Huang Dong-Ming, Lu Chen-Wen, Hsiao Jong-Kai
Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Miaoli, Taiwan.
Department of Medical Imaging, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan.
Int J Nanomedicine. 2025 Aug 28;20:10469-10486. doi: 10.2147/IJN.S518933. eCollection 2025.
Mesenchymal stem cell (MSC) therapy shows promise in preclinical ischemic stroke models, yet clinical translation remains inconsistent. To address this gap, we investigated whether labeling MSCs with Ferucarbotran enables magnetic resonance imaging (MRI) tracking and enhances neural differentiation and functional integration, particularly focusing on the novel observation of spontaneous neuronal firing activity in transplanted cells.
Rat MSCs (rMSCs) were transduced with red fluorescent protein (RFP) and labeled with Ferucarbotran to generate Fer-RFP⁺ rMSCs. These were transplanted into rats subjected to middle cerebral artery occlusion. MRI tracked cell migration and localization. Behavioral recovery was evaluated via the corner test, modified neurological severity score (mNSS), and infarct volume analysis. Post-transplantation, Fer-RFP⁺ rMSCs were magnetically isolated for ex vivo electrophysiological and immunocytochemical analyses.
Ferucarbotran labeling did not impair rMSC viability and enhanced in vitro proliferation. MRI effectively visualized Fer-RFP⁺ rMSC migration to ischemic regions. Rats receiving Fer-RFP⁺ rMSCs showed significantly improved functional recovery and reduced infarct volumes compared to controls. Remarkably, ex vivo isolated Fer-RFP⁺ rMSCs exhibited spontaneous neuronal firing on multi-electrode array recordings and expressed the neuronal marker NeuN.
Ferucarbotran-labeled MSCs not only serve as MRI-visible tracers but also exhibit neuronal electrophysiological properties post-transplantation in an ischemic stroke model. The emergence of spontaneous neuronal firing in ex vivo transplanted MSCs suggests functional neuronal differentiation, potentially underpinning the observed therapeutic effects. These findings offer new mechanistic insights into MSC-mediated stroke recovery and may enhance the translational relevance of MSC-based therapies.
间充质干细胞（MSC）疗法在临床前缺血性中风模型中显示出前景，但临床转化结果仍不一致。为了填补这一空白，我们研究了用超顺磁性氧化铁（Ferucarbotran）标记MSC是否能够实现磁共振成像（MRI）追踪，并增强神经分化和功能整合，特别关注移植细胞中自发神经元放电活动这一新发现。
用红色荧光蛋白（RFP）转导大鼠MSC（rMSC），并用Ferucarbotran标记以生成Fer-RFP⁺ rMSC。将这些细胞移植到大脑中动脉闭塞的大鼠体内。MRI追踪细胞迁移和定位。通过转角试验、改良神经功能缺损评分（mNSS）和梗死体积分析评估行为恢复情况。移植后，通过磁性分离Fer-RFP⁺ rMSC进行体外电生理和免疫细胞化学分析。
Ferucarbotran标记不损害rMSC活力，并增强其体外增殖。MRI有效地可视化了Fer-RFP⁺ rMSC向缺血区域的迁移。与对照组相比，接受Fer-RFP⁺ rMSC的大鼠功能恢复明显改善，梗死体积减小。值得注意的是，体外分离的Fer-RFP⁺ rMSC在多电极阵列记录中表现出自发神经元放电，并表达神经元标志物NeuN。
Ferucarbotran标记的MSC不仅可作为MRI可见的示踪剂，而且在缺血性中风模型中移植后表现出神经元电生理特性。体外移植的MSC中出现自发神经元放电表明其发生了功能性神经元分化，这可能是观察到的治疗效果的基础。这些发现为MSC介导的中风恢复提供了新的机制见解，并可能增强基于MSC的疗法的转化相关性。
