Department of Biomedical Engineering, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan.
J Biomater Appl. 2013 Sep;28(3):473-80. doi: 10.1177/0885328212462259. Epub 2012 Oct 9.
Magnetic resonance imaging is one of the most important fields for cellular imaging due to its non-invasive capacity, spatial resolution, and sensibility to visualized transplanted cells. An enhanced magnetic resonance image can be achieved by using contrast agents containing paramagnetic gadolinium chelates, which have the widest clinical use. To obtain a better contrast-enhancement and reduce the concentration of Gd for payload, one strategy is to conjugate the gadolinium(III) chelate to polymeric materials that will lead into an increase in the rotational correlation time and therefore improve the relaxivity. Four series of dextran gadolinium chelates were synthesized which are of interest as potential MRI contrast agents to track bone marrow-derived endothelial progenitor cells in vivo. The dextranes with molecular weights were characterized, introduced into the endothelial progenitor cells by electroporation, and injected in aqueous solution into rats to acquire the MR images. We have shown that by selecting polymers of the appropriate molecular weight, stability into the cell after labeling, relaxivity, and retention into the body can be accomplished.
磁共振成像是细胞成像中最重要的领域之一，因为它具有非侵入性、空间分辨率和对可视化移植细胞的敏感性。通过使用含有顺磁钆螯合物的对比剂可以获得增强的磁共振图像，顺磁钆螯合物具有最广泛的临床应用。为了获得更好的对比增强效果并降低载药量的 Gd 浓度，一种策略是将钆(III)螯合物与聚合物结合，这将导致旋转相关时间的增加，从而提高弛豫率。我们合成了四组葡聚糖钆螯合物，它们作为潜在的 MRI 对比剂，可用于追踪体内骨髓来源的内皮祖细胞。对具有不同分子量的葡聚糖进行了表征，通过电穿孔将其引入内皮祖细胞，并以水溶液形式注入大鼠体内以获取磁共振图像。我们已经表明，通过选择适当分子量的聚合物，可以实现标记后细胞内的稳定性、弛豫率和体内保留。
