San Raffaele Telethon Institute for Gene Therapy, IRCCS San Raffaele Scientific Institute, Milan, Italy.
Vita-Salute San Raffaele University, Milan, Italy.
Nat Commun. 2022 May 4;13(1):2454. doi: 10.1038/s41467-022-30102-3.
Liver gene therapy with adeno-associated viral (AAV) vectors delivering clotting factor transgenes into hepatocytes has shown multiyear therapeutic benefit in adults with hemophilia. However, the mostly episomal nature of AAV vectors challenges their application to young pediatric patients. We developed lentiviral vectors, which integrate in the host cell genome, that achieve efficient liver gene transfer in mice, dogs and non-human primates, by intravenous delivery. Here we first compare engineered coagulation factor VIII transgenes and show that codon-usage optimization improved expression 10-20-fold in hemophilia A mice and that inclusion of an unstructured XTEN peptide, known to increase the half-life of the payload protein, provided an additional >10-fold increase in overall factor VIII output in mice and non-human primates. Stable nearly life-long normal and above-normal factor VIII activity was achieved in hemophilia A mouse models. Overall, we show long-term factor VIII activity and restoration of hemostasis, by lentiviral gene therapy to hemophilia A mice and normal-range factor VIII activity in non-human primate, paving the way for potential clinical application.
腺相关病毒（AAV）载体将凝血因子转基因递送到肝细胞中的肝脏基因治疗已在成年血友病患者中显示出多年的治疗益处。然而，AAV 载体的主要附加体性质挑战了它们在年轻儿科患者中的应用。我们开发了慢病毒载体，通过静脉内递送，在小鼠、狗和非人类灵长类动物中实现了有效的肝脏基因转移。在这里，我们首先比较了工程凝血因子 VIII 转基因，并表明密码子使用优化使血友病 A 小鼠中的表达提高了 10-20 倍，并且包含已知可增加有效载荷蛋白半衰期的无结构 XTEN 肽，在小鼠和非人类灵长类动物中提供了另外的 >10 倍的总体因子 VIII 输出增加。在血友病 A 小鼠模型中，稳定的几乎终生正常和高于正常的因子 VIII 活性得以实现。总的来说，我们通过慢病毒基因治疗展示了血友病 A 小鼠的长期因子 VIII 活性和止血功能的恢复，以及非人类灵长类动物的正常范围因子 VIII 活性，为潜在的临床应用铺平了道路。
