Targeting virus-specific CAR T cells to lymphoid follicles to achieve durable HIV suppression

将病毒特异性 CAR T 细胞靶向淋巴滤泡以实现持久的 HIV 抑制

• 批准号: 10284935
• 负责人: PAMELA J SKINNER
• 金额: $ 71.49万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-11-13 至 2023-10-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10284935
• 关键词: Aftercare; Animals; Anti-Retroviral Agents; Antibodies; Autologous; B-Lymphocytes; BLR1 gene; CD4 Positive T Lymphocytes; CD8-Positive T-Lymphocytes; Cells; Control Animal; Cyclophosphamide; Data; Disease remission; Goals; HIV; HIV Infections; HIV-1; Homing; Human; Immune; Immunotherapy; In Vitro; Infection; Interruption; Intervention; Lymphoid Follicle; Lymphoid Tissue; MS4A1 gene; Macaca; Macaca mulatta; Patients; Pharmaceutical Preparations; RNA; Regimen; SIV; Site; T cell response; T-Lymphocyte; Testing; Time; Viral; Viral Load result; Viral reservoir; Viremia; Virus; Virus Replication; anti-viral efficacy; chimeric antigen receptor T cells; improved; in vivo; insight; novel; preconditioning; trafficking; treatment strategy; viral rebound

Abstract Virus-specific CD8 T cells exert potent antiviral activity against HIV-1 and SIV both in vitro and in vivo. Nevertheless, despite abundant CD8 T cell responses in HIV-1-infected humans and SIV- infected macaques, they are unable to fully suppress virus replication. This is likely due to the majority of HIV-1 and SIV replication occurring in CD4+ T cells concentrated within B-cell follicles in secondary lymphoid tissues; where virus-specific CD8 T cells are relatively few in number. In fact, we found that in vivo effector virus-specific CD8 T cell to target SIV RNA+ cell ratios (E:T) were over 40-fold lower inside compared to outside of B cell follicles in lymphoid tissues during SIV infection in rhesus macaques. These findings indicate that B cell follicles are an immune privileged site in which low levels of virus-specific CD8 T cells permit ongoing viral replication. Furthermore, we found that the majority of virus-specific CD8 T cells fail to express the follicular homing molecule CXCR5, likely explaining low levels of virus-specific CD8 T cells localizing to and surveilling B cell follicles. Taken together these data suggest that the inability of HIV- and SIV- specific CD8 T cells to fully suppress virus replication may be due to a deficiency of virus-specific CD8 T cells in B-cell follicles. These findings have led us to our central hypothesis that targeting HIV-specific T cells to B cell follicles will lead to durable remission of HIV infection. In support of this hypothesis we have shown, in SIV-infected rhesus macaques, that increased levels of virus-specific CD8 T cells in B cell follicles is associated with lower viral loads. To test this hypothesis, we propose to evaluate a T cell immunotherapy product that targets virus- specific CD8 T cells to B cell follicles. We are calling this product CD4-MBL-CAR/CXCR5 T cell immunotherapy. Our long-term goal is to develop an intervention that will lead to durable remission of HIV infection. To test this central hypothesis, we propose the following two specific aims. 1) To determine the in vivo localization, persistence and antiviral efficacy of autologous CD4-MBL- CAR/CXCR5 T cells infused into antiretroviral drug (ART) suppressed rhesus macaques before and after treatment interruption. 2) To determine whether preconditioning with CD20 antibodies (instead of cyclophosphamide) improves the abundance, persistence, or antiviral efficacy of autologous CAR/CXCR5-transduced CD8 T cells infused into ART suppressed rhesus macaques before and after treatment interruption. Our proposed studies targeting virus-specific CAR T cells to follicles will have a broad impact on the field by providing insights into cell trafficking, persistence, and pre-conditioning regimens for immunotherapy approaches. Most importantly, these studies could result in an effective strategy to induce long-term sustained remission of HIV.

抽象的 病毒特异性 CD8 T 细胞在体外和体内均对 HIV-1 和 SIV 发挥有效的抗病毒活性 体内。然而，尽管 HIV-1 感染者和 SIV- 感染者体内存在丰富的 CD8 T 细胞反应， 受感染的猕猴，它们无法完全抑制病毒复制。这可能是由于 大多数 HIV-1 和 SIV 复制发生在 CD4+ T 细胞中，集中在 B 细胞滤泡内 在次级淋巴组织中；其中病毒特异性 CD8 T 细胞的数量相对较少。在 事实上，我们发现体内效应病毒特异性 CD8 T 细胞与目标 SIV RNA+ 细胞的比率 (E:T) SIV 期间淋巴组织中的 B 细胞滤泡内部比外部低 40 倍以上 恒河猴感染。这些发现表明 B 细胞滤泡具有免疫特权 低水平的病毒特异性 CD8 T 细胞允许病毒持续复制的位点。此外， 我们发现大多数病毒特异性 CD8 T 细胞无法表达滤泡归巢 CXCR5 分子，可能解释了低水平的病毒特异性 CD8 T 细胞定位于 和 监测 B 细胞滤泡。总而言之，这些数据表明 HIV 和 SIV 无法 特异性 CD8 T 细胞完全抑制病毒复制可能是由于缺乏病毒特异性 B 细胞滤泡中的 CD8 T 细胞。这些发现使我们得出了我们的中心假设： 将 HIV 特异性 T 细胞靶向 B 细胞滤泡将导致 HIV 持久缓解 感染。为了支持这一假设，我们在感染 SIV 的恒河猴中证明， B 细胞滤泡中病毒特异性 CD8 T 细胞水平的增加与较低的病毒载量相关。 为了检验这一假设，我们建议评估一种针对病毒的 T 细胞免疫治疗产品 B 细胞滤泡的特异性 CD8 T 细胞。我们将此产品称为 CD4-MBL-CAR/CXCR5 T 细胞 免疫疗法。我们的长期目标是开发一种干预措施，以实现持久缓解 艾滋病毒感染。为了检验这一中心假设，我们提出以下两个具体目标。 1) 至 确定自体 CD4-MBL- 的体内定位、持久性和抗病毒功效 之前注入抗逆转录病毒药物（ART）的 CAR/CXCR5 T 细胞可抑制恒河猴 以及治疗中断后。 2) 判断是否用CD20抗体进行预处理 （代替环磷酰胺）提高了丰度、持久性或抗病毒功效 将自体 CAR/CXCR5 转导的 CD8 T 细胞注入 ART 抑制的恒河猴中 治疗中断之前和之后。我们提出的针对病毒特异性 CAR T 细胞的研究 通过提供对细胞贩运的见解，对卵泡的研究将对该领域产生广泛的影响， 免疫治疗方法的持久性和预处理方案。最重要的是， 这些研究可能会产生一种有效的策略来诱导艾滋病毒的长期持续缓解。