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Harrer DC, Eder M, Barden M, Pan H, Herr W, Abken H. Ectopic PU.1 Expression Provides Chimeric Antigen Receptor (CAR) T Cells with Innate Cell Capacities Including IFN-β Release. Cancers (Basel) 2024; 16:2737. [PMID: 39123467 PMCID: PMC11311516 DOI: 10.3390/cancers16152737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2024] [Revised: 07/25/2024] [Accepted: 07/29/2024] [Indexed: 08/12/2024] Open
Abstract
Chimeric antigen receptor (CAR) T cell therapy has achieved extraordinary success in eliminating B cell malignancies; however, so far, it has shown limited efficacy in the treatment of solid tumors, which is thought to be due to insufficient CAR T cell activation. We hypothesized that the transcription factor PU.1, a master regulator of innate cell functionality, may augment pro-inflammatory CAR T cell activation. T cells were engineered with a CEA-specific CAR together with the constitutive expression of PU.1. CAR-redirected T cell activation was recorded for canonical functionality in vitro under conditions of prolonged repetitive antigen exposure. Ectopic PU.1 expression in CAR T cells upregulated the costimulatory receptors CD40, CD80, CD86, and CD70, which, unexpectedly, did not augment effector functions but hampered the upregulation of 4-1BB, decreased IL-2 production, reduced CAR T cell proliferation, and impaired their cytotoxic capacities. Under "stress" conditions of repetitive engagement of cognate tumor cells, CAR T cells with ectopic PU.1 showed reduced persistence, and finally failed to control the growth of cancer cells. Mechanistically, PU.1 caused CAR T cells to secrete IFN-β, a cytokine known to promote CAR T cell attrition and apoptosis. Collectively, PU.1 can polarize the functional capacities of CAR T cells towards innate cells.
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Affiliation(s)
- Dennis Christoph Harrer
- Department of Hematology and Internal Oncology, University Hospital Regensburg, 93053 Regensburg, Germany;
- Leibniz Institute for Immunotherapy, Division of Genetic Immunotherapy, University Regensburg, 93053 Regensburg, Germany; (M.E.); (M.B.); (H.P.); (H.A.)
| | - Matthias Eder
- Leibniz Institute for Immunotherapy, Division of Genetic Immunotherapy, University Regensburg, 93053 Regensburg, Germany; (M.E.); (M.B.); (H.P.); (H.A.)
| | - Markus Barden
- Leibniz Institute for Immunotherapy, Division of Genetic Immunotherapy, University Regensburg, 93053 Regensburg, Germany; (M.E.); (M.B.); (H.P.); (H.A.)
| | - Hong Pan
- Leibniz Institute for Immunotherapy, Division of Genetic Immunotherapy, University Regensburg, 93053 Regensburg, Germany; (M.E.); (M.B.); (H.P.); (H.A.)
| | - Wolfgang Herr
- Department of Hematology and Internal Oncology, University Hospital Regensburg, 93053 Regensburg, Germany;
| | - Hinrich Abken
- Leibniz Institute for Immunotherapy, Division of Genetic Immunotherapy, University Regensburg, 93053 Regensburg, Germany; (M.E.); (M.B.); (H.P.); (H.A.)
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2
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Montecino-Rodriguez E, Estrada OI, Dorshkind K. Transient PU.1 low fetal progenitors generate lymphoid progeny that contribute to adult immunity. Life Sci Alliance 2024; 7:e202402629. [PMID: 38830768 PMCID: PMC11147949 DOI: 10.26508/lsa.202402629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 05/22/2024] [Accepted: 05/23/2024] [Indexed: 06/05/2024] Open
Abstract
Hematopoietic stem cells and multipotential progenitors emerge in multiple, overlapping waves of fetal development. Some of these populations seed the bone marrow and sustain adult B- and T-cell development long-term after birth. However, others are present transiently, but whether they are vestigial or generate B and T cells that contribute to the adult immune system is not well understood. We now report that transient fetal progenitors distinguished by expression of low levels of the PU.1 transcription factor generated activated and memory T and B cells that colonized and were maintained in secondary lymphoid tissues. These included the small and large intestines, where they may contribute to the maintenance of gut homeostasis through at least middle age. At least some of the activated/memory cells may have been the progeny of B-1 and marginal zone B cells, as transient PU.1low fetal progenitors efficiently generated those populations. Taken together, our data demonstrate the potential of B- and T-cell progeny of transient PU.1low fetal progenitors to make an early and long-term contribution to the adult immune system.
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Affiliation(s)
- Encarnacion Montecino-Rodriguez
- https://ror.org/00mjfew53 Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Oscar I Estrada
- https://ror.org/00mjfew53 Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Kenneth Dorshkind
- https://ror.org/00mjfew53 Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
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3
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Montenegro C, Perdomo-Celis F, Franco MA. Update on Early-Life T Cells: Impact on Oral Rotavirus Vaccines. Viruses 2024; 16:818. [PMID: 38932111 PMCID: PMC11209100 DOI: 10.3390/v16060818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Revised: 05/21/2024] [Accepted: 05/21/2024] [Indexed: 06/28/2024] Open
Abstract
Rotavirus infection continues to be a significant public health problem in developing countries, despite the availability of several vaccines. The efficacy of oral rotavirus vaccines in young children may be affected by significant immunological differences between individuals in early life and adults. Therefore, understanding the dynamics of early-life systemic and mucosal immune responses and the factors that affect them is essential to improve the current rotavirus vaccines and develop the next generation of mucosal vaccines. This review focuses on the advances in T-cell development during early life in mice and humans, discussing how immune homeostasis and response to pathogens is established in this period compared to adults. Finally, the review explores how this knowledge of early-life T-cell immunity could be utilized to enhance current and novel rotavirus vaccines.
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Affiliation(s)
| | | | - Manuel A. Franco
- Instituto de Genética Humana, Facultad de Medicina, Pontificia Universidad Javeriana, Bogotá 110221, Colombia; (C.M.); (F.P.-C.)
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4
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MacNabb BW, Rothenberg EV. Speed and navigation control of thymocyte development by the fetal T-cell gene regulatory network. Immunol Rev 2023; 315:171-196. [PMID: 36722494 PMCID: PMC10771342 DOI: 10.1111/imr.13190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
T-cell differentiation is a tightly regulated developmental program governed by interactions between transcription factors (TFs) and chromatin landscapes and affected by signals received from the thymic stroma. This process is marked by a series of checkpoints: T-lineage commitment, T-cell receptor (TCR)β selection, and positive and negative selection. Dynamically changing combinations of TFs drive differentiation along the T-lineage trajectory, through mechanisms that have been most extensively dissected in adult mouse T-lineage cells. However, fetal T-cell development differs from adult in ways that suggest that these TF mechanisms are not fully deterministic. The first wave of fetal T-cell differentiation occurs during a unique developmental window during thymic morphogenesis, shows more rapid kinetics of differentiation with fewer rounds of cell division, and gives rise to unique populations of innate lymphoid cells (ILCs) and invariant γδT cells that are not generated in the adult thymus. As the characteristic kinetics and progeny biases are cell-intrinsic properties of thymic progenitors, the differences could be based on distinct TF network circuitry within the progenitors themselves. Here, we review recent single-cell transcriptome data that illuminate the TF networks involved in T-cell differentiation in the fetal and adult mouse thymus.
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Affiliation(s)
- Brendan W MacNabb
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, California, USA
| | - Ellen V Rothenberg
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, California, USA
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5
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The β-selection step shapes T-cell identity. Nature 2023; 613:440-442. [PMID: 36646871 DOI: 10.1038/d41586-023-00025-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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6
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Abstract
Traditional models of lymphopoiesis present B and T cell development as a linear process that initiates in the fetus and continues after birth in the bone marrow and thymus, respectively. However, this view of lymphocyte development is not in accord with reports, dating back several decades, indicating that the types of lymphocytes generated before and after birth differ. In this regard, selected γδ T cells, and those that utilize the Vγ3 receptor in particular, and innate-like B-1 B cells preferentially arise during fetal blood cell development. This review synthesizes data from multiple laboratories, with an emphasis on our own work using mouse models, demonstrating that innate and conventional B and T cells emerge in hematopoietic stem cell independent and dependent waves of development that are differentially regulated. This layering of lymphocyte development has implications for understanding the composition of the adult immune system and may provide insights into the origin of various lymphocytic leukemias.
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Affiliation(s)
- Encarnacion Montecino-Rodriguez
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, USA
| | - Kenneth Dorshkind
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, USA
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7
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Hosokawa H, Koizumi M, Masuhara K, Romero-Wolf M, Tanaka T, Nakayama T, Rothenberg EV. Stage-specific action of Runx1 and GATA3 controls silencing of PU.1 expression in mouse pro-T cells. J Exp Med 2021; 218:e20202648. [PMID: 34180951 PMCID: PMC8241539 DOI: 10.1084/jem.20202648] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 05/01/2021] [Accepted: 06/10/2021] [Indexed: 12/16/2022] Open
Abstract
PU.1 (encoded by Spi1), an ETS-family transcription factor with many hematopoietic roles, is highly expressed in the earliest intrathymic T cell progenitors but must be down-regulated during T lineage commitment. The transcription factors Runx1 and GATA3 have been implicated in this Spi1 repression, but the basis of the timing was unknown. We show that increasing Runx1 and/or GATA3 down-regulates Spi1 expression in pro-T cells, while deletion of these factors after Spi1 down-regulation reactivates its expression. Leveraging the stage specificities of repression and transcription factor binding revealed an unconventional but functional site in Spi1 intron 2. Acute Cas9-mediated deletion or disruption of the Runx and GATA motifs in this element reactivates silenced Spi1 expression in a pro-T cell line, substantially more than disruption of other candidate elements, and counteracts the repression of Spi1 in primary pro-T cells during commitment. Thus, Runx1 and GATA3 work stage specifically through an intronic silencing element in mouse Spi1 to control strength and maintenance of Spi1 repression during T lineage commitment.
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Affiliation(s)
- Hiroyuki Hosokawa
- Department of Immunology, Tokai University School of Medicine, Isehara, Kanagawa, Japan
- Institute of Medical Sciences, Tokai University, Isehara, Kanagawa, Japan
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA
| | - Maria Koizumi
- Department of Immunology, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Kaori Masuhara
- Department of Immunology, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Maile Romero-Wolf
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA
| | - Tomoaki Tanaka
- Department of Molecular Diagnosis, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba, Japan
| | - Toshinori Nakayama
- Department of Immunology, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba, Japan
| | - Ellen V Rothenberg
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA
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8
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Ding J, Cardoso AA, Yoshimoto M, Kobayashi M. The Earliest T-Precursors in the Mouse Embryo Are Susceptible to Leukemic Transformation. Front Cell Dev Biol 2021; 9:634151. [PMID: 33996794 PMCID: PMC8117020 DOI: 10.3389/fcell.2021.634151] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 04/06/2021] [Indexed: 11/13/2022] Open
Abstract
Acute lymphoblastic leukemia (ALL) is the most common malignancy in pediatric patients. About 10–15% of pediatric ALL belong to T-cell ALL (T-ALL), which is characterized by aggressive expansion of immature T-lymphoblasts and is categorized as high-risk leukemia. Leukemia initiating cells represent a reservoir that is responsible for the initiation and propagation of leukemia. Its perinatal origin has been suggested in some childhood acute B-lymphoblastic and myeloblastic leukemias. Therefore, we hypothesized that child T-ALL initiating cells also exist during the perinatal period. In this study, T-ALL potential of the hematopoietic precursors was found in the para-aortic splanchnopleura (P-Sp) region, but not in the extraembryonic yolk sac (YS) of the mouse embryo at embryonic day 9.5. We overexpressed the Notch intracellular domain (NICD) in the P-Sp and YS cells and transplanted them into lethally irradiated mice. NICD-overexpressing P-Sp cells rapidly developed T-ALL while YS cells failed to display leukemia propagation despite successful NICD induction. These results suggest a possible role of fetal-derived T-cell precursors as leukemia-initiating cells.
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Affiliation(s)
- Jixin Ding
- Department of Medicine, Melvin and Bren Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Angelo A Cardoso
- Department of Medicine, Melvin and Bren Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN, United States.,Beckman Research Institute, City of Hope National Medical Center, Duarte, CA, United States
| | - Momoko Yoshimoto
- Department of Pediatrics Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, United States.,Center for Stem Cell and Regenerative Medicine, Institute of Molecular Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Michihiro Kobayashi
- Department of Pediatrics Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, United States.,Center for Stem Cell and Regenerative Medicine, Institute of Molecular Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, United States
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9
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Bunis DG, Bronevetsky Y, Krow-Lucal E, Bhakta NR, Kim CC, Nerella S, Jones N, Mendoza VF, Bryson YJ, Gern JE, Rutishauser RL, Ye CJ, Sirota M, McCune JM, Burt TD. Single-Cell Mapping of Progressive Fetal-to-Adult Transition in Human Naive T Cells. Cell Rep 2021; 34:108573. [PMID: 33406429 PMCID: PMC10263444 DOI: 10.1016/j.celrep.2020.108573] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 06/01/2020] [Accepted: 12/08/2020] [Indexed: 12/12/2022] Open
Abstract
Whereas the human fetal immune system is poised to generate immune tolerance and suppress inflammation in utero, an adult-like immune system emerges to orchestrate anti-pathogen immune responses in post-natal life. It has been posited that cells of the adult immune system arise as a discrete ontological "layer" of hematopoietic stem-progenitor cells (HSPCs) and their progeny; evidence supporting this model in humans has, however, been inconclusive. Here, we combine bulk and single-cell transcriptional profiling of lymphoid cells, myeloid cells, and HSPCs from fetal, perinatal, and adult developmental stages to demonstrate that the fetal-to-adult transition occurs progressively along a continuum of maturity-with a substantial degree of inter-individual variation at the time of birth-rather than via a transition between discrete waves. These findings have important implications for the design of strategies for prophylaxis against infection in the newborn and for the use of umbilical cord blood (UCB) in the setting of transplantation.
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Affiliation(s)
- Daniel G Bunis
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA; Bakar Computational Health Sciences Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Yelena Bronevetsky
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, USA
| | - Elisabeth Krow-Lucal
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, USA
| | - Nirav R Bhakta
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, USA
| | - Charles C Kim
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, USA
| | - Srilaxmi Nerella
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, USA
| | - Norman Jones
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA; Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, USA
| | - Ventura F Mendoza
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA; Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, USA
| | - Yvonne J Bryson
- Division of Pediatric Infectious Diseases, Department of Pediatrics, David Geffen School of Medicine at UCLA, Mattel Children's Hospital UCLA, Los Angeles, CA, USA
| | - James E Gern
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Rachel L Rutishauser
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, USA
| | - Chun Jimmie Ye
- Bakar Computational Health Sciences Institute, University of California, San Francisco, San Francisco, CA, USA; Institute for Human Genetics, University of California, San Francisco, San Francisco, CA, USA; Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA, USA; Division of Rheumatology, Department of Medicine, University of California, San Francisco, San Francisco, CA, USA; Parker Institute for Cancer Immunotherapy, San Francisco, CA, USA; Chan Zuckerberg Biohub, San Francisco, CA, USA
| | - Marina Sirota
- Bakar Computational Health Sciences Institute, University of California, San Francisco, San Francisco, CA, USA; Department of Pediatrics, Division of Neonatology, University of California, San Francisco, San Francisco, CA, USA.
| | - Joseph M McCune
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, USA.
| | - Trevor D Burt
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA; Department of Pediatrics, Division of Neonatology, University of California, San Francisco, San Francisco, CA, USA.
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10
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Anderson MK, Selvaratnam JS. Interaction between γδTCR signaling and the E protein-Id axis in γδ T cell development. Immunol Rev 2020; 298:181-197. [PMID: 33058287 DOI: 10.1111/imr.12924] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 08/24/2020] [Accepted: 08/28/2020] [Indexed: 02/06/2023]
Abstract
γδ T cells acquire their functional properties in the thymus, enabling them to exert rapid innate-like responses. To understand how distinct γδ T cell subsets are generated, we have developed a Two-Stage model for γδ T cell development. This model is predicated on the finding that γδTCR signal strength impacts E protein activity through graded upregulation of Id3. Our model proposes that cells enter Stage 1 in response to a γδTCR signaling event in the cortex that activates a γδ T cell-specific gene network. Part of this program includes the upregulation of chemokine receptors that guide them to the medulla. In the medulla, Stage 1 cells receive distinct combinations of γδTCR, cytokine, and/co-stimulatory signals that induce their transit into Stage 2, either toward the γδT1 or the γδT17 lineage. The intersection between γδTCR and cytokine signals can tune Id3 expression, leading to different outcomes even in the presence of strong γδTCR signals. The thymic signaling niches required for γδT17 development are segregated in time and space, providing transient windows of opportunity during ontogeny. Understanding the regulatory context in which E proteins operate at different stages will be key in defining how their activity levels impose functional outcomes.
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Affiliation(s)
- Michele K Anderson
- Biological Sciences, Sunnybrook Research Institute, Toronto, ON, Canada.,Department of Immunology, University of Toronto, Toronto, ON, Canada
| | - Johanna S Selvaratnam
- Biological Sciences, Sunnybrook Research Institute, Toronto, ON, Canada.,Department of Immunology, University of Toronto, Toronto, ON, Canada
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11
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Rothenberg EV, Hosokawa H, Ungerbäck J. Mechanisms of Action of Hematopoietic Transcription Factor PU.1 in Initiation of T-Cell Development. Front Immunol 2019; 10:228. [PMID: 30842770 PMCID: PMC6391351 DOI: 10.3389/fimmu.2019.00228] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 01/28/2019] [Indexed: 12/20/2022] Open
Abstract
PU.1 is an ETS-family transcription factor that plays a broad range of roles in hematopoiesis. A direct regulator of myeloid, dendritic-cell, and B cell functional programs, and a well-known antagonist of terminal erythroid cell differentiation, it is also expressed in the earliest stages of T-cell development of each cohort of intrathymic pro-T cells. Its expression in this context appears to give T-cell precursors initial, transient access to myeloid and dendritic cell developmental competence and therefore to represent a source of antagonism or delay of T-cell lineage commitment. However, it has remained uncertain until recently why T-cell development is also intensely dependent upon PU.1. Here, we review recent work that sheds light on the molecular biology of PU.1 action across the genome in pro-T cells and identifies the genes that depend on PU.1 for their correct regulation. This work indicates modes of chromatin engagement, pioneering, and cofactor recruitment (“coregulator theft”) by PU.1 as well as gene network interactions that not only affect specific target genes but also have system-wide regulatory consequences, amplifying the impact of PU.1 beyond its own direct binding targets. The genes directly regulated by PU.1 also suggest a far-reaching transformation of cell biology and signaling potential between the early stages of T-cell development when PU.1 is expressed and when it is silenced. These cell-biological functions can be important to distinguish fetal from adult T-cell development and have the potential to illuminate aspects of thymic function that have so far remained the most mysterious.
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Affiliation(s)
- Ellen V Rothenberg
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Hiroyuki Hosokawa
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Jonas Ungerbäck
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
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