AAV liver expression of FIX-Padua prevents and eradicates FIX inhibitor without increasing thrombogenicity in hemophilia B dogs and mice
AAV liver expression of FIX-Padua prevents and eradicates FIX inhibitor without increasing thrombogenicity in hemophilia B dogs and mice
复制标题
DOI：
10.1182/blood-2014-07-588194
复制
发表时间：
2015-03-05
期刊：
影响因子：
20.3
通讯作者：
Arruda, Valder R.
中科院分区：
文献类型：
--
作者：
Crudele, Julie M.;Finn, Jonathan D.;Arruda, Valder R.
使用腺相关病毒（AAV）载体进行血友病B（HB）基因治疗的成功临床数据显示，对载体衣壳的细胞免疫应答风险明显依赖于剂量。为了降低载体剂量，我们在FIX受体易感性HB犬中探索了编码高功能因子IX（FIX-帕多瓦，精氨酸338至亮氨酸）的AAV-8（1-3 x 10（12）vg/kg）。两只幼稚HB犬显示FIX-帕多瓦的持续表达，比活性增加8至12倍，达到25%至40%的活性，而不形成FIX抗体。第三只预先存在FIX抑制剂的犬在载体给药后2周表现出一过性记忆应答（5 Bethesda单位），随后在第70天自发根除FIX抗体。在该犬中，FIX持续表达分别达到活性和抗原水平的200%和30%。用血浆源性FIX浓缩物攻毒后，在所有犬中证实了免疫耐受性。凝血时间的缩短和出血事件的缺乏支持重度表型的表型校正，没有血栓形成风险的临床或实验室证据。在小鼠中进行的激发性研究表明，FIX-Padua与FIX野生型相比具有相似的免疫原性和血栓形成性。总的来说，这些数据支持潜在的翻译基因为基础的战略，使用FIX帕多瓦HB。
Emerging successful clinical data on gene therapy using adeno-associated viral (AAV) vector for hemophilia B (HB) showed that the risk of cellular immune response to vector capsid is clearly dose dependent. To decrease the vector dose, we explored AAV-8 (1-3 x 10(12) vg/kg) encoding a hyperfunctional factor IX (FIX-Padua, arginine 338 to leucine) in FIX inhibitor-prone HB dogs. Two naive HB dogs showed sustained expression of FIX-Padua with an 8- to 12-fold increased specific activity reaching 25% to 40% activity without antibody formation to FIX. A third dog with preexisting FIX inhibitors exhibited a transient anamnestic response (5 Bethesda units) at 2 weeks after vector delivery following by spontaneous eradication of the antibody to FIX by day 70. In this dog, sustained FIX expression reached similar to 200% and 30% of activity and antigen levels, respectively. Immune tolerance was confirmed in all dogs after challenges with plasma-derived FIX concentrate. Shortening of the clotting times and lack of bleeding episodes support the phenotypic correction of the severe phenotype, with no clinical or laboratory evidence of risk of thrombosis. Provocative studies in mice showed that FIX-Padua exhibits similar immunogenicity and thrombogenicity compared with FIX wild type. Collectively, these data support the potential translation of gene-based strategies using FIX-Padua for HB.