title: RNAi-mediated TCR knockdown prevents autoimmunity in mice caused by mixed TCR dimers following TCR gene transfer.
abstract: Genetically modified T cells that express a transduced T cell receptor (TCR) α/β heterodimer in addition to their endogenous TCR are used in clinical studies to treat cancer. These cells express two TCR-α and two TCR-β chains that do not only compete for CD3 proteins but also form potentially self-reactive mixed TCR dimers, composed of endogenous and transferred chains. To overcome these deficits, we developed an RNAi-TCR replacement vector that simultaneously silences the endogenous TCR and expresses an RNAi-resistant TCR. Transduction of the virus-specific P14 TCR without RNAi resulted in unequal P14 TCR-α and -β chain surface levels, indicating heterodimerization with endogenous TCR chains. Such unequal expression was also observed following TCR gene optimization. Equal surface levels of the introduced TCR chains were however achieved by silencing the endogenous TCR. Importantly, all mice that received cells transduced with the native or optimized P14 TCR developed lethal TCR gene transfer-induced graft-versus-host-disease (TI-GVHD) due to formation of mixed TCR dimers. In contrast, TI-GVHD was almost completely prevented when using the RNAi-TCR replacement vector. Our data demonstrate that RNAi-assisted TCR replacement reduces the formation of mixed TCR dimers, and thereby significantly reduces the risk of TI-GVHD in TCR gene therapy.
authors.affiliation: 1] Max Delbrück Center for Molecular Medicine, Berlin, Germany [2] Institute of Biology, Humboldt-Universität zu Berlin, Berlin, Germany.
authors.forename: Mario
authors.initials: M
authors.lastname: Bunse
authors.affiliation: 1] Division of Immunology, The Netherlands Cancer Institute, Amsterdam, The Netherlands [2] Current address: School of Cancer Sciences, University of Birmingham, Birmingham, UK.
authors.forename: Gavin M
authors.initials: GM
authors.lastname: Bendle
authors.affiliation: Division of Immunology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
authors.forename: Carsten
authors.initials: C
authors.lastname: Linnemann
authors.affiliation: Division of Immunology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
authors.forename: Laura
authors.initials: L
authors.lastname: Bies
authors.affiliation: Institute of Pathology, Charité Campus Mitte, Berlin, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Schulz
authors.affiliation: Division of Immunology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
authors.forename: Ton N
authors.initials: TN
authors.lastname: Schumacher
authors.affiliation: 1] Max Delbrück Center for Molecular Medicine, Berlin, Germany [2] Institute of Biology, Humboldt-Universität zu Berlin, Berlin, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Uckert
mesh_terms: D000818:Animals; D015551:Autoimmunity; D002478:Cells, Cultured; D004195:Disease Models, Animal; D055785:Gene Knockdown Techniques; D005822:Genetic Vectors / Q000008:administration & dosage; D006086:Graft vs Host Disease / Q000517:prevention & control*; D008175:Lung Neoplasms / Q000276:immunology / Q000556:secondary* / Q000628:therapy*; D008546:Melanoma, Experimental / Q000276:immunology / Q000628:therapy*; D051379:Mice; D034622:RNA Interference; D011948:Receptors, Antigen, T-Cell / Q000037:antagonists & inhibitors* / Q000235:genetics; D013601:T-Lymphocytes / Q000276:immunology*; D014161:Transduction, Genetic
chemical_list: D011948:Receptors, Antigen, T-Cell