Comparison of reporter gene and iron particle labeling for tracking fate of human embryonic stem cells and differentiated endothelial cells in living subjects
Comparison of reporter gene and iron particle labeling for tracking fate of human embryonic stem cells and differentiated endothelial cells in living subjects
复制标题
DOI：
10.1634/stemcells.2007-0843
复制
发表时间：
2008-04-01
期刊：
影响因子：
5.2
通讯作者：
Wu, Joseph C.
中科院分区：
文献类型：
--
作者：
Li, Zongjin;Suzuki, Yoriyasu;Wu, Joseph C.
人类胚胎干细胞（human embryonic stem cells，hES）是一种多能干细胞，能够自我更新并分化为几乎所有的细胞类型。因此，它们作为再生疗法的细胞来源具有巨大的潜力。同时开发能够监测hES细胞体内植入的准确、灵敏和非侵入性技术，可以大大加快未来临床转化之前的基础研究。在这项研究中，hES细胞稳定转导慢病毒载体携带一种新的双融合报告基因，由萤火虫荧光素酶和增强的绿色荧光蛋白。报告基因表达对细胞活力、增殖或向内皮细胞（人胚胎干细胞衍生的内皮细胞[hESC-EC]）分化没有不良影响。为了比较两种流行的成像方式，在移植到小鼠后肢之前，用超顺磁性氧化铁颗粒共标记hES细胞和hESC-EC。纵向磁共振（MR）成像显示两个细胞群中存在持续长达4周的持续MR信号。相比之下，生物发光成像显示hES细胞和hESC-EC的不同信号模式。特别是，hESC-EC在第2天显示出显著的生物发光信号，其在随后的4周内逐渐降低，而来自未分化的hES细胞的生物发光信号在同一时期急剧增加。死后组织学和免疫组织化学证实畸胎瘤形成后注射未分化的hES细胞，但不是hESC-ECs。从这些数据一起，我们得出结论，报告基因是一个更好的标记，用于监测细胞活力，而铁颗粒标记是一个更好的标记，高分辨率检测细胞位置的MR。此外，移植预分化，而不是未分化的hES细胞将更适合于避免畸胎瘤的形成。
Human embryonic stem (hES) cells are pluripotent stem cells capable of self-renewal and differentiation into virtually all cell types. Thus, they hold tremendous potential as cell sources for regenerative therapies. The concurrent development of accurate, sensitive, and noninvasive technologies capable of monitoring hES cells engraftment in vivo can greatly expedite basic research prior to future clinical translation. In this study, hES cells were stably transduced with a lentiviral vector carrying a novel double-fusion reporter gene that consists of firefly luciferase and enhanced green fluorescence protein. Reporter gene expression had no adverse effects on cell viability, proliferation, or differentiation to endothelial cells (human embryonic stem cell-derived endothelial cells [hESC-ECs]). To compare the two popular imaging modalities, hES cells and hESC-ECs were then colabeled with superparamagnetic iron oxide particles before transplantation into murine hind limbs. Longitudinal magnetic resonance (MR) imaging showed persistent MR signals in both cell populations that lasted up to 4 weeks. By contrast, bioluminescence imaging indicated divergent signal patterns for hES cells and hESC-ECs. In particular, hESC-ECs showed significant bioluminescence signals at day 2, which decreased progressively over the following 4 weeks, whereas bioluminescence signals from undifferentiated hES cells increased dramatically during the same period. Postmortem histology and immunohistochemistry confirmed teratoma formation after injection of undifferentiated hES cells but not hESC-ECs. From these data taken together, we concluded that reporter gene is a better marker for monitoring cell viability, whereas iron particle labeling is a better marker for high-resolution detection of cell location by MR. Furthermore, transplantation of predifferentiated rather than undifferentiated hES cells would be more suited for avoiding teratoma formation.