Enhancing immune regulation in gene therapy for hemophilia

增强血友病基因治疗中的免疫调节

• 批准号: 9721569
• 负责人: Ype Peter De Jong
• 金额: $ 70.88万
• 依托单位: INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-06-13 至 2020-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9721569
• 关键词: Antigen-Antibody Complex; Antigen-Presenting Cells; Antigens; Benchmarking; Birth; Blood Coagulation Factor; CD8-Positive T-Lymphocytes; CX3CL1 gene; Capsid; Cell Therapy; Cells; Clinical; Clinical Data; Clinical Trials; Clinical assessments; Coagulation Process; Complex; Data; Dendritic Cells; Development; Disease; Ensure; Equilibrium; F8 gene; FLT3 ligand; FOXP3 gene; Future; Gene Transfer; Genome; Goals; Hemophilia A; Hemophilia B; Hepatic; Hepatocyte; Homeostasis; Human; IL2RA gene; Immune; Immune Tolerance; Immune response; Immune system; Immunologics; Interleukin-10; KDR gene; Laboratories; Ligands; Literature; Liver; Modeling; Morbidity - disease rate; Mus; Outcome; Patients; Peptides; Phase; Prothrombin; Protocols documentation; Regulatory Pathway; Regulatory T-Lymphocyte; Risk; Sirolimus; System; T cell response; Testing; Therapeutic; Transforming Growth Factor beta; Transgenes; Translations; Ursidae Family; Vascular Endothelial Growth Factors; Viral; Viral Genes; adaptive immune response; adeno-associated viral vector; antibody inhibitor; base; cost; empowered; experimental study; gene therapy; immune activation; immunogenic; immunogenicity; immunoregulation; improved; in vivo; male; migration; mouse model; next generation; novel; overexpression; pre-clinical; receptor; reconstitution; response; success; synergism; tool; transgene expression; vector

Project Summary / Abstract Adeno-associated viral (AAV) gene transfer represents a promising treatment for hemophilia, showing first success in Phase I/II clinical trials with long-term systemic coagulation FIX expression in patients with hemophilia B. However, CD8+ T cell responses to input viral capsid antigen have emerged as a substantial hurdle. In addition, treatment of hemophilia generally bears a risk for inhibitory antibody (inhibitor) formation against the therapeutic clotting factor. While our pre-clinical data have shown the ability of hepatic AAV gene transfer to induce immune tolerance to FIX, moving forward toward the more immunogenic FVIII in gene therapy for hemophilia A remains a challenge. The complex problems of immune rejection of vector or transgene product require a multi-pronged approach of synergistic strategies aimed at reducing immunogenicity of the vector and at activation of immune regulatory pathways that serve as a “backup mechanism” to suppress adaptive immune responses that may still occur, ultimately accomplishing long-term immune tolerance and thereby assuring sustained therapy. The focus of this proposal is the development of strategies and protocols for suppression of unwanted immune responses by regulatory T cells (Treg), and to create conditions that enhance immune regulation, including induction, expansion, and migration of Treg. Previously, we established that induction of CD4+CD25+FoxP3+ Treg by hepatocyte-derived transgene expression is crucial for tolerance to the transgene product upon liver-directed gene transfer. Here, we will continue to exploit the mechanisms that define the interplay between Treg and dendritic cells to induce and expand FoxP3+ Treg and alternative Treg (CD4+CD25-LAP+ and Tr1 cells). By improving induction and expansion of Treg, and their ability to migrate, we empower these cells to optimally control unwanted immune responses to vector and transgene product. Proposed experiments are grouped in the following specific aims: Aim 1: Dissect the mechanisms by which expansion and migration to the liver of FoxP3+ Treg, Tr1, or LAP+ Treg cells can be triggered by ligands of the receptors GITR, CX3CR1 and VEGFR. Aim 2: Test the hypothesis that empowering by plasmacytoid and CX3CR1+ dendritic cells promotes expansion and migration of Treg cells in the liver in hepatic AAV gene transfer for hemophilia. Aim 3: Develop immune tolerance protocols based on the alternative and synergistic use of distinct subsets of Treg cells: FoxP3+ Treg, Tr1 and/or LAP+ Treg cells. Aim 4: Develop an in vivo system that enables studies of immune responses and regulation to liver gene transfer with human hepatocytes and immune cells.

项目总结/摘要 腺相关病毒（AAV）基因转移代表了血友病的一种有前途的治疗方法， 在患有以下疾病的患者中长期全身凝血FIX表达的I/II期临床试验中取得成功： 血友病B。然而，CD 8 + T细胞对输入病毒衣壳抗原的应答已经成为一种实质性的免疫应答。 障碍物此外，血友病的治疗通常具有抑制性抗体（抑制物）形成的风险 对抗治疗性凝血因子虽然我们的临床前数据表明，肝AAV基因的能力 转移以诱导对FIX的免疫耐受，向基因中更具免疫原性的FVIII迈进 血友病A的治疗仍然是一个挑战。免疫排斥反应的复杂问题， 转基因产品需要一种多管齐下的协同策略， 载体的免疫原性和作为“备份”的免疫调节途径的激活 这种机制”抑制可能仍然发生的适应性免疫反应，最终实现长期免疫。 免疫耐受，从而确保持续治疗。该提案的重点是发展 通过调节性T细胞（Treg）抑制不需要的免疫应答的策略和方案，以及 创造增强免疫调节的条件，包括Treg的诱导、扩增和迁移。 先前，我们已经确定了通过肝细胞来源的转基因诱导CD 4 + CD 25 + FoxP 3 + Treg， 表达对于肝定向基因转移后转基因产物的耐受性是至关重要的。在这里，我们将 继续利用定义Treg和树突状细胞之间相互作用的机制来诱导和 扩增FoxP 3 + Treg和替代性Treg（CD 4 + CD 25-Treg+和Tr 1细胞）。通过改进归纳和 Treg的扩增及其迁移能力，我们使这些细胞能够最佳地控制不需要的免疫反应。 对载体和转基因产物的应答。拟议的实验按以下具体目标分类： 目的1：探讨FoxP 3 + Treg、Tr 1或FoxP 3 + Treg在肝细胞中的扩增和迁移机制。 Treg细胞可由受体GITR、CX 3CR 1和VEGFR的配体触发。 目的2：检验浆细胞样和CX 3CR 1+树突状细胞增强能力促进 在用于血友病的肝AAV基因转移中Treg细胞在肝中的扩增和迁移。 目标3：基于不同子集的替代和协同使用，开发免疫耐受方案 Treg细胞：FoxP 3 + Treg、Tr 1和/或FoxP 3 + Treg细胞。 目的4：建立一个研究肝脏基因对免疫应答和调控的体内系统 与人肝细胞和免疫细胞一起转移。