Next Generation HSC Gene Therapy for HIV Control and Eradication

描述（由申请人提供）：U19的目标是开发下一代基因/细胞疗法来治疗HIV-1，并允许无药物控制病毒复制或根除。它汇集了学术和生物技术合作伙伴，在基因工程，病毒学，HSC生物学和移植，系统生物学和动物模型方面具有强大的合作历史和高度相关的专业知识。该项目还建立在该团队之前在HIV基因治疗方面的丰富经验基础上，特别是使用锌指核酸酶（ZFN）破坏CCR 5共受体，目前正在临床试验中进行评估。总体方法还通过最近关于HSC移植患者中HIV储库的性质的临床发现而被告知，例如“柏林患者”和两个“波士顿患者”。这些个体的对比结果表明，艾滋病毒抗性细胞在波士顿患者成功根除艾滋病毒中发挥了重要作用，并强调迫切需要更好地了解病毒储存库的性质，包括尽管完全免疫，但仍能持续存在的成分。 消融性移植方案。项目1将使用一个模型直接解决这个问题， 在猪尾猕猴中结合基因标记的自体和同种异体移植。 虽然正在进行的基于CCR 5破坏的试验提供了关于HIV基因治疗方法的一般可行性和有效性的重要信息，但通往更广泛临床应用的道路必须包括CCR 5以外的靶点。特别是，这将包括携带双重或X4嗜性病毒的患者。基于HSC的基因疗法也将受益于适当工程化细胞产生频率的改善，以及这些细胞对随后造血的贡献。为了实现这些目标，项目2、3和4将利用基因编辑和HSC扩增技术的最新发展，开发新的方法，并在人类和猕猴HSC中进行平行测试。具体而言，这些团队将协同工作，以开发以下能力：（1）最大限度地提高人类和灵长类HSC的基因编辑结果，（2）开发体外扩增工程HSC的方法，以及（3）评估基于位点特异性基因添加和内源性基因编辑的新型抗HIV策略。最后，项目4将使用猕猴模型直接解决扩大工程细胞对植入的贡献的方法是否可以使用适用于临床环境的低毒性预处理方案产生更有效的抗HIV作用。这项工作将得到三个核心的支持，提供行政监督，HSC移植的非人灵长类动物模型和结果的系统生物学分析。 总之，U19中的各个项目和核心将解决当前抗HIV基因/细胞疗法的主要缺点，从而指导未来疗法的开发，这些疗法具有已证实的疗效，增强的安全性和改善的HIV感染者实际应用潜力。

DESCRIPTION (provided by applicant): The goal of this U19 is to develop the next generation of gene/cell therapies to treat HIV-1 and allow drug-free control of virus replication or eradication. It brings together academic and biotech partners with a strong history of collaboration and highly relevant expertise in gene engineering, virology, HSC biology and transplantation, systems biology and animal models. The program also builds on the team's extensive prior experience with HIV gene therapy, in particular with the use of zinc finger nucleases (ZFNs) to disrupt the CCR5 co-receptor, which is currently being evaluated in clinical trials. The overall approach is also informed by recent clinical findings about the nature of HIV reservoirs in HSC transplant patients such as the "Berlin Patient" and the two "Boston Patients". The contrasting outcomes for these individuals point to an essential role for HIV-resistant cells in the Boston Patient's successful eradication of HIV and highlight the urgent need to better understand the nature of the viral reservoir, including component(s) that can persist despite fully ablative transplantation regimens. Project 1 will directly address this question using a model that combines gene-marked autologous and allogeneic transplantation in pig-tail macaques. While ongoing trials based on CCR5 disruption are providing important information about the general feasibility and efficacy of gene therapy approaches for HIV, the path towards broader clinical utility must include targets beyond CCR5. In particular, this will be so as to include patients harboring dual or X4-tropic viruses. HSC-based gene therapies will also benefit from improvements in both the frequency with which appropriately engineered cells can be produced, and the contribution of such cells to subsequent hematopoiesis. Towards these goals, Projects 2, 3 and 4 will exploit recent developments in gene editing and HSC expansion technologies to develop novel approaches that will be tested in parallel in human and macaque HSC. Specifically, the teams will work synergistically to develop capabilities to: (1) maximize gene editing outcomes in human and primate HSC, (2) develop methods to expand engineered HSC ex vivo, and (3) evaluate novel anti-HIV strategies based on site-specific gene addition and editing of endogenous genes. Finally, Project 4 will use the macaque model to directly address whether methods to expand the contribution of engineered cells to engraftment can lead to a more potent anti-HIV effect using the low toxicity conditioning regimens that will be appropriate in the clinical setting. The work will be supported by three Cores, providing administrative oversight, non-human primate models of HSC transplantation, and systems biology analysis of outcomes. In summary, the individual Projects and Core in this U19 will address the major shortcomings of current anti-HIV gene/cell therapies, and thereby guide the development of future therapies with demonstrated efficacy, enhanced safety, and improved potential for practical applications in HIV-infected individuals.