title: The TGF-β-inducible miR-23a cluster attenuates IFN-γ levels and antigen-specific cytotoxicity in human CD8⁺ T cells.
abstract: Cytokine secretion and degranulation represent key components of CD8(+) T-cell cytotoxicity. While transcriptional blockade of IFN-γ and inhibition of degranulation by TGF-β are well established, we wondered whether TGF-β could also induce immune-regulatory miRNAs in human CD8(+) T cells. We used miRNA microarrays and high-throughput sequencing in combination with qRT-PCR and found that TGF-β promotes expression of the miR-23a cluster in human CD8(+) T cells. Likewise, TGF-β up-regulated expression of the cluster in CD8(+) T cells from wild-type mice, but not in cells from mice with tissue-specific expression of a dominant-negative TGF-β type II receptor. Reporter gene assays including site mutations confirmed that miR-23a specifically targets the 3'UTR of CD107a/LAMP1 mRNA, whereas the further miRNAs expressed in this cluster-namely, miR-27a and -24-target the 3'UTR of IFN-γ mRNA. Upon modulation of the miR-23a cluster by the respective miRNA antagomirs and mimics, we observed significant changes in IFN-γ expression, but only slight effects on CD107a/LAMP1 expression. Still, overexpression of the cluster attenuated the cytotoxic activity of antigen-specific CD8(+) T cells. These functional data thus reveal that the miR-23a cluster not only is induced by TGF-β, but also exerts a suppressive effect on CD8(+) T-cell effector functions, even in the absence of TGF-β signaling.
authors.affiliation: Graduate School of Life Sciences (GSLS), University of Würzburg, Germany; Department of Obstetrics and Gynecology.
authors.forename: P Anoop
authors.initials: PA
authors.lastname: Chandran
authors.affiliation: Chair for Clinical Bioinformatics, Saarland University, Saarbrücken, Germany;
authors.forename: Andreas
authors.initials: A
authors.lastname: Keller
authors.affiliation: Max Planck Institute of Biochemistry, Martinsried, Germany;
authors.forename: Lasse
authors.initials: L
authors.lastname: Weinmann
authors.affiliation: Department of Obstetrics and Gynecology, Interdisciplinary Center for Clinical Research.
authors.forename: Ahmed Adel
authors.initials: AA
authors.lastname: Seida
authors.affiliation: Pediatric Hematology, Oncology, and Stem Cell Transplantation, Children's Hospital.
authors.forename: Matthias
authors.initials: M
authors.lastname: Braun
authors.affiliation: Laboratory of Cellular and Molecular Lung Immunology, Institute of Molecular Pneumology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany; and.
authors.forename: Katerina
authors.initials: K
authors.lastname: Andreev
authors.affiliation: Department of Obstetrics and Gynecology.
authors.forename: Birgitt
authors.initials: B
authors.lastname: Fischer
authors.affiliation: Department of Obstetrics and Gynecology.
authors.forename: Evi
authors.initials: E
authors.lastname: Horn
authors.affiliation: Pediatric Hematology, Oncology, and Stem Cell Transplantation, Children's Hospital.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Schwinn
authors.affiliation: Department of Obstetrics and Gynecology, Interdisciplinary Center for Clinical Research.
authors.forename: Markus
authors.initials: M
authors.lastname: Junker
authors.affiliation: Department of Dermatology, University of Würzburg Medical School, Würzburg, Germany;
authors.forename: Roland
authors.initials: R
authors.lastname: Houben
authors.affiliation: Department of Obstetrics and Gynecology, Interdisciplinary Center for Clinical Research.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Dombrowski
authors.affiliation: Department of Obstetrics and Gynecology.
authors.forename: Johannes
authors.initials: J
authors.lastname: Dietl
authors.affiliation: Laboratory of Cellular and Molecular Lung Immunology, Institute of Molecular Pneumology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany; and.
authors.forename: Susetta
authors.initials: S
authors.lastname: Finotto
authors.affiliation: Pediatric Hematology, Oncology, and Stem Cell Transplantation, Children's Hospital.
authors.forename: Matthias
authors.initials: M
authors.lastname: Wölfl
authors.affiliation: Max Planck Institute of Biochemistry, Martinsried, Germany; Department of Biochemistry, University of Regensburg, Germany.
authors.forename: Gunter
authors.initials: G
authors.lastname: Meister
authors.affiliation: Department of Obstetrics and Gynecology, Interdisciplinary Center for Clinical Research, wischhusen_j@ukw.de.
authors.forename: Jörg
authors.initials: J
authors.lastname: Wischhusen
mesh_terms: D020413:3' Untranslated Regions; D001483:Base Sequence; D001665:Binding Sites; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism*; D002460:Cell Line; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007371:Interferon-gamma / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008213:Lymphocyte Activation / Q000235:genetics / Q000276:immunology; D052118:Lysosomal-Associated Membrane Protein 1 / Q000737:chemistry / Q000235:genetics; D058965:MART-1 Antigen / Q000276:immunology; D035683:MicroRNAs / Q000235:genetics*; D005810:Multigene Family; D034622:RNA Interference; D016212:Transforming Growth Factor beta / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D020413:3' Untranslated Regions; D018984:Epitopes, T-Lymphocyte; D052118:Lysosomal-Associated Membrane Protein 1; D058965:MART-1 Antigen; C552430:MIRN23a microRNA, human; C543845:MIRN24 microRNA, human; C531388:MIRN27 microRNA, human; D035683:MicroRNAs; D016212:Transforming Growth Factor beta; D007371:Interferon-gamma
keywords: antigen-specific T cells; miRNA induction; tolerance; tumor targets