Imaging gene expression in regional brain ischemia in vivo with a targeted [111in]-antisense radiopharmaceutical.
Imaging gene expression in regional brain ischemia in vivo with a targeted [111in]-antisense radiopharmaceutical.
复制标题
使用靶向[111in]-反义放射性药物对体内局部脑缺血的基因表达进行成像。
DOI：
10.1162/15353500200404145
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发表时间：
2004
影响因子：
2.8
通讯作者：
Pardridge,WilliamM
中科院分区：
文献类型：
--
作者：
Suzuki,Toyofumi;Zhang,Yun;Zhang,Yu-Feng;Schlachetzki,Felix;Pardridge,WilliamM
编码胶质细胞酸性蛋白（GFAP）的基因在可逆性脑缺血（如大脑中动脉闭塞（MCAO））后24小时下调。用111 In标记的靶向肽核酸（PNA）与大鼠脑缺血GFAP mRNA的20-37位核苷酸杂交，观察脑缺血时GFAP基因表达下降的体内显像。PNA被单生物素化，并通过生物素-链霉亲和素连接与转铁蛋白受体（TfR）的单克隆抗体（MAb）连接。TfR单克隆抗体使PNA反义放射性药物从血液跨膜转运到脑细胞的胞质溶胶。通过免疫细胞化学证实了在1小时可逆性MCAO后24小时GFAP基因表达的降低。[111 In]-标记的PNA-MAb缀合物在1小时可逆性MCAO后24小时静脉内给予麻醉大鼠，并且相对于梗塞区外的脑区域，靶向反义显像剂的脑摄取减少。这些研究提供的证据表明，脑中靶基因表达的降低可以用序列特异性PNA在体内成像，只要反义放射性药物用受体特异性靶向剂穿过细胞膜递送。
The gene encoding glial fibrillary acidic protein (GFAP) is down-regulated 24 hr after reversible brain ischemia, such as with a middle cerebral artery occlusion (MCAO). The in vivo imaging of decreased GFAP gene expression in cerebral ischemia was examined in the present studies using a targeted peptide nucleic acid (PNA), which was labeled with111In, and which hybridized to nucleotides 20–37 of the rat GFAP mRNA. The PNA was monobiotinylated, and was attached to a monoclonal antibody (MAb) to the transferrin receptor (TfR) via a biotin–streptavidin linkage. The TfR MAb enablestrans-membrane transport of the PNA antisense radiopharmaceutical from blood to the cytosol of brain cells. The decreased GFAP gene expression at 24 hr after a 1-hr reversible MCAO was confirmed by immunocytochemistry. The [111In]-labeled PNA–MAb conjugate was administered intravenously to anesthetized rats at 24 hr after the 1-hr reversible MCAO, and the brain uptake of the targeted antisense imaging agent was decreased relative to brain regions outside of the infarct zone. These studies provide evidence that decreased expression of a target gene in brain can be imaged in vivo with a sequence-specific PNA, provided the antisense radiopharmaceutical is delivered across cell membranes with a receptor-specific targeting agent.