Abstract：
Antisense oligonucleotides (ASOs) are promising therapeutics for treating various neurological disorders. However, ASOs are unable to readily cross the mammalian blood-brain barrier (BBB) and therefore need to be delivered intrathecally to the central nervous system (CNS). Here, we engineered a human transferrin receptor 1 (TfR1) binding molecule, the oligonucleotide transport vehicle (OTV), to transport a tool ASO across the BBB in human TfR knockin (TfRmu/hu KI) mice and nonhuman primates. Intravenous injection and systemic delivery of OTV to TfRmu/hu KI mice resulted in sustained knockdown of the ASO target RNA, Malat1, across multiple mouse CNS regions and cell types, including endothelial cells, neurons, astrocytes, microglia, and oligodendrocytes. In addition, systemic delivery of OTV enabled Malat1 RNA knockdown in mouse quadriceps and cardiac muscles, which are difficult to target with oligonucleotides alone. Systemically delivered OTV enabled a more uniform ASO biodistribution profile in the CNS of TfRmu/hu KI mice and greater knockdown of Malat1 RNA compared with a bivalent, high-affinity TfR antibody. In cynomolgus macaques, an OTV directed against MALAT1 displayed robust ASO delivery to the primate CNS and enabled more uniform biodistribution and RNA target knockdown compared with intrathecal dosing of the same unconjugated ASO. Our data support systemically delivered OTV as a potential platform for delivering therapeutic ASOs across the BBB.
摘要：
反义寡核苷酸(ASO)是用于治疗各种神经障碍的有前途的治疗剂。然而,ASO不能容易地穿过哺乳动物血脑屏障(BBB),因此需要鞘内递送至中枢神经系统(CNS)。这里,我们设计了一个人转铁蛋白受体1（TfR1）结合分子，寡核苷酸转运载体(OTV)，在人类TfR敲入（TfRmu/huKI）小鼠和非人灵长类动物中运输工具ASO穿过BBB。TfRmu/huKI小鼠静脉内注射和全身递送OTV导致ASO靶RNA的持续敲低，Malat1，跨多个小鼠CNS区域和细胞类型，包括内皮细胞,神经元，星形胶质细胞,小胶质细胞,和少突胶质细胞。此外,OTV的全身递送使Malat1RNA在小鼠股四头肌和心肌中击倒，它们很难单独用寡核苷酸靶向。与二价相比，系统递送的OTV在TfRmu/huKI小鼠的CNS中实现了更均匀的ASO生物分布谱，并且对Malat1RNA的敲减更大，高亲和力TfR抗体。在猕猴中，与相同的未结合ASO的鞘内给药相比，针对MALAT1的OTV显示出稳健的ASO向灵长类动物CNS的递送，并且能够实现更均匀的生物分布和RNA靶标敲低。我们的数据支持系统提供OTV，作为跨BBB提供治疗性ASO的潜在平台。
