Gene Therapy Program, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
Precision BioSciences, Durham, North Carolina, USA.
Nat Biotechnol. 2018 Sep;36(8):717-725. doi: 10.1038/nbt.4182. Epub 2018 Jul 9.
Clinical translation of in vivo genome editing to treat human genetic diseases requires thorough preclinical studies in relevant animal models to assess safety and efficacy. A promising approach to treat hypercholesterolemia is inactivating the secreted protein PCSK9, an antagonist of the LDL receptor. Here we show that single infusions in six non-human primates of adeno-associated virus vector expressing an engineered meganuclease targeting PCSK9 results in dose-dependent disruption of PCSK9 in liver, as well as a stable reduction in circulating PCSK9 and serum cholesterol. Animals experienced transient, asymptomatic elevations of serum transaminases owing to the formation of T cells against the transgene product. Vector DNA and meganuclease expression declined rapidly, leaving stable populations of genome-edited hepatocytes. A second-generation PCSK9-specific meganuclease showed reduced off-target cleavage. These studies demonstrate efficient, physiologically relevant in vivo editing in non-human primates, and highlight safety considerations for clinical translation.
临床将体内基因组编辑用于治疗人类遗传疾病需要在相关动物模型中进行彻底的临床前研究，以评估安全性和有效性。一种有前途的治疗高胆固醇血症的方法是使分泌型蛋白 PCSK9 失活，PCSK9 是 LDL 受体的拮抗剂。在这里，我们展示了在六种非人类灵长类动物中单次输注表达针对 PCSK9 的工程化 meganuclease 的腺相关病毒载体，导致肝中 PCSK9 呈剂量依赖性破坏，以及循环 PCSK9 和血清胆固醇的稳定降低。由于针对转基因产物形成 T 细胞，动物经历了短暂的、无症状的血清转氨酶升高。载体 DNA 和 meganuclease 表达迅速下降，留下稳定的基因组编辑肝细胞群体。第二代 PCSK9 特异性 meganuclease 显示出减少的脱靶切割。这些研究证明了在非人类灵长类动物中进行高效、生理相关的体内编辑，并强调了临床转化的安全性考虑因素。
