Antonelli Antonella, Sfara Carla, Rahmer Jürgen, Gleich Bernhard, Borgert Jörn, Magnani Mauro
Biomed Tech (Berl). 2013 Dec;58(6):517-25. doi: 10.1515/bmt-2012-0065.
Red blood cells (RBCs) represent intravascular carriers for drugs, biologics, and other therapeutic agents, characterized by their unique longevity in the bloodstream, availability, considerable surface and volume, high biocompatibility, and natural mechanisms for safe elimination. Recently, the potential of RBCs loaded with superparamagnetic iron oxide (SPIO) nanoparticles as a tracer material for magnetic particle imaging (MPI) to realize a blood-pool tracer agent with longer blood retention time for imaging of the circulatory system, has been investigated. MPI is a new tomographic imaging approach that can quantitatively map magnetic nanoparticle distributions in vivo. However, SPIO contrast agents, such as Resovist, have a short blood half-life due to rapid uptake by the reticuloendothelial system, which limits the applicability of such compounds for certain applications such as long-term monitoring. Here, we report the in vitro magnetic characterization study of human SPIO-loaded RBCs and the first MPI results obtained after intravenous injection of murine SPIO-loaded RBCs in an in vivo MPI experiment.
红细胞（RBCs）是药物、生物制品和其他治疗剂的血管内载体，其特点是在血液中具有独特的寿命、可用性、可观的表面积和体积、高生物相容性以及安全消除的天然机制。最近，研究了负载超顺磁性氧化铁（SPIO）纳米颗粒的红细胞作为磁粒子成像（MPI）示踪材料的潜力，以实现具有更长血液保留时间的血池示踪剂，用于循环系统成像。MPI是一种新的断层成像方法，可以在体内定量绘制磁性纳米颗粒的分布。然而，像Resovist这样的SPIO造影剂由于被网状内皮系统快速摄取，血液半衰期较短，这限制了此类化合物在某些应用（如长期监测）中的适用性。在此，我们报告了负载SPIO的人红细胞的体外磁性表征研究，以及在体内MPI实验中静脉注射负载SPIO的小鼠红细胞后获得的首个MPI结果。
