In Vivo Mesenchymal Stem Cell Tracking with PET Using the Dopamine Type 2 Receptor and 18F-Fallypride

Journal of Nuclear Medicine

Stefanie Käsbauer¹  Veronika Schönitzer¹  Wolfgang Böcker¹  Florian Haasters¹  Andreas Delker¹  Guido Böning¹  Roswitha Beck¹  Matthias Schieker¹  Manuela Pape¹  Franz Josef Gildehaus¹  Peter Bartenstein¹  Veronika Ulrich¹  Erik Mille¹  Janette Carlsen¹  Wolf Mutschler¹ 

关键词: mesenchymal stem cells;    in vivo imaging;    cell tracking;    dopamine 2 receptor;    positron emission tomography;   

DOI  :  10.2967/jnumed.113.134775

学科分类：医学（综合）

来源: Society of Nuclear Medicine

【 摘 要 】

Human mesenchymal stem cells (hMSCs) represent a promising treatment approach for tissue repair and regeneration. However, little is known about the underlying mechanisms and the fate of the transplanted cells. The objective of the presented work was to determine the feasibility of PET imaging and in vivo monitoring after transplantation of dopamine type 2 receptor–expressing cells. Methods: An hMSC line constitutively expressing a mutant of the dopamine type 2 receptor (D2R80A) was generated by lentiviral gene transfer. D2R80A messenger RNA expression was confirmed by reverse transcriptase-polymerase chain reaction. Localization of the transmembrane protein was analyzed by confocal fluorescence microscopy. The stem cell character of transduced hMSCs was investigated by adipogenic and osteogenic differentiation. Migration capacity was assessed by scratch assays in time-lapse imaging. In vitro specific binding of ligands was tested by fluorescence-activated cell sorting analysis and by radioligand assay using 18F-fallypride. Imaging of D2R80A overexpressing hMSC transplanted into athymic rats was performed by PET using 18F-fallypride. Results: hMSCs showed long-term overexpression of D2R80A. As expected, the fluorescence signal suggested the primary localization of the protein in the membrane of the transduced cells. hMSC and D2R80A retained their stem cell character demonstrated by their osteogenic and adipogenic differentiation capacity and their proliferation and migration behavior. For in vitro hMSCs, at least 90% expressed the D2R80A transgene and hMSC-D2R80A showed specific binding of 18F-fallypride. In vivo, a specific signal was detected at the transplantation site up to 7 d by PET. Conclusion: The mutant of the dopamine type 2 receptor (D2R80A) is a potent reporter to detect hMSCs by PET in vivo.

【 授权许可】

Unknown