Gadolinium3+-doped mesoporous silica nanoparticles as a potential magnetic resonance tracer for monitoring the migration of stem cells in vivo

Yingying Shen,1,2,* Yuanzhi Shao,3,* Haoqiang He,1 Yunpu Tan,4 Xiumei Tian,2 Fukang Xie,2 Li Li11Imaging Diagnostic and Interventional Center, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, China; 2Department of Histology and Embryology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China; 3Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-sen University, Guangzhou, Guangdong, China; 4Department of Gastrointestinal Surgery, Sun Yat-sen University, Guangzhou, Guangdong, China *These authors contributed equally to this workAbstract: We investigated the tracking potential of a magnetic resonance imaging (MRI) probe made of gadolinium-doped mesoporous silica MCM-41 (Gd2O3@MCM-41) nanoparticles for transplanted bone mesenchymal stem cells (MSCs) and neural stem cells (NSCs) in vivo. The nanoparticles, synthesized using a one-step synthetic method, possess hexagonal mesoporous structures with appropriate assembly of nanoscale Gd2O3 clusters. They show little cytotoxicity against proliferation and have a lower effect on the inherent differentiation potential of these labeled stem cells. The tracking of labeled NSCs in murine brains was dynamically determined with a clinical 3T MRI system for at least 14 days. The migration of labeled NSCs identified by MRI corresponded to the results of immunofluorescence imaging. Our study confirms that Gd2O3@MCM-41 particles can serve as an ideal vector for long-term MRI tracking of MSCs and NSCs in vivo.Keywords: nanoparticles, gadolinium, magnetic resonance imaging, stem cells