar to memory T cells. The development of innate CD8 T cells in the thymus is known to require IL-4, which upregulates Eomesodermin (Eomes). These features are similar to that of virtual memory CD8 T cells and IL-4-induced memory-like CD8 T cells generated in the peripheral tissues. However, the relationship between these cell types has not been clearly documented. In the present study, IL-4-induced memory-like CD8 T cells generated in the peripheral tissues were compared with innate CD8 T cells in terms of phenotype and function. When an IL-4/anti-IL-4 antibody complex (IL-4C) was injected into C57BL/6 mice daily for 7 days, the EomeshiCXCR3 + CD8 T cell population was markedly increased in the peripheral lymphoid organs and blood. These cells were generated from naïve CD8 T cells or accumulated via the expansion of pre-existing CD44hiCXCR3 + CD8 T cells. Initially, the majority of these CXCR3 + CD8 T cells expressed low levels of CD44, which was followed by the conversion to the CD44hi phenotype. This conversion was associated with the acquisition of enhanced effector function. After discontinuation of IL-4C treatment, Eomes expression levels gradually decreased in CXCR3 + CD8 T cells. Taken together, the results of this study demonstrate that IL-4-induced memory-like CD8 T cells generated in the peripheral lymphoid tissues are phenotypically and functionally similar to the innate CD8 T cells generated in the thymus. PMID:27162529

  13. The Special Relationship in the Development and Function of T Helper 17 and Regulatory T Cells.

    PubMed

    Lochner, Matthias; Wang, Zuobai; Sparwasser, Tim

    2015-01-01

    T helper 17 (Th17) cells play an essential role in the clearance of extracellular pathogenic bacteria and fungi. However, this subset is critically involved in the pathology of many autoimmune diseases, e.g., psoriasis, multiple sclerosis, allergy, rheumatoid arthritis, and inflammatory bowel diseases in humans. Therefore, Th17 responses need to be tightly regulated in vivo to mediate effective host defenses against pathogens without causing excessive host tissue damage. Foxp3(+) regulatory T (Treg) cells play an important role in maintaining peripheral tolerance to self-antigens and in counteracting the inflammatory activity of effector T helper cell subsets. Although Th17 and Treg cells represent two CD4(+) T cell subsets with opposing principal functions, these cell types are functionally connected. In this review, we will first give an overview on the biology of Th17 cells and describe their development and in vivo function, followed by an account on the special developmental relationship between Th17 and Treg cells. We will describe the identification of Treg/Th17 intermediates and consider their lineage stability and function in vivo. Finally, we will discuss how Treg cells may regulate the Th17 cell response in the context of infection and inflammation, and elude on findings demonstrating that Treg cells can also have a prominent function in promoting the differentiation of Th17 cells. PMID:26615094

  14. [Development of new treatments for extranodal NK/T-cell lymphoma in Japan].

    PubMed

    Yamaguchi, Motoko

    2015-06-01

    Extranodal NK/T-cell lymphoma, nasal type (ENKL), accounts for less than 3% of malignant lymphomas in Japan. Based on the results of prospective clinical trials, ENKL treatment has dramatically improved during the last decade in Japan. The Lymphoma Study Group of the Japan Clinical Oncology Group (JCOG) conducted a phase I/II study (JCOG0211) of concurrent chemoradiotherapy for newly-diagnosed, localized ENKL. The trial showed an excellent 5-year overall survival rate (70%) and acceptable toxicity of RT-2/3DeVIC. The NK-cell Tumor Study Group in Japan, together with Asian collaborators, conducted clinical trials (SMILE-PI & PII) of SMILE chemotherapy for patients with newly-diagnosed stage IV, or relapsed/refractory ENKL. The overall response rate for 2 cycles of SMILE in 38 evaluated patients was 79%. The 2013 Japanese Society of Hematology guidelines recommend RT-2/3DeVIC for the treatment of newly-diagnosed ENKL of stage IE and contiguous stage IIE with cervical node involvement. For other ENKL, SMILE or other L-asparaginase-containing chemotherapies are recommended. A large retrospective study evaluating the efficacy and toxicity of these new treatments in clinical practice is currently underway in Japan. Close cooperation between radiation oncologists and international collaboration will be the key factors in developing better first-line treatments for ENKL. PMID:26256873

  15. Programmed cell death 1 inhibits inflammatory helper T-cell development through controlling the innate immune response.

    PubMed

    Rui, Yuxiang; Honjo, Tasuku; Chikuma, Shunsuke

    2013-10-01

    Programmed cell death 1 (PD-1) is an inhibitory coreceptor on immune cells and is essential for self-tolerance because mice genetically lacking PD-1 (PD-1(-/-)) develop spontaneous autoimmune diseases. PD-1(-/-) mice are also susceptible to severe experimental autoimmune encephalomyelitis (EAE), characterized by a massive production of effector/memory T cells against myelin autoantigen, the mechanism of which is not fully understood. We found that an increased primary response of PD-1(-/-) mice to heat-killed mycobacteria (HKMTB), an adjuvant for EAE, contributed to the enhanced production of T-helper 17 (Th17) cells. Splenocytes from HKMTB-immunized, lymphocyte-deficient PD-1(-/-) recombination activating gene (RAG)2(-/-) mice were found to drive antigen-specific Th17 cell differentiation more efficiently than splenocytes from HKMTB-immunized PD-1(+/+) RAG2(-/-) mice. This result suggested PD-1's involvement in the regulation of innate immune responses. Mice reconstituted with PD-1(-/-) RAG2(-/-) bone marrow and PD-1(+/+) CD4(+) T cells developed more severe EAE compared with the ones reconstituted with PD-1(+/+) RAG2(-/-) bone marrow and PD-1(+/+) CD4(+) T cells. We found that upon recognition of HKMTB, CD11b(+) macrophages from PD-1(-/-) mice produced very high levels of IL-6, which helped promote naive CD4(+) T-cell differentiation into IL-17-producing cells. We propose a model in which PD-1 negatively regulates antimycobacterial responses by suppressing innate immune cells, which in turn prevents autoreactive T-cell priming and differentiation to inflammatory effector T cells. PMID:24043779

  16. KAP1 Regulates Gene Networks Controlling T cell Development and Responsiveness

    PubMed Central

    Santoni de Sio, F.R.; Barde, I.; Offner, S.; Kapopoulou, A.; Genolet, R.; Corsinotti, A.; Bojkowska, K.; Thomas, J.H.; Luescher, I.; Pinschewer, D.; Harris, N.; Trono, D.

    2016-01-01

    The modulation of chromatin status at specific genomic loci controls lymphoid differentiation. Here, we investigated the role played in this process by KAP1, the universal cofactor of KRAB-containing zinc finger proteins (KRAB-ZFP), a tetrapod-restricted family of transcriptional repressors. T lymphoid KAP1 knockout mice displayed expansions of specific T cell populations, with impaired responses to stimulation and deregulation of genes involved in cell survival, cytoskeletal rearrangement, and immune signalling. Furthermore, chromatin studies demonstrate that KAP1 directly regulates the expression of a number of these genes, among which Foxo1 seemed of particular interest. Likely at least partly responsible for these effects, a small number of KRAB/ZFPs are selectively expressed in T cells. These results reveal the as-of-yet unsuspected importance of the KRAB/KAP1 epigenetic regulation system for T cell differentiation and function. PMID:22872677

  17. Lipopeptides of Borrelia burgdorferi outer surface proteins induce Th1 phenotype development in alphabeta T-cell receptor transgenic mice.

    PubMed Central

    Infante-Duarte, C; Kamradt, T

    1997-01-01

    Induction of the appropriate T helper cell (Th) subset is crucial for the resolution of infectious diseases and the prevention of immunopathology. Some pathogens preferentially induce Th1 or Th2 responses. How microorganisms influence Th phenotype development is unknown. We asked if Borrelia burgdorferi, the spirochete which causes Lyme arthritis, can promote a cytokine milieu in which T cells which are not specific for B. burgdorferi are induced to produce proinflammatory cytokines. Using alphabeta T-cell receptor transgenic mice as a source of T cells with a defined specificity other than for B. burgdorferi, we found that B. burgdorferi induced Th1 phenotype development in ovalbumin-specific transgenic T cells. Small synthetic lipopeptides corresponding to the N-terminal sequences of B. burgdorferi outer surface lipoproteins had similar effects. B. burgdorferi and its lipopeptides induced host cells to produce interleukin-12. When the peptides were used in delipidated form, they did not induce Th1 development. These findings may be of pathogenic importance, since it is currently assumed that a Th2-mediated antibody response is protective against B. burgdorferi. Bacteria associated with reactive arthritis, namely, Yersinia enterocolitica, Shigella flexneri, and Salmonella enteritidis, had different effects. The molecular definition of pathogen-host interactions determining cytokine production should facilitate rational therapeutic interventions directing the host response towards the desired cytokine response. Here, we describe small synthetic molecules capable of inducing Th1 phenotype development. PMID:9317013

  18. 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 ...

  19. Contribution of JAK2 mutations to T-cell lymphoblastic lymphoma development

    PubMed Central

    Roncero, A M; López-Nieva, P; Cobos-Fernández, M A; Villa-Morales, M; González-Sánchez, L; López-Lorenzo, J L; Llamas, P; Ayuso, C; Rodríguez-Pinilla, S M; Arriba, M C; Piris, M A; Fernández-Navarro, P; Fernández, A F; Fraga, M F; Santos, J; Fernández-Piqueras, J

    2016-01-01

    The JAK-STAT pathway has a substantial role in lymphoid precursor cell proliferation, survival and differentiation. Nonetheless, the contribution of JAK2 to T-cell lymphoblastic lymphoma (T-LBL) development remains poorly understood. We have identified one activating TEL-JAK2 translocation and four missense mutations accumulated in 2 out of 16 T-LBL samples. Two of them are novel JAK2 mutations and the other two are reported for the first time in T-LBL. Notably, R683G and I682T might have arisen owing to RNA editing. Mutated samples showed different mutated transcripts suggesting sub-clonal heterogeneity. Functional approaches revealed that two JAK2 mutations (H574R and R683G) constitutively activate JAK-STAT signaling in γ2A cells and can drive the proliferation of BaF3-EpoR cytokine-dependent cell line. In addition, aberrant hypermethylation of SOCS3 might contribute to enhance the activation of JAK-STAT signaling. Of utmost interest is that primary T-LBL samples harboring JAK2 mutations exhibited increased expression of LMO2, suggesting a mechanistic link between JAK2 mutations and the expression of LMO2, which was confirmed for the four missense mutations in transfected γ2A cells. We therefore propose that active JAK2 contribute to T-LBL development by two different mechanisms, and that the use of pan-JAK inhibitors in combination with epigenetic drugs should be considered in future treatments. PMID:26216197

  20. Contribution of JAK2 mutations to T-cell lymphoblastic lymphoma development.

    PubMed

    Roncero, A M; López-Nieva, P; Cobos-Fernández, M A; Villa-Morales, M; González-Sánchez, L; López-Lorenzo, J L; Llamas, P; Ayuso, C; Rodríguez-Pinilla, S M; Arriba, M C; Piris, M A; Fernández-Navarro, P; Fernández, A F; Fraga, M F; Santos, J; Fernández-Piqueras, J

    2016-01-01

    The JAK-STAT pathway has a substantial role in lymphoid precursor cell proliferation, survival and differentiation. Nonetheless, the contribution of JAK2 to T-cell lymphoblastic lymphoma (T-LBL) development remains poorly understood. We have identified one activating TEL-JAK2 translocation and four missense mutations accumulated in 2 out of 16 T-LBL samples. Two of them are novel JAK2 mutations and the other two are reported for the first time in T-LBL. Notably, R683G and I682T might have arisen owing to RNA editing. Mutated samples showed different mutated transcripts suggesting sub-clonal heterogeneity. Functional approaches revealed that two JAK2 mutations (H574R and R683G) constitutively activate JAK-STAT signaling in γ2A cells and can drive the proliferation of BaF3-EpoR cytokine-dependent cell line. In addition, aberrant hypermethylation of SOCS3 might contribute to enhance the activation of JAK-STAT signaling. Of utmost interest is that primary T-LBL samples harboring JAK2 mutations exhibited increased expression of LMO2, suggesting a mechanistic link between JAK2 mutations and the expression of LMO2, which was confirmed for the four missense mutations in transfected γ2A cells. We therefore propose that active JAK2 contribute to T-LBL development by two different mechanisms, and that the use of pan-JAK inhibitors in combination with epigenetic drugs should be considered in future treatments. PMID:26216197

  1. Human T cell leukemia virus type I and neurologic disease: events in bone marrow, peripheral blood, and central nervous system during normal immune surveillance and neuroinflammation.

    PubMed

    Grant, Christian; Barmak, Kate; Alefantis, Timothy; Yao, Jing; Jacobson, Steven; Wigdahl, Brian

    2002-02-01

    Human T cell lymphotropic/leukemia virus type I (HTLV-I) has been identified as the causative agent of both adult T cell leukemia (ATL) and HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Although the exact sequence of events that occur during the early stages of infection are not known in detail, the initial route of infection may predetermine, along with host, environmental, and viral factors, the subset of target cells and/or the primary immune response encountered by HTLV-I, and whether an HTLV-I-infected individual will remain asymptomatic, develop ATL, or progress to the neuroinflammatory disease, HAM/TSP. Although a large number of studies have indicated that CD4(+) T cells represent an important target for HTLV-I infection in the peripheral blood (PB), additional evidence has accumulated over the past several years demonstrating that HTLV-I can infect several additional cellular compartments in vivo, including CD8(+) T lymphocytes, PB monocytes, dendritic cells, B lymphocytes, and resident central nervous system (CNS) astrocytes. More importantly, extensive latent viral infection of the bone marrow, including cells likely to be hematopoietic progenitor cells, has been observed in individuals with HAM/TSP as well as some asymptomatic carriers, but to a much lesser extent in individuals with ATL. Furthermore, HTLV-I(+) CD34(+) hematopoietic progenitor cells can maintain the intact proviral genome and initiate viral gene expression during the differentiation process. Introduction of HTLV-I-infected bone marrow progenitor cells into the PB, followed by genomic activation and low level viral gene expression may lead to an increase in proviral DNA load in the PB, resulting in a progressive state of immune dysregulation including the generation of a detrimental cytotoxic Tax-specific CD8(+) T cell population, anti-HTLV-I antibodies, and neurotoxic cytokines involved in disruption of myelin-producing cells and neuronal degradation

  2. Secondary Epstein-Barr virus associated lymphoproliferative disorder developing in a patient with angioimmunoblastic T cell lymphoma on vorinostat.

    PubMed

    Smeltzer, Jacob P; Viswanatha, David S; Habermann, Thomas M; Patnaik, Mrinal M

    2012-09-01

    Ebstein-Barr Virus (EBV)-related lymphoproliferative disorders primarily occur in the setting of immunosuppression, most commonly after solid organ transplantation. The frequency depends on the degree of immunosuppression and the specific organ transplanted, but can be as high as 3–9% in heart or lung transplant patients. Less frequent outside of the transplant setting, EBV-related lymphoproliferative disorders classified as other iatrogenic immunodeficiency associated lymphoproliferative disorders in the WHO Classification, which are different than iatrogenically related lymphomas supervening on hematological malignancies, have been associated with other immunosuppressive therapies such as 6-Mercaptopurine, azathioprine, or alemtuzumab. These disorders have also been reported to develop spontaneously in patients with T cell lymphomas (angioimmunoblastic and peripheral T cell NOS). Here we report the case of a patient with an angioimmunoblastic T cell lymphoma on therapy with vorinostat who developed an EBV related B-cell lymphoproliferative disorder involving bilateral adrenal glands. Angioimmunoblastic T cell lymphoma is associated with severe immunodeficiency and risk for opportunistic infections. This immune dysregulation has been implicated in its association with EBV related lymphoproliferative disorders. In this patient, vorinostat therapy also appears to be linked to the development of an EBV-related lymphoproliferative disorder. PMID:22718468

  3. PROGRESSION OF REGULATORY GENE EXPRESSION STATES IN FETAL AND ADULT PRO-T CELL DEVELOPMENT

    PubMed Central

    David-Fung, Elizabeth-Sharon; Yui, Mary A.; Morales, Marissa; Wang, Hua; Taghon, Tom; Diamond, Rochelle A.; Rothenberg, Ellen V.

    2014-01-01

    Precursors entering the T-cell developmental pathway traverse a progression of states characterized by distinctive patterns of gene expression. Of particular interest are regulatory genes, which ultimately control the dwell time of cells in each state and establish the mechanisms that propel them forward to subsequent states. Under particular genetic and developmental circumstances, the transitions between these states occur with different timing, and environmental feedbacks may shift the steady-state accumulations of cells in each state. The fetal transit through pro-T cell stages is faster than in the adult, and subject to somewhat different genetic requirements. To explore causes of such variation, this review presents previously unpublished data on differentiation gene activation in pro-T cells of pre-TCR deficient mutant mice, and a quantitative comparison of the profiles of transcription factor gene expression in pro-T cell subsets of fetal and adult wildtype mice. Against a background of consistent gene expression, several regulatory genes show marked differences between fetal and adult expression profiles, including those encoding two bHLH antagonist Id factors, the Ets family factor SpiB, and the Notch target gene Deltex1. The results also reveal global differences in regulatory alterations triggered by the first TCR-dependent selection events in fetal and adult thymopoiesis. PMID:16448545

  4. Modeling altered T-cell development with induced pluripotent stem cells from patients with RAG1-dependent immune deficiencies.

    PubMed

    Brauer, Patrick M; Pessach, Itai M; Clarke, Erik; Rowe, Jared H; Ott de Bruin, Lisa; Lee, Yu Nee; Dominguez-Brauer, Carmen; Comeau, Anne M; Awong, Geneve; Felgentreff, Kerstin; Zhang, Yuhang H; Bredemeyer, Andrea; Al-Herz, Waleed; Du, Likun; Ververs, Francesca; Kennedy, Marion; Giliani, Silvia; Keller, Gordon; Sleckman, Barry P; Schatz, David G; Bushman, Frederic D; Notarangelo, Luigi D; Zúñiga-Pflücker, Juan Carlos

    2016-08-11

    Primary immunodeficiency diseases comprise a group of heterogeneous genetic defects that affect immune system development and/or function. Here we use in vitro differentiation of human induced pluripotent stem cells (iPSCs) generated from patients with different recombination-activating gene 1 (RAG1) mutations to assess T-cell development and T-cell receptor (TCR) V(D)J recombination. RAG1-mutants from severe combined immunodeficient (SCID) patient cells showed a failure to sustain progression beyond the CD3(--)CD4(-)CD8(-)CD7(+)CD5(+)CD38(-)CD31(-/lo)CD45RA(+) stage of T-cell development to reach the CD3(-/+)CD4(+)CD8(+)CD7(+)CD5(+)CD38(+)CD31(+)CD45RA(-) stage. Despite residual mutant RAG1 recombination activity from an Omenn syndrome (OS) patient, similar impaired T-cell differentiation was observed, due to increased single-strand DNA breaks that likely occur due to heterodimers consisting of both an N-terminal truncated and a catalytically dead RAG1. Furthermore, deep-sequencing analysis of TCR-β (TRB) and TCR-α (TRA) rearrangements of CD3(-)CD4(+)CD8(-) immature single-positive and CD3(+)CD4(+)CD8(+) double-positive cells showed severe restriction of repertoire diversity with preferential usage of few Variable, Diversity, and Joining genes, and skewed length distribution of the TRB and TRA complementary determining region 3 sequences from SCID and OS iPSC-derived cells, whereas control iPSCs yielded T-cell progenitors with a broadly diversified repertoire. Finally, no TRA/δ excision circles (TRECs), a marker of TRA/δ locus rearrangements, were detected in SCID and OS-derived T-lineage cells, consistent with a pre-TCR block in T-cell development. This study compares human T-cell development of SCID vs OS patients, and elucidates important differences that help to explain the wide range of immunologic phenotypes that result from different mutations within the same gene of various patients. PMID:27301863

  5. 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

  6. Normal psychomotor development.

    PubMed

    Cioni, Giovanni; Sgandurra, Giuseppina

    2013-01-01

    "Psychomotor" development refers to changes in a child's cognitive, emotional, motor, and social capacities from the beginning of life throughout fetal and neonatal periods, infancy, childhood, and adolescence. It occurs in a variety of domains and a wide range of theories makes understanding children's development a challenging undertaking. Different models have tried to interpret the origins of human behavior, the pattern of developmental changes over time, and the individual and contextual factors that could direct child development. No single theory has been able to account for all aspects of child development, but each of them may contribute an important piece to the child development puzzle. Although theories sometimes disagree, much of their information is complementary rather than contradictory. The knowledge of child typical development and related theories and models is greatly useful for clinical practice, leading to recognition of developmental disorders and the ways in which they can be approached and treated. In this chapter, traditional and more modern concepts around functional development of psychomotor abilities are reported, firstly more in general and then specifically in the motor domain. PMID:23622146

  7. T cell receptor signal strength in Treg and iNKT cell development demonstrated by a novel fluorescent reporter mouse

    PubMed Central

    Moran, Amy E.; Holzapfel, Keli L.; Xing, Yan; Cunningham, Nicole R.; Maltzman, Jonathan S.; Punt, Jennifer

    2011-01-01

    The ability of antigen receptors to engage self-ligands with varying affinity is crucial for lymphocyte development. To further explore this concept, we generated transgenic mice expressing GFP from the immediate early gene Nr4a1 (Nur77) locus. GFP was up-regulated in lymphocytes by antigen receptor stimulation but not by inflammatory stimuli. In T cells, GFP was induced during positive selection, required major histocompatibility complex for maintenance, and directly correlated with the strength of T cell receptor (TCR) stimulus. Thus, our results define a novel tool for studying antigen receptor activation in vivo. Using this model, we show that regulatory T cells (Treg cells) and invariant NKT cells (iNKT cells) perceived stronger TCR signals than conventional T cells during development. However, although Treg cells continued to perceive strong TCR signals in the periphery, iNKT cells did not. Finally, we show that Treg cell progenitors compete for recognition of rare stimulatory TCR self-ligands. PMID:21606508

  8. Themis1 enhances T cell receptor signaling during thymocyte development by promoting Vav1 activity and Grb2 stability.

    PubMed

    Zvezdova, Ekaterina; Mikolajczak, Judith; Garreau, Anne; Marcellin, Marlène; Rigal, Lise; Lee, Jan; Choi, Seeyoung; Blaize, Gaëtan; Argenty, Jérémy; Familiades, Julien; Li, Liqi; Gonzalez de Peredo, Anne; Burlet-Schiltz, Odile; Love, Paul E; Lesourne, Renaud

    2016-01-01

    The T cell signaling protein Themis1 is essential for the positive and negative selection of thymocytes in the thymus. Although the developmental defect that results from the loss of Themis1 suggests that it enhances T cell receptor (TCR) signaling, Themis1 also recruits Src homology 2 domain-containing phosphatase-1 (SHP-1) to the vicinity of TCR signaling complexes, suggesting that it has an inhibitory role in TCR signaling. We used TCR signaling reporter mice and quantitative proteomics to explore the role of Themis1 in developing T cells. We found that Themis1 acted mostly as a positive regulator of TCR signaling in vivo when receptors were activated by positively selecting ligands. Proteomic analysis of the Themis1 interactome identified SHP-1, the TCR-associated adaptor protein Grb2, and the guanine nucleotide exchange factor Vav1 as the principal interacting partners of Themis1 in isolated mouse thymocytes. Analysis of TCR signaling in Themis1-deficient and Themis1-overexpressing mouse thymocytes demonstrated that Themis1 promoted Vav1 activity both in vitro and in vivo. The reduced activity of Vav1 and the impaired T cell development in Themis1(-/-) mice were due in part to increased degradation of Grb2, which suggests that Themis1 is required to maintain the steady-state abundance of Grb2 in thymocytes. Together, these data suggest that Themis1 acts as a positive regulator of TCR signaling in developing T cells, and identify a mechanism by which Themis1 regulates thymic selection. PMID:27188442

  9. Regulation of the transcriptional program by DNA methylation during human αβ T-cell development

    PubMed Central

    Rodriguez, Ramon M.; Suarez-Alvarez, Beatriz; Mosén-Ansorena, David; García-Peydró, Marina; Fuentes, Patricia; García-León, María J.; Gonzalez-Lahera, Aintzane; Macias-Camara, Nuria; Toribio, María L.; Aransay, Ana M.; Lopez-Larrea, Carlos

    2015-01-01

    Thymocyte differentiation is a complex process involving well-defined sequential developmental stages that ultimately result in the generation of mature T-cells. In this study, we analyzed DNA methylation and gene expression profiles at successive human thymus developmental stages. Gain and loss of methylation occurred during thymocyte differentiation, but DNA demethylation was much more frequent than de novo methylation and more strongly correlated with gene expression. These changes took place in CpG-poor regions and were closely associated with T-cell differentiation and TCR function. Up to 88 genes that encode transcriptional regulators, some of whose functions in T-cell development are as yet unknown, were differentially methylated during differentiation. Interestingly, no reversion of accumulated DNA methylation changes was observed as differentiation progressed, except in a very small subset of key genes (RAG1, RAG2, CD8A, PTCRA, etc.), indicating that methylation changes are mostly unique and irreversible events. Our study explores the contribution of DNA methylation to T-cell lymphopoiesis and provides a fine-scale map of differentially methylated regions associated with gene expression changes. These can lay the molecular foundations for a better interpretation of the regulatory networks driving human thymopoiesis. PMID:25539926

  10. 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

  11. Splenic Long-Lived Plasma Cells Promote the Development of Follicular Helper T Cells during Autoimmune Responses.

    PubMed

    Jang, Eunkyeong; Cho, Wang Sik; Oh, Yeon-Kyung; Cho, Mi-La; Kim, Jung Mogg; Paik, Doo-Jin; Youn, Jeehee

    2016-02-01

    Long-lived plasma cells (LLPCs) develop under the help of follicular helper T (Tfh) cells and reside mainly in the bone marrow. However, these cells are unusually abundant in the spleen of several autoimmune models including K/BxNsf mice, yet their pathogenic impact remains unknown. To investigate a previously unappreciated role of splenic LLPCs, we sorted splenic plasma cells (PCs) from K/BxNsf and K/BxN mice, corresponding to LLPCs and conventional short-lived PCs, respectively, and compared their phenotypes and ability to prime and induce the differentiation of naive CD4(+) T cells into effector cells in vitro and in vivo. We found that K/BxNsf PCs had lower levels of the Ag presentation machinery and costimulators than K/BxN PCs, and also a lower CD4(+) T cell priming capacity. Autoantigen-pulsed K/BxNsf PCs selectively polarized cognate CD4(+) T cells toward the expression of molecules necessary for Tfh development and function. As a result, the K/BxNsf PC-primed CD4(+) T cells were more effective in stimulating B cells to produce autoantigen-specific IgGs than K/BxN PCs or even dendritic cells. Adoptive transfer of K/BxNsf PCs, but not K/BxN PCs, to K/BxN mice increased numbers of Tfh cells in draining lymph nodes. These results propose that abnormal accumulation of LLPCs in the spleen of autoimmune models drives the differentiation of autoantigen-primed CD4(+) T cells to Tfh cells. This positive feedback loop between splenic LLPCs and Tfh cells may contribute to the persistence of humoral autoimmunity. PMID:26729802

  12. Development of the neonatal B and T cell repertoire in swine: implications for comparative and veterinary immunology.

    PubMed

    Butler, John E; Sinkora, Marek; Wertz, Nancy; Holtmeier, Wolfgang; Lemke, Caitlin D

    2006-01-01

    Birth in all higher vertebrates is at the center of the critical window of development in which newborns transition from dependence on innate immunity to dependence on their own adaptive immunity, with passive maternal immunity bridging this transition. Therefore we have studied immunological development through fetal and early neonatal life. In swine, B cells appear earlier in fetal development than T cells. B cell development begins in the yolk sac at the 20th day of gestation (DG20), progresses to fetal liver at DG30 and after DG45 continues in bone marrow. The first wave of developing T cells is gammadelta cells expressing a monomorphic Vdelta rearrangement. Thereafter, alphabeta T cells predominate and at birth, at least 19 TRBV subgroups are expressed, 17 of which appear highly homologous with those in humans. In contrast to the T cell repertoire and unlike humans and mice, the porcine pre-immune VH (IGHV-D-J) repertoire is highly restricted, depending primarily on CDR3 for diversity. The V-KAPPA (IGKV-J) repertoire and apparently also the V-LAMBDA (IGLV-J) repertoire, are also restricted. Diversification of the pre-immune B cell repertoire of swine and the ability to respond to both T-dependent and T-independent antigen depends on colonization of the gut after birth in which colonizing bacteria stimulate with Toll-like receptor ligands, especially bacterial DNA. This may explain the link between repertoire diversification and the anatomical location of primary lymphoid tissue like the ileal Peyers patches. Improper development of adaptive immunity can be caused by infectious agents like the porcine reproductive and respiratory syndrome virus that causes immune dysregulation resulting in immunological injury and autoimmunity. PMID:16611556

  13. 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.

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

    PubMed Central

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

    2000-01-01

    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+ 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-2Rα and IL-7Rα genes were ectopically transcribed in CD4+CD8+ 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. PMID:10716941

  15. CXXC finger protein 1 is critical for T-cell intrathymic development through regulating H3K4 trimethylation

    PubMed Central

    Cao, Wenqiang; Guo, Jing; Wen, Xiaofeng; Miao, Li; Lin, Feng; Xu, Guanxin; Ma, Ruoyu; Yin, Shengxia; Hui, Zhaoyuan; Chen, Tingting; Guo, Shixin; Chen, Wei; Huang, Yingying; Liu, Yizhi; Wang, Jianli; Wei, Lai; Wang, Lie

    2016-01-01

    T-cell development in the thymus is largely controlled by an epigenetic program, involving in both DNA methylation and histone modifications. Previous studies have identified Cxxc1 as a regulator of both cytosine methylation and histone 3 lysine 4 trimethylation (H3K4me3). However, it is unknown whether Cxxc1 plays a role in thymocyte development. Here we show that T-cell development in the thymus is severely impaired in Cxxc1-deficient mice. Furthermore, we identify genome-wide Cxxc1-binding sites and H3K4me3 modification sites in wild-type and Cxxc1-deficient thymocytes. Our results demonstrate that Cxxc1 directly controls the expression of key genes important for thymocyte survival such as RORγt and for T-cell receptor signalling including Zap70 and CD8, through maintaining the appropriate H3K4me3 on their promoters. Importantly, we show that RORγt, a direct target of Cxxc1, can rescue the survival defects in Cxxc1-deficient thymocytes. Our data strongly support a critical role of Cxxc1 in thymocyte development. PMID:27210293

  16. CXXC finger protein 1 is critical for T-cell intrathymic development through regulating H3K4 trimethylation.

    PubMed

    Cao, Wenqiang; Guo, Jing; Wen, Xiaofeng; Miao, Li; Lin, Feng; Xu, Guanxin; Ma, Ruoyu; Yin, Shengxia; Hui, Zhaoyuan; Chen, Tingting; Guo, Shixin; Chen, Wei; Huang, Yingying; Liu, Yizhi; Wang, Jianli; Wei, Lai; Wang, Lie

    2016-01-01

    T-cell development in the thymus is largely controlled by an epigenetic program, involving in both DNA methylation and histone modifications. Previous studies have identified Cxxc1 as a regulator of both cytosine methylation and histone 3 lysine 4 trimethylation (H3K4me3). However, it is unknown whether Cxxc1 plays a role in thymocyte development. Here we show that T-cell development in the thymus is severely impaired in Cxxc1-deficient mice. Furthermore, we identify genome-wide Cxxc1-binding sites and H3K4me3 modification sites in wild-type and Cxxc1-deficient thymocytes. Our results demonstrate that Cxxc1 directly controls the expression of key genes important for thymocyte survival such as RORγt and for T-cell receptor signalling including Zap70 and CD8, through maintaining the appropriate H3K4me3 on their promoters. Importantly, we show that RORγt, a direct target of Cxxc1, can rescue the survival defects in Cxxc1-deficient thymocytes. Our data strongly support a critical role of Cxxc1 in thymocyte development. PMID:27210293

  17. Rational development of high-affinity T-cell receptor-like antibodies.

    PubMed

    Stewart-Jones, Guillaume; Wadle, Andreas; Hombach, Anja; Shenderov, Eugene; Held, Gerhard; Fischer, Eliane; Kleber, Sascha; Nuber, Natko; Stenner-Liewen, Frank; Bauer, Stefan; McMichael, Andrew; Knuth, Alexander; Abken, Hinrich; Hombach, Andreas A; Cerundolo, Vincenzo; Jones, E Yvonne; Renner, Christoph

    2009-04-01

    T-cell interaction with a target cell is a key event in the adaptive immune response and primarily driven by T-cell receptor (TCR) recognition of peptide-MHC (pMHC) complexes. TCR avidity for a given pMHC is determined by number of MHC molecules, availability of coreceptors, and TCR affinity for MHC or peptide, respectively, with peptide recognition being the most important factor to confer target specificity. Here we present high-resolution crystal structures of 2 Fab antibodies in complex with the immunodominant NY-ESO-1(157-165) peptide analogue (SLLMWITQV) presented by HLA-A*0201 and compare them with a TCR recognizing the same pMHC. Binding to the central methionine-tryptophan peptide motif and orientation of binding were almost identical for Fabs and TCR. As the MW "peg" dominates the contacts between Fab and peptide, we estimated the contributions of individual amino acids between the Fab and peptide to provide the rational basis for a peptide-focused second-generation, high-affinity antibody library. The final Fab candidate achieved better peptide binding by 2 light-chain mutations, giving a 20-fold affinity improvement to 2-4 nM, exceeding the affinity of the TCR by 1,000-fold. The high-affinity Fab when grafted as recombinant TCR on T cells conferred specific killing of HLA-A*0201/NY-ESO-1(157-165) target cells. In summary, we prove that affinity maturation of antibodies mimicking a TCR is possible and provide a strategy for engineering high-affinity antibodies that can be used in targeting specific pMHC complexes for diagnostic and therapeutic purposes. PMID:19307587

  18. Rational development of high-affinity T-cell receptor-like antibodies

    PubMed Central

    Stewart-Jones, Guillaume; Wadle, Andreas; Hombach, Anja; Shenderov, Eugene; Held, Gerhard; Fischer, Eliane; Kleber, Sascha; Nuber, Natko; Stenner-Liewen, Frank; Bauer, Stefan; McMichael, Andrew; Knuth, Alexander; Abken, Hinrich; Hombach, Andreas A.; Cerundolo, Vincenzo; Jones, E. Yvonne; Renner, Christoph

    2009-01-01

    T-cell interaction with a target cell is a key event in the adaptive immune response and primarily driven by T-cell receptor (TCR) recognition of peptide-MHC (pMHC) complexes. TCR avidity for a given pMHC is determined by number of MHC molecules, availability of coreceptors, and TCR affinity for MHC or peptide, respectively, with peptide recognition being the most important factor to confer target specificity. Here we present high-resolution crystal structures of 2 Fab antibodies in complex with the immunodominant NY-ESO-1157–165 peptide analogue (SLLMWITQV) presented by HLA-A*0201 and compare them with a TCR recognizing the same pMHC. Binding to the central methionine-tryptophan peptide motif and orientation of binding were almost identical for Fabs and TCR. As the MW “peg” dominates the contacts between Fab and peptide, we estimated the contributions of individual amino acids between the Fab and peptide to provide the rational basis for a peptide-focused second-generation, high-affinity antibody library. The final Fab candidate achieved better peptide binding by 2 light-chain mutations, giving a 20-fold affinity improvement to 2–4 nM, exceeding the affinity of the TCR by 1,000-fold. The high-affinity Fab when grafted as recombinant TCR on T cells conferred specific killing of HLA-A*0201/NY-ESO-1157–165 target cells. In summary, we prove that affinity maturation of antibodies mimicking a TCR is possible and provide a strategy for engineering high-affinity antibodies that can be used in targeting specific pMHC complexes for diagnostic and therapeutic purposes. PMID:19307587

  19. Essential role for caspase 8 in T-cell homeostasis and T-cell-mediated immunity

    PubMed Central

    Salmena, Leonardo; Lemmers, Benedicte; Hakem, Anne; Matysiak-Zablocki, Elzbieta; Murakami, Kiichi; Au, P.Y. Billie; Berry, Donna M.; Tamblyn, Laura; Shehabeldin, Amro; Migon, Eva; Wakeham, Andrew; Bouchard, Denis; Yeh, Wen Chen; McGlade, Jane C.; Ohashi, Pamela S.; Hakem, Razqallah

    2003-01-01

    Defects in death receptor-mediated apoptosis have been linked to cancer and autoimmune disease in humans. The in vivo role of caspase 8, a component of this pathway, has eluded analysis in postnatal tissues because of the lack of an appropriate animal model. Targeted disruption of caspase 8 is lethal in utero. We generated mice with a targeted caspase 8 mutation that is restricted to the T-cell lineage. Despite normal thymocyte development in the absence of caspase 8, we observed a marked decrease in the number of peripheral T-cells and impaired T-cell response ex vivo to activation stimuli. caspase 8 ablation protected thymocytes and activated T-cells from CD95 ligand but not anti-CD3-induced apoptosis, or apoptosis activated by agents that are known to act through the mitochondria. caspase 8 mutant mice were unable to mount an immune response to viral infection, indicating that caspase 8 deletion in T-cells leads to immunodeficiency. These findings identify an essential, cell-stage-specific role for caspase 8 in T-cell homeostasis and T-cell-mediated immunity. This is consistent with the recent identification of caspase 8 mutations in human immunodeficiency. PMID:12654726

  20. Regulatory T cells: a review.

    PubMed

    Dasgupta, Alakananda; Saxena, Renu

    2012-01-01

    Regulatory T cells (Tregs) play a pivotal role in the homeostasis of the immune system and in the modulation of the immune response. Tregs have emerged as key players in the development and maintenance of peripheral immune tolerance. Broadly speaking, CD4+ T cells possessing the ability to suppress immune responses can be divided into two types: naturally occurring (nTreg) and inducible (iTreg) or adaptive regulatory cells. Naturally occurring thymus-derived CD4+CD25+ Tregs are a subset of T cells which have immunosuppressive properties and are 5%-10% of the total peripheral CD4+ T cells. In normal conditions, Tregs regulate ongoing immune responses and prevent autoimmunity. Imbalanced function or number of these cells, either enhanced or decreased, might lead to tumour development and autoimmunity, respectively. These cells thus play a major role in autoimmune diseases, transplantation tolerance, infectious diseases, allergic disease and tumour immunity. These natural properties make Tregs attractive tools for novel immunotherapeutic approaches. The in vivo manipulation or depletion of Tregs may help devise effective immunotherapy for patients with cancer, autoimmunity, graftversus-host disease, infectious diseases and allergic diseases. It is crucial to understand the biology of Tregs before attempting therapies, including (i) the injection of expanded Tregs to cure autoimmune disease or prevent graft-versus-host disease or (ii) the depletion or inhibition of Tregs in cancer therapy. Recent findings in murine models and studies in humans have opened new avenues to study the biology of Tregs and their therapeutic potential. This overview provides a framework for integrating these concepts of basic and translational research. PMID:23998865

  1. Insulinoma-released exosomes or microparticles are immunostimulatory and can activate autoreactive T cells spontaneously developed in nonobese diabetic mice.

    PubMed

    Sheng, Huiming; Hassanali, Saleema; Nugent, Courtney; Wen, Li; Hamilton-Williams, Emma; Dias, Peter; Dai, Yang D

    2011-08-15

    Exosomes (EXO) are secreted intracellular microparticles that can trigger inflammation and induce Ag-specific immune responses. To test possible roles of EXO in autoimmunity, we isolated small microparticles, mainly EXO, from mouse insulinoma and examined their activities to stimulate the autoimmune responses in NOD mice, a model for human type 1 diabetes. We demonstrate that the EXO contains strong innate stimuli and expresses candidate diabetes autoantigens. They can induce secretion of inflammatory cytokines through a MyD88-dependent pathway, and activate purified APC and result in T cell proliferation. To address whether EXO or the secreted microparticles are possible autoimmune targets causing islet-specific inflammation, we monitored the T cell responses spontaneously developed in prediabetic NOD mice for their reactivity to the EXO, and compared this reactivity between diabetes-susceptible and -resistant congenic mouse strains. We found that older NOD females, which have advanced islet destruction, accumulated more EXO-reactive, IFN-γ-producing lymphocytes than younger females or age-matched males, and that pancreatic lymph nodes from the prediabetic NOD, but not from the resistant mice, were also enriched with EXO-reactive Th1 cells. In vivo, immunization with the EXO accelerates insulitis development in nonobese diabetes-resistant mice. Thus, EXO or small microparticles can be recognized by the diabetes-associated autoreactive T cells, supporting that EXO might be a possible autoimmune target and/or insulitis trigger in NOD or congenic mouse strains. PMID:21734072

  2. Virtual memory T cells develop and mediate bystander protective immunity in an IL-15-dependent manner.

    PubMed

    White, Jason T; Cross, Eric W; Burchill, Matthew A; Danhorn, Thomas; McCarter, Martin D; Rosen, Hugo R; O'Connor, Brian; Kedl, Ross M

    2016-01-01

    Virtual memory cells (VM) are an antigen-specific, memory phenotype CD8 T-cell subset found in lymphoreplete, unchallenged mice. Previous studies indicated that VM cells were the result of homeostatic proliferation (HP) resembling the proliferation observed in a lymphopenic environment. Here we demonstrate that HP is ongoing in lymphoreplete mice, the degree of which is dictated by the number of naive CD8 T cells with a sufficiently high affinity for self-antigen interacting with peripheral IL-15. VM cell transcriptional profiles suggest a capacity to mediate protective immunity via antigen non-specific bystander killing, a function we show is dependent on IL-15. Finally, we show a VM-like population of human cells that accumulate with age and traffic to the liver, displaying phenotypic and functional attributes consistent with the bystander protective functions of VM cells identified in the mouse. These data identify developmental and functional attributes of VM cells, including their likely role in protective immunity. PMID:27097762

  3. Gallium maltolate inhibits human cutaneous T-cell lymphoma tumor development in mice.

    PubMed

    Wu, Xuesong; Wang, Timothy W; Lessmann, George M; Saleh, Jamal; Liu, Xiping; Chitambar, Christopher R; Hwang, Sam T

    2015-03-01

    Cutaneous T-cell lymphomas (CTCLs) represent a heterogeneous group of non-Hodgkin's lymphoma characterized by an accumulation of malignant CD4 T cells in the skin. The group IIIa metal salt, gallium nitrate, is known to have antineoplastic activity against B-cell lymphoma in humans, but its activity in CTCLs has not been elaborated in detail. Herein, we examined the antineoplastic efficacy of a gallium compound, gallium maltolate (GaM), in vitro and in vivo with murine models of CTCLs. GaM inhibited cell growth and induced apoptosis of cultured CTCL cells. In human CTCL xenograft models, peritumoral injection of GaM limited the growth of CTCL cells, shown by fewer tumor formations, smaller tumor sizes, and decreased neovascularization in tumor microenvironment. To identify key signaling pathways that have a role in GaM-mediated reduction of tumor growth, we analyzed inflammatory cytokines, as well as signal transduction pathways in CTCL cells treated by GaM. IFN-γ-induced chemokines and IL-13 were found to be notably increased in GaM-treated CTCL cells. However, immunosuppressive cytokines, such as IL-10, were decreased with GaM treatment. Interestingly, both oxidative stress and p53 pathways were involved in GaM-induced cytotoxicity. These results warrant further investigation of GaM as a therapeutic agent for CTCLs. PMID:25371972

  4. Virtual memory T cells develop and mediate bystander protective immunity in an IL-15-dependent manner

    PubMed Central

    White, Jason T.; Cross, Eric W.; Burchill, Matthew A.; Danhorn, Thomas; McCarter, Martin D.; Rosen, Hugo R.; O'Connor, Brian; Kedl, Ross M.

    2016-01-01

    Virtual memory cells (VM) are an antigen-specific, memory phenotype CD8 T-cell subset found in lymphoreplete, unchallenged mice. Previous studies indicated that VM cells were the result of homeostatic proliferation (HP) resembling the proliferation observed in a lymphopenic environment. Here we demonstrate that HP is ongoing in lymphoreplete mice, the degree of which is dictated by the number of naive CD8 T cells with a sufficiently high affinity for self-antigen interacting with peripheral IL-15. VM cell transcriptional profiles suggest a capacity to mediate protective immunity via antigen non-specific bystander killing, a function we show is dependent on IL-15. Finally, we show a VM-like population of human cells that accumulate with age and traffic to the liver, displaying phenotypic and functional attributes consistent with the bystander protective functions of VM cells identified in the mouse. These data identify developmental and functional attributes of VM cells, including their likely role in protective immunity. PMID:27097762

  5. Distinct Signaling of Coreceptors Regulates Specific Metabolism Pathways and Impacts Memory Development in CAR T Cells.

    PubMed

    Kawalekar, Omkar U; O'Connor, Roddy S; Fraietta, Joseph A; Guo, Lili; McGettigan, Shannon E; Posey, Avery D; Patel, Prachi R; Guedan, Sonia; Scholler, John; Keith, Brian; Snyder, Nathaniel W; Snyder, Nathaniel; Blair, Ian A; Blair, Ian; Milone, Michael C; June, Carl H

    2016-02-16

    Chimeric antigen receptors (CARs) redirect T cell cytotoxicity against cancer cells, providing a promising approach to cancer immunotherapy. Despite extensive clinical use, the attributes of CAR co-stimulatory domains that impact persistence and resistance to exhaustion of CAR-T cells remain largely undefined. Here, we report the influence of signaling domains of coreceptors CD28 and 4-1BB on the metabolic characteristics of human CAR T cells. Inclusion of 4-1BB in the CAR architecture promoted the outgrowth of CD8(+) central memory T cells that had significantly enhanced respiratory capacity, increased fatty acid oxidation and enhanced mitochondrial biogenesis. In contrast, CAR T cells with CD28 domains yielded effector memory cells with a genetic signature consistent with enhanced glycolysis. These results provide, at least in part, a mechanistic insight into the differential persistence of CAR-T cells expressing 4-1BB or CD28 signaling domains in clinical trials and inform the design of future CAR T cell therapies. PMID:26885860

  6. The Ets protein Spi-B is expressed exclusively in B cells and T cells during development.

    PubMed

    Su, G H; Ip, H S; Cobb, B S; Lu, M M; Chen, H M; Simon, M C

    1996-07-01

    Spi-B and PU.1 are hematopoietic-specific transcription factors that constitute a subfamily of the Ets family of DNA-binding proteins. Here we show that contrary to previous reports, PU.1 and Spi-B have very different expression patterns. PU.1 is expressed at high levels in B cells, mast cells, megakaryocytes, macrophages, neutrophils, and immature erythroid cells and at lower levels in mature erythrocytes. PU.1 is completely absent from peripheral T cells and most T cell lines based on sensitive RT-PCR assays. In contrast, Spi-B is expressed exclusively in lymphoid cells and can be detected in early fetal thymus and spleen. In situ hybridizations of adult murine tissues demonstrate Spi-B mRNA in the medulla of the thymus, the white pulp of the spleen, and the germinal centers of lymph nodes. Spi-B expression is very abundant in B cells and both Spi-B mRNA and protein are detected in some T cells. In situ hybridization and Northern blot analysis suggest that Spi-B gene expression increases during B cell maturation and decreases during T cell maturation. Gel-retardation experiments show that Spi-B can bind to all putative PU.1 binding sites, but do not reveal any preferred Spi-B binding site. Finally, both PU.1 and Spi-B function as transcriptional activators of the immunoglobulin light-chain enhancer E lambda 2.4 when coexpressed with Pip (PU.1-interaction partner) in NIH-3T3 cells. Taken together, these data suggest that differences in patterns of expression between Spi-B and PU.1 distinguish the function of each protein during development of the immune system. PMID:8691135

  7. Relationship between T cell subpopulations and the mitogen responsiveness and suppressor cell function of peripheral blood mononuclear cells in normal individuals.

    PubMed Central

    Victorino, R M; Hodgson, H J

    1980-01-01

    A simultaneous analysis was made of numbers and proportions of T cell subsets (T mu and T gamma cells), lymphocyte responsiveness to non-specific mitogens in vitro and 'short-lived suppressor cell activity' in peripheral blood mononuclear cells (PBMC) of normal individuals. No correlation was found between either T gamma or T mu cells and the 'short-lived suppressor cell activity', suggesting that suppression in this system is not a reflection of quantitative alteration in these subsets. However, a highly significant positive correlation was found between numbers of T mu cells and PBMC responses to the mitogens phytohaemagglutinin, concanavalin A and pokeweek mitogen. This may reflect either a helper effect of T mu cells on lymphocyte proliferation in response to mitogens or the presence of the majority of mitogen-responsive cells within this subpopulation. As in normal individuals lymphocyte responsiveness correlates with the number of circulating T mu cells, it is possible that a reduction in these cells in disease states may contribute to defects in cell-mediated immunity. PMID:6452237

  8. Development of a luciferase based viral inhibition assay to evaluate vaccine induced CD8 T-cell responses

    PubMed Central

    Naarding, Marloes A.; Fernandez-Fernandez, Natalia; Kappes, John C.; Hayes, Peter; Ahmed, Tina; Icyuz, Mert; Edmonds, Tara G.; Bergin, Philip; Anzala, Omu; Hanke, Tomas; Clark, Lorna; Cox, Josephine H.; Cormier, Emmanuel; Ochsenbauer, Christina; Gilmour, Jill

    2014-01-01

    Emergence of SIV and HIV specific CD8 T cells has been shown to correlate with control of in vivo replication. Poor correlation between IFN-γ ELISPOT responses and in vivo control of the virus has triggered the development of more relevant assays to assess functional HIV-1 specific CD8 T-cell responses for the evaluation and prioritization of new HIV-1 vaccine candidates. We previously established a viral inhibition assay (VIA) that measures the ability of vaccine-induced CD8 T-cell responses to inhibit viral replication in autologous CD4 T cells. In this assay, viral replication is determined by measuring p24 in the culture supernatant. Here we describe the development of a novel VIA, referred to as IMC LucR VIA that exploits replication-competent HIV-1 infectious molecular clones (IMCs) in which the complete proviral genome is strain-specific and which express the Renilla luciferase (LucR) gene to determine viral growth and inhibition. The introduction of the luciferase readout does provide significant improvement of the read out time. In addition to switching to the LucR read out, changes made to the overall protocol resulted in the miniaturization of the assay from a 48 to a 96-well plate format, which preserved sample and allowed for the introduction of replicates. The overall assay time was reduced from 13 to 8 days. The assay has a high degree of specificity, and the previously observed non-specific background inhibition in cells from HIV-1 negative volunteers has been reduced dramatically. Importantly, we observed an increase in positive responses, indicating an improvement in sensitivity compared to the original VIA. Currently, only a limited number of “whole-genome” IMC-LucR viruses are available and our efforts will focus on expanding the panel to better evaluate anti-viral breadth. Overall, we believe the IMC LucR VIA provides a platform to assess functional CD8 T-cell responses in large-scale clinical trial testing, which will enhance the ability

  9. Ex Vivo γ-Retroviral Gene Therapy of Dogs with X-linked Severe Combined Immunodeficiency and the Development of a Thymic T Cell Lymphoma

    PubMed Central

    Kennedy, Douglas R.; Hartnett, Brian J.; Kennedy, Jeffrey S.; Vernau, William; Moore, Peter F.; O’Malley, Thomas; Burkly, Linda C.; Henthorn, Paula S.; Felsburg, Peter J.

    2011-01-01

    We have previously shown that in vivo γ-retroviral gene therapy of dogs with X-linked severe combined immunodeficiency (XSCID) results in sustained T cell reconstitution and sustained marking in myeloid and B cells for up to 4 years with no evidence of any serious adverse effects. The purpose of this study was to determine whether ex vivo γ-retroviral gene therapy of XSCID dogs results in a similar outcome. Eight of 12 XSCID dogs treated with an average of dose of 5.8 × 106 transduced CD34+ cells/kg successfully engrafted producing normal numbers of gene-corrected CD45RA+ (naïve) T cells. However, this was followed by a steady decrease in CD45RA+ T cells, T cell diversity, and thymic output as measured by T cell receptor excision circles (TRECs) resulting in a T cell lymphopenia. None of the dogs survived past 11 months post treatment. At necropsy, few gene-corrected thymocytes were observed correlating with the TREC levels and one of the dogs was diagnosed with a thymic T cell lymphoma that was attributed to the gene therapy. This study highlights the outcome differences between the ex vivo and in vivo approach to γ-retroviral gene therapy and is the first to document a serious adverse event following gene therapy in a canine model of a human genetic disease. PMID:21536334

  10. T-Cell Immunity to Influenza in Older Adults: A Pathophysiological Framework for Development of More Effective Vaccines

    PubMed Central

    McElhaney, Janet E.; Kuchel, George A.; Zhou, Xin; Swain, Susan L.; Haynes, Laura

    2016-01-01

    One of the most profound public health consequences of immune senescence is reflected in an increased susceptibility to influenza and other acute respiratory illnesses, as well as a loss of influenza vaccine effectiveness in older people. Common medical conditions and mental and psychosocial health issues as well as degree of frailty and functional dependence accelerate changes associated with immune senescence. All contribute to the increased risk for complications of influenza infection, including pneumonias, heart diseases, and strokes that lead to hospitalization, disability, and death in the over 65 population. Changes in mucosal barrier mechanisms and both innate and adaptive immune functions converge in the reduced response to influenza infection, and lead to a loss of antibody-mediated protection against influenza with age. The interactions of immune senescence and reduced adaptive immune responses, persistent cytomegalovirus infection, inflammaging (chronic elevation of inflammatory cytokines), and dysregulated cytokine production, pose major challenges to the development of vaccines designed to improve T-cell-mediated immunity. In older adults, the goal of vaccination is more realistically targeted to providing clinical protection against disease rather than to inducing sterilizing immunity to infection. Standard assays of antibody titers correlate with protection against influenza illness but do not detect important changes in cellular immune mechanisms that correlate with vaccine-mediated protection against influenza in older people. This article will discuss: (i) the burden of influenza in older adults and how this relates to changes in T-cell function, (ii) age-related changes in different T-cell subsets and immunologic targets for improved influenza vaccine efficacy in older, and (iii) the development of correlates of clinical protection against influenza disease to expedite the process of new vaccine development for the 65 and older population

  11. IL-15 receptor α signaling constrains the development of IL-17-producing γδ T cells.

    PubMed

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

    2015-08-01

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

  12. Reprogramming the tumor microenvironment: tumor-induced immunosuppressive factors paralyze T cells

    PubMed Central

    Wu, Annie A; Drake, Virginia; Huang, Huai-Shiuan; Chiu, ShihChi; Zheng, Lei

    2015-01-01

    It has become evident that tumor-induced immuno-suppressive factors in the tumor microenvironment play a major role in suppressing normal functions of effector T cells. These factors serve as hurdles that limit the therapeutic potential of cancer immunotherapies. This review focuses on illustrating the molecular mechanisms of immunosuppression in the tumor microenvironment, including evasion of T-cell recognition, interference with T-cell trafficking, metabolism, and functions, induction of resistance to T-cell killing, and apoptosis of T cells. A better understanding of these mechanisms may help in the development of strategies to enhance the effectiveness of cancer immunotherapies. PMID:26140242

  13. Cytomegalovirus Infection Leads to Development of High Frequencies of Cytotoxic Virus-Specific CD4+ T Cells Targeted to Vascular Endothelium.

    PubMed

    Pachnio, Annette; Ciaurriz, Miriam; Begum, Jusnara; Lal, Neeraj; Zuo, Jianmin; Beggs, Andrew; Moss, Paul

    2016-09-01

    Cytomegalovirus (CMV) infection elicits a very strong and sustained intravascular T cell immune response which may contribute towards development of accelerated immune senescence and vascular disease in older people. Virus-specific CD8+ T cell responses have been investigated extensively through the use of HLA-peptide tetramers but much less is known regarding CMV-specific CD4+ T cells. We used a range of HLA class II-peptide tetramers to investigate the phenotypic and transcriptional profile of CMV-specific CD4+ T cells within healthy donors. We show that such cells comprise an average of 0.45% of the CD4+ T cell pool and can reach up to 24% in some individuals (range 0.01-24%). CMV-specific CD4+ T cells display a highly differentiated effector memory phenotype and express a range of cytokines, dominated by dual TNF-α and IFN-γ expression, although substantial populations which express IL-4 were seen in some donors. Microarray analysis and phenotypic expression revealed a profile of unique features. These include the expression of CX3CR1, which would direct cells towards fractalkine on activated endothelium, and the β2-adrenergic receptor, which could permit rapid response to stress. CMV-specific CD4+ T cells display an intense cytotoxic profile with high level expression of granzyme B and perforin, a pattern which increases further during aging. In addition CMV-specific CD4+ T cells demonstrate strong cytotoxic activity against antigen-loaded target cells when isolated directly ex vivo. PD-1 expression is present on 47% of cells but both the intensity and distribution of the inhibitory receptor is reduced in older people. These findings reveal the marked accumulation and unique phenotype of CMV-specific CD4+ T cells and indicate how such T cells may contribute to the vascular complications associated with CMV in older people. PMID:27606804

  14. MicroRNA223 promotes pathogenic T-cell development and autoimmune inflammation in central nervous system in mice.

    PubMed

    Satoorian, Tiffany; Li, Bo; Tang, Xiaolei; Xiao, Jidong; Xing, Weirong; Shi, Weixing; Lau, Kin-Hing William; Baylink, David J; Qin, Xuezhong

    2016-08-01

    Multiple sclerosis (MS) is an incurable central nervous system autoimmune disease. Understanding MS pathogenesis is essential for the development of new MS therapies. In the present study, we identified a novel microRNA (miR) that regulates experimental autoimmune encephalomyelitis (EAE), an animal model of MS. Expression of miR223 was up-regulated specifically in spinal cords and lymphoid organs but not in other examined tissues. A global miR223 knockout (miR223(-/-) ) in mice led to a significant delay in EAE onset, reduction in spinal cord lesion, and lessening of neurological symptoms. These protective effects could be reproduced in bone marrow chimeras reconstituted with miR223(-/-) haematopoietic stem cells. We also found that miR223 deficiency reduced T helper type 1 (Th1) and Th17 infiltration into spinal cords. To address underlying mechanisms, we investigated the role of miR223 in regulating the function, development and interaction of the major immune cells. Expression of the genes associated with dendritic cell (DC) activation (CD86 and MHC II) and Th1 and Th17 differentiation [interleukin-12 (IL-12) and IL-23, respectively] was significantly decreased in the spleens of miR223(-/-) mice bearing EAE. The miR223(-/-) DCs expressed significantly lower levels of basal and lipopolysaccharide-induced IL-12 and IL-23 compared with the wild-type DCs. These data are consistent with the observed lower efficiency of miR223(-/-) DCs to support Th1 and Th17 differentiation from naive T cells over-expressing an EAE antigen-specific T-cell receptor. Our data suggest that miR223 promotes EAE, probably through enhancing DC activation and subsequently the differentiation of naive T cells toward Th1 and Th17 effector cells. PMID:27083389

  15. T cell receptor interactions with class I heavy-chain influence T cell selection

    PubMed Central

    Kuhns, Scott T.; Tallquist, Michelle D.; Johnson, Aaron J.; Mendez-Fernandez, Yanice; Pease, Larry R.

    2000-01-01

    The interaction of the T cell receptor (TCR) with peptide in the binding site of the major histocompatibility complex molecule provides the basis for T cell recognition during immune surveillance, repertoire development, and tolerance. Little is known about the extent to which repertoire selection is influenced directly by variation of the structure of the class I heavy chain. We find that the 2C TCR, normally positively selected in the context of the Kb molecule, is minimally selected into the CD8 lineage in the absence of antigen-processing genes. This finding underscores the importance of peptides in determining the positive-selecting class I ligands in the thymus. In contrast, Kbm3, a variant class I molecule that normally exerts a negative selection pressure on 2C-bearing T cells, positively selects 2C transgenic T cells into the CD8 lineage in an antigen-processing gene-deficient environment. These findings indicate that structural changes in the heavy chain can have direct influence in T cell recognition, from which we conclude that the nature of TCR interaction with class I heavy chain influences the array of TCRs selected during development of the functional adult repertoire. PMID:10639152

  16. EMSA Eritin Drives Expansion of Regulatory T Cells and Promotes T Cells Differentiation in Irradiated Mice.

    PubMed

    Ibrahim, Mansur; Widjajanto, Edi; Widodo, M Aris; Sumitro, Sutiman B

    2016-07-01

    Sublethal irradiation therapy in cancer treatment causes generalized immunosuppression, which results in a range of DNA damage. We examined the significance of a polyherbal medicine called "EMSA Eritin" on immunological responses in sublethally irradiated mice focusing on the involvement of Treg, naïve T cell, and also the development and differentiation of T cells in thymus. Normal BALB/c mice were sublethally irradiated with dose of 600 rad. The irradiated mice were then orally administered by EMSA Eritin once a day at different doses: 1.04, 3.12, 9.37 mg/g body weight. The treatment was performed for 14 days. On day 15, immunological responses were observed by analyzing the status of Treg and differentiation of T cells in thymus. The administration of EMSA Eritin to irradiated mice resulted in a significant increase of pre T cells, Treg cells, and naïve T cells, which in general could maintain and normalize healthy condition in mice. PMID:26170134

  17. Proinsulin Expression Shapes the TCR Repertoire but Fails to Control the Development of Low-Avidity Insulin-Reactive CD8+ T Cells.

    PubMed

    Pearson, James A; Thayer, Terri C; McLaren, James E; Ladell, Kristin; De Leenheer, Evy; Phillips, Amy; Davies, Joanne; Kakabadse, Dimitri; Miners, Kelly; Morgan, Peter; Wen, Li; Price, David A; Wong, F Susan

    2016-06-01

    NOD mice, a model strain for human type 1 diabetes, express proinsulin (PI) in the thymus. However, insulin-reactive T cells escape negative selection, and subsequent activation of the CD8(+) T-cell clonotype G9C8, which recognizes insulin B15-23 via an αβ T-cell receptor (TCR) incorporating TRAV8-1/TRAJ9 and TRBV19/TRBJ2-3 gene rearrangements, contributes to the development of diabetes. In this study, we used fixed TRAV8-1/TRAJ9 TCRα-chain transgenic mice to assess the impact of PI isoform expression on the insulin-reactive CD8(+) T-cell repertoire. The key findings were: 1) PI2 deficiency increases the frequency of insulin B15-23-reactive TRBV19(+)CD8(+) T cells and causes diabetes; 2) insulin B15-23-reactive TRBV19(+)CD8(+) T cells are more abundant in the pancreatic lymph nodes of mice lacking PI1 and/or PI2; 3) overexpression of PI2 decreases TRBV19 usage in the global CD8(+) T-cell compartment; 4) a biased repertoire of insulin-reactive CD8(+) T cells emerges in the periphery regardless of antigen exposure; and 5) low-avidity insulin-reactive CD8(+) T cells are less affected by antigen exposure in the thymus than in the periphery. These findings inform our understanding of the diabetogenic process and reveal new avenues for therapeutic exploitation in type 1 diabetes. PMID:26953160

  18. Interferon-γ 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-γ-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-γ-producing cells enhance HBZ-mediated inflammation, since knocking out IFN-γ 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-γ-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

  19. Memory CD4 T cells emerge from effector T-cell progenitors.

    PubMed

    Harrington, Laurie E; Janowski, Karen M; Oliver, James R; Zajac, Allan J; Weaver, Casey T

    2008-03-20

    A hallmark of adaptive immunity is the generation of memory T cells that confer long-lived, antigen-specific protection against repeat challenges by pathogens. Understanding the mechanisms by which memory T cells arise is important for rational vaccination strategies and improved therapeutic interventions for chronic infections and autoimmune disorders. The large clonal expansion of CD8 T cells in response to some infections has made the development of CD8 T-cell memory more amenable to study, giving rise to a model of memory cell differentiation in which a fraction of fully competent effector T cells transition into long-lived memory T cells. Delineation of CD4 T-cell memory development has proved more difficult as a result of limitations on tracking the smaller populations of CD4 effector T cells generated during a pathogenic challenge, complicating efforts to determine whether CD4 memory T cells are direct descendants of effector T cells or whether they develop by alternative pathways. Here, using two complementary cytokine reporter mouse models to identify interferon (IFN)-gamma-positive effector T cells and track their fate, we show that the lineage relationship between effector and memory CD4 T cells resembles that for CD8 T cells responding to the same pathogen. We find that, in parallel with effector CD8 T cells, IFN-gamma-positive effector CD4 T cells give rise to long-lived memory T cells capable of anamnestic responses to antigenic rechallenge. PMID:18322463

  20. Overexpression of LMO2 causes aberrant human T-Cell development in vivo by three potentially distinct cellular mechanisms.

    PubMed

    Wiekmeijer, Anna-Sophia; Pike-Overzet, Karin; Brugman, Martijn H; van Eggermond, Marja C J A; Cordes, Martijn; de Haas, Edwin F E; Li, Yunlei; Oole, Edwin; van IJcken, Wilfred F J; Egeler, R Maarten; Meijerink, Jules P; Staal, Frank J T

    2016-09-01

    Overexpression of LMO2 is known to be one of the causes of T-cell acute lymphoblastic leukemia (T-ALL) development; however, the mechanisms behind its oncogenic activity are incompletely understood. LMO2-overexpressing transgenic mouse models suggest an accumulation of immature T-cell progenitors in the thymus as the main preleukemic event. The effects of LMO2 overexpression on human T-cell development in vivo are unknown. Here, we report studies of a humanized mouse model transplanted with LMO2-transduced human hematopoietic stem/progenitor cells. The effects of LMO2 overexpression were confined to the T-cell lineage; however, initially, multipotent cells were transduced. Three effects of LMO2 on human T-cell development were observed: (1) a block at the double-negative/immature single-positive stage, (2) an accumulation of CD4(+)CD8(+) double-positive CD3(-) cells, and (3) an altered CD8/CD4 ratio with enhanced peripheral T lymphocytes. Microarray analysis of sorted double-positive cells overexpressing LMO2 led to the identification of an LMO2 gene set that clustered with human T-ALL patient samples of the described "proliferative" cluster. In this article, we demonstrate previously unrecognized mechanisms by which LMO2 alters human T-cell development in vivo; these mechanisms correlate with human T-ALL leukemogenesis. PMID:27302866

  1. Stage-specific functions of E-proteins at the β-selection and T-cell receptor checkpoints during thymocyte development.

    PubMed

    Jones, Mary Elizabeth; Zhuang, Yuan

    2011-04-01

    The E-protein transcription factors E2A and HEB function in a lineage- and stage-specific manner to orchestrate many critical events throughout lymphocyte development. The function of E-proteins in both B- and T-lymphocyte development has been extensively studied through the use of single-gene knockout animals. Unlike B cells, which rely primarily on E2A alone, T cells are regulated by the combinatorial expression of both E2A and HEB. Therefore, many of the roles of E-proteins during T-cell development may be masked in single-gene knockout studies due to the compensatory function of E2A and HEB. More recently, our laboratory has established double-conditional knockout models to eliminate both E2A and HEB in a stage-specific manner throughout T-cell development. These models, in combination with other complimentary genetic approaches, have identified new E-protein functions at each of the two major T-cell developmental checkpoints. Here, we will discuss how E-proteins function to regulate the expression of T-cell receptor components and cell cycle at the β-selection checkpoint, and how they control positive selection, survival, and lineage-specific gene expression at the subsequent T-cell receptor checkpoint. PMID:21128008

  2. Osteonecrosis of the Jaw Developed in Mice: DISEASE VARIANTS REGULATED BY γδ T CELLS IN ORAL MUCOSAL BARRIER IMMUNITY.

    PubMed

    Park, Sil; Kanayama, Keiichi; Kaur, Kawaljit; Tseng, Han-Ching Helen; Banankhah, Sina; Quje, Davood Talebi; Sayre, James W; Jewett, Anahid; Nishimura, Ichiro

    2015-07-10

    Osteonecrosis of the jaw (ONJ), an uncommon co-morbidity in patients treated with bisphosphonates (BP), occurs in the segment of jawbone interfacing oral mucosa. This study aimed to investigate a role of oral mucosal barrier γδ T cells in the pathogenesis of ONJ. Female C57Bl/6J (B6) mice received a bolus zoledronate intravenous injection (ZOL, 540 μg/kg), and their maxillary left first molars were extracted 1 week later. ZOL-treated mice (WT ZOL) delayed oral wound healing with patent open wounds 4 weeks after tooth extraction with characteristic oral epithelial hyperplasia. γδ T cells appeared within the tooth extraction site and hyperplastic epithelium in WT ZOL mice. In ZOL-treated γδ T cell null (Tcrd(-/-) ZOL) mice, the tooth extraction open wound progressively closed; however, histological ONJ-like lesions were identified in 75 and 60% of WT ZOL and Tcrd(-/-) ZOL mice, respectively. Although the bone exposure phenotype of ONJ was predominantly observed in WT ZOL mice, Tcrd(-/-) ZOL mice developed the pustule/fistula disease phenotype. We further addressed the role of γδ T cells from human peripheral blood (h-γδ T cells). When co-cultured with ZOL-pretreated human osteoclasts in vitro, h-γδ T cells exhibited rapid expansion and robust IFN-γ secretion. When h-γδ T cells were injected into ZOL-treated immunodeficient (Rag2(-/-) ZOL) mice, the oral epithelial hyperplasia developed. However, Rag2(-/-) ZOL mice did not develop osteonecrosis. The results indicate that γδ T cells are unlikely to influence the core osteonecrosis mechanism; however, they may serve as a critical modifier contributing to the different oral mucosal disease variations of ONJ. PMID:26013832

  3. WT1-specific T cell receptor gene therapy: improving TCR function in transduced T cells.

    PubMed

    Stauss, Hans J; Thomas, Sharyn; Cesco-Gaspere, Michela; Hart, Daniel P; Xue, Shao-An; Holler, Angelika; King, Judy; Wright, Graham; Perro, Mario; Pospori, Constantina; Morris, Emma

    2008-01-01

    Adoptive transfer of antigen-specific T lymphocytes is an attractive form of immunotherapy for haematological malignancies and cancer. The difficulty of isolating antigen-specific T lymphocytes for individual patients limits the more widespread use of adoptive T cell therapy. The demonstration that cloned T cell receptor (TCR) genes can be used to produce T lymphocyte populations of desired specificity offers new opportunities for antigen-specific T cell therapy. The first trial in humans demonstrated that TCR gene-modified T cells persisted for an extended time period and reduced tumor burden in some patients. The WT1 protein is an attractive target for immunotherapy of leukemia and solid cancer since elevated expression has been demonstrated in AML, CML, MDS and in breast, colon and ovarian cancer. In the past, we have isolated high avidity CTL specific for a WT1-derived peptide presented by HLA-A2 and cloned the TCR alpha and beta genes of a WT1-specific CTL line. The genes were inserted into retroviral vectors for transduction of human peripheral blood T lymphocytes of leukemia patients and normal donors. The treatment of leukemia-bearing NOD/SCID mice with T cells transduced with the WT1-specific TCR eliminated leukemia cells in the bone marrow of most mice, while treatment with T cells transduced with a TCR of irrelevant specificity did not diminish the leukemia burden. In order to improve the safety and efficacy of TCR gene therapy, we have developed lentiviral TCR gene transfer. In addition, we employed strategies to enhance TCR expression while avoiding TCR mis-pairing. It may be possible to generate dominant TCR constructs that can suppress the expression of the endogenous TCR on the surface of transduced T cells. The development of new TCR gene constructs holds great promise for the safe and effective delivery of TCR gene therapy for the treatment of malignancies. PMID:17855129

  4. Dendritic cells drive memory CD8 T-cell homeostasis via IL-15 transpresentation

    PubMed Central

    Stonier, Spencer W.; Ma, Lisa J.; Castillo, Eliseo F.

    2008-01-01

    Interleukin-15 (IL-15) is crucial for the development of naive and memory CD8 T cells and is delivered through a mechanism called transpresentation. Previous studies showed that memory CD8 T cells require IL-15 transpresentation by an as yet unknown cell of hematopoietic origin. We hypothesized that dendritic cells (DCs) transpresent IL-15 to CD8 T cells, and we examined this by developing a transgenic model that limits IL-15 transpresentation to DCs. In this study, IL-15 transpresentation by DCs had little effect on restoring naive CD8 T cells but contributed to the development of memory-phenotype CD8 T cells. The generation of virus-specific, memory CD8 T cells was partially supported by IL-15Rα+ DCs through the preferential enhancement of a subset of KLRG-1+CD27− CD8 T cells. In contrast, these DCs were largely sufficient in driving normal homeostatic proliferation of established memory CD8 T cells, suggesting that memory CD8 T cells grow more dependent on IL-15 transpresentation by DCs. Overall, our study clearly supports a role for DCs in memory CD8 T-cell homeostasis but also provides evidence that other hematopoietic cells are involved in this function. The identification of DCs fulfilling this role will enable future studies to better focus on mechanisms regulating T-cell homeostasis. PMID:18812469

  5. 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...

  6. Regulatory T cells prevent CD8 T cell maturation by inhibiting CD4 Th cells at tumor sites.

    PubMed

    Chaput, Nathalie; Darrasse-Jèze, Guillaume; Bergot, Anne-Sophie; Cordier, Corinne; Ngo-Abdalla, Stacie; Klatzmann, David; Azogui, Orly

    2007-10-15

    Natural regulatory T cells (Tregs) are present in high frequencies among tumor-infiltrating lymphocytes and in draining lymph nodes, supposedly facilitating tumor development. To investigate their role in controlling local immune responses, we analyzed intratumoral T cell accumulation and function in the presence or absence of Tregs. Tumors that grew in normal BALB/c mice injected with the 4T1 tumor cell line were highly infiltrated by Tregs, CD4 and CD8 cells, all having unique characteristics. Most infiltrating Tregs expressed low levels of CD25Rs and Foxp3. They did not proliferate even in the presence of IL-2 but maintained a strong suppressor activity. CD4 T cells were profoundly anergic and CD8 T cell proliferation and cytotoxicity were severely impaired. Depletion of Tregs modified the characteristics of tumor infiltrates. Tumors were initially invaded by activated CD4(+)CD25(-) T cells, which produced IL-2 and IFN-gamma. This was followed by the recruitment of highly cytotoxic CD8(+) T cells at tumor sites leading to tumor rejection. The beneficial effect of Treg depletion in tumor regression was abrogated when CD4 helper cells were also depleted. These findings indicate that the massive infiltration of tumors by Tregs prevents the development of a successful helper response. The Tregs in our model prevent Th cell activation and subsequent development of efficient CD8 T cell activity required for the control of tumor growth. PMID:17911581

  7. Differentiation of ICOS+ and ICOS- recent thymic emigrant regulatory T cells (RTE T regs) during normal pregnancy, pre-eclampsia and HELLP syndrome.

    PubMed

    Wagner, M I; Jöst, M; Spratte, J; Schaier, M; Mahnke, K; Meuer, S; Zeier, M; Steinborn, A

    2016-01-01

    Two different subsets of naturally occurring regulatory T cells (nTregs), defined by their expression of the inducible co-stimulatory (ICOS) molecule, are produced by the human thymus. To examine the differentiation of ICOS(+) and ICOS(-) CD45RA(+) CD31(+) recent thymic emigrant (RTE) T regs during normal pregnancy and in the presence of pre-eclampsia or haemolysis elevated liver enzymes low platelet (HELLP)-syndrome, we used six-colour flow cytometric analysis to determine the changes in the composition of the ICOS(+) and ICOS(-) T reg pools with CD45RA(+) CD31(+) RTE T regs, CD45RA(+) CD31(-) mature naive (MN) T regs, CD45RA(-) CD31(+) and CD45RA(-) CD31(-) memory Tregs. With the beginning of pregnancy until term, we observed a strong differentiation of both ICOS(+) and ICOS(-) CD45RA(+) CD31(+) RTE, but not CD45RA(+) CD31(-) MN T regs, into CD45RA(-) CD31(-) memory T regs. At the end of pregnancy, the onset of spontaneous term labour was associated with a significant breakdown of ICOS(+) CD45RA(-) CD31(-) memory T regs. However, in the presence of pre-eclampsia, there was a significantly increased differentiation of ICOS(+) and ICOS(-) CD45RA(+) CD31(+) RTE T regs into CD45RA(-) CD31(+) memory T regs, wherein the lacking differentiation into CD45RA(-) CD31(-) memory T regs was partially replaced by the increased differentiation of ICOS(+) and ICOS(-) CD45RA(+) CD31(-) MN Tregs into CD45RA(-) CD31(-) memory T regs. In patients with HELLP syndrome, this alternatively increased differentiation of CD45RA(-) CD31(-) MN T regs seemed to be exaggerated, and presumably restored the suppressive activity of magnetically isolated ICOS(+) and ICOS(-) T regs, which were shown to be significantly less suppressive in pre-eclampsia patients, but not in HELLP syndrome patients. Hence, our findings propose that the regular differentiation of both ICOS(+) and ICOS(-) CD45RA(+) CD31(+) RTE T regs ensures a healthy pregnancy course, while their disturbed differentiation is

  8. Essential functions for ID proteins at multiple checkpoints in natural killer T cell development

    PubMed Central

    Verykokakis, Mihalis; Krishnamoorthy, Veena; Iavarone, Antonio; Lasorella, Anna; Sigvardsson, Mikael; Kee, Barbara L.

    2013-01-01

    Invariant natural killer T (iNKT) cells display characteristics of both adaptive and innate lymphoid cells (ILCs). Like other ILCs, iNKT cells constitutively express ID proteins, which antagonize the E protein transcription factors that are essential for adaptive lymphocyte development. However, unlike ILCs, ID2 is not essential for thymic iNKT cell development. Here we demonstrated that ID2 and ID3 redundantly promoted iNKT cell lineage specification involving the induction of the signature transcription factor PLZF and that ID3 was critical for development of TBET-dependent NKT1 cells. In contrast, both ID2 and ID3 limited iNKT cell numbers by enforcing the post-selection checkpoint in conventional thymocytes. Therefore, iNKT cells show both adaptive and innate-like requirements for ID proteins at distinct checkpoints during iNKT cell development. PMID:24244015

  9. Stereotaxic administrations of allogeneic human Vγ9Vδ2 T cells efficiently control the development of human glioblastoma brain tumors.

    PubMed

    Jarry, Ulrich; Chauvin, Cynthia; Joalland, Noémie; Léger, Alexandra; Minault, Sandrine; Robard, Myriam; Bonneville, Marc; Oliver, Lisa; Vallette, François M; Vié, Henri; Pecqueur, Claire; Scotet, Emmanuel

    2016-06-01

    Glioblastoma multiforme (GBM) represents the most frequent and deadliest primary brain tumor. Aggressive treatment still fails to eliminate deep brain infiltrative and highly resistant tumor cells. Human Vγ9Vδ2 T cells, the major peripheral blood γδ T cell subset, react against a wide array of tumor cells and represent attractive immune effector T cells for the design of antitumor therapies. This study aims at providing a preclinical rationale for immunotherapies in GBM based on stereotaxic administration of allogeneic human Vγ9Vδ2 T cells. The feasibility and the antitumor efficacy of stereotaxic Vγ9Vδ2 T cell injections have been investigated in orthotopic GBM mice model using selected heterogeneous and invasive primary human GBM cells. Allogeneic human Vγ9Vδ2 T cells survive and patrol for several days within the brain parenchyma following adoptive transfer and can successfully eliminate infiltrative GBM primary cells. These striking observations pave the way for optimized stereotaxic antitumor immunotherapies targeting human allogeneic Vγ9Vδ2 T cells in GBM patients. PMID:27471644

  10. Natural killer T cells are dispensable in the development of allergen-induced airway hyperresponsiveness, inflammation and remodelling in a mouse model of chronic asthma.

    PubMed

    Koh, Y-I; Shim, J-U; Lee, J-H; Chung, I-J; Min, J-J; Rhee, J H; Lee, H C; Chung, D H; Wi, J-O

    2010-07-01

    Natural killer T (NK T) cells have been shown to play an essential role in the development of allergen-induced airway hyperresponsiveness (AHR) and/or airway inflammation in mouse models of acute asthma. Recently, NK T cells have been reported to be required for the development of AHR in a virus induced chronic asthma model. We investigated whether NK T cells were required for the development of allergen-induced AHR, airway inflammation and airway remodelling in a mouse model of chronic asthma. CD1d-/- mice that lack NK T cells were used for the experiments. In the chronic model, AHR, eosinophilic inflammation, remodelling characteristics including mucus metaplasia, subepithelial fibrosis and increased mass of the airway smooth muscle, T helper type 2 (Th2) immune response and immunoglobulin (Ig)E production were equally increased in both CD1d-/- mice and wild-type mice. However, in the acute model, AHR, eosinophilic inflammation, Th2 immune response and IgE production were significantly decreased in the CD1d-/- mice compared to wild-type. CD1d-dependent NK T cells may not be required for the development of allergen-induced AHR, eosinophilic airway inflammation and airway remodelling in chronic asthma model, although they play a role in the development of AHR and eosinophilic inflammation in acute asthma model. PMID:20456411

  11. Repeated systemic administrations of both aminobisphosphonates and human Vγ9Vδ2 T cells efficiently control tumor development in vivo.

    PubMed

    Santolaria, Thibault; Robard, Myriam; Léger, Alexandra; Catros, Véronique; Bonneville, Marc; Scotet, Emmanuel

    2013-08-15

    Peripheral Vγ9Vδ2 T lymphocytes compose a major γδ T cell subset in primates with broad reactivity against tumor cells. Vγ9Vδ2 T cells are specifically activated by phosphorylated isoprenoid pathway metabolites called "phosphoagonists." Accordingly, pharmacologic inhibitors of the mevalonate pathway, such as aminobisphosphonates (NBP) that upregulate the intracellular production of phosphoagonists, increase antitumor Vγ9Vδ2 T cell responses. Immunotherapeutic protocols exploiting GMP-grade agonist molecules targeting human Vγ9Vδ2 T lymphocytes have yielded promising, yet limited, signs of antitumor efficacy and therefore need to be improved for next-generation immunotherapies. In this study, we used a model of s.c. human tumor xenografts in severely immunodeficient mice to assess the antitumor efficacy of systemic NBP treatments when combined with the adoptive transfer of human Vγ9Vδ2 T cells. We show that infusion of Vγ9Vδ2 T cells, 24 h after systemic NBP treatment, efficiently delays tumor growth in mice. Importantly, our results indicate efficient but transient in vivo NBP-induced sensitization of tumor cells to human Vγ9Vδ2-T cell recognition. Accordingly, repeated and combined administrations of both NBP and γδ T cells yielded improved antitumor responses in vivo. Because Vγ9Vδ2 T cells show similar responsiveness toward both autologous and allogeneic tumors and are devoid of alloreactivity, these results provide preclinical proof of concept for optimized antitumor immunotherapies combining NBP treatment and adoptive transfer of allogeneic human γδ T cells. PMID:23836057

  12. 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 TGFβ. 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

  13. T-Cell Lineage Determination

    PubMed Central

    Yang, Qi; Bell, J. Jeremiah; Bhandoola, Avinash

    2010-01-01

    Summary T cells originate from hematopoietic stem cells (HSCs) in the bone marrow but complete their development in the thymus. HSCs give rise to a variety of non-renewing hematopoietic progenitors, among which a rare subset migrates to the thymus via the bloodstream. The earliest T-cell progenitors identified in the thymus are not T-lineage restricted but possess the ability to give rise to cells of many different lineages. Alternative lineage potentials are gradually lost as progenitors progress towards later developmental stages. Here, we review the early developmental events that might be involved in T-cell lineage fate determination, including the properties of possible thymus settling progenitors, their homing into the thymus, and their T-cell lineage specification and commitment. PMID:20969581

  14. Functional profile of S100A4-deficient T cells.

    PubMed

    Weatherly, Kathleen; Bettonville, Marie; Torres, David; Kohler, Arnaud; Goriely, Stanislas; Braun, Michel Y

    2015-12-01

    The protein S100A4 is best known for its significant role in promoting motility and invasive capacity of cancer cells. Since S100A4 expression has been reported also in T cells, we analyzed its potential role in T cell motility and inflammation. Using S100a4(+/Gfp) mice, we show here that S100A4 is exclusively expressed by memory T cells of CD4(+) or CD8(+) subpopulations, predominantly of the effector memory T cell subtype. However, the protein was not required for in vitro memory T cell migration toward gradients of the inflammatory chemokine CXCL10. Moreover, T cell memory response was normal in S100A4-deficient mice and lack of S100a4 gene expression did not induce any defect in promoting the development of protective immunity or inflammatory reactions leading to autoimmunity. Taken together, our results demonstrate that S100A4 activity is dispensable for T cell motility/migration and inflammatory potential. PMID:26734465

  15. An essential role for the transcription factor HEB in thymocyte survival, Tcra rearrangement and the development of natural killer T cells.

    PubMed

    D'Cruz, Louise M; Knell, Jamie; Fujimoto, Jessica K; Goldrath, Ananda W

    2010-03-01

    E proteins are basic helix-loop-helix transcription factors that regulate many key aspects of lymphocyte development. Thymocytes express multiple E proteins that are thought to provide cooperative and compensatory functions crucial for T cell differentiation. Contrary to that, we report here that the E protein HEB was uniquely required at the CD4(+)CD8(+) double-positive (DP) stage of T cell development. Thymocytes lacking HEB showed impaired survival, failed to make rearrangements of variable-alpha (V(alpha)) segments to distal joining-alpha (J(alpha)) segments in the gene encoding the T cell antigen receptor alpha-chain (Tcra) and had a profound, intrinsic block in the development of invariant natural killer T cells (iNKT cells) at their earliest progenitor stage. Thus, our results show that HEB is a specific and essential factor in T cell development and in the generation of the iNKT cell lineage, defining a unique role for HEB in the regulation of lymphocyte maturation. PMID:20154672

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

    PubMed Central

    Dai, Meifang; Zhuang, Yuan

    2014-01-01

    The innate-like T cells expressing Vγ1.1 and Vδ6.3 represent a unique T cell lineage sharing features with both the γδ T and the invariant NKT cells. The population size of Vγ1.1+Vδ6.3+ 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 Vγ1.1+Vδ6.3+ 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 Vγ1.1+Vδ6.3+ T cell expansion. The Vγ1.1+Vδ6.3+ 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 Vγ1.1+Vδ6.3+ 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 γδ T cells. These regulatory effects of Id2 and Id3 on Vγ1.1+Vδ6.3+ T cells are mediated by titration of E protein activity, since removing one or more copies of E protein genes can restore Vγ1.1+Vδ6.3+ 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 γδ lineage through modulating a proper threshold of E-proteins. PMID:24379125

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

    PubMed

    Zhang, Baojun; Lin, Yen-Yu; Dai, Meifang; Zhuang, Yuan

    2014-02-01

    The innate-like T cells expressing Vγ1.1 and Vδ6.3 represent a unique T cell lineage sharing features with both the γδ T and the invariant NKT cells. The population size of Vγ1.1(+)Vδ6.3(+) 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 Vγ1.1(+)Vδ6.3(+) 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 homolog of Id3, to be the major modifier of Id3 in limiting Vγ1.1(+)Vδ6.3(+) T cell expansion. The Vγ1.1(+)Vδ6.3(+) 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 Vγ1.1(+)Vδ6.3(+) T cells because of decreased proliferation and increased cell death. We showed that conditional knockout of Id2 alone is sufficient to promote a moderate expansion of γδ T cells. These regulatory effects of Id2 and Id3 on Vγ1.1(+)Vδ6.3(+) T cells are mediated by titration of E protein activity, because removing one or more copies of E protein genes can restore Vγ1.1(+)Vδ6.3(+) 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 γδ lineage through modulating a proper threshold of E proteins. PMID:24379125

  18. IFNα/βR Signaling Promotes Regulatory T Cell Development and Function Under Stress Conditions

    PubMed Central

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

    2015-01-01

    Type I IFNs are a family of cytokines with antiviral and immunomodulatory properties. While the antiviral effects of IFNs are well characterized, their immunomodulatory properties are less clear. To specifically address the effects of type I IFNs on Treg, we studied mixed bone morrow (BM) chimeras between wild-type (WT) and IFNα/βR (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 Treg had a higher expression of the pro-apoptotic gene Bim and higher frequency of active caspase positive cells. IFNAR KO Treg from chimeric mice displayed a more naïve phenotype, accompanied by lower levels of CD25 and phosphorylated STAT5. Therefore, in Treg IFNAR signaling may directly or indirectly affect phosphorylation of STAT5. In mixed chimeras with Scurfy fetal liver, Treg derived from IFNAR KO BM 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

  19. The cellular immune system in myelomagenesis: NK cells and T cells in the development of MM and their uses in immunotherapies

    PubMed Central

    Dosani, T; Carlsten, M; Maric, I; Landgren, O

    2015-01-01

    As vast strides are being made in the management and treatment of multiple myeloma (MM), recent interests are increasingly focusing on understanding the development of the disease. The knowledge that MM develops exclusively from a protracted phase of monoclonal gammopathy of undetermined significance provides an opportunity to study tumor evolution in this process. Although the immune system has been implicated in the development of MM, the scientific literature on the role and status of various immune components in this process is broad and sometimes contradictory. Accordingly, we present a review of cellular immune subsets in myelomagenesis. We summarize the current literature on the quantitative and functional profiles of natural killer cells and T-cells, including conventional T-cells, natural killer T-cells, γδ T-cells and regulatory T-cells, in myelomagenesis. Our goal is to provide an overview of the status and function of these immune cells in both the peripheral blood and the bone marrow during myelomagenesis. This provides a better understanding of the nature of the immune system in tumor evolution, the knowledge of which is especially significant considering that immunotherapies are increasingly being explored in the treatment of both MM and its precursor conditions. PMID:25885426

  20. Development and characterization of a monoclonal antibody against the putative T cells of Labeo rohita.

    PubMed

    Rebello, Sanjay C; Rathore, Gaurav; Punia, Peyush; Sood, Neeraj

    2016-05-01

    In this study, we have described the development and characterization of monoclonal antibodies (MAbs) directed against thymocytes of rohu, Labeo rohita. MAbs were obtained by immunizing BALB/c mice with freshly isolated and nylon wool column enriched mononuclear cells of thymus. Positive clones against thymocytes were screened by cellular ELISA. The hybridoma showing strong reactivity with nylon wool enriched mononuclear cells, and non-reactivity with a rohu thymus macrophage cell line and rohu serum was selected and subjected to single cell cloning by limiting dilution. The MAbs secreted by a positive clone were designated as E6 MAb. Western blotting of reduced protein from enriched thymocytes showed that E6 reacted with a 166.2 kDa polypeptide and belongs to the IgG1 subclass. Flow cytometric analysis of gated lymphocytes, revealed that the percentage of E6 positive (E6+) cells in thymus (n = 5, 720.4 ± 79.70 g) was 89.7 %. Similarly, the percentage of E6+ cells in kidney, spleen and blood (n = 5) was 6.71, 1.71 and 1.88 %, respectively. In indirect immunoperoxidase test, E6+ cells appeared to be lymphoid cells with a high nucleus to cytoplasmic ratio and were densely packed in the central region of thymus whereas, a few cells were found to be positive in kidney and spleen sections. E6 MAb also reacted with a small population of lymphocytes in blood smear. This MAb appears to be a suitable marker for T lymphocytes and can be a valuable tool in studying immune response and ontogeny of L. rohita immune system. PMID:25749913

  1. Signal 3 determines tolerance versus full activation of naive CD8 T cells: dissociating proliferation and development of effector function.

    PubMed

    Curtsinger, Julie M; Lins, Debra C; Mescher, Matthew F

    2003-05-01

    Activation of naive CD8 T cells to undergo clonal expansion and develop effector function requires three signals: (a) Ag, (b) costimulation, and (c) IL-12 or adjuvant. The requirement for the third signal to stimulate Ag-dependent proliferation is variable, making the greatest contribution when Ag levels are low. At high Ag levels, extensive proliferation can occur in vitro or in vivo in the absence of a third signal. However, despite having undergone the same number of divisions, cells that expand in the absence of a third signal fail to develop cytolytic effector function. Thus, proliferation and development of cytolytic function can be fully uncoupled. Furthermore, these cells are rendered functionally tolerant in vivo, in that subsequent restimulation with a potent stimulus results in limited clonal expansion, impaired IFN-gamma production, and no cytolytic function. Thus, the presence or absence of the third signal appears to be a critical variable in determining whether stimulation by Ag results in tolerance versus development of effector function and establishment of a responsive memory population. PMID:12732656

  2. Interaction of mature CD3+CD4+ T cells with dendritic cells triggers the development of tertiary lymphoid structures in the thyroid

    PubMed Central

    Marinkovic, Tatjana; Garin, Alexandre; Yokota, Yoshifumi; Fu, Yang-Xin; Ruddle, Nancy H.; Furtado, Glaucia C.; Lira, Sergio A.

    2006-01-01

    Ectopic expression of CC chemokine ligand 21 (CCL21) in the thyroid leads to development of lymphoid structures that resemble those observed in Hashimoto thyroiditis. Deletion of the inhibitor of differentiation 2 (Id2) gene, essential for generation of CD3–CD4+ lymphoid tissue–inducer (LTi) cells and development of secondary lymphoid organs, did not affect formation of tertiary lymphoid structures. Rather, mature CD3+CD4+ T cells were critical for the development of tertiary lymphoid structures. The initial stages of this process involved interaction of CD3+CD4+ T cells with DCs, the appearance of peripheral-node addressin–positive (PNAd+) vessels, and production of chemokines that recruit lymphocytes and DCs. These findings indicate that the formation of tertiary lymphoid structures does not require Id2-dependent conventional LTis but depends on a program initiated by mature CD3+CD4+ T cells. PMID:16998590

  3. T Cells Going Innate.

    PubMed

    Seyda, Midas; Elkhal, Abdallah; Quante, Markus; Falk, Christine S; Tullius, Stefan G

    2016-08-01

    Natural killer (NK) cell receptors (NKRs) play a crucial role in the homeostasis of antigen-experienced T cells. Indeed, prolonged antigen stimulation may induce changes in the receptor repertoire of T cells to a profile that features NKRs. Chronic antigen exposure, at the same time, has been shown to trigger the loss of costimulatory CD28 molecules with recently reported intensified antigen thresholds of antigen-experienced CD8(+) T cells. In transplantation, NKRs have been shown to assist allograft rejection in a CD28-independent fashion. We discuss here a role for CD28-negative T cells that have acquired the competency of the NKR machinery, potentially promoting allorecognition either through T cell receptor (TCR) crossreactivity or independently from TCR recognition. Collectively, NKRs can bring about innate-like T cells by providing alternative costimulatory pathways that gain relevance in chronic inflammation, potentially leading to resistance to CD28-targeting immunosuppressants. PMID:27402226

  4. 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

  5. T-cell homeostasis: implications in HIV infection .

    PubMed

    Adleman, L M; Wofsy, D

    1993-02-01

    Evidence is presented that a homeostatic mechanism exists that maintains a normal T-cell count, but is unresponsive to abnormalities in CD4+ T-cell count and CD8+ T-cell count. Specifically, we hypothesize that in all cases of T-cell loss, whether selective or not, both CD4+ T cells and CD8+ T cells will be produced until the absolute T-cell count returns to normal, even if this produces or exacerbates abnormalities in the absolute CD4+ T-cell count and absolute CD8+ T-cell count. This hypothesis implies that the selective loss of CD4+ T cells will induce the production of both CD4+ T cells and CD8+ T cells with the result that T-cell count will return to normal, but a persistent CD8+ T-cell lymphocytosis and CD4+ T-cell lymphopenia will be produced. To test this hypothesis, we monitored T-cell reconstitution in mice selectively depleted of CD4+ T cells through treatment with a CD4-specific monoclonal antibody (mAb). Consistent with our hypothesis, the absolute peripheral blood T-cell count in treated mice returned to that of controls after approximately 4 months. However, the absolute CD8+ cell count became 163% of controls and the absolute CD4+ cell count remained less than 63% of controls. Our hypothesis may have implications regarding the pathogenesis and treatment of human immunodeficiency virus (HIV) infection. In particular, the hypothesis implies that the unresolved CD4+ T-cell lymphopenia seen in the first several years of HIV infection is the "natural" consequence of the interaction of a selective CD4+ T-cell depleting virus and a nonselective T-cell replacing homeostatic mechanism.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8094457

  6. 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-γ 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

  7. Development of a Cell Marker ELISA for the Detection of Goose T Cell Surface CD8α Molecules.

    PubMed

    Cheng, Beibei; Zhang, Wei; Chen, Shun; Wang, Mingshu; Jia, Renyong; Zhu, Dekang; Liu, Mafeng; Sun, Kunfeng; Yang, Qiao; Wu, Ying; Chen, Xiaoyue; Cheng, Anchun

    2016-06-01

    CD8 molecule is a key marker on T cell surface and is connected with the antigen recognition and activation of T lymphocytes. In order to provide a detection method for quantifying goose CD8α expression, this study raised the protein and antibody for goose CD8α and developed a feasible cell marker enzyme-linked immunoabsorbent assay (ELISA) method. Recombinant protein of the extracellular region gene of goCD8α was expressed in prokaryotic expression system, and specific polyclonal antibodies for goCD8α were raised and purified, which was further confirmed by Western-blot, immunofluorescence assay (IFA), and immunohistochemistry (IHC). A cell marker ELISA was established and optimized to detect the change of goCD8α expression between goose parvovirus (GPV)-infected and mock-infected goose peripheral blood mononuclear cells (PBMCs), which is consistent with our previously results of real-time quantitative PCR (qPCR). Cell marker ELISA can provide a new method to detect goCD8α in protein level and in a sensitive, specific, and simple way. This may provide a convenient and novel method for the detection of goCD8α expression. PMID:26879976

  8. Development and characterization of a three-dimensional co-culture model of tumor T cell infiltration.

    PubMed

    Alonso-Nocelo, M; Abuín, C; López-López, R; de la Fuente, M

    2016-01-01

    Tumor growth and metastasis entangle the alteration and recruitment of non-malignant cells to the primary tumor, among them immune cells, constituting the tumor microenvironment (TME). Communication between tumor cells and their stroma has been shown as a fundamental driving force of the tumoral process. A great deal of effort has been focused on depicting their specific interactions and crosstalk. However, most research has been carried out in 2D conventional cultures that alter cell morphology and intracellular signaling processes. Considering these premises, we have developed a 3D cell co-culture model to mimic T cell infiltration into the tumor mass and explore tumor-immune cells interactions in the TME. Expression of specific cell markers and assessment of cell proliferation were carried out to characterize the proposed 3D co-culture model. Additionally, the study and profiling of the secretome revealed a subset of particular cancer-related inflammation proteins prompted upon 3D cultivation of tumor cells in presence of lymphocytes, pointing out an intercellular communication. Altogether, these results suggest that our 3D cell co-culture model can be a useful tool to identify and study critical factors mediating the crosstalk between tumor and immune cells in the TME. Finally, the potential of this model as a drug-screening platform has been explored using docetaxel as a model antitumoral compound. PMID:27078888

  9. Dynamics of T cell responses after stroke.

    PubMed

    Gill, Dipender; Veltkamp, Roland

    2016-02-01

    T cells are integral to the pathophysiology of stroke. The initial inflammatory cascade leads to T cell migration, which results in deleterious and protective effects mediated through CD4(+), CD(8)+, γδ T cells and regulatory T cells, respectively. Cytokines are central to the T cell responses, with key roles established for TNF-α, IFN-γ, IL-17, IL-21 and IL-10. Through communication with the systemic immune system via neural and hormonal pathways, there is also transient immunosuppression after severe strokes. With time, the inflammatory process eventually transforms to one more conducive of repair and recovery, though some evidence also suggests ongoing chronic inflammation. The role of antigen-specific T cell responses requires further investigation. As our understanding develops, there is increasing scope to modulate the T cell response after stroke. PMID:26452204

  10. Improving therapy of chronic lymphocytic leukemia with chimeric antigen receptor T cells.

    PubMed

    Fraietta, Joseph A; Schwab, Robert D; Maus, Marcela V

    2016-04-01

    Adoptive cell immunotherapy for the treatment of chronic lymphocytic leukemia (CLL) has heralded a new era of synthetic biology. The infusion of genetically engineered, autologous chimeric antigen receptor (CAR) T cells directed against CD19 expressed by normal and malignant B cells represents a novel approach to cancer therapy. The results of recent clinical trials of CAR T cells in relapsed and refractory CLL have demonstrated long-term disease-free remissions, underscoring the power of harnessing and redirecting the immune system against cancer. This review will briefly summarize T-cell therapies in development for CLL disease. We discuss the role of T-cell function and phenotype, T-cell culture optimization, CAR design, and approaches to potentiate the survival and anti-tumor effects of infused lymphocytes. Future efforts will focus on improving the efficacy of CAR T cells for the treatment of CLL and incorporating adoptive cell immunotherapy into standard medical management of CLL. PMID:27040708

  11. Enterococcus durans TN-3 Induces Regulatory T Cells and Suppresses the Development of Dextran Sulfate Sodium (DSS)-Induced Experimental Colitis

    PubMed Central

    Kanda, Toshihiro; Ohno, Masashi; Imaeda, Hirotsugu; Shimada, Takashi; Inatomi, Osamu; Bamba, Shigeki; Sugimoto, Mitsushige; Andoh, Akira

    2016-01-01

    Background and Aims Probiotic properties of Enterococcus strains have been reported previously. In this study, we investigated the effects of Enterococcus (E.) durans TN-3 on the development of dextran sulfate sodium (DSS) colitis. Methods BALB/c mice were fed with 4.0% DSS in normal chow. Administration of TN-3 (10mg/day) was initiated 7days before the start of DSS feeding. Mucosal cytokine expression was analyzed by real time-PCR and immunohistochemistry. The lymphocyte subpopulation were analyzed by flow cytometry. The gut microbiota profile was analyzed by a terminal-restriction fragment length polymorphism method (T-RFLP). Results The disease activity index and histological colitis score were significantly lower in the DSS plus TN-3 group than in the DSS group. The mucosal mRNA expression of proinflammatory cytokines (IL-1β, IL-6, IL-17A and IFN-γ) decreased significantly in the DSS plus TN-3 group as compared to the DSS group. The proportion of regulatory T cells (Treg cells) in the mucosa increased significantly in the DSS plus TN-3 group as compared to the DSS group. Both fecal butyrate levels and the diversity of fecal microbial community were significantly higher in the TN-3 plus DSS group than in the DSS group. Conclusions E. durans TN-3 exerted an inhibitory effect on the development of DSS colitis. This action might be mediated by the induction of Treg cells and the restoration of the diversity of the gut microbiota. PMID:27438072

  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. 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

  14. Multilayered specification of the T-cell lineage fate

    PubMed Central

    Rothenberg, Ellen V.; Zhang, Jingli; Li, Long

    2010-01-01

    Summary T-cell development from stem cells has provided a highly accessible and detailed view of the regulatory processes that can go into the choice of a cell fate in a postembryonic, stem cell-based system. But, it has been a view from the outside. The problems in understanding the regulatory basis for this lineage choice begin with the fact that too many transcription factors are needed to provide crucial input: without any one of them, T-cell development fails. Furthermore, almost all the factors known to provide crucial functions during the climax of T-lineage commitment itself are also vital for earlier functions that establish the pool of multilineage precursors that would normally feed into the T-cell specification process. When the regulatory genes that encode them are mutated, the confounding effects on earlier stages make it difficult to dissect T-cell specification genetically. Yet both the positive and the negative regulatory events involved in the choice of a T-cell fate are actually a mosaic of distinct functions. New evidence has emerged recently that finally provides a way to separate the major components that fit together to drive this process. Here, we review insights into T-cell specification and commitment that emerge from a combination of molecular, cellular, and systems biology approaches. The results reveal the regulatory structure underlying this lineage decision. PMID:20969591

  15. Natural T cell immunity against cancer.

    PubMed

    Nagorsen, Dirk; Scheibenbogen, Carmen; Marincola, Francesco M; Letsch, Anne; Keilholz, Ulrich

    2003-10-01

    It has long been a matter of debate whether tumors are spontaneously immunogenic in patients. With the availability of sensitive methods, naturally occurring T cells directed against tumor-associated antigens (TAAs) can be frequently detected in cancer patients. In this review, we summarize the current data on T cell responses to TAAs in various malignancies, including melanoma, colorectal cancer, leukemia, and breast cancer. T cell responses against various antigens, including melanoma differentiation antigens, carcinoembryonic antigen, epithelial cell adhesion molecule, her-2/neu, Wilms' tumor protein, proteinase 3, NY-ESO-1, and surviving, have been reported in a substantial number of patients. In contrast, other TAAs, including most antigens of the MAGE family, do not usually elicit spontaneous T cell responses. A distinction between direct ex vivo T cell responses and in vitro-generated T cell responses is provided because in vitro stimulation results in quantitative and functional changes of T cell responses. The possible role of TAA-specific T cells in immunosurveillance and tumor escape and the implications for immunological treatment strategies are discussed. Naturally occurring T cells against TAAs are a common phenomenon in tumor patients. Understanding the mechanisms and behavior of natural TAA-specific T cells could provide crucial information for rational development of more efficient T cell-directed immunotherapy. PMID:14555498

  16. T cells expressing the V beta 1 T-cell receptor are required for IgA production in the chicken.

    PubMed Central

    Cihak, J; Hoffmann-Fezer, G; Ziegler-Heibrock, H W; Stein, H; Kaspers, B; Chen, C H; Cooper, M D; Lösch, U

    1991-01-01

    While alpha beta T cells in mammals may express one of many variable (V) gene families in the beta locus, chickens have only two V beta gene families. The avian V beta 2+ T cells are recognized by the T-cell receptor 3 (TCR3) monoclonal antibody and V beta 1+ T cells are recognized by the TCR2 antibody, which we used to selectively suppress development of V beta 1+ T cells in order to examine their functional role. Suppression was accomplished by multiple injections of anti-TCR2 antibodies beginning in embryonic life and perpetuated by thymectomy 8 days after hatching. Young birds thus depleted of V beta 1+ T cells had greater than normal numbers of V beta 2+ T cells and appeared as healthy as thymectomized and untreated controls. While production of IgM and IgG antibodies was unimpaired, IgA antibody production was severely compromised in the V beta 1-depleted birds. The levels of secretory IgA in bile and lung lavage fluid were reduced 1000- to 10,000-fold and secretory IgA antibodies were not produced in response to mucosal immunization. B-cell production of IgA antibodies thus appears to require T cells expressing the V beta 1 genes, whereas T cells that express the V beta 2 genes lack this capacity. Images PMID:1835793

  17. Kinetics of Alloantigen-Specific Regulatory CD4 T Cell Development and Tissue Distribution After Donor-Specific Transfusion and Costimulatory Blockade

    PubMed Central

    Tomita, Yusuke; Satomi, Miwa; Baran, William Bracamonte; Gan, Ewa Jankowska; Workman, Andrea Szymczak; Workman, Creg J.; Vignali, Dario Angelo Alberto; Burlingham, William J.

    2016-01-01

    Background The influence of donor-side regulation toward recipient antigens on graft outcome is poorly understood. Methods Because this influence might be due in part to the accumulation of tissue-resident memory T cells in the donor organ, we used a standard murine tolerization model (donor-specific transfusion plus CD40L blockade) to determine the kinetics of development and peripheralization of allospecific regulatory T cell in lymphoid tissues and liver, a secondary lymphoid organ used in transplantation. Results We found that donor-specific transfusion and CD40L blockade leads to a progressive and sustained T regulatory allospecific response. The cytokines IL10, TGFβ, and IL35 all contributed to the regulatory phenomenon as determined by trans vivo delayed hypersensitivity assay. Unexpectedly, an early and transient self-specific regulatory response was found as well. Using double reporter mice (forkhead box p 3 [Foxp3]-yellow fluorescent protein, Epstein-Barr virus-induced gene 3 [Ebi3]-TdTomRed), we found an increase in Foxp3+CD25+ regulatory T (Treg) cells paralleling the regulatory response. The Ebi3+ CD4 T cells (IL35-producing) were mainly classic Treg cells (Foxp3+CD25+), whereas TGFβ+ CD4 T cells are mostly Foxp3-negative, suggesting 2 different CD4 Treg cell subsets. Liver-resident TGFβ+ CD4 T cells appeared more rapidly than Ebi3-producing T cells, whereas at later timepoints, the Ebi3 response predominated both in lymphoid tissues and liver. Conclusions The timing of appearance of donor organ resident Treg cell subsets should be considered in experiments testing the role of bidirectional regulation in transplant tolerance.

  18. HLA-E–restricted regulatory CD8+ T cells are involved in development and control of human autoimmune type 1 diabetes

    PubMed Central

    Jiang, Hong; Canfield, Steve M.; Gallagher, Mary P.; Jiang, Hong H.; Jiang, Yihua; Zheng, Zongyu; Chess, Leonard

    2010-01-01

    A key feature of the immune system is its ability to discriminate self from nonself. Breakdown in any of the mechanisms that maintain unresponsiveness to self (a state known as self-tolerance) contributes to the development of autoimmune conditions. Recent studies in mice show that CD8+ T cells specific for the unconventional MHC class I molecule Qa-1 bound to peptides derived from the signal sequence of Hsp60 (Hsp60sp) contribute to self/nonself discrimination. However, it is unclear whether they exist in humans and play a role in human autoimmune diseases. Here we have shown that CD8+ T cells specific for Hsp60sp bound to HLA-E (the human homolog of Qa-1) exist and play an important role in maintaining peripheral self-tolerance by discriminating self from nonself in humans. Furthermore, in the majority of type 1 diabetes (T1D) patients tested, there was a specific defect in CD8+ T cell recognition of HLA-E/Hsp60sp, which was associated with failure of self/nonself discrimination. However, the defect in the CD8+ T cells from most of the T1D patients tested could be corrected in vitro by exposure to autologous immature DCs loaded with the Hsp60sp peptide. These data suggest that HLA-E–restricted CD8+ T cells may play an important role in keeping self-reactive T cells in check. Thus, correction of this defect could be a potentially effective and safe approach in the therapy of T1D. PMID:20877010

  19. CD4+CD25bright T cells in human intestinal lamina propria as regulatory cells.

    PubMed

    Makita, Shin; Kanai, Takanori; Oshima, Shigeru; Uraushihara, Koji; Totsuka, Teruji; Sawada, Taisuke; Nakamura, Tetsuya; Koganei, Kazutaka; Fukushima, Tsuneo; Watanabe, Mamoru

    2004-09-01

    It is well known that immune responses in the intestine remain in a state of controlled inflammation, suggesting that not only active suppression by regulatory T cells plays an important role in the normal intestinal homeostasis, but also its dysregulation leads to the development of inflammatory bowel disease. In this study, we demonstrate that the CD4(+)CD25(bright) T cells reside in the human intestinal lamina propria (LP) and functionally retain regulatory activities. All human LP CD4(+) T cells regardless of CD25 expression constitutively expressed CTLA-4, glucocorticoid-induced TNFR family-related protein, and Foxp3 and proliferate poorly. Although LP CD4(+)CD25(-) T cells showed an activated and anergic/memory phenotype, they did not retain regulatory activity. In LP CD4(+)CD25(+) T cells, however, cells expressing CD25 at high levels (CD4(+)CD25(bright)) suppressed the proliferation and various cytokine productions of CD4(+)CD25(-) T cells. LP CD4(+)CD25(bright) T cells by themselves produced fewer amounts of IL-2, IFN-gamma, and IL-10. Interestingly, LP CD4(+)CD25(bright) T cells with regulatory T activity were significantly increased in patients with active inflammatory bowel disease. These results suggest that CD4(+)CD25(bright) T cells found in the normal and inflamed intestinal mucosa selectively inhibit the host immune response and therefore may contribute to the intestinal immune homeostasis. PMID:15322172

  20. The Relationship of Development and Normalization.

    ERIC Educational Resources Information Center

    Pieper, Elizabeth J.

    1979-01-01

    The author concludes that, without changing practice to reflect both the philosophical concepts of normalization and the psychological concepts of development, such handicapped people will continue to suffer the traditional trade-offs of normalization at the sacrifice of development, or development at the cost of normalization. (DLS)

  1. Thymic output, T-cell diversity, and T-cell function in long-term human SCID chimeras

    PubMed Central

    Win, Chan M.; Parrott, Roberta E.; Cooney, Myriah; Moser, Barry K.; Roberts, Joseph L.; Sempowski, Gregory D.; Buckley, Rebecca H.

    2009-01-01

    Severe combined immunodeficiency (SCID) is a syndrome of diverse genetic cause characterized by profound deficiencies of T, B, and sometimes NK-cell function. Nonablative human leukocyte antigen–identical or rigorously T cell–depleted haploidentical parental bone marrow transplantation (BMT) results in thymus-dependent genetically donor T-cell development in the recipients, leading to long-term survival. We reported previously that normal T-cell numbers, function, and repertoire developed by 3 to 4 months after transplantation in SCID patients, and the repertoire remained highly diverse for the first 10 years after BMT. The T-cell receptor diversity positively correlated with T-cell receptor excision circle levels, a reflection of thymic output. However, the fate of thymic function in SCID patients beyond 10 to 12 years after BMT remained to be determined. In this greater than 25-year follow-up study of 128 patients with 11 different molecular types of SCID after nonconditioned BMT, we provide evidence that T-cell function, thymic output, and T-cell clonal diversity are maintained long-term. PMID:19433858

  2. Skewed T-cell receptor Vbeta8.2 expression in transgenic CD2-myc induced thymic lymphoma: a role for antigen stimulation in tumour development?

    PubMed Central

    Webster, G.; Onions, D. E.; Neil, J. C.; Cameron, E. R.

    1997-01-01

    Transgenic mice expressing the c-myc proto-oncogene under the control of the CD2-dominant control region show stochastic development of mainly clonal thymic lymphoma with long latency, indicating that cooperative events are needed for the development of the fully malignant phenotype. Previous studies have suggested that T-cell receptor-associated signals can contribute to tumour development. We have therefore used this transgenic model of T-cell transformation to determine whether antigen-specific responses could constitute an epigenetic event in lymphomagenesis. The T-cell receptor (TcR) repertoires of lymphoma clones were analysed with a panel of monoclonal antibodies (Abs) recognizing TcR Vbeta chains. The Vbeta repertoire of tumour clones arising in these mice was non-random with overrepresentation of Vbeta8.2 TcR species. The majority of Vbeta8.2+ clones were of a mature CD3+ CD8 single-positive (SP) phenotype. The biased TcR usage, together with a mature cell phenotype is consistent with the hypothesis that TcR-mediated signals cooperate with activated myc during T-cell transformation. Images Figure 1 PMID:9310239

  3. Orientation-specific RAG activity in chromosomal loop domains contributes to Tcrd V(D)J recombination during T cell development.

    PubMed

    Zhao, Lijuan; Frock, Richard L; Du, Zhou; Hu, Jiazhi; Chen, Liang; Krangel, Michael S; Alt, Frederick W

    2016-08-22

    T cell antigen receptor δ (Tcrd) variable region exons are assembled by RAG-initiated V(D)J recombination events in developing γδ thymocytes. Here, we use linear amplification-mediated high-throughput genome-wide translocation sequencing (LAM-HTGTS) to map hundreds of thousands of RAG-initiated Tcrd D segment (Trdd1 and Trdd2) rearrangements in CD4(-)CD8(-) double-negative thymocyte progenitors differentiated in vitro from bone marrow-derived hematopoietic stem cells. We find that Trdd2 joins directly to Trdv, Trdd1, and Trdj segments, whereas Trdd1 joining is ordered with joining to Trdd2, a prerequisite for further rearrangement. We also find frequent, previously unappreciated, Trdd1 and Trdd2 rearrangements that inactivate Tcrd, including sequential rearrangements from V(D)J recombination signal sequence fusions. Moreover, we find dozens of RAG off-target sequences that are generated via RAG tracking both upstream and downstream from the Trdd2 recombination center across the Tcrd loop domain that is bounded by the upstream INT1-2 and downstream TEA elements. Disruption of the upstream INT1-2 boundary of this loop domain allows spreading of RAG on- and off-target activity to the proximal Trdv domain and, correspondingly, shifts the Tcrd V(D)J recombination landscape by leading to predominant V(D)J joining to a proximal Trdv3 pseudogene that lies just upstream of the normal boundary. PMID:27526713

  4. APC Activation Restores Functional CD4+CD25+ Regulatory T Cells in NOD Mice that Can Prevent Diabetes Development

    PubMed Central

    Manirarora, Jean N.; Kosiewicz, Michele M.; Parnell, Sarah A.; Alard, Pascale

    2008-01-01

    Background Defects in APC and regulatory cells are associated with diabetes development in NOD mice. We have shown previously that NOD APC are not effective at stimulating CD4+CD25+ regulatory cell function in vitro. We hypothesize that failure of NOD APC to properly activate CD4+CD25+ regulatory cells in vivo could compromise their ability to control pathogenic cells, and activation of NOD APC could restore this defect, thereby preventing disease. Methodology/Principal Findings To test these hypotheses, we used the well-documented ability of complete Freund's adjuvant (CFA), an APC activator, to prevent disease in NOD mice. Phenotype and function of CD4+CD25+ regulatory cells from untreated and CFA-treated NOD mice were determined by FACS, and in vitro and in vivo assays. APC from these mice were also evaluated for their ability to activate regulatory cells in vitro. We have found that sick NOD CD4+CD25+ cells expressed Foxp3 at the same percentages, but decreased levels per cell, compared to young NOD or non-NOD controls. Treatment with CFA increased Foxp3 expression in NOD cells, and also increased the percentages of CD4+CD25+Foxp3+ cells infiltrating the pancreas compared to untreated NOD mice. Moreover, CD4+CD25+ cells from pancreatic LN of CFA-treated, but not untreated, NOD mice transferred protection from diabetes. Finally, APC isolated from CFA-treated mice increased Foxp3 and granzyme B expression as well as regulatory function by NOD CD4+CD25+ cells in vitro compared to APC from untreated NOD mice. Conclusions/Significance These data suggest that regulatory T cell function and ability to control pathogenic cells can be enhanced in NOD mice by activating NOD APC. PMID:19011680

  5. 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

  6. SOCS3 deletion in T lymphocytes suppresses development of chronic ocular inflammation via upregulation of CTLA-4 and expansion of regulatory T cells.

    PubMed

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

    2013-11-15

    Suppressors of cytokine signaling (SOCS) proteins are negative-feedback regulators of the JAK/STAT pathway, and SOCS3 contributes to host immunity by regulating the intensity and 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 develop severe experimental autoimmune encephalomyelitis. Interestingly, development of the unique IL-17/IFN-γ double-producing (Th17/IFN-γ and Tc17/IFN-γ) subsets that exhibit strong cytotoxic activities and are 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 the CD4 T cell compartment (CD4-SOCS3 knockout [KO]) 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 experimental autoimmune encephalomyelitis in myeloid-specific SOCS3-deleted mice, CD4-SOCS3KO mice were protected from acute and chronic uveitis. Protection from EAU correlated with enhanced expression of CTLA-4 and expansion of IL-10-producing regulatory T cells with augmented suppressive activities. We further show that SOCS3 interacts with CTLA-4 and negatively regulates CTLA-4 levels in T cells, providing a mechanistic explanation for the expansion of regulatory T cells in CD4-SOCS3 during EAU. Contrary to in vitro epigenetic studies, Th17/IFN-γ and Tc17/IFN-γ populations were markedly reduced in CD4-SOCS3KO, suggesting that SOCS3 promotes expansion of the Th17/IFN-γ subset associated with development of severe uveitis. Thus, SOCS3 is a potential therapeutic target in uveitis and other autoinflammatory diseases. PMID:24101549

  7. Binding immunoglobulin protein-treated peripheral blood monocyte-derived dendritic cells are refractory to maturation and induce regulatory T-cell development.

    PubMed

    Corrigall, Valerie M; Vittecoq, Olivier; Panayi, Gabriel S

    2009-10-01

    Binding immunoglobulin protein (BiP) has been shown previously to have immunomodulatory functions. Herein we investigated whether BiP could affect the differentiation of monocytes into dendritic cells (DCs) and thence the development of regulatory T cells. Peripheral blood monocyte-derived DCs were matured with lipopolysaccharide in the presence or absence of BiP. DC development and T-cell changes were monitored by flow cytometry and regulatory T-cell function was measured by uptake of tritiated thymidine. More BiP-treated DCs (DC((BiP))s) expressed amounts of intracellular indoleamine 2,3-dioxygenase (IDO) and cell surface leucocyte immunoglobulin-like receptor subfamily B member 1 (LILRB1), retained CD14 expression but down-regulated expression of human leucocyte antigen (HLA)-DR and CD86, and produced copious amounts of interleukin (IL)-10, when compared with control DCs. T cells co-cultured with DC((BiP))s developed regulatory function with increased surface expression of CD4(+) CD25(hi) CD27(hi) but with no concomitant increase in forkhead box P3 (Foxp3). These T cells also showed significantly higher levels of intracellular cytotoxic T-lymphocyte antigen (CTLA)-4. The latter could be inhibited by the presence of the IDO inhibitor 1 methyl tryptophan. The addition of neutralizing anti-IL-10 antibody or the specific mitogen-activated protein kinase (MAPK) p38 inhibitor SB203580 reversed the inhibition of DC differentiation by BiP. In conclusion, BiP is an immunomodulator able to arrest inflammation through induction of tolerogenic DCs and subsequent generation of T regulatory cells. PMID:19740378

  8. CD4 T cells are required for both development and maintenance of disease in a new mouse model of reversible colitis.

    PubMed

    Brasseit, J; Althaus-Steiner, E; Faderl, M; Dickgreber, N; Saurer, L; Genitsch, V; Dolowschiak, T; Li, H; Finke, D; Hardt, W-D; McCoy, K D; Macpherson, A J; Corazza, N; Noti, M; Mueller, C

    2016-05-01

    Current therapies to treat inflammatory bowel diseases have limited efficacy, significant side effects, and often wane over time. Little is known about the cellular and molecular mechanisms operative in the process of mucosal healing from colitis. To study such events, we developed a new model of reversible colitis in which adoptive transfer of CD4(+)CD45RB(hi) T cells into Helicobacter typhlonius-colonized lymphopenic mice resulted in a rapid onset of colonic inflammation that was reversible through depletion of colitogenic T cells. Remission was associated with an improved clinical and histopathological score, reduced immune cell infiltration to the intestinal mucosa, altered intestinal gene expression profiles, regeneration of the colonic mucus layer, and the restoration of epithelial barrier integrity. Notably, colitogenic T cells were not only critical for induction of colitis but also for maintenance of disease. Depletion of colitogenic T cells resulted in a rapid drop in tumor necrosis factor α (TNFα) levels associated with reduced infiltration of inflammatory immune cells to sites of inflammation. Although neutralization of TNFα prevented the onset of colitis, anti-TNFα treatment of mice with established disease failed to resolve colonic inflammation. Collectively, this new model of reversible colitis provides an important research tool to study the dynamics of mucosal healing in chronic intestinal remitting-relapsing disorders. PMID:26376366

  9. HLA-DR*0401 expression in the NOD mice prevents the development of autoimmune diabetes by multiple alterations in the T-cell compartment.

    PubMed

    Pow Sang, Luis; Surls, Jacqueline; Mendoza, Mirian; Casares, Sofia; Brumeanu, Teodor

    2015-01-01

    Several human HLA alleles have been found associated with type 1 diabetes (T1D), but their precise role is not clearly defined. Herein, we report that a human MHC class II (HLA-DR*0401) allele transgene that has been expressed into NOD (H-2(g7)I-E(null)) mice prone to T1D rendered the mice resistant to the disease. T1D resistance occurred in the context of multi-point T-cell alterations such as: (i) skewed CD4/CD8 T-cell ratio, (ii) decreased size of CD4(+)CD44(high) T memory pool, (iii) aberrant TCR Vβ repertoire, (iv) increased neonatal number of Foxp3(+) and TR-1(+) regulatory cells, and (v) reduced IFN-γ inflammatory response vs. enhanced IL-10 suppressogenic response of T-cells upon polyclonal and antigen-specific stimulation. The T-cells from NOD/DR4 Tg mice were unable to induce or suppress diabetes in NOD/RAG deficient mice. This study describes a multifaceted regulatory function of the HLA-DR*0401 allele strongly associated with the lack of T1D development in NOD mice. PMID:26363521

  10. Contrasting roles for all-trans retinoic acid in TGF-β–mediated induction of Foxp3 and Il10 genes in developing regulatory T cells

    PubMed Central

    Maynard, Craig L.; Hatton, Robin D.; Helms, Whitney S.; Oliver, James R.; Stephensen, Charles B.

    2009-01-01

    Extrathymic induction of regulatory T (T reg) cells is essential to the regulation of effector T cell responses in the periphery. In addition to Foxp3, T reg cell expression of suppressive cytokines, such as IL-10, is essential for peripheral tolerance, particularly in the intestines. TGF-β has been shown to induce expression of Foxp3 as well as IL10 and the vitamin A metabolite; all-trans retinoic acid (RA [at-RA]) has been found to enhance the former. We report that in contrast to its enhancement of TGF-β–mediated Foxp3 induction, at-RA potently inhibits the TGF-β–mediated induction of Il10 in naive CD4 T cells. Thus, mucosal DC subsets that are active producers of at-RA inhibit induction of Il10 in naive CD4 T cells while promoting induction of Foxp3. Accordingly, mice with vitamin A deficiency have increased numbers of IL-10–competent T reg cells. Activation of DCs by certain Toll-like receptors (TLRs), particularly TLR9, suppresses T cell induction of Foxp3 and enables induction of Il10. Collectively, our data indicate that at-RA has reciprocal effects on the induction of Foxp3 and Il10 in developing CD4+ T reg cells and suggest that TLR9-dependent inhibition of at-RA production by antigen-presenting cells might represent one mechanism to promote the development of IL-10–expressing T cells. PMID:19204112

  11. T-Cell Lymphoma

    MedlinePlus

    ... are extremely rare. T-cell lymphomas can be aggressive (fast-growing) or indolent (slow-growing). Lymphomas are ... also be involved. This group of PTCLs is aggressive and requires combination chemotherapy upon diagnosis. For more ...

  12. 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-CD3ζ 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

  13. Asymptomatic memory CD8+ T cells

    PubMed Central

    Khan, Arif Azam; Srivastava, Ruchi; Lopes, Patricia Prado; Wang, Christine; Pham, Thanh T; Cochrane, Justin; Thai, Nhi Thi Uyen; Gutierrez, Lucas; BenMohamed, Lbachir

    2014-01-01

    Generation and maintenance of high quantity and quality memory CD8+ T cells determine the level of protection from viral, bacterial, and parasitic re-infections, and hence constitutes a primary goal for T cell epitope-based human vaccines and immunotherapeutics. Phenotypically and functionally characterizing memory CD8+ T cells that provide protection against herpes simplex virus type 1 and type 2 (HSV-1 and HSV-2) infections, which cause blinding ocular herpes, genital herpes, and oro-facial herpes, is critical for better vaccine design. We have recently categorized 2 new major sub-populations of memory symptomatic and asymptomatic CD8+ T cells based on their phenotype, protective vs. pathogenic function, and anatomical locations. In this report we are discussing a new direction in developing T cell-based human herpes vaccines and immunotherapeutics based on the emerging new concept of “symptomatic and asymptomatic memory CD8+ T cells.” PMID:24499824

  14. Normal adult ramified microglia separated from other central nervous system macrophages by flow cytometric sorting: Phenotypic differences defined and direct ex vivo antigen presentation to myelin basic protein-reactive CD4{sup +} T cells compared

    SciTech Connect

    Ford, A.L.; Goodsall, A.L.; Sedgwick, J.D.

    1995-05-01

    Ramified microglia in the adult central nervous system (CNS) are the principal glial element up-regulating MHC class I and II expression in response to inflammatory events or neuronal damage. A proportion of these cells also express MHC class II constitutively in the normal CNS. The role of microglia as APCs for CD4{sup +} cells extravasating into the CNS remains undefined. In this study, using irradiation bone marrow chimeras in CD45-congenic rats, the phenotype CD45{sup low}CD11b/c{sup +} is shown to identify microglial cells specifically within the CNS. Highly purified populations of microglia and nonmicroglial but CNS-associated macrophages (CD45{sup high}CD11b/c{sup +}) have been obtained directly from the adult CNS, by using flow cytometric sorting. Morphologically, freshly isolated microglia vs other CNS macrophages are quite distinct. Of the two populations recovered from the normal CNS, it is the minority CD45{sup high}CD11 b/c{sup +} transitional macrophage population, and not microglia, that is the effective APC for experimental autoimmune encephalomyelitis-inducing CD4{sup +} myelin basic protein (MBP)-reactive T cells. CD45{sup high}CD11b/c{sup +} CNS macrophages also stimulate MBP-reactive T cells without addition of MBP to culture suggesting presentation of endogenous Ag. This is the first study in which microglia vs other CNS macrophages have been analyzed for APC ability directly from the CNS, with substantial cross-contamination between the two populations eliminated. The heterogeneity of these populations in terms of APC function is clearly demonstrated. Evidence is still lacking that adult CNS microglia have the capacity to interact with and stimulate CD4{sup +} T cells to proliferate or secrete IL-2. 60 refs., 6 figs., 1 tab.

  15. MEKK3 Is Essential for Lymphopenia-Induced T Cell Proliferation and Survival1

    PubMed Central

    Wang, Xiaofang; Chang, Xing; Facchinetti, Valeria; Zhuang, Yuan; Su, Bing

    2010-01-01

    T cell homeostasis is crucial for maintaining an efficient and balanced T cell immunity. The interaction between TCR and self peptide (sp) MHC ligands is known to be the key driving force in this process, and it is believed to be functionally and mechanistically different from that initiated by the antigenic TCR stimulation. Yet, very little is known about the downstream signaling events triggered by this TCR-spMHC interaction and how they differ from those triggered by antigenic TCR stimulation. In this study, we show that T cell conditional ablation of MEKK3, a Ser/Thr kinase in the MAPK cascade, causes a significant reduction in peripheral T cell numbers in the conditional knockout mice, but does not perturb thymic T cell development and maturation. Using an adoptive mixed transfer method, we show that MEKK3-deficient T cells are severely impaired in lymphopenia-induced cell proliferation and survival. Interestingly, the Ag-induced T cell proliferation proceeds normally in the absence of MEKK3. Finally, we found that the activity of ERK1/2, but not p38 MAPK, was attenuated during the lymphopenia-driven response in MEKK3-deficient T cells. Together, these data suggest that MEKK3 may play a crucial selective role for spMHC-mediated T cell homeostasis. PMID:19265138

  16. The BMP Pathway Participates in Human Naive CD4+ T Cell Activation and Homeostasis

    PubMed Central

    Martínez, Víctor G.; Sacedón, Rosa; Hidalgo, Laura; Valencia, Jaris; Fernández-Sevilla, Lidia M.; Hernández-López, Carmen

    2015-01-01

    Bone Morphogenetic Proteins (BMPs) form a group of secreted factors that belongs to the TGF-β superfamily. Among different roles in a number of immune cell types, BMPs are known to regulate T cell development within the thymus, although the role of BMP signaling in human mature T cells remains elusive. In this study, we demonstrate that canonical BMP signaling is necessary during two critical events that regulate the size and function of human naive CD4+ T cell population: activation and homeostasis. Upon stimulation via TCR, naive CD4+ T cells upregulate the expression of BMP ligands triggering canonical BMP signaling in CD25+ cells. Blockade of BMP signaling severely impairs CD4+ T cell proliferation after activation mainly through regulation of IL-2, since the addition of this cytokine recuperates normal T cell expansion after inhibition of BMP signaling. Similarly, activation of canonical BMP pathway is required for both the maintenance of cell survival and the homeostatic proliferation induced by IL-7, a key factor for T cell homeostasis. Moreover, upregulation of two critical receptors for T cell homeostasis, CXCR4 and CCR9, triggered by IL-7 is also abrogated in the absence of BMP signaling. Collectively, we describe important roles of the canonical BMP signaling in human naive CD4+ T cell activation and homeostasis that could be valuable for clinical application. PMID:26110906

  17. E3 Ubiquitin Ligase Cbl-b Regulates Thymic-Derived CD4+CD25+ Regulatory T Cell Development by Targeting Foxp3 for Ubiquitination.

    PubMed

    Zhao, Yixia; Guo, Hui; Qiao, Guilin; Zucker, Mark; Langdon, Wallace Y; Zhang, Jian

    2015-02-15

    CD28 costimulation is essential for the development of thymic-derived CD4(+)CD25(+)Foxp3(+) regulatory T cells ("tTregs"). E3 ubiquitin ligase Cbl-b has been shown to regulate CD28 dependence of T cell activation. In this paper, we report that the loss of Cbl-b partially but significantly rescues the defective development of tTregs in Cd28(-/-) mice. This partial rescue is independent of IL-2. Mechanistically, Cbl-b binds to Foxp3 upon TCR stimulation and, together with Stub1, targets Foxp3 for ubiquitination and subsequently degradation in the proteasome. As Cbl-b self-ubiquitination and proteasomal degradation is impaired in Cd28(-/-) T cells, the defective development of tTregs in Cd28(-/-) mice may in part be due to increased Foxp3 ubiquitination and degradation targeted by Stub1 and Cbl-b. Treating Cd28(-/-) mice with a proteasome inhibitor completely rescues defective tTreg development in these mice. Therefore, Cbl-b, together with Stub1, ubiquitinate Foxp3, and regulate tTreg development. PMID:25560411

  18. Normal Development of Brain Circuits

    PubMed Central

    Tau, Gregory Z; Peterson, Bradley S

    2010-01-01

    Spanning functions from the simplest reflex arc to complex cognitive processes, neural circuits have diverse functional roles. In the cerebral cortex, functional domains such as visual processing, attention, memory, and cognitive control rely on the development of distinct yet interconnected sets of anatomically distributed cortical and subcortical regions. The developmental organization of these circuits is a remarkably complex process that is influenced by genetic predispositions, environmental events, and neuroplastic responses to experiential demand that modulates connectivity and communication among neurons, within individual brain regions and circuits, and across neural pathways. Recent advances in neuroimaging and computational neurobiology, together with traditional investigational approaches such as histological studies and cellular and molecular biology, have been invaluable in improving our understanding of these developmental processes in humans in both health and illness. To contextualize the developmental origins of a wide array of neuropsychiatric illnesses, this review describes the development and maturation of neural circuits from the first synapse through critical periods of vulnerability and opportunity to the emergent capacity for cognitive and behavioral regulation, and finally the dynamic interplay across levels of circuit organization and developmental epochs. PMID:19794405

  19. Persistent Infection Drives the Development of CD8+ T Cells Specific for Late Lytic Infection Antigens in Lymphocryptovirus-Infected Macaques and Epstein-Barr Virus-Infected Humans▿

    PubMed Central

    Orlova, Nina; Wang, Fred; Fogg, Mark H.

    2011-01-01

    We examined the CD8+ T cell repertoire against lytic infection antigens in rhesus macaques persistently infected with the Epstein-Barr virus (EBV)-related lymphocryptovirus (rhLCV). CD8+ T cells specific for late (L) antigens were detected at rates comparable to those for early antigens and were associated with increasing duration of infection. L antigen-specific CD8+ T cells were also readily detected in adult, EBV-positive humans. Thus, viral major histocompatibility complex class I (MHCI) immune evasion genes expressed during lytic LCV infection do not prevent L-specific CD8+ T cell development over time during persistent infection. PMID:21917961

  20. Unbalanced recovery of regulatory and effector T cells after allogeneic stem cell transplantation contributes to chronic GVHD

    PubMed Central

    Alho, Ana C.; Kim, Haesook T.; Chammas, Marie J.; Reynolds, Carol G.; Matos, Tiago R.; Forcade, Edouard; Whangbo, Jennifer; Nikiforow, Sarah; Cutler, Corey S.; Koreth, John; Ho, Vincent T.; Armand, Philippe; Antin, Joseph H.; Alyea, Edwin P.; Lacerda, Joao F.; Soiffer, Robert J.

    2016-01-01

    The development and maintenance of immune tolerance after allogeneic hematopoietic stem cell transplantation (HSCT) requires the balanced reconstitution of donor-derived CD4 regulatory T cells (CD4Tregs) as well as effector CD4 (conventional CD4 T cells [CD4Tcons]) and CD8 T cells. To characterize the complex mechanisms that lead to unbalanced recovery of these distinct T-cell populations, we studied 107 adult patients who received T-replete stem cell grafts after reduced-intensity conditioning. Immune reconstitution of CD4Treg, CD4Tcon, and CD8 T cells was monitored for a 2-year period. CD3 T-cell counts gradually recovered to normal levels during this period but CD8 T cells recovered more rapidly than either CD4Tregs or CD4Tcons. Reconstituting CD4Tregs and CD4Tcons were predominantly central memory (CM) and effector memory (EM) cells and CD8 T cells were predominantly terminal EM cells. Thymic generation of naive CD4Tcon and CD8 T cells was maintained but thymic production of CD4Tregs was markedly decreased with little recovery during the 2-year study. T-cell proliferation was skewed in favor of CM and EM CD4Tcon and CD8 T cells, especially 6 to 12 months after HSCT. Intracellular expression of BCL2 was increased in CD4Tcon and CD8 T cells in the first 3 to 6 months after HSCT. Early recovery of naive and CM fractions within each T-cell population 3 months after transplant was also strongly correlated with the subsequent development of chronic graft-versus-host disease (GVHD). These dynamic imbalances favor the production, expansion, and persistence of effector T cells over CD4Tregs and were associated with the development of chronic GVHD. PMID:26670634

  1. 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

  2. Regulatory T cells in spontaneous autoimmune encephalomyelitis.

    PubMed

    Furtado, G C; Olivares-Villagómez, D; Curotto de Lafaille, M A; Wensky, A K; Latkowski, J A; Lafaille, J J

    2001-08-01

    Spontaneous experimental autoimmune encephalomyelitis (EAE) develops in 100% of mice harboring a monoclonal myelin basic protein (MBP)-specific CD4+ alphabeta T-cell repertoire. Monoclonality of the alphabeta T-cell repertoire can be achieved by crossing MBP-specific T-cell receptor (TCR) transgenic mice with either RAG-/- mice or TCR alpha-/-/TCR beta-/- double knockout mice. Spontaneous EAE can be prevented by a single administration of purified CD4+ splenocytes or thymocytes obtained from wild-type syngeneic mice. The regulatory T cells (T-reg) that protect from spontaneous EAE need not express the CD25 marker, as effective protection can be attained with populations depleted of CD25+ T cells. Although the specificity of the regulatory T cells is important for their generation or regulatory function, T cells that protect from spontaneous EAE can have a diverse TCR alpha and beta chain composition. T-reg cells expand poorly in vivo, and appear to be long lived. Finally, precursors for T-reg are present in fetal liver as well as in the bone marrow of aging mice. We propose that protection of healthy individuals from autoimmune diseases involves several layers of regulation, which consist of CD4+CD25+ regulatory T cells, CD4+CD25- T-reg cells, and anti-TCR T cells, with each layer potentially operating at different stages of T-helper cell-mediated immune responses. PMID:11722629

  3. Developmental Exposure To 2,3,7,8 Tetrachlorodibenzo-p-Dioxin Attenuates Later-Life Notch1-Mediated T Cell Development and Leukemogenesis

    PubMed Central

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

    2015-01-01

    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 (NotchICN-TG). Following exposure of adult NotchICN-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 3μg/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 NotchICN-TG offspring have a peripheral T-cell pool heavily biased toward the CD4 lineage, while TCDD-exposed NotchICN-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

  4. 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 3μg/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

  5. Retroviral Transduction of T Cells and T Cell Precursors.

    PubMed

    Simmons, Amie; Alberola-Ila, José

    2016-01-01

    Transduction of lymphoid progenitors with retroviral or lentiviral vectors is a powerful experimental strategy to tease out the role of a gene or pathway in T cell development via gain-of-function or loss-of-function strategies. Here we discuss different approaches to use this powerful technology, and present some protocols that we use to transduce murine HSCs, thymocytes, and lymphoid cell lines with these viral vectors. PMID:26294401

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

    SciTech Connect

    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{sup ICN-TG}). Following exposure of adult Notch{sup 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 μg/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{sup ICN-TG} offspring have a peripheral T cell pool heavily biased toward the CD4 lineage, while TCDD-exposed Notch{sup 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. - Highlights: • Adult mice exposed to 30 μg/kg TCDD have higher efficiency of CD8 thymocyte generation. • Mice carrying a constitutively active Notch transgene were exposed to 3 μg/kg TCDD throughout development. • Progression of Notch

  7. 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.

  8. Catharanthus roseus Aqueous Extract is Cytotoxic to Jurkat Leukaemic T-cells but Induces the Proliferation of Normal Peripheral Blood Mononuclear Cells

    PubMed Central

    Ahmad, Nor Hazwani; Rahim, Rohanizah Abdul; Mat, Ishak

    2010-01-01

    Research on natural products has been widely used as a strategy to discover new drugs with potential for applications in complementary medicines because they have fewer side effects than conventional drugs. The aim of the present study was to evaluate the in vitro cytotoxic effects of crude aqueous Catharanthus roseus extract on Jurkat cells and normal peripheral blood mononuclear cells (PBMCs). The aqueous extract was standardised to vinblastine by high performance liquid chromatography (HPLC) and was used to determine cytotoxicity by the MTS [3-(4,5-dimethylthiazol-2-yl)-5(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay. DNA fragmentation assay was employed to determine if cell death was due to apoptosis. The results showed that the aqueous extract induced cell death of Jurkat cells at 24, 48 and 72 hours post-treatment in a time- and dose-dependent manner. However, cells treated at 48 and 72 hours produced higher cytotoxic effects with half maximal inhibitory concentration (IC50) values of 2.55 μg/ml and 2.38 μg/ml, respectively. In contrast, the extract induced normal PBMC proliferation, especially after 24 hours treatment with 1000 μg/ml. This result indicates that the C. roseus crude aqueous extract showed differential effects of inhibiting the proliferation of the Jurkat cell line and promoting the growth of PBMCs. These data suggest that the extract may be applicable for modulating the normal and transformed immune cells in leukaemia patients. PMID:24575203

  9. Selectively Reduced Intracellular Proliferation of Salmonella enterica Serovar Typhimurium within APCs Limits Antigen Presentation and Development of a Rapid CD8 T Cell Response1

    PubMed Central

    Albaghdadi, Homam; Robinson, Nirmal; Finlay, Brett; Krishnan, Lakshmi; Sad, Subash

    2014-01-01

    Ag presentation to CD8+ T cells commences immediately after infection, which facilitates their rapid expansion and control of pathogen. This paradigm is not followed during infection with virulent Salmonella enterica serovar Typhimurium (ST), an intracellular bacterium that causes mortality in susceptible C57BL/6J mice within 7 days and a chronic infection in resistant mice (129 × 1SvJ). Infection of mice with OVA-expressing ST results in the development of a CD8+ T cell response that is detectable only after the second week of infection despite the early detectable bacterial burden. The mechanism behind the delayed CD8+ T cell activation was evaluated, and it was found that dendritic cells/macrophages or mice infected with ST-OVA failed to present Ag to OVA-specific CD8+ T cells. Lack of early Ag presentation was not rescued when mice or dendritic cells/macrophages were infected with an attenuated aroA mutant of ST or with mutants having defective Salmonella pathogenicity island I/II genes. Although extracellular ST proliferated extensively, the replication of ST was highly muted once inside macrophages. This muted intracellular proliferation of ST resulted in the generation of poor levels of intracellular Ag and peptide-MHC complex on the surface of dendritic cells. Additional experiments revealed that ST did not actively inhibit Ag presentation, rather it inhibited the uptake of another intracellular pathogen, Listeria monocytogenes, thereby causing inhibition of Ag presentation against L. monocytogenes. Taken together, this study reveals a dichotomy in the proliferation of ST and indicates that selectively reduced intra-cellular proliferation of virulent pathogens may be an important mechanism of immune evasion. PMID:19692639

  10. Influence of the route of infection on development of T-cell receptor beta-chain repertoires of reovirus-specific cytotoxic T lymphocytes.

    PubMed

    Fulton, Jonathan R; Smith, Jeremy; Cunningham, Cynthia; Cuff, Christopher F

    2004-02-01

    It is well established that the route of infection affects the nature of the adaptive immune response. However, little is known about the effects of the route of exposure on development of cytotoxic T-lymphocyte (CTL) responses. Alternative antigen-presenting cell populations, tissue-restricted expression of class I major histocompatibility complex-encoded molecules, and unique T-cell receptor (TCR)-bearing cells in mucosal tissues could influence the selection and expansion of responder T cells. This study addresses the question of whether the route of virus infection affects the selection and expansion of subpopulations of virus-specific CTLs. Mice were infected orally or in the hind footpads with reovirus, and the repertoires of TCR beta-chains expressed on virus-specific CD8(+) T cells in Peyer's patches or lymph nodes and spleens were examined. CD8(+) cells expressing the variable gene segment of the TCR beta-chain 6 (Vbeta6) expanded in the spleens of mice infected by either route and in CTL lines established from the spleens and draining lymphoid tissues. Adoptively transferred Vbeta6(+) CD8(+) T cells from orally or parenterally infected donors expanded in reovirus-infected severe combined immunodeficient recipient mice and mediated cytotoxicity ex vivo. Furthermore, recovered Vbeta6(+) cells were enriched for clones utilizing uniform complementarity-determining region 3 (CDR3) lengths. However, sequencing of CDR3beta regions from Vbeta6(+) CD8(+) cells indicated that Jbeta gene segment usage is significantly more restricted in CTLs from orally infected mice, suggesting that the route of infection affects selection and/or subsequent expansion of virus-specific CTLs. PMID:14722312

  11. 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

  12. How numbers, nature, and immune status of foxp3(+) regulatory T-cells shape the early immunological events in tumor development.

    PubMed

    Darrasse-Jèze, Guillaume; Podsypanina, Katrina

    2013-01-01

    The influence of CD4(+)CD25(+)Foxp3(+) regulatory T-cells (Tregs) on cancer progression has been demonstrated in a large number of preclinical models and confirmed in several types of malignancies. Neoplastic processes trigger an increase of Treg numbers in draining lymph nodes, spleen, blood, and tumors, leading to the suppression of anti-tumor responses. Treg-depletion before or early in tumor development may lead to complete tumor eradication and extends survival of mice and humans. However this strategy is ineffective in established tumors, highlighting the critical role of the early Treg-tumor encounters. In this review, after discussing old and new concepts of immunological tumor tolerance, we focus on the nature (thymus-derived vs. peripherally derived) and status (naïve or activated/memory) of the regulatory T-cells at tumor emergence. The recent discoveries in this field suggest that the activation status of Tregs and effector T-cells (Teffs) at the first encounter with the tumor are essential to shape the fate and speed of the immune response across a variety of tumor models. The relative timing of activation/recruitment of anti-tumor cells vs. tolerogenic cells at tumor emergence appears to be crucial in the identification of tumor cells as friend or foe, which has broad implications for the design of cancer immunotherapies. PMID:24133490

  13. Murine splenic CD4⁺ T cells, induced by innate immune cell interactions and secreted factors, develop antileukemia cytotoxicity.

    PubMed

    Nelles, Megan E; Moreau, Joshua M; Furlonger, Caren L; Berger, Alexandra; Medin, Jeffrey A; Paige, Christopher J

    2014-11-01

    Inciting the cellular arm of adaptive immunity has been the fundamental goal of cancer immunotherapy strategies, specifically focusing on inducing tumor antigen-specific responses by CD8(+) cytotoxic T lymphocytes (CTL). However, there is an emerging appreciation that the cytotoxic function of CD4(+) T cells can be effective in a clinical setting. Harnessing this potential will require an understanding of how such cells arise. In this study, we use an IL12-transduced variant of the 70Z/3 leukemia cell line in a B6D2F1 (BDF1) murine model system to reveal a novel cascade of cells and soluble factors that activate anticancer CD4(+) killer cells. We show that natural killer T cells play a pivotal role by activating dendritic cells in a contact-dependent manner; soluble products of this interaction, including MCP-1, propagate the activation signal, culminating in the development of CD4(+) CTLs that directly mediate an antileukemia response while also orchestrating a multipronged attack by other effector cells. A more complete picture of the conditions that induce such a robust response will allow us to capitalize on CD4(+) T-cell plasticity for maximum therapeutic effect. PMID:25154710

  14. T cell traffic signals

    PubMed Central

    Van Epps, Heather L.

    2005-01-01

    In 1990, Charles Mackay and colleagues combined classical physiology with modern molecular biology to provide the first concrete evidence that naive and memory T cells follow distinct migratory routes out of the bloodstream— a discovery that helped invigorate the field of lymphocyte homing. PMID:16184630

  15. T cell receptor gene deletion circles identify recent thymic emigrants in the peripheral T cell pool

    PubMed Central

    Kong, Fan-kun; Chen, Chen-lo H.; Six, Adrien; Hockett, Richard D.; Cooper, Max D.

    1999-01-01

    Progenitor cells undergo T cell receptor (TCR) gene rearrangements during their intrathymic differentiation to become T cells. Rearrangements of the variable (V), diversity (D), and joining (J) segments of the TCR genes result in deletion of the intervening chromosomal DNA and the formation of circular episomes as a byproduct. Detection of these extrachromosomal excision circles in T cells located in the peripheral lymphoid tissues has been viewed as evidence for the existence of extrathymic T cell generation. Because all of the T cells in chickens apparently are generated in the thymus, we have employed this avian model to determine the fate of the V(D)J deletion circles. In normal animals we identified TCR Vγ-Jγ and Vβ-Dβ deletion circles in the blood, spleen, and intestines, as well as in the thymus. Thymectomy resulted in the gradual loss of these DNA deletion circles in all of the peripheral lymphoid tissues. A quantitative PCR analysis of Vγ1-Jγ1 and Vβ1-Dβ deletion circles in splenic γδ and Vβ1+ αβ T cells indicated that their numbers progressively decline after thymectomy with a half-life of approximately 2 weeks. Although TCR deletion circles therefore cannot be regarded as reliable indicators of in situ V(D)J rearrangement, measuring their levels in peripheral T cell samples can provide a valuable index of newly generated T cells entering the T cell pool. PMID:9990059

  16. Metformin ameliorates the development of experimental autoimmune encephalomyelitis by regulating T helper 17 and regulatory T cells in mice.

    PubMed

    Sun, Yafei; Tian, Tian; Gao, Juan; Liu, Xiaoqian; Hou, Huiqing; Cao, Runjing; Li, Bin; Quan, Moyuan; Guo, Li

    2016-03-15

    Immoderate immunoreaction of antigen-specific Th17 and Treg cell dysfunction play critical roles in the pathogenesis of multiple sclerosis. We examined Th17/Treg immune responses and the underlying mechanisms in response to metformin in C57BL/6 mice with experimental autoimmune encephalomyelitis (EAE). Metformin reduced Th17 and increased Treg cell percentages along with the levels of associated cytokines. Molecules involved in cellular metabolism were altered in mice with EAE. Suppressed activation of mTOR and its downstream target, HIF-1α, likely mediated the protective effects of metformin. Our findings demonstrate that regulation of T cell metabolism represents a new therapeutic target for CNS autoimmune disorders. PMID:26943960

  17. T cell responses in dengue viral infections.

    PubMed

    Malavige, Gathsaurie Neelika; Ogg, Graham S

    2013-12-01

    Dengue viral infections are the commonest mosquito borne viral infection in the world, affecting more than 100 countries and 390 million individuals annually. Currently, there are no effective antiviral drugs or an effective vaccine to prevent infection. A main hurdle in developing a safe and effective vaccine has been our poor understanding of the complex nature of the protective immune response in acute dengue infection and the presence of four dengue virus (DV) serotypes that are highly homologous. The role of DV specific T cells in the pathogenesis of severe clinical disease in not clear. It has been speculated that highly cross reactive T cells for the previous infecting heterologous DV serotype, which produce pro-inflammatory cytokines, contribute to disease pathogenesis. These cross reactive T cells are believed to be suboptimal in clearing the infection with the current DV-serotype. However, other studies have shown that cross-reactive DV-specific T cells are absent or present in very low frequency during acute infection, appearing only during the convalescent period in the majority of patients. Furthermore, significant apoptosis of T cells occurs in severe acute clinical disease. Overall therefore, it is unclear what role T cells play in contributing to disease pathogenesis during acute dengue infection. Existing data have been complicated by cross-reactivity in T cells assays. These findings can now be re-evaluated in the light of novel technologies to identify serotype-specific T cell responses. PMID:24220605

  18. Targeting T cell metabolism for therapy

    PubMed Central

    O’Sullivan, David

    2015-01-01

    In the past several years, a wealth of evidence has emerged illustrating how metabolism supports many aspects of T cell biology, as well as how metabolic changes drive T cell differentiation and fate. Here we outline developing principles in the regulation of T cell metabolism, and discuss how these processes are impacted in settings of inflammation and cancer. In this context we discuss how metabolic pathways might be manipulated for the treatment of human disease, including how metabolism may be targeted to prevent T cell dysfunction in inhospitable microenvironments, to generate more effective adoptive cellular immunotherapies in cancer, and to direct T cell differentiation and function towards non-pathogenic phenotypes in settings of autoimmunity. PMID:25601541

  19. Preselection Thymocytes Are More Sensitive to T Cell Receptor Stimulation Than Mature T Cells

    PubMed Central

    Davey, Gayle M.; Schober, Sonya L.; Endrizzi, Bart T.; Dutcher, Angela K.; Jameson, Stephen C.; Hogquist, Kristin A.

    1998-01-01

    During T cell development, thymocytes which are tolerant to self-peptides but reactive to foreign peptides are selected. The current model for thymocyte selection proposes that self-peptide–major histocompatibility complex (MHC) complexes that bind the T cell receptor with low affinity will promote positive selection while those with high affinity will result in negative selection. Upon thymocyte maturation, such low affinity self-peptide–MHC ligands no longer provoke a response, but foreign peptides can incidentally be high affinity ligands and can therefore stimulate T cells. For this model to work, thymocytes must be more sensitive to ligand than mature T cells. Contrary to this expectation, several groups have shown that thymocytes are less responsive than mature T cells to anti-T cell receptor for antigen (TCR)/CD3 mAb stimulation. Additionally, the lower TCR levels on thymocytes, compared with T cells, would potentially correlate with decreased thymocyte sensitivity. Here we compared preselection thymocytes and mature T cells for early activation events in response to peptide–MHC ligands. Remarkably, the preselection thymocytes were more responsive than mature T cells when stimulated with low affinity peptide variants, while both populations responded equally well to the antigenic peptide. This directly demonstrates the increased sensitivity of thymocytes compared with T cells for TCR engagement by peptide–MHC complexes. PMID:9815264

  20. Apoptosis-Inducing-Factor-Dependent Mitochondrial Function Is Required for T Cell but Not B Cell Function.

    PubMed

    Milasta, Sandra; Dillon, Christopher P; Sturm, Oliver E; Verbist, Katherine C; Brewer, Taylor L; Quarato, Giovanni; Brown, Scott A; Frase, Sharon; Janke, Laura J; Perry, S Scott; Thomas, Paul G; Green, Douglas R

    2016-01-19

    The role of apoptosis inducing factor (AIF) in promoting cell death versus survival remains controversial. We report that the loss of AIF in fibroblasts led to mitochondrial electron transport chain defects and loss of proliferation that could be restored by ectopic expression of the yeast NADH dehydrogenase Ndi1. Aif-deficiency in T cells led to decreased peripheral T cell numbers and defective homeostatic proliferation, but thymic T cell development was unaffected. In contrast, Aif-deficient B cells developed and functioned normally. The difference in the dependency of T cells versus B cells on AIF for function and survival correlated with their metabolic requirements. Ectopic Ndi1 expression rescued homeostatic proliferation of Aif-deficient T cells. Despite its reported roles in cell death, fibroblasts, thymocytes and B cells lacking AIF underwent normal death. These studies suggest that the primary role of AIF relates to complex I function, with differential effects on T and B cells. PMID:26795252

  1. 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-γ-double producing (Th17/IFN-γ and Tc17/IFN-γ) 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-γ and Tc17/IFN-γ populations were markedly reduced in CD4-SOCS3KO, suggesting that SOCS3 promotes expansion of Th17/IFN-γ subset associated with development of severe uveitis. Thus, SOCS3 is a potential therapeutic target in uveitis and other auto-inflammatory diseases. PMID:24101549

  2. [Extranodal natural killer/T-cell lymphoma, nasal type developing central nervous system and epididymis involvement immediately after concurrent chemoradiotherapy].

    PubMed

    Sasaki, Yuya; Yonezawa, Akihito; Kinoshita, Yoshihiro; Kitagawa, Tomoya; Mori, Minako; Onaka, Takashi; Imada, Kazunori

    2015-12-01

    A 66-year-old man showed central nervous system (CNS) and epididymis involvement after concurrent chemoradiotherapy for extranodal natural killer/T-cell lymphoma, nasal type (ENKL). The patient experienced continuous nasal obstruction. CT revealed a mass in the nasal cavity and paranasal sinuses. Biopsy of the nasal cavity mass showed it to be ENKL. Based on bone marrow biopsy and 18F-FDG PET/CT findings, the clinical stage was suspected to be IIE. The sites involved were the nasal cavity, paranasal sinuses, and cervical lymph nodes. We performed concurrent chemoradiotherapy consisting of a 67% dose of DeVIC and involved field radiation therapy towards his head and neck. Head and neck CT confirmed a therapeutic response. After receiving concurrent chemoradiotherapy, the patient complained of perineal discomfort. Ultrasonography revealed swelling of the left epididymis. Left epididymis biopsy showed ENKL involvement and lumbar puncture revealed CNS involvement. The findings of this case suggest that evaluation of CNS involvement might be an essential part of the initial workup for some ENKL patients. PMID:26725358

  3. Role of CD8(+) T-cell immunity in influenza infection: potential use in future vaccine development.

    PubMed

    La Gruta, Nicole; Kelso, Anne; Brown, Lorena E; Chen, Wiesan; Jackson, David C; Turner, Stephen J

    2009-10-01

    Continued circulation of the highly pathogenic avian H5N1 influenza A virus has many people worried that an influenza pandemic is imminent. Compounding this is the realization that H5N1 vaccines based on current influenza vaccine technology (designed to generate protective antibody responses) may be suboptimal at providing protection. As a consequence, there is recent interest in vaccine strategies that elicit cellular immunity, particularly the cytotoxic T lymphocyte response, in an effort to provide protection against a potential pandemic. A major issue is the lack of information about the precise role that these 'hitmen' of the immune system have in protecting against both pandemic and seasonal influenza. We need to know more about how the induction and maintenance of cytotoxic T lymphocytes after influenza infection can impact protection from further infection. The challenge is then to use this information in the design of vaccines that will protect against pandemic influenza and will help optimize CD8(+) killer T-cell responses in other infections. PMID:20477341

  4. Hepatosplenic alphabeta T cell lymphoma.

    PubMed

    Nagai, Yuya; Ikegame, Kazuhiro; Mori, Minako; Inoue, Daichi; Kimura, Takaharu; Shimoji, Sonoko; Togami, Katsuhiro; Tabata, Sumie; Kurata, Masayuki; Imai, Yukihiro; Matsushita, Akiko; Nagai, Kenichi; Ogawa, Hiroyasu; Takahashi, Takayuki

    2010-04-01

    A 32-year-old male with chronic hepatitis B was admitted to a hospital with cellulitis in the right leg in September 2006. Pancytopenia, hepatosplenomegaly, and systemic superficial lymph node swelling were noted, and he was referred to our hospital. He developed fever and liver dysfunction in June 2007 and underwent a splenectomy. His pancytopenia subsequently improved. A pathologic diagnosis of hepatosplenic alphabeta T cell lymphoma was made by examining spleen tissue and biopsy specimens of the liver and mesenteric lymph node. He had stage IVB disease because neoplastic T cells were noted in the bone marrow. The response of the lymphoma to conventional chemotherapy including the CHOP (cyclophosphamide, adriamycin, vincristine, prednisolone) and DeVIC (dexamethasone, etoposide, ifoshamide, carboplatin) regimens was poor and transient. A partial remission was obtained with an ESHAP (etoposide, cisplatin, cytarabine, methylprednisolone) regimen. Therefore, we planned a bone marrow transplantation (BMT) from an HLA-haploidentical sibling donor. He was moved to the Department of Hematology, Hyogo Medical College, to receive this BMT as part of a clinical trial. During the conditioning procedure for the transplantation, however, he died of septicemia. Since hepatosplenic alphabeta T cell lymphoma is very rare with only 23 reported cases to date, herein we report this case and discuss the therapeutic strategy. PMID:20217452

  5. Development and function of invariant natural killer T cells producing T(h)2- and T(h)17-cytokines.

    PubMed

    Watarai, Hiroshi; Sekine-Kondo, Etsuko; Shigeura, Tomokuni; Motomura, Yasutaka; Yasuda, Takuwa; Satoh, Rumi; Yoshida, Hisahiro; Kubo, Masato; Kawamoto, Hiroshi; Koseki, Haruhiko; Taniguchi, Masaru

    2012-02-01

    There is heterogeneity in invariant natural killer T (iNKT) cells based on the expression of CD4 and the IL-17 receptor B (IL-17RB), a receptor for IL-25 which is a key factor in T(H)2 immunity. However, the development pathway and precise function of these iNKT cell subtypes remain unknown. IL-17RB⁺iNKT cells are present in the thymic CD44⁺/⁻ NK1.1⁻ population and develop normally even in the absence of IL-15, which is required for maturation and homeostasis of IL-17RB⁻iNKT cells producing IFN-γ. These results suggest that iNKT cells contain at least two subtypes, IL-17RB⁺ and IL-17RB⁻ subsets. The IL-17RB⁺iNKT subtypes can be further divided into two subtypes on the basis of CD4 expression both in the thymus and in the periphery. CD4⁺ IL-17RB⁺iNKT cells produce T(H)2 (IL-13), T(H)9 (IL-9 and IL-10), and T(H)17 (IL-17A and IL-22) cytokines in response to IL-25 in an E4BP4-dependent fashion, whereas CD4⁻ IL-17RB⁺iNKT cells are a retinoic acid receptor-related orphan receptor (ROR)γt⁺ subset producing T(H)17 cytokines upon stimulation with IL-23 in an E4BP4-independent fashion. These IL-17RB⁺iNKT cell subtypes are abundantly present in the lung in the steady state and mediate the pathogenesis in virus-induced airway hyperreactivity (AHR). In this study we demonstrated that the IL-17RB⁺iNKT cell subsets develop distinct from classical iNKT cell developmental stages in the thymus and play important roles in the pathogenesis of airway diseases. PMID:22346732

  6. Genetically Modified T Cells for the Treatment of Malignant Disease

    PubMed Central

    Wieczorek, Agnieszka; Uharek, Lutz

    2013-01-01

    Summary The broaden application of adoptive T-cell transfer has been constrained by the technical abilities to isolate and expand antigen-specific T cells potent to selectively kill tumor cells. With the recent progress in the design and manufacturing of cellular products, T cells used in the treatment of malignant diseases may be regarded as anticancer biopharmaceuticals. Genetical manipulation of T cells has given T cells desired specificity but also enable to tailor their activation and proliferation potential. Here, we summarize the recent developments in genetic engineering of T-cell-based biopharmaceuticals, covering criteria for their clinical application in regard to safety and efficacy. PMID:24474888

  7. Designer T cells by T cell receptor replacement.

    PubMed

    Sommermeyer, Daniel; Neudorfer, Julia; Weinhold, Monika; Leisegang, Matthias; Engels, Boris; Noessner, Elfriede; Heemskerk, Mirjam H M; Charo, Jehad; Schendel, Dolores J; Blankenstein, Thomas; Bernhard, Helga; Uckert, Wolfgang

    2006-11-01

    T cell receptor (TCR) gene transfer is a convenient method to produce antigen-specific T cells for adoptive therapy. However, the expression of two TCR in T cells could impair their function or cause unwanted effects by mixed TCR heterodimers. With five different TCR and four different T cells, either mouse or human, we show that some TCR are strong--in terms of cell surface expression--and replace weak TCR on the cell surface, resulting in exchange of antigen specificity. Two strong TCR are co-expressed. A mouse TCR replaces human TCR on human T cells. Even though it is still poorly understood why some TCRalpha/beta combinations are preferentially expressed on T cells, our data suggest that, in the future, designer T cells with exclusive tumor reactivity can be generated by T cell engineering. PMID:17051621

  8. TNF-alpha mediated modulation of T cell development and exacerbation of in vitro T1DM in fetal thymus organ culture.

    PubMed

    Middlebrook, Aaron J; Lebsack, Ty; DeLuca, Dominick

    2007-01-01

    TNF-alpha is a pleiotropic cytokine that is constitutively expressed in the thymus. This cytokine has opposing effects on type 1 diabetes mellitus (T1DM) as non-obese diabetic (NOD) mice administered TNF-alpha early in life experience an acceleration in disease onset while TNF-alpha administered to adult NOD mice are rescued from disease entirely. Using fetal thymus organ culture (FTOC) as a model of T cell development and an associated in vitro T1DM model, we set out to reconcile the role of TNF-alpha in thymic development with its role in the pathogenesis of T1DM. Our data indicate that NOD derived FTOC produce a smaller percentage of double negative (CD4(-)/CD8(-)) thymocytes expressing TNF receptors compared to non-diabetic C57BL/6 (B6) derived FTOC. NOD FTOC produce more TNF-alpha than B6 FTOC during days 6-9 of culture, a time when negative selection of T cells is known to occur. Neutralization of this endogenous TNF-alpha production in NOD derived FTOC with soluble TNF receptor (sTNF R1) rescued insulin production in our in vitro T1DM model. Flow cytometric analysis of NOD FTOC treated with recombinant TNF-alpha (rTNF-alpha) or sTNF R1 demonstrated that the relative levels of TNF-alpha in the culture during the selection window (days 6-9) influence the ratio of immature vs. mature T cells that emerge from FTOC. PMID:17716860

  9. Pharmacologic suppression of target cell recognition by engineered T cells expressing chimeric T-cell receptors.

    PubMed

    Alvarez-Vallina, L; Yañez, R; Blanco, B; Gil, M; Russell, S J

    2000-04-01

    Adoptive therapy with autologous T cells expressing chimeric T-cell receptors (chTCRs) is of potential interest for the treatment of malignancy. To limit possible T-cell-mediated damage to normal tissues that weakly express the targeted tumor antigen (Ag), we have tested a strategy for the suppression of target cell recognition by engineered T cells. Jurkat T cells were transduced with an anti-hapten chTCR tinder the control of a tetracycline-suppressible promoter and were shown to respond to Ag-positive (hapten-coated) but not to Ag-negative target cells. The engineered T cells were then reacted with hapten-coated target cells at different effector to target cell ratios before and after exposure to tetracycline. When the engineered T cells were treated with tetracycline, expression of the chTCR was greatly decreased and recognition of the hapten-coated target cells was completely suppressed. Tetracycline-mediated suppression of target cell recognition by engineered T cells may be a useful strategy to limit the toxicity of the approach to cancer gene therapy. PMID:10811469

  10. Improved anti-leukemia activities of adoptively transferred T cells expressing bispecific T-cell engager in mice.

    PubMed

    Liu, X; Barrett, D M; Jiang, S; Fang, C; Kalos, M; Grupp, S A; June, C H; Zhao, Y

    2016-01-01

    Despite the impressive clinical efficacy of T cells engineered to express chimeric antigen receptors (CAR-Ts), the current applications of CAR-T cell therapy are limited by major treatment-related toxicity. Thus, safer yet effective alternative approaches must be developed. In this study, we compared CD19 bispecific T-cell engager (BiTE)-transferred T cells that had been transfected by RNA electroporation with CD19 CAR RNA-transferred T cells both in vitro and in an aggressive Nalm6 leukemia mouse model. BiTEs were secreted from the transferred T cells and enabled both the transferred and bystander T cells to specifically recognize CD19(+) cell lines, with increased tumor killing ability, prolonged functional persistence, increased cytokine production and potent proliferation compared with the CAR-T cells. More interestingly, in comparison with CD3/CD28 bead-stimulated T cells, T cells that were expanded by a rapid T-cell expansion protocol (REP) showed enhanced anti-tumor activities for both CAR and BiTE RNA-electroporated T cells both in vitro and in a Nalm6 mouse model (P<0.01). Furthermore, the REP T cells with BiTE RNAs showed greater efficacy in the Nalm6 leukemia model compared with REP T cells with CAR RNA (P<0.05) and resulted in complete leukemia remission. PMID:27258611

  11. Regulatory T Cells in Radiotherapeutic Responses

    PubMed Central

    Schaue, Dörthe; Xie, Michael W.; Ratikan, Josephine A.; McBride, William H.

    2012-01-01

    Radiation therapy (RT) can extend its influence in cancer therapy beyond what can be attributed to in-field cytotoxicity by modulating the immune system. While complex, these systemic effects can help tip the therapeutic balance in favor of treatment success or failure. Engagement of the immune system is generally through recognition of damage-associated molecules expressed or released as a result of tumor and normal tissue radiation damage. This system has evolved to discriminate pathological from physiological forms of cell death by signaling “danger.” The multiple mechanisms that can be evoked include a shift toward a pro-inflammatory, pro-oxidant microenvironment that can promote maturation of dendritic cells and, in cancer treatment, the development of effector T cell responses to tumor-associated antigens. Control over these processes is exerted by regulatory T cells (Tregs), suppressor macrophages, and immunosuppressive cytokines that act in consort to maintain tolerance to self, limit tissue damage, and re-establish tissue homeostasis. Unfortunately, by the time RT for cancer is initiated the tumor-host relationship has already been sculpted in favor of tumor growth and against immune-mediated mechanisms for tumor regression. Reversing this situation is a major challenge. However, recent data show that removal of Tregs can tip the balance in favor of the generation of radiation-induced anti-tumor immunity. The clinical challenge is to do so without excessive depletion that might precipitate serious autoimmune reactions and increase the likelihood of normal tissue complications. The selective modulation of Treg biology to maintain immune tolerance and control of normal tissue damage, while releasing the “brakes” on anti-tumor immune responses, is a worthy aim with promise for enhancing the therapeutic benefit of RT for cancer. PMID:22912933

  12. 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

  13. How some T cells escape tolerance induction.

    PubMed

    Gammon, G; Sercarz, E

    1989-11-01

    A feature common to many animal models of autoimmune disease, for example, experimental allergic encephalomyelitis, experimental autoimmune myasthenia gravis and collagen-induced arthritis, is the presence of self-reactive T cells in healthy animals, which are activated to produce disease by immunization with exogenous antigen. It is unclear why these T cells are not deleted during ontogeny in the thymus and, having escaped tolerance induction, why they are not spontaneously activated by self-antigen. To investigate these questions, we have examined an experimental model in which mice are tolerant to an antigen despite the presence of antigen-reactive T cells. We find that the T cells that escape tolerance induction are specific for minor determinants on the antigen. We propose that these T cells evade tolerance induction because some minor determinants are only available in relatively low amounts after in vivo processing of the whole antigen. For the same reason, these T cells are not normally activated but can be stimulated under special circumstances to circumvent tolerance. PMID:2478888

  14. Modulation of CD4+ T Cell-Dependent Specific Cytotoxic CD8+ T Cells Differentiation and Proliferation by the Timing of Increase in the Pathogen Load

    PubMed Central

    Tzelepis, Fanny; Persechini, Pedro M.; Rodrigues, Mauricio M.

    2007-01-01

    Background Following infection with viruses, bacteria or protozoan parasites, naïve antigen-specific CD8+ T cells undergo a process of differentiation and proliferation to generate effector cells. Recent evidences suggest that the timing of generation of specific effector CD8+ T cells varies widely according to different pathogens. We hypothesized that the timing of increase in the pathogen load could be a critical parameter governing this process. Methodology/Principal Findings Using increasing doses of the protozoan parasite Trypanosoma cruzi to infect C57BL/6 mice, we observed a significant acceleration in the timing of parasitemia without an increase in mouse susceptibility. In contrast, in CD8 deficient mice, we observed an inverse relationship between the parasite inoculum and the timing of death. These results suggest that in normal mice CD8+ T cells became protective earlier, following the accelerated development of parasitemia. The evaluation of specific cytotoxic responses in vivo to three distinct epitopes revealed that increasing the parasite inoculum hastened the expansion of specific CD8+ cytotoxic T cells following infection. The differentiation and expansion of T. cruzi-specific CD8+ cytotoxic T cells is in fact dependent on parasite multiplication, as radiation-attenuated parasites were unable to activate these cells. We also observed that, in contrast to most pathogens, the activation process of T. cruzi-specific CD8+ cytotoxic T cells was dependent on MHC class II restricted CD4+ T cells. Conclusions/Significance Our results are compatible with our initial hypothesis that the timing of increase in the pathogen load can be a critical parameter governing the kinetics of CD4+ T cell-dependent expansion of pathogen-specific CD8+ cytotoxic T cells. PMID:17460760

  15. T Cell factor 1 represses CD8+ effector T cell formation and function.

    PubMed

    Tiemessen, Machteld M; Baert, Miranda R M; Kok, Lianne; van Eggermond, Marja C J A; van den Elsen, Peter J; Arens, Ramon; Staal, Frank J T

    2014-12-01

    The Wnt-responsive transcription factor T cell factor 1 (Tcf1) is well known for its role in thymic T cell development and the formation of memory CD8(+) T cells. However, its role in the initial phases of CD8(+) T effector cell formation has remained unexplored. We report that high levels of Wnt signaling and Tcf1 are operational in naive and memory CD8(+) T cells, whereas Wnt signaling and Tcf1 were low in effector CD8(+) T cells. CD8(+) T cells deficient in Tcf1 produce IFN-γ more rapidly, coinciding with increased demethylation of the IFN-γ enhancer and higher expression of the transcription factors Tbet and Blimp1. Moreover, virus-specific Tcf1(-/-) CD8(+) T cells show accelerated expansion in acute infection, which is associated with increased IFN-γ and TNF production and lower viral load. Genetic complementation experiments with various Tcf1 isoforms indicate that Tcf1 dosage and protein stability are critical in suppressing IFN-γ production. Isoforms lacking the β-catenin binding domain are equally effective in inhibiting CD8(+) effector T cell formation. Thus, Tcf1 functions as a repressor of CD8(+) effector T cell formation in a β-catenin/Wnt-independent manner. PMID:25355919

  16. Caveolin-1 regulates TCR signal strength and regulatory T-cell differentiation into alloreactive T cells.

    PubMed

    Schönle, Anne; Hartl, Frederike A; Mentzel, Jan; Nöltner, Theresa; Rauch, Katharina S; Prestipino, Alessandro; Wohlfeil, Sebastian A; Apostolova, Petya; Hechinger, Anne-Kathrin; Melchinger, Wolfgang; Fehrenbach, Kerstin; Guadamillas, Marta C; Follo, Marie; Prinz, Gabriele; Ruess, Ann-Katrin; Pfeifer, Dietmar; Angel Del Pozo, Miguel; Schmitt-Graeff, Annette; Duyster, Justus; Hippen, Keli I; Blazar, Bruce R; Schachtrup, Kristina; Minguet, Susana; Zeiser, Robert

    2016-04-14

    Caveolin-1 (Cav-1) is a key organizer of membrane specializations and a scaffold protein that regulates signaling in multiple cell types. We found increased Cav-1 expression in human and murine T cells after allogeneic hematopoietic cell transplantation. Indeed, Cav-1(-/-)donor T cells caused less severe acute graft-versus-host disease (GVHD) and yielded higher numbers of regulatory T cells (Tregs) compared with controls. Depletion of Tregs from the graft abrogated this protective effect. Correspondingly, Treg frequencies increased when Cav-1(-/-)T cells were exposed to transforming growth factor-β/T-cell receptor (TCR)/CD28 activation or alloantigen stimulation in vitro compared with wild-type T cells. Mechanistically, we found that the phosphorylation of Cav-1 is dispensable for the control of T-cell fate by using a nonphosphorylatable Cav-1 (Y14F/Y14F) point-mutation variant. Moreover, the close proximity of lymphocyte-specific protein tyrosine kinase (Lck) to the TCR induced by TCR-activation was reduced in Cav-1(-/-)T cells. Therefore, less TCR/Lck clustering results in suboptimal activation of the downstream signaling events, which correlates with the preferential development into a Treg phenotype. Overall, we report a novel role for Cav-1 in TCR/Lck spatial distribution upon TCR triggering, which controls T-cell fate toward a regulatory phenotype. This alteration translated into a significant increase in the frequency of Tregs and reduced GVHD in vivo. PMID:26837700

  17. Neoantigen landscape dynamics during human melanoma-T cell interactions.

    PubMed

    Verdegaal, Els M E; de Miranda, Noel F C C; Visser, Marten; Harryvan, Tom; van Buuren, Marit M; Andersen, Rikke S; Hadrup, Sine R; van der Minne, Caroline E; Schotte, Remko; Spits, Hergen; Haanen, John B A G; Kapiteijn, Ellen H W; Schumacher, Ton N; van der Burg, Sjoerd H

    2016-08-01

    Recognition of neoantigens that are formed as a consequence of DNA damage is likely to form a major driving force behind the clinical activity of cancer immunotherapies such as T-cell checkpoint blockade and adoptive T-cell therapy. Therefore, strategies to selectively enhance T-cell reactivity against genetically defined neoantigens are currently under development. In mouse models, T-cell pressure can sculpt the antigenicity of tumours, resulting in the emergence of tumours that lack defined mutant antigens. However, whether the T-cell-recognized neoantigen repertoire in human cancers is constant over time is unclear. Here we analyse the stability of neoantigen-specific T-cell responses and the antigens they recognize in two patients with stage IV melanoma treated by adoptive T-cell transfer. The T-cell-recognized neoantigens can be selectively lost from the tumour cell population, either by overall reduced expression of the genes or loss of the mutant alleles. Notably, loss of expression of T-cell-recognized neoantigens was accompanied by development of neoantigen-specific T-cell reactivity in tumour-infiltrating lymphocytes. These data demonstrate the dynamic interactions between cancer cells and T cells, which suggest that T cells mediate neoantigen immunoediting, and indicate that the therapeutic induction of broad neoantigen-specific T-cell responses should be used to avoid tumour resistance. PMID:27350335

  18. 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

    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 x μm(-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

  19. 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.μm-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

  20. I spy alloreactive T cells.

    PubMed

    Alegre, Maria-Luisa

    2015-01-28

    High-throughput sequencing of the T cell receptor Vβ 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

  1. Acquisition of a functional T cell receptor during T lymphocyte development is enforced by HEB and E2A transcription factors.

    PubMed

    Jones, Mary Elizabeth; Zhuang, Yuan

    2007-12-01

    The T cell receptor (TCR) is required for positive selection and the subsequent transition from the CD4(+)CD8(+) double-positive (DP) to the CD4(+) or CD8(+) single-positive (SP) stage of alphabeta T cell development. The molecular mechanism that maintains DP fate prior to the acquisition of a functional TCR is not clear. We have shown here that the structurally and functionally related transcription factors HEB and E2A work together to maintain DP fate and to control the DP to SP transition. Simultaneous deletion of HEB and E2A in DP thymocytes was sufficient for DP to SP transition independent of TCR. Loss of HEB and E2A allowed DP cells to bypass the requirement for TCR-mediated positive selection, downregulate DP-associated genes, and upregulate SP-specific genes. These results identify HEB and E2A as the gatekeepers that maintain cells at the DP stage of development until a functional alphabetaTCR is produced. PMID:18093538

  2. Role of Regulatory T Cells and Inhibitory Molecules in the Development of Immune Exhaustion During Human Immunodeficiency Virus Type 1 Infection.

    PubMed

    Gonzalez, Sandra Milena; Zapata, Wildeman; Rugeles, María Teresa

    2016-01-01

    One of the key hallmarks of chronic human immunodeficiency virus type 1 (HIV-1) infection is the persistent immune activation triggered since early stages of the infection, followed by the development of an exhaustion phenomena, which leads to the inability of immune cells to respond appropriately to the virus and other pathogens, constituting the acquired immunodeficiency syndrome (AIDS); this exhausting state is characterized by a loss of effector functions of immune cells such as proliferation, production of cytokine, as well as cytotoxic potential and it has been attributable to an increased response of regulatory T cells and recently also to the expression in different cell populations of inhibitory molecules, such as programmed death receptor-1 (PD-1), cytotoxic T lymphocyte antigen-4 (CTLA-4), T cell immunoglobulin-3 (Tim-3), and lymphocyte activation gene-3 (LAG-3). The importance of these molecules relies on the possibility to restore the immune response once these molecules are blocked, constituting a potential therapeutic target for treatment during HIV infection. In this regard, we explored the available data evaluating the functional role of Treg cells and inhibitory molecules during the infection in both blood and gut-associated lymphoid tissue (GALT) and their contribution to the development of immune exhaustion and progression to AIDS, as well as their therapeutic potential. PMID:26566019

  3. Regulatory T cells are baby's best friends.

    PubMed

    Teles, Ana; Zenclussen, Ana Claudia; Schumacher, Anne

    2013-04-01

    Regulatory T cells (Treg) are one of the most and best studied immune cell population during human and murine pregnancy, and there is a general consent about their expansion during pregnancy. However, the identification of new and more reliable Treg markers during the last years resulted in some controversies about the kinetics of various Treg subsets at different pregnancy stages. No doubt exists regarding the importance of Treg for a normal pregnancy as pregnancy complications like spontaneous abortion and preeclampsia could be associated with a reduced Treg number and activity. In future, more attention should be paid to bring established data from the bench to the bedside to force the development of adequate therapies for treatment of pregnancy complications. In this article, we summarize previous and recent data on several aspects of Treg biology during human and murine pregnancy. PMID:23289369

  4. 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

  5. Failure of T cell homing, reduced CD4/CD8alphaalpha intraepithelial lymphocytes, and inflammation in the gut of vitamin D receptor KO mice.

    PubMed

    Yu, Sanhong; Bruce, Danny; Froicu, Monica; Weaver, Veronika; Cantorna, Margherita T

    2008-12-30

    Specific pathogen-free IL-10 KO mice failed to develop inflammatory bowel disease (IBD), whereas IL-10/vitamin D receptor (VDR) double KO mice developed fulminating IBD. WT CD4 T cells inhibited experimental IBD, while VDR KO CD4 T cells failed to suppress IBD. VDR KO mice had normal numbers and functions of regulatory T cells. The percentages of IL-17- and IFN-gamma-secreting T cells in the gut of mice reconstituted with WT and VDR KO CD4 T cells were also not different. Instead, there were twice as many CD8alphaalpha intraepithelial lymphocytes (IEL) in mice that were reconstituted with WT CD4 T cells than in mice reconstituted with VDR KO CD4 T cells. Furthermore, VDR KO mice had reduced numbers of CD8alphaalpha IEL, absent CD4/CD8alphaalpha populations, and as a result low IL-10 production in the IEL. The lack of CD8alphaalpha IEL was due in part to decreased CCR9 expression on T cells that resulted in the failure of the VDR KO T cells to home to the small intestine. We conclude that the VDR mediates T cell homing to the gut and as a result the VDR KO mouse has reduced numbers of CD8alphaalpha IEL with low levels of IL-10 leading to increased inflammatory response to the normally harmless commensal flora. PMID:19095793

  6. Follicular Helper T Cells.

    PubMed

    Vinuesa, Carola G; Linterman, Michelle A; Yu, Di; MacLennan, Ian C M

    2016-05-20

    Although T cell help for B cells was described several decades ago, it was the identification of CXCR5 expression by B follicular helper T (Tfh) cells and the subsequent discovery of their dependence on BCL6 that led to the recognition of Tfh cells as an independent helper subset and accelerated the pace of discovery. More than 20 transcription factors, together with RNA-binding proteins and microRNAs, control the expression of chemotactic receptors and molecules important for the function and homeostasis of Tfh cells. Tfh cells prime B cells to initiate extrafollicular and germinal center antibody responses and are crucial for affinity maturation and maintenance of humoral memory. In addition to the roles that Tfh cells have in antimicrobial defense, in cancer, and as HIV reservoirs, regulation of these cells is critical to prevent autoimmunity. The realization that follicular T cells are heterogeneous, comprising helper and regulatory subsets, has raised questions regarding a possible division of labor in germinal center B cell selection and elimination. PMID:26907215

  7. 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

  8. Dynamic mapping of normal human hippocampal development.

    PubMed

    Gogtay, Nitin; Nugent, Tom F; Herman, David H; Ordonez, Anna; Greenstein, Deanna; Hayashi, Kiralee M; Clasen, Liv; Toga, Arthur W; Giedd, Jay N; Rapoport, Judith L; Thompson, Paul M

    2006-01-01

    The hippocampus, which plays an important role in memory functions and emotional responses, has distinct subregions subserving different functions. Because the volume and shape of the hippocampus are altered in many neuropsychiatric disorders, it is important to understand the trajectory of normal hippocampal development. We present the first dynamic maps to reveal the anatomical sequence of normal human hippocampal development. A novel hippocampal mapping technique was applied to a database of prospectively obtained brain magnetic resonance imaging (MRI) scans (100 scans in 31 children and adolescents), scanned every 2 yr for 6-10 yr between ages 4 and 25. Our results establish that the structural development of the human hippocampus is remarkably heterogeneous, with significant differences between posterior (increase over time) and anterior (loss over time) subregions. These distinct developmental trajectories of hippocampal subregions may parallel differences in their functional development. PMID:16826559

  9. Adult T-Cell Leukemia/Lymphoma (HTLV-1)

    MedlinePlus

    ... gentic material made of DNA, but instead carry RNA. These viruses selectively infect only T-cells. Only ... potential to inject its genetic material (DNA or RNA) into normal cells. Once inside the normal cells, ...

  10. 4-1BB ligand signaling to T cells limits T cell activation.

    PubMed

    Eun, So-Young; Lee, Seung-Woo; Xu, Yanfei; Croft, Michael

    2015-01-01

    4-1BB ligand (4-1BBL) and its receptor, 4-1BB, are both induced on T cells after activation, but little is known about the role of 4-1BBL. In this study we show that 4-1BBL can transmit signals that limit T cell effector activity under tolerogenic conditions. Cross-linking 4-1BBL inhibited IL-2 production in vitro, primarily with suboptimal TCR stimulation. Furthermore, naive 4-1BBL-deficient OT-II transgenic T cells displayed a greater conversion to effector T cells in vivo when responding to soluble OVA peptide in wild-type hosts, whereas development of Foxp3(+) regulatory T cells was not altered. A greater number of effector T cells also differentiated from naive wild-type OT-II T cells when transferred into 4-1BB-deficient hosts, suggesting that APC-derived 4-1BB is likely to trigger 4-1BBL. Indeed, effector T cells that could not express 4-1BBL accumulated in larger numbers in vitro when stimulated with 4-1BB-expressing mesenteric lymph node dendritic cells. 4-1BBL was expressed on T cells when Ag presentation was limiting, and 4-1BBL was aberrantly expressed at very high levels on T cells that could not express 4-1BB. Trans-ligation, Ab capture, and endocytosis experiments additionally showed that T cell-intrinsic 4-1BB regulated internalization of membrane 4-1BBL, implying that the strong induction of 4-1BB on T cells may counteract the suppressive function of 4-1BBL by limiting its availability. These data suggest that 4-1BBL expressed on T cells can restrain effector T cell development, creating a more favorable regulatory T cell to effector cell balance under tolerogenic conditions, and this may be particularly active in mucosal barrier tissues where 4-1BB-expressing regulatory dendritic cells present Ag. PMID:25404362

  11. A Natural Variant of the T Cell Receptor-Signaling Molecule Vav1 Reduces Both Effector T Cell Functions and Susceptibility to Neuroinflammation

    PubMed Central

    Kassem, Sahar; Bernard, Isabelle; Dejean, Anne S.; Liblau, Roland; Fournié, Gilbert J.; Colacios, Céline

    2016-01-01

    The guanine nucleotide exchange factor Vav1 is essential for transducing T cell antigen receptor signals and therefore plays an important role in T cell development and activation. Our previous genetic studies identified a locus on rat chromosome 9 that controls the susceptibility to neuroinflammation and contains a non-synonymous polymorphism in the major candidate gene Vav1. To formally demonstrate the causal implication of this polymorphism, we generated a knock-in mouse bearing this polymorphism (Vav1R63W). Using this model, we show that Vav1R63W mice display reduced susceptibility to experimental autoimmune encephalomyelitis (EAE) induced by MOG35-55 peptide immunization. This is associated with a lower production of effector cytokines (IFN-γ, IL-17 and GM-CSF) by autoreactive CD4 T cells. Despite increased proportion of Foxp3+ regulatory T cells in Vav1R63W mice, we show that this lowered cytokine production is intrinsic to effector CD4 T cells and that Treg depletion has no impact on EAE development. Finally, we provide a mechanism for the above phenotype by showing that the Vav1R63W variant has normal enzymatic activity but reduced adaptor functions. Together, these data highlight the importance of Vav1 adaptor functions in the production of inflammatory cytokines by effector T cells and in the susceptibility to neuroinflammation. PMID:27438086

  12. Pre-TCRα supports CD3-dependent reactivation and expansion of TCRα-deficient primary human T-cells

    PubMed Central

    Galetto, Román; Lebuhotel, Celine; Poirot, Laurent; Gouble, Agnès; Toribio, Maria L; Smith, Julianne; Scharenberg, Andrew

    2014-01-01

    Chimeric antigen receptor technology offers a highly effective means for increasing the anti-tumor effects of autologous adoptive T-cell immunotherapy, and could be made widely available if adapted to the use of allogeneic T-cells. Although gene-editing technology can be used to remove the alloreactive potential of third party T-cells through destruction of either the α or β T-cell receptor (TCR) subunit genes, this approach results in the associated loss of surface expression of the CD3 complex. This is nonetheless problematic as it results in the lack of an important trophic signal normally mediated by the CD3 complex at the cell surface, potentially compromising T-cell survival in vivo, and eliminating the potential to expand TCR-knockout cells using stimulatory anti-CD3 antibodies. Here, we show that pre-TCRα, a TCRα surrogate that pairs with TCRβ chains to signal proper TCRβ folding during T-cell development, can be expressed in TCRα knockout mature T-cells to support CD3 expression at the cell surface. Cells expressing pre-TCR/CD3 complexes can be activated and expanded using standard CD3/CD28 T-cell activation protocols. Thus, heterologous expression of pre-TCRα represents a promising technology for use in the manufacturing of TCR-deficient T-cells for adoptive immunotherapy applications. PMID:26015965

  13. DCIR2+ cDC2 DCs and Zbtb32 Restore CD4+ T-Cell Tolerance and Inhibit Diabetes.

    PubMed

    Price, Jeffrey D; Hotta-Iwamura, Chie; Zhao, Yongge; Beauchamp, Nicole M; Tarbell, Kristin V

    2015-10-01

    During autoimmunity, the normal ability of dendritic cells (DCs) to induce T-cell tolerance is disrupted; therefore, autoimmune disease therapies based on cell types and molecular pathways that elicit tolerance in the steady state may not be effective. To determine which DC subsets induce tolerance in the context of chronic autoimmunity, we used chimeric antibodies specific for DC inhibitory receptor 2 (DCIR2) or DEC-205 to target self-antigen to CD11b(+) (cDC2) DCs and CD8(+) (cDC1) DCs, respectively, in autoimmune-prone nonobese diabetic (NOD) mice. Antigen presentation by DCIR2(+) DCs but not DEC-205(+) DCs elicited tolerogenic CD4(+) T-cell responses in NOD mice. β-Cell antigen delivered to DCIR2(+) DCs delayed diabetes induction and induced increased T-cell apoptosis without interferon-γ (IFN-γ) or sustained expansion of autoreactive CD4(+) T cells. These divergent responses were preceded by differential gene expression in T cells early after in vivo stimulation. Zbtb32 was higher in T cells stimulated with DCIR2(+) DCs, and overexpression of Zbtb32 in T cells inhibited diabetes development, T-cell expansion, and IFN-γ production. Therefore, we have identified DCIR2(+) DCs as capable of inducing antigen-specific tolerance in the face of ongoing autoimmunity and have also identified Zbtb32 as a suppressive transcription factor that controls T cell-mediated autoimmunity. PMID:26070317

  14. Roscovitine Suppresses CD4+ T Cells and T Cell-Mediated Experimental Uveitis

    PubMed Central

    Zhang, Zili; Liu, Qi; Leskov, Konstantin S.; Wu, Xiumei; Duan, Jie; Zhang, Gary L.; Hall, Mark; Rosenbaum, James T.

    2013-01-01

    Background T cells are essential for the development of uveitis and other autoimmune diseases. After initial activation, CD4+ lymphocytes express the co-stimulatory molecule OX40 that plays an important role in T cell proliferation. Cyclin dependent kinase 2 (CdK2) plays a pivotal role in the cell cycle transition from G1 to S phase. In addition, recent research has implicated CdK2 in T cell activation. Thus, we sought to test the immunosuppressive effect of roscovitine, a potent CdK2 inhibitor, on CD4+ T cell activation, proliferation, and function. Design and Methods Mouse CD4+ T cells were activated by anti-CD3 and anti-CD28 antibodies. The expression of OX40, CD44, and CdK2 were analyzed by flow cytometry. In addition, cell cycle progression and apoptosis of control and roscovitine-treated T lymphocytes were measured by BrdU incorporation and annexin V assay, respectively. Furthermore, the immunoregulatory effect of roscovitine was evaluated in both ovalbumin-induced uveitis and experimental autoimmune uveitis (EAU) models. Results In this study, we found that T cell activation induced OX40 expression. Cell cycle analysis showed that more CD4+OX40+ cells entered S phase than OX40- T cells. Concurrently, CD4+OX40+ cells had a higher level of CdK2 expression. Roscovitine treatment blocked activated CD4+ cells from entering S phase. In addition, roscovitine not only reduced the viability of CD4+ lymphocytes but also suppressed T cell activation and cytokine production. Finally, roscovitine significantly attenuated the severity of T cell-dependent, OX40-enhanced uveitis. Conclusion These results implicate CdK2 in OX40-augmented T cell response and expansion. Furthermore, this study suggests that roscovitine is a novel, promising, therapeutic agent for treating T cell-mediated diseases such as uveitis. PMID:24260551

  15. A Variable CD3+ T-Cell Frequency in Peripheral Blood Lymphocytes Associated with Type 1 Diabetes Mellitus Development in the LEW.1AR1-iddm Rat

    PubMed Central

    Arndt, Tanja; Jörns, Anne; Weiss, Heike; Tiedge, Markus; Hedrich, Hans-Jürgen; Lenzen, Sigurd; Wedekind, Dirk

    2013-01-01

    Purpose The LEW.1AR1-iddm rat is an animal model of human type 1 diabetes mellitus (T1DM), which arose through a spontaneous mutation within the MHC-congenic inbred strain LEW.1AR1 (RT1r2). In contrast to the diabetes-resistant LEW.1AR1 background strain in LEW.1AR1-iddm rats a highly variable T-cell frequency could be observed in peripheral blood lymphocytes (PBLs). Methods In this study we therefore characterised the T-cell repertoire within the PBLs of the two strains by flow cytometry analysis and identified the CD3+ T-cell phenotype and its possible linkage to diabetes susceptibility. To map loci conferring susceptibility to variable CD3+ T-cell frequency, backcross strains (N2) were generated with the genetically divergent BN and PAR rats for microsatellite analysis. Results The LEW.1AR1-iddm rat strain was characterised by a higher variability of CD3+ T-cells in PBLs along with a slightly decreased mean value compared to the LEW.1AR1 background strain. The reason for this reduction was a decrease in the CD4+ T-cell count while the CD8+ T-cell proportion remained unchanged. However, both T-cell subpopulations showed a high variability. This resulted in a lower CD4+/CD8+ T-cell ratio than in LEW.1AR1 rats. Like LEW.1AR1-iddm rats all animals of the backcross populations, N2 BN and N2 PAR rats, also showed large variations of the CD3+ T-cell frequency. The phenotype of variable CD3+ T-cell frequency mapped to the telomeric region of chromosome 1 (RNO1), which is identical with the already known Iddm8 diabetes susceptibility region. The data indicate that a variable CD3+ T-cell frequency in PBLs is genetically linked to diabetes susceptibility in the LEW.1AR1-iddm rat. Conclusion The T-cell variability in PBLs could be related to the previously reported imbalance between regulatory and effector T-cell populations which results in beta-cell autoimmunity. Since similar T-cell phenotypes have also been described in human T1DM the identification of the functional

  16. T cells, precocious aging, and familial neoplasia.

    PubMed

    Fudenberg, H H; Schuman, S H; Goust, J M; Jorgenson, R

    1978-01-01

    A 15-year-old girl presented with precocious aging and was found to have low levels of active and total T cells. Family history revealed a high familial incidence of cancer on both the maternal and paternal sides, and activ T cell levels were found to be low in several living family members. The patient developed osteogenic sarcoma 13 months after initial study. Since our previous studies have reported low active and total T cells in patients with cancer, the present results suggest that subjects with low active T cells should be monitored frequently to detect possible neoplasia in it early stages. They also suggest that impaired cellular immunity in humans is associated with, if not the cause of, accelerated aging. PMID:304823

  17. 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

  18. Reactive oxygen species differentially affect T cell receptor-signaling pathways.

    PubMed

    Cemerski, Saso; Cantagrel, Alain; Van Meerwijk, Joost P M; Romagnoli, Paola

    2002-05-31

    Oxidative stress plays an important role in the induction of T lymphocyte hyporesponsiveness observed in several human pathologies including cancer, rheumatoid arthritis, leprosy, and AIDS. To investigate the molecular basis of oxidative stress-induced T cell hyporesponsiveness, we have developed an in vitro system in which T lymphocytes are rendered hyporesponsive by co-culture with oxygen radical-producing activated neutrophils. We have observed a direct correlation between the level of T cell hyporesponsiveness induced and the concentration of reactive oxygen species produced. Moreover, induction of T cell hyporesponsiveness is blocked by addition of N-acetyl cysteine, Mn(III)tetrakis(4-benzoic acid)porphyrin chloride, and catalase, confirming the critical role of oxidative stress in this system. The pattern of tyrosine-phosphorylated proteins was profoundly altered in hyporesponsive as compared with normal T cells. In hyporesponsive T cells, T cell receptor (TCR) ligation no longer induced phospholipase C-gamma1 activation and caused reduced Ca(2+) flux. In contrast, despite increased levels of ERK1/2 phosphorylation, TCR-dependent activation of mitogen-activated protein kinase ERK1/2 was unaltered in hyporesponsive T lymphocytes. A late TCR-signaling event such as caspase 3 activation was as well unaffected in hyporesponsive T lymphocytes. Our data indicate that TCR-signaling pathways are differentially affected by physiological levels of oxidative stress and would suggest that although "hyporesponsive" T cells have lost certain effector functions, they may have maintained or gained others. PMID:11916964

  19. T Cells and Gene Regulation: The Switching On and Turning Up of Genes after T Cell Receptor Stimulation in CD8 T Cells

    PubMed Central

    Conley, James M.; Gallagher, Michael P.; Berg, Leslie J.

    2016-01-01

    Signaling downstream of the T cell receptor (TCR) is directly regulated by the dose and affinity of peptide antigen. The strength of TCR signaling drives a multitude of T cell functions from development to differentiation. CD8 T cells differentiate into a diverse pool of effector and memory cells after activation, a process that is critical for pathogen clearance and is highly regulated by TCR signal strength. T cells rapidly alter their gene expression upon activation. Multiple signaling pathways downstream of the TCR activate transcription factors, which are critical for this process. The dynamics between proximal TCR signaling, transcription factor activation and CD8 T cell function are discussed here. We propose that inducible T cell kinase (ITK) acts as a rheostat for gene expression. This unique regulation of TCR signaling by ITK provides a possible signaling mechanism for the promotion of a diverse T cell repertoire in response to pathogen. PMID:26973653

  20. Blind T-cell homeostasis in CD4-deficient mice.

    PubMed

    Adleman, L M; Wofsy, D

    1996-04-01

    Recently, it has been proposed that normal T-cell count is maintained by a homeostatic mechanism which is "blind" to the distinction between CD4+ T cells and CD8+ T cells. Interest in this blind homeostasis hypothesis (BHH) stems in part from its implications regarding the pathogenesis and treatment of HIV infection. In this report, BHH was tested in CD4-deficient mice. We found that as predicted by BHH, despite the absence of CD4+ T cells, CD4-deficient mice maintain normal absolute T-cell counts in the blood and spleen primarily through a marked increase in CD8+ T cells. These findings provide strong new support for BHH. PMID:8601219

  1. Development of Human Anti-Murine T-cell Receptor Antibodies in Both Responding and Non-responding Patients Enrolled in TCR Gene Therapy Trials

    PubMed Central

    Davis, Jeremy L.; Theoret, Marc R.; Zheng, Zhili; Lamers, Cor; Rosenberg, Steven A.; Morgan, Richard A.

    2010-01-01

    Purpose Immune responses to gene-modified cells are a concern in the field of human gene therapy as they may impede effective treatment. We conducted two clinical trials in which cancer patients were treated with lymphocytes genetically engineered to express murine T cell receptors (mTCR) specific for tumor-associated antigens p53 and gp100. Experimental Design Twenty-six patients treated with autologous lymphocytes expressing mTCR had blood and serum samples available for analysis. Patient sera were assayed for development of a humoral immune response. Adoptive cell transfer characteristics were analyzed to identify correlates to immune response. Results Six of 26 (23%) patients post-treatment sera exhibited specific binding of human anti-mTCR antibodies to lymphocytes transduced with the mTCR. Antibody development was found in both responding and non-responding patients. Three of these six patients post-treatment sera mediated a 60 – 99% inhibition of mTCR activity as measured by a reduction in antigen-specific IFN-γ release. Detailed analysis of post-treatment serum revealed that antibody binding was beta chain specific in one patient whereas it was alpha chain specific in another. Conclusions A subset of patients treated with mTCR engineered T-cells developed antibodies directed to the mTCR variable regions and not to the constant region domains common to all mTCR. Overall, the development of a host immune response was not associated with the level of transduced cell persistence or response to therapy. In summary, patients treated with mTCR can develop an immune response to gene-modified cells in a minority of cases, but this may not affect clinical outcome. PMID:21138872

  2. Toxicities of chimeric antigen receptor T cells: recognition and management.

    PubMed

    Brudno, Jennifer N; Kochenderfer, James N

    2016-06-30

    Chimeric antigen receptor (CAR) T cells can produce durable remissions in hematologic malignancies that are not responsive to standard therapies. Yet the use of CAR T cells is limited by potentially severe toxicities. Early case reports of unexpected organ damage and deaths following CAR T-cell therapy first highlighted the possible dangers of this new treatment. CAR T cells can potentially damage normal tissues by specifically targeting a tumor-associated antigen that is also expressed on those tissues. Cytokine release syndrome (CRS), a systemic inflammatory response caused by cytokines released by infused CAR T cells can lead to widespread reversible organ dysfunction. CRS is the most common type of toxicity caused by CAR T cells. Neurologic toxicity due to CAR T cells might in some cases have a different pathophysiology than CRS and requires different management. Aggressive supportive care is necessary for all patients experiencing CAR T-cell toxicities, with early intervention for hypotension and treatment of concurrent infections being essential. Interleukin-6 receptor blockade with tocilizumab remains the mainstay pharmacologic therapy for CRS, though indications for administration vary among centers. Corticosteroids should be reserved for neurologic toxicities and CRS not responsive to tocilizumab. Pharmacologic management is complicated by the risk of immunosuppressive therapy abrogating the antimalignancy activity of the CAR T cells. This review describes the toxicities caused by CAR T cells and reviews the published approaches used to manage toxicities. We present guidelines for treating patients experiencing CRS and other adverse events following CAR T-cell therapy. PMID:27207799

  3. 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

  4. Genomic landscape of cutaneous T cell lymphoma

    PubMed Central

    Choi, Jaehyuk; Goh, Gerald; Walradt, Trent; Hong, Bok S.; Bunick, Christopher G.; Chen, Kan; Bjornson, Robert D.; Maman, Yaakov; Wang, Tiffany; Tordoff, Jesse; Carlson, Kacie; Overton, John D.; Liu, Kristina J.; Lewis, Julia M.; Devine, Lesley; Barbarotta, Lisa; Foss, Francine M.; Subtil, Antonio; Vonderheid, Eric C.; Edelson, Richard L.; Schatz, David G.; Boggon, Titus J.; Girardi, Michael; Lifton, Richard P.

    2015-01-01

    Cutaneous T cell lymphoma (CTCL) is a non-Hodgkin lymphoma of skin-homing T lymphocytes. We performed exome and whole genome DNA sequence and RNA sequencing on purified CTCL and matched normal cells. The results implicate mutations in 17 genes in CTCL pathogenesis, including genes involved in T cell activation and apoptosis, NFκB signaling, chromatin remodeling, and DNA damage response. CTCL is distinctive in that somatic copy number variants (SCNVs) comprise 92% of all driver mutations (mean of 11.8 pathogenic SCNVs vs. 1.0 somatic single nucleotide variants per CTCL). These findings have implications for novel therapeutics. PMID:26192916

  5. Cre-loxP-Mediated Recombination between the SIL and SCL Genes Leads to a Block in T-Cell Development at the CD4-CD8- to CD4+CD8+ Transition1

    PubMed Central

    Yue Cheng; Zhenhua Zhang; Slape, Christopher; Aplan, Peter D.

    2007-01-01

    In the most common form of stem cell leukemia (SCL) gene rearrangement, an interstitial deletion of 82 kb brings SCL under the control of regulatory elements that normally govern expression of the ubiquitously expressed SCL interrupting locus (SIL) gene, which is located directly upstream of SCL. To investigate the effect of this fusion in a mouse model, a bacterial artificial chromosome (BAC) clone containing both human SIL and SCL genes was isolated, and loxP sites were inserted into intron 1 of both the SIL and SCL genes, corresponding to the sites at which recombination occurs in human T-cell acute lymphocytic leukemia patients. This BAC clone was used to generate transgenic SILloxloxSCL mice. These transgenic mice were subsequently bred to Lck-Cre mice that express the Cre recombinase specifically in the thymus. The BAC transgene was recombined between the two loxP sites in over 50% of the thymocytes from SILloxloxSCL/Cre double-transgenic mice, bringing the SCL gene under the direct control of SIL regulatory elements. Aberrant SCL gene expression in the thymus was verified by reverse transcription-polymerase chain reaction. Using FACS analysis, we found that mice carrying both SILloxloxSCL and Cre transgenes have increased CD4-/CD8- thymocytes compared with transgene-negative mice. In the spleen, these transgenic mice show a marked reduction in the number of mature CD4+ or CD8+ cells. These results demonstrate that conditional activation of SCL under control of SIL regulatory elements can impair normal T-cell development. PMID:17460775

  6. Adoptive T-cell therapy.

    PubMed

    Lokhorst, H M; Liebowitz, D

    1999-01-01

    Adoptive immunotherapy, or the transfer of immunocompetent cells, has been shown to be a promising new strategy for treatment of a variety of malignancies, including leukemia and non-Hodgkin's lymphoma. The possibility that it may likewise benefit patients with multiple myeloma is now being explored by researchers in Europe and the United States. Two alternatives, one using donor leukocyte infusions (DLIs) and the other using autologous T cells, are described. In the Netherlands, researchers studied the use of DLIs in 17 patients with multiple myeloma who relapsed after bone marrow transplant (BMT). Of 16 evaluable patients, 10 (62%) responded, with six (37%) achieving a complete response (CR). After a median follow-up duration of 28 months, five patients relapsed and five remained in remission. Graft-versus-host disease (GVHD) developed in nine patients. In the United States, adoptive immunotherapy is currently being tested in eight patients with chemotherapy-resistant lymphoma. Autologous T cells were obtained prior to BMT and expanded using an anti-CD3/CD28 culture system. After BMT, the cells were reinfused into the patient. At approximately day 14, granulocyte levels began to recover in the six evaluable patients, and levels remained relatively stable over the posttreatment course. Two patients developed severe autoimmune toxicity, which responded to treatment in one and resolved spontaneously in the other. PMID:9989486

  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. 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...

  9. Deletion of Pten in CD45-expressing cells leads to development of T-cell lymphoblastic lymphoma but not myeloid malignancies

    PubMed Central

    Mirantes, Cristina; Dosil, Maria Alba; Hills, David; Yang, Jian; Eritja, Núria; Santacana, Maria; Gatius, Sònia; Vilardell, Felip; Medvinsky, Alexander; Matias-Guiu, Xavier

    2016-01-01

    Since its discovery in the late 1990s, Pten has turned out to be one of the most important tumor suppressor genes. Pten loss results in increased activation of the phosphatidylinositol 3-kinase/Akt signaling pathway, which is associated with increased proliferation, survival, and neoplastic growth. Here, we have addressed the effects of conditional deletion of Pten in hematopoietic cells by crossing Pten conditional knockout mice with a knock-in mouse expressing the Cre recombinase in the CD45 locus. CD45 is also known as leukocyte common antigen, and it is expressed in virtually all white cells and in hematopoietic stem cells. Using a reporter mouse, we demonstrate that CD45:Cre mouse displays recombinase activity in both myeloid and lymphoid cells. However, deletion of Pten in CD45-expressing cells induces development of T-cell acute lymphoblastic leukemia and lymphoma, but not other hematologic malignancies. PMID:26773036

  10. Deletion of Pten in CD45-expressing cells leads to development of T-cell lymphoblastic lymphoma but not myeloid malignancies.

    PubMed

    Mirantes, Cristina; Dosil, Maria Alba; Hills, David; Yang, Jian; Eritja, Núria; Santacana, Maria; Gatius, Sònia; Vilardell, Felip; Medvinsky, Alexander; Matias-Guiu, Xavier; Dolcet, Xavier

    2016-04-14

    Since its discovery in the late 1990s, Pten has turned out to be one of the most important tumor suppressor genes. Pten loss results in increased activation of the phosphatidylinositol 3-kinase/Akt signaling pathway, which is associated with increased proliferation, survival, and neoplastic growth. Here, we have addressed the effects of conditional deletion of Pten in hematopoietic cells by crossing Pten conditional knockout mice with a knock-in mouse expressing the Cre recombinase in the CD45 locus. CD45 is also known as leukocyte common antigen, and it is expressed in virtually all white cells and in hematopoietic stem cells. Using a reporter mouse, we demonstrate that CD45:Cre mouse displays recombinase activity in both myeloid and lymphoid cells. However, deletion of Pten in CD45-expressing cells induces development of T-cell acute lymphoblastic leukemia and lymphoma, but not other hematologic malignancies. PMID:26773036

  11. Memory T-cell competition for bone marrow seeding.

    PubMed

    Di Rosa, Francesca; Santoni, Angela

    2003-03-01

    The presence in the bone marrow of memory CD8 T cells is well recognized. However, it is still largely unclear how T-cell migration from the lymphoid periphery to the bone marrow is regulated. In the present report, we show that antigen-specific CD4 T cells, as well as antigen-specific CD8 T cells, localize to the bone marrow of immunized mice, and are sustained there over long periods of time. To investigate the rules governing T-cell migration to the bone marrow, we generated chimeric mice in which the lymphoid periphery contained two genetically or phenotypically distinct groups of T cells, one of which was identical to the host. We then examined whether a distinct type of T cell had an advantage over the others in the colonization of bone marrow. Our results show that whereas ICAM1 and CD18 molecules are both involved in homing to lymph nodes, neither is crucial for T-cell bone marrow colonization. We also observed that memory-phenotype CD44high T cells, but not virgin-type CD44-/low T cells, preferentially home to the bone marrow upon adoptive transfer to normal young mice, but not to thymectomized old recipients where an existing memory T-cell pool precludes their free access. Thus, T-cell colonization of the bone marrow uses distinct molecules from those implicated in lymph node homing, and is regulated both by the properties of the T cell and by the competitive efficacy of other T cells inhabiting the same, saturable niche. This implies that the homing potential of an individual lymphocyte is not merely an intrinsic property of the cell, but rather a property of the lymphoid system taken as a whole. PMID:12603595

  12. The Role of Lymphatic Niches in T Cell Differentiation

    PubMed Central

    Capece, Tara; Kim, Minsoo

    2016-01-01

    Long-term immunity to many viral and bacterial pathogens requires CD8+ memory T cell development, and the induction of long-lasting CD8+ memory T cells from a naïve, undifferentiated state is a major goal of vaccine design. Formation of the memory CD8+ T cell compartment is highly dependent on the early activation cues received by naïve CD8+ T cells during primary infection. This review aims to highlight the cellularity of various niches within the lymph node and emphasize recent evidence suggesting that distinct types of T cell activation and differentiation occur within different immune contexts in lymphoid organs. PMID:27306645

  13. Isolation of Double Negative αβ T Cells from the Kidney

    PubMed Central

    Martina, Maria N.; Bandapalle, Samantha; Rabb, Hamid; Hamad, Abdel R.

    2014-01-01

    There is currently no standard protocol for the isolation of DN T cells from the non-lymphoid tissues despite their increasingly reported involvement in various immune responses. DN T cells are a unique immune cell type that has been implicated in regulating immune and autoimmune responses and tolerance to allotransplants1-6. DN T cells are, however, rare in peripheral blood and secondary lymphoid organs (spleen and lymph nodes), but are major residents of the normal kidney. Very little is known about their pathophysiologic function7 due to their paucity in the periphery. We recently described a comprehensive phenotypic and functional analysis of this population in the kidney8 in steady state and during ischemia reperfusion injury. Analysis of DN T cell function will be greatly enhanced by developing a protocol for their isolation from the kidney. Here, we describe a novel protocol that allows isolation of highly pure ab CD4+ CD8+ T cells and DN T cells from the murine kidney. Briefly, we digest kidney tissue using collagenase and isolate kidney mononuclear cells (KMNC) by density gradient. This is followed by two steps to enrich hematopoietic T cells from 3% to 70% from KMNC. The first step consists of a positive selection of hematopoietic cells using a CD45+ isolation kit. In the second step, DN T cells are negatively isolated by removal of non-desired cells using CD4, CD8, and MHC class II monoclonal antibodies and CD1d α-galcer tetramer. This strategy leads to a population of more than 90% pure DN T cells. Surface staining with the above mentioned antibodies followed by FACs analysis is used to confirm purity. PMID:24893925

  14. The role of gamma delta T cells in haematopoietic stem cell transplantation.

    PubMed

    Minculescu, L; Sengeløv, H

    2015-06-01

    Although haematopoietic stem cell transplantation (HSCT) is a potential curative treatment for haematological malignancies, it is still a procedure associated with substantial morbidity and mortality due to toxicity, graft-versus-host disease (GVHD) and relapse. Recent attempts of developing safer transplantation modalities increasingly focuses on selective cell depletion and graft engineering with the aim of retaining beneficial immune donor cells for the graft-versus-leukaemia (GVL) effect. In this context, the adoptive and especially innate effector functions of γδ T cells together with clinical studies investigating the effect of γδ T cells in relation to HSCT are reviewed. In addition to phospho-antigen recognition by the γδ T cell receptor (TCR), γδ T cells express receptors of the natural killer (NK) and natural cytotoxicity (NCR) families enabling them to recognize and kill leukaemia cells. Antigen recognition independent from the major histocompatibility complex (MHC) allows for the theoretical possibility of mediating GVL without an allogeneic response in terms of GVHD. Early studies on the impact of γδ T cells in HSCT have reported conflicting results. Recent studies, however, do suggest an overall favourable effect of high γδ T cell immune reconstitution after HSCT; patients with elevated numbers of γδ T cells had a significantly higher overall survival rate and a decreased rate of acute GVHD compared to patients with low or normal γδ T cell counts. Further research in terms of effector mechanisms, subtypes and tissue distribution during the course of HSCT is needed to assess the potentially beneficial effects of γδ T cells in this setting. PMID:25753378

  15. Peritoneal cavity regulatory B cells (B10 cells) modulate IFN-γ+CD4+ T cell numbers during colitis development in mice.

    PubMed

    Maseda, Damian; Candando, Kathleen M; Smith, Susan H; Kalampokis, Ioannis; Weaver, Casey T; Plevy, Scott E; Poe, Jonathan C; Tedder, Thomas F

    2013-09-01

    The spleen regulatory B cell subset with the functional capacity to express IL-10 (B10 cells) modulates both immune responses and autoimmune disease severity. However, the peritoneal cavity also contains relatively high frequencies of functionally defined IL-10-competent B10 cells. In this study, peritoneal cavity B10 cells shared similar cell surface phenotypes with their spleen counterparts. However, peritoneal cavity B10 cells were 10-fold more frequent among B cells than occurred within the spleen, intestinal tract, or mesenteric lymph nodes and were present at higher proportions among the phenotypically defined peritoneal B1a > B1b > B2 cell subpopulations. The development or localization of B10 cells within the peritoneal cavity was not dependent on the presence of commensal microbiota, T cells, IL-10 or B10 cell IL-10 production, or differences between their fetal liver or adult bone marrow progenitor cell origins. The BCR repertoire of peritoneal cavity B10 cells was diverse, as occurs in the spleen, and predominantly included germline-encoded VH and VL regions commonly found in either the conventional or B1 B cell compartments. Thereby, the capacity to produce IL-10 appears to be an intrinsic functional property acquired by clonally diverse B cells. Importantly, IL-10 production by peritoneal cavity B cells significantly reduced disease severity in spontaneous and induced models of colitis by regulating neutrophil infiltration, colitogenic CD4(+) T cell activation, and proinflammatory cytokine production during colitis onset. Thus, the numerically small B10 cell subset within the peritoneal cavity has regulatory function and is important for maintaining homeostasis within gastrointestinal tissues and the immune system. PMID:23918988

  16. CD31 is required on CD4+ T cells to promote T cell survival during Salmonella infection

    PubMed Central

    Ross, Ewan A; Coughlan, Ruth E; Flores-Langarica, Adriana; Bobat, Saeeda; Marshall, Jennifer L; Hussain, Khiyam; Charlesworth, James; Abhyankar, Nikita; Hitchcock, Jessica; Gil, Cristina; López-Macías, Constantino; Henderson, Ian R; Khan, Mahmood; Watson, Steve P; MacLennan, Ian C M; Buckley, Christopher D; Cunningham, Adam F

    2011-01-01

    Haematopoietic cells constitutively express CD31/PECAM1 a signalling, adhesion receptor associated with controlling responses to inflammatory stimuli. Although expressed on CD4+ T cells, its function on these cells is unclear. To address this we have used a model of systemic Salmonella infection that induces high levels of T cell activation and depends upon CD4+ T cells for resolution. Infection of CD31-deficient (CD31KO) mice demonstrates that these mice fail to control infection effectively. During infection, CD31KO mice have diminished numbers of total CD4+ T cells and IFN-γ-secreting Th1 cells. This is despite a higher proportion of CD31KO CD4+ T cells exhibiting an activated phenotype, and an undiminished capacity to prime normally and polarize to Th1. Reduced numbers of T cells reflected the increased propensity of naive and activated CD31KO T cells to undergo apoptosis after infection compared to wild-type (WT) T cells. Using adoptive transfer experiments we show that loss of CD31 on CD4+ T cells alone is sufficient to account for the defective CD31KO T cell accumulation. These data are consistent with CD31 helping to control T cell activation as in its absence T cells have a greater propensity to become activated, resulting in increased susceptibility to become apoptotic. The impact of CD31 loss on T cell homeostasis becomes most pronounced during severe, inflammatory and immunological stresses such as those caused by systemic Salmonella infection. This identifies a novel role for CD31 in regulating CD4 T cell homeostasis. PMID:21734076

  17. T cell subpopulations.

    PubMed

    Romagnani, Sergio

    2014-01-01

    The role of allergen-specific CD4+ effector type 2 helper (Th2) cells in the pathogenesis of allergic disorders is an established fact. Th2 cells produce interleukin (IL)-4 and IL-13, which induce immunoglobulin E production by B cells, and IL-5 that allows recruitment of eosinophils. Two main mechanisms control the Th2-mediated allergic inflammation: immune deviation (or Th1 redirection) and immune regulation. Regulatory T (Treg) cells exhibit a CD4+ phenotype and include Foxp3-positive thymic and induced Tregs, as well as Foxp3-negative IL-10-producing cells. Both immune deviation and immune regulation evoked by the maternal and newborn microbial environment probably operate in preventing allergen-specific Th2 responses. However, microbe-related protection from allergy seems to mainly depend on epigenetically controlled acetylation of the IFNG promoter of CD4+ T cells. Even Th17 and Th9 cells, as well as invariant NKT cells, have been implicated in the pathogenesis of allergic disorders, but their role is certainly more limited. Recently, innate lymphoid type 2 cells (ILC2) have been found to be able to produce high amounts of IL-5 and IL-13 in response to stimulation with IL-25 and IL-33 produced by non-immune cells. Together with Th2 cells, ILC2 may contribute to the induction and maintenance of allergic inflammation. PMID:24925396

  18. Chronic Inflammation and γδ T Cells.

    PubMed

    Fay, Nathan S; Larson, Emily C; Jameson, Julie M

    2016-01-01

    The epithelial tissues of the skin, lungs, reproductive tract, and intestines are the largest physical barriers the body has to protect against infection. Epithelial tissues are woven with a matrix of immune cells programed to mobilize the host innate and adaptive immune responses. Included among these immune cells are gamma delta T lymphocytes (γδ T cells) that are unique in their T cell receptor usage, location, and functions in the body. Stress reception by γδ T cells as a result of traumatic epithelial injury, malignancy, and/or infection induces γδ T cell activation. Once activated, γδ T cells function to repair tissue, induce inflammation, recruit leukocytes, and lyse cells. Many of these functions are mediated via the production of cytokines and growth factors upon γδ T cell activation. Pathogenesis of many chronic inflammatory diseases involves γδ T cells; some of which are exacerbated by their presence, while others are improved. γδ T cells require a delicate balance between their need for acute inflammatory mediators to function normally and the detrimental impact imparted by chronic inflammation. This review will focus on the recent progress made in understanding how epithelial γδ T cells influence the pathogenesis of chronic inflammatory diseases and how a balance between acute and chronic inflammation impacts γδ T cell function. Future studies will be important to understand how this balance is achieved. PMID:27303404

  19. Impaired T cell function in argininosuccinate synthetase deficiency

    PubMed Central

    Tarasenko, Tatyana N.; Gomez-Rodriguez, Julio; McGuire, Peter J.

    2015-01-01

    ASS1 is a cytosolic enzyme that plays a role in the conversion of citrulline to arginine. In human and mouse tissues, ASS1 protein is found in several components of the immune system, including the thymus and T cells. However, the role of ASS1 in these tissues remains to be defined. Considerable attention has been focused recently on the role of metabolism in T cell differentiation and function. Based on the expression of ASS1 in the immune system, we hypothesized that ASS1 deficiency would result in T cell defects. To evaluate this question, we characterized immune function in hypomorphic fold/fold mice. Analysis of splenic T cells by flow cytometry showed a marked reduction in T cell numbers with normal expression of activation surface markers. Gene therapy correction of liver ASS1 to enhance survival resulted in a partial recovery of splenic T cells for characterization. In vitro and in vivo studies demonstrated the persistence of the ASS1 enzyme defect in T cells and abnormal T cell differentiation and function. Overall, our work suggests that ASS1 plays a role in T cell function, and deficiency produces primary immune dysfunction. In addition, these data suggest that patients with ASS1 deficiency (citrullinemia type I) may have T cell dysfunction. PMID:25492936

  20. Chronic Inflammation and γδ T Cells

    PubMed Central

    Fay, Nathan S.; Larson, Emily C.; Jameson, Julie M.

    2016-01-01

    The epithelial tissues of the skin, lungs, reproductive tract, and intestines are the largest physical barriers the body has to protect against infection. Epithelial tissues are woven with a matrix of immune cells programed to mobilize the host innate and adaptive immune responses. Included among these immune cells are gamma delta T lymphocytes (γδ T cells) that are unique in their T cell receptor usage, location, and functions in the body. Stress reception by γδ T cells as a result of traumatic epithelial injury, malignancy, and/or infection induces γδ T cell activation. Once activated, γδ T cells function to repair tissue, induce inflammation, recruit leukocytes, and lyse cells. Many of these functions are mediated via the production of cytokines and growth factors upon γδ T cell activation. Pathogenesis of many chronic inflammatory diseases involves γδ T cells; some of which are exacerbated by their presence, while others are improved. γδ T cells require a delicate balance between their need for acute inflammatory mediators to function normally and the detrimental impact imparted by chronic inflammation. This review will focus on the recent progress made in understanding how epithelial γδ T cells influence the pathogenesis of chronic inflammatory diseases and how a balance between acute and chronic inflammation impacts γδ T cell function. Future studies will be important to understand how this balance is achieved. PMID:27303404

  1. Auto-reactive T cells revised. Overestimation based on methodology?

    PubMed

    Thorlacius-Ussing, Gorm; Sørensen, Jesper F; Wandall, Hans H; Pedersen, Anders Elm

    2015-05-01

    Autoreactive T cells have been identified in most autoimmune diseases and recently even in healthy individuals. Similar, T cells that recognize either wild-type or tumorspecific tumor antigens have been increasingly reported to develop spontaneously in cancer patients. This insight has become possible mainly due to novel immunoassays which have revolutionized the discovery of rare antigen specific T cells. At present, the major dogma that explains this increasing number of reports of autoreactive T cells is that autoreactive T cells are counteracted by CD4+CD25+ regulatory T (Treg) cells in vivo, in particular in healthy individuals, whereas dysfunction in Tregs or Treg responsiveness may unmask the autoreactive T cell responses in patients with autoimmune diseases. However, studies that identify autoreactive T cells are usually performed by culturing T cells with antigen presenting cells loaded with E. coli produced recombinant protein or unmodified synthetic HLA binding peptides. Our concern is that this approach may ignore the presence of natural genetic variation and post-translational modifications such as e.g. the complex nature of N- and O-linked glycosylation of mammalian proteins. Thus, T cell antigen reactivities identified with unmodified antigens in vitro may in part represent in vitro T cell activation against neo-epitopes and not true in vivo autoreactivity as postulated. This methodological problem may have implications for the interpretation of the frequent reporting of autoreactive T cells in autoimmunity, T cell responses to wild-type tumor antigens in cancer patients and most important for the increasing reports on naïve T cells with specificity against self-antigens in healthy individuals. Here, we discuss and provide examples for the possibility that the experimental methodology applied to document T cell reactivity against unmodified protein or peptide may lead to overinterpretation of the reported frequencies of autoreactive CD4+ and CD8+ T

  2. 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.

  3. Elevation and persistence of CD8 T-cells in HIV infection: the Achilles heel in the ART era

    PubMed Central

    Cao, Wei; Mehraj, Vikram; Kaufmann, Daniel E; Li, Taisheng; Routy, Jean-Pierre

    2016-01-01

    Introduction HIV infection leads to a disturbed T-cell homeostasis, featured by a depletion of CD4 T-cells and a persistent elevation of CD8 T-cells over disease progression. Most effort of managing HIV infection has been focused on CD4 T-cell recovery, while changes in the CD8 compartment were relatively underappreciated in the past. Methods A comprehensive literature review of publications in English language was conducted using major electronic databases. Our search was focused on factors contributing to CD8 T-cell dynamics in HIV infection and following antiretroviral therapy (ART). Discussion Normalization of CD8 counts is seldom observed even with optimal CD4 recovery following long-term treatment. Initiation of ART in primary HIV infection leads to enhanced normalization of CD8 count compared with long-term ART initiated in chronic infection. Importantly, such CD8 elevation in treated HIV infection is associated with an increased risk of inflammatory non-AIDS-related clinical events independent of CD4 T-cell recovery. The mechanisms underlying CD8 persistence remain largely unknown, which may include bystander activation, exhaustion and immunosenescence of CD8 T-cells. The information provided herein will lead to a better understanding of factors associated with CD8 persistence and contribute to the development of strategies aiming at CD8 normalization. Conclusions Persistence of CD8 T-cell elevation in treated HIV-infected patients is associated with an increased risk of non-AIDS-related events. Now that advances in ART have led to decreased AIDS-related opportunistic diseases, more attention has been focused on reducing non-AIDS events and normalizing persistent CD8 T-cell elevation. PMID:26945343

  4. 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

  5. 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

  6. Metabolic regulation of T cell differentiation and function

    PubMed Central

    Park, Benjamin V.; Pan, Fan

    2016-01-01

    Upon encountering pathogens, T cells mount immune responses by proliferating, increasing cellular mass and differentiating. These cellular changes impose significant energetic challenges on T cells. It was believed that TCR and cytokine-mediated signaling are dominant dictators of T cell-mediated immune responses. Recently, it was recognized that T cells utilize metabolic transporters and metabolic sensors that allow them to rapidly respond to nutrient-limiting inflammatory environments. Metabolic sensors allow T cells to find a balance between energy consumption (anabolic metabolism) and production (catabolic metabolism) in order to mount effective immune responses. Also, metabolic regulators interact with cytokine-dependent transcriptional regulators, suggesting a more integrative and advanced model of T cell activation and differentiation. In this review, we will discuss recent discoveries regarding the roles of metabolic regulators in effector and memory T cell development and their interaction with canonical transcription factors. PMID:26277275

  7. Cytokine expression by invariant natural killer T cells is tightly regulated throughout development and settings of type-2 inflammation

    PubMed Central

    O'Brien, T F; Bao, K; Dell'Aringa, M; Ang, W X G; Abraham, S; Reinhardt, R L

    2016-01-01

    Invariant natural killer T (iNKT) cells produce cytokines interleukin-4 (IL-4) and IL-13 during type-2 inflammatory responses. However, the nature in which iNKT cells acquire type-2 cytokine competency and the precise contribution of iNKT cell–derived IL-4 and IL-13 in vivo remains unclear. Using IL-13-reporter mice to fate-map cytokine–expressing cells in vivo, this study reveals that thymic iNKT cells express IL-13 early during development, and this IL-13-expressing intermediate gives rise to mature iNKT1, iNKT2, and iNKT17 subsets. IL-4 and IL-13 reporter mice also reveal that effector iNKT2 cells produce IL-4 but little IL-13 in settings of type-2 inflammation. The preferential production of IL-4 over IL-13 in iNKT2 cells results in part from their reduced GATA-3 expression. In summary, this work helps integrate current models of iNKT cell development, and further establishes non-coordinate production of IL-4 and IL-13 as the predominant pattern of type-2 cytokine expression among innate cells in vivo. PMID:26349658

  8. Development of γδ T cell subset responses in gnotobiotic pigs infected with human rotaviruses and colonized with probiotic lactobacilli

    PubMed Central

    Wen, Ke; Li, Guohua; Zhang, Wei; Azevedo, Marli SP; Saif, Linda J; Liu, Fangning; Bui, Tammy; Yousef, Ahmed; Yuan, Lijuan

    2011-01-01

    γδ T cell responses are induced by various viral and bacterial infections. Different γδ T cells contribute to activation and regulation of the inflammatory response and to epithelial repair. How γδ T cells respond to rotavirus infection and how the colonization of probiotics influences the γδ T cell response were unknown. In this study, we evaluated by multicolor flow cytometry the frequencies and distribution of total γδ T cells and three major subsets (CD2−CD8−, CD2+CD8− and CD2+CD8+) in ileum, spleen and blood of gnotobiotic (Gn) pigs at early (3–5 days) and late phases (28 days) after rotavirus infection. The Gn pigs were inoculated with the virulent human rotavirus Wa strain and colonized with a mixture of two strains of probiotics Lactobacillus acidophilus and Lactobacillus reuteri. In naive pigs, the highest frequency of total γδ T cells was found in blood, followed by spleen and ileum at the early age (8–10 days old) whereas in older pigs (32 days of age) the highest frequency of total γδ T cells was found in ileum and spleen followed by blood. Rotavirus infection significantly increased frequencies of intestinal total γδ T cells and the putatively regulatory CD2+CD8+ γδ T cell subset and decreased frequencies of the putatively proinflammatory CD8− subsets in ileum, spleen and blood at post-infection days (PID) 3 or 5. The three γδ T cell subsets distributed and responded differently after rotavirus infection and/or lactobacilli colonization. The CD2+CD8+ subset contributed the most to the expansion of total γδ T cells after rotavirus infection in ileum because more than 77% of the total γδ T cells there were CD2+CD8+ cells. There was an additive effect between lactobacilli and rotavirus in inducing total γδ T cell expansion in ileum at PID 5. The overall effect of lactobacilli colonization versus rotavirus infection on frequencies of the CD2+CD8+ γδ T cell subset in ileum was similar; however, rotavirus-infected pigs

  9. Memory CD8+ T cells use cell intrinsic lipolysis to support the metabolic programming necessary for development

    PubMed Central

    O’Sullivan, David; van der Windt, Gerritje J. W.; Ching-Cheng Huang, Stanley; Curtis, Jonathan D.; Chang, Chih-Hao; Buck, Michael D.; Qiu, Jing; Smith, Amber M.; Lam, Wing Y.; DiPlato, Lisa M.; Hsu, Fong-Fu; Birnbaum, Morris J.; Pearce, Edward J.; Pearce, Erika L.

    2014-01-01

    Summary Generation of CD8+ memory T (TM) cells requires metabolic reprogramming that is characterized by enhanced mitochondrial fatty acid oxidation (FAO). However, where the fatty acids (FA) that fuel this process come from remains unclear. We found that while CD8+ TM cells engaged higher levels of FAO, they acquired substantially fewer long-chain FA from their external environment than CD8+ effector T (TE) cells. Rather than using extracellular FA directly, TM cells used extracellular glucose to support FAO and oxidative phosphorylation (OXPHOS), suggesting that lipids must be synthesized to generate the substrates needed for FAO. We have demonstrated that TM cells rely on cell intrinsic expression of the lysosomal hydrolase LAL (lysosomal acid lipase) to mobilize FA for FAO and TM cell development. Our observations link LAL to metabolic reprogramming in lymphocytes and show that cell intrinsic lipolysis is deterministic for TM cell fate. PMID:25001241

  10. T cells from CLL patients exhibit features of T-cell exhaustion but retain capacity for cytokine production

    PubMed Central

    Davies, Jeffrey K.; McClanahan, Fabienne; Fatah, Rewas; Iqbal, Sameena; Agrawal, Samir; Ramsay, Alan G.; Gribben, John G.

    2013-01-01

    T-cell exhaustion, originally described in chronic viral infections, was recently reported in solid and hematologic cancers. It is not defined whether exhaustion contributes to T-cell dysfunction observed in chronic lymphocytic leukemia (CLL). We investigated the phenotype and function of T cells from CLL patients and age-matched controls. CD8+ and CD4+ T cells from CLL patients had increased expression of exhaustion markers CD244, CD160, and PD1, with expansion of a PD1+BLIMP1HI subset. These molecules were most highly expressed in the expanded population of effector T cells in CLL. CLL CD8+ T cells showed functional defects in proliferation and cytotoxicity, with the cytolytic defect caused by impaired granzyme packaging into vesicles and nonpolarized degranulation. In contrast to virally induced exhaustion, CLL T cells showed increased production of interferon-γ and TNFα and increased expression of TBET, and normal IL2 production. These defects were not restricted to expanded populations of cytomegalovirus (CMV)–specific cells, although CMV seropositivity modulated the distribution of lymphocyte subsets, the functional defects were present irrespective of CMV serostatus. Therefore, although CLL CD8+ T cells exhibit features of T-cell exhaustion, they retain the ability to produce cytokines. These findings also exclude CMV as the sole cause of T-cell defects in CLL. PMID:23247726

  11. T cells conditioned with MDSC show an increased anti-tumor activity after adoptive T cell based immunotherapy

    PubMed Central

    Raber, Patrick L.; Sierra, Rosa A.; Thevenot, Paul T.; Shuzhong, Zhang; Wyczechowska, Dorota D.; Kumai, Takumi; Celis, Esteban; Rodriguez, Paulo C.

    2016-01-01

    The success of adoptive T cell-based immunotherapy (ACT) in cancer is limited in part by the accumulation of myeloid-derived suppressor cells (MDSC), which block several T cell functions, including T cell proliferation and the expression of various cytotoxic mediators. Paradoxically, the inhibition of CD8+ T cell differentiation into cytotoxic populations increased their efficacy after ACT into tumor-bearing hosts. Therefore, we aimed to test the impact of conditioning CD8+ T cells with MDSC on their differentiation potential and ACT efficacy. Our results indicate that MDSC impaired the progression of CD8+ T cells into effector populations, without altering their activation status, production of IL-2, or signaling through the T cell receptor. In addition, culture of CD8+ T cells with MDSC resulted in an increased ACT anti-tumor efficacy, which correlated with a higher frequency of the transferred T cells and elevated IFNγ production. Interestingly, activated CD62L+ CD8+ Tcells were responsible for the enhanced anti-tumor activity showed by MDSC-exposed T cells. Additional results showed a decreased protein synthesis rate and lower activity of the mammalian/mechanistic target of rapamycin (mTOR) in T cells conditioned with MDSC. Silencing of the negative mTOR regulator tuberous sclerosis complex-2 in T cells co-cultured with MDSC restored mTOR activity, but resulted in T cell apoptosis. These results indicate that conditioning of T cells with MDSC induces stress survival pathways mediated by a blunted mTOR signaling, which regulated T cell differentiation and ACT efficacy. Continuation of this research will enable the development of better strategies to increase ACT responses in cancer. PMID:27007050

  12. Biased signaling pathways via CXCR3 control the development and function of CD4+ T cell subsets.

    PubMed

    Karin, Nathan; Wildbaum, Gizi; Thelen, Marcus

    2016-06-01

    Structurally related chemotactic cytokines (chemokines) regulate cell trafficking through interactions with 7-transmembrane domain, G protein-coupled receptors. Biased signaling or functional selectivity is a concept that describes a situation where a 7-transmembrane domain receptor preferentially activates one of several available cellular signaling pathways. It can be divided into 3 distinct cases: ligand bias, receptor bias, and tissue or cell bias. Many studies, including those coming from our lab, have shown that only a limited number of chemokines are key drivers of inflammation. We have referred to them as "driver chemokines." They include the CXCR3 ligands CXCL9 and CXCL10, the CCR2 ligand CCL2, all 3 CCR5 ligands, and the CCR9 ligand CCL25. As for CXCR3, despite the proinflammatory nature of CXCL10 and CXCL9, transgenic mice lacking CXCR3 display an aggravated manifestation of different autoimmune disease, including Type I diabetes and experimental autoimmune encephalomyelitis. Recently, we showed that whereas CXCL9 and CXCL10 induce effector Th1/Th17 cells to promote inflammation, CXCL11, with a relatively higher binding affinity to CXCR3, drives the development of the forkhead box P3-negative IL-10(high) T regulatory 1 cell subset and hence, dampens inflammation. We also showed that CXCL9/CXCL10 activates a different signaling cascade than CXCL11, despite binding to the same receptor, CXCR3, which results in these diverse biologic activities. This provides new evidence for the role of biased signaling in regulating biologic activities, in which CXCL11 induces ligand bias at CXCR3 and receptor-biased signaling via atypical chemokine receptor 3. PMID:26657511

  13. The G protein-coupled receptor T-cell death-associated gene 8 (TDAG8) facilitates tumor development by serving as an extracellular pH sensor.

    PubMed

    Ihara, Yuichiro; Kihara, Yasuyuki; Hamano, Fumie; Yanagida, Keisuke; Morishita, Yasuyuki; Kunita, Akiko; Yamori, Takao; Fukayama, Masashi; Aburatani, Hiroyuki; Shimizu, Takao; Ishii, Satoshi

    2010-10-01

    Tumors often are associated with a low extracellular pH, which induces a variety of cellular events. However, the mechanisms by which tumor cells recognize and react to the acidic environment have not been fully elucidated. T-cell death-associated gene 8 (TDAG8) is an extracellular pH-sensing G protein-coupled receptor that is overexpressed in various tumors and tumor cell lines. In this report, we show that TDAG8 on the surface of tumor cells facilitates tumor development by sensing the acidic environment. Overexpression of TDAG8 in mouse Lewis lung carcinoma (LLC) cells enhanced tumor development in animal models and rendered LLC cells resistant to acidic culture conditions by increasing activation of protein kinase A and extracellular signal-regulated kinase in vitro. Moreover, shRNA-mediated knockdown of endogenous TDAG8 in NCI-H460 human non-small cell lung cancer cells reduced cell survival in an acidic environment in vitro as well as tumor development in vivo. Microarray analyses of tumor-containing lung tissues of mice injected with TDAG8-expressing LLC cells revealed up-regulation of genes related to cell growth and glycolysis. These results support the hypothesis that TDAG8 enhances tumor development by promoting adaptation to the acidic environment to enhance cell survival/proliferation. TDAG8 may represent a therapeutic target for arresting tumor growth. PMID:20855608

  14. Mechanisms of T cell organotropism.

    PubMed

    Fu, Hongmei; Ward, Eleanor Jayne; Marelli-Berg, Federica M

    2016-08-01

    Protective immunity relies upon T cell differentiation and subsequent migration to target tissues. Similarly, immune homeostasis requires the localization of regulatory T cells (Tregs) to the sites where immunity takes place. While naïve T lymphocytes recirculate predominantly in secondary lymphoid tissue, primed T cells and activated Tregs must traffic to the antigen rich non-lymphoid tissue to exert effector and regulatory responses, respectively. Following priming in draining lymph nodes, T cells acquire the 'homing receptors' to facilitate their access to specific tissues and organs. An additional level of topographic specificity is provided by T cells receptor recognition of antigen displayed by the endothelium. Furthermore, co-stimulatory signals (such as those induced by CD28) have been shown not only to regulate T cell activation and differentiation, but also to orchestrate the anatomy of the ensuing T cell response. We here review the molecular mechanisms supporting trafficking of both effector and regulatory T cells to specific antigen-rich tissues. PMID:27038487

  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. T cells induce terminal differentiation of transformed B cells to mature plasma cell tumors.

    PubMed

    Hilbert, D M; Shen, M Y; Rapp, U R; Rudikoff, S

    1995-01-31

    Major interest in the analysis of mature plasma cell neoplasias of mice and humans has focused on identification of precursor cells that give rise to mature malignant plasma cells. Although several laboratories have recently suggested that such cells are present in the granulomas of pristane-treated mice and the bone marrow of some multiple myeloma patients, the in vivo cellular interactions required for their differentiation into mature plasma cell tumors remains unclear. Given the extensive interactions of peripheral T cells and normal B cells, we assessed the potential role of T cells in plasma-cell tumor development, by using a myc, raf-containing retrovirus, J3V1, to induce plasmacytomas in normal BALB/c mice, T-cell-deficient nude mice, and T-cell-reconstituted nude mice. The B-lineage tumors arising in normal BALB/c mice were uniformly mature plasmacytomas, most of which secreted immunoglobulin. In contrast, nude mice yielded predominantly non-immunoglobulin-secreting B-cell lymphomas with a phenotype characteristic of peripheral B cells. T-cell reconstitution of nude mice prior to tumor induction resulted in a shift from B-cell lymphomas to plasmacytomas. These results imply that transformation can occur prior to terminal differentiation of B cells and that such transformed cells can be driven to terminal differentiation by peripheral T cells. These findings further suggest that, in human multiple myeloma, the ability of T cells to influence the differentiation state of transformed B cells may provide a mechanism by which malignant plasma cells found in the bone marrow could arise from clonotypically related less-mature B cells found in both the bone marrow and periphery. PMID:7846031

  17. Decreased SAP Expression in T Cells from Patients with Systemic Lupus Erythematosus Contributes to Early Signaling Abnormalities and Reduced IL-2 Production.

    PubMed

    Karampetsou, Maria P; Comte, Denis; Kis-Toth, Katalin; Terhorst, Cox; Kyttaris, Vasileios C; Tsokos, George C

    2016-06-15

    T cells from patients with systemic lupus erythematosus (SLE) display a number of abnormalities, including increased early signaling events following engagement of the TCR. Signaling lymphocytic activation molecule family cell surface receptors and the X-chromosome-defined signaling lymphocytic activation molecule-associated protein (SAP) adaptor are important in the development of several immunocyte lineages and modulating the immune response. We present evidence that SAP protein levels are decreased in T cells and in their main subsets isolated from 32 women and three men with SLE, independent of disease activity. In SLE T cells, SAP protein is also subject to increased degradation by caspase-3. Forced expression of SAP in SLE T cells normalized IL-2 production, calcium (Ca(2+)) responses, and tyrosine phosphorylation of a number of proteins. Exposure of normal T cells to SLE serum IgG, known to contain anti-CD3/TCR Abs, resulted in SAP downregulation. We conclude that SLE T cells display reduced levels of the adaptor protein SAP, probably as a result of continuous T cell activation and degradation by caspase-3. Restoration of SAP levels in SLE T cells corrects the overexcitable lupus T cell phenotype. PMID:27183584

  18. 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.

  19. Regulation of the development of asthmatic inflammation by in situ CD4(+)Foxp3 (+) T cells in a mouse model of late allergic asthma.

    PubMed

    Nakashima, Tomomi; Hayashi, Toshiharu; Mizuno, Takuya

    2014-10-01

    CD4(+)Foxp3(+)T cells (Tregs) mediate homeostatic peripheral tolerance by suppressing helper T2 cells in allergy. However, the regulation of asthmatic inflammation by local (in situ) Tregs in asthma remains unclear. BALB/c mice sensitized and challenged with ovalbumin (OVA) (asthma group) developed asthmatic inflammation with eosinophils and lymphocytes, but not mast cells. The number of Tregs in the circulation, pulmonary lymph nodes (pLNs), and thymi significantly decreased in the asthma group compared to the control group without OVA sensitization and challenge in the effector phase. The development of asthmatic inflammation is inversely related to decreased Tregs with reduced mRNA expression such as interleukin (IL)-4, transforming growth factor-β1, and IL-10, but not interferon-γ, in pLNs. Moreover, M2 macrophages increased in the local site. The present study suggests that Tregs, at least in part, may regulate the development of asthmatic inflammation by cell-cell contact and regional cytokine productions. PMID:24854160

  20. T-cell adoptive immunotherapy using tumor-infiltrating T cells and genetically engineered TCR-T cells.

    PubMed

    Ikeda, Hiroaki

    2016-07-01

    Immunotherapy has received the expectation that it should contribute to the therapy of cancer patients for >100 years. At long last, recent clinical trials of immunotherapy with immune checkpoint inhibitors and adoptive cell therapy with genetically engineered T cells have reported their remarkable efficacies. Nowadays, it is expected that T-cell adoptive immunotherapy can not only control tumor progression but even cure cancer in some patients. Conversely, severe adverse events associated with efficacy have frequently been reported in clinical trials, suggesting that the assessment and control of safety will be indispensable in the future development of the therapy. New approaches in T-cell adoptive immunotherapy such as reduction of adverse events, targeting of new antigens or utilization of allogeneic cells will open a new gate for less harmful and more effective immunological treatment of cancer patients. PMID:27127191

  1. Adoptive Immunotherapy using Regulatory T cells and Virus-specific T cells Derived from Cord Blood

    PubMed Central

    Hanley, Patrick J.; Bollard, Catherine M.; Brunstein, Claudio G

    2014-01-01

    Cord blood transplantation, an alternative to traditional stem cell transplants (bone marrow or peripheral blood stem cell transplantation), is an attractive option for patients lacking suitable stem cell transplant donors. Cord blood units have also proven to be a valuable donor source for the development of cellular therapeutics. Virus-specific T cells and regulatory T cells are two cord blood derived products that have shown promise in early phase clinical trials to prevent and/or treat viral infections and graft-versus-host disease (GvHD), respectively. Here we describe how current strategies utilizing cord blood-derived regulatory T cells and virus-specific T cells have been developed to improve outcomes for cord blood transplant recipients. PMID:25632003

  2. Efficacy and toxicity management of CAR-T-cell immunotherapy: a matter of responsiveness control or tumour-specificity?

    PubMed

    Alonso-Camino, Vanesa; Harwood, Seandean Lykke; Álvarez-Méndez, Ana; Alvarez-Vallina, Luis

    2016-04-15

    Chimaeric antigen receptor (CAR)-expressing T-cells have demonstrated potent clinical efficacy in patients with haematological malignancies. However, the use of CAR-T-cells targeting solid tumour-associated antigens (TAAs) has been limited by organ toxicities related to activation of T-cell effector functions through the CAR. Most existing CARs recognize TAAs, which are also found in normal tissues. CAR-T-cell-mediated destruction of normal tissues constitutes a major roadblock to CAR-T-cell therapy, and must be avoided or mitigated. There is a broad range of strategies for modulating antigen responsiveness of CAR-T-cells, with varying degrees of complexity. Some of them might ameliorate the acute and chronic toxicities associated with current CAR constructs. However, further embellishments to CAR therapy may complicate clinical implementation and possibly create new immunogenicity issues. In contrast, the development of CARs targeting truly tumour-specific antigens might circumvent on-target/off-tumour toxicities without adding additional complexity to CAR-T-cell therapies, but these antigens have been elusive and may require novel selection strategies for their discovery. PMID:27068947

  3. CD8 T cell memory recall is enhanced by novel direct interactions with CD4 T cells enabled by MHC class II transferred from APCs.

    PubMed

    Romagnoli, Pablo A; Premenko-Lanier, Mary F; Loria, Gilbert D; Altman, John D

    2013-01-01

    Protection against many intracellular pathogens is provided by CD8 T cells, which are thought to need CD4 T cell help to develop into effective memory CD8 T cells. Because murine CD8 T cells do not transcribe MHC class II (MHC-II) genes, several models have proposed antigen presenting cells (APCs) as intermediaries required for CD4 T cells to deliver their help to CD8 T cells. Here, we demonstrate the presence of MHC-II molecules on activated murine CD8 T cells in vitro as well as in vivo. These MHC-II molecules are acquired via trogocytosis by CD8 T cells from their activating APCs, particularly CD11c positive dendritic cells (DCs). Transferred MHC-II molecules on activated murine CD8 T cells were functionally competent in stimulating specific indicator CD4 T cells. CD8 T cells that were "helped" in vitro and subsequently allowed to rest in vivo showed enhanced recall responses upon challenge compared to "helpless" CD8 T cells; in contrast, no differences were seen upon immediate challenge. These data indicate that direct CD8:CD4 T cell interactions may significantly contribute to help for CD8 T cells. Furthermore, this mechanism may enable CD8 T cells to communicate with different subsets of interacting CD4 T cells that could modulate immune responses. PMID:23441229

  4. 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.

  5. Simian T-lymphotropic Virus-associated lymphoma in 2 naturally infected baboons: T-cell clonal expansion and immune response during tumor development.

    PubMed

    d'Offay, Jean M; Eberle, Richard; Wolf, Roman F; Kosanke, Stanley D; Doocy, Kelly R; Ayalew, Sahlu; Mansfeild, Keith G; White, Gary L

    2013-06-01

    Two young female baboons naturally infected with simian T-lymphotropic virus type 1 (STLV1) were euthanized due to chronic respiratory disease that was unresponsive to treatment. Massive lymphocytic infiltration of the lung interstitium suggested a diagnosis of STLV-associated lymphoma. In each case, the diagnosis was confirmed through inverse PCR (IPCR) that detected monoclonally integrated STLV1 provirus in cellular DNA extracted from lymphoma tissue and peripheral blood cells (PBC). One dominant STLV1-infected T-cell clone and 3 minor clones were detected in PBC from each baboon. Using archived PBC DNA and primers within the proviral genome and chromosomal DNA flanking the STLV1 integration sites in PCR analyses, we determined that the dominant clone in one baboon had first appeared approximately 8 mo after infection and had circulated for 4 y before clinical disease developed. ELISA testing of archived serum revealed that both baboons seroconverted to the p19 and p24 gag proteins and the envelope gp46 protein but not to the viral tax protein. Titers to p24 and gp46 rose significantly after infection and remained relatively constant until death, whereas titers to p19 increased with time. Although spontaneous STLV1-associated lymphomas have been described in baboons, the STLV1-associated lymphomas described here occurred in 2 relatively young baboons, both of whom had become infected with STLV at 3 to 4 y of age and developed lymphoma within 5 y of infection. PMID:23759532

  6. APRIL modulates B and T cell immunity

    PubMed Central

    Stein, Jens V.; López-Fraga, Marta; Elustondo, Fernando A.; Carvalho-Pinto, Carla E.; Rodríguez, Dolores; Gómez-Caro, Ruth; de Jong, Joan; Martínez-A, Carlos; Medema, Jan Paul; Hahne, Michael

    2002-01-01

    The TNF-like ligands APRIL and BLyS are close relatives and share the capacity to bind the receptors TACI and BCMA. BLyS has been shown to play an important role in B cell homeostasis and autoimmunity, but the biological role of APRIL remains less well defined. Analysis of T cells revealed an activation-dependent increase in APRIL mRNA expression. We therefore generated mice expressing APRIL as a transgene in T cells. These mice appeared normal and showed no signs of B cell hyperplasia. Transgenic T cells revealed a greatly enhanced survival in vitro as well as enhanced survival of staphylococcal enterotoxin B–reactive CD4+ T cells in vivo, which both directly correlate with elevated Bcl-2 levels. Analysis of humoral responses to T cell–dependent antigens in the transgenic mice indicated that APRIL affects only IgM but not IgG responses. In contrast, T cell–independent type 2 (TI-2) humoral response was enhanced in APRIL transgenic mice. As TACI was previously reported to be indispensable for TI-2 antibody formation, these results suggest a role for APRIL/TACI interactions in the generation of this response. Taken together, our data indicate that APRIL is involved in the induction and/or maintenance of T and B cell responses. PMID:12070306

  7. CIP2A Promotes T-Cell Activation and Immune Response to Listeria monocytogenes Infection.

    PubMed

    Côme, Christophe; Cvrljevic, Anna; Khan, Mohd Moin; Treise, Irina; Adler, Thure; Aguilar-Pimentel, Juan Antonio; Au-Yeung, Byron; Sittig, Eleonora; Laajala, Teemu Daniel; Chen, Yiling; Oeder, Sebastian; Calzada-Wack, Julia; Horsch, Marion; Aittokallio, Tero; Busch, Dirk H; Ollert, Markus W; Neff, Frauke; Beckers, Johannes; Gailus-Durner, Valerie; Fuchs, Helmut; Hrabě de Angelis, Martin; Chen, Zhi; Lahesmaa, Riitta; Westermarck, Jukka

    2016-01-01

    The oncoprotein Cancerous Inhibitor of Protein Phosphatase 2A (CIP2A) is overexpressed in most malignancies and is an obvious candidate target protein for future cancer therapies. However, the physiological importance of CIP2A-mediated PP2A inhibition is largely unknown. As PP2A regulates immune responses, we investigated the role of CIP2A in normal immune system development and during immune response in vivo. We show that CIP2A-deficient mice (CIP2AHOZ) present a normal immune system development and function in unchallenged conditions. However when challenged with Listeria monocytogenes, CIP2AHOZ mice display an impaired adaptive immune response that is combined with decreased frequency of both CD4+ T-cells and CD8+ effector T-cells. Importantly, the cell autonomous effect of CIP2A deficiency for T-cell activation was confirmed. Induction of CIP2A expression during T-cell activation was dependent on Zap70 activity. Thus, we reveal CIP2A as a hitherto unrecognized mediator of T-cell activation during adaptive immune response. These results also reveal CIP2AHOZ as a possible novel mouse model for studying the role of PP2A activity in immune regulation. On the other hand, the results also indicate that CIP2A targeting cancer therapies would not cause serious immunological side-effects. PMID:27100879

  8. CIP2A Promotes T-Cell Activation and Immune Response to Listeria monocytogenes Infection

    PubMed Central

    Cvrljevic, Anna; Khan, Mohd Moin; Treise, Irina; Adler, Thure; Aguilar-Pimentel, Juan Antonio; Au-Yeung, Byron; Sittig, Eleonora; Laajala, Teemu Daniel; Chen, Yiling; Oeder, Sebastian; Calzada-Wack, Julia; Horsch, Marion; Aittokallio, Tero; Busch, Dirk H.; Ollert, Markus W.; Neff, Frauke; Beckers, Johannes; Gailus-Durner, Valerie; Fuchs, Helmut; de Angelis, Martin Hrabě; Chen, Zhi; Lahesmaa, Riitta; Westermarck, Jukka

    2016-01-01

    The oncoprotein Cancerous Inhibitor of Protein Phosphatase 2A (CIP2A) is overexpressed in most malignancies and is an obvious candidate target protein for future cancer therapies. However, the physiological importance of CIP2A-mediated PP2A inhibition is largely unknown. As PP2A regulates immune responses, we investigated the role of CIP2A in normal immune system development and during immune response in vivo. We show that CIP2A-deficient mice (CIP2AHOZ) present a normal immune system development and function in unchallenged conditions. However when challenged with Listeria monocytogenes, CIP2AHOZ mice display an impaired adaptive immune response that is combined with decreased frequency of both CD4+ T-cells and CD8+ effector T-cells. Importantly, the cell autonomous effect of CIP2A deficiency for T-cell activation was confirmed. Induction of CIP2A expression during T-cell activation was dependent on Zap70 activity. Thus, we reveal CIP2A as a hitherto unrecognized mediator of T-cell activation during adaptive immune response. These results also reveal CIP2AHOZ as a possible novel mouse model for studying the role of PP2A activity in immune regulation. On the other hand, the results also indicate that CIP2A targeting cancer therapies would not cause serious immunological side-effects. PMID:27100879

  9. PLZF+ Innate T Cells Support the TGF-β-Dependent Generation of Activated/Memory-Like Regulatory T Cells

    PubMed Central

    Kang, Byung Hyun; Park, Hyo Jin; Park, Hi Jung; Lee, Jae-II; Park, Seong Hoe; Jung, Kyeong Cheon

    2016-01-01

    PLZF-expressing invariant natural killer T cells and CD4 T cells are unique subsets of innate T cells. Both are selected via thymocyte-thymocyte interaction, and they contribute to the generation of activated/memory-like CD4 and CD8 T cells in the thymus via the production of IL-4. Here, we investigated whether PLZF+ innate T cells also affect the development and function of Foxp3+ regulatory CD4 T cells. Flow cytometry analysis of the thymus and spleen from both CIITA transgenic C57BL/6 and wild-type BALB/c mice, which have abundant PLZF+ CD4 T cells and invariant natural killer T cells, respectively, revealed that Foxp3+ T cells in these mice exhibited a CD103+ activated/memory-like phenotype. The frequency of CD103+ regulatory T cells was considerably decreased in PLZF+ cell-deficient CIITATgPlzflu/lu and BALB/c.CD1d−/− mice as well as in an IL-4-deficient background, such as in CIITATgIL-4−/− and BALB/c.lL-4−/− mice, indicating that the acquisition of an activated/memory-like phenotype was dependent on PLZF+ innate T cells and IL-4. Using fetal thymic organ culture, we further demonstrated that IL-4 in concert with TGF-β enhanced the acquisition of the activated/memory-like phenotype of regulatory T cells. In functional aspects, the activated/memory-like phenotype of Treg cells was directly related to their suppressive function; regulatory T cells of CIITATgPIV−/− mice more efficiently suppressed ovalbumin-induced allergic airway inflammation compared with their counterparts from wild-type mice. All of these findings suggest that PLZF+ innate T cells also augmented the generation of activated/memory-like regulation via IL-4 production. PMID:27101876

  10. PLZF(+) Innate T Cells Support the TGF-β-Dependent Generation of Activated/Memory-Like Regulatory T Cells.

    PubMed

    Kang, Byung Hyun; Park, Hyo Jin; Park, Hi Jung; Lee, Jae-Ii; Park, Seong Hoe; Jung, Kyeong Cheon

    2016-06-30

    PLZF-expressing invariant natural killer T cells and CD4 T cells are unique subsets of innate T cells. Both are selected via thymocyte-thymocyte interaction, and they contribute to the generation of activated/memory-like CD4 and CD8 T cells in the thymus via the production of IL-4. Here, we investigated whether PLZF(+) innate T cells also affect the development and function of Foxp3(+) regulatory CD4 T cells. Flow cytometry analysis of the thymus and spleen from both CIITA transgenic C57BL/6 and wild-type BALB/c mice, which have abundant PLZF(+) CD4 T cells and invariant natural killer T cells, respectively, revealed that Foxp3(+) T cells in these mice exhibited a CD103(+) activated/memory-like phenotype. The frequency of CD103(+) regulatory T cells was considerably decreased in PLZF(+) cell-deficient CIITA(Tg)Plzf(lu/lu) and BALB/c.CD1d(-/-) mice as well as in an IL-4-deficient background, such as in CIITA(Tg)IL-4(-/-) and BALB/c.lL-4(-/-) mice, indicating that the acquisition of an activated/memory-like phenotype was dependent on PLZF(+) innate T cells and IL-4. Using fetal thymic organ culture, we further demonstrated that IL-4 in concert with TGF-β enhanced the acquisition of the activated/memory-like phenotype of regulatory T cells. In functional aspects, the activated/memory-like phenotype of Treg cells was directly related to their suppressive function; regulatory T cells of CIITA(Tg)PIV(-/-) mice more efficiently suppressed ovalbumin-induced allergic airway inflammation compared with their counterparts from wild-type mice. All of these findings suggest that PLZF(+) innate T cells also augmented the generation of activated/memory-like regulation via IL-4 production. PMID:27101876

  11. Dynamic regulation of effector IFN-γ-producing and IL-17-producing T cell subsets in the development of acute graft-versus-host disease.

    PubMed

    Zhao, Kai; Ruan, Suhong; Yin, Lingling; Zhao, Dongmei; Chen, Chong; Pan, Bin; Zeng, Lingyu; Li, Zhenyu; Xu, Kailin

    2016-02-01

    Graft-versus-host disease (GVHD) as the predominant complication of allogeneic hematopoietic stem cell transplantation remains to be fully understood. It is known that the cytokines produced by allogeneic reactive effector CD4+ and CD8+ T cells are involved in GVHD. However, the regulation and coordination of IFN-γ-producing and IL-17-producing effector T cells remain unclear. The present study aimed to investigate the dynamic changes of alloantigen-specific effector CD4+ T and CD8+ T cell subsets by flow cytometry, which produce inflammatory cytokines involved in the multistep GVHD pathogenesis progress. The results demonstrated that IL-17-producing CD8+ T (Tc17) cells and IFN-γ+CD8+ T (Tc1) cells were detected in the early stage of GVHD. The differentiation of CD4+ T cells into Th1 cell (IFN-γ+CD4+ T) and Th17 (IL-17+CD4+ T) cells was later than that of the Tc1 and Tc17 cells. The effector CD4+ T and CD8+ T cell subsets either became exhausted or became memory cells, exhibiting a CD62L-CD44+ phenotype following marked expansion during GVHD. Furthermore, T cell-associated type I (IL-2 and IFN-γ) and type II (IL-4 and IL-10) classical cytokines exhibited coordinated dynamic regulation. It was concluded that the differentiation of cytokine-producing Tc1 and Tc17 cells may be the key step in the initiation of GVHD, whereas CD4+ effector Th1 and Th17 cells are considered to be pathophysiological factors leading to the continuous aggravation of GVHD. PMID:26647759

  12. 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

  13. T cell immunodeficiency in dyskeratosis congenita.

    PubMed Central

    Lee, B W; Yap, H K; Quah, T C; Chong, A; Seah, C C

    1992-01-01

    Dyskeratosis congenita has been found to be associated with abnormal immune function. In this study we report a patient with this association. He developed Pneumocystis carinii interstitial pneumonia, and impaired cell mediated immunity was confirmed by the presence of depressed lymphoproliferative responses to in vitro stimulation with mitogen. Enumeration of T cell subsets showed a severely depressed CD4:CD8 ratio (0.38), which is the likely cause for impaired cell mediated immunity. The T cell activation pathway appeared intact, as his T lymphocytes were able to express activation markers (CD25 and HLA-DR) after mitogen stimulation. PMID:1580685

  14. Synergy between IL-15 and Id2 promotes the expansion of human NK progenitor cells, which can be counteracted by the E protein HEB required to drive T cell development.

    PubMed

    Schotte, Remko; Dontje, Wendy; Nagasawa, Maho; Yasuda, Yuko; Bakker, Arjen Q; Spits, Hergen; Blom, Bianca

    2010-06-15

    The cytokine IL-15 and the inhibitor of DNA binding (Id)2, which negatively regulates the activity of basic helix-loop-helix transcription factors, have been shown to play key roles in NK cell development. Consistent with this, exogenous IL-15 added to human thymic progenitor cells stimulated their development into NK cells at the expense of T cells both in fetal thymic organ culture and in coculture with stromal cells expressing the Notch ligand Delta-like 1. Overexpression of Id2 in thymic progenitor cells stimulated NK cell development and blocked T cell development. This, in part, is attributed to inhibition of the transcriptional activity of the E protein HEB, which we show in this study is the only E protein that enhanced T cell development. Notably, Id2 increased a pool of lineage CD1a-CD5+ progenitor cells that in synergy with IL-15 furthered expansion and differentiation into NK cells. Taken together, our findings point to a dualistic function of Id2 in controlling T/NK cell lineage decisions; T cell development is impaired by Id2, most likely by sequestering HEB, whereas NK cell development is promoted by increasing a pool of CD1a-CD5+ NK cell progenitors, which together with IL-15 differentiate into mature NK cells. PMID:20483740

  15. Production of tag-free recombinant fusion protein encompassing promiscuous T cell epitope of tetanus toxoid and dog zona pellucida glycoprotein-3 for contraceptive vaccine development.

    PubMed

    Gupta, Neha; Shrestha, Abhinav; Panda, Amulya Kumar; Gupta, Satish Kumar

    2013-07-01

    Affinity tags can interfere in various physicochemical properties and immunogenicity of the recombinant proteins. In the present study, tag-free recombinant fusion protein encompassing promiscuous T cell epitope of tetanus toxoid [TT; amino acid (aa) residues 830-844] followed by dilysine linker and dog zona pellucida glycoprotein-3 (ZP3; aa residues 23-348) (TT-KK-ZP3) was expressed in Escherichia coli. The recombinant protein, expressed as inclusion bodies (IBs), was purified by isolation of IBs, processed to remove host cell proteins, followed by solubilization and refolding. A specific 39 kDa protein including ZP3 was identified by SDS-PAGE. CD spectra showed the presence of α-helices and β-sheets, and fluorescent spectroscopy revealed emission maxima of 265 A.U. at 339 nm for refolded protein and showed red shift in the presence of 6 M guanidine hydrochloride. Immunization of inbred FvB/J female mice with purified recombinant TT-KK-ZP3 (25 μg/animal) led to generation of high antibody titers against the recombinant protein. The antibodies reacted specifically with ZP matrix surrounding mouse oocytes. Immunized mice showed significant reduction in fertility as compared to the control group. The studies described herein provide a simple method to produce and purify tag-free recombinant protein for the development of a contraceptive vaccine. PMID:23242635

  16. Inducible T-cell receptor expression in precursor T cells for leukemia control.

    PubMed

    Hoseini, S S; Hapke, M; Herbst, J; Wedekind, D; Baumann, R; Heinz, N; Schiedlmeier, B; Vignali, D A A; van den Brink, M R M; Schambach, A; Blazar, B R; Sauer, M G

    2015-07-01

    Co-transplantation of hematopoietic stem cells with those engineered to express leukemia-reactive T-cell receptors (TCRs) and differentiated ex vivo into precursor T cells (preTs) may reduce the risk of leukemia relapse. As expression of potentially self-(leukemia-) reactive TCRs will lead to negative selection or provoke autoimmunity upon thymic maturation, we investigated a novel concept whereby TCR expression set under the control of an inducible promoter would allow timely controlled TCR expression. After in vivo maturation and gene induction, preTs developed potent anti-leukemia effects. Engineered preTs provided protection even after repeated leukemia challenges by giving rise to effector and central memory cells. Importantly, adoptive transfer of TCR-transduced allogeneic preTs mediated anti-leukemia effect without evoking graft-versus-host disease (GVHD). Earlier transgene induction forced CD8(+) T-cell development was required to obtain a mature T-cell subset of targeted specificity, allowed engineered T cells to efficiently pass positive selection and abrogated the endogenous T-cell repertoire. Later induction favored CD4 differentiation and failed to produce a leukemia-reactive population emphasizing the dominant role of positive selection. Taken together, we provide new functional insights for the employment of TCR-engineered precursor cells as a controllable immunotherapeutic modality with significant anti-leukemia activity. PMID:25652739

  17. 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

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

    PubMed Central

    Knowles, D. M.

    1989-01-01

    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

  19. [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

  20. Upholding the T cell immune-regulatory function of CD31 inhibits the formation of T/B immunological synapses in vitro and attenuates the development of experimental autoimmune arthritis in vivo.

    PubMed

    Clement, Marc; Fornasa, Giulia; Loyau, Stéphane; Morvan, Marion; Andreata, Francesco; Guedj, Kevin; Khallou-Laschet, Jamila; Larghi, Paola; Le Roux, Delphine; Bismuth, Georges; Chiocchia, Gilles; Hivroz, Claire; Newman, Debra K; Nicoletti, Antonino; Caligiuri, Giuseppina

    2015-01-01

    CD31, a trans-homophilic inhibitory receptor expressed on both T- and B-lymphocytes, drives the mutual detachment of interacting leukocytes. Intriguingly, T cell CD31 molecules relocate to the immunological synapse (IS), where the T and B cells establish a stable interaction. Here, we show that intact CD31 molecules, which are able to drive an inhibitory signal, are concentrated at the periphery of the IS but are excluded from the center of the IS. At this site, were the cells establish the closest contact, the CD31 molecules are cleaved, and most of the extracellular portion of the protein, including the trans-homophilic binding sites, is shed from the cell surface. T cells lacking CD31 trans-homophilic binding sites easily establish stable interactions with B cells; at the opposite, CD31 signaling agonists inhibit T/B IS formation as well as the ensuing helper T cell activation and function. Confocal microscopy and flow cytometry analysis of experimental T/B IS shows that the T cell inhibitory effects of CD31 agonists depend on SHP-2 signaling, which reduces the phosphorylation of ZAP70. The analysis of synovial tissue biopsies from patients affected by rheumatoid arthritis showed that T cell CD31 molecules are excluded from the center of the T/B cell synapses in vivo. Interestingly, the administration of CD31 agonists in vivo significantly attenuated the development of the clinical signs of collagen-induced arthritis in DBA1/J mice. Altogether, our data indicate that the T cell co-inhibitory receptor CD31 prevents the formation of functional T/B immunological synapses and that therapeutic strategies aimed at sustaining CD31 signaling will attenuate the development of autoimmune responses in vivo. PMID:25277651

  1. B and T cell screen

    MedlinePlus

    Direct immunofluorescence; E-rosetting; T and B lymphocyte assays; B and T lymphocyte assays ... to distinguish between T and B cells. The E-rosetting test identifies T cells and direct immunofluorescence ...

  2. Nod2 Activates NF-kB in CD4+ T Cells but Its Expression Is Dispensable for T Cell-Induced Colitis

    PubMed Central

    Zanello, Galliano; Goethel, Ashleigh; Forster, Katharina; Geddes, Kaoru; Philpott, Dana J.; Croitoru, Kenneth

    2013-01-01

    Although the etiology of Crohn's disease (CD) remains elusive this disease is characterized by T cell activation that leads to chronic inflammation and mucosal damage. A potential role for maladaptation between the intestinal microbiota and the mucosal immune response is suggested by the fact that mutations in the pattern recognition receptor Nod2 are associated with higher risks for developing CD. Although Nod2 deletion in CD4+ T cells has been shown to impair the induction of colitis in the murine T cell transfer model, the analysis of T cell intrinsic Nod2 function in T cell differentiation and T cell-mediated immunity is inconsistent between several studies. In addition, the role of T cell intrinsic Nod2 in regulatory T cell (Treg) development and function during colitis remain to be analyzed. In this study, we show that Nod2 expression is higher in activated/memory CD4+ T cells and its expression was inducible after T cell receptor (TCR) ligation. Nod2 stimulation with muramyl dipeptide (MDP) led to a nuclear accumulation of c-Rel NF-kB subunit. Although functionally active in CD4+ T cells, the deletion of Nod2 did not impair the induction and the prevention of colitis in the T cell transfer model. Moreover, Nod2 deletion did not affect the development of Foxp3+ Treg cells in the spleen of recipient mice and Nod2 deficient CD4 T cells expressing the OVA specific transgenic TCR were able to differentiate in Foxp3+ Treg cells after OVA feeding. In vitro, CD25+ Nod2 deficient T cells suppressed T cell proliferation as well as wild type counter parts and T cell stimulation with MDP did not affect the proliferation and the cytokine secretion of T cells. In conclusion, our data indicate that Nod2 is functional in murine CD4+ T cells but its expression is dispensable for the T cell regulation of colitis. PMID:24324812

  3. T Cell Fates Zipped Up: How the Bach2 Basic Leucine Zipper Transcriptional Repressor Directs T Cell Differentiation and Function.

    PubMed

    Richer, Martin J; Lang, Mark L; Butler, Noah S

    2016-08-15

    Recent data illustrate a key role for the transcriptional regulator bric-a-brac, tramtrack, and broad complex and cap'n'collar homology (Bach)2 in orchestrating T cell differentiation and function. Although Bach2 has a well-described role in B cell differentiation, emerging data show that Bach2 is a prototypical member of a novel class of transcription factors that regulates transcriptional activity in T cells at super-enhancers, or regions of high transcriptional activity. Accumulating data demonstrate specific roles for Bach2 in favoring regulatory T cell generation, restraining effector T cell differentiation, and potentiating memory T cell development. Evidence suggests that Bach2 regulates various facets of T cell function by repressing other key transcriptional regulators such as B lymphocyte-induced maturation protein 1. In this review, we examine our present understanding of the role of Bach2 in T cell function and highlight the growing evidence that this transcriptional repressor functions as a key regulator involved in maintenance of T cell quiescence, T cell subset differentiation, and memory T cell generation. PMID:27496973

  4. The Lupus Susceptibility Gene Pbx1 Regulates the Balance between Follicular Helper T Cell and Regulatory T Cell Differentiation.

    PubMed

    Choi, Seung-Chul; Hutchinson, Tarun E; Titov, Anton A; Seay, Howard R; Li, Shiwu; Brusko, Todd M; Croker, Byron P; Salek-Ardakani, Shahram; Morel, Laurence

    2016-07-15

    Pbx1 controls chromatin accessibility to a large number of genes and is entirely conserved between mice and humans. The Pbx1-d dominant-negative isoform is more frequent in CD4(+) T cells from lupus patients than from healthy controls. Pbx1-d is associated with the production of autoreactive T cells in mice carrying the Sle1a1 lupus-susceptibility locus. Transgenic (Tg) expression of Pbx1-d in CD4(+) T cells reproduced the phenotypes of Sle1a1 mice, with increased inflammatory functions of CD4(+) T cells and impaired Foxp3(+) regulatory T cell (Treg) homeostasis. Pbx1-d-Tg expression also expanded the number of follicular helper T cells (TFHs) in a cell-intrinsic and Ag-specific manner, which was enhanced in recall responses and resulted in Th1-biased Abs. Moreover, Pbx1-d-Tg CD4(+) T cells upregulated the expression of miR-10a, miR-21, and miR-155, which were implicated in Treg and follicular helper T cell homeostasis. Our results suggest that Pbx1-d impacts lupus development by regulating effector T cell differentiation and promoting TFHs at the expense of Tregs. In addition, our results identify Pbx1 as a novel regulator of CD4(+) T cell effector function. PMID:27296664

  5. Transgelin-2 in B-Cells Controls T-Cell Activation by Stabilizing T Cell - B Cell Conjugates

    PubMed Central

    Chae, Myoung-Won; Kim, Hye-Ran; Kim, Chang-Hyun; Jun, Chang-Duk; Park, Zee-Yong

    2016-01-01

    The immunological synapse (IS), a dynamic and organized junction between T-cells and antigen presenting cells (APCs), is critical for initiating adaptive immunity. The actin cytoskeleton plays a major role in T-cell reorganization during IS formation, and we previously reported that transgelin-2, an actin-binding protein expressed in T-cells, stabilizes cortical F-actin, promoting T-cell activation in response to antigen stimulation. Transgelin-2 is also highly expressed in B-cells, although no specific function has been reported. In this study, we found that deficiency in transgelin-2 (TAGLN2-/-) in B-cells had little effect on B-cell development and activation, as measured by the expression of CD69, MHC class II molecules, and CD80/86. Nevertheless, in B-cells, transgelin-2 accumulated in the IS during the interaction with T-cells. These results led us to hypothesize that transgelin-2 may also be involved in IS stability in B-cells, thereby influencing T-cell function. Notably, we found that transgelin-2 deficiency in B-cells reduced T-cell activation, as determined by the release of IL-2 and interferon-γ and the expression of CD69. Furthermore, the reduced T-cell activation was correlated with reduced B-cell–T-cell conjugate formation. Collectively, these results suggest that actin stability in B-cells during IS formation is critical for the initiation of adaptive T-cell immunity. PMID:27232882

  6. Discrete dynamic modeling of T cell survival signaling networks

    NASA Astrophysics Data System (ADS)

    Zhang, Ranran

    2009-03-01

    Biochemistry-based frameworks are often not applicable for the modeling of heterogeneous regulatory systems that are sparsely documented in terms of quantitative information. As an alternative, qualitative models assuming a small set of discrete states are gaining acceptance. This talk will present a discrete dynamic model of the signaling network responsible for the survival and long-term competence of cytotoxic T cells in the blood cancer T-LGL leukemia. We integrated the signaling pathways involved in normal T cell activation and the known deregulations of survival signaling in leukemic T-LGL, and formulated the regulation of each network element as a Boolean (logic) rule. Our model suggests that the persistence of two signals is sufficient to reproduce all known deregulations in leukemic T-LGL. It also indicates the nodes whose inactivity is necessary and sufficient for the reversal of the T-LGL state. We have experimentally validated several model predictions, including: (i) Inhibiting PDGF signaling induces apoptosis in leukemic T-LGL. (ii) Sphingosine kinase 1 and NFκB are essential for the long-term survival of T cells in T-LGL leukemia. (iii) T box expressed in T cells (T-bet) is constitutively activated in the T-LGL state. The model has identified potential therapeutic targets for T-LGL leukemia and can be used for generating long-term competent CTL necessary for tumor and cancer vaccine development. The success of this model, and of other discrete dynamic models, suggests that the organization of signaling networks has an determining role in their dynamics. Reference: R. Zhang, M. V. Shah, J. Yang, S. B. Nyland, X. Liu, J. K. Yun, R. Albert, T. P. Loughran, Jr., Network Model of Survival Signaling in LGL Leukemia, PNAS 105, 16308-16313 (2008).

  7. mTORC1 in Thymic Epithelial Cells Is Critical for Thymopoiesis, T-Cell Generation, and Temporal Control of γδT17 Development and TCRγ/δ Recombination.

    PubMed

    Wang, Hong-Xia; Shin, Jinwook; Wang, Shang; Gorentla, Balachandra; Lin, Xingguang; Gao, Jimin; Qiu, Yu-Rong; Zhong, Xiao-Ping

    2016-02-01

    Thymus is crucial for generation of a diverse repertoire of T cells essential for adaptive immunity. Although thymic epithelial cells (TECs) are crucial for thymopoiesis and T cell generation, how TEC development and function are controlled is poorly understood. We report here that mTOR complex 1 (mTORC1) in TECs plays critical roles in thymopoiesis and thymus function. Acute deletion of mTORC1 in adult mice caused severe thymic involution. TEC-specific deficiency of mTORC1 (mTORC1KO) impaired TEC maturation and function such as decreased expression of thymotropic chemokines, decreased medullary TEC to cortical TEC ratios, and altered thymic architecture, leading to severe thymic atrophy, reduced recruitment of early thymic progenitors, and impaired development of virtually all T-cell lineages. Strikingly, temporal control of IL-17-producing γδT (γδT17) cell differentiation and TCRVγ/δ recombination in fetal thymus is lost in mTORC1KO thymus, leading to elevated γδT17 differentiation and rearranging of fetal specific TCRVγ/δ in adulthood. Thus, mTORC1 is central for TEC development/function and establishment of thymic environment for proper T cell development, and modulating mTORC1 activity can be a strategy for preventing thymic involution/atrophy. PMID:26889835

  8. mTORC1 in Thymic Epithelial Cells Is Critical for Thymopoiesis, T-Cell Generation, and Temporal Control of γδT17 Development and TCRγ/δ Recombination

    PubMed Central

    Wang, Hong-Xia; Shin, Jinwook; Wang, Shang; Gorentla, Balachandra; Lin, Xingguang; Gao, Jimin; Qiu, Yu-Rong; Zhong, Xiao-Ping

    2016-01-01

    Thymus is crucial for generation of a diverse repertoire of T cells essential for adaptive immunity. Although thymic epithelial cells (TECs) are crucial for thymopoiesis and T cell generation, how TEC development and function are controlled is poorly understood. We report here that mTOR complex 1 (mTORC1) in TECs plays critical roles in thymopoiesis and thymus function. Acute deletion of mTORC1 in adult mice caused severe thymic involution. TEC-specific deficiency of mTORC1 (mTORC1KO) impaired TEC maturation and function such as decreased expression of thymotropic chemokines, decreased medullary TEC to cortical TEC ratios, and altered thymic architecture, leading to severe thymic atrophy, reduced recruitment of early thymic progenitors, and impaired development of virtually all T-cell lineages. Strikingly, temporal control of IL-17-producing γδT (γδT17) cell differentiation and TCRVγ/δ recombination in fetal thymus is lost in mTORC1KO thymus, leading to elevated γδT17 differentiation and rearranging of fetal specific TCRVγ/δ in adulthood. Thus, mTORC1 is central for TEC development/function and establishment of thymic environment for proper T cell development, and modulating mTORC1 activity can be a strategy for preventing thymic involution/atrophy. PMID:26889835

  9. Biomarkers in T cell therapy clinical trials

    PubMed Central

    2011-01-01

    T cell therapy represents an emerging and promising modality for the treatment of both infectious disease and cancer. Data from recent clinical trials have highlighted the potential for this therapeutic modality to effect potent anti-tumor activity. Biomarkers, operationally defined as biological parameters measured from patients that provide information about treatment impact, play a central role in the development of novel therapeutic agents. In the absence of information about primary clinical endpoints, biomarkers can provide critical insights that allow investigators to guide the clinical development of the candidate product. In the context of cell therapy trials, the definition of biomarkers can be extended to include a description of parameters of the cell product that are important for product bioactivity. This review will focus on biomarker studies as they relate to T cell therapy trials, and more specifically: i. An overview and description of categories and classes of biomarkers that are specifically relevant to T cell therapy trials, and ii. Insights into future directions and challenges for the appropriate development of biomarkers to evaluate both product bioactivity and treatment efficacy of T cell therapy trials. PMID:21851646

  10. Studies on thyroglobulin-specific suppressor T cell function in autoimmune thyroid disease

    SciTech Connect

    Mori, H.; Hamada, N.; DeGroot, L.J.

    1985-08-01

    T cell regulation of the generation of thyroglobulin plaque-forming cells (Tg PFC) and protein A plaque-forming cells (Prot A PFC) was investigated using lymphocytes from patients with autoimmune thyroid disease. T and B cell mixed cultures (T-B MC) were carried out without mitogenic or antigenic stimulation to identify physiological T cell effects in the system. Tg PFC were found in 8 (44%) of 18 patients who had high titers of thyroglobulin antibody in their sera. Tg-specific and nonspecific immunoregulation by T cells from patients and normal subjects was studied using B cells from these eight patients in the T-B MC system. Remarkably lower values of Tg PFC induction compared to Prot A PFC induction were found after T cell addition. Normal T cells inhibited Tg PFC induction, but patient T cells did not, while the same extent of helper effects were found on Prot A PFC induction by the addition of patient and normal T cells. Irradiation (1500 rads) of T cells from patients and normal subjects significantly enhanced both Tg PFC and Prot A PFC induction. Thus, Tg-specific suppressor T cells are present in all normal subjects as part of the radiosensitive suppressor T cell subset. The increase in Tg-PFC caused by irradiation-induced inhibition of Tg-specific suppressor T cell function was significantly greater in normal subjects than in patients. Histamine type 2 receptor-bearing T cells inhibited Prot A PFC induction, but not Tg PFC induction, in the autologous T-B MC system. No Tg PFC were induced from normal B cells in any combination with untreated T cells, irradiated T cells, or histamine type 2 receptor-negative T cells from patients or normal subjects.

  11. Engineered T cells: the promise and challenges of cancer immunotherapy.

    PubMed

    Fesnak, Andrew D; June, Carl H; Levine, Bruce L

    2016-08-23

    The immune system evolved to distinguish non-self from self to protect the organism. As cancer is derived from our own cells, immune responses to dysregulated cell growth present a unique challenge. This is compounded by mechanisms of immune evasion and immunosuppression that develop in the tumour microenvironment. The modern genetic toolbox enables the adoptive transfer of engineered T cells to create enhanced anticancer immune functions where natural cancer-specific immune responses have failed. Genetically engineered T cells, so-called 'living drugs', represent a new paradigm in anticancer therapy. Recent clinical trials using T cells engineered to express chimeric antigen receptors (CARs) or engineered T cell receptors (TCRs) have produced stunning results in patients with relapsed or refractory haematological malignancies. In this Review we describe some of the most recent and promising advances in engineered T cell therapy with a particular emphasis on what the next generation of T cell therapy is likely to entail. PMID:27550819

  12. Chimeric Antigen Receptors Modified T-Cells for Cancer Therapy

    PubMed Central

    Dai, Hanren; Wang, Yao; Lu, Xuechun

    2016-01-01

    The genetic modification and characterization of T-cells with chimeric antigen receptors (CARs) allow functionally distinct T-cell subsets to recognize specific tumor cells. The incorporation of costimulatory molecules or cytokines can enable engineered T-cells to eliminate tumor cells. CARs are generated by fusing the antigen-binding region of a monoclonal antibody (mAb) or other ligand to membrane-spanning and intracellular-signaling domains. They have recently shown clinical benefit in patients treated with CD19-directed autologous T-cells. Recent successes suggest that the modification of T-cells with CARs could be a powerful approach for developing safe and effective cancer therapeutics. Here, we briefly review early studies, consider strategies to improve the therapeutic potential and safety, and discuss the challenges and future prospects for CAR T-cells in cancer therapy. PMID:26819347

  13. Chimeric Antigen Receptors Modified T-Cells for Cancer Therapy.

    PubMed

    Dai, Hanren; Wang, Yao; Lu, Xuechun; Han, Weidong

    2016-07-01

    The genetic modification and characterization of T-cells with chimeric antigen receptors (CARs) allow functionally distinct T-cell subsets to recognize specific tumor cells. The incorporation of costimulatory molecules or cytokines can enable engineered T-cells to eliminate tumor cells. CARs are generated by fusing the antigen-binding region of a monoclonal antibody (mAb) or other ligand to membrane-spanning and intracellular-signaling domains. They have recently shown clinical benefit in patients treated with CD19-directed autologous T-cells. Recent successes suggest that the modification of T-cells with CARs could be a powerful approach for developing safe and effective cancer therapeutics. Here, we briefly review early studies, consider strategies to improve the therapeutic potential and safety, and discuss the challenges and future prospects for CAR T-cells in cancer therapy. PMID:26819347

  14. Chimeric Antigen Receptors Modified T-Cells for Cancer Therapy

    PubMed Central

    Dai, Hanren; Wang, Yao; Lu, Xuechun

    2016-01-01

    The genetic modification and characterization of T-cells with chimeric antigen receptors (CARs) allow functionally distinct T-cell subsets to recognize specific tumor cells. The incorporation of costimulatory molecules or cytokines can enable engineered T-cells to eliminate tumor cells. CARs are generated by fusing the antigen-binding region of a monoclonal antibody (mAb) or other ligand to membrane-spanning and intracellular-signaling domains. They have recently shown clinical benefit in patients treated with CD19-directed autologous T-cells. Recent successes suggest that the modification of T-cells with CARs could be a powerful approach for developing safe and effective cancer therapeutics. Here, we briefly review early studies, consider strategies to improve the therapeutic potential and safety, and discuss the challenges and future prospects for CAR T-cells in cancer therapy.

  15. Regulatory T cells: regulators of life.

    PubMed

    Schumacher, Anne; Zenclussen, Ana Claudia

    2014-08-01

    Pregnancy still represents one of the most fascinating paradoxical phenomena in science. Immediately after conception, the maternal immune system is challenged by the presence of foreign paternal antigens in the semen. This triggers mechanisms of recognition and tolerance that all together allow the embryo to implant and later the fetus to develop. Tolerance mechanisms to maintain pregnancy are of special interest as they defy the classical immunology rules. Several cell types, soluble factors, and immune regulatory molecules have been proposed to contribute to fetal tolerance. Within these, regulatory T cells (Treg) are one of the most studied immune cell populations lately. They are reportedly involved in fetal acceptance. Here, we summarize several aspects of Treg biology in normal and pathologic pregnancies focusing on Treg frequencies, subtypes, antigen specificity, and activity as well as on factors influencing Treg generation, recruitment, and function. This review also highlights the contribution of fetal Treg in tolerance induction and addresses the role of Treg in autoimmune diseases and infections during gestation. Finally, the potential of Treg as a predictive marker for the success of assisted reproductive techniques and for therapeutic interventions is discussed. PMID:24661545

  16. 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

  17. T cells as a therapeutic target in SLE

    PubMed Central

    Comte, Denis; Karampetsou, Maria P.; Tsokos, George C.

    2014-01-01

    Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease characterized by a loss of tolerance to multiple endogenous antigens. SLE etiology remains largely unknown, despite recent insight into the immunopathogenesis of the disease. T cells are important in the development of the disease by amplifying the immune response and contributing to organ damage. Aberrant signaling, cytokine secretion and tissue homing displayed by SLE T cells have been extensively studied and the underlying pathogenic molecular mechanisms are starting to be elucidated. T-cell targeted treatments are being explored in SLE patients. This review is an update on the T-cell abnormalities and related therapeutic options in SLE. PMID:25801878

  18. Novel treatments for T-cell lymphoma.

    PubMed

    Cheah, Chan Yoon; Oki, Yasuhiro; Fanale, Michelle A

    2015-01-01

    T-cell lymphomas are a biologically and clinically diverse collection of diseases that collectively account for 10% to 15% of non-Hodgkin lymphomas. Unlike B-cell lymphomas, the response of T-cell lymphomas to standard anthracycline-containing chemotherapy regimens is suboptimal and the prognosis of patients is accordingly poor. To address these shortcomings, there has been a proliferation in biologic agents with novel mechanisms of action that target surface antigens, signaling pathways, or cellular processes. Given the large number of candidate molecules showing preclinical promise and the rarity of these diseases, drug development for peripheral T-cell lymphoma is challenging. We provide an overview of agents that have recently been approved for relapsed/refractory T-cell lymphoma and highlight efforts to introduce these agents into front-line treatment protocols in combination with chemotherapy. We discuss biologic doublets currently being evaluated as "chemotherapy-free" salvage regimens and highlight some of the most promising investigational agents in early clinical development. PMID:25993211

  19. Depressed immune surveillance against cancer: role of deficient T cell: extracellular matrix interactions.

    PubMed

    Górski, A; Castronovo, V; Stepień-Sopniewska, B; Grieb, P; Ryba, M; Mrowiec, T; Korczak-Kowalska, G; Wierzbicki, P; Matysiak, W; Dybowska, B

    1994-07-01

    Although T cells infiltrate malignant tumors, the local immune response is usually inefficient and tumors escape destruction. While extracellular matrix proteins strongly costimulate T cell responses in normal individuals, our studies indicate that peripheral blood T cells from cancer patients and tumor infiltrating cells respond poorly or are resistant to stimulative signals mediated by collagen I and IV and fibronectin. Moreover, the adhesive properties of cancer T cells are markedly depressed. Those functional deficiencies are paralleled by variable deficits in integrin and non-integrin T cell receptors for extracellular matrix. Immunotherapy with BCG causes a dramatic but transient increase in T cell: ECM interactions. PMID:7827959

  20. The development of autoimmune features in aging mice is closely associated with alterations of the peripheral CD4⁺ T-cell compartment.

    PubMed

    Nusser, Anja; Nuber, Natko; Wirz, Oliver F; Rolink, Hannie; Andersson, Jan; Rolink, Antonius

    2014-10-01

    Some signs of potential autoimmunity, such as the appearance of antinuclear antibodies (ANAs) become prevalent with age. In most cases, elderly people with ANAs remain healthy. Here, we investigated whether the same holds true for inbred strains of mice. Indeed, we show that most mice of the C57BL/6 (B6) strain spontaneously produced IgG ANA at 8-12 months of age, showed IgM deposition in kidneys and lymphocyte infiltrates in submandibular salivary glands. Despite all of this, the mice remained healthy. ANA production is likely CD4(+) T-cell dependent, since old (40-50 weeks of age) B6 mice deficient for MHC class II do not produce IgG ANAs. BM chimeras showed that ANA production was not determined by age-related changes in radiosensitive, hematopoietic progenitor cells, and that the CD4(+) T cells that promote ANA production were radioresistant. Thymectomy of B6 mice at 5 weeks of age led to premature alterations in T-cell homeostasis and ANA production, by 15 weeks of age, similar to that in old mice. Our findings suggest that a disturbed T-cell homeostasis may drive the onset of some autoimmune features. PMID:25044476

  1. Monoclonal regulatory T cells provide insights into T cell suppression

    PubMed Central

    Gubser, Céline; Schmaler, Mathias; Rossi, Simona W.; Palmer, Ed

    2016-01-01

    Regulatory T cells (Tregs) have a crucial role in maintaining lymphocyte homeostasis. However an understanding of how Tregs function at a cellular and molecular level has not yet been fully elucidated. Here, we make use of a T cell receptor (TCR) transgenic, Rag−/− mouse expressing a Forkhead-Box-Protein P3 (Foxp3) transgene. This mouse provides a source of monoclonal CD4+ Foxp3+ T cells with a defined specificity. Here we show that monoclonal B3K506 Tregs are functional in vitro and in vivo and clearly require cognate antigen to be suppressive. We further show that the strength of Treg stimulation determines the strength of Treg mediated suppression. Finally we analysed various suppressive mechanisms used by monoclonal Tregs and found that Treg-Tconv proximity is a parameter, which correlates with enhanced suppression. PMID:27210828

  2. Monoclonal regulatory T cells provide insights into T cell suppression.

    PubMed

    Gubser, Céline; Schmaler, Mathias; Rossi, Simona W; Palmer, Ed

    2016-01-01

    Regulatory T cells (Tregs) have a crucial role in maintaining lymphocyte homeostasis. However an understanding of how Tregs function at a cellular and molecular level has not yet been fully elucidated. Here, we make use of a T cell receptor (TCR) transgenic, Rag(-/-) mouse expressing a Forkhead-Box-Protein P3 (Foxp3) transgene. This mouse provides a source of monoclonal CD4(+) Foxp3(+) T cells with a defined specificity. Here we show that monoclonal B3K506 Tregs are functional in vitro and in vivo and clearly require cognate antigen to be suppressive. We further show that the strength of Treg stimulation determines the strength of Treg mediated suppression. Finally we analysed various suppressive mechanisms used by monoclonal Tregs and found that Treg-Tconv proximity is a parameter, which correlates with enhanced suppression. PMID:27210828

  3. Isolation and Characterization of Salmonid CD4+ T Cells.

    PubMed

    Maisey, Kevin; Montero, Ruth; Corripio-Miyar, Yolanda; Toro-Ascuy, Daniela; Valenzuela, Beatriz; Reyes-Cerpa, Sebastián; Sandino, Ana María; Zou, Jun; Wang, Tiehui; Secombes, Christopher J; Imarai, Mónica

    2016-05-15

    This study reports the isolation and functional characterization of rainbow trout (Oncorhynchus mykiss) CD4-1(+) T cells and the establishment of an IL-15-dependent CD4-1(+) T cell line. By using Abs specific for CD4-1 and CD3ε it was possible to isolate the double-positive T cells in spleen and head kidney. The morphology and the presence of transcripts for T cell markers in the sorted CD4-1(+)CD3ε(+) cells were studied next. Cells were found to express TCRα, TCRβ, CD152 (CTLA-4), CD154 (CD40L), T-bet, GATA-3, and STAT-1. The sorted CD4-1(+) T cells also had a distinctive functional attribute of mammalian T lymphocytes, namely they could undergo Ag-specific proliferation, using OVA as a model Ag. The OVA-stimulated cells showed increased expression of several cytokines, including IFN-γ1, IL-4/13A, IL-15, IL-17D, IL-10, and TGF-β1, perhaps indicating that T cell proliferation led to differentiation into distinct effector phenotypes. Using IL-15 as a growth factor, we have selected a lymphoid cell line derived from rainbow trout head kidney cells. The morphology, cell surface expression of CD4-1, and the presence of transcripts of T cell cytokines and transcription factors indicated that this is a CD4-1(+) T cell line. To our knowledge, this is the first demonstration of the presence of CD4-1(+)CD3ε(+) T cells in salmonids. As in mammals, CD4-1(+) T cells may be the master regulators of immune responses in fish, and therefore these findings and the new model T cell line developed will contribute to a greater understanding of T cell function and immune responses in teleost fish. PMID:27053758

  4. Producer T cells: Using genetically engineered T cells as vehicles to generate and deliver therapeutics to tumors

    PubMed Central

    Tsai, Alexander K.; Davila, Eduardo

    2016-01-01

    ABSTRACT Adoptive cell transfer (ACT) is an emerging anticancer therapy that has shown promise in various malignancies. Redirecting antigen specificity by genetically engineering T cells to stably express receptors has become an effective variant of ACT. A novel extension of this approach is to utilize engineered T cells to produce and deliver anticancer therapeutics that enhance cytotoxic T cell function and simultaneously inhibit immunosuppressive processes. Here, we review the potential of using T cells as therapeutic-secreting vehicles for immunotherapies and present theoretical and established arguments in support of further development of this unique cell-based immunotherapy.

  5. HEB-deficient T-cell precursors lose T-cell potential and adopt an alternative pathway of differentiation.

    PubMed

    Braunstein, Marsela; Anderson, Michele K

    2011-03-01

    Early thymocytes possess multilineage potential, which is progressively restricted as cells transit through the double-negative stages of T-cell development. DN1 cells retain the ability to become natural killer cells, dendritic cells, B cells, and myeloid cells as well as T cells, but these options are lost by the DN3 stage. The Notch1 signaling pathway is indispensable for initiation of the T-cell lineage and inhibitory for the B-cell lineage, but the regulatory mechanisms by which the T-cell fate is locked in are largely undefined. Previously, we discovered that the E-protein transcription factor HEBAlt promoted T-cell specification. Here, we report that HEB(-/-) T-cell precursors have compromised Notch1 function and lose T-cell potential. Moreover, reconstituting HEB(-/-) precursors with Notch1 activity enforced fidelity to the T-cell fate. However, instead of becoming B cells, HEB(-/-) DN3 cells adopted a DN1-like phenotype and could be induced to differentiate into thymic NK cells. HEB(-/-) DN1-like cells retained GATA3 and Id2 expression but had lower levels of the Bcl11b gene, a Notch target gene. Therefore, our studies have revealed a new set of interactions between HEB, Notch1, and GATA3 that regulate the T-cell fate choice in developing thymocytes. PMID:21189289

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

    PubMed Central

    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. DOI: http://dx.doi.org/10.7554/eLife.03468.001 PMID:25182415

  7. Studies of T-cell activation in chronic inflammation

    PubMed Central

    2002-01-01

    Chapter summary The strong association between specific alleles encoded within the MHC class II region and the development of rheumatoid arthritis (RA) has provided the best evidence to date that CD4+ T cells play a role in the pathogenesis of this chronic inflammatory disease. However, the unusual phenotype of synovial T cells, including their profound proliferative hyporesponsiveness to TCR ligation, has challenged the notion that T-cell effector responses are driven by cognate cartilage antigens in inflamed synovial joints. The hierarchy of T-cell dysfunction from peripheral blood to inflamed joint suggests that these defects are acquired through prolonged exposure to proinflammatory cytokines such as tumour necrosis factor (TNF)-α. Indeed, there are now compelling data to suggest that chronic cytokine activation may contribute substantially to the phenotype and effector function of synovial T cells. Studies reveal that chronic exposure of T cells to TNF uncouples TCR signal transduction pathways by impairing the assembly and stability of the TCR/CD3 complex at the cell surface. Despite this membrane-proximal effect, TNF selectively uncouples downstream signalling pathways, as is shown by the dramatic suppression of calcium signalling responses, while Ras/ERK activation is spared. On the basis of these data, it is proposed that T-cell survival and effector responses are driven by antigen-independent, cytokine-dependent mechanisms, and that therapeutic strategies that seek to restore T-cell homeostasis rather than further depress T-cell function should be explored in the future. PMID:12110140

  8. TIM3 Mediates T Cell Exhaustion during Mycobacterium tuberculosis Infection

    PubMed Central

    Jayaraman, Pushpa; Jacques, Miye K.; Zhu, Chen; Steblenko, Katherine M.; Stowell, Britni L.; Madi, Asaf; Anderson, Ana C.; Kuchroo, Vijay K.; Behar, Samuel M.

    2016-01-01

    While T cell immunity initially limits Mycobacterium tuberculosis infection, why T cell immunity fails to sterilize the infection and allows recrudescence is not clear. One hypothesis is that T cell exhaustion impairs immunity and is detrimental to the outcome of M. tuberculosis infection. Here we provide functional evidence for the development T cell exhaustion during chronic TB. Second, we evaluate the role of the inhibitory receptor T cell immunoglobulin and mucin domain–containing-3 (TIM3) during chronic M. tuberculosis infection. We find that TIM3 expressing T cells accumulate during chronic infection, co-express other inhibitory receptors including PD1, produce less IL-2 and TNF but more IL-10, and are functionally exhausted. Finally, we show that TIM3 blockade restores T cell function and improves bacterial control, particularly in chronically infected susceptible mice. These data show that T cell immunity is suboptimal during chronic M. tuberculosis infection due to T cell exhaustion. Moreover, in chronically infected mice, treatment with anti-TIM3 mAb is an effective therapeutic strategy against tuberculosis. PMID:26967901

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

    MedlinePlus

    ... Normal? What’s Not? Page Content 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 ...

  10. Fidelity of a BAC-EGFP transgene in reporting dynamic expression of IL-7Rα in T cells

    PubMed Central

    Yu, Shuyang; Zhou, Xinyuan; Hsiao, Jordy J.; Yu, Dahai; Saunders, Thomas L.; Xue, Hai-Hui

    2014-01-01

    Interleukin-7 receptor α chain (IL-7Rα)-derived signals are critical for normal T cell development, mature T cell homeostasis, and longevity of memory T cells. IL-7Rα expression in T cells is dynamically regulated at different developmental and antigen-responding stages. However, the molecular mechanism underlying the dynamic regulation is not completely understood. Here we describe generation of a bacterial artificial chromosome (BAC)-based reporter transgenic mouse strain, which contains 210 kb DNA sequence flanking the Il7r locus. We used in vitro validated EGFP reporter and insulator sequences to facilitate the reporter transgene expression. Consistent with endogenous IL-7Rα expression, the BAC transgene was expressed in mature T cells, a portion of natural killer cells but not in mature B cells. In the thymus, the EGFP reporter and endogenous IL-7Rα showed synchronized silencing in CD4+CD8+ double positive stage, were both upregulated in CD4+ or CD8+ single positive thymocytes, and both continued to be co-expressed in naïve T cells in the periphery. Upon encountering antigen, the antigen-specific effector CD8+ T cells downregulated both endogenous IL-7Rα and the EGFP reporter, which were upregulated in synchrony in antigen-specific memory CD8 T cells. These results indicate that the BAC-EGFP transgene reports endogenous IL-7Rα regulation with high fidelity, and further suggest that the 210 kb sequence flanking the Il7r locus contains sufficient genetic information to regulate its expression changes in T lineage cells. Our approach thus represents a critical initial step towards systematic dissection of the cis regulatory elements controlling dynamic IL-7Rα regulation during T cell development and cellular immune responses. PMID:21533667

  11. T cell responses to cytomegalovirus.

    PubMed

    Klenerman, Paul; Oxenius, Annette

    2016-06-01

    Human cytomegalovirus (HCMV) establishes a latent infection that generally remains asymptomatic in immune-competent hosts for decades but can cause serious illness in immune-compromised individuals. The long-term control of CMV requires considerable effort from the host immune system and has a lasting impact on the profile of the immune system. One hallmark of CMV infection is the maintenance of large populations of CMV-specific memory CD8(+) T cells - a phenomenon termed memory inflation - and emerging data suggest that memory inflation is associated with impaired immunity in the elderly. In this Review, we discuss the molecular triggers that promote memory inflation, the idea that memory inflation could be considered a natural pathway of T cell maturation that could be harnessed in vaccination, and the broader implications of CMV infection and the T cell responses it elicits. PMID:27108521

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

    SciTech Connect

    Doi, Keiko; Fujimoto, Takahiro; Okamura, Tadashi; Ogawa, Masahiro; Tanaka, Yoko; Mototani, Yasumasa; Goto, Motohito; Ota, Takeharu; Matsuzaki, Hiroshi; Kuroki, Masahide; Tsunoda, Toshiyuki; Sasazuki, Takehiko; Shirasawa, Senji

    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.

  13. Activity of host-derived T cells which differentiate in nude mice grafted with co-isogenic or allogeneic thymuses.

    PubMed

    Kindred, B; Loor, F

    1974-05-01

    If nude mice are grafted with a neonatal thymus, host type precursor cells develop within the graft thymus and after about 6 wk the T-cell population of the thymus, spleen, and lymph nodes is of host type. However, immunological responsiveness produced in nude mice in this manner is incomplete: (a) the ability to react to T-cell mitogens in vitro is greater than in untreated nudes but lower than in normal mice; (b) the response to T-cell dependent antigens is less than normal; and (c) the rejection of skin grafts is slower than in normal animals. Whether host precursor cells which differentiate in an allogeneic thymus are able to reject skin grafts from thymus donor strain appears to depend on the strain combination used. PMID:4596513

  14. T-cell libraries allow simple parallel generation of multiple peptide-specific human T-cell clones.

    PubMed

    Theaker, Sarah M; Rius, Cristina; Greenshields-Watson, Alexander; Lloyd, Angharad; Trimby, Andrew; Fuller, Anna; Miles, John J; Cole, David K; Peakman, Mark; Sewell, Andrew K; Dolton, Garry

    2016-03-01

    Isolation of peptide-specific T-cell clones is highly desirable for determining the role of T-cells in human disease, as well as for the development of therapies and diagnostics. However, generation of monoclonal T-cells with the required specificity is challenging and time-consuming. Here we describe a library-based strategy for the simple parallel detection and isolation of multiple peptide-specific human T-cell clones from CD8(+) or CD4(+) polyclonal T-cell populations. T-cells were first amplified by CD3/CD28 microbeads in a 96U-well library format, prior to screening for desired peptide recognition. T-cells from peptide-reactive wells were then subjected to cytokine-mediated enrichment followed by single-cell cloning, with the entire process from sample to validated clone taking as little as 6 weeks. Overall, T-cell libraries represent an efficient and relatively rapid tool for the generation of peptide-specific T-cell clones, with applications shown here in infectious disease (Epstein-Barr virus, influenza A, and Ebola virus), autoimmunity (type 1 diabetes) and cancer. PMID:26826277

  15. T-cell libraries allow simple parallel generation of multiple peptide-specific human T-cell clones

    PubMed Central

    Theaker, Sarah M.; Rius, Cristina; Greenshields-Watson, Alexander; Lloyd, Angharad; Trimby, Andrew; Fuller, Anna; Miles, John J.; Cole, David K.; Peakman, Mark; Sewell, Andrew K.; Dolton, Garry

    2016-01-01

    Isolation of peptide-specific T-cell clones is highly desirable for determining the role of T-cells in human disease, as well as for the development of therapies and diagnostics. However, generation of monoclonal T-cells with the required specificity is challenging and time-consuming. Here we describe a library-based strategy for the simple parallel detection and isolation of multiple peptide-specific human T-cell clones from CD8+ or CD4+ polyclonal T-cell populations. T-cells were first amplified by CD3/CD28 microbeads in a 96U-well library format, prior to screening for desired peptide recognition. T-cells from peptide-reactive wells were then subjected to cytokine-mediated enrichment followed by single-cell cloning, with the entire process from sample to validated clone taking as little as 6 weeks. Overall, T-cell libraries represent an efficient and relatively rapid tool for the generation of peptide-specific T-cell clones, with applications shown here in infectious disease (Epstein–Barr virus, influenza A, and Ebola virus), autoimmunity (type 1 diabetes) and cancer. PMID:26826277

  16. 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

  17. Switching CAR T cells on and off: a novel modular platform for retargeting of T cells to AML blasts.

    PubMed

    Cartellieri, M; Feldmann, A; Koristka, S; Arndt, C; Loff, S; Ehninger, A; von Bonin, M; Bejestani, E P; Ehninger, G; Bachmann, M P

    2016-01-01

    The adoptive transfer of CD19-specific chimeric antigen receptor engineered T cells (CAR T cells) resulted in encouraging clinical trials in indolent B-cell malignancies. However, they also show the limitations of this fascinating technology: CAR T cells can lead to even life-threatening off-tumor, on-target side effects if CAR T cells crossreact with healthy tissues. Here, we describe a novel modular universal CAR platform technology termed UniCAR that reduces the risk of on-target side effects by a rapid and reversible control of CAR T-cell reactivity. The UniCAR system consists of two components: (1) a CAR for an inert manipulation of T cells and (2) specific targeting modules (TMs) for redirecting UniCAR T cells in an individualized time- and target-dependent manner. UniCAR T cells can be armed against different tumor targets simply by replacement of the respective TM for (1) targeting more than one antigen simultaneously or subsequently to enhance efficacy and (2) reducing the risk for development of antigen-loss tumor variants under treatment. Here we provide 'proof of concept' for retargeting of UniCAR T cells to CD33- and/or CD123-positive acute myeloid leukemia blasts in vitro and in vivo. PMID:27518241

  18. Force Generation upon T Cell Receptor Engagement

    PubMed Central

    Husson, Julien; Chemin, Karine; Bohineust, Armelle; Hivroz, Claire; Henry, Nelly

    2011-01-01

    T cells are major players of adaptive immune response in mammals. Recognition of an antigenic peptide in association with the major histocompatibility complex at the surface of an antigen presenting cell (APC) is a specific and sensitive process whose mechanism is not fully understood. The potential contribution of mechanical forces in the T cell activation process is increasingly debated, although these forces are scarcely defined and hold only limited experimental evidence. In this work, we have implemented a biomembrane force probe (BFP) setup and a model APC to explore the nature and the characteristics of the mechanical forces potentially generated upon engagement of the T cell receptor (TCR) and/or lymphocyte function-associated antigen-1 (LFA-1). We show that upon contact with a model APC coated with antibodies towards TCR-CD3, after a short latency, the T cell developed a timed sequence of pushing and pulling forces against its target. These processes were defined by their initial constant growth velocity and loading rate (force increase per unit of time). LFA-1 engagement together with TCR-CD3 reduced the growing speed during the pushing phase without triggering the same mechanical behavior when engaged alone. Intracellular Ca2+ concentration ([Ca2+]i) was monitored simultaneously to verify the cell commitment in the activation process. [Ca2+]i increased a few tens of seconds after the beginning of the pushing phase although no strong correlation appeared between the two events. The pushing phase was driven by actin polymerization. Tuning the BFP mechanical properties, we could show that the loading rate during the pulling phase increased with the target stiffness. This indicated that a mechanosensing mechanism is implemented in the early steps of the activation process. We provide here the first quantified description of force generation sequence upon local bidimensional engagement of TCR-CD3 and discuss its potential role in a T cell mechanically

  19. 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

  20. Intestinal Barrier Dysfunction Develops at the Onset of Experimental Autoimmune Encephalomyelitis, and Can Be Induced by Adoptive Transfer of Auto-Reactive T Cells

    PubMed Central

    Nouri, Mehrnaz; Bredberg, Anders; Weström, Björn; Lavasani, Shahram

    2014-01-01

    Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system with a pathogenesis involving a dysfunctional blood-brain barrier and myelin-specific, autoreactive T cells. Although the commensal microbiota seems to affect its pathogenesis, regulation of the interactions between luminal antigens and mucosal immune elements remains unclear. Herein, we investigated whether the intestinal mucosal barrier is also targeted in this disease. Experimental autoimmune encephalomyelitis (EAE), the prototypic animal model of MS, was induced either by active immunization or by adoptive transfer of autoreactive T cells isolated from these mice. We show increased intestinal permeability, overexpression of the tight junction protein zonulin and alterations in intestinal morphology (increased crypt depth and thickness of the submucosa and muscularis layers). These intestinal manifestations were seen at 7 days (i.e., preceding the onset of neurological symptoms) and at 14 days (i.e., at the stage of paralysis) after immunization. We also demonstrate an increased infiltration of proinflammatory Th1/Th17 cells and a reduced regulatory T cell number in the gut lamina propria, Peyer's patches and mesenteric lymph nodes. Adoptive transfer to healthy mice of encephalitogenic T cells, isolated from EAE-diseased animals, led to intestinal changes similar to those resulting from the immunization procedure. Our findings show that disruption of intestinal homeostasis is an early and immune-mediated event in EAE. We propose that this intestinal dysfunction may act to support disease progression, and thus represent a potential therapeutic target in MS. In particular, an increased understanding of the regulation of tight junctions at the blood-brain barrier and in the intestinal wall may be crucial for design of future innovative therapies. PMID:25184418

  1. Anti-thymocyte globulin (ATG) differentially depletes naïve and memory T cells and permits memory-type regulatory T cells in nonobese diabetic mice

    PubMed Central

    2012-01-01

    Background ATG has been employed to deplete T cells in several immune-mediated conditions. However, whether ATG administration affects naïve and memory T cell differently is largely unknown. The context and purpose of the study In this study, we assessed how murine ATG therapy affected T cell subsets in NOD mice, based on their regulatory and naïve or memory phenotype, as well as its influence on antigen-specific immune responses. Results Peripheral blood CD4+ and CD8+ T cells post-ATG therapy declined to their lowest levels at day 3, while CD4+ T cells returned to normal levels more rapidly than CD8+ T cells. ATG therapy failed to eliminate antigen-primed T cells. CD4+ T cell responses post-ATG therapy skewed to T helper type 2 (Th2) and possibly IL-10-producing T regulatory type 1 (Tr1) cells. Intriguingly, Foxp3+ regulatory T cells (Tregs) were less sensitive to ATG depletion and remained at higher levels following in vivo recovery compared to controls. Of note, the frequency of Foxp3+ Tregs with memory T cell phenotype was significantly increased in ATG-treated animals. Conclusion ATG therapy may modulate antigen-specific immune responses through inducing memory-like regulatory T cells as well as other protective T cells such as Th2 and IL-10-producing Tr1 cells. PMID:23237483

  2. Using MHC Molecules to Define a Chlamydia T Cell Vaccine.

    PubMed

    Karunakaran, Karuna P; Yu, Hong; Foster, Leonard J; Brunham, Robert C

    2016-01-01

    Vaccines based on humoral immunity alone are unlikely to protect against infections caused by intracellular pathogens and today's most pressing infectious diseases of public health importance are caused by intracellular infections that include tuberculosis, malaria, HIV/AIDS, and others such as Chlamydia trachomatis. For these infections, vaccines that induce cellular immune responses are essential. Major impediments in developing such vaccines include difficulty in identifying relevant T cell antigens and delivering them in ways that elicit protective cellular immunity. Genomics and proteomics now provide tools to allow unbiased empirical identification of candidate T cell antigens. This approach represents an advance on bioinformatic searches for candidate T cell antigens. This chapter discusses an immunoproteomic approach we have used to identify Chlamydia T cell antigens. We further discuss how these T cell antigens can be developed into a human vaccine. PMID:27076145

  3. Increased Immune Response Variability during Simultaneous Viral Coinfection Leads to Unpredictability in CD8 T Cell Immunity and Pathogenesis

    PubMed Central

    Kenney, Laurie L.; Cornberg, Markus; Chen, Alex T.; Emonet, Sebastien; de la Torre, Juan Carlos

    2015-01-01

    ABSTRACT T cell memory is usually studied in the context of infection with a single pathogen in naive mice, but how memory develops during a coinfection with two pathogens, as frequently occurs in nature or after vaccination, is far less studied. Here, we questioned how the competition between immune responses to two viruses in the same naive host would influence the development of CD8 T cell memory and subsequent disease outcome upon challenge. Using two different models of coinfection, including the well-studied lymphocytic choriomeningitis (LCMV) and Pichinde (PICV) viruses, several differences were observed within the CD8 T cell responses to either virus. Compared to single-virus infection, coinfection resulted in substantial variation among mice in the size of epitope-specific T cell responses to each virus. Some mice had an overall reduced number of virus-specific cells to either one of the viruses, and other mice developed an immunodominant response to a normally subdominant, cross-reactive epitope (nucleoprotein residues 205 to 212, or NP205). These changes led to decreased protective immunity and enhanced pathology in some mice upon challenge with either of the original coinfecting viruses. In mice with PICV-dominant responses, during a high-dose challenge with LCMV clone 13, increased immunopathology was associated with a reduced number of LCMV-specific effector memory CD8 T cells. In mice with dominant cross-reactive memory responses, during challenge with PICV increased immunopathology was directly associated with these cross-reactive NP205-specific CD8 memory cells. In conclusion, the inherent competition between two simultaneous immune responses results in significant alterations in T cell immunity and subsequent disease outcome upon reexposure. IMPORTANCE Combination vaccines and simultaneous administration of vaccines are necessary to accommodate required immunizations and maintain vaccination rates. Antibody responses generally correlate with

  4. B and T cell screen

    MedlinePlus

    ... following, which might affect your T and B cell count: Chemotherapy HIV Radiation therapy Recent or current infection ... Abnormal T and B cell counts suggest a possible disease. Further ... to confirm a diagnosis. An increased T cell count may be due ...

  5. Regulation of the T cell response.

    PubMed

    Romagnani, S

    2006-11-01

    The T cell branch of the immune system can respond to a virtually infinite variety of exogenous antigens, thus including the possibility of self-antigen recognition and dangerous autoimmune reactions. Therefore, regulatory mechanisms operate both during ontogeny within the thymus and after birth in the periphery. The control of self-reactive T cells occurs through a process of negative selection that results in apoptosis of T cells showing high affinity for self-peptides expressed at the thymic level by means of promiscuous gene expression. Self-reactive T cells escaped to negative selection are controlled in the periphery by other regulatory mechanisms, the most important being natural Foxp3+ T regulatory (Treg) cells. Regulation is also required to control excessive effector T cell responses against exogenous antigens, when they become dangerous for the body. Three types of effector T cells have been recognized: T helper 1 (Th1) cells, which are protective against intracellular bacteria; Th2 cells, which play some role in the protection against nematodes, but are responsible for allergic reactions; Th17 cells, which are probably effective in the protection against extracellular bacteria, but also play a role in the amplification of autoimmune disorders. Abnormal or excessive Th effector responses are regulated by different mechanisms. Redirection or immune deviation of Th1- or Th2-dominated responses is provided by cytokines [interferon-gamma (IFN-gamma) vs. interleukin-4 (IL-4)] produced by the same cell types and by the CXCR3-binding chemokines CXCL4 and CXCL10. Moreover, both Th1 and Th2 responses can be suppressed by adaptive Treg cells through contact-dependent mechanisms and/or the production of IL-10 and transforming growth factor-beta (TGF-beta). Finally, TGF-beta1 can promote the development of both Th17 effector and adaptive Treg cells, while the contemporaneous production of IL-6 contributes to the development of Th17 cells, but inhibits Treg cells

  6. Human regulatory T cells control TCR signaling and susceptibility to suppression in CD4+ T cells.

    PubMed

    Chellappa, Stalin; Lieske, Nora V; Hagness, Morten; Line, Pål D; Taskén, Kjetil; Aandahl, Einar M

    2016-07-01

    Human CD4(+)CD25(hi)FOXP3(+) regulatory T cells maintain immunologic tolerance and prevent autoimmune and inflammatory immune responses. Regulatory T cells undergo a similar activation cycle as conventional CD4(+) T cells upon antigen stimulation. Here, we demonstrate that T cell receptors and costimulation are required to activate the regulatory T cell suppressive function. Regulatory T cells suppressed the T cell receptor signaling in effector T cells in a time-dependent manner that corresponded with inhibition of cytokine production and proliferation. Modulation of the activation level and thereby the suppressive capacity of regulatory T cells imposed distinct T cell receptor signaling signatures and hyporesponsiveness in suppressed and proliferating effector T cells and established a threshold for effector T cell proliferation. The immune suppression of effector T cells was completely reversible upon removal of regulatory T cells. However, the strength of prior immune suppression by regulatory T cells and corresponding T cell receptor signaling in effector T cells determined the susceptibility to suppression upon later reexposure to regulatory T cells. These findings demonstrate how the strength of the regulatory T cell suppressive function determines intracellular signaling, immune responsiveness, and the later susceptibility of effector T cells to immune suppression and contribute to unveiling the complex interactions between regulatory T cells and effector T cells. PMID:26715685

  7. An early defect in primary and secondary T cell responses in asymptomatic cats during acute feline immunodeficiency virus (FIV) infection.

    PubMed Central

    Bishop, S A; Williams, N A; Gruffydd-Jones, T J; Harbour, D A; Stokes, C R

    1992-01-01

    As in HIV infection of humans, cats infected with FIV are particularly susceptible to secondary infection by opportunistic pathogens, suggesting an impaired ability to elicit an effective immune response against foreign antigens. In order to investigate the development of immunity in FIV-infected cats, we have used an autologous culture system to directly measure priming of naive CD4+ T cells to soluble protein antigen, in vitro. Using this assay, we showed previously that cats infected with FIV for several months had significantly reduced primary proliferative responses. We have now examined cats before infection, and at varying times after infection with FIV, to determine how soon after infection this defect in T cell priming was evident, compared with other quantitative and qualitative measurements of lymphocyte function. Our results showed a progressive decline in immune function in asymptomatic cats during the acute stage of infection with FIV. Primary T cell responses were most sensitive and a significant reduction in proliferation of naive T cells to foreign antigen occurred 5 weeks after infection, despite normal blastogenesis to T cell mitogens and normal CD4+/CD8+ ratios at these times. Whilst lymphocyte proliferation to T cell mitogens was unaffected throughout, a significant reduction in proliferation to a B cell mitogen occurred from week 8 onwards. CD4+/CD8+ ratios fell significantly from week 13 onwards, and proliferation of the memory T cell population to a recall antigen was significantly impaired later, from week 19 onwards. The defect in the priming of naive T cells to foreign antigen early after infection may be important in determining susceptibility to secondary infections. PMID:1458687

  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. CD6 modulates thymocyte selection and peripheral T cell homeostasis.

    PubMed

    Orta-Mascaró, Marc; Consuegra-Fernández, Marta; Carreras, Esther; Roncagalli, Romain; Carreras-Sureda, Amado; Alvarez, Pilar; Girard, Laura; Simões, Inês; Martínez-Florensa, Mario; Aranda, Fernando; Merino, Ramón; Martínez, Vanesa-Gabriela; Vicente, Rubén; Merino, Jesús; Sarukhan, Adelaida; Malissen, Marie; Malissen, Bernard; Lozano, Francisco

    2016-07-25

    The CD6 glycoprotein is a lymphocyte surface receptor putatively involved in T cell development and activation. CD6 facilitates adhesion between T cells and antigen-presenting cells through its interaction with CD166/ALCAM (activated leukocyte cell adhesion molecule), and physically associates with the T cell receptor (TCR) at the center of the immunological synapse. However, its precise role during thymocyte development and peripheral T cell immune responses remains to be defined. Here, we analyze the in vivo consequences of CD6 deficiency. CD6(-/-) thymi showed a reduction in both CD4(+) and CD8(+) single-positive subsets, and double-positive thymocytes exhibited increased Ca(2+) mobilization to TCR cross-linking in vitro. Bone marrow chimera experiments revealed a T cell-autonomous selective disadvantage of CD6(-/-) T cells during development. The analysis of TCR-transgenic mice (OT-I and Marilyn) confirmed that abnormal T cell selection events occur in the absence of CD6. CD6(-/-) mice displayed increased frequencies of antigen-experienced peripheral T cells generated under certain levels of TCR signal strength or co-stimulation, such as effector/memory (CD4(+)TEM and CD8(+)TCM) and regulatory (T reg) T cells. The suppressive activity of CD6(-/-) T reg cells was diminished, and CD6(-/-) mice presented an exacerbated autoimmune response to collagen. Collectively, these data indicate that CD6 modulates the threshold for thymocyte selection and the generation and/or function of several peripheral T cell subpopulations, including T reg cells. PMID:27377588

  10. Human autoreactive T cells recognize CD1b and phospholipids

    PubMed Central

    Van Rhijn, Ildiko; van Berlo, Twan; Hilmenyuk, Tamara; Cheng, Tan-Yun; Wolf, Benjamin J.; Tatituri, Raju V. V.; Uldrich, Adam P.; Napolitani, Giorgio; Cerundolo, Vincenzo; Altman, John D.; Willemsen, Peter; Huang, Shouxiong; Rossjohn, Jamie; Besra, Gurdyal S.; Brenner, Michael B.; Godfrey, Dale I.; Moody, D. Branch

    2016-01-01

    In contrast with the common detection of T cells that recognize MHC, CD1a, CD1c, or CD1d proteins, CD1b autoreactive T cells have been difficult to isolate in humans. Here we report the development of polyvalent complexes of CD1b proteins and carbohydrate backbones (dextramers) and their use in identifying CD1b autoreactive T cells from human donors. Activation is mediated by αβ T-cell receptors (TCRs) binding to CD1b-phospholipid complexes, which is sufficient to activate autoreactive responses to CD1b-expressing cells. Using mass spectrometry and T-cell responses to scan through the major classes of phospholipids, we identified phosphatidylglycerol (PG) as the immunodominant lipid antigen. T cells did not discriminate the chemical differences that distinguish mammalian PG from bacterial PG. Whereas most models of T-cell recognition emphasize TCR discrimination of differing self and foreign structures, CD1b autoreactive T cells recognize lipids with dual self and foreign origin. PG is rare in the cellular membranes that carry CD1b proteins. However, bacteria and mitochondria are rich in PG, so these data point to a more general mechanism of immune detection of infection- or stress-associated lipids. PMID:26621732

  11. 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

  12. Comprehensive longitudinal analysis of hepatitis C virus (HCV)-specific T cell responses during acute HCV infection in the presence of existing HIV-1 infection.

    PubMed

    van den Berg, C H S B; Ruys, T A; Nanlohy, N M; Geerlings, S E; van der Meer, J T; Mulder, J-W; Lange, J A; van Baarle, D

    2009-04-01

    The aim of this study was to study the development of HCV-specific T cell immunity during acute HCV infection in the presence of an existing HIV-1 infection in four HIV-1 infected men having sex with men. A comprehensive analysis of HCV-specific T cell responses was performed at two time points during acute HCV infection using a T cell expansion assay with overlapping peptide pools spanning the entire HCV genome Three patients with (near) normal CD4+ T cell counts (range 400-970 x 10(6)/L) either resolved (n=1) or temporary suppressed HCV RNA. In contrast, one patient with low CD4+ T cell counts (330 x 10(6)/L), had sustained high HCV RNA levels. All four patients had low HCV-specific CD8+ T cell responses, and similar magnitudes of CD4+ T cell responses. Interestingly, individuals with resolved infection or temporary suppression of HCV-RNA had HCV-specific CD4+ T cell responses predominantly against nonstructural (NS) proteins. While the individual with high HCV RNA plasma concentrations had CD4+ T cell responses predominantly directed against Core. Our data show that an acute HCV infection in an HIV-1 infected person can be suppressed in the presence of HCV-specific CD4+ T cell response targeting non-structural proteins. However further research is needed in a larger group of patients to evaluate the role of HIV-1 on HCV-specific T cell responses in relation to outcome of acute HCV infection. PMID:19222746

  13. The regulatory role of interferon-γ producing gamma delta T cells via the suppression of T helper 17 cell activity in bleomycin-induced pulmonary fibrosis.

    PubMed

    Segawa, S; Goto, D; Iizuka, A; Kaneko, S; Yokosawa, M; Kondo, Y; Matsumoto, I; Sumida, T

    2016-09-01

    Interstitial pneumonia (IP) is a chronic progressive interstitial lung disease associated with poor prognosis and high mortality. However, the pathogenesis of IP remains to be elucidated. The aim of this study was to clarify the role of pulmonary γδT cells in IP. In wild-type (WT) mice exposed to bleomycin, pulmonary γδT cells were expanded and produced large amounts of interferon (IFN)-γ and interleukin (IL)-17A. Histological and biochemical analyses showed that bleomycin-induced IP was more severe in T cell receptor (TCR-δ-deficient (TCRδ(-/-) ) mice than WT mice. In TCRδ(-/-) mice, pulmonary IL-17A(+) CD4(+) Τ cells expanded at days 7 and 14 after bleomycin exposure. In TCRδ(-/-) mice infused with γδT cells from WT mice, the number of pulmonary IL-17A(+) CD4(+) T cells was lower than in TCRδ(-/-) mice. The examination of IL-17A(-/-) TCRδ(-/-) mice indicated that γδT cells suppressed pulmonary fibrosis through the suppression of IL-17A(+) CD4(+) T cells. The differentiation of T helper (Th)17 cells was determined in vitro, and CD4(+) cells isolated from TCRδ(-/-) mice showed normal differentiation of Th17 cells compared with WT mice. Th17 cell differentiation was suppressed in the presence of IFN-γ producing γδT cells in vitro. Pulmonary fibrosis was attenuated by IFN-γ-producing γδT cells through the suppression of pulmonary IL-17A(+) CD4(+) T cells. These results suggested that pulmonary γδT cells seem to play a regulatory role in the development of bleomycin-induced IP mouse model via the suppression of IL-17A production. PMID:27083148

  14. Genetic landscape of adult T-cell leukemia/lymphoma.

    PubMed

    Kataoka, Keisuke; Ogawa, Seishi

    2016-04-01

    Adult T-cell leukemia/lymphoma (ATL) is a peripheral T-cell malignancy associated with HTLV-1 infection. To decipher the genetic landscape of ATL, we performed an integrated molecular analysis, which included whole-genome, whole-exome, transcriptome and targeted sequencing, as well as array-based copy number and methylation analyses. The somatic alterations are highly enriched for T-cell receptor/NF-κB signaling, the G-protein coupled receptor associated with T-cell migration, and other T-cell-related pathways as well as immune surveillance related genes. Among these, PLCG1, PRKCB, CARD11, VAV1, IRF4, CCR4, and CCR7 activating mutations and CTLA4-CD28 and ICOS-CD28 fusion genes have been identified. In addition, these genes significantly overlap with HTLV-1 Tax interactome. These results provide an important basis for the development of new ATL diagnostics and therapeuticsregimens. PMID:27169444

  15. Strategies to genetically engineer T cells for cancer immunotherapy.

    PubMed

    Spear, Timothy T; Nagato, Kaoru; Nishimura, Michael I

    2016-06-01

    Immunotherapy is one of the most promising and innovative approaches to treat cancer, viral infections, and other immune-modulated diseases. Adoptive immunotherapy using gene-modified T cells is an exciting and rapidly evolving field. Exploiting knowledge of basic T cell biology and immune cell receptor function has fostered innovative approaches to modify immune cell function. Highly translatable clinical technologies have been developed to redirect T cell specificity by introducing designed receptors. The ability to engineer T cells to manifest desired phenotypes and functions is now a thrilling reality. In this review, we focus on outlining different varieties of genetically engineered T cells, their respective advantages and disadvantages as tools for immunotherapy, and their promise and drawbacks in the clinic. PMID:27138532

  16. How Chimeric Antigen Receptor Design Affects Adoptive T Cell Therapy.

    PubMed

    Gacerez, Albert T; Arellano, Benjamine; Sentman, Charles L

    2016-12-01

    Chimeric antigen receptor (CAR) T cells have been developed to treat tumors and have shown great success against B cell malignancies. Exploiting modular designs and swappable domains, CARs can target an array of cell surface antigens and, upon receptor-ligand interactions, direct signaling cascades, thereby driving T cell effector functions. CARs have been designed using receptors, ligands, or scFv binding domains. Different regions of a CAR have each been