Abstract：
Nosebleeds and intracranial hemorrhage from brain arteriovenous malformations (bAVMs) are among the most devastating symptoms of patients with hereditary hemorrhagic telangiectasis (HHT). All available managements have limitations. We showed that intravenous (i.v.) delivery of soluble Feline McDonough Sarcoma (FMS)-related tyrosine kinase 1 using an adeno-associated viral vector (AAV9-sFLT1) reduced bAVM severity of endoglin deficient mice. However, minor liver inflammation and growth arrest in young mice were observed. To identify AAV variants and delivery methods that can best transduce brain and nasal tissue with an optimal transduction profile, we compared 3 engineered AAV capsids (AAV.cc47, AAV.cc84, and AAV1RX) with AAV9. A single-stranded CBA promoter driven tdTomato transgene was packaged in these capsids and delivered i.v. or intranasally (i.n.) to wild-type mice. A CMV promoter driven Alk1 transgene was packaged into AAV.cc84 and delivered to PdgfbiCre;Alk1f/f mice through i.v. followed by bAVM induction. Transduced cells in organs, vessel density, abnormal vessels in the bAVMs, and liver inflammation were analyzed histologically. Liver and kidney function were measured enzymatically. Compared to other viral vectors, AAV.cc84, after i.v. delivery, transduced a high percentage of brain endothelial cells (ECs) and few hepatocytes; whereas after i.n. delivery, AAV.cc84 transduced ECs and perivascular cells in the brain, and ECs, epithelial cells, and muscles in the nose with minimum hepatocyte transduction. No changes to liver or kidney function were detected. The delivery of AAV.cc84-Alk1 through i.v. to PdgfbiCre;Alk1f/f mice reduced bAVM severity. In summary, we propose that AAV.cc84-Alk1 is a promising candidate for developing gene therapy in HHT patients.
摘要：
脑动静脉畸形（bAVM）引起的流鼻血和颅内出血是遗传性出血性毛细血管扩张（HHT）患者最具破坏性的症状。所有可用的管理都有局限性。我们表明，使用腺相关病毒载体（AAV9-sFLT1）静脉内（i.v.）递送可溶性猫麦克唐纳肉瘤（FMS）相关的酪氨酸激酶1可降低内皮糖蛋白缺陷小鼠的bAVM严重程度。然而,观察到幼鼠肝脏轻微炎症和生长停滞。为了确定能够以最佳转导曲线最佳转导脑和鼻组织的AAV变体和递送方法，我们比较了3个工程化AAV衣壳(AAV。cc47，AAV。cc84和AAV1RX）与AAV9。将单链CBA启动子驱动的tdTomato转基因包装在这些衣壳中并经静脉内或鼻内(i.n.)递送至野生型小鼠。将CMV启动子驱动的Alk1转基因包装到AAV中。cc84并通过静脉内递送至PdgfbiCre;Alk1f/f小鼠,随后进行bAVM诱导。器官中的转导细胞，血管密度,BAVM中的异常血管，对肝脏炎症进行组织学分析。酶促测量肝肾功能。与其他病毒载体相比，AAV。cc84，静脉注射后，转导高百分比的脑内皮细胞(ECs)和少数肝细胞;而在静脉注射后,AAV。CC84在大脑中转导ECs和血管周围细胞，和EC,上皮细胞，和鼻子中的肌肉，肝细胞转导最少。未检测到肝或肾功能的变化。AAV的交付。cc84-Alk1通过静脉给PdgfbiCre；Alk1f/f小鼠降低了bAVM的严重程度。总之,我们提议AAV。cc84-Alk1是开发HHT患者基因治疗的有希望的候选者。
