1
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Weaver SR, Peralta-Herrera E, Torres HM, Jessen E, Bradley EW, Westendorf JJ. Phlpp1 alters the murine chondrocyte phospho-proteome during endochondral bone formation. Bone 2024; 189:117265. [PMID: 39349089 DOI: 10.1016/j.bone.2024.117265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2024] [Revised: 09/19/2024] [Accepted: 09/25/2024] [Indexed: 10/02/2024]
Abstract
Appendicular skeletal growth and bone mass acquisition are controlled by a variety of growth factors, hormones, and mechanical forces in a dynamic process called endochondral ossification. In long bones, chondrocytes in the growth plate proliferate and undergo hypertrophy to drive bone lengthening and mineralization. Pleckstrin homology (PH) domain and leucine rich repeat phosphatase 1 and 2 (Phlpp1 and Phlpp2) are serine/threonine protein phosphatases that regulate cell proliferation, survival, and maturation via Akt, PKC, Raf1, S6k, and other intracellular signaling cascades. Germline deletion of Phlpp1 suppresses bone lengthening in growth plate chondrocytes. Here, we demonstrate that Phlpp2 does not regulate endochondral ossification, and we define the molecular differences between Phlpp1 and Phlpp2 in chondrocytes. Phlpp2-/- mice were phenotypically indistinguishable from their wildtype (WT) littermates, with similar bone length, bone mass, and growth plate dynamics. Deletion of Phlpp2 had moderate effects on the chondrocyte transcriptome and proteome compared to WT cells. By contrast, Phlpp1/2-/- (double knockout) mice resembled Phlpp1-/- mice phenotypically and molecularly, as the chondrocyte phospho-proteomes of Phlpp1-/- and Phlpp1/2-/- chondrocytes had similarities and were significantly different from WT and Phlpp2-/- chondrocyte phospho-proteomes. Data integration via multiparametric analysis showed that the transcriptome explained less variation in the data as a result of Phlpp1 or Phlpp2 deletion than proteome or phospho-proteome. Alterations in cell proliferation, collagen fibril organization, and Pdpk1 and Pak1/2 signaling pathways were identified in chondrocytes lacking Phlpp1, while cell cycle processes and Akt1 and Aurka signaling pathways were altered in chondrocytes lacking Phlpp2. These data demonstrate that Phlpp1, and to a lesser extent Phlpp2, regulate multiple and complex signaling cascades across the chondrocyte transcriptome, proteome, and phospho-proteome and that multi-omic data integration can reveal novel putative kinase targets that regulate endochondral ossification.
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Affiliation(s)
- Samantha R Weaver
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, United States of America
| | | | - Haydee M Torres
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, United States of America
| | - Erik Jessen
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN, United States of America
| | - Elizabeth W Bradley
- Department of Orthopedics, School of Medicine, University of Minnesota, Minneapolis, MN, United States of America
| | - Jennifer J Westendorf
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, United States of America; Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States of America.
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2
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Kennedy PH, Alborzian Deh Sheikh A, Balakar M, Jones AC, Olive ME, Hegde M, Matias MI, Pirete N, Burt R, Levy J, Little T, Hogan PG, Liu DR, Doench JG, Newton AC, Gottschalk RA, de Boer CG, Alarcón S, Newby GA, Myers SA. Post-translational modification-centric base editor screens to assess phosphorylation site functionality in high throughput. Nat Methods 2024; 21:1033-1043. [PMID: 38684783 DOI: 10.1038/s41592-024-02256-z] [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: 10/16/2023] [Accepted: 03/20/2024] [Indexed: 05/02/2024]
Abstract
Signaling pathways that drive gene expression are typically depicted as having a dozen or so landmark phosphorylation and transcriptional events. In reality, thousands of dynamic post-translational modifications (PTMs) orchestrate nearly every cellular function, and we lack technologies to find causal links between these vast biochemical pathways and genetic circuits at scale. Here we describe the high-throughput, functional assessment of phosphorylation sites through the development of PTM-centric base editing coupled to phenotypic screens, directed by temporally resolved phosphoproteomics. Using T cell activation as a model, we observe hundreds of unstudied phosphorylation sites that modulate NFAT transcriptional activity. We identify the phosphorylation-mediated nuclear localization of PHLPP1, which promotes NFAT but inhibits NFκB activity. We also find that specific phosphosite mutants can alter gene expression in subtle yet distinct patterns, demonstrating the potential for fine-tuning transcriptional responses. Overall, base editor screening of PTM sites provides a powerful platform to dissect PTM function within signaling pathways.
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Affiliation(s)
- Patrick H Kennedy
- Laboratory for Immunochemical Circuits, La Jolla Institute for Immunology, La Jolla, CA, USA
- Center of Autoimmunity and Inflammation, La Jolla Institute for Immunology, La Jolla, CA, USA
- Division of Signaling and Gene Expression, La Jolla Institute for Immunology, La Jolla, CA, USA
| | - Amin Alborzian Deh Sheikh
- Laboratory for Immunochemical Circuits, La Jolla Institute for Immunology, La Jolla, CA, USA
- Center of Autoimmunity and Inflammation, La Jolla Institute for Immunology, La Jolla, CA, USA
- Division of Signaling and Gene Expression, La Jolla Institute for Immunology, La Jolla, CA, USA
| | | | - Alexander C Jones
- Department of Pharmacology, University of California San Diego, San Diego, CA, USA
- Biomedical Sciences Graduate Program, University of California San Diego, San Diego, CA, USA
| | | | - Mudra Hegde
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Maria I Matias
- Laboratory for Immunochemical Circuits, La Jolla Institute for Immunology, La Jolla, CA, USA
- Center of Autoimmunity and Inflammation, La Jolla Institute for Immunology, La Jolla, CA, USA
- Division of Signaling and Gene Expression, La Jolla Institute for Immunology, La Jolla, CA, USA
| | - Natan Pirete
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Rajan Burt
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Jonathan Levy
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - Tamia Little
- Laboratory for Immunochemical Circuits, La Jolla Institute for Immunology, La Jolla, CA, USA
- Center of Autoimmunity and Inflammation, La Jolla Institute for Immunology, La Jolla, CA, USA
- Division of Signaling and Gene Expression, La Jolla Institute for Immunology, La Jolla, CA, USA
| | - Patrick G Hogan
- Division of Signaling and Gene Expression, La Jolla Institute for Immunology, La Jolla, CA, USA
- Program in Immunology, University of California San Diego, San Diego, CA, USA
- Moores Cancer Center, University of California San Diego Health, La Jolla, CA, USA
| | - David R Liu
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - John G Doench
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Alexandra C Newton
- Department of Pharmacology, University of California San Diego, San Diego, CA, USA
| | - Rachel A Gottschalk
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Carl G de Boer
- School of Biomedical Engineering, University of British Columbia, Vancouver, British Columbia, Canada
| | - Suzie Alarcón
- La Jolla Institute for Immunology, La Jolla, CA, USA
- AUGenomics, San Diego, CA, USA
| | - Gregory A Newby
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Samuel A Myers
- Laboratory for Immunochemical Circuits, La Jolla Institute for Immunology, La Jolla, CA, USA.
- Center of Autoimmunity and Inflammation, La Jolla Institute for Immunology, La Jolla, CA, USA.
- Division of Signaling and Gene Expression, La Jolla Institute for Immunology, La Jolla, CA, USA.
- Department of Pharmacology, University of California San Diego, San Diego, CA, USA.
- Program in Immunology, University of California San Diego, San Diego, CA, USA.
- Moores Cancer Center, University of California San Diego Health, La Jolla, CA, USA.
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3
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Kennedy PH, Deh Sheikh AA, Balakar M, Jones AC, Olive ME, Hegde M, Matias MI, Pirete N, Burt R, Levy J, Little T, Hogan PG, Liu DR, Doench JG, Newton AC, Gottschalk RA, de Boer C, Alarcón S, Newby G, Myers SA. Proteome-wide base editor screens to assess phosphorylation site functionality in high-throughput. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.11.566649. [PMID: 38014346 PMCID: PMC10680671 DOI: 10.1101/2023.11.11.566649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Signaling pathways that drive gene expression are typically depicted as having a dozen or so landmark phosphorylation and transcriptional events. In reality, thousands of dynamic post-translational modifications (PTMs) orchestrate nearly every cellular function, and we lack technologies to find causal links between these vast biochemical pathways and genetic circuits at scale. Here, we describe "signaling-to-transcription network" mapping through the development of PTM-centric base editing coupled to phenotypic screens, directed by temporally-resolved phosphoproteomics. Using T cell activation as a model, we observe hundreds of unstudied phosphorylation sites that modulate NFAT transcriptional activity. We identify the phosphorylation-mediated nuclear localization of the phosphatase PHLPP1 which promotes NFAT but inhibits NFκB activity. We also find that specific phosphosite mutants can alter gene expression in subtle yet distinct patterns, demonstrating the potential for fine-tuning transcriptional responses. Overall, base editor screening of PTM sites provides a powerful platform to dissect PTM function within signaling pathways.
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4
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Bulygin AS, Khantakova JN, Shkaruba NS, Shiku H, Sennikov SS. The role of metabolism on regulatory T cell development and its impact in tumor and transplantation immunity. Front Immunol 2022; 13:1016670. [PMID: 36569866 PMCID: PMC9767971 DOI: 10.3389/fimmu.2022.1016670] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 11/21/2022] [Indexed: 12/12/2022] Open
Abstract
Regulatory CD4+ T (Treg) cells play a key role in the induction of immune tolerance and in the prevention of autoimmune diseases. Treg cells are defined by the expression of transcription factor FOXP3, which ensures proliferation and induction of the suppressor activity of this cell population. In a tumor microenvironment, after transplantation or during autoimmune diseases, Treg cells can respond to various signals from their environment and this property ensures their suppressor function. Recent studies showed that a metabolic signaling pathway of Treg cells are essential in the control of Treg cell proliferation processes. This review presents the latest research highlights on how the influence of extracellular factors (e.g. nutrients, vitamins and metabolites) as well as intracellular metabolic signaling pathways regulate tissue specificity of Treg cells and heterogeneity of this cell population. Understanding the metabolic regulation of Treg cells should provide new insights into immune homeostasis and disorders along with important therapeutic implications for autoimmune diseases, cancer and other immune-system-mediated disorders.
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5
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Balamurugan K, Chandra K, Sai Latha S, Swathi M, Joshi MB, Misra P, Parsa KVL. PHLPPs: Emerging players in metabolic disorders. Drug Discov Today 2022; 27:103317. [PMID: 35835313 DOI: 10.1016/j.drudis.2022.07.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 06/21/2022] [Accepted: 07/07/2022] [Indexed: 12/15/2022]
Abstract
That reversible protein phosphorylation by kinases and phosphatases occurs in metabolic disorders is well known. Various studies have revealed that a multi-faceted and tightly regulated phosphatase, pleckstrin homology domain leucine-rich repeat protein phosphatase (PHLPP)-1/2 displays robust effects in cardioprotection, ischaemia/reperfusion (I/R), and vascular remodelling. PHLPP1 promotes foamy macrophage development through ChREBP/AMPK-dependent pathways. Adipocyte-specific loss of PHLPP2 reduces adiposity, improves glucose tolerance,and attenuates fatty liver via the PHLPP2-HSL-PPARα axis. Discoveries of PHLPP1-mediated insulin resistance and pancreatic β cell death via the PHLPP1/2-Mst1-mTORC1 triangular loop have shed light on its significance in diabetology. PHLPP1 downregulation attenuates diabetic cardiomyopathy (DCM) by restoring PI3K-Akt-mTOR signalling. In this review, we summarise the functional role of, and cellular signalling mediated by, PHLPPs in metabolic tissues and discuss their potential as therapeutic targets.
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Affiliation(s)
- Keerthana Balamurugan
- Center for Innovation in Molecular and Pharmaceutical Sciences (CIMPS), Dr. Reddy's Institute of Life Sciences (DRILS), University of Hyderabad Campus, Hyderabad 500046, Telangana, India; Department of Ageing Research, Manipal School of Life Sciences, Manipal Academy of Higher Education (MAHE), Manipal 576104, Karnataka, India
| | - Kanika Chandra
- Center for Innovation in Molecular and Pharmaceutical Sciences (CIMPS), Dr. Reddy's Institute of Life Sciences (DRILS), University of Hyderabad Campus, Hyderabad 500046, Telangana, India; Department of Ageing Research, Manipal School of Life Sciences, Manipal Academy of Higher Education (MAHE), Manipal 576104, Karnataka, India
| | - S Sai Latha
- Center for Innovation in Molecular and Pharmaceutical Sciences (CIMPS), Dr. Reddy's Institute of Life Sciences (DRILS), University of Hyderabad Campus, Hyderabad 500046, Telangana, India
| | - M Swathi
- Center for Innovation in Molecular and Pharmaceutical Sciences (CIMPS), Dr. Reddy's Institute of Life Sciences (DRILS), University of Hyderabad Campus, Hyderabad 500046, Telangana, India
| | - Manjunath B Joshi
- Department of Ageing Research, Manipal School of Life Sciences, Manipal Academy of Higher Education (MAHE), Manipal 576104, Karnataka, India
| | - Parimal Misra
- Center for Innovation in Molecular and Pharmaceutical Sciences (CIMPS), Dr. Reddy's Institute of Life Sciences (DRILS), University of Hyderabad Campus, Hyderabad 500046, Telangana, India
| | - Kishore V L Parsa
- Center for Innovation in Molecular and Pharmaceutical Sciences (CIMPS), Dr. Reddy's Institute of Life Sciences (DRILS), University of Hyderabad Campus, Hyderabad 500046, Telangana, India.
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6
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Guerau-de-Arellano M, Piedra-Quintero ZL, Tsichlis PN. Akt isoforms in the immune system. Front Immunol 2022; 13:990874. [PMID: 36081513 PMCID: PMC9445622 DOI: 10.3389/fimmu.2022.990874] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Accepted: 08/04/2022] [Indexed: 11/29/2022] Open
Abstract
Akt is a PI3K-activated serine-threonine kinase that exists in three distinct isoforms. Akt's expression in most immune cells, either at baseline or upon activation, reflects its importance in the immune system. While Akt is most highly expressed in innate immune cells, it plays crucial roles in both innate and adaptive immune cell development and/or effector functions. In this review, we explore what's known about the role of Akt in innate and adaptive immune cells. Wherever possible, we discuss the overlapping and distinct role of the three Akt isoforms, namely Akt1, Akt2, and Akt3, in immune cells.
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Affiliation(s)
- Mireia Guerau-de-Arellano
- School of Health and Rehabilitation Sciences, Division of Medical Laboratory Science, College of Medicine, Wexner Medical Center, The Ohio State University, Columbus, OH, United States,Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, United States,Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, United States,Department of Neuroscience, The Ohio State University, Columbus, OH, United States,The Ohio State University Comprehensive Cancer Center, The Ohio State University, Columbus, OH, United States,*Correspondence: Mireia Guerau-de-Arellano,
| | - Zayda L. Piedra-Quintero
- School of Health and Rehabilitation Sciences, Division of Medical Laboratory Science, College of Medicine, Wexner Medical Center, The Ohio State University, Columbus, OH, United States
| | - Philip N. Tsichlis
- The Ohio State University Comprehensive Cancer Center, The Ohio State University, Columbus, OH, United States,Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, United States
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7
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Chowdhury S, Kar A, Bhowmik D, Gautam A, Basak D, Sarkar I, Ghosh P, Sarkar D, Deka A, Chakraborty P, Mukhopadhyay A, Mehrotra S, Basak S, Paul S, Chatterjee S. Intracellular Acetyl CoA Potentiates the Therapeutic Efficacy of Antitumor CD8+ T Cells. Cancer Res 2022; 82:2640-2655. [PMID: 35648389 PMCID: PMC7613107 DOI: 10.1158/0008-5472.can-21-4052] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 04/20/2022] [Accepted: 05/20/2022] [Indexed: 01/09/2023]
Abstract
Effector CD8+ T cells rely primarily on glucose metabolism to meet their biosynthetic and functional needs. However, nutritional limitations in the tumor microenvironment can cause T-cell hyporesponsiveness. Therefore, T cells must acquire metabolic traits enabling sustained effector function at the tumor site to elicit a robust antitumor immune response. Here, we report that IL12-stimulated CD8+ T cells have elevated intracellular acetyl CoA levels and can maintain IFNγ levels in nutrient-deprived, tumor-conditioned media (TCM). Pharmacological and metabolic analyses demonstrated an active glucose-citrate-acetyl CoA circuit in IL12-stimulated CD8+ T cells supporting an intracellular pool of acetyl CoA in an ATP-citrate lyase (ACLY)-dependent manner. Intracellular acetyl CoA levels enhanced histone acetylation, lipid synthesis, and IFNγ production, improving the metabolic and functional fitness of CD8+ T cells in tumors. Pharmacological inhibition or genetic knockdown of ACLY severely impaired IFNγ production and viability of CD8+ T cells in nutrient-restricted conditions. Furthermore, CD8+ T cells cultured in high pyruvate-containing media in vitro acquired critical metabolic features of IL12-stimulated CD8+ T cells and displayed improved antitumor potential upon adoptive transfer in murine lymphoma and melanoma models. Overall, this study delineates the metabolic configuration of CD8+ T cells required for stable effector function in tumors and presents an affordable approach to promote the efficacy of CD8+ T cells for adoptive T-cell therapy. SIGNIFICANCE IL12-mediated metabolic reprogramming increases intracellular acetyl CoA to promote the effector function of CD8+ T cells in nutrient-depleted tumor microenvironments, revealing strategies to potentiate the antitumor efficacy of T cells.
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Affiliation(s)
- Snehanshu Chowdhury
- Division of Cancer Biology and Inflammatory Disorder, IICB-Translational Research Unit of Excellence, CSIR-Indian Institute of Chemical Biology, Kolkata, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Anwesha Kar
- Division of Cancer Biology and Inflammatory Disorder, IICB-Translational Research Unit of Excellence, CSIR-Indian Institute of Chemical Biology, Kolkata, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Debaleena Bhowmik
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.,Division of Structural Biology and Bioinformatics, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Anupam Gautam
- Institute for Bioinformatics and Medical Informatics, University of Tübingen, Tübingen, Germany.,International Max Planck Research School “From Molecules to Organisms,” Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Debashree Basak
- Division of Cancer Biology and Inflammatory Disorder, IICB-Translational Research Unit of Excellence, CSIR-Indian Institute of Chemical Biology, Kolkata, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Ishita Sarkar
- Division of Cancer Biology and Inflammatory Disorder, IICB-Translational Research Unit of Excellence, CSIR-Indian Institute of Chemical Biology, Kolkata, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Puspendu Ghosh
- Division of Cancer Biology and Inflammatory Disorder, IICB-Translational Research Unit of Excellence, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Deborpita Sarkar
- Division of Cancer Biology and Inflammatory Disorder, IICB-Translational Research Unit of Excellence, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Alvina Deka
- System Immunology Laboratory, National Institute of Immunology, New Delhi, India
| | - Paramita Chakraborty
- Department of Surgery, Medical University of South Carolina, South Carolina, Charleston
| | - Asima Mukhopadhyay
- Department of Gynecological Oncology, Chittaranjan National Cancer Institute, Kolkata, India
| | - Shikhar Mehrotra
- Department of Surgery, Medical University of South Carolina, South Carolina, Charleston
| | - Soumen Basak
- System Immunology Laboratory, National Institute of Immunology, New Delhi, India
| | - Sandip Paul
- Center for Health Science and Technology, JIS Institute of Advanced Studies and Research, JIS University, Kolkata, India
| | - Shilpak Chatterjee
- Division of Cancer Biology and Inflammatory Disorder, IICB-Translational Research Unit of Excellence, CSIR-Indian Institute of Chemical Biology, Kolkata, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.,Corresponding Author: Shilpak Chatterjee, CSIR-Indian Institute of Chemical Biology, 4 Raja S.C Mallick Road, Kolkata 700032, India. Phone: 33-2499-5700, ext. 3013; E-mail:
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8
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Lam AJ, Haque M, Ward-Hartstonge KA, Uday P, Wardell CM, Gillies JK, Speck M, Mojibian M, Klein Geltink RI, Levings MK. PTEN is required for human Treg suppression of costimulation in vitro. Eur J Immunol 2022; 52:1482-1497. [PMID: 35746855 DOI: 10.1002/eji.202249888] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 05/18/2022] [Accepted: 06/10/2022] [Indexed: 11/07/2022]
Abstract
Regulatory T cell (Treg) therapy is under clinical investigation for the treatment of transplant rejection, autoimmune disease, and graft-versus-host disease. With the advent of genome editing, attention has turned to reinforcing Treg function for therapeutic benefit. A hallmark of Tregs is dampened activation of PI3K-AKT signalling, of which PTEN is a major negative regulator. Loss-of-function studies of PTEN, however, have not conclusively shown a requirement for PTEN in upholding Treg function and stability. Using CRISPR-based genome editing in human Tregs, we show that PTEN ablation does not cause a global defect in Treg function and stability; rather, it selectively blocks their ability to suppress antigen-presenting cells. PTEN-KO Tregs exhibit elevated glycolytic activity, upregulate FOXP3, maintain a Treg phenotype, and have no discernable defects in lineage stability. Functionally, PTEN is dispensable for human Treg-mediated inhibition of T cell activity in vitro and in vivo, but is required for suppression of costimulatory molecule expression by antigen-presenting cells. These data are the first to define a role for a signalling pathway in controlling a subset of human Treg activity. Moreover, they point to the functional necessity of PTEN-regulated PI3K-AKT activity for optimal human Treg function. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Avery J Lam
- BC Children's Hospital Research Institute, Vancouver, BC, V5Z 4H4, Canada.,Department of Surgery, University of British Columbia, Vancouver, BC, V5Z 1M9, Canada
| | - Manjurul Haque
- BC Children's Hospital Research Institute, Vancouver, BC, V5Z 4H4, Canada.,Department of Surgery, University of British Columbia, Vancouver, BC, V5Z 1M9, Canada
| | - Kirsten A Ward-Hartstonge
- BC Children's Hospital Research Institute, Vancouver, BC, V5Z 4H4, Canada.,Department of Surgery, University of British Columbia, Vancouver, BC, V5Z 1M9, Canada
| | - Prakruti Uday
- BC Children's Hospital Research Institute, Vancouver, BC, V5Z 4H4, Canada.,Department of Surgery, University of British Columbia, Vancouver, BC, V5Z 1M9, Canada
| | - Christine M Wardell
- BC Children's Hospital Research Institute, Vancouver, BC, V5Z 4H4, Canada.,Department of Surgery, University of British Columbia, Vancouver, BC, V5Z 1M9, Canada
| | - Jana K Gillies
- BC Children's Hospital Research Institute, Vancouver, BC, V5Z 4H4, Canada.,Department of Surgery, University of British Columbia, Vancouver, BC, V5Z 1M9, Canada
| | - Madeleine Speck
- BC Children's Hospital Research Institute, Vancouver, BC, V5Z 4H4, Canada.,Department of Surgery, University of British Columbia, Vancouver, BC, V5Z 1M9, Canada
| | - Majid Mojibian
- BC Children's Hospital Research Institute, Vancouver, BC, V5Z 4H4, Canada.,Department of Surgery, University of British Columbia, Vancouver, BC, V5Z 1M9, Canada
| | - Ramon I Klein Geltink
- BC Children's Hospital Research Institute, Vancouver, BC, V5Z 4H4, Canada.,Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, V6T 2B5, Canada.,Department of Molecular Oncology, BC Cancer Research, Vancouver, BC, V5Z 1L3, Canada
| | - Megan K Levings
- BC Children's Hospital Research Institute, Vancouver, BC, V5Z 4H4, Canada.,Department of Surgery, University of British Columbia, Vancouver, BC, V5Z 1M9, Canada.,School of Biomedical Engineering, University of British Columbia, Vancouver, V6T 1Z3, Canada
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9
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Signaling pathway(s) of TNFR2 required for the immunoregulatory effect of CD4 +Foxp3 + regulatory T cells. Int Immunopharmacol 2022; 108:108823. [PMID: 35623290 DOI: 10.1016/j.intimp.2022.108823] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 04/26/2022] [Accepted: 04/29/2022] [Indexed: 11/23/2022]
Abstract
CD4+Foxp3+ regulatory T cells (Tregs), a subpopulation of CD4+ T cells, are engaged in maintaining the periphery tolerance and preventing autoimmunity. Recent studies showed that tumor necrosis factor receptor 2 (TNFR2) is preferentially expressed by Tregs and the expression of this receptor identifies the maximally suppressive Tregs. That is, TNFR2 is a liable phenotypic and functional surface marker of Tregs. Moreover, TNF activates and expands Tregs through TNFR2. However, it is very interesting which signaling pathway(s) of TNFR2 is required for the inhibitory effect of Tregs. Compelling evidence shows three TNFR2 signaling pathways in Tregs, including NF-κB, MAPK and PI3K-Akt pathways. Here, we summarize and discuss the latest progress in the studies on the downstream signaling pathways of TNF-TNFR2 for controlling Treg homeostasis, differentiation and proliferation.
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10
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Tiwari D, Ahuja N, Kumar S, Kalra R, Nanduri R, Gupta S, Khare AK, Bhagyaraj E, Arora R, Gupta P. Nuclear receptor Nr1d1 alleviates asthma by abating GATA3 gene expression and Th2 cell differentiation. Cell Mol Life Sci 2022; 79:308. [PMID: 35596832 PMCID: PMC11073070 DOI: 10.1007/s00018-022-04323-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 03/30/2022] [Accepted: 04/21/2022] [Indexed: 11/03/2022]
Abstract
Nuclear receptors are a unique family of transcription factors that play cardinal roles in physiology and plethora of human diseases. The adopted orphan nuclear receptor Nr1d1 is a constitutive transcriptional repressor known to modulate several biological processes. In this study, we found that Nr1d1 plays a decisive role in T helper (Th)-cell polarization and transcriptionally impedes the formation of Th2 cells by directly binding to the promoter region of GATA binding protein 3 (GATA3) gene. Nr1d1 interacts with its cellular companion, the nuclear receptor corepressor and histone deacetylase 3 to form a stable repression complex on the GATA3 promoter. The presence of Nr1d1 also imparts protection against associated inflammatory responses in murine model of asthma and its ligand SR9011 eased disease severity by suppressing Th2 responses. Moreover, Chip-seq profiling uncovered Nr1d1 interactions with other gene subsets that impedes Th2-linked pathways and regulates metabolism, immunity and brain functions, therefore, providing empirical evidence regarding the genetic link between asthma and other comorbid conditions. Thus, Nr1d1 emerges as a molecular switch that could be targeted to subdue asthma.
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Affiliation(s)
- Drishti Tiwari
- Department of Molecular Immunology, Council of Scientific and Industrial Research, Institute of Microbial Technology, Sector 39A, Chandigarh, 160036, India.
| | - Nancy Ahuja
- Department of Molecular Immunology, Council of Scientific and Industrial Research, Institute of Microbial Technology, Sector 39A, Chandigarh, 160036, India
| | - Sumit Kumar
- Department of Molecular Immunology, Council of Scientific and Industrial Research, Institute of Microbial Technology, Sector 39A, Chandigarh, 160036, India
| | - Rashi Kalra
- Department of Molecular Immunology, Council of Scientific and Industrial Research, Institute of Microbial Technology, Sector 39A, Chandigarh, 160036, India
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Ravikanth Nanduri
- Department of Molecular Immunology, Council of Scientific and Industrial Research, Institute of Microbial Technology, Sector 39A, Chandigarh, 160036, India
- Center for Cancer Research, National Cancer Institute, Bethesda, MD, 20892, USA
| | - Shalini Gupta
- Department of Molecular Immunology, Council of Scientific and Industrial Research, Institute of Microbial Technology, Sector 39A, Chandigarh, 160036, India
| | - Asheesh Kumar Khare
- Department of Molecular Immunology, Council of Scientific and Industrial Research, Institute of Microbial Technology, Sector 39A, Chandigarh, 160036, India
| | - Ella Bhagyaraj
- Department of Molecular Immunology, Council of Scientific and Industrial Research, Institute of Microbial Technology, Sector 39A, Chandigarh, 160036, India
- Department of Infectious Disease and Immunology, University of Florida, Gainesville, FL, USA
| | - Rashmi Arora
- Department of Molecular Immunology, Council of Scientific and Industrial Research, Institute of Microbial Technology, Sector 39A, Chandigarh, 160036, India
| | - Pawan Gupta
- Department of Molecular Immunology, Council of Scientific and Industrial Research, Institute of Microbial Technology, Sector 39A, Chandigarh, 160036, India.
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11
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SUMOylation of PDPK1 Is required to maintain glycolysis-dependent CD4 T-cell homeostasis. Cell Death Dis 2022; 13:181. [PMID: 35210408 PMCID: PMC8873481 DOI: 10.1038/s41419-022-04622-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 01/26/2022] [Accepted: 02/07/2022] [Indexed: 11/08/2022]
Abstract
AbstractThe immune system is finely tuned to fight against infections, eradicate neoplasms, and prevent autoimmunity. Protein posttranslational modification (PTM) constitutes a molecular layer of regulation to guarantee the proper intensity of immune response. Herein, we report that UBC9-mediated protein SUMOylation plays an essential role in peripheral CD4 T-cell proliferation, but without a perceptible impact on T-cell polarization. Both conventional T-cell (Tcon) and regulatory T-cell (Treg) maintenance are differentially affected, which was likely caused by a shared deficit in cell glycolytic metabolism. Mechanistically, PDPK1 (3-phosphoinositide-dependent protein-kinase 1) was identified as a novel SUMOylation substrate, which occurred predominantly at lysine 299 (K299) located within the protein-kinase domain. Loss of PDPK1 SUMOylation impeded its autophosphorylation at serine 241 (S241), thereby leading to hypoactivation of downstream mTORC1 signaling coupled with incompetence of cell proliferation. Altogether, our results revealed a novel regulatory mechanism in peripheral CD4 T-cell homeostatic proliferation, which involves SUMOylation regulation of PDPK1–mTORC1 signaling-mediated glycolytic process.
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12
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PHLPP Signaling in Immune Cells. Curr Top Microbiol Immunol 2022; 436:117-143. [DOI: 10.1007/978-3-031-06566-8_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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13
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Amorim ST, Stafuzza NB, Kluska S, Peripolli E, Pereira ASC, Muller da Silveira LF, de Albuquerque LG, Baldi F. Genome-wide interaction study reveals epistatic interactions for beef lipid-related traits in Nellore cattle. Anim Genet 2021; 53:35-48. [PMID: 34407235 DOI: 10.1111/age.13124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/02/2021] [Indexed: 11/27/2022]
Abstract
Gene-gene interactions cause hidden genetic variation in natural populations and could be responsible for the lack of replication that is typically observed in complex traits studies. This study aimed to identify gene-gene interactions using the empirical Hilbert-Schmidt Independence Criterion method to test for epistasis in beef fatty acid profile traits of Nellore cattle. The dataset contained records from 963 bulls, genotyped using a 777 962k SNP chip. Meat samples of Longissimus muscle, were taken to measure fatty acid composition, which was quantified by gas chromatography. We chose to work with the sums of saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA), omega-3 (OM3), omega-6 (OM6), SFA:PUFA and OM3:OM6 fatty acid ratios. The SNPs in the interactions where P < 10 - 8 were mapped individually and used to search for candidate genes. Totals of 602, 3, 13, 23, 13, 215 and 169 candidate genes for SFAs, MUFAs, PUFAs, OM3s, OM6s and SFA:PUFA and OM3:OM6 ratios were identified respectively. The candidate genes found were associated with cholesterol, lipid regulation, low-density lipoprotein receptors, feed efficiency and inflammatory response. Enrichment analysis revealed 57 significant GO and 18 KEGG terms ( P < 0.05), most of them related to meat quality and complementary terms. Our results showed substantial genetic interactions associated with lipid profile, meat quality, carcass and feed efficiency traits for the first time in Nellore cattle. The knowledge of these SNP-SNP interactions could improve understanding of the genetic and physiological mechanisms that contribute to lipid-related traits and improve human health by the selection of healthier meat products.
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Affiliation(s)
- S T Amorim
- Departamento de Zootecnia, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista, Via de acesso Prof. Paulo Donato Castellane, s/no, Jaboticabal, CEP 14884-900, Brazil
| | - N B Stafuzza
- Instituto de Zootecnia - Centro de Pesquisa em Bovinos de Corte, Rodovia Carlos Tonanni, Km94, Sertãozinho, 14174-000, Brazil
| | - S Kluska
- Departamento de Zootecnia, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista, Via de acesso Prof. Paulo Donato Castellane, s/no, Jaboticabal, CEP 14884-900, Brazil
| | - E Peripolli
- Departamento de Zootecnia, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista, Via de acesso Prof. Paulo Donato Castellane, s/no, Jaboticabal, CEP 14884-900, Brazil
| | - A S C Pereira
- Faculdade de Zootecnia e Engenharia de Alimentos, Núcleo de Apoio à Pesquisa em Melhoramento Animal, Biotecnologia e Transgenia, Universidade de São Paulo, Rua Duque de Caxias Norte, 225, Pirassununga, CEP 13635-900, Brazil
| | - L F Muller da Silveira
- Faculdade de Zootecnia e Engenharia de Alimentos, Núcleo de Apoio à Pesquisa em Melhoramento Animal, Biotecnologia e Transgenia, Universidade de São Paulo, Rua Duque de Caxias Norte, 225, Pirassununga, CEP 13635-900, Brazil
| | - L G de Albuquerque
- Departamento de Zootecnia, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista, Via de acesso Prof. Paulo Donato Castellane, s/no, Jaboticabal, CEP 14884-900, Brazil
| | - F Baldi
- Departamento de Zootecnia, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista, Via de acesso Prof. Paulo Donato Castellane, s/no, Jaboticabal, CEP 14884-900, Brazil
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14
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Lupse B, Annamalai K, Ibrahim H, Kaur S, Geravandi S, Sarma B, Pal A, Awal S, Joshi A, Rafizadeh S, Madduri MK, Khazaei M, Liu H, Yuan T, He W, Gorrepati KDD, Azizi Z, Qi Q, Ye K, Oberholzer J, Maedler K, Ardestani A. Inhibition of PHLPP1/2 phosphatases rescues pancreatic β-cells in diabetes. Cell Rep 2021; 36:109490. [PMID: 34348155 PMCID: PMC8421018 DOI: 10.1016/j.celrep.2021.109490] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 06/06/2021] [Accepted: 07/14/2021] [Indexed: 12/16/2022] Open
Abstract
Pancreatic β-cell failure is the key pathogenic element of the complex metabolic deterioration in type 2 diabetes (T2D); its underlying pathomechanism is still elusive. Here, we identify pleckstrin homology domain leucine-rich repeat protein phosphatases 1 and 2 (PHLPP1/2) as phosphatases whose upregulation leads to β-cell failure in diabetes. PHLPP levels are highly elevated in metabolically stressed human and rodent diabetic β-cells. Sustained hyper-activation of mechanistic target of rapamycin complex 1 (mTORC1) is the primary mechanism of the PHLPP upregulation linking chronic metabolic stress to ultimate β-cell death. PHLPPs directly dephosphorylate and regulate activities of β-cell survival-dependent kinases AKT and MST1, constituting a regulatory triangle loop to control β-cell apoptosis. Genetic inhibition of PHLPPs markedly improves β-cell survival and function in experimental models of diabetes in vitro, in vivo, and in primary human T2D islets. Our study presents PHLPPs as targets for functional regenerative therapy of pancreatic β cells in diabetes.
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Affiliation(s)
- Blaz Lupse
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany
| | - Karthika Annamalai
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany
| | - Hazem Ibrahim
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany
| | - Supreet Kaur
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany
| | - Shirin Geravandi
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany
| | - Bhavishya Sarma
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany
| | - Anasua Pal
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany
| | - Sushil Awal
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany
| | - Arundhati Joshi
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany
| | - Sahar Rafizadeh
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany
| | - Murali Krishna Madduri
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany
| | - Mona Khazaei
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany
| | - Huan Liu
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany
| | - Ting Yuan
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany
| | - Wei He
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany
| | | | - Zahra Azizi
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany; Department of Molecular Medicine, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran 1449614535, Iran
| | - Qi Qi
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Keqiang Ye
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Jose Oberholzer
- Charles O. Strickler Transplant Center, University of Virginia Medical Center, Charlottesville, VA 22903, USA
| | - Kathrin Maedler
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany.
| | - Amin Ardestani
- Centre for Biomolecular Interactions Bremen, University of Bremen, 28359 Bremen, Germany; Department of Molecular Medicine, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran 1449614535, Iran.
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15
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Cai W, Zhang J, Zhou H, Li X, Lou F, Sun Y, Xu Z, Bai J, Yin Q, Wang Z, Sun L, Cai X, Tang S, Wu Y, Fan L, Wang H, Wang H, Li Q. Protein phosphatase 6 (Pp6) is crucial for regulatory T cell function and stability in autoimmunity. Genes Dis 2021; 9:562-575. [PMID: 35224167 PMCID: PMC8843994 DOI: 10.1016/j.gendis.2021.07.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 07/26/2021] [Accepted: 07/27/2021] [Indexed: 12/24/2022] Open
Abstract
Regulatory T (Treg) cells constitute a dynamic population that is critical in autoimmunity. Treg cell therapies for autoimmune diseases are mainly focused on enhancing their suppressive activities. However, recent studies demonstrated that certain inflammatory conditions induce Treg cell instability with diminished FoxP3 expression and convert them into pathogenic effector cells. Therefore, the identification of novel targets crucial to both Treg cell function and plasticity is of vital importance to the development of therapeutic approaches in autoimmunity. In this study, we found that conditional Pp6 knockout (cKO) in Treg cells led to spontaneous autoinflammation, immune cell activation, and diminished levels of FoxP3 in CD4+ T cells in mice. Loss of Pp6 in Treg cells exacerbated two classical mouse models of Treg-related autoinflammation. Mechanistically, Pp6 deficiency increased CpG motif methylation of the FoxP3 locus by dephosphorylating Dnmt1 and enhancing Akt phosphorylation at Ser473/Thr308, leading to impaired FoxP3 expression in Treg cells. In summary, our study proposes Pp6 as a critical positive regulator of FoxP3 that acts by decreasing DNA methylation of the FoxP3 gene enhancer and inhibiting Akt signaling, thus maintaining Treg cell stability and preventing autoimmune diseases.
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16
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The MAPK dual specific phosphatase (DUSP) proteins: A versatile wrestler in T cell functionality. Int Immunopharmacol 2021; 98:107906. [PMID: 34198238 DOI: 10.1016/j.intimp.2021.107906] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 06/02/2021] [Accepted: 06/18/2021] [Indexed: 12/25/2022]
Abstract
The functional state of T cells is diverse and under dynamic control for adapting to the changes of microenvironment. Reversible protein phosphorylation represents an important post-translational modification that not only involves in the immediate early response of T cells, but also affects their functionality in the long run. Perturbation of global phosphorylation profile and/or phosphorylation of specific signaling nodes result in aberrant T cell activity. Dual specific phosphatases (DUSPs), which target MAPKs and beyond, have increasingly been emerged as a versatile regulator in T cell biology. Herein in this mini review, we sought to summarize and discuss the impact of DUSP proteins on the regulation of effector T cell activity, T cell polarization, regulatory T cell development and T cell senescence/exhaustion. Given the distinctive engagement of each DUSP member under various disease settings such as chronic infection, autoimmune disorders, cancer and age-related diseases, DUSP proteins likely hold the promise to become a druggable target other than the existing therapeutics that are predominantly by manipulating protein kinase activity.
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17
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Werlen G, Jain R, Jacinto E. MTOR Signaling and Metabolism in Early T Cell Development. Genes (Basel) 2021; 12:genes12050728. [PMID: 34068092 PMCID: PMC8152735 DOI: 10.3390/genes12050728] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/10/2021] [Accepted: 05/10/2021] [Indexed: 12/12/2022] Open
Abstract
The mechanistic target of rapamycin (mTOR) controls cell fate and responses via its functions in regulating metabolism. Its role in controlling immunity was unraveled by early studies on the immunosuppressive properties of rapamycin. Recent studies have provided insights on how metabolic reprogramming and mTOR signaling impact peripheral T cell activation and fate. The contribution of mTOR and metabolism during early T-cell development in the thymus is also emerging and is the subject of this review. Two major T lineages with distinct immune functions and peripheral homing organs diverge during early thymic development; the αβ- and γδ-T cells, which are defined by their respective TCR subunits. Thymic T-regulatory cells, which have immunosuppressive functions, also develop in the thymus from positively selected αβ-T cells. Here, we review recent findings on how the two mTOR protein complexes, mTORC1 and mTORC2, and the signaling molecules involved in the mTOR pathway are involved in thymocyte differentiation. We discuss emerging views on how metabolic remodeling impacts early T cell development and how this can be mediated via mTOR signaling.
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18
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Weaver SR, Taylor EL, Zars EL, Arnold KM, Bradley EW, Westendorf JJ. Pleckstrin homology (PH) domain and Leucine Rich Repeat Phosphatase 1 (Phlpp1) Suppresses Parathyroid Hormone Receptor 1 (Pth1r) Expression and Signaling During Bone Growth. J Bone Miner Res 2021; 36:986-999. [PMID: 33434347 PMCID: PMC8131217 DOI: 10.1002/jbmr.4248] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 12/06/2020] [Accepted: 12/24/2020] [Indexed: 12/20/2022]
Abstract
Endochondral ossification is tightly controlled by a coordinated network of signaling cascades including parathyroid hormone (PTH). Pleckstrin homology (PH) domain and leucine rich repeat phosphatase 1 (Phlpp1) affects endochondral ossification by suppressing chondrocyte proliferation in the growth plate, longitudinal bone growth, and bone mineralization. As such, Phlpp1-/- mice have shorter long bones, thicker growth plates, and proportionally larger growth plate proliferative zones. The goal of this study was to determine how Phlpp1 deficiency affects PTH signaling during bone growth. Transcriptomic analysis revealed greater PTH receptor 1 (Pth1r) expression and enrichment of histone 3 lysine 27 acetylation (H3K27ac) at the Pth1r promoter in Phlpp1-deficient chondrocytes. PTH (1-34) enhanced and PTH (7-34) attenuated cell proliferation, cAMP signaling, cAMP response element-binding protein (CREB) phosphorylation, and cell metabolic activity in Phlpp1-inhibited chondrocytes. To understand the role of Pth1r action in the endochondral phenotypes of Phlpp1-deficient mice, Phlpp1-/- mice were injected with Pth1r ligand PTH (7-34) daily for the first 4 weeks of life. PTH (7-34) reversed the abnormal growth plate and long-bone growth phenotypes of Phlpp1-/- mice but did not rescue deficits in bone mineral density or trabecular number. These results show that elevated Pth1r expression and signaling contributes to increased proliferation in Phlpp1-/- chondrocytes and shorter bones in Phlpp1-deficient mice. Our data reveal a novel molecular relationship between Phlpp1 and Pth1r in chondrocytes during growth plate development and longitudinal bone growth. © 2021 American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
| | | | | | | | - Elizabeth W. Bradley
- Department of Orthopedic Surgery and Stem Cell Institute, University of Minnesota, Minneapolis, MN
| | - Jennifer J. Westendorf
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, USA
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19
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The PHLPP1 N-Terminal Extension Is a Mitotic Cdk1 Substrate and Controls an Interactome Switch. Mol Cell Biol 2021; 41:e0033320. [PMID: 33397691 PMCID: PMC8088274 DOI: 10.1128/mcb.00333-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
PH domain leucine-rich repeat protein phosphatase 1 (PHLPP1) is a tumor suppressor that directly dephosphorylates a wide array of substrates, most notably the prosurvival kinase Akt. However, little is known about the molecular mechanisms governing PHLPP1 itself. Here, we report that PHLPP1 is dynamically regulated in a cell cycle-dependent manner and deletion of PHLPP1 results in mitotic delays and increased rates of chromosomal segregation errors. We show that PHLPP1 is hyperphosphorylated during mitosis by Cdk1 in a functionally uncharacterized region known as the PHLPP1 N-terminal extension (NTE). A proximity-dependent biotin identification (BioID) interaction screen revealed that during mitosis, PHLPP1 dissociates from plasma membrane scaffolds, such as Scribble, by a mechanism that depends on its NTE and gains proximity to kinetochore and mitotic spindle proteins such as KNL1 and TPX2. Our data are consistent with a model in which phosphorylation of PHLPP1 during mitosis regulates binding to its mitotic partners and allows accurate progression through mitosis. The finding that PHLPP1 binds mitotic proteins in a cell cycle- and phosphorylation-dependent manner may have relevance to its tumor-suppressive function.
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20
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Lo Dico A, Martelli C, Diceglie C, Ottobrini L. The Multifaceted Role of CMA in Glioma: Enemy or Ally? Int J Mol Sci 2021; 22:2217. [PMID: 33672324 PMCID: PMC7926390 DOI: 10.3390/ijms22042217] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 02/18/2021] [Accepted: 02/20/2021] [Indexed: 12/14/2022] Open
Abstract
Chaperone-mediated autophagy (CMA) is a catabolic pathway fundamental for cell homeostasis, by which specific damaged or non-essential proteins are degraded. CMA activity has three main levels of regulation. The first regulatory level is based on the targetability of specific proteins possessing a KFERQ-like domain, which can be recognized by specific chaperones and delivered to the lysosomes. Target protein unfolding and translocation into the lysosomal lumen constitutes the second level of CMA regulation and is based on the modulation of Lamp2A multimerization. Finally, the activity of some accessory proteins represents the third regulatory level of CMA activity. CMA's role in oncology has not been fully clarified covering both pro-survival and pro-death roles in different contexts. Taking all this into account, it is possible to comprehend the actual complexity of both CMA regulation and the cellular consequences of its activity allowing it to be elected as a modulatory and not only catabolic machinery. In this review, the role covered by CMA in oncology is discussed with a focus on its relevance in glioma. Molecular correlates of CMA importance in glioma responsiveness to treatment are described to identify new early efficacy biomarkers and new therapeutic targets to overcome resistance.
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Affiliation(s)
- Alessia Lo Dico
- Department of Pathophysiology and Transplantation, University of Milan, Via F.Cervi 93, Segrate, 20090 Milan, Italy; (A.L.D.); (C.M.); (C.D.)
| | - Cristina Martelli
- Department of Pathophysiology and Transplantation, University of Milan, Via F.Cervi 93, Segrate, 20090 Milan, Italy; (A.L.D.); (C.M.); (C.D.)
| | - Cecilia Diceglie
- Department of Pathophysiology and Transplantation, University of Milan, Via F.Cervi 93, Segrate, 20090 Milan, Italy; (A.L.D.); (C.M.); (C.D.)
| | - Luisa Ottobrini
- Department of Pathophysiology and Transplantation, University of Milan, Via F.Cervi 93, Segrate, 20090 Milan, Italy; (A.L.D.); (C.M.); (C.D.)
- Institute of Molecular Bioimaging and Physiology, National Research Council (IBFM-CNR), Via F.Cervi 93, Segrate, 20090 Milan, Italy
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21
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Baffi TR, Cohen-Katsenelson K, Newton AC. PHLPPing the Script: Emerging Roles of PHLPP Phosphatases in Cell Signaling. Annu Rev Pharmacol Toxicol 2021; 61:723-743. [PMID: 32997603 PMCID: PMC11003498 DOI: 10.1146/annurev-pharmtox-031820-122108] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Whereas protein kinases have been successfully targeted for a variety of diseases, protein phosphatases remain an underutilized therapeutic target, in part because of incomplete characterization of their effects on signaling networks. The pleckstrin homology domain leucine-rich repeat protein phosphatase (PHLPP) is a relatively new player in the cell signaling field, and new roles in controlling the balance among cell survival, proliferation, and apoptosis are being increasingly identified. Originally characterized for its tumor-suppressive function in deactivating the prosurvival kinase Akt, PHLPP may have an opposing role in promoting survival, as recent evidence suggests. Additionally, identification of the transcription factor STAT1 as a substrate unveils a role for PHLPP as a critical mediator of transcriptional programs in cancer and the inflammatory response. This review summarizes the current knowledge of PHLPP as both a tumor suppressor and an oncogene and highlights emerging functions in regulating gene expression and the immune system. Understanding the context-dependent functions of PHLPP is essential for appropriate therapeutic intervention.
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Affiliation(s)
- Timothy R Baffi
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093-0721, USA;
| | - Ksenya Cohen-Katsenelson
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093-0721, USA;
| | - Alexandra C Newton
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093-0721, USA;
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22
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Stark AK, Davenport ECM, Patton DT, Scudamore CL, Vanhaesebroeck B, Veldhoen M, Garden OA, Okkenhaug K. Loss of Phosphatidylinositol 3-Kinase Activity in Regulatory T Cells Leads to Neuronal Inflammation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2020; 205:78-89. [PMID: 32414808 PMCID: PMC7311201 DOI: 10.4049/jimmunol.2000043] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 04/21/2020] [Indexed: 12/29/2022]
Abstract
Class I PI3K enzymes are critical for the maintenance of effective immunity. In T cells, PI3Kα and PI3Kδ are activated by the TCR and costimulatory receptors, whereas PI3Kγ is activated by G protein-coupled chemokine receptors. PI3Kδ is a key regulator of regulatory T (Treg) cell function. PI3K isoform-selective inhibitors are in development for the treatment of diseases associated with immune dysregulation, including chronic inflammatory conditions, cancer, and autoimmune diseases. Idelalisib (PI3Kδ), alpelisib (PI3Kα), duvelisib (PI3Kδ/γ), and copanlisib (pan-PI3K) have recently been approved for use in cancer treatment. Although effective, these therapies often have severe side effects associated with immune dysregulation and, in particular, loss of Treg cells. Therefore, it is important to gain a better understanding of the relative contribution of different PI3K isoforms under homeostatic and inflammatory conditions. Experimental autoimmune encephalitis is a mouse model of T cell-driven CNS inflammation, in which Treg cells play a key protective role. In this study, we show that PI3Kδ is required to maintain normal Treg cell development and phenotype under homeostatic conditions but that loss of PI3Kδ alone in Treg cells does not lead to autoimmunity. However, combined loss of PI3Kα and PI3Kδ signaling resulted in increased experimental autoimmune encephalitis disease severity. Moreover, mice lacking PI3Kα and PI3Kδ in Treg cells developed spontaneous peripheral nerve inflammation. These results show a key role for PI3K signaling in Treg cell-mediated protection against CNS inflammation.
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MESH Headings
- Animals
- Autoimmunity/genetics
- Class I Phosphatidylinositol 3-Kinases/genetics
- Class I Phosphatidylinositol 3-Kinases/metabolism
- Class Ib Phosphatidylinositol 3-Kinase/genetics
- Class Ib Phosphatidylinositol 3-Kinase/metabolism
- Encephalomyelitis, Autoimmune, Experimental/blood
- Encephalomyelitis, Autoimmune, Experimental/diagnosis
- Encephalomyelitis, Autoimmune, Experimental/immunology
- Encephalomyelitis, Autoimmune, Experimental/pathology
- Female
- Humans
- Male
- Mice
- Mice, Transgenic
- Myelin-Oligodendrocyte Glycoprotein/administration & dosage
- Myelin-Oligodendrocyte Glycoprotein/immunology
- Peptide Fragments/administration & dosage
- Peptide Fragments/immunology
- Peripheral Nerves/immunology
- Peripheral Nerves/pathology
- Severity of Illness Index
- Signal Transduction/genetics
- Signal Transduction/immunology
- T-Lymphocytes, Regulatory/immunology
- T-Lymphocytes, Regulatory/metabolism
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Affiliation(s)
- Anne-Katrien Stark
- Laboratory of Lymphocyte Signalling and Development, Babraham Research Campus, Cambridge CB22 3AT, United Kingdom
- Department of Pathology, University of Cambridge, Cambridge CB2 1QP, United Kingdom
| | - Elizabeth C M Davenport
- Laboratory of Lymphocyte Signalling and Development, Babraham Research Campus, Cambridge CB22 3AT, United Kingdom
- Royal Veterinary College, London NW1 0TU, United Kingdom
| | - Daniel T Patton
- Laboratory of Lymphocyte Signalling and Development, Babraham Research Campus, Cambridge CB22 3AT, United Kingdom
| | - Cheryl L Scudamore
- Royal Veterinary College, London NW1 0TU, United Kingdom
- Exepathology, Exmouth EX8 5LQ, United Kingdom
| | - Bart Vanhaesebroeck
- UCL Cancer Institute, University College London, London WC1E 6AG, United Kingdom
| | - Marc Veldhoen
- Laboratory of Lymphocyte Signalling and Development, Babraham Research Campus, Cambridge CB22 3AT, United Kingdom
- Instituto de Medicina Molecular, Joâo Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, 1649-028 Lisbon, Portugal; and
| | - Oliver A Garden
- Royal Veterinary College, London NW1 0TU, United Kingdom
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Klaus Okkenhaug
- Laboratory of Lymphocyte Signalling and Development, Babraham Research Campus, Cambridge CB22 3AT, United Kingdom;
- Department of Pathology, University of Cambridge, Cambridge CB2 1QP, United Kingdom
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23
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Modulation of regulatory T cell function and stability by co-inhibitory receptors. Nat Rev Immunol 2020; 20:680-693. [PMID: 32269380 DOI: 10.1038/s41577-020-0296-3] [Citation(s) in RCA: 121] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/11/2020] [Indexed: 12/12/2022]
Abstract
Regulatory T (Treg) cells constitute a dynamic population that is essential for controlling immune responses in health and disease. Defects in Treg cell function and decreases in Treg cell numbers have been observed in patients with autoimmunity and the opposite effects on Treg cells occur in cancer settings. Current research on new therapies for these diseases is focused on modulating Treg cell function to increase or decrease suppressive activity in autoimmunity and cancer, respectively. In this regard, several co-inhibitory receptors that are preferentially expressed by Treg cells under homeostatic conditions have recently been shown to control Treg cell function and stability in different disease settings. These receptors could be amenable to therapeutic targeting aimed at modulating Treg cell function and plasticity. This Review summarizes recent data regarding the role of co-inhibitory molecules in the control of Treg cell function and stability, with a focus on their roles and potential therapeutic use in autoimmunity and cancer.
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24
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Taylor H, Laurence ADJ, Uhlig HH. The Role of PTEN in Innate and Adaptive Immunity. Cold Spring Harb Perspect Med 2019; 9:cshperspect.a036996. [PMID: 31501268 DOI: 10.1101/cshperspect.a036996] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The lipid and protein phosphatase and tensin homolog (PTEN) controls the differentiation and activation of multiple immune cells. PTEN acts downstream from T- and B-cell receptors, costimulatory molecules, cytokine receptors, integrins, and also growth factor receptors. Loss of PTEN activity in human and mice is associated with cellular and humoral immune dysfunction, lymphoid hyperplasia, and autoimmunity. Although most patients with PTEN hamartoma tumor syndrome (PHTS) have no immunological symptoms, a subclinical immune dysfunction is present in many, and clinical immunodeficiency in few. Comparison of the immune phenotype caused by PTEN haploinsufficiency in PHTS, phosphoinositide 3-kinase (PI3K) gain-of-function in activated PI3K syndrome, and mice with conditional biallelic Pten deletion suggests a threshold model in which coordinated activity of several phosphatases control the PI3K signaling in a cell-type-specific manner. Emerging evidence highlights the role of PTEN in polygenic autoimmune disorders, infection, and the immunological response to cancer. Targeting the PI3K axis is an emerging therapeutic avenue.
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Affiliation(s)
- Henry Taylor
- Department of Surgery and Cancer, Imperial College London, London SW7 2AZ, United Kingdom
| | - Arian D J Laurence
- Translational Gastroenterology Unit, NIHR Oxford Biomedical Research Centre, Nuffield Department of Experimental Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, United Kingdom.,Department of Haematology, University College London Hospitals NHS Trust, London WC1E 6AG, United Kingdom
| | - Holm H Uhlig
- Translational Gastroenterology Unit, NIHR Oxford Biomedical Research Centre, Nuffield Department of Experimental Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, United Kingdom.,Department of Paediatrics, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, United Kingdom.,NIHR Oxford Biomedical Research Centre, Oxford OX3 9DU, United Kingdom
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25
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Functional reprogramming of regulatory T cells in the absence of Foxp3. Nat Immunol 2019; 20:1208-1219. [PMID: 31384057 PMCID: PMC6707855 DOI: 10.1038/s41590-019-0442-x] [Citation(s) in RCA: 101] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 06/06/2019] [Indexed: 01/25/2023]
Abstract
Regulatory T cells (Treg cells) deficient in the transcription factor Foxp3 lack suppressor function and manifest an effector T (Teff) cell-like phenotype. We demonstrate that Foxp3 deficiency dysregulates metabolic checkpoint kinase mammalian target of rapamycin (mTOR) complex 2 (mTORC2) signaling and gives rise to augmented aerobic glycolysis and oxidative phosphorylation. Specific deletion of the mTORC2 adaptor gene Rictor in Foxp3-deficient Treg cells ameliorated disease in a Foxo1 transcription factor-dependent manner. Rictor deficiency re-established a subset of Treg cell genetic circuits and suppressed the Teff cell-like glycolytic and respiratory programs, which contributed to immune dysregulation. Treatment of Treg cells from patients with FOXP3 deficiency with mTOR inhibitors similarly antagonized their Teff cell-like program and restored suppressive function. Thus, regulatory function can be re-established in Foxp3-deficient Treg cells by targeting their metabolic pathways, providing opportunities to restore tolerance in Treg cell disorders.
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26
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Cohen Katsenelson K, Stender JD, Kawashima AT, Lordén G, Uchiyama S, Nizet V, Glass CK, Newton AC. PHLPP1 counter-regulates STAT1-mediated inflammatory signaling. eLife 2019; 8:e48609. [PMID: 31408005 PMCID: PMC6692130 DOI: 10.7554/elife.48609] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 07/30/2019] [Indexed: 12/16/2022] Open
Abstract
Inflammation is an essential aspect of innate immunity but also contributes to diverse human diseases. Although much is known about the kinases that control inflammatory signaling, less is known about the opposing phosphatases. Here we report that deletion of the gene encoding PH domain Leucine-rich repeat Protein Phosphatase 1 (PHLPP1) protects mice from lethal lipopolysaccharide (LPS) challenge and live Escherichia coli infection. Investigation of PHLPP1 function in macrophages reveals that it controls the magnitude and duration of inflammatory signaling by dephosphorylating the transcription factor STAT1 on Ser727 to inhibit its activity, reduce its promoter residency, and reduce the expression of target genes involved in innate immunity and cytokine signaling. This previously undescribed function of PHLPP1 depends on a bipartite nuclear localization signal in its unique N-terminal extension. Our data support a model in which nuclear PHLPP1 dephosphorylates STAT1 to control the magnitude and duration of inflammatory signaling in macrophages.
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Affiliation(s)
| | - Joshua D Stender
- Department of Cellular and Molecular MedicineUniversity of California, San DiegoSan DiegoUnited States
| | - Agnieszka T Kawashima
- Department of PharmacologyUniversity of California, San DiegoSan DiegoUnited States
- Department of Pharmacology and Biomedical Sciences Graduate ProgramUniversity of California, San DiegoSan DiegoUnited States
| | - Gema Lordén
- Department of PharmacologyUniversity of California, San DiegoSan DiegoUnited States
| | - Satoshi Uchiyama
- Department of PediatricsUniversity of California, San DiegoSan DiegoUnited States
| | - Victor Nizet
- Department of PediatricsUniversity of California, San DiegoSan DiegoUnited States
- Skaggs School of Pharmacy and Pharmaceutical SciencesUniversity of California, San DiegoSan DiegoUnited States
| | - Christopher K Glass
- Department of Cellular and Molecular MedicineUniversity of California, San DiegoSan DiegoUnited States
| | - Alexandra C Newton
- Department of PharmacologyUniversity of California, San DiegoSan DiegoUnited States
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27
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Moreno Ayala MA, Li Z, DuPage M. Treg programming and therapeutic reprogramming in cancer. Immunology 2019; 157:198-209. [PMID: 30866047 DOI: 10.1111/imm.13058] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 01/16/2019] [Accepted: 01/22/2019] [Indexed: 12/17/2022] Open
Abstract
Overcoming the immunosuppressive tumour microenvironment is the major challenge impeding cancer immunotherapy today. Regulatory T-cells (Tregs) are prevalent in nearly all cancers and, as immunosuppressive regulators of immune responses, they are the principal opponents of cancer immunotherapy. However, disabling Tregs systemically causes severe autoimmune toxicity, hastening the need for more selective methods to target intratumoural Tregs. In this review, we discuss a burgeoning new modality to specifically target tumour-infiltrating Tregs (TI-Tregs) by reprogramming their functionality from immunosuppressive to immune stimulatory within tumours. As the basis for therapeutic selectivity of TI-Tregs, we will focus on the defining features of Tregs within cancer: their highly activated state controlled by the engagement of key surface receptors, their distinct metabolic programme, and their unique transcriptional programme. By identifying proteins and pathways that distinguish TI-Tregs from other Tregs in the body, as well as from the beneficial antitumour effector T-cells within tumours, we highlight mechanisms to selectively reprogramme TI-Tregs for the treatment of cancer.
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Affiliation(s)
- Mariela A Moreno Ayala
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA
| | - Zehui Li
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA
| | - Michel DuPage
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA
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28
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Nilchian A, Johansson J, Ghalali A, Asanin ST, Santiago A, Rosencrantz O, Sollerbrant K, Vincent CT, Sund M, Stenius U, Fuxe J. CXADR-Mediated Formation of an AKT Inhibitory Signalosome at Tight Junctions Controls Epithelial-Mesenchymal Plasticity in Breast Cancer. Cancer Res 2018; 79:47-60. [PMID: 30385615 DOI: 10.1158/0008-5472.can-18-1742] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 09/26/2018] [Accepted: 10/24/2018] [Indexed: 11/16/2022]
Abstract
Tight junctions (TJ) act as hubs for intracellular signaling pathways controlling epithelial cell fate and function. Deregulation of TJ is a hallmark of epithelial-mesenchymal transition (EMT), which contributes to carcinoma progression and metastasis. However, the signaling mechanisms linking TJ to the induction of EMT are not understood. Here, we identify a TJ-based signalosome, which controls AKT signaling and EMT in breast cancer. The coxsackie and adenovirus receptor (CXADR), a TJ protein with an essential yet uncharacterized role in organogenesis and tissue homeostasis, was identified as a key component of the signalosome. CXADR regulated the stability and function of the phosphatases and AKT inhibitors PTEN and PHLPP2. Loss of CXADR led to hyperactivation of AKT and sensitized cells to TGFβ1-induced EMT. Conversely, restoration of CXADR stabilized PHLPP2 and PTEN, inhibited AKT, and promoted epithelial differentiation. Loss of CXADR in luminal A breast cancer correlated with loss of PHLPP2 and PTEN and poor prognosis. These results show that CXADR promotes the formation of an AKT-inhibitory signalosome at TJ and regulates epithelial-mesenchymal plasticity in breast cancer cells. Moreover, loss of CXADR might be used as a prognostic marker in luminal breast cancer. SIGNIFICANCE: The tight junction protein CXADR controls epithelial-mesenchymal plasticity in breast cancer by stabilizing the AKT regulators PTEN and PHLPP2.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/79/1/47/F1.large.jpg.
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Affiliation(s)
- Azadeh Nilchian
- Department of Microbiology, Tumor and Cell biology (MTC), Karolinska Institutet, Stockholm, Sweden
| | - Joel Johansson
- Department of Microbiology, Tumor and Cell biology (MTC), Karolinska Institutet, Stockholm, Sweden
| | - Aram Ghalali
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Sandra T Asanin
- Department of Microbiology, Tumor and Cell biology (MTC), Karolinska Institutet, Stockholm, Sweden
| | - Ana Santiago
- Department of Microbiology, Tumor and Cell biology (MTC), Karolinska Institutet, Stockholm, Sweden
| | - Oskar Rosencrantz
- Department of Microbiology, Tumor and Cell biology (MTC), Karolinska Institutet, Stockholm, Sweden
| | - Kerstin Sollerbrant
- Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
| | - C Theresa Vincent
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.,Department of Physiology and Biophysics, Weill Cornell Medicine, New York, New York.,Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Malin Sund
- Department of Surgical and Perioperative Sciences, Umea University, Umea, Sweden
| | - Ulla Stenius
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Jonas Fuxe
- Department of Microbiology, Tumor and Cell biology (MTC), Karolinska Institutet, Stockholm, Sweden.
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29
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Jackson TC, Dixon CE, Janesko-Feldman K, Vagni V, Kotermanski SE, Jackson EK, Kochanek PM. Acute Physiology and Neurologic Outcomes after Brain Injury in SCOP/PHLPP1 KO Mice. Sci Rep 2018; 8:7158. [PMID: 29739983 PMCID: PMC5940799 DOI: 10.1038/s41598-018-25371-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 04/20/2018] [Indexed: 11/12/2022] Open
Abstract
Suprachiasmatic nucleus circadian oscillatory protein (SCOP) (a.k.a. PHLPP1) regulates long-term memory consolidation in the brain. Using a mouse model of controlled cortical impact (CCI) we tested if (1) brain tissue levels of SCOP/PHLPP1 increase after a traumatic brain injury (TBI), and (2) if SCOP/PHLPP1 gene knockout (KO) mice have improved (or worse) neurologic outcomes. Blood chemistry (pH, pCO2, pO2, pSO2, base excess, sodium bicarbonate, and osmolarity) and arterial pressure (MAP) differed in isoflurane anesthetized WT vs. KOs at baseline and up to 1 h post-injury. CCI injury increased cortical/hippocampal SCOP/PHLPP1 levels in WTs 7d and 14d post-injury. Injured KOs had higher brain tissue levels of phosphorylated AKT (pAKT) in cortex (14d post-injury), and higher levels of phosphorylated MEK (pMEK) in hippocampus (7d and 14d post-injury) and in cortex (7d post-injury). Consistent with an important role of SCOP/PHLPP1 on memory function, injured-KOs had near normal performance on the probe trial of the Morris water maze, whereas injured-WTs were impaired. CA1/CA3 hippocampal survival was lower in KOs vs. WTs 24 h post-injury but equivalent by 7d. No difference in 21d cortical lesion volume was detected. SCOP/PHLPP1 overexpression in cultured rat cortical neurons had no effect on 24 h cell death after a mechanical stretch-injury.
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Affiliation(s)
- Travis C Jackson
- University of Pittsburgh School of Medicine, Safar Center for Resuscitation Research, Children's Hospital of Pittsburgh of UPMC, John G. Rangos Research Center - 6th Floor 4401 Penn Avenue, Pittsburgh, PA, 15224, USA. .,University of Pittsburgh School of Medicine, Department of Critical Care Medicine, Scaife Hall, 3550 Terrace Street, Pittsburgh, USA.
| | - C Edward Dixon
- University of Pittsburgh School of Medicine, Safar Center for Resuscitation Research, Children's Hospital of Pittsburgh of UPMC, John G. Rangos Research Center - 6th Floor 4401 Penn Avenue, Pittsburgh, PA, 15224, USA.,University of Pittsburgh School of Medicine, Department of Neurology, 811 Kaufmann Medical Building, 3471 Fifth Avenue, Pittsburgh, USA
| | - Keri Janesko-Feldman
- University of Pittsburgh School of Medicine, Safar Center for Resuscitation Research, Children's Hospital of Pittsburgh of UPMC, John G. Rangos Research Center - 6th Floor 4401 Penn Avenue, Pittsburgh, PA, 15224, USA.,University of Pittsburgh School of Medicine, Department of Critical Care Medicine, Scaife Hall, 3550 Terrace Street, Pittsburgh, USA
| | - Vincent Vagni
- University of Pittsburgh School of Medicine, Safar Center for Resuscitation Research, Children's Hospital of Pittsburgh of UPMC, John G. Rangos Research Center - 6th Floor 4401 Penn Avenue, Pittsburgh, PA, 15224, USA.,University of Pittsburgh School of Medicine, Department of Critical Care Medicine, Scaife Hall, 3550 Terrace Street, Pittsburgh, USA
| | - Shawn E Kotermanski
- University of Pittsburgh School of Medicine, Department of Pharmacology and Chemical Biology, Bridgeside Point Building 1, 100 Technology Drive, Pittsburgh, USA
| | - Edwin K Jackson
- University of Pittsburgh School of Medicine, Department of Pharmacology and Chemical Biology, Bridgeside Point Building 1, 100 Technology Drive, Pittsburgh, USA
| | - Patrick M Kochanek
- University of Pittsburgh School of Medicine, Safar Center for Resuscitation Research, Children's Hospital of Pittsburgh of UPMC, John G. Rangos Research Center - 6th Floor 4401 Penn Avenue, Pittsburgh, PA, 15224, USA.,University of Pittsburgh School of Medicine, Department of Critical Care Medicine, Scaife Hall, 3550 Terrace Street, Pittsburgh, USA
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30
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Zhou W, Quan JH, Gao FF, Ismail HAHA, Lee YH, Cha GH. Modulated Gene Expression of Toxoplasma gondii Infected Retinal Pigment Epithelial Cell Line (ARPE-19) via PI3K/Akt or mTOR Signal Pathway. THE KOREAN JOURNAL OF PARASITOLOGY 2018; 56:135-145. [PMID: 29742868 PMCID: PMC5976016 DOI: 10.3347/kjp.2018.56.2.135] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 03/13/2018] [Accepted: 03/20/2018] [Indexed: 11/23/2022]
Abstract
Due to the critical location and physiological activities of the retinal pigment epithelial (RPE) cell, it is constantly subjected to contact with various infectious agents and inflammatory mediators. However, little is known about the signaling events in RPE involved in Toxoplasma gondii infection and development. The aim of the study is to screen the host mRNA transcriptional change of 3 inflammation-related gene categories, PI3K/Akt pathway regulatory components, blood vessel development factors and ROS regulators, to prove that PI3K/Akt or mTOR signaling pathway play an essential role in regulating the selected inflammation-related genes. The selected genes include PH domain and leucine- rich-repeat protein phosphatases (PHLPP), casein kinase2 (CK2), vascular endothelial growth factor (VEGF), pigment epithelium-derived factor (PEDF), glutamate-cysteine ligase (GCL), glutathione S-transferase (GST), and NAD(P)H: quinone oxidoreductase (NQO1). Using reverse transcription polymerase chain reaction (RT-PCR) and quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), we found that T. gondii up-regulates PHLPP2, CK2β, VEGF, GCL, GST, and NQO1 gene expression levels, but down-regulates PHLPP1 and PEDF mRNA transcription levels. PI3K inhibition and mTOR inhibition by specific inhibitors showed that most of these host gene expression patterns were due to activation of PI3K/Akt or mTOR pathways with some exceptional cases. Taken together, our results reveal a new molecular mechanism of these gene expression change dependent on PI3K/Akt or mTOR pathways and highlight more systematical insight of how an intracellular T. gondii can manipulate host genes to avoid host defense.
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Affiliation(s)
- Wei Zhou
- Institute of Immunology, Taishan Medical College, Tai'an 271-000, Shandong, China.,Department of Medical Science & Infection Biology, Chungnam National University, School of Medicine, Daejeon 34134, Korea
| | - Juan-Hua Quan
- Department of Gastroenterology, The Affiliated Hospital of Guangdong Medical University, Zhanjiang 524-001, Guangdong, China
| | - Fei-Fei Gao
- Department of Medical Science & Infection Biology, Chungnam National University, School of Medicine, Daejeon 34134, Korea
| | | | - Young-Ha Lee
- Department of Medical Science & Infection Biology, Chungnam National University, School of Medicine, Daejeon 34134, Korea
| | - Guang-Ho Cha
- Department of Medical Science & Infection Biology, Chungnam National University, School of Medicine, Daejeon 34134, Korea
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31
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Fan MY, Turka LA. Immunometabolism and PI(3)K Signaling As a Link between IL-2, Foxp3 Expression, and Suppressor Function in Regulatory T Cells. Front Immunol 2018; 9:69. [PMID: 29434595 PMCID: PMC5796885 DOI: 10.3389/fimmu.2018.00069] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2017] [Accepted: 01/10/2018] [Indexed: 01/05/2023] Open
Abstract
CD4+ Foxp3+ regulatory T cells (Tregs) are an essential component of immune homeostasis. Modulation of Treg function has been proposed as a means of treating autoimmune conditions and preventing rejection of organ transplants, although achieving this goal will require a detailed understanding of Treg signaling pathways. Signaling within Tregs is known to differ considerably from that observed in other T cell subsets. Of note, Tregs are the only cell type known to constitutively express CD25, the main ligand-binding subunit of the IL-2 receptor. The PI(3)K/Akt/mTOR cascade constitutes a major signaling pathway downstream of IL-2 and is closely tied to cellular metabolism. Due to increasing recognition of the links between cellular fuel usage and immune cell function, the interplay between IL-2 signaling and Treg metabolism represents an important space for exploration and a potential approach for immunomodulation. Here, we discuss how IL-2 may affect Treg metabolism via PI(3)K signaling, as well as the effects of altered metabolism on Treg lineage stability and suppressor function.
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Affiliation(s)
- Martin Y Fan
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Boston, MA, United States.,Program in Immunology, Division of Medical Sciences, Harvard Medical School, Boston, MA, United States
| | - Laurence A Turka
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Boston, MA, United States.,Program in Immunology, Division of Medical Sciences, Harvard Medical School, Boston, MA, United States
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32
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Pompura SL, Dominguez-Villar M. The PI3K/AKT signaling pathway in regulatory T-cell development, stability, and function. J Leukoc Biol 2018; 103:1065-1076. [PMID: 29357116 DOI: 10.1002/jlb.2mir0817-349r] [Citation(s) in RCA: 166] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 12/08/2017] [Accepted: 12/14/2017] [Indexed: 12/11/2022] Open
Abstract
The PI3K/AKT signaling pathway is an essential node in mammalian cells that controls cell growth, migration, proliferation, and metabolism. During the last decade, a number of works have demonstrated an important role for the PI3K/AKT pathway in regulatory T cell development, function, and stability. This review summarizes our current knowledge of how the PI3K/AKT pathway regulates thymic and peripheral Treg generation and function, with an emphasis on translation of these observations to therapies targeting Tregs in several pathologies.
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Affiliation(s)
- Saige L Pompura
- Department of Immunobiology, Yale School of Medicine, New Haven, Connecticut, USA
- Department of Neurology, Human and Translational Immunology Program, Yale School of Medicine, New Haven, Connecticut, USA
| | - Margarita Dominguez-Villar
- Department of Neurology, Human and Translational Immunology Program, Yale School of Medicine, New Haven, Connecticut, USA
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33
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The Secrets of T Cell Polarization. Oncoimmunology 2018. [DOI: 10.1007/978-3-319-62431-0_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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34
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Alamuru-Yellapragada NP, Vundyala S, Behera S, Parsa KVL. LPS depletes PHLPP levels in macrophages through the inhibition of SP1 dependent transcriptional regulation. Biochem Biophys Res Commun 2017; 486:533-538. [PMID: 28322791 DOI: 10.1016/j.bbrc.2017.03.080] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 03/17/2017] [Indexed: 11/18/2022]
Abstract
We have previously reported that bacterial endotoxin LPS attenuates expression of PHLPP, a ser/thr phosphatase, at both transcript and protein levels in different immune cells, however the underlying molecular mechanism is unknown and is of significant interest. Here, in line with the decreased transcript levels upon LPS treatment, we observed that LPS caused significant reduction in PHLPP promoter activity. We observed that SP1, a transcription factor frequently associated with inflammation, was recruited to the PHLPP promoter region. Ectopic expression of SP1 enhanced both transcript and protein levels of PHLPP while knockdown of SP1 or pharmacological inhibition of SP1 DNA binding by mithramycin reduced PHLPP expression. Moreover, over-expression of SP1 co-activators CBP/p300 augmented SP1 driven PHLPP promoter activity. Of note, LPS treatment depleted SP1 and CBP protein levels due to which recruitment of SP1 to PHLPP promoter was reduced. Further, we found that re-introduction of SP1 restored promoter activity and transcript levels of PHLPP in LPS stimulated cells. Collectively, our data revealed the molecular mechanism underlying the regulation of PHLPP expression during LPS induced macrophage inflammatory response.
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Affiliation(s)
- Neeraja P Alamuru-Yellapragada
- Department of Biology, Dr. Reddy's Institute of Life Sciences, University of Hyderabad Campus, Hyderabad, Telangana, India
| | - Sanghamitra Vundyala
- Department of Biology, Dr. Reddy's Institute of Life Sciences, University of Hyderabad Campus, Hyderabad, Telangana, India
| | - Soma Behera
- Department of Biology, Dr. Reddy's Institute of Life Sciences, University of Hyderabad Campus, Hyderabad, Telangana, India
| | - Kishore V L Parsa
- Department of Biology, Dr. Reddy's Institute of Life Sciences, University of Hyderabad Campus, Hyderabad, Telangana, India.
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35
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Iwasaki K, Yamamoto T, Inanaga Y, Hiramitsu T, Miwa Y, Murotani K, Narumi S, Watarai Y, Katayama A, Uchida K, Kobayashi T. MiR-142-5p and miR-486-5p as biomarkers for early detection of chronic antibody-mediated rejection in kidney transplantation. Biomarkers 2016; 22:45-54. [PMID: 27323802 DOI: 10.1080/1354750x.2016.1204000] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
De novo donor-specific HLA antibody (DSA) would not necessarily contribute to chronic antibody-mediated rejection (CAMR) in kidney transplantation. Here, we investigated whether PBMC miRNAs could be predictable biomarkers for CAMR. Microarray profiling of 435 mature miRNAs in pooled samples was conducted. Individual analysis revealed that miR-142-5p was significantly (p < 0.01) underexpressed in patients with DSA. After DSA production, miR-486-5p and its target PTEN/foxO3 mRNA were significantly overexpressed (p < 0.01) and underexpressed (p < 0.01), respectively, in patients with biopsy-proven CAMR, compared with non-CAMR. Our studies suggest that miRNA expression patterns may serve as noninvasive diagnostic biomarkers to evaluate immune response and kidney allograft status.
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Affiliation(s)
- Kenta Iwasaki
- a Department of Kidney Disease and Transplant Immunology , Aichi Medical University , Nagakute , Japan
| | - Takayuki Yamamoto
- b Department of Transplant Surgery , Nagoya Daini Red Cross Hospital , Nagoya , Japan
| | - Yukiko Inanaga
- c Department of Surgery II , Nagoya University School of Medicine , Nagoya , Japan
| | - Takahisa Hiramitsu
- b Department of Transplant Surgery , Nagoya Daini Red Cross Hospital , Nagoya , Japan
| | - Yuko Miwa
- c Department of Surgery II , Nagoya University School of Medicine , Nagoya , Japan
| | - Kenta Murotani
- d Department of Center for Clinical Research , Aichi Medical University , Nagakute , Japan
| | - Shuji Narumi
- b Department of Transplant Surgery , Nagoya Daini Red Cross Hospital , Nagoya , Japan
| | - Yoshihiko Watarai
- b Department of Transplant Surgery , Nagoya Daini Red Cross Hospital , Nagoya , Japan
| | - Akio Katayama
- e Department of Transplant Surgery , Masuko Memorial Hospital , Nagoya , Japan
| | - Kazuharu Uchida
- a Department of Kidney Disease and Transplant Immunology , Aichi Medical University , Nagakute , Japan.,f Department of Transplant Surgery , Aichi Medical University , Nagakute , Japan
| | - Takaaki Kobayashi
- f Department of Transplant Surgery , Aichi Medical University , Nagakute , Japan
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Immune dysregulation in patients with PTEN hamartoma tumor syndrome: Analysis of FOXP3 regulatory T cells. J Allergy Clin Immunol 2016; 139:607-620.e15. [PMID: 27477328 PMCID: PMC5292998 DOI: 10.1016/j.jaci.2016.03.059] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 01/25/2016] [Accepted: 03/22/2016] [Indexed: 12/14/2022]
Abstract
Background Patients with heterozygous germline mutations in phosphatase and tensin homolog deleted on chromosome 10 (PTEN) experience autoimmunity and lymphoid hyperplasia. Objectives Because regulation of the phosphoinositide 3-kinase (PI3K) pathway is critical for maintaining regulatory T (Treg) cell functions, we investigate Treg cells in patients with heterozygous germline PTEN mutations (PTEN hamartoma tumor syndrome [PHTS]). Methods Patients with PHTS were assessed for immunologic conditions, lymphocyte subsets, forkhead box P3 (FOXP3)+ Treg cell levels, and phenotype. To determine the functional importance of phosphatases that control the PI3K pathway, we assessed Treg cell induction in vitro, mitochondrial depolarization, and recruitment of PTEN to the immunologic synapse. Results Autoimmunity and peripheral lymphoid hyperplasia were found in 43% of 79 patients with PHTS. Immune dysregulation in patients with PHTS included lymphopenia, CD4+ T-cell reduction, and changes in T- and B-cell subsets. Although total CD4+FOXP3+ Treg cell numbers are reduced, frequencies are maintained in the blood and intestine. Despite pathogenic PTEN mutations, the FOXP3+ T cells are phenotypically normal. We show that the phosphatase PH domain leucine-rich repeat protein phosphatase (PHLPP) downstream of PTEN is highly expressed in normal human Treg cells and provides complementary phosphatase activity. PHLPP is indispensable for the differentiation of induced Treg cells in vitro and Treg cell mitochondrial fitness. PTEN and PHLPP form a phosphatase network that is polarized at the immunologic synapse. Conclusion Heterozygous loss of function of PTEN in human subjects has a significant effect on T- and B-cell immunity. Assembly of the PTEN-PHLPP phosphatase network allows coordinated phosphatase activities at the site of T-cell receptor activation, which is important for limiting PI3K hyperactivation in Treg cells despite PTEN haploinsufficiency.
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Harnessing the plasticity of CD4(+) T cells to treat immune-mediated disease. Nat Rev Immunol 2016; 16:149-63. [PMID: 26875830 DOI: 10.1038/nri.2015.18] [Citation(s) in RCA: 353] [Impact Index Per Article: 44.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
CD4(+) T cells differentiate and acquire distinct functions to combat specific pathogens but can also adapt their functions in response to changing circumstances. Although this phenotypic plasticity can be potentially deleterious, driving immune pathology, it also provides important benefits that have led to its evolutionary preservation. Here, we review CD4(+) T cell plasticity by examining the molecular mechanisms that regulate it - from the extracellular cues that initiate and drive cells towards varying phenotypes, to the cytosolic signalling cascades that decipher these cues and transmit them into the cell and to the nucleus, where these signals imprint specific gene expression programmes. By understanding how this functional flexibility is achieved, we may open doors to new therapeutic approaches that harness this property of T cells.
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Chen M, Nowak DG, Trotman LC. Molecular pathways: PI3K pathway phosphatases as biomarkers for cancer prognosis and therapy. Clin Cancer Res 2015; 20:3057-63. [PMID: 24928944 DOI: 10.1158/1078-0432.ccr-12-3680] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cancer research has seen tremendous changes over the past decade. Fast progress in sequencing technology has afforded us with landmark genetic alterations, which had immediate impact on clinical science and practice by pointing to new kinase targets, such as phosphoinositide 3-kinase (PI3K), the EGF receptor, or BRAF. The PI3K pathway for growth control has emerged as a prime example for both oncogene activation and tumor suppressor loss in cancer. Here, we discuss how therapy using PI3K pathway inhibitors could benefit from information on specific phosphatases, which naturally antagonize the kinase targets. This PI3K pathway is found mutated in most cancer types, including prostate, breast, colon, and brain tumors. The tumor-suppressing phosphatases operate at two levels. Lipid-level phosphatases, such as PTEN and INPP4B, revert PI3K activity to keep the lipid second messengers inactive. At the protein level, PHLPP1/2 protein phosphatases inactivate AKT kinase, thus antagonizing mTOR complex 2 activity. However, in contrast with their kinase counterparts the phosphatases are unlikely drug targets. They would need to be stimulated by therapy and are commonly deleted and mutated in cancer. Yet, because they occupy critical nodes in preventing cancer initiation and progression, the information on their status has tremendous potential in outcome prediction, and in matching the available kinase inhibitor repertoire with the right patients. Clin Cancer Res; 20(12); 3057-63. ©2014 AACR.
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Affiliation(s)
- Muhan Chen
- Authors' Affiliation: Cold Spring Harbor Laboratory, Cold Spring Harbor, New York
| | - Dawid G Nowak
- Authors' Affiliation: Cold Spring Harbor Laboratory, Cold Spring Harbor, New York
| | - Lloyd C Trotman
- Authors' Affiliation: Cold Spring Harbor Laboratory, Cold Spring Harbor, New York
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39
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Huynh A, DuPage M, Priyadharshini B, Sage PT, Quiros J, Borges CM, Townamchai N, Gerriets VA, Rathmell JC, Sharpe AH, Bluestone JA, Turka LA. Control of PI(3) kinase in Treg cells maintains homeostasis and lineage stability. Nat Immunol 2015; 16:188-96. [PMID: 25559257 PMCID: PMC4297515 DOI: 10.1038/ni.3077] [Citation(s) in RCA: 323] [Impact Index Per Article: 35.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 12/01/2014] [Indexed: 12/13/2022]
Abstract
Foxp3(+) regulatory T cells (Treg cells) are required for immunological homeostasis. One notable distinction between conventional T cells (Tconv cells) and Treg cells is differences in the activity of phosphatidylinositol-3-OH kinase (PI(3)K); only Tconv cells downregulate PTEN, the main negative regulator of PI(3)K, upon activation. Here we found that control of PI(3)K in Treg cells was essential for lineage homeostasis and stability. Mice lacking Pten in Treg cells developed an autoimmune-lymphoproliferative disease characterized by excessive T helper type 1 (TH1) responses and B cell activation. Diminished control of PI(3)K activity in Treg cells led to reduced expression of the interleukin-2 (IL-2) receptor α subunit CD25, accumulation of Foxp3(+)CD25(-) cells and, ultimately, loss of expression of the transcription factor Foxp3 in these cells. Collectively, our data demonstrate that control of PI(3)K signaling by PTEN in Treg cells is critical for maintaining their homeostasis, function and stability.
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Affiliation(s)
- Alexandria Huynh
- Division of Medical Sciences, Harvard Medical School, Boston, MA
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Boston, MA
| | - Michel DuPage
- Diabetes Center and the Department of Medicine, University of California - San Francisco, San Francisco, CA
| | - Bhavana Priyadharshini
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Boston, MA
| | - Peter T. Sage
- Division of Immunology, Department of Microbiology, Harvard Medical School, Boston, MA
| | - Jason Quiros
- Diabetes Center and the Department of Medicine, University of California - San Francisco, San Francisco, CA
| | - Christopher M. Borges
- Division of Medical Sciences, Harvard Medical School, Boston, MA
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Boston, MA
| | - Natavudh Townamchai
- Division of Nephrology, Department of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Valerie A. Gerriets
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC
| | - Jeffrey C. Rathmell
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC
| | - Arlene H. Sharpe
- Division of Immunology, Department of Microbiology, Harvard Medical School, Boston, MA
| | - Jeffrey A. Bluestone
- Diabetes Center and the Department of Medicine, University of California - San Francisco, San Francisco, CA
| | - Laurence A. Turka
- Division of Medical Sciences, Harvard Medical School, Boston, MA
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Boston, MA
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Basu S, Hubbard B, Shevach EM. Foxp3-mediated inhibition of Akt inhibits Glut1 (glucose transporter 1) expression in human T regulatory cells. J Leukoc Biol 2014; 97:279-83. [PMID: 25492937 DOI: 10.1189/jlb.2ab0514-273rr] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
CD4(+)CD25(+)Foxp3(+) Tregs have a diminished capacity to activate the PI3K/Akt pathway. Although blunted Akt activity is necessary to maintain Treg function, the consequences of this altered signaling are unclear. Glut1 is a cell-surface receptor responsible for facilitating glucose transport across plasma membranes, whose expression is tightly coupled to costimulatory signals and Akt phosphorylation. Freshly isolated human Tregs were unable to up-regulate Glut1 in response to TCR and costimulatory signals compared with Tconv. Consequently, the ability of Tregs to use glucose was also reduced. Introduction of Foxp3 into Tconv inhibited Akt activation and Glut1 expression, indicating that Foxp3 can regulate Glut1. Finally, pharmacologic activation of Akt in Tregs can induce Glut1, overcoming the effects of Foxp3. Together, these results illustrate the molecular basis behind differential glucose metabolism in Tregs.
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Affiliation(s)
- Samik Basu
- Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Britany Hubbard
- Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Ethan M Shevach
- Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
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41
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Abstract
Precise control of the balance between protein phosphorylation, catalyzed by protein kinases, and protein dephosphorylation, catalyzed by protein phosphatases, is essential for cellular homeostasis. Dysregulation of this balance leads to pathophysiological states, driving diseases such as cancer, heart disease, and diabetes. Aberrant phosphorylation of components of the pathways that control cell growth and cell survival are particularly prevalent in cancer. One of the most studied tumor suppressors in these pathways is the lipid phosphatase PTEN (phosphatase and tensin homolog deleted on chromosome ten), which dephosphorylates the lipid second messenger phosphatidylinositol 3,4,5-trisphosphate (PIP3), thus preventing activation of the oncogenic kinase AKT (v-akt murine thymoma viral oncogene homolog). In 2005, the discovery of a family of protein phosphatases whose members directly dephosphorylate and inactivate AKT introduced a new negative regulator of the phosphoinositide 3-kinase (PI3K) oncogenic pathway. Pleckstrin homology domain leucine-rich repeat protein phosphatase (PHLPP) isozymes comprise a novel tumor suppressor family whose two members, PHLPP1 and PHLPP2, are deleted as frequently as PTEN in cancers such as those of the prostate. PHLPP is thus a novel therapeutic target to suppress oncogenic pathways and is a potential candidate biomarker to stratify patients for the appropriate targeted therapeutics. This review discusses the role of PHLPP in terminating AKT signaling and how pharmacological intervention would impact this pathway.
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Affiliation(s)
- Alexandra C Newton
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093;
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42
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Wells AD, Morawski PA. New roles for cyclin-dependent kinases in T cell biology: linking cell division and differentiation. Nat Rev Immunol 2014; 14:261-70. [PMID: 24603166 PMCID: PMC10114933 DOI: 10.1038/nri3625] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The proliferation of a few antigen-reactive lymphocytes into a large population of effector cells is a fundamental property of adaptive immunity. The cell division that fuels this process is driven by signals from antigen, co-stimulatory molecules and growth factor receptors, and is controlled by the cyclin-dependent kinase (CDK) cascade. In this Opinion article, we discuss how the CDK cascade provides one potential link between cell division and differentiation through the phosphorylation of immunologically relevant transcription factors, and how components of this pathway might ultimately participate in the decision between tolerance and immunity.
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Affiliation(s)
- Andrew D Wells
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, USA; and The Children's Hospital of Philadelphia Research Institute, Abramson Research Center, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Peter A Morawski
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, USA; and The Children's Hospital of Philadelphia Research Institute, Abramson Research Center, 3615 Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA
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43
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Alamuru NP, Behera S, Butchar JP, Tridandapani S, Kaimal Suraj S, Babu PP, Hasnain SE, Ehtesham NZ, Parsa KVL. A novel immunomodulatory function of PHLPP1: inhibition of iNOS via attenuation of STAT1 ser727 phosphorylation in mouse macrophages. J Leukoc Biol 2014; 95:775-783. [PMID: 24443556 DOI: 10.1189/jlb.0713360] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 12/10/2013] [Accepted: 01/06/2014] [Indexed: 11/24/2022] Open
Abstract
PHLPP1 is a novel tumor suppressor, but its role in the regulation of innate immune responses, which are frequently dysregulated in cancer, is unexplored. Here, we report that LPS attenuated PHLPP1 expression at mRNA and protein levels in immune cells, suggesting its involvement in immune responses. To test this, we overexpressed PHLPP1 in RAW 264.7 macrophages and observed a dramatic reduction in LPS/IFN-γ-induced iNOS expression. Conversely, silencing of PHLPP1 by siRNA or by shRNA robustly augmented LPS/IFN-γ-induced iNOS expression. qPCR and iNOS promoter reporter experiments showed that PHLPP1 inhibited iNOS transcription. Mechanistic analysis revealed that PHLPP1 suppressed LPS/IFN-γ-induced phosphorylation of ser727 STAT1; however, the underlying mechanisms differed. PHLPP1 reduced IFN-γ-stimulated but not LPS-induced ERK1/2 phosphorylation, and inhibition of ERK1/2 abolished IFN-γ-induced ser727 STAT1 phosphorylation and iNOS expression. In contrast, PHLPP1 knockdown augmented LPS-induced but not IFN-γ-elicited p38 phosphorylation. Blockade of p38 abolished LPS-stimulated phosphorylation of ser727 STAT1 and iNOS expression. Furthermore, PHLPP1 suppressed LPS-induced phosphorylation of tyr701 STAT1 by dampening p38-dependent IFN-β feedback. Collectively, our data demonstrate for the first time that PHLPP1 plays a vital role in restricting innate immune responses of macrophages, and further studies may show it to be a potential therapeutic target within the context of dysregulated macrophage activity.
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Affiliation(s)
| | - Soma Behera
- Dr. Reddy's Institute of Life Sciences (DRILS), Hyderabad, India
| | | | | | | | - P Prakash Babu
- Department of Internal Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Seyed E Hasnain
- Department of Biological Sciences, Indian Institute of Technology, New Delhi, India; and
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44
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Piccioni M, Chen Z, Tsun A, Li B. Regulatory T-cell differentiation and their function in immune regulation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 841:67-97. [PMID: 25261205 DOI: 10.1007/978-94-017-9487-9_4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Regulatory T-cells (Treg) represent a subset of CD4+ T-cells characterized by high suppressive capacity, which can be generated in the thymus or induced in the periphery. The deleterious phenotype of the Scurfy mouse, which develops an X-linked lymphoproliferative disease resulting from defective T-cell tolerance, clearly demonstrates the importance of Treg cells for the maintenance of immune homeostasis. Although significant progress has been achieved, much information regarding the development, characteristics and function of Treg cells remain lacking. This chapter highlights the most recent discoveries in the field of Treg biology, focusing on the development and role of this cell subset in the maintenance of immune balance.
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Affiliation(s)
- Miranda Piccioni
- Key Laboratory of Molecular Virology and Immunology, Unit of Molecular Immunology, Institute Pasteur of Shanghai, Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200025, China
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45
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Han JM, Patterson SJ, Speck M, Ehses JA, Levings MK. Insulin inhibits IL-10-mediated regulatory T cell function: implications for obesity. THE JOURNAL OF IMMUNOLOGY 2013; 192:623-9. [PMID: 24323581 DOI: 10.4049/jimmunol.1302181] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Chronic inflammation is known to promote metabolic dysregulation in obesity and type 2 diabetes. Although the precise origin of the unchecked inflammatory response in obesity is unclear, it is known that overproduction of proinflammatory cytokines by innate immune cells affects metabolism. For example, TNF-α contributes to the inability of cells to respond to insulin and to the increase in levels of insulin. Whether this hyperinsulinemia itself is part of a feedback loop that affects the progression of chronic adipose inflammation is unknown. In this article, we show that regulatory T cells (Tregs) express the insulin receptor, and that high levels of insulin impair the ability of Tregs to suppress inflammatory responses via effects on the AKT/mTOR signaling pathway. Insulin activated AKT signaling in Tregs, leading to inhibition of both IL-10 production and the ability of Tregs to suppress the production of TNF-α by macrophages in a contact-independent manner. The effect of insulin on Treg suppression was limited to IL-10 production and it did not alter the expression of other proteins associated with Treg function, including CTLA-4, CD39, and TGF-β. In a model of diet-induced obesity, Tregs from the visceral adipose tissue of hyperinsulinemic, obese mice showed a similar specific decrease in IL-10 production, as well as a parallel increase in production of IFN-γ. These data suggest that hyperinsulinemia may contribute to the development of obesity-associated inflammation via a previously unknown effect of insulin on the IL-10-mediated function of Tregs.
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Affiliation(s)
- Jonathan M Han
- Department of Surgery, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
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46
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Dong L, Jin L, Tseng HY, Wang CY, Wilmott JS, Yosufi B, Yan XG, Jiang CC, Scolyer RA, Zhang XD, Guo ST. Oncogenic suppression of PHLPP1 in human melanoma. Oncogene 2013; 33:4756-66. [PMID: 24121273 DOI: 10.1038/onc.2013.420] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 08/30/2013] [Accepted: 09/02/2013] [Indexed: 12/12/2022]
Abstract
Akt is constitutively activated in up to 70% of human melanomas and has an important role in the pathogenesis of the disease. However, little is known about protein phosphatases that dephosphorylate and thereby inactivate it in melanoma cells. Here we report that suppression of pleckstrin homology domain and leucine-rich repeat Ser/Thr protein phosphatase 1 (PHLPP1) by DNA methylation promotes Akt activation and has an oncogenic role in melanoma. While it is commonly downregulated, overexpression of PHLPP1 reduces Akt activation and inhibits melanoma cell proliferation in vitro, and retards melanoma growth in a xenograft model. In contrast, knockdown of PHLPP1 increases Akt activation, enhances melanoma cell and melanocyte proliferation, and results in anchorage-independent growth of melanocytes. Suppression of PHLPP1 involves blockade of binding of the transcription factor Sp1 to the PHLPP1 promoter. Collectively, these results suggest that suppression of PHLPP1 by DNA methylation contributes to melanoma development and progression.
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Affiliation(s)
- L Dong
- School of Medicine and Public Health, The University of Newcastle, Newcastle, NSW, Australia
| | - L Jin
- School of Medicine and Public Health, The University of Newcastle, Newcastle, NSW, Australia
| | - H-Y Tseng
- School of Medicine and Public Health, The University of Newcastle, Newcastle, NSW, Australia
| | - C Y Wang
- Department of Molecular Biology, Shanxi Cancer Hospital and Institute, Affiliated Hospital of Shanxi Medical University, Taiyuan, China
| | - J S Wilmott
- 1] Melanoma Institute Australia, Sydney, NSW, Australia [2] Discipline of Pathology, The University of Sydney, Sydney, NSW, Australia
| | - B Yosufi
- Melanoma Institute Australia, Sydney, NSW, Australia
| | - X G Yan
- School of Medicine and Public Health, The University of Newcastle, Newcastle, NSW, Australia
| | - C C Jiang
- School of Medicine and Public Health, The University of Newcastle, Newcastle, NSW, Australia
| | - R A Scolyer
- 1] Melanoma Institute Australia, Sydney, NSW, Australia [2] Discipline of Pathology, The University of Sydney, Sydney, NSW, Australia [3] Tissue Pathology and Diagnostic Oncology, Royal Prince Alfred Hospital, Sydney, NSW, Australia
| | - X D Zhang
- School of Medicine and Public Health, The University of Newcastle, Newcastle, NSW, Australia
| | - S T Guo
- Department of Molecular Biology, Shanxi Cancer Hospital and Institute, Affiliated Hospital of Shanxi Medical University, Taiyuan, China
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47
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Vent-Schmidt J, Han JM, MacDonald KG, Levings MK. The Role of FOXP3 in Regulating Immune Responses. Int Rev Immunol 2013; 33:110-28. [DOI: 10.3109/08830185.2013.811657] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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48
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Abstract
The interplay of the immune system with other aspects of physiology is continually being revealed and in some cases studied in considerable mechanistic detail. A prime example is the influence of metabolic cues on immune responses. It is well appreciated that upon activation, T cells take on a metabolic profile profoundly distinct from that of their quiescent and anergic counterparts; however, a number of recent breakthroughs have greatly expanded our knowledge of how aspects of cellular metabolism can shape a T-cell response. Particularly important are findings that certain environmental cues can tilt the delicate balance between inflammation and immune tolerance by skewing T-cell fate decisions toward either the T-helper 17 (Th17) or T-regulatory (Treg) cell lineage. Recognizing the unappreciated immune-modifying potential of metabolic factors and particularly those involved in the generation of these functionally opposing T-cell subsets will likely add new and potent therapies to our repertoire for treating immune mediated pathologies. In this review, we summarize and discuss recent findings linking certain metabolic pathways, enzymes, and by-products to shifts in the balance between Th17 and Treg cell populations. These advances highlight numerous opportunities for immune modulation.
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Affiliation(s)
- Joseph Barbi
- Department of Oncology, Immunology and Hematopoiesis Division, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Etemire E, Krull M, Hasenberg M, Reichardt P, Gunzer M. Transiently reduced PI3K/Akt activity drives the development of regulatory function in antigen-stimulated Naïve T-cells. PLoS One 2013; 8:e68378. [PMID: 23874604 PMCID: PMC3708928 DOI: 10.1371/journal.pone.0068378] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Accepted: 05/27/2013] [Indexed: 12/22/2022] Open
Abstract
Regulatory T-cells (Tregs) are central for immune homeostasis and divided in thymus-derived natural Tregs and peripherally induced iTreg. However, while phenotype and function of iTregs are well known, a remarkable lack exists in knowledge about signaling mechanisms leading to their generation from naïve precursors in peripheral tissues. Using antigen specific naïve T-cells from mice, we investigated CD4+ CD25+ FoxP3- iTreg induction during antigen-specific T-cell receptor (TCR) stimulation with weak antigen presenting cells (APC). We show that early signaling pathways such as ADAM-17-activation appeared similar in developing iTreg and effector cells (Teff) and both initially shedded CD62-L. But iTreg started reexpressing CD62-L after 24 h while Teff permanently downmodulated it. Furthermore, between 24 and 72 hours iTreg presented with significantly lower phosphorylation levels of Akt-S473 suggesting lower activity of the PI3K/Akt-axis. This was associated with a higher expression of the Akt hydrophobic motif-specific phosphatase PHLPP1 in iTreg. Importantly, the lack of costimulatory signals via CD28 from weak APC was central for the development of regulatory function in iTreg but not for the reappearance of CD62-L. Thus, T-cells display a window of sensitivity after onset of TCR triggering within which the intensity of the PI3K/Akt signal controls entry into either effector or regulatory pathways.
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MESH Headings
- ADAM Proteins/genetics
- ADAM Proteins/immunology
- ADAM Proteins/metabolism
- ADAM17 Protein
- Animals
- Antigen-Presenting Cells/immunology
- Antigen-Presenting Cells/metabolism
- Down-Regulation
- L-Selectin/genetics
- L-Selectin/immunology
- L-Selectin/metabolism
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Phosphatidylinositol 3-Kinases/genetics
- Phosphatidylinositol 3-Kinases/immunology
- Phosphatidylinositol 3-Kinases/metabolism
- Phosphorylation
- Proto-Oncogene Proteins c-akt/genetics
- Proto-Oncogene Proteins c-akt/immunology
- Proto-Oncogene Proteins c-akt/metabolism
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/immunology
- Receptors, Antigen, T-Cell/metabolism
- Signal Transduction
- T-Lymphocytes, Regulatory/immunology
- T-Lymphocytes, Regulatory/metabolism
- TOR Serine-Threonine Kinases/genetics
- TOR Serine-Threonine Kinases/immunology
- TOR Serine-Threonine Kinases/metabolism
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Affiliation(s)
- Eloho Etemire
- University Duisburg-Essen, University Hospital, Institute for Experimental Immunology and Imaging, Essen, Germany
| | - Marco Krull
- Otto von Guericke University, Institute of Molecular and Clinical Immunology, Magdeburg, Germany
| | - Mike Hasenberg
- University Duisburg-Essen, University Hospital, Institute for Experimental Immunology and Imaging, Essen, Germany
| | - Peter Reichardt
- Otto von Guericke University, Institute of Molecular and Clinical Immunology, Magdeburg, Germany
- * E-mail: (MG); (PR)
| | - Matthias Gunzer
- University Duisburg-Essen, University Hospital, Institute for Experimental Immunology and Imaging, Essen, Germany
- * E-mail: (MG); (PR)
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50
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Reid-Adam J, Yang N, Song Y, Cravedi P, Li XM, Heeger P. Immunosuppressive effects of the traditional Chinese herb Qu Mai on human alloreactive T cells. Am J Transplant 2013; 13:1159-67. [PMID: 23433080 PMCID: PMC3640757 DOI: 10.1111/ajt.12180] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Revised: 01/02/2013] [Accepted: 01/03/2013] [Indexed: 01/25/2023]
Abstract
Current therapies for transplant rejection are suboptimally effective. In an effort to discover novel immunosuppressants we used cytokine ELISPOT and ELISAs to screen extracts from 53 traditional Chinese herbs for their ability to suppress human alloreactive T cells. We identified a dichloromethane-soluble fraction (Qu Mai fraction AD [QMAD]) of Qu Mai (Dianthus superbus) as a candidate. High-performance liquid chromatography (HPLC) analysis of QMAD revealed three dominant peaks, each with a MW ~600 Daltons and distinct from cyclosporine and rapamycin. When we added QMAD to human mixed lymphocyte cultures, we observed dose-dependent inhibition of proliferation and IFNγ production, by naïve and memory alloreactive T cells, and observed an increased frequency of Foxp3(+) CD4(+) T cells. To address whether QMAD induces regulatory T cells we added QMAD to anti-CD3/CD28-stimulated naïve CD4 T cells and observed a dose-dependent upregulation of Foxp3 associated with new suppressive capacity. Mechanistically, QMAD did not induce T cell IL-10 or TGFβ but blocked T cell AKT phosphorylation, a key signaling nexus required for T cell proliferation and expansion, that simultaneously prevents Foxp3 transcription. Our findings provide novel insight into the antiinflammatory effects of one traditional Chinese herb, and support the need for continued isolation, characterization and testing of QMAD-derived components as immune suppressants for transplant rejection.
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Affiliation(s)
- Jessica Reid-Adam
- Division of Pediatric Nephrology, Mount Sinai School of Medicine, NY, NY, 10029
| | - Nan Yang
- Division of Pediatric Allergy and Immunology, Mount Sinai School of Medicine, NY, NY, 10029
| | - Ying Song
- Division of Pediatric Allergy and Immunology, Mount Sinai School of Medicine, NY, NY, 10029
| | - Paolo Cravedi
- Division of Nephrology, Mount Sinai School of Medicine, NY, NY, 10029
| | - Xiu-Min Li
- Division of Pediatric Allergy and Immunology, Mount Sinai School of Medicine, NY, NY, 10029
| | - Peter Heeger
- Division of Nephrology, Mount Sinai School of Medicine, NY, NY, 10029
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