Zhang Hua, Wang Zhen-Jun, Wang Ling-Jie, Li Ting-Ting, He Sheng, Li Li-Ping, Li Xiao-Yan, Liu Shi-Jie, Li Jian-Ding, Li Si-Jin, Zhang Rui-Ping
Department of Medical Imaging, First Hospital of Shanxi Medical University Taiyuan Shanxi Province 030001 China.
Department of Biochemistry and Molecular Biology, Shanxi Medical University Taiyuan Shanxi Province 030001 China.
RSC Adv. 2019 Oct 31;9(60):35003-35010. doi: 10.1039/c9ra05937g. eCollection 2019 Oct 28.
Stem cell imaging is critical to elucidate the homing, distribution, survival, and repair mechanisms and to evaluate the therapeutic effects of engrafted stem cells. Unfortunately, unimodal imaging of stem cells does not simultaneously satisfy all current requirements owing to their intrinsic limitations. Obviously, bimodal or multimodal imaging of stem cells is a promising strategy for circumventing this issue. This study aimed to design and synthesize a novel dual-modal polyethylene glycol-modified magnetic nanoparticle (Fe-PEG-MNP) based on natural biomaterials including melanin and Fe ions for photoacoustic (PA) and magnetic resonance (MR) imaging of stem cells . The Fe-PEG-MNPs were characterized and their PA/MR imaging capability and cytotoxicity were evaluated. Bone marrow mesenchymal stem cells (BM-MSCs) labeled with Fe-PEG-MNPs were subjected to PA and MR imaging and . Consequently, Fe-PEG-MNPs displayed many superior properties, including ultra-small particle size, higher stability, water solubility, easy labeling of cells, lower cytotoxicity, high biosafety, excellent capability of PA/MR imaging, high sensitivity and long-term monitoring and . In particular, PA and MR signals of labeled BM-MSCs were maintained for at least 35 and 28 d, respectively, . Therefore, Fe-PEG-MNPs are ideal dual-modal PA/MR nanoparticles for non-invasive and effective monitoring of engrafted stem cells .
干细胞成像对于阐明归巢、分布、存活及修复机制以及评估植入干细胞的治疗效果至关重要。不幸的是，由于其固有局限性，干细胞的单模态成像无法同时满足当前所有需求。显然，干细胞的双模态或多模态成像对于解决这一问题是一种很有前景的策略。本研究旨在基于包括黑色素和铁离子在内的天然生物材料设计并合成一种新型的用于干细胞光声（PA）和磁共振（MR）成像的双模态聚乙二醇修饰磁性纳米颗粒（Fe-PEG-MNP）。对Fe-PEG-MNP进行了表征，并评估了其PA/MR成像能力和细胞毒性。用Fe-PEG-MNP标记的骨髓间充质干细胞（BM-MSC）进行了PA和MR成像。结果，Fe-PEG-MNP表现出许多优异性能，包括超小粒径、更高的稳定性、水溶性、易于细胞标记、较低的细胞毒性、高生物安全性、出色的PA/MR成像能力、高灵敏度和长期监测能力。特别是，标记的BM-MSC的PA和MR信号分别至少维持了35天和28天。因此，Fe-PEG-MNP是用于无创和有效监测植入干细胞的理想双模态PA/MR纳米颗粒。
