title: First inducible transgene expression in porcine large animal models.
abstract: The purpose of this study was to establish inducible transgene expression in pigs, a model organism with great promise for experimental physiology and translational medicine, using the binary tet-on system. This expression system is activated by doxycycline (dox) via the tet-controlled transactivator (TA). Binding of TA to the transactivator response element (TRE) results in transcription of downstream genes. First, we cloned transgenic founder pigs expressing TA under the control of the CMV enhancer/chicken β-actin promoter (CAG). Then, cells from CAG-TA transgenic founders were nucleofected with TRE-controlled expression vectors for either porcine cytotoxic T-lymphocyte associated antigen 4-Fc domain of immunoglobulin G1 (CTLA-4Ig) or soluble receptor activator of NF-κB ligand (RANKL), and double-transgenic offspring were cloned. Dox administration resulted in a dose-dependent increase in expression of CTLA-4Ig or RANKL, in nucleofected cells and in transgenic pigs, while in the absence of dox, the levels of both proteins were below the detection limit. Inducible transgene expression was reproduced in double-transgenic offspring generated by cloning or breeding. Our strategy revealed the first two examples of inducible transgene expression in pigs. The CAG-TA transgenic pigs generated in this study constitute an interesting basis for future pig models with inducible transgene expression.
authors.affiliation: Ludwig-Maximilians-Universitat Munchen, Munich, Germany.
authors.forename: Nikolai
authors.initials: N
authors.lastname: Klymiuk
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Böcker
authors.forename: Veronika
authors.initials: V
authors.lastname: Schönitzer
authors.forename: Andrea
authors.initials: A
authors.lastname: Bähr
authors.forename: Tamara
authors.initials: T
authors.lastname: Radic
authors.forename: Thomas
authors.initials: T
authors.lastname: Fröhlich
authors.forename: Annegret
authors.initials: A
authors.lastname: Wünsch
authors.forename: Barbara
authors.initials: B
authors.lastname: Keßler
authors.forename: Mayuko
authors.initials: M
authors.lastname: Kurome
authors.forename: Eleonore
authors.initials: E
authors.lastname: Schilling
authors.forename: Nadja
authors.initials: N
authors.lastname: Herbach
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Wanke
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nagashima
authors.forename: Wolf
authors.initials: W
authors.lastname: Mutschler
authors.forename: Georg J
authors.initials: GJ
authors.lastname: Arnold
authors.forename: Reinhard
authors.initials: R
authors.lastname: Schwinzer
authors.forename: Matthias
authors.initials: M
authors.lastname: Schieker
authors.forename: Eckhard
authors.initials: E
authors.lastname: Wolf
mesh_terms: D000069594:Abatacept; D000818:Animals; D030801:Animals, Genetically Modified / Q000235:genetics* / Q000378:metabolism; D000831:Animals, Newborn; D002478:Cells, Cultured; D002645:Chickens; D004305:Dose-Response Relationship, Drug; D004318:Doxycycline / Q000494:pharmacology*; D004624:Embryo Transfer / Q000379:methods; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects*; D018796:Immunoconjugates / Q000235:genetics / Q000378:metabolism; D007668:Kidney / Q000166:cytology / Q000378:metabolism; D008297:Male; D023421:Models, Animal; D009865:Oocytes / Q000166:cytology / Q000378:metabolism; D061251:Primary Cell Culture; D053245:RANK Ligand / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013552:Swine; D014162:Transfection; D019076:Transgenes / Q000235:genetics*
chemical_list: D018796:Immunoconjugates; D053245:RANK Ligand; D000069594:Abatacept; D004318:Doxycycline