Vance Melisa, Llanga Telmo, Bennett Will, Woodard Kenton, Murlidharan Giridhar, Chungfat Neil, Asokan Aravind, Gilger Brian, Kurtzberg Joanne, Samulski R Jude, Hirsch Matthew L
Gene Therapy Center, University of North Carolina at Chapel Hill, NC, 27599, USA.
Department of Ophthalmology, University of North Carolina, Chapel Hill, NC, 27599, USA.
Sci Rep. 2016 Feb 22;6:22131. doi: 10.1038/srep22131.
Although cord blood transplantation has significantly extended the lifespan of mucopolysaccharidosis type 1 (MPS1) patients, over 95% manifest cornea clouding with about 50% progressing to blindness. As corneal transplants are met with high rejection rates in MPS1 children, there remains no treatment to prevent blindness or restore vision in MPS1 children. Since MPS1 is caused by mutations in idua, which encodes alpha-L-iduronidase, a gene addition strategy to prevent, and potentially reverse, MPS1-associated corneal blindness was investigated. Initially, a codon optimized idua cDNA expression cassette (opt-IDUA) was validated for IDUA production and function following adeno-associated virus (AAV) vector transduction of MPS1 patient fibroblasts. Then, an AAV serotype evaluation in human cornea explants identified an AAV8 and 9 chimeric capsid (8G9) as most efficient for transduction. AAV8G9-opt-IDUA administered to human corneas via intrastromal injection demonstrated widespread transduction, which included cells that naturally produce IDUA, and resulted in a >10-fold supraphysiological increase in IDUA activity. No significant apoptosis related to AAV vectors or IDUA was observed under any conditions in both human corneas and MPS1 patient fibroblasts. The collective preclinical data demonstrate safe and efficient IDUA delivery to human corneas, which may prevent and potentially reverse MPS1-associated cornea blindness.
尽管脐血移植显著延长了黏多糖贮积症 I 型（MPS1）患者的寿命，但超过 95%的患者出现角膜混浊，约 50%的患者会发展为失明。由于 MPS1 患儿的角膜移植排斥率很高，目前仍然没有治疗方法来预防 MPS1 患儿失明或恢复视力。由于 MPS1 是由编码 α-L-艾杜糖醛酸酶的 idua 基因突变引起的，因此研究了一种基因添加策略来预防并可能逆转 MPS1 相关的角膜失明。最初，在 MPS1 患者成纤维细胞经腺相关病毒（AAV）载体转导后，对密码子优化的 idua cDNA 表达盒（opt-IDUA）进行了 IDUA 产生和功能验证。然后，在人角膜外植体中进行的 AAV 血清型评估确定 AAV8 和 9 嵌合衣壳（8G9）是转导效率最高的。通过基质内注射将 AAV8G9-opt-IDUA 施用于人角膜，显示出广泛的转导，包括天然产生 IDUA 的细胞，并导致 IDUA 活性超生理水平增加 10 倍以上。在人角膜和 MPS1 患者成纤维细胞的任何条件下，均未观察到与 AAV 载体或 IDUA 相关的明显细胞凋亡。这些临床前数据共同证明了将 IDUA 安全有效地递送至人角膜，这可能预防并潜在逆转 MPS1 相关的角膜失明。
