Blocking the immune response to Helper-dependent adenovirus vector for Hemophilia

描述（由申请人提供）：项目名称。阻断辅助型腺病毒介导的免疫应答以改进血友病A基因治疗。项目摘要。 血友病A（Hemophilia A，HA）是一种常见的凝血功能障碍性疾病，由凝血因子VIII（Factor VIII，FVIII）缺乏引起。主要的治疗方法是使用重组人FVIII进行替代治疗。然而，由于高成本、获得治疗和抑制性抗体形成，患者继续遭受显著的长期发病率和死亡率。我们开发了优化的辅助病毒依赖性腺病毒基因载体（HDAds）系统，使我们能够使用小型和大型动物模型实现分泌型和细胞内转基因的长期表达，而没有慢性毒性和载体的持久性。然而，急性毒性仍然是临床转化的障碍。为了克服这一点，我们提出开发表达SOCS 1和/或编码TLR 9抑制剂序列的免疫抑制性HDAs。然而，由于先天免疫系统的巨大冗余，我们建议开发血液滤过形式的连续治疗，该治疗在败血症背景下已经具有临床益处，可清除急性免疫成分。我们将在非人灵长类动物的安全性研究中将联合收割机血液滤过与改进的免疫抑制HDAs相结合。最终，我们将应用这种方法的临床前治疗FVIII缺乏症的小鼠和犬HA。为了解决FVIII治疗的潜在适应性免疫应答，我们将共表达血管性血友病因子（vWF）与FVIII。通过这些研究，我们将解决血友病A基因治疗中的三个重要问题i）我们能否降低对HDAs的先天免疫反应？ii）我们能否提高HA模型中FVIII表达的功效？iii）我们能用连续性血液滤过降低非人灵长类动物模型的先天免疫应答吗？本申请的总体目标是建立安全有效的HA基因治疗，辅助依赖性腺病毒载体（HDAs）结合血液滤过，可以很容易地在临床竞技场转化为未来的临床试验。 在该指导阶段（K99），我将通过结合先天免疫应答的细胞自主免疫抑制、非细胞自主体液因子的物理清除和FVIII的稳定因子来提高HA治疗的HDAd治疗指数。指导阶段（K99）将在贝勒医学院的指导下进行。在随后的独立研究者阶段（R 00），我将把这种混合HDAs应用于犬HA，为临床研究做准备。我还将评价血液滤过辅助混合HDAs注射在非人灵长类动物中的治疗效果。 公共卫生相关性：项目叙述。 血友病A（Hemophilia A，HA）是一种常见的凝血功能障碍性疾病，由凝血因子VIII（Factor VIII，FVIII）缺乏引起。主要的治疗方法是使用重组人FVIII进行替代治疗。然而，由于高成本、获得治疗和抑制性抗体形成，患者继续遭受显著的长期发病率和死亡率。本申请的总体目标是用辅助依赖性腺病毒载体建立安全有效的HA基因治疗，当与新的物理干预（如血液滤过）组合时，可以在临床竞技场中容易地转化用于未来的临床试验。

DESCRIPTION (provided by applicant): Project Title. Blocking the immune response to Helper-dependent adenovirus vector for improved Hemophilia A gene therapy. Project Abstract. Hemophilia A (HA) is a common disorder of coagulation caused by deficiency of factor VIII (FVIII). The mainstay of treatment has been replacement therapy with recombinant human FVIII. However, because of high cost, access to therapy, and inhibitory antibody formation, patients continue to suffer from significant long-term morbidity and mortality. Our development of an optimized helper-dependent adenoviral gene vector (HDAds) system has enabled us to achieve long term expression of both secreted and intracellular transgenes without chronic toxicity and persistence of vector using both small and large animal models. However, acute toxicity remains an obstacle to clinical translation. To overcome this, we propose to develop immune suppressive HDAds expressing SOCS1 and/or coding TLR9 inhibitor sequences. However, because of the great redundancy of the innate immune system, we propose to develop adjunctive therapy in the form of hemofiltration that has already to be clinically-beneficial to remove the acute immune components in the context of sepsis. We will combine hemofiltration with improved immunosuppressive HDAds in safety studies in nonhuman primates. Ultimately, we will apply this approach to the preclinical treatment of FVIII deficiency in murine and canine HA. To address the potential adaptive immune response to FVIII therapy, we will co-express von Willebrand Factor (vWF) with FVIII. With these studies, we will address three important questions in genetic therapy for hemophilia A i) Can we decrease the innate immune response to HDAds? ii) Can we improve the efficacy of FVIII expression in HA model? iii) Can we decrease the innate immune response in nonhuman primate model with adjunctive hemofiltration? The overall goal of this application is to establish the safe and effective HA gene therapy with helper-dependent adenoviral vectors (HDAds) combined with hemofiltration that can be readily translated in the clinical arena for future clinical trials. During this mentored phase (K99), I will improve the therapeutic index of HDAd for HA therapy by combining cell autonomous immune suppression of the innate immune response, physical clearance of non-cell autonomous humoral factors, and stabilization factor of FVIII,. The mentored phase (K99) will occur at Baylor College of Medicine under the guidance of Dr. Brendan Lee. In the subsequent independent investigator phase (R00), I will apply this hybrid HDAds to canine HA in preparation for clinical studies. I will also evaluate the therapeutic effect of hemofiltration-assisted hybrid HDAds injection in nonhuman primates. PUBLIC HEALTH RELEVANCE: Project Narrative. Hemophilia A (HA) is a common disorder of coagulation caused by deficiency of factor VIII (FVIII). The mainstay of treatment has been replacement therapy with recombinant human FVIII. However, because of high cost, access to therapy, and inhibitory antibody formation, patients continue to suffer from significant long-term morbidity and mortality. The overall goal of this application is to establish the safe and effective HA gene therapy with helper-dependent adenovirus vector which, when combined with novel physical interventions (such as hemofiltration) that can be readily translated in the clinical arena for future clinical trials.