title: Immunohistochemical toolkit for tracking and quantifying xenotransplanted human stem cells.
abstract: OBJECTIVE
  Biomarker-based tracking of human stem cells xenotransplanted into animal models is crucial for studying their fate in the field of cell therapy or tumor xenografting.
  
  
  METHODS
  Using immunohistochemistry and in situ hybridization, we analyzed the expression of three human-specific biomarkers: Ku80, human mitochondria (hMito) and Alu.
  
  
  RESULTS
  We showed that Ku80, hMito and Alu biomarkers are broadly expressed in human tissues with no or low cross-reactivity toward rat, mouse or pig tissues. In vitro, we demonstrated that their expression is stable over time and does not change along the differentiation of human-derived induced pluripotent stem cells or human glial-restricted precursors. We tracked in vivo these cell populations after transplantation in rodent spinal cords using aforementioned biomarkers and human-specific antibodies detecting apoptotic, proliferating or neural-committed cells.
  
  
  CONCLUSIONS
  This study assesses the human-species specificity of Ku80, hMito and Alu, and proposes useful biomarkers for characterizing human stem cells in xenotransplantation paradigms.
authors.affiliation: Department of Pathology, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium.
authors.forename: Justine
authors.initials: J
authors.lastname: Allard
authors.forename: Ké
authors.initials: K
authors.lastname: Li
authors.forename: Xavier Moles
authors.initials: XM
authors.lastname: Lopez
authors.forename: Stéphane
authors.initials: S
authors.lastname: Blanchard
authors.forename: Paul
authors.initials: P
authors.lastname: Barbot
authors.forename: Sandrine
authors.initials: S
authors.lastname: Rorive
authors.forename: Christine
authors.initials: C
authors.lastname: Decaestecker
authors.forename: Roland
authors.initials: R
authors.lastname: Pochet
authors.forename: Delphine
authors.initials: D
authors.lastname: Bohl
authors.forename: Angelo C
authors.initials: AC
authors.lastname: Lepore
authors.forename: Isabelle
authors.initials: I
authors.lastname: Salmon
authors.forename: Charles
authors.initials: C
authors.lastname: Nicaise
mesh_terms: D000818:Animals; D000943:Antigens, Differentiation / Q000378:metabolism*; D058948:Cell Tracking / Q000379:methods*; D064593:Heterografts; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D057026:Induced Pluripotent Stem Cells / Q000166:cytology / Q000378:metabolism / Q000637:transplantation; D008297:Male; D051379:Mice; D051381:Rats; D017207:Rats, Sprague-Dawley; D033581:Stem Cell Transplantation
chemical_list: D000943:Antigens, Differentiation
keywords: cell therapy; human-specific biomarker; image quantification; stem cells; xenotransplantation