Effective tracking of bone mesenchymal stem cells in vivo by magnetic resonance imaging using melanin-based gadolinium³⁺ nanoparticles

详细信息    查看全文

• 作者：Wen-Wen Cai ; Ling-Jie Wang ; Si-Jin Li ; Xi-Ping Zhang ; Ting-Ting- Li ; Ying-Hua Wang ; Xi Yang ; Jun Xie ; Jian-Ding Li ; Shi-Jie Liu ; Wen Xu ; Sheng He ; Zhen Cheng ; Qu-Li Fan and Rui-Ping Zhang
• 刊名：Journal of Biomedical Materials Research Part A
• 出版年：2017
• 出版时间：January 2017
• 年：2017
• 卷：105
• 期：1
• 页码：131-137
• 全文大小：552K
• ISSN：1552-4965

文摘

Tracking transplanted stem cells is necessary to clarify cellular properties and improve transplantation success. In this study, we designed and synthesized melanin-based gadolinium³⁺ (Gd³⁺)-chelate nanoparticles (MNP-Gd³⁺) of ∼7 nm for stem cell tracking in vivo. MNP-Gd³⁺ possesses many beneficial properties, such as its high stability and sensitivity, shorter T1 relaxation time, higher cell labeling efficiency, and lower cytotoxicity compared with commercial imaging agents. We found that the T1 relaxivity (r₁) of MNP-Gd³⁺ was significantly higher than that of Gd-DTPA; the nanoparticles were taken up by bone mesenchymal stem cells (BMSCs) via endocytosis and were broadly distributed in the cytoplasm. Based on an in vitro MTT assay, no cytotoxicity of labeled stem cells was observed for MNP-Gd³⁺ concentrations of less than 800 µg/mL. Furthermore, we tracked MNP-Gd³⁺-labeled BMSCs in vivo using 3.0T MRI equipment. After intramuscular injection, MNP-Gd³⁺-labeled BMSCs were detected, even after four weeks, by 3T MRI. We concluded that MNP-Gd³⁺ nanoparticles at appropriate concentrations can be used to effectively monitor and track BMSCs in vivo. MNP-Gd³⁺ nanoparticles have potential as a new positive MRI contrast agent in clinical applications.