title: Tracking of human cells in mice.
abstract: Tracking and tracing of transplanted cells in mice is required in many fields of research. Examples are transplantation of stem cells into organs of mice to study their differentiation capacity and injection of tumor cells to examine metastatic behavior. In the present study we tested the lipid dye CM-DiI and red fluorescent nanoparticles Qdot655 for their applicability in tagging and tracing of human cells in mice. Labeling of different cell types, including MCF-7 human breast cancer cells, human cord blood derived cells, human NeoHep cells and human hepatopancreatic precursor cells, is technically easy and did not compromise further cell culture. After transplantation of CM-DiI or Qdot655 marked cells, red fluorescent structures could be detected already in unprocessed paraffin slices of the studied organs, namely liver, lung, pancreas, kidney, spleen and bone marrow. Next, we examined whether the red fluorescent structures represent the transplanted human cells. For this purpose, we established an in situ hybridization (ISH) technique that allows clear-cut differentiation between human and murine nuclei, based on simultaneous hybridization with human alu and mouse major satellite (mms) probes. We observed a high degree of coincidence between CM-DiI-marked cells and alu positive nuclei. However, also some mms positive cells contained CM-DiI, suggesting phagocytosis of the transplanted CM-DiI-marked cells. The degree of such CM-DiI-positive mouse cells depended on the cell type and route of administration. From a technical point of view it was important that CM-DiI-positive structures in paraffin slices remained fluorescent also after ISH. In contrast, Qdot655 positive structures faded during further staining procedures. In conclusion, marking of cells with CM-DiI or Qdot655 prior to transplantation facilitates recovery of human cells, since a high fraction of positive structures in the host's tissue originate from the transplanted cells. However, CM-DiI or Qdot655 positive staining of individual cells in transplanted tissues is not sufficient to prove their human origin. Additional procedures, such as ISH with alu-probes, are essential, when characterizing individual cells.
authors.affiliation: Leibniz Research Centre for Working Environment and Human Factors at the University of Dortmund (IfADo), Ardeystrasse 67, 44139, Dortmund, Germany. schormann@ifado.de
authors.forename: Wiebke
authors.initials: W
authors.lastname: Schormann
authors.forename: Friedrich J
authors.initials: FJ
authors.lastname: Hammersen
authors.forename: Marc
authors.initials: M
authors.lastname: Brulport
authors.forename: Matthias
authors.initials: M
authors.lastname: Hermes
authors.forename: Alexander
authors.initials: A
authors.lastname: Bauer
authors.forename: Claudia
authors.initials: C
authors.lastname: Rudolph
authors.forename: Markus
authors.initials: M
authors.lastname: Schug
authors.forename: Thomas
authors.initials: T
authors.lastname: Lehmann
authors.forename: Andreas
authors.initials: A
authors.lastname: Nussler
authors.forename: Hendrik
authors.initials: H
authors.lastname: Ungefroren
authors.forename: James
authors.initials: J
authors.lastname: Hutchinson
authors.forename: Fred
authors.initials: F
authors.lastname: Fändrich
authors.forename: Jörg
authors.initials: J
authors.lastname: Petersen
authors.forename: Karsten
authors.initials: K
authors.lastname: Wursthorn
authors.forename: Martin R
authors.initials: MR
authors.lastname: Burda
authors.forename: Oliver
authors.initials: O
authors.lastname: Brüstle
authors.forename: Kannan
authors.initials: K
authors.lastname: Krishnamurthi
authors.forename: Marc
authors.initials: M
authors.lastname: von Mach
authors.forename: Jan G
authors.initials: JG
authors.lastname: Hengstler
mesh_terms: D000818:Animals; D002232:Carbocyanines / Q000737:chemistry* / Q000378:metabolism; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000737:chemistry / Q000648:ultrastructure; D036101:Cord Blood Stem Cell Transplantation; D005456:Fluorescent Dyes / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D008297:Male; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D008856:Microscopy, Fluorescence; D045663:Quantum Dots; D014183:Transplantation, Heterologous
chemical_list: C101089:CM-DiI; D002232:Carbocyanines; D005456:Fluorescent Dyes