TARGETED siRNA DELIVERY AS AN ANTI-HIV MICROBICIDE

描述（由申请人提供）：人类免疫缺陷病毒（HIV）是一种高致死性慢病毒，在长期过程中破坏宿主的适应性免疫系统，使其容易受到许多机会性感染。与大多数病毒的基因组独立于宿主细胞的基因组复制不同，HIV-1基因组整合到宿主遗传物质中并与宿主遗传物质一起复制。因此，即使治疗方法可以抑制新病毒的产生，病毒基因组仍然保持完整和有能力。因此，可以防止病毒摄取和整合的策略将具有巨大的临床价值。绝大多数HIV感染是由于病毒通过粘膜表面（如阴道粘膜）传播而发生的。将特异性沉默HIV生命周期早期事件所需的宿主因子的siRNA递送到阴道粘膜中的淋巴细胞，可以证明是保护个体免受HIV感染的有效手段，并作为潜在的杀微生物剂。siRNA作为遗传疗法的临床应用所面临的主要挑战之一是将siRNA递送至适当靶细胞类型的细胞质的能力。我们最近开发了一种新的脂质纳米颗粒，其涂覆有识别在淋巴细胞上广泛表达的整合素分子LFA-1的抗体。这些免疫纳米颗粒将用于将siRNA递送到HIV的人源化小鼠模型的阴道粘膜中存在的淋巴细胞。鉴于高水平的序列异质性、HIV-1突变的倾向以及抗HIV siRNA不能靶向进入的病毒RNA基因组并阻止整合，需要替代的治疗靶标来防止HIV的传播。对于HIV生命周期中的早期事件是必要的，但对于细胞功能是不必要的宿主因素可能被证明是一种有效的治疗选择。使用基于高通量RNA干扰的筛选平台，我们已经确定了大量潜在的治疗靶点，这些靶点在沉默时可以抑制HIV整合。然而，这些因素需要广泛的分析和表征，以确保其安全性和有效性。我们将结合LFA-1介导的细胞类型特异性载体，引入靶向治疗相关宿主因子的siRNA，作为抑制HIV人源化小鼠模型中病毒感染的潜在手段。这些实验将为开发有效的基于RNAi的抗HIV杀微生物剂提供必要的临床前基础。异性性传播是世界上新的艾滋病毒感染的主要原因。提供真正的细胞内免疫的杀微生物剂将对控制这种致命病毒的传播做出重大贡献。

DESCRIPTION (provided by applicant): Human immunodeficiency virus (HIV) is a highly lethal lentivirus which over a protracted course destroys the host's adaptive immune system leaving them vulnerable to numerous opportunistic infections. Unlike most viruses whose genome replicates independently of the host cell's genome, the HIV-1 genome integrates into and is replicated with the host genetic material. Therefore, even if therapeutic approaches can inhibit new virus production, the viral genome remains intact and competent. Therefore, strategies that can prevent the uptake and integration of the virus would be of tremendous clinical value. The vast majority of HIV infections occur as a consequence of viral transmission through mucosal surfaces, such as the vaginal mucosa. The delivery of siRNAs that specifically silence host factors required for early events in the HIV life cycle to lymphocytes in the vaginal mucosa could prove to be an effective means of protecting individuals from HIV infection and serve as a potential microbicide. One of the main challenges facing the clinical application of siRNAs as a genetic therapy is the ability to delivery siRNAs to the cytoplasm of the appropriate target cell types. We have recently developed a novel lipid nanoparticle that is coated with an antibody recognizing the integrin molecule LFA-1 which is broadly expressed on lymphocytes. These immuno-nanoparticles will be used to deliver siRNAs to lymphocytes present in the vaginal mucosa of humanized mouse models of HIV. Given the high level of sequence heterogeneity, the propensity of HIV-1 to mutate and the inability of anti-HIV siRNAs to target the incoming viral RNA genome and prevent integration, alternative therapeutic targets are required to prevent the transmission of HIV. Host factors that are necessary for early events in the HIV lifecycle but are dispensable for cellular functioning could prove to be an effective therapeutic alternative. Using a high-throughput RNA interference-based screening platform, we have identified a large number of potential therapeutic targets that could serve to inhibit HIV integration when silenced. However, these factors require extensive analysis and characterization to ensure their safety and efficacy. We will be combining the LFA-1-mediated cell-type specific vehicle to introduce siRNAs targeting therapeutically relevant host factors as a potential means to inhibit viral infection in humanized mouse models of HIV. These experiments will provide the preclinical groundwork necessary for the development of an effective RNAi-based anti-HIV microbicide. Heterosexual transmission is the leading cause of new HIV infections in the world. A microbicide providing true intracellular immunity would make a significant contribution to controlling the spread of this deadly virus.