Department of Neurological Surgery, University of California San Francisco, San Francisco, California, USA.
Department of Neurological Surgery, University of California San Francisco, San Francisco, California, USA; Current address: Department of Neurological Surgery, Laboratory for CNS Repair, Brain and Spinal Cord Injury Center, University of California San Francisco, San Francisco, California, USA.
Mol Ther. 2014 Feb;22(2):329-337. doi: 10.1038/mt.2013.266. Epub 2013 Nov 21.
Many studies have demonstrated that adeno-associated virus serotype 9 (AAV9) transduces astrocytes and neurons when infused into rat or nonhuman primate (NHP) brain. We previously showed in rats that transduction of antigen-presenting cells (APC) by AAV9 encoding a foreign protein triggered a full neurotoxic immune response. Accordingly, we asked whether this phenomenon occurred in NHP. We performed parenchymal or intrathecal infusion of AAV9 encoding green fluorescent protein (GFP), a non-self protein derived from jellyfish, or human aromatic L-amino acid decarboxylase (hAADC), a self-protein, in separate NHP. Animals receiving AAV9-GFP into cisterna magna (CM) became ataxic, indicating cerebellar pathology, whereas AAV9-hAADC animals remained healthy. In transduced regions, AAV9-GFP elicited inflammation associated with early activation of astrocytic and microglial cells, along with upregulation of major histocompatibility complex class II (MHC-II) in glia. In addition, we found Purkinje neurons lacking calbindin after AAV9-GFP but not after AAV9-hAADC delivery. Our results demonstrate that AAV9-mediated expression of a foreign-protein, but not self-recognized protein, triggers complete immune responses in NHP regardless of the route of administration. Our results warrant caution when contemplating use of serotypes that can transduce APC if the transgene is not syngeneic with the host. This finding has the potential to complicate preclinical toxicology studies in which such vectors encoding human cDNA's are tested in animals.
许多研究表明，腺相关病毒血清型 9（AAV9）在注入大鼠或非人灵长类动物（NHP）大脑时可转导星形胶质细胞和神经元。我们之前在大鼠中表明，AAV9 转导抗原呈递细胞（APC）所编码的外来蛋白会引发全面的神经毒性免疫反应。因此，我们询问这种现象是否会在 NHP 中发生。我们在 NHP 中进行了实质内或鞘内注射编码绿色荧光蛋白（GFP）的 AAV9，GFP 是一种源自水母的非自身蛋白，或编码人类芳香族 L-氨基酸脱羧酶（hAADC）的 AAV9，hAADC 是一种自身蛋白。将 AAV9-GFP 注入小脑延髓池（CM）的动物出现共济失调，表明小脑病理学，而接受 AAV9-hAADC 的动物则保持健康。在转导区域，AAV9-GFP 引发了与星形胶质细胞和小胶质细胞早期激活相关的炎症，以及神经胶质细胞中主要组织相容性复合体 II（MHC-II）的上调。此外，我们发现 AAV9-GFP 递送后 Purkinje 神经元缺乏 calbindin，但 AAV9-hAADC 递送后则没有。我们的研究结果表明，AAV9 介导的外源蛋白表达，而不是自身识别蛋白的表达，会在 NHP 中引发完整的免疫反应，无论给药途径如何。如果转基因与宿主不同源，那么在考虑使用可以转导 APC 的血清型时，我们需要谨慎。这一发现有可能使编码人类 cDNA 的此类载体在动物中进行的临床前毒理学研究变得复杂。
