Development of a treatment for durable remission of HIV using transposon engineered CAR-T and NK cells

项目摘要 MarPam Pharma的目标是开发一种一次性治疗方法，以实现人类持久缓解 免疫缺陷病毒(HIV)感染后，患者将不再需要接受抗逆转录病毒治疗。我们的 治疗是一种自体HIV特异性嵌合抗原受体(CAR)免疫细胞疗法，它使用 CXCR5趋化因子受体作为归巢装置引导抗HIV T细胞或抗HIV自然杀伤细胞(NK) 在淋巴B细胞滤泡中，大多数产生病毒的细胞被免疫保护的“隐藏”病毒库 位于慢性感染期间。病毒特异性CD8 T细胞对HIV-1具有强大的抗病毒活性 猴免疫缺陷病毒(SIV)，HIV的一种动物模型。然而，尽管CD8 T细胞丰富 HIV-1感染者和SIV感染猕猴的反应，这些细胞不能完全抑制病毒 复制，可能是因为大多数HIV-1和SIV复制发生在集中在 次级淋巴组织中的B细胞滤泡，感染的患者中驻留的病毒特异性CD8T细胞令人惊讶地少 个人。事实上，我们发现体内靶向病毒(V)RNA细胞(E：T)的体内效应器CTL水平降低了40倍 与B细胞滤泡外相比，可能是因为很少有病毒特异性CD8T细胞表达 卵泡归巢分子CXCR5。这些发现表明，HIV特异性CD8 T细胞无法 完全抑制病毒复制可能是由于B细胞滤泡缺乏病毒特异性CD8T细胞所致。作为 绝大多数病毒产生细胞是位于次级淋巴组织中的CD4T细胞，并集中在 在慢性HIV和SIV感染期间的卵泡，我们通过注入自体抗病毒药物来靶向这些感染细胞 慢性SIV感染猕猴体内的CAR/CXCR5-T细胞经过治疗的动物显示出了成功 CAR/CXCR5-T细胞归巢到B细胞滤泡，证明CAR/CXCR5-T细胞与 与未经处理的动物相比，vRNA感染了细胞并降低了病毒载量。我们的飞行员 研究表明，该疗法安全有效。这些发现促使我们进一步完善 我们有希望通过提高CAR/CXCR5-T细胞的疗效来进行靶向治疗，并研究这是否 靶向免疫细胞疗法可以利用NK细胞来开发。CAR-T和CAR-NK细胞疗法 个体化疗法通过改变患者自身的免疫细胞来对抗疾病；NK细胞疗法也有 使用同种异体细胞作为现成治疗方法的潜力。这项建议旨在优化 我们的CAR/CXCR5免疫细胞疗法的有效性。此外，我们的目标是生成和评估优化的 CAR/CXCR5-T和-NK细胞使用成本较低的生产方法。圆满完成拟议中的 研究将导致第二阶段的IND-使灵长类动物研究，以评估T细胞和NK的安全性和有效性 持久缓解艾滋病毒的细胞疗法。

Project Summary MarPam Pharma aims to develop a one-time treatment for achieving durable remission of human immunodeficiency virus (HIV), after which patients will no longer need to take antiretroviral therapy. Our treatment is an autologous HIV-specific chimeric antigen receptor (CAR) immune cell therapy that employs the CXCR5 chemokine receptor as a homing device to direct either anti-HIV T cells or anti-HIV natural killer (NK) cells into immune-protected “hidden” viral reservoirs in lymphoid B cell follicles, where most virus-producing cells are located during chronic infection. Virus-specific CD8 T cells exert potent antiviral activity against HIV-1 and Simian immunodeficiency virus (SIV), an animal model of HIV. Nevertheless, despite abundant CD8 T cell responses in HIV-1-infected humans and SIV-infected macaques, these cells do not fully suppress virus replication, likely because the majority of HIV-1 and SIV replication occurs in CD4+ T cells concentrated within B cell follicles in secondary lymphoid tissues, where surprisingly few virus-specific CD8 T cells reside in infected individuals. In fact, we found 40-fold lower levels of in vivo effector CTL to target viral (v)RNA+ cells (E:T) inside compared to outside of B cell follicles, likely explained by the fact that very few virus-specific CD8 T cells express the follicular homing molecule CXCR5. These findings suggest that the inability of HIV-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. As the vast majority of virus-producing cells are CD4 T cells located in secondary lymphoid tissue and concentrated in follicles during chronic HIV and SIV infections, we targeted these infected cells by infusing autologous antiviral CAR/CXCR5-T cells in chronically SIV-infected rhesus macaques. The treated animals showed successful homing of CAR/CXCR5-T cells to B cell follicles, evidence of direct contact of the CAR/CXCR5-T cells with vRNA+ infected cells and decreased viral loads in treated animals compared to untreated animals. Our pilot study showed that the treatment was safe and effective. These findings have prompted us to further refine our promising targeted CAR/CXCR5-T cell therapy by enhancing its efficacy and to investigate whether this targeted immune cell therapy could be developed using NK cells. CAR-T and CAR-NK cell therapies are individualized therapies that modify a patient’s own immune cells to fight disease; NK cell therapies also have the potential to function as off-the-shelf treatments using allogenic cells. This proposal seeks to optimize the effectiveness of our CAR/CXCR5 immune cell therapy. In addition, we aim to generate and evaluate optimized Car/CXCR5-T and -NK cells using less expensive production methods. Successful completion of the proposed studies will lead to Phase II IND-enabling primate studies to assess the safety and efficacy of the T cell and NK cell therapies for durable HIV remission.