title: Reporter gene-expressing bone marrow-derived stromal cells are immune-tolerated following implantation in the central nervous system of syngeneic immunocompetent mice.
abstract: BACKGROUND
  Cell transplantation is likely to become an important therapeutic tool for the treatment of various traumatic and ischemic injuries to the central nervous system (CNS). However, in many pre-clinical cell therapy studies, reporter gene-assisted imaging of cellular implants in the CNS and potential reporter gene and/or cell-based immunogenicity, still remain challenging research topics.
  
  
  RESULTS
  In this study, we performed cell implantation experiments in the CNS of immunocompetent mice using autologous (syngeneic) luciferase-expressing bone marrow-derived stromal cells (BMSC-Luc) cultured from ROSA26-L-S-L-Luciferase transgenic mice, and BMSC-Luc genetically modified using a lentivirus encoding the enhanced green fluorescence protein (eGFP) and the puromycin resistance gene (Pac) (BMSC-Luc/eGFP/Pac). Both reporter gene-modified BMSC populations displayed high engraftment capacity in the CNS of immunocompetent mice, despite potential immunogenicity of introduced reporter proteins, as demonstrated by real-time bioluminescence imaging (BLI) and histological analysis at different time-points post-implantation. In contrast, both BMSC-Luc and BMSC-Luc/eGFP/Pac did not survive upon intramuscular cell implantation, as demonstrated by real-time BLI at different time-points post-implantation. In addition, ELISPOT analysis demonstrated the induction of IFN-gamma-producing CD8+ T-cells upon intramuscular cell implantation, but not upon intracerebral cell implantation, indicating that BMSC-Luc and BMSC-Luc/eGFP/Pac are immune-tolerated in the CNS. However, in our experimental transplantation model, results also indicated that reporter gene-specific immune-reactive T-cell responses were not the main contributors to the immunological rejection of BMSC-Luc or BMSC-Luc/eGFP/Pac upon intramuscular cell implantation.
  
  
  CONCLUSIONS
  We here demonstrate that reporter gene-modified BMSC derived from ROSA26-L-S-L-Luciferase transgenic mice are immune-tolerated upon implantation in the CNS of syngeneic immunocompetent mice, providing a research model for studying survival and localisation of autologous BMSC implants in the CNS by real-time BLI and/or histological analysis in the absence of immunosuppressive therapy.
authors.affiliation: Laboratory of Experimental Hematology, University of Antwerp, Antwerp, Belgium. irene.bergwerf@ua.ac.be
authors.forename: Irene
authors.initials: I
authors.lastname: Bergwerf
authors.forename: Nathalie
authors.initials: N
authors.lastname: De Vocht
authors.forename: Bart
authors.initials: B
authors.lastname: Tambuyzer
authors.forename: Jacob
authors.initials: J
authors.lastname: Verschueren
authors.forename: Kristien
authors.initials: K
authors.lastname: Reekmans
authors.forename: Jasmijn
authors.initials: J
authors.lastname: Daans
authors.forename: Abdelilah
authors.initials: A
authors.lastname: Ibrahimi
authors.forename: Viggo
authors.initials: V
authors.lastname: Van Tendeloo
authors.forename: Shyama
authors.initials: S
authors.lastname: Chatterjee
authors.forename: Herman
authors.initials: H
authors.lastname: Goossens
authors.forename: Philippe G
authors.initials: PG
authors.lastname: Jorens
authors.forename: Veerle
authors.initials: V
authors.lastname: Baekelandt
authors.forename: Dirk
authors.initials: D
authors.lastname: Ysebaert
authors.forename: Eric
authors.initials: E
authors.lastname: Van Marck
authors.forename: Zwi N
authors.initials: ZN
authors.lastname: Berneman
authors.forename: Annemie Van Der
authors.initials: AV
authors.lastname: Linden
authors.forename: Peter
authors.initials: P
authors.lastname: Ponsaerts
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology*; D001921:Brain / Q000378:metabolism; D002478:Cells, Cultured; D003952:Diagnostic Imaging; D017930:Genes, Reporter; D008156:Luciferases / Q000235:genetics* / Q000378:metabolism; D049408:Luminescent Agents / Q000378:metabolism; D008163:Luminescent Measurements; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D023421:Models, Animal; D017154:Stromal Cells / Q000637:transplantation*; D023001:Transplantation Tolerance
chemical_list: D049408:Luminescent Agents; D008156:Luciferases