For inherited genetic diseases, fetal gene therapy offers the potential of prophylaxis against early, irreversible and lethal pathological change. To explore this, we studied neuronopathic Gaucher disease (nGD), caused by mutations in GBA. In adult patients, the milder form presents with hepatomegaly, splenomegaly and occasional lung and bone disease; this is managed, symptomatically, by enzyme replacement therapy. The acute childhood lethal form of nGD is untreatable since enzyme cannot cross the blood-brain barrier. Patients with nGD exhibit signs consistent with hindbrain neurodegeneration, including neck hyperextension, strabismus and, often, fatal apnea¹. We selected a mouse model of nGD carrying a loxP-flanked neomycin disruption of Gba plus Cre recombinase regulated by the keratinocyte-specific K14 promoter. Exclusive skin expression of Gba prevents fatal neonatal dehydration. Instead, mice develop fatal neurodegeneration within 15 days². Using this model, fetal intracranial injection of adeno-associated virus (AAV) vector reconstituted neuronal glucocerebrosidase expression. Mice lived for up to at least 18 weeks, were fertile and fully mobile. Neurodegeneration was abolished and neuroinflammation ameliorated. Neonatal intervention also rescued mice but less effectively. As the next step to clinical translation, we also demonstrated the feasibility of ultrasound-guided global AAV gene transfer to fetal macaque brains.

中文翻译：

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针对婴儿神经退行性疾病的胎儿基因治疗。


对于遗传性遗传疾病，胎儿基因治疗具有预防早期、不可逆和致命的病理变化的潜力。为了探索这一点，我们研究了由 GBA 突变引起的神经病性戈谢病 (nGD)。在成年患者中，较轻的形式表现为肝肿大、脾肿大，偶尔有肺和骨疾病；通过酶替代疗法对症治疗。由于酶无法穿过血脑屏障，因此儿童急性致死性 nGD 无法治疗。 nGD 患者表现出与后脑神经变性一致的体征，包括颈部过度伸展、斜视，以及通常致命的呼吸暂停¹ 。我们选择了 nGD 小鼠模型，该模型携带 loxP 侧翼新霉素破坏 Gba 以及由角质形成细胞特异性 K14 启动子调节的 Cre 重组酶。 Gba 的独特皮肤表达可防止致命的新生儿脱水。相反，小鼠会在 15 天内出现致命的神经变性² 。使用该模型，胎儿颅内注射腺相关病毒（AAV）载体重建神经元葡萄糖脑苷脂酶表达。小鼠的寿命至少长达 18 周，具有生育能力并且完全活动。神经变性被消除，神经炎症得到改善。新生儿干预也拯救了小鼠，但效果较差。作为临床转化的下一步，我们还证明了超声引导下将 AAV 基因转移至胎儿猕猴大脑的可行性。