Chung Jaehoon, Yamada Mayumi, Yang Phillip C
Stanford University School of Medicine, Stanford, California, USA.
Curr Protoc Stem Cell Biol. 2009 Aug;Chapter 5:Unit 5A.3. doi: 10.1002/9780470151808.sc05a03s10.
Magnetic resonance imaging (MRI) may emerge as an ideal non-invasive imaging modality to monitor stem cell therapy in the failing heart. This imaging modality generates any arbitrary tomographic view at high spatial and temporal resolution with exquisite intrinsic tissue contrast. This capability enables robust evaluation of both the cardiac anatomy and function. Traditionally, superparamagnetic iron oxide nanoparticle (SPIO) has been widely used for cellular MRI due to SPIO's ability to enhance sensitivity of MRI by inducing remarkable hypointense, negative signal, "blooming effect" on T2*-weighted MRI acquisition. Recently, manganese chloride (MnCl(2)) has been reported by our laboratory for its ability as a contrast agent to track biological activity of viable cells. Hyperintense, positive signals can be achieved from the Mn(2+)-labeled stem cells on T1-weighted MRI acquisition. Cytotoxicity is a potential drawback of Mn(2+) labeling of the cells. However, in our laboratory the labeling method has been optimized to minimize cytotoxic effects. This article describes two different magnetic labeling methods of human embryonic stem cells (hESC) using SPIO and MnCl(2).
磁共振成像（MRI）可能会成为监测衰竭心脏中干细胞治疗的理想无创成像方式。这种成像方式能够以高空间和时间分辨率生成任意断层图像，且具有出色的固有组织对比度。这种能力使得对心脏解剖结构和功能进行有力评估成为可能。传统上，超顺磁性氧化铁纳米颗粒（SPIO）已被广泛用于细胞MRI，因为SPIO能够通过在T2 *加权MRI采集中诱导显著的低信号、负信号“ blooming效应”来提高MRI的灵敏度。最近，我们实验室报道了氯化锰（MnCl₂）作为一种造影剂追踪活细胞生物活性的能力。在T1加权MRI采集中，Mn²⁺标记的干细胞可产生高信号、正信号。细胞毒性是细胞Mn²⁺标记的一个潜在缺点。然而，在我们实验室，标记方法已得到优化，以尽量减少细胞毒性作用。本文介绍了使用SPIO和MnCl₂对人胚胎干细胞（hESC）进行两种不同磁标记的方法。
