IMMUNOLOGY AND BIOLOGY OF PEGYLATED ADENOVIRUS AFTER A SINGLE DOSE

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 基因治疗领域的主要挑战之一是开发高效、安全的基因递送系统。虽然腺病毒是目前用于基因治疗的最广泛研究的病毒之一，但由于它们能够诱导强烈的免疫反应，这些载体的临床应用受到了限制。这种反应可能危及患者的健康，限制转基因表达的长度，并在重新注射病毒时禁止基因表达。通过去除所有病毒序列而开发的“内脏”或辅助依赖的腺病毒(HD-Ad)载体显著降低了与病毒相关的毒性，但宿主对衣壳蛋白的反应在给药后不久仍会引起严重的副作用，这是临床治疗所必需的。这种影响在临床前测试中常用的啮齿动物模型中看不到。然而，这些影响在非人类灵长类动物中是相当深刻的，这表明该动物模型更适合于在临床上预测媒介的性能。 在这些研究中，将静脉注射低剂量(5x1011病毒颗粒(Vp/kg))、中剂量(3x1012Vp/kg)或高剂量(1x1013)的聚乙二醇化腺病毒。接受来自相同制剂的类似剂量的未经修改的病毒的动物将作为对照。在接种病毒前和接种后4天内采集血样，进行血细胞计数、血液化学和细胞因子分析以及抗腺病毒抗体的测定。动物将在接种病毒四天后被安乐死，并采集所有器官，以评估未经修饰的病毒和聚乙二醇化病毒之间的全身分布模式的差异。这些研究的结果可能会对腺病毒介导的基因转移在临床上的使用产生重大影响。它们还将为治疗遗传病的其他改良病毒的额外临床前测试提供宝贵的初步数据。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. One of the major challenges in the field of gene therapy is the development of efficient and safe gene delivery systems. Although adenoviruses are one of the most extensively studied viruses currently utilized for gene therapy applications, clinical use of these vectors has been limited due to their ability to elicit a strong immune response. This response can compromise the patient's health, limit the length of transgene expression and prohibit gene expression upon re-administration of the virus. Development of "gutted", or helper-dependent, adenoviral (HD-Ad) vectors by removing all viral sequences has significantly reduced the toxicity associated with the virus, but the host response against capsid proteins can still induce severe side effects soon after administration of doses necessary for clinical treatment. This effect is not seen in rodent models commonly used in pre-clinical testing. These effects are, however, quite profound in non-human primates suggesting that this animal model is more suitable for predicting vector performance in the clinic. In these studies, baboons will be given either a low (5 x 1011 virus particles (vp/kg)) intermediate (3 x 1012 vp/kg) or high does (1 x 1013) of PEGylated adenovirus by intravenous injection. Animals receiving similar doses of unmodified virus from the same preparation will serve as controls. Blood samples will be taken prior to administration of virus and for a period of 4 days after administration for blood cell counts, blood chemistry and cytokine analysis sand measurement of anti-adenovirus antibodies. Animals will be euthanized four days after administration of the virus and all organs harvested for assessment of differences in whole-body distribution patterns between unmodified and PEGylated virus. Results from these studies could have significant impact on the use of adenovirus-mediated gene transfer in the clinic. They will also provide valuable preliminary data for additional pre-clinical testing of other modified viruses for the treatment of genetic disease.