Departments of Radiology and Experimental Diagnostic Imaging, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030-4009, USA.
Mol Imaging. 2009 Dec;8(6):319-29.
Our purpose was to enable an in vivo imaging technology that can assess the anatomy and function of peripheral nerve tissue (neurography). To do this, we designed and tested a fluorescently labeled molecular probe based on the nontoxic C fragment of tetanus toxin (TTc). TTc was purified, labeled, and subjected to immunoassays and cell uptake assays. The compound was then injected into C57BL/6 mice (N = 60) for in vivo imaging and histologic studies. Image analysis and immunohistochemistry were performed. We found that TTc could be labeled with fluorescent moieties without loss of immunoreactivity or biologic potency in cell uptake assays. In vivo fluorescent imaging experiments demonstrated uptake and retrograde transport of the compound along the course of the sciatic nerve and in the spinal cord. Ex vivo imaging and immunohistochemical studies confirmed the presence of TTc in the sciatic nerve and spinal cord, whereas control animals injected with human serum albumin did not exhibit these features. We have demonstrated neurography with a fluorescently labeled molecular imaging contrast agent based on the TTc.
我们的目的是开发一种能够评估周围神经组织（神经造影术）解剖结构和功能的体内成像技术。为此，我们设计并测试了一种基于破伤风毒素（TTc）无毒 C 片段的荧光标记分子探针。TTc 经过纯化、标记，并进行了免疫测定和细胞摄取测定。然后将该化合物注射到 C57BL/6 小鼠（N = 60）中进行体内成像和组织学研究。进行了图像分析和免疫组织化学分析。我们发现 TTc 可以用荧光部分标记，而在细胞摄取测定中不会丧失免疫反应性或生物效力。体内荧光成像实验表明，该化合物沿着坐骨神经和脊髓的路径被摄取并逆行转运。离体成像和免疫组织化学研究证实了 TTc 存在于坐骨神经和脊髓中，而注射人血清白蛋白的对照动物则没有这些特征。我们已经用基于 TTc 的荧光标记分子成像对比剂证明了神经造影术的可行性。
