Gene Therapy Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Division of Genetics and Metabolism, Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Gene Ther. 2023 Apr;30(3-4):377-385. doi: 10.1038/s41434-022-00368-9. Epub 2022 Oct 17.
The widespread pre-existing αAAV-Abs in humans pose a critical challenge in translation of AAV gene therapy. The IgG degrading enzyme of Streptococci (IdeS) is demonstrated to specifically cleave IgG of humans and other species (not mouse). This study developed a modified new modified IdeS protein product (IdeS). When incubated in vitro, IdeS was shown to completely cleave human and rabbit IgGs within 6 h. To test IdeS in a disease setting, we established a rabbitized αAAV9-Ab mouse by an IV infusion of purified acute αAAV9-Ab rabbit IgG into MPS IIIA mice, resulting in serum αAAV9-IgG at 1:6,400 and αAAV9-nAbs at 1:800. IdeS-Ab-cleavage was shown to be dose-dependent. An IV IdeS infusion at the effective doses resulted in rapid IgG depletion and clearance of pre-existing αAAV9-IgG and αAAV9-nAbs in rabbitized αAAV9-Abs MPS IIIA mice. Importantly, an IV injection of a high dose AAV9-hSGSH vector (5 × 10vg/kg) at 24 h post IdeS treatment led to transduction as effective in αAAV9-Abs MPS IIIA mice, as in αAAV9-Abs-negative controls. We believe that transient IdeS administration may offer a great tool to address the pre-existing-αAAV-Abs for the translation of rAAV gene therapy to treat diseases in humans, making effective rAAV gene therapy available to all patients in need.
在人类中广泛存在的预先存在的αAAV-Abs 给 AAV 基因治疗的转化带来了巨大挑战。链球菌 IgG 降解酶（IdeS）已被证明能够特异性地切割人类和其他物种（非小鼠）的 IgG。本研究开发了一种改良的新型 IdeS 蛋白产物（IdeS）。体外孵育时，IdeS 在 6 小时内即可完全切割人源和兔源 IgG。为了在疾病模型中测试 IdeS，我们通过静脉输注纯化的急性αAAV9-Ab 兔 IgG 建立了兔源αAAV9-Ab 小鼠模型，导致血清中αAAV9-IgG 效价达到 1:6,400，αAAV9-中和抗体效价达到 1:800。结果表明 IdeS 的切割具有剂量依赖性。静脉输注有效剂量的 IdeS 可迅速耗尽预先存在的αAAV9-IgG 和αAAV9-中和抗体，并清除兔源αAAV9-Ab 小鼠中的αAAV9-Ab。重要的是，在 IdeS 处理后 24 小时静脉注射高剂量 AAV9-hSGSH 载体（5×10vg/kg），可在兔源αAAV9-Ab 小鼠中实现与αAAV9-Ab 阴性对照一样有效的转导。我们认为，短暂的 IdeS 给药可能为解决预先存在的αAAV-Abs 提供了一种重要工具，有助于将 rAAV 基因治疗转化为治疗人类疾病，使所有有需要的患者都能获得有效的 rAAV 基因治疗。
