Hawley Zachary C E, Pardo Ingrid D, Cao Shaolong, Zavodszky Maria I, Casey Fergal, Ferber Kyle, Luo Yi, Hana Sam, Chen Shukkwan K, Doherty Jessica, Costa Raquel, Cullen Patrick, Liu Yuqing, Carlile Thomas M, Chowdhury Twinkle, Doyle Benjamin, Clarner Pete, Mangaudis Kevin, Guilmette Edward, Bourque Shawn, Koske David, Nadella Murali V P, Trapa Patrick, Hawes Michael L, Raitcheva Denitza, Lo Shih-Ching
Biogen, Cambridge, MA, USA.
Charter Preclinical Services, Hudson, MA, USA.
Mol Ther. 2025 Jan 8;33(1):215-234. doi: 10.1016/j.ymthe.2024.11.029. Epub 2024 Nov 19.
Dorsal root ganglion (DRG) toxicity has been consistently reported as a potential safety concern after delivery of adeno-associated viruses (AAVs) containing gene-replacement vectors but has yet to be reported for RNAi-based vectors. Here, we report DRG toxicity after AAV intra-CSF delivery of an RNAi expression construct-artificial microRNA targeting superoxide dismutase 1 (SOD1)-in non-human primates (NHPs) and provide evidence that this can be recapitulated within mice. Histopathology evaluation showed that NHPs and mice develop DRG toxicity after AAV delivery, including DRG neuron degeneration and necrosis and nerve-fiber degeneration that were associated with increases in cerebrospinal fluid (CSF) and serum phosphorylated neurofilament heavy chain (pNF-H). RNA-sequencing analysis of DRGs showed that dysregulated pathways were preserved between NHPs and mice, including increases in innate/adaptive immune responses and decreases in mitochondrial- and neuronal-related genes, following AAV treatment. Finally, endogenous miR-21-5p was upregulated in DRGs of AAV-treated NHPs and mice. Increases in miR-21-5p were also identified within the CSF of NHPs, which significantly correlated with pNF-H, implicating miR-21-5p as a potential biomarker of DRG toxicity in conjunction with other molecular analytes. This work highlights the importance of assessing safety concerns related to DRG toxicity when developing RNAi-based AAV vectors for therapeutic purposes.
背根神经节（DRG）毒性一直被报道为在递送含基因替代载体的腺相关病毒（AAV）后一个潜在的安全问题，但基于RNA干扰（RNAi）的载体尚未有相关报道。在此，我们报告了在非人灵长类动物（NHP）中经脑脊液（CSF）内递送一种RNAi表达构建体——靶向超氧化物歧化酶1（SOD1）的人工微小RNA后出现的DRG毒性，并提供证据表明这在小鼠中也可重现。组织病理学评估显示，AAV递送后NHP和小鼠均出现DRG毒性，包括DRG神经元变性和坏死以及神经纤维变性，这些与脑脊液（CSF）和血清中磷酸化神经丝重链（pNF-H）增加有关。DRG的RNA测序分析表明，NHP和小鼠之间失调的通路是一致的，包括AAV处理后固有/适应性免疫反应增加以及线粒体和神经元相关基因减少。最后，在接受AAV处理的NHP和小鼠的DRG中内源性miR-21-5p上调。在NHP的CSF中也发现miR-21-5p增加，且与pNF-H显著相关，这表明miR-21-5p与其他分子分析物一起可能是DRG毒性的潜在生物标志物。这项工作凸显了在开发用于治疗目的的基于RNAi的AAV载体时评估与DRG毒性相关安全问题的重要性。
