本研究的目的是以開發氧化鐵奈米粒子(ION)標記人類間質幹細胞 (MSCs)誘導體外分化成為類神經細胞 (NCs) 的應用以及在核磁共振成像（MRI）之追蹤表現。Ferucarbotran，一種臨床所使用的氧化鐵奈米粒子，此種陰性顯影劑可以在核磁共振成像下清楚的看見，因此被用來標記細胞內的追蹤觀察。本研究透過光學顯微鏡下發現體外培養的類神經細胞具有神經細胞的型態以及量測動作電位的功能表現。在光學顯微鏡下觀察到細胞呈現軸突樣的結構型態。這些類神經細胞比未分化的間質幹細胞表現較多頻率的動作電位。以氧化鐵奈米粒子標記對間質幹細胞的形態、功能和分化能力沒有影響。我們的結論發現，以體外誘導人類間質幹細胞 (MSCs)分化成的類神經細胞 (NCs) 表現較多頻率的動作電位，或許這些體外誘導生成的類神經細胞可以用於替代損傷的神經元。

The aim of the current study was to develop an iron oxide nanoparticle (ION) labelling and magnetic resonance imaging (MRI)-based protocol to allow visualization of the differentiation process of mesenchymal stem cells (MSCs) into neural-like cells (NCs) in vitro. Ferucarbotran, a clinically available ION, which can be visualized under MRI, is used for tracking cells implanted in vivo. The NCs were verified morphologically and histologically by light microscopy, and their functions were verified by measuring their action potentials. Conformational conversion of axon-like structures was observed under light microscopy. These NCs exhibited frequent, active action potentials compared with cells that did not undergo neural differentiation. The labelling of ION had no influence on the morphological and functional differentiation capacity of the MSCs. We conclude that the MSCs that were differentiated into NCs exhibited in vitro activity potential firing and may be used to replace damaged neurons.

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