Immunologic Aspects of In Utero or Neonatal AAV-Based Gene Therapy

子宫内或新生儿基于 AAV 的基因治疗的免疫学方面

• 批准号: 8915936
• 负责人: Gerald S Lipshutz
• 金额: $ 51.27万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2017-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8915936
• 关键词: Acids; Adjuvant; Alpha-glucosidase; Antibodies; Antigens; Area; Behavior Therapy; Birth; Blood Coagulation Factor; Chickens; Child; Data; Dependovirus; Development; Diagnosis; Disease; Early treatment; Experimental Models; Exposure to; Factor VIII; Failure; Fatal Outcome; Fetal Development; Fetus; Firefly Luciferases; First Pregnancy Trimester; Future; Gene Therapy Agent; Gene Transfer Techniques; Glycogen storage disease type II; Goals; Growth; Health; Hemophilia A; Hemorrhage; Hereditary Disease; Human; Immune Tolerance; Immune response; Immune system; Immunity; Immunologics; Immunologist; Inborn Genetic Diseases; Individual; Infusion procedures; Inherited; Intervention; Investigation; Joints; Life; Macaca mulatta; Maintenance; Methods; Modeling; Monkeys; Mus; Muscle; Neonatal; Neuromuscular Diseases; Newborn Infant; Ovalbumin; Pathologic; Patients; Plasma; Prevention; Primates; Prophylactic treatment; Proteins; Publishing; Recombinant Proteins; Recombinants; Research; Serotyping; Staging; T-Lymphocyte; Testing; Time; Transgenes; Viral Proteins; Viral Vector; Weight Gain; Work; adeno-associated viral vector; anergy; arginase; base; bioluminescence imaging; enzyme replacement therapy; fetal; gene replacement; gene therapy; human F8 protein; immunogenic; in utero; infancy; inhibitor/antagonist; insight; neonate; nonhuman primate; postnatal; prenatal; prevent; protein expression; rapid growth; response; standard of care; success; transgene expression; vector

DESCRIPTION (provided by applicant): The introduction and expression of a normal protein by gene transfer techniques may result in the development of neutralizing immune responses as the normal protein may be recognized as non-self in those with inherited disorders of proteins. The success of gene therapy is dependent on the development of a state of immunological tolerance or anergy to protein products; achieving this could have an impact on the treatment of human disorders of secretory or intracellular proteins and neuromuscular disorders where inhibitory antibodies can develop; this remains an important and unresolved issue with present day protein-based therapy and future gene therapy trials. While mice have been the experimental model for most immunologists and the study of the murine immune response has yielded important insights, the failure of these models to predict the efficacy of gene therapy in humans is a major limitation. Accordingly, the current proposal will study the immune response to xenogenic transgene-encoded proteins expressed by AAV vectors in the nonhuman primate where the ontogeny on the immune system is similar to humans, and test the hypothesis that exposure to these persistent antigens, beginning either in utero or in the early neonatal period, will result in the induction of immunological tolerance. In addition, AAV expressing xenogenic factor VIII will be administered to the monkey fetus and neonate as a model for hemophilia A gene therapy to prevent inhibitor development to factor VIII, the treatment goal for this area of investigation. Preliminary data: Our research group has administered AAV expressing ovalbumin, an immunogenic and well- characterized protein, to newborn monkeys and have demonstrated a lack of immune response to this xenogenic protein while protective immunity to AAV has remained intact; augmented expression was possible with subsequent postnatal AAV administration without a humoral response to the xenogenic protein but did require AAV serotype switching. In Aim 1, AAV will be administered in utero and to neonatal nonhuman primates to study the mechanism of immune unresponsiveness to the foreign transgene-encoded protein. In Aim 2, we will assess the immune response to the viral vector administered in utero and the neonate. Finally, we will assess immune responses to the xenogenic factor VIII as a model for hemophilia A gene therapy and inhibitor formation prevention. These studies will determine if a clinically acceptable method to establish tolerance to immunogenic proteins is possible by initiating transgene expression while immunologic ontogeny may not be completely developed in a nonhuman primate model that could replicate a strategy for human intervention.

描述（由申请人提供）：通过基因转移技术引入和表达正常蛋白质可能导致中和免疫反应的发展，因为在患有蛋白质遗传性疾病的人中正常蛋白质可能被识别为非自身蛋白质。基因治疗的成功取决于对蛋白质产品的免疫耐受或无反应状态的发展；实现这一目标可能会对人类分泌或细胞内蛋白质疾病以及可产生抑制性抗体的神经肌肉疾病的治疗产生影响；对于当今基于蛋白质的治疗和未来的基因治疗试验来说，这仍然是一个重要且未解决的问题。虽然小鼠一直是大多数免疫学家的实验模型，并且对小鼠免疫反应的研究已经产生了重要的见解，但这些模型未能预测基因治疗在人类中的功效是一个主要限制。因此，当前的提案将研究非人灵长类动物对 AAV 载体表达的异种转基因编码蛋白的免疫反应，其中免疫系统的个体发育与人类相似，并测试暴露于这些持久性抗原的假设，从在子宫内或新生儿早期，会导致免疫耐受的诱导。此外，表达异种因子 VIII 的 AAV 将被施用于猴胎儿和新生儿，作为血友病 A 基因治疗的模型，以防止抑制剂发展为因子 VIII，这是该研究领域的治疗目标。初步数据：我们的研究小组已对新生猴子施用表达卵清蛋白（一种免疫原性且特征明确的蛋白质）的 AAV，并已证明对这种异种蛋白质缺乏免疫反应，而对 AAV 的保护性免疫仍然完好无损；随后出生后施用 AAV 可能会增强表达，而不会对异种蛋白产生体液反应，但确实需要 AAV 血清型转换。在目标 1 中，AAV 将在子宫内和新生非人灵长类动物中施用，以研究对外源转基因编码蛋白的免疫无反应机制。在目标 2 中，我们将评估对子宫内和新生儿施用的病毒载体的免疫反应。最后，我们将评估对异种因子 VIII 的免疫反应，作为甲型血友病基因治疗和抑制剂形成预防的模型。这些研究将确定是否可以通过启动转基因表达建立临床上可接受的方法来建立对免疫原性蛋白质的耐受性，而免疫个体发育可能无法在可以复制人类干预策略的非人类灵长类动物模型中完全发展。