Improved Nanoparticle Targeting of Tissue Myeloid Cells for HIV-1 Long-acting Pre-exposure Prophylaxis

总结 抗逆转录病毒暴露前预防（PrEP）是预防向病毒初治者传播的重要工具。 艾滋病毒感染者是艾滋病患者，在目前结束艾滋病毒流行的努力中发挥着重要作用。如果每天服用当前口服PrEP 这些战略可靠地阻断了艾滋病毒的传播。然而，严格遵守每日服药的要求， 疲劳和其他机构障碍使口服PrEP未得到充分利用。长效注射PrEP 这些策略有可能解决与口服PrEP相关的许多问题，但 确保药物持续释放至少三个月的药物制剂和递送策略， 仍然具有挑战性，并推动了全新的长效PrEP策略的发展。这个项目 开发了一种基于膜包裹纳米颗粒（NPs）的长效注射PrEP策略， 用于在原代组织持续维持抗逆转录病毒药物（ARV）抑制浓度的细胞库 女性生殖道和直肠中的HIV-1传播部位。选择性靶向表达CD 169的 巨噬细胞和树突状细胞的融合是通过在NP中掺入神经节苷脂GM 3来实现的。 膜的GM 3-CD 169结合触发非内溶酶体区室中NP的摄取和隔离 与组织相关巨噬细胞中的含病毒区室（VCC）有明显的相似性， 树突状细胞这些区室代表了受保护的位点，NP可以从这些位点将药物释放到细胞中。 周围组织长时间。嵌段共聚物的膜包裹的反胶束将 长效替诺福韦（TFV）和 恩曲他滨（FTC）前药将用作活性化合物以验证该方法。嵌段共聚物 NP将含有共价连接至聚合物壳的TFV，该聚合物壳包封保持FTC的水性核 与树枝状聚合物缀合。在体外定量载药量和释放后，GM 3介导的靶向作用被证实是有效的。 将测试人源化小鼠模型的FGT和直肠中的CD 169+骨髓细胞。与此同时，GM 3- NP平台将被优化以实现在靶组织中的持续药物释放。的假设 优化的NP在人源化小鼠模型中提供了至少三种针对粘膜HIV感染的保护， 几个月将受到考验。本申请的具体目的是： 目的1：开发用于TFV/FTC缓释的膜包裹多组分纳米粒。 目的2：靶向FGT和SLT中表达CD 169的髓样细胞，以持续释放TFV/FTC。 目的3：证明TFV/FTC在人源化小鼠中对粘膜HIV-1传播的长期保护作用 掺入GM 3-NP。

Summary Antiretroviral pre-exposure prophylaxis (PrEP) is an important tool for preventing transmission to virus naïve individuals and plays an important role in current efforts to end the HIV epidemic. If taken daily current oral PrEP strategies reliably block HIV transmission. However, the requirement of strict adherence to daily pill uptake, pill fatigue and other institutional barriers to access leave oral PrEP underutilized. Long-acting injectable PrEP strategies have the potential to address many of the problems associated with oral PrEP but the realization of drug formulations and delivery strategies that ensure sustained drug release for at least three months has remained challenging and motivates the development of entirely new long-acting PrEP strategies. This project develops a long-acting injectable PrEP strategy based on membrane-wrapped nanoparticles (NPs) that establish cellular depots for sustained maintenance of inhibitory concentrations of antiretrovirals (ARVs) at primary tissue sites of HIV-1 transmission in the female genital tract (FGT) and rectum. Selective targeting of CD169-expressing macrophages and dendritic cells is accomplished through incorporation of the ganglioside GM3 in the NP membrane. GM3-CD169 binding triggers uptake and sequestration of NPs in non-endolysosomal compartments that share distinct similarities with virus containing compartments (VCCs) in tissue-associated macrophages and dendritic cells. These compartments represent protected sites from where NPs can release drugs into the surrounding tissue for an extended period of time. Membrane-wrapped inverse micelles of block copolymers will be engineered as a GM3-NP platform for long-acting PrEP. A combination of long-acting tenofovir (TFV) and emtricitabine (FTC) prodrugs will be used as active compounds to validate the approach. The block copolymer NPs will contain TFV covalently linked to a polymer shell that encapsulates an aqueous core holding FTC conjugated to dendrimers. After quantifying drug loading and release in vitro, the GM3-mediated targeting of CD169+ myeloid cells in the FGT and rectum of a humanized mouse model will be tested. In parallel, the GM3- NP platform will be optimized to achieve sustained drug release in the target tissues. The hypothesis that the optimized NPs provide protection from mucosal HIV infection in a humanized mouse model for at least three months will be tested. The specific aims of this application are: Aim 1: To develop membrane-wrapped multicomponent NPs for sustained release of TFV/FTC. Aim 2: To target CD169-expressing myeloid cells in the FGT and SLTs for sustained TFV/FTC release. Aim 3: To demonstrate long-term protection from mucosal HIV-1 transmission in humanized mice by TFV/FTC incorporating GM3-NPs.