Antisense imaging of brain gene expression in vivo

描述（由申请人提供）： 人类基因组的排序将导致检测到成千上万的 在脑癌和其他癌症中独特表达的基因 机关在脑癌中独特表达的基因可以用来指导 新形式的诊断和治疗策略，如果有可能， 开发一种新的技术，用于成像体内大脑中的基因表达。 需要能够对基因表达进行成像的技术，因为它 将不可能使患者接受重复的开颅手术， 组织样本特定基因成像的唯一方法是 反义放射性药物然而，这些分子不跨细胞 膜良好，不穿过血脑屏障（BBB）。它可能是 可以使用反义放射性药物来成像基因表达，如果 这些分子可通过血脑屏障转运。这将需要 开发了应用于反义分子的脑靶向技术， 这是本申请的主题。在这种方法中， 反义放射性药物与BBB药物靶向系统缀合。的 靶向载体是针对BBB的拟肽单克隆抗体（MAb 转铁蛋白受体（TfR）。这种单克隆抗体经历受体介导的转胞吞作用 通过内源性血脑屏障转铁蛋白受体。模型反义分子， 将在这些研究中使用的是肽核酸（PNA），因为先前的肽核酸（PNA）是肽核酸。 工作表明，这种类型的反义具有理想的特性， 与其他反义分子相比。的缀合 促进了反义放射性药物与药物靶向载体的结合 使用抗生物素蛋白-生物素技术。在这项工作的R21阶段， 将进行内源性基因的成像，并且靶mRNA将是内源性的。 在实验性脑肿瘤中过度表达的基因产物。第二 这些研究的第三阶段（R33）将扩展成像技术，包括[ 11 L-铟]反义放射性药物和体内验证 用原位杂交进行平行的体外测量成像。如果 如果成功，这些研究将为一种新技术提供基础， 能够在体内对大脑中的基因表达进行非侵入性成像。这 技术可以扩展到人类和其他器官。而目前 是没有平行的技术，使非侵入性的体内成像， “任何人的任何基因”，这是这项工作的目标。

DESCRIPTION (provided by applicant): The sequence of the human genome will lead to the detection of thousands of genes that are uniquely expressed in cancer of the brain as well as other organs. The genes uniquely expressed in brain cancer could be used to guide new forms of diagnosis and therapeutic strategies if it was possible to develop a new technology for imaging gene expression in the brain in vivo. Technology that enables the imaging of gene expression is needed because it will not be possible to subject patients to repeated craniotomies to obtain tissue samples. The only way that specific genes can be imaged is with antisense radiopharmaceuticals. However, these molecules do not cross cell membranes well and do not cross the blood-brain barrier (BBB). It could be possible to use antisense radiopharmaceuticals to image gene expression, if these molecules were transportable through the BBB. This will require the development of brain targeting technology applied to antisense molecules, which is the subject of the present application. In this approach, the antisense radiopharmaceutical is conjugated to BBB drug targeting systems. The targeting vector is a peptidomimetic monoclonal antibody (MAb) to the BBB transferrin receptor (TfR). This MAb undergoes receptor-mediated transcytosis through the BBB via the endogenous BBB TfR. The model antisense molecule that will be used in these studies is a peptide nucleic acid (PNA) because prior work has shown that this type of antisense has ideal characteristics for imaging compared to other antisense molecules. The conjugation of the antisense radiopharmaceuticals to the drug targeting vector is facilitated with the use of avidin- biotin technology. In the R21 phase of this work, the imaging of an endogenous gene will be performed and the target mRNA will be a gene product that is over-expressed in experimental brain tumors. The second phase of these studies (R33) will extend the imaging technologies to include [ 11 l-indium] antisense radiopharmaceuticals and validation of the in vivo imaging with parallel in vitro measurements with in situ hybridization. If successful, these studies will provide the basis for a new technology that enables non-invasive imaging of gene expression in the brain in vivo. This technology could be extended to humans and to other organs. At present, there is no parallel technology that enables the non-invasive in vivo imaging of "any gene in any person," which is the goal of this work.