DOCSLIB.ORG

Function Foxp3 and Its Effect on Regulatory T Cell Regulation Of

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Function Foxp3 and Its Effect on Regulatory T Cell Regulation Of Regulation of MHC Class I Expression by Foxp3 and Its Effect on Regulatory T Cell Function This information is current as Jie Mu, Xuguang Tai, Shankar S. Iyer, Jocelyn D. of September 25, 2021. Weissman, Alfred Singer and Dinah S. Singer J Immunol 2014; 192:2892-2903; Prepublished online 12 February 2014; doi: 10.4049/jimmunol.1302847 http://www.jimmunol.org/content/192/6/2892 Downloaded from Supplementary http://www.jimmunol.org/content/suppl/2014/02/12/jimmunol.130284 Material 7.DCSupplemental http://www.jimmunol.org/ References This article cites 38 articles, 11 of which you can access for free at: http://www.jimmunol.org/content/192/6/2892.full#ref-list-1 Why The JI? Submit online. • Rapid Reviews! 30 days* from submission to initial decision by guest on September 25, 2021 • No Triage! Every submission reviewed by practicing scientists • Fast Publication! 4 weeks from acceptance to publication *average Subscription Information about subscribing to The Journal of Immunology is online at: http://jimmunol.org/subscription Permissions Submit copyright permission requests at: http://www.aai.org/About/Publications/JI/copyright.html Email Alerts Receive free email-alerts when new articles cite this article. Sign up at: http://jimmunol.org/alerts The Journal of Immunology is published twice each month by The American Association of Immunologists, Inc., 1451 Rockville Pike, Suite 650, Rockville, MD 20852 All rights reserved. Print ISSN: 0022-1767 Online ISSN: 1550-6606. The Journal of Immunology Regulation of MHC Class I Expression by Foxp3 and Its Effect on Regulatory T Cell Function Jie Mu,1 Xuguang Tai,1 Shankar S. Iyer,2 Jocelyn D. Weissman, Alfred Singer, and Dinah S. Singer Expression of MHC class I molecules, which provide immune surveillance against intracellular pathogens, is higher on lymphoid cells than on any other cell types. In T cells, this is a result of activation of class I transcription by the T cell enhanceosome consisting of Runx1, CBFb, and LEF1. We now report that MHC class I transcription in T cells also is enhanced by Foxp3, resulting in higher levels of class I in CD4+CD25+ T regulatory cells than in conventional CD4+CD252 T cells. Interestingly, the effect of Foxp3 regulation of MHC class I transcription is cell type specific: Foxp3 increases MHC class I expression in T cells but represses it in epithelial tumor cells. In both cell types, Foxp3 targets the upstream IFN response element and downstream core promoter of the class I gene. Importantly, expression of MHC class I contributes to the function of CD4+CD25+ T regulatory cells by enhancing Downloaded from immune suppression, both in in vitro and in vivo. These findings identify MHC class I genes as direct targets of Foxp3 whose expression augments regulatory T cell function. The Journal of Immunology, 2014, 192: 2892–2903. ajor histocompatibility class I molecules function to which integrates upstream signals targeting distinct transcription provide immune surveillance against intracellular patho- starts in response to tissue-specific or dynamic signals (5, 6). M gens. In the mature immune system, presentation offoreign A variety of DNA-binding transcription factors have been http://www.jimmunol.org/ peptides by class I molecules regulates both innate and adaptive identified that interact either directly or indirectly with tissue- immunity by inhibiting nonspecific NK responses and triggering specific and hormone-specific regulatory elements. For example, specific CTL responses, respectively. During development, MHCclass a B lymphocyte–specific enhanceosome consisting of the coac- I expression on nonhematopoietic thymic epithelial cells is essential tivator CIITA and DNA-bound transcription factors RFX, CREB/ for the maturation and survival of CD8+ T cells. Although originally ATF, and NF-Y leads to high cell surface class I and II expression thought to be passive receptors of intracellularly derived peptides, in B cells (8–11). In T cells, the constitutive high level expression emerging evidence reveals that maintenance of homeostatic levels of class I is not due to CIITA but is established by a T cell en- of MHC class I is critical for a functional immune response (1–4). hanceosome consisting of RUNX1, CBFb, and LEF1 (12). Whether MHC class I molecules are ubiquitously expressed in somatic additional factors in the different T cell subsets superimpose on by guest on September 25, 2021 cells, although at different levels in different cell types, and their the T cell enhanceosome to differentially regulate MHC class I expression is dynamically regulated by hormones and cytokines. expression has not been examined previously. Lymphoid cells express the highest levels of class I, whereas In the present study, we have examined the regulation of MHC neurons express two orders of magnitude less. MHC class I ex- class I expression in T cell subsets. We report that class I levels in pression is controlled transcriptionally by the interaction of tissue- CD4+CD25+ T regulatory cells are consistently higher than in specific transcription factors with cognate DNA sequence elements either conventional CD4+ T effector cells or CD8+ T cells as a result on the extended class I promoter. The DNA sequence elements that of Foxp3-mediated transcriptional activation. Importantly, these mediate class I regulation have been mapped to distinct domains elevated levels of class I contribute to efficient regulatory T cell that mediate tissue-specific and hormone-specific signals (3, 5–7). (Treg) suppressive function. Surprisingly, Foxp3 affects MHC Transcription initiates at multiple sites within the core promoter, class I transcription differently in different cell types as it represses class I transcription in epithelial tumor cells. Thus, these studies show that Foxp3 is an active, context-dependent regulator of MHC Experimental Immunology Branch, Center for Cancer Research, National Cancer class I expression and function. Institute, National Institutes of Health, Bethesda, MD 20892 1J.M. and X.T. contributed equally to this work. Materials and Methods 2Current address: Molecular Biology Institute, University of California, Los Angeles, Animals Los Angeles, CA. 2/2 2/2 2/2 b2-microglobulin (b2m) and b2m RAG2 mice were bred in the Received for publication October 22, 2013. Accepted for publication January 16, National Cancer Institute Center for Cancer Research animal colony. PD1 2014. transgenic mice and Foxp3 transgenic mice (A10 and T3) have been de- This work was supported by the Intramural Research Program of the National In- scribed previously (13, 14). The PD1 dropout transgenic mouse was gen- stitutes of Health, National Cancer Institute, Center for Cancer Research. erated in the National Cancer Institute core facility by microinjection of 2 Address correspondence and reprint requests to Dr. Dinah S. Singer, Experimental a genomic clone of PD1 from which 50 to +3 bp of promoter sequences Immunology Branch, National Cancer Institute, National Institutes of Health, Build- were deleted. B6 (CD45.2) mice were purchased from The Jackson Labo- ing 10, Room 4B-36, Bethesda, MD 20892. E-mail address: [email protected] ratory (Bar Harbor, ME), and B6 (CD45.1) mice were obtained from the The online version of this article contains supplemental material. Frederick Cancer Research Center (Frederick, MD). All mice were cared for in accordance with National Institutes of Health guidelines. Abbreviations used in this article: DP, double-positive; FKH, forkhead; IBD, inflam- matory bowel disease; IRE, IFN response element; LN, lymph node; LNT, lymph Reagents for flow cytometry and protein immunoblotting node T; b2m, b2-microglobulin; MFI, mean fluorescence intensity; SP, single-posi- tive; TCE, T cell enhanceosome; Tconv, conventional T cell; Treg, regulatory T cell; mAbs with the following specificities were used in this study: CD4 (RM4.5 WT, wild-type. and GK1.5), CD25 (PC61 and 7D4), H-2Kb (AF6-88.5), H-2Db (28-14-8), www.jimmunol.org/cgi/doi/10.4049/jimmunol.1302847 The Journal of Immunology 2893 H-2Kd (SF1-1.1), H-2Dd (34-2-12), CD45.1 (A20), CD45.2 (104), CD45RB irradiated T cell–depleted B6 spleen cells (2000R) as accessory cells (16A), and CD152 (CTLA-4; UC10-4F10-11) were obtained from BD (APCs) and stimulated with anti-CD3 mAb (1 mg/ml) and/or rIL-2 (200 Biosciences (San Diego, CA); PD1 and HLA class I (PT85A with specificity U/ml) for 72 h. For in vitro suppression assays, CD4+CD252 responder for both porcine and human MHC class I, but not mouse MHC class I) T cells (3–5 3 104/well) were cultured with an equal number of CD4+ were obtained from VMRD (Pullman, WA); and Foxp3 (FJK-16s) was CD25+ T cells, APCs, and anti-CD3 mAb (1 mg/ml) for 72 h. Where in- obtained from eBioscience (San Diego, CA). Stained cells were analyzed dicated, cultures were pulsed with [3H]thymidine 8 h prior to harvest. on a BD LSR flow cytometer (Becton Dickinson). Where indicated, fluo- Alternatively, CFSE-labeled CD4+CD252 responder T cells were cocul- rescence was quantified and expressed as mean fluorescence intensity (MFI). turedwithCD4+CD25+ and APCs (which expressed a different CD45 Abs with the following specificities were used for protein immuno- allele from the Tconvs) and stimulated with anti-CD3 (1 mg/ml) for 72 h. blotting: FLAG from Sigma-Aldrich (St. Louis, MO), and heat shock At the end of culture, CFSE fluorescence of the responder T cells was protein 60 from Santa Cruz Biotechnology (Santa Cruz, CA). Total cell determined. lysates from transfected HeLa or Jurkat cells were resolved by SDS-PAGE followed by blotting. T cell reconstitution and in vivo induction of inflammatory bowl disease Cells lines and cultivation b2m2/2RAG22/2 mice were injected i.v. with 4 3 105 purified CD4+ HeLa epithelial cells were grown in DMEM supplemented with 10% FBS, CD45RBhi T cells either alone or in combination with 4 3 105 CD4+ 2mML-glutamine, 20 mM HEPES (pH 7.2), and gentamicin sulfate (10 ng/ CD25+ T cells from the indicated sources.
Load more

Recommended publications
  • Major Histocompatibility Complex-Restricted
    MAJOR HISTOCOMPATIBILITY COMPLEX-RESTRICTED SELF-RECOGNITION IN RESPONSES TO TRINITROPHENYL-FICOLL A Novel Cell Interaction Pathway Requiring Self-Recognition of Accessory Cell H-2 Determinants by Both T Cells and B Cells By RICHARD J. HODES, KAREN S. HATHCOCK, AND ALFRED SINGER From the Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20205 Most thymus-dependent (T) lymphocyte populations are restricted in their function by a requirement for recognition of"self" major histocompatibility complex (MHC) 1 gene products. Thus, T cells that mediate help (Tn) (1-5), antigen-specific prolifera- tion (6, 7), cell-mediated lympholysis (8, 9), delayed-type hypersensitivity (10), and immune suppression (11) require recognition of MHC products expressed by the cells with which they interact. In addition to MHC restriction of T cell recognition, the possibility that B cells as well as T cells may be capable of MHC-restricted self- recognition has recently been evaluated (12-15). In a recent report (15), the possibility that trinitrophenyl (TNP)-Ficoll-responsive B cells are MHC restricted in their interaction with accessory cells was assessed under T-independent (TI) response conditions. In the absence of any detectable requirement for T cells, it was demon- strated that TNP-Ficoll-responsive B cells, as a consequence of their development in a fully MHC-allogeneic chimeric host environment, were unable to cooperate with accessory cells expressing syngeneic donor-type MHC determinants but could coop- erate with accessory cells expressing allogeneic host-type MHC products. These findings raised a number of other questions. Although they demonstrated that B cells could express MHC-restricted self-recognition in the absence of T cells, these studies did not determine the effects that T cells or their soluble products could exert on this B cell function.
    [Show full text]
  • The Basis of T Cell Development and Lineage Choice in the Thymus
    Chiba Medical J. 94E：19－23， 2018 doi:10.20776/S03035476-94E-3-P19 〔 Chiba Medical Society Award Review 〕 The basis of T cell development and lineage choice in the thymus Motoko Y. Kimura Department of Medical Immunology and Department of Immunology Graduate School of Medicine, Chiba University, Chiba 260-8670. （Accepted March 22, 2018） Abstract The thymus is the only organ that produces T cells where immature thymocytes are properly educated and make the correct decision to become appropriate lineage T cells such as CD4+ or CD8+ T cells. This process is referred to as‘ lineage choice’. Failure in T cell development and/or lineage choice is a direct cause of severe immunodeficiency and/or severe autoimmune disorders. Thus, it is extremely important to understand the molecular mechanisms of thymocyte development and lineage choice and many immunologists have studied this issue intensively. A diverse TCR repertoire（ nearly 1018） is generated by TCR gene rearrangement in immature thymocytes. It contains autoreactive T cells as well as useless T cells that cannot recognize self- MHC molecules. These useless T cells are negatively selected（ i.e. clonal deletion）, and only cells that moderately recognize self-MHC molecules are positively selected. These processes are termed negative and positive selection. Positively selected cells further differentiate into either CD4T cells or CD8T cells, depending on their specificity to MHC-II or MHC-I respectively. How can the lineage choice of T cells, which have a huge TCR repertoire, be properly determined during their development? In this review, I will update the recent understanding of the molecular mechanisms underlying the CD4/CD8 lineage choices in the thymus and explain the mechanisms of error-free MHC-I-dependent CD8 T cell development.
    [Show full text]
  • EARLY DEVELOPMENT of the T CELL REPERTOIRE in Vivo
    EARLY DEVELOPMENT OF THE T CELL REPERTOIRE In Vivo Treatment of Neonatal Mice with Anti-Ia Antibodies Interferes with Differentiation of I-restricted T Cells But Not K/D-restricted T Ceils By ADAM. KRUISBEEK,* MARION J. FULTZ, SUSAN O. SHARROW, ALFRED SINGER, AND JAMES J. MOND Downloaded from http://rupress.org/jem/article-pdf/157/6/1932/1394059/1932.pdf by guest on 29 September 2021 From the Immunology Branch, National Cancer Institute, National Institutes of Health, and the Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20205 A large number of studies have indicated that the activation of T helper cells for both antibody (1-6) and cytolytic T lymphocyte (CTL) 1 (7-11) 2 responses is restricted by products of the I region of the major histocompatibility complex (MHC), while the activation of CTL themselves is restricted by products of the K/D regions of the MHC (12-14). However, it is less clear how and when during their developmental pathway T ceils acquire their MHC-restricted self-recognition specificity. Studies with chimeras (12, 15, 16) and thymus-grafted nude mice (17, 18) have indicated that the MHC phenotype of the thymus dictates the particular MHC determinants that T cells recognize as self-recognition elements. In addition, the MHC phenotype of the extra-thymic environment has been implicated in the process that determines the restriction specificities of T cells (11, 14, 17, 19, 20). In vivo manipulation of the expression of MHC products may yield a better understanding of how the host environment (thymic or extra-thymic) determines restriction specificities of T ceils.
    [Show full text]
  • Function Foxp3 and Its Effect on Regulatory T Cell Regulation Of
    Regulation of MHC Class I Expression by Foxp3 and Its Effect on Regulatory T Cell Function This information is current as Jie Mu, Xuguang Tai, Shankar S. Iyer, Jocelyn D. of September 26, 2021. Weissman, Alfred Singer and Dinah S. Singer J Immunol 2014; 192:2892-2903; Prepublished online 12 February 2014; doi: 10.4049/jimmunol.1302847 http://www.jimmunol.org/content/192/6/2892 Downloaded from Supplementary http://www.jimmunol.org/content/suppl/2014/02/12/jimmunol.130284 Material 7.DCSupplemental http://www.jimmunol.org/ References This article cites 38 articles, 11 of which you can access for free at: http://www.jimmunol.org/content/192/6/2892.full#ref-list-1 Why The JI? Submit online. • Rapid Reviews! 30 days* from submission to initial decision by guest on September 26, 2021 • No Triage! Every submission reviewed by practicing scientists • Fast Publication! 4 weeks from acceptance to publication *average Subscription Information about subscribing to The Journal of Immunology is online at: http://jimmunol.org/subscription Permissions Submit copyright permission requests at: http://www.aai.org/About/Publications/JI/copyright.html Email Alerts Receive free email-alerts when new articles cite this article. Sign up at: http://jimmunol.org/alerts The Journal of Immunology is published twice each month by The American Association of Immunologists, Inc., 1451 Rockville Pike, Suite 650, Rockville, MD 20852 All rights reserved. Print ISSN: 0022-1767 Online ISSN: 1550-6606. The Journal of Immunology Regulation of MHC Class I Expression by Foxp3 and Its Effect on Regulatory T Cell Function Jie Mu,1 Xuguang Tai,1 Shankar S.
    [Show full text]
  • Coreceptor Reversal in the Thymus: Signaled CD4 8 Thymocytes
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Immunity, Vol. 13, 59±71, July, 2000, Copyright 2000 by Cell Press Coreceptor Reversal in the Thymus: Signaled CD4؉8؉ Thymocytes Initially Terminate CD8 Transcription Even When Differentiating into CD8؉ T Cells Enrico Brugnera,*§ Avinash Bhandoola,* thymocytes into mature SP T cells is referred to as ªposi- Ricardo Cibotti,*k Qing Yu,* tive selectionº and requires termination of one or the Terry I. Guinter,* Yoshio Yamashita,²# other coreceptor molecule. The choice of which core- Susan O. Sharrow,* and Alfred Singer*³ ceptor molecule to extinguish is referred to as ªlineage *Experimental Immunology Branch commitmentº (Janeway, 1988) and is a critical one for National Cancer Institute signaled DP thymocytes, as a functionally competent Bethesda, Maryland 20892 immune system requires each T cell to express TCR ² Immunobiology Program and coreceptor molecules with concordant MHC speci- Oklahoma Medical Research Foundation ficities (Ellmeier et al., 1999). That is, immunocompe- Oklahama City, Oklahoma 73104 tence requires that TCR with specificity for MHC class II (MHC II) antigenic complexes be expressed on CD4SP T cells, while TCR with specificity for MHC class I (MHC I) antigenic complexes be expressed on CD8SP T cells. Summary Different mechanisms have been proposed to explain how DP thymocytes can differentiate into SP T cells A central paradigm of T cell development is that expressing TCR and coreceptor molecules with match- CD4؉8؉ (DP) thymocytes differentiate into CD4؉ or ing MHC specificities (Janeway, 1988; Davis et al., 1993; CD8؉ T cells in response to intrathymic signals that von Boehmer, 1996; Basson et al., 1998; Chan et al., extinguish transcription of the inappropriate corecep- 1998; Hedrick and Sharp, 1998; Singer et al., 1999).
    [Show full text]
  • Tcrhibcl-2Hi) Subset of CD4+CD8+ Thymocytes Has Selectively Terminated CD4 Or CD8 Synthesis
    Haverford College Haverford Scholarship Faculty Publications Biology 1996 Lineage commitment in the thymus: only the most differentiated (TCRhibcl-2hi) subset of CD4+CD8+ thymocytes has selectively terminated CD4 or CD8 synthesis Jennifer Punt Haverford College Harumi Suzuki Larry C. Granger Susan O. Sharrow Follow this and additional works at: https://scholarship.haverford.edu/biology_facpubs Repository Citation Punt, J. A ., H. Suzuki, L. C. Granger, S.O. Sharrow, and A. Singer. (1996). Lineage commitment in the thymus: Only the most differentiated (TCR hi bcl - 2 hi ) subset of CD4 + CD8 + thymocytes has selectively terminated CD4 or CD8 synthesis. J.Exp. Med . , 184: 2091 - 2099. This Journal Article is brought to you for free and open access by the Biology at Haverford Scholarship. It has been accepted for inclusion in Faculty Publications by an authorized administrator of Haverford Scholarship. For more information, please contact [email protected]. Published December 1, 1996 Lineage Commitment in the Thymus: Only the Most Differentiated (TCRhibcl-2hi) Subset of CD41CD81 Thymocytes Has Selectively Terminated CD4 or CD8 Synthesis By Jennifer A. Punt, Harumi Suzuki, Larry G. Granger, Susan O. Sharrow, and Alfred Singer From the Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland Summary Lineage commitment is a developmental process by which individual CD41CD81 (double Downloaded from positive, DP) thymocytes make a decision to differentiate into either CD41 or CD81 T cells. However, the molecular event(s) that defines lineage commitment is controversial. We have previously proposed that lineage commitment in DP thymocytes can be molecularly defined as the selective termination of CD4 or CD8 coreceptor synthesis.
    [Show full text]
  • How Thymocytes Achieve Their Fate Dan R
    How Thymocytes Achieve Their Fate Dan R. Littman J Immunol 2016; 196:1983-1984; ; This information is current as doi: 10.4049/jimmunol.1600032 of September 29, 2021. http://www.jimmunol.org/content/196/5/1983 Downloaded from Supplementary http://www.jimmunol.org/content/suppl/2016/02/18/196.5.1983.DC1 Material References This article cites 18 articles, 4 of which you can access for free at: http://www.jimmunol.org/content/196/5/1983.full#ref-list-1 http://www.jimmunol.org/ Why The JI? Submit online. • Rapid Reviews! 30 days* from submission to initial decision • No Triage! Every submission reviewed by practicing scientists • Fast Publication! 4 weeks from acceptance to publication by guest on September 29, 2021 *average Subscription Information about subscribing to The Journal of Immunology is online at: http://jimmunol.org/subscription Permissions Submit copyright permission requests at: http://www.aai.org/About/Publications/JI/copyright.html Email Alerts Receive free email-alerts when new articles cite this article. Sign up at: http://jimmunol.org/alerts The Journal of Immunology is published twice each month by The American Association of Immunologists, Inc., 1451 Rockville Pike, Suite 650, Rockville, MD 20852 Copyright © 2016 by The American Association of Immunologists, Inc. All rights reserved. Print ISSN: 0022-1767 Online ISSN: 1550-6606. Th eJournal of Pillars of Immunology Immunology How Thymocytes Achieve Their Fate Dan R. Littman ne of the central principles of adaptive immunity is worthy of further investigation, motivating the experiments the subdivision of T lymphocytes into functionally described in the Pillars of Immunology article by Alfred Singer O distinct subsets.
    [Show full text]
  • Assessing T Cell Intrinsic and Extrinsic IL-15 Expression with Il15 Gene Reporter Mice
    Immune Netw. 2018 Feb;18(1):e13 https://doi.org/10.4110/in.2018.18.e13 pISSN 1598-2629·eISSN 2092-6685 Review Article Out-sourcing for Trans-presentation: Assessing T Cell Intrinsic and Extrinsic IL-15 Expression with Il15 Gene Reporter Mice Joo-Young Park, Davinna L. Ligons, Jung-Hyun Park* Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA Received: Oct 29, 2017 ABSTRACT Revised: Feb 13, 2018 Accepted: Feb 13, 2018 IL-15 is a cytokine of the common γ-chain family that is critical for natural killer (NK), *Correspondence to invariant natural killer T (iNKT), and CD8 memory T cell development and homeostasis. The Jung-Hyun Park role of IL-15 in regulating effector T cell subsets, however, remains incompletely understood. Experimental Immunology Branch, National IL-15 is mostly expressed by stromal cells, myeloid cells, and dendritic cells (DCs). Whether Cancer Institute, NIH Building 10, Room 5B17, T cells themselves can express IL-15, and if so, whether such T cell-derived IL-15 could play 10 Center Drive, Bethesda, MD 20892, USA. an autocrine role in T cells are interesting questions that were previously addressed but E-mail: [email protected] answered with mixed results. Recently, three independent studies described the generation Copyright © 2018. The Korean Association of of IL-15 reporter mice which facilitated the identification of IL-15-producing cells and helped Immunologists to clarify the role of IL-15 both in vitro and in vivo. Here, we review the findings of these studies This is an Open Access article distributed and place them in context of recent reports that examined T cell-intrinsic IL-15 expression under the terms of the Creative Commons Attribution Non-Commercial License (https:// during CD4 effector T cell differentiation.
    [Show full text]
  • CHARACTERIZATION of ANTIGEN-SPECIFIC, Ia-RESTRICTED, L3T4 + CYTOLYTIC T LYMPHOCYTES and ASSESSMENT of THYMIC INFLUENCE on THEIR SELF SPECIFICITY
    CHARACTERIZATION OF ANTIGEN-SPECIFIC, Ia-RESTRICTED, L3T4 + CYTOLYTIC T LYMPHOCYTES AND ASSESSMENT OF THYMIC INFLUENCE ON THEIR SELF SPECIFICITY BY HANA GOLDING, TERRY I. MUNITZ, AND ALFRED SINGER From the Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20205 The specificity of many T cells for self major histocompatibility complex (MHC)~-encoded determinants is influenced by the MHC phenotype of the thymus in which their precursors had differentiated (1, 2). However, the intra- thymic events that influence the developing T cell repertoire are poorly under- stood. To enhance our understanding of these events it is necessary to know if the thymus influences the self specificity of all T cells equally, or primarily influences the self specificity of certain subsets of T cells. Previous studies examining the self specificity of individual T cell subpopulations noted that, in both radiation bone marrow chimeras and thymic chimeras, the self specificity of class II-restricted T helper (Th) cells was profoundly skewed toward the haplotype of the chimeric thymus (3-5), whereas the self specificity of class I- restricted cytolytic T lymphocyte precursors (pCTL) did not appear to be significantly skewed toward the thymic haplotype (6-8). This dichotomy was not due to differences in the antigen responses used to assess the self specificities of these two T cell subpopulations, since the dichotomy was subsequently observed between antihapten Th cells and antihapten pCTL present in a single-response system to hapten-modified self (9, 10). Thus, these results indicated that, in the chimera model of T cell differentiation, not all T cell subpopulations were equally influenced by the MHC phenotype of the chimeric thymus.
    [Show full text]
  • Crosstalk in the Mouse Thymus Willem Van Ewijk, Elisabeth W
    viewpoint Crosstalk in the mouse thymus Willem van Ewijk, Elisabeth W. Shores and Alfred Singer The development of mature T cells within the thymus is dependent upon intact cortical and medullary microenviromnents. In turn, tbymic microen- viromnents themseh,es are dependent on lymphoid cells to maintain their integrity Here, Willem van Ewijk and colleagues discuss experiments tbat have establisbed the pbenomenon of 'crosstalk' witbin the mouse thymus and suggest a mecbanism whereby lymphoid and stromal cells influence each otber in a consecutive manner during T-cell development. Prothymocytes, upon entering the thymus, communicate During migration, thymocytes acquire receptors for with a varieD" of nonlymphoid {stromal) cell types during growth factors, begin expression of adhesion molecules their development ~-~. The sequential interaction of and co-receptors, such as CD4 and CD8, and finally thvmocvtes with bone-marrow-derived macrophages, develop a T-cell receptor (TCR)/CD3 complex at the cortical epithelial cells and interdigitating reticulum cells cell surface~. Most importa,tly, the T-cell repertoire is (dendritic cells) leads to the proliferation, maturation shaped during differentiation, such that T cells with and selection of the developing T cells. The sequence high affinity for self major histocompatibili.~' complex of these lympho--stromal interactions reflects an intra- (MHC) molecules, or self peptides presented by these thvmic migration route, where prothymocytes travel molecules, are clonally eliminated 6. By contrast, T cells from the cortico--medullary junction through the thymic with affinity for foreign peptides presented by self parenchyma towards the outer (subcapsular) cortex. MHC molecules are positively selected 7,s. From there, differentiating thvmocytes move down the cortex to enter the thymic medulla as mature T cells.
    [Show full text]
  • Molecular Constraints on CDR3 for Thymic Selection of MHC-Restricted Tcrs from a Random Pre-Selection Repertoire
    ARTICLE https://doi.org/10.1038/s41467-019-08906-7 OPEN Molecular constraints on CDR3 for thymic selection of MHC-restricted TCRs from a random pre-selection repertoire Jinghua Lu1, François Van Laethem2, Abhisek Bhattacharya2, Marco Craveiro 2, Ingrid Saba2, Jonathan Chu1, Nicholas C. Love2, Anastasia Tikhonova2, Sergei Radaev1, Xiaoping Sun3, Annette Ko3, Tomer Arnon4,5, Eric Shifrut4, Nir Friedman 4, Nan-Ping Weng3, Alfred Singer2 & Peter D. Sun1 1234567890():,; The αβ T cell receptor (TCR) repertoire on mature T cells is selected in the thymus, but the basis for thymic selection of MHC-restricted TCRs from a randomly generated pre-selection repertoire is not known. Here we perform comparative repertoire sequence analyses of pre- selection and post-selection TCR from multiple MHC-sufficient and MHC-deficient mouse strains, and find that MHC-restricted and MHC-independent TCRs are primarily dis- tinguished by features in their non-germline CDR3 regions, with many pre-selection CDR3 sequences not compatible with MHC-binding. Thymic selection of MHC-independent TCR is largely unconstrained, but the selection of MHC-specific TCR is restricted by both CDR3 length and specific amino acid usage. MHC-restriction disfavors TCR with CDR3 longer than 13 amino acids, limits positively charged and hydrophobic amino acids in CDR3β, and clonally deletes TCRs with cysteines in their CDR3 peptide-binding regions. Together, these MHC-imposed structural constraints form the basis to shape VDJ recombination sequences into MHC-restricted repertoires. 1 Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, MD 20852, USA. 2 Experimental Immunology Branch, National Cancer Institute, Bethesda, MD 20892, USA.
    [Show full text]
  • Regulation of T Cell Receptor Expression in Imrnature CD4+CD8
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by PubMed Central Regulation of T Cell Receptor Expression in Imrnature CD4+CD8 + Thymocytes by p56 k-k Tyrosine Kinase: Basis for Differential Signaling by CD4 and CD8 in Immature Thymocytes Expressing Both Coreceptor Molecules By David L. Wiest,* Lydia Yuan,g Jane Jefferson,~ Patricia Benveniste,* Maria Tsokos,~ Richard D. Klausner,$ Laurie H. Glimcher,II Lawrence E. Samelson,S and Alfred Singer* From the "Experimental Immunology Branch, National Cancer Institute, *Laboratory of Pathology, National Cancer Institute, $Cell Biology and Metabolism Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethescla, Maryland 20892; and the IIDepartment of Cancer Biology and Medicine, Harvard School of Public Health, Boston, Massachusetts 02115 Summary Signals transduced through the T cell antigen receptor (TCR) are modulated by the src family tyrosine kinase p56 kk (lck), which associates in mature T cells with the coreceptor molecules CD4 and CD8. Here we describe a novel function oflck in immature CD4+CD8 + thymocytes, that of regulating TCR expression. Activation of lck in immature CD4 +CD8 + thymocytes by intrathymic engagement of CD4 maintains low TCR expression by causing most TCR components to be retained and degraded within the endoplasmic reticulum. Importantly, activation of lck in immature CD4 § CD8 § thymocytes results from engagement of surface CD4 molecules, but not surface CD8 molecules, despite the nearly fourfold greater surface expression of CD8 than CD4. The competence of CD4 to activate Ick in CD4 +CD8 § thymocytes relates to the fact that a relatively large fraction of surface CD4 molecules (25-50%) are associated with intracellular lck molecules, whereas only 2% of surface CD8 molecules are associated with lck.
    [Show full text]