PDF(Pubmed)
Abstract：
Alpha-1 antitrypsin deficiency (AATD) is characterized by both chronic lung disease due to loss of wild-type AAT (M-AAT) antiprotease function and liver disease due to toxicity from delayed secretion, polymerization, and aggregation of misfolded mutant AAT (Z-AAT). The ideal gene therapy for AATD should therefore comprise both endogenous Z-AAT suppression and M-AAT overexpression. We designed a dual-function rAAV3B (df-rAAV3B) construct, which was effective at transducing hepatocytes, resulting in a considerable decrease of Z-AAT levels and safe M-AAT augmentation in mice. We optimized df-rAAV3B and created two variants, AAV3B-E12 and AAV3B-G3, to simultaneously enhance the concentration of M-AAT in the bloodstream to therapeutic levels and silence endogenous AAT liver expression in cynomolgus monkeys. Our results demonstrate that AAV3b-WT, AAV3B-E12, and AAV3B-G3 were able to transduce the monkey livers and achieve high M-AAT serum levels efficiently and safely. In this nondeficient model, we did not find downregulation of endogenous AAT. However, the dual-function vector did serve as a potentially \"liver-sparing\" alternative for high-dose liver-mediated AAT gene replacement in the context of underlying liver disease.
摘要：
α-1抗胰蛋白酶缺乏症（AATD）的特征是由于野生型AAT（M-AAT）抗蛋白酶功能丧失而导致的慢性肺病和由于分泌延迟引起的毒性而导致的肝病，聚合，和错误折叠突变体AAT(Z-AAT)的聚集。因此,AATD的理想基因治疗应包括内源性Z-AAT抑制和M-AAT过表达。我们设计了一种双功能rAAV3B(df-rAAV3B)结构，这在转导肝细胞方面是有效的，导致小鼠中Z-AAT水平的显著降低和安全的M-AAT增强。我们优化了df-rAAV3B并创建了两个变体，AAV3B-E12和AAV3B-G3，同时将血液中M-AAT的浓度提高到治疗水平，并沉默食蟹猴内源性AAT肝脏表达。我们的结果表明AAV3b-WT，AAV3B-E12和AAV3B-G3能够转导猴肝脏并有效且安全地实现高M-AAT血清水平。在这个无缺陷的模型中，我们没有发现内源性AAT的下调。然而,在基础肝病的情况下,双功能载体确实可作为大剂量肝脏介导的AAT基因替代的潜在“保肝”替代方案.
