Park Serah, Kwak Byung Kook, Jung Jisung
Department of Radiology, Chung-Ang University College of Medicine, Seoul, Korea.
Department of Radiology, Chung-Ang University College of Medicine, Seoul, Korea ; Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Korea.
Iran J Radiol. 2015 Apr 22;12(2):e20782. doi: 10.5812/iranjradiol.20782. eCollection 2015 Apr.
Susceptibility-weighted imaging (SWI) is extremely sensitive in the detection of superparamagnetic iron oxide (SPIO) nanoparticle-labeled cells. However, no study has compared molecular imaging for stem cell detection using SWI and other MRI pulse sequences.
This study aims to assess the sensitivity of SWI in detecting SPIO nanoparticle-labeled, human bone marrow-derived mesenchymal stem cells (SPIO-hMSCs) compared with that of T2- and T2*-weighted imaging (T2WI and T2*WI, respectively) in a phantom and in vivo study in rats.
A phantom was prepared with various cell concentrations. In one normal rat, SPIO-hMSCs were implanted directly through burr holes into both caudate putamens, while in three rats without and six rats with photothrombotic infarction, 2.5 × 10(5)/ml SPIO-hMSCs were infused into the ipsilateral internal carotid artery (ICA). T2WI, T2*WI, and SWI findings were compared for dark regions representing SPIO-hMSCs.
SWI and T2WI detected 15 µL of 13 SPIO-hMSCs/µL and 15 µL of 27 SPIO-hMSCs/µL in the phantom, respectively and 3 µL of 333 SPIO-hMSCs/µL and 3 µL of 167 SPIO-hMSCs/µL in the normal rat brain (direct implantation). In the normal rat brain (ICA infusion), one of the three cases showed numerous foci of dark regions dispersed throughout the brain on T2WI and SWI. Dark regions surrounded the infarcts in all six infracted rat brains. The dark region was most prominent on SWI, followed by T2*WI and T2WI in all six rats (P = 0.002). Implanted SPIO-hMSCs were confirmed using Prussian blue staining.
SWI is the most sensitive in the detection of SPIO-hMSCs, with the dark regions representing SPIO-hMSCs being more prominent on SWI than on T2*WI and T2WI.
susceptibility加权成像（SWI）在检测超顺磁性氧化铁（SPIO）纳米颗粒标记的细胞方面极其敏感。然而，尚无研究比较使用SWI和其他MRI脉冲序列进行干细胞检测的分子成像。
本研究旨在评估在体模和大鼠体内研究中，与T2加权成像（T2WI）和T2加权成像（T2WI）相比，SWI检测SPIO纳米颗粒标记的人骨髓间充质干细胞（SPIO-hMSCs）的敏感性。
制备含有不同细胞浓度的体模。在一只正常大鼠中，通过钻孔将SPIO-hMSCs直接植入双侧尾状壳核，而在三只未发生光血栓性梗死和六只发生光血栓性梗死的大鼠中，将2.5×10⁵/ml的SPIO-hMSCs注入同侧颈内动脉（ICA）。比较T2WI、T2*WI和SWI上代表SPIO-hMSCs的暗区表现。
在体模中，SWI和T2WI分别检测到15μL的13个SPIO-hMSCs/μL和15μL的27个SPIO-hMSCs/μL，在正常大鼠脑（直接植入）中分别检测到3μL的333个SPIO-hMSCs/μL和3μL的167个SPIO-hMSCs/μL。在正常大鼠脑（ICA注入）中，三只大鼠中的一只在T2WI和SWI上显示脑内有许多暗区散在分布。在所有六只梗死大鼠脑中，暗区围绕梗死灶。在所有六只大鼠中，暗区在SWI上最明显，其次是T2*WI和T2WI（P = 0.002）。使用普鲁士蓝染色证实植入了SPIO-hMSCs。
SWI在检测SPIO-hMSCs方面最敏感，代表SPIO-hMSCs的暗区在SWI上比在T2*WI和T2WI上更明显。
