Li Zhenyu, Ding Guangqian, Wang Yudi, Zheng Zelong, Lv Jianping
Department of Neurosurgery, Guangzhou First People's Hospital, School of Medicine, South China University of Technology, Guangzhou, Guangdong 510180, China.
Transl Neurosci. 2020 Jul 15;11(1):241-250. doi: 10.1515/tnsci-2020-0132. eCollection 2020.
Transcription factor EB (TFEB)-based gene therapy is a promising therapeutic strategy in treating neurodegenerative diseases by promoting autophagy/lysosome-mediated degradation and clearance of misfolded proteins that contribute to the pathogenesis of these diseases. However, recent findings have shown that TFEB has proinflammatory properties, raising the safety concerns about its clinical application. To investigate whether TFEB induces significant inflammatory responses in the brain, male C57BL/6 mice were injected with phosphate-buffered saline (PBS), adeno-associated virus serotype 8 (AAV8) vectors overexpressing mouse TFEB (pAAV8-CMV-mTFEB), or AAV8 vectors expressing green fluorescent proteins (GFPs) in the barrel cortex. The brain tissue samples were collected at 2 months after injection. Western blotting and immunofluorescence staining showed that mTFEB protein levels were significantly increased in the brain tissue samples of mice injected with mTFEB-overexpressing vectors compared with those injected with PBS or GFP-overexpressing vectors. pAAV8-CMV-mTFEB injection resulted in significant elevations in the mRNA and protein levels of lysosomal biogenesis indicators in the brain tissue samples. No significant changes were observed in the expressions of GFAP, Iba1, and proinflammation mediators in the pAAV8-CMV-mTFEB-injected brain compared with those in the control groups. Collectively, our results suggest that AAV8 successfully mediates mTFEB overexpression in the mouse brain without inducing apparent local inflammation, supporting the safety of TFEB-based gene therapy in treating neurodegenerative diseases.
基于转录因子EB（TFEB）的基因疗法是一种很有前景的治疗策略，可通过促进自噬/溶酶体介导的错误折叠蛋白的降解和清除来治疗神经退行性疾病，这些错误折叠蛋白会导致这些疾病的发病机制。然而，最近的研究结果表明TFEB具有促炎特性，这引发了对其临床应用安全性的担忧。为了研究TFEB是否会在大脑中诱导显著的炎症反应，将雄性C57BL/6小鼠注射磷酸盐缓冲盐水（PBS）、过表达小鼠TFEB的腺相关病毒血清型8（AAV8）载体（pAAV8-CMV-mTFEB）或在桶状皮质中表达绿色荧光蛋白（GFP）的AAV8载体。在注射后2个月收集脑组织样本。蛋白质印迹和免疫荧光染色显示，与注射PBS或过表达GFP载体的小鼠相比，注射过表达mTFEB载体的小鼠脑组织样本中mTFEB蛋白水平显著升高。pAAV8-CMV-mTFEB注射导致脑组织样本中溶酶体生物发生指标的mRNA和蛋白水平显著升高。与对照组相比，在注射pAAV8-CMV-mTFEB的大脑中，GFAP、Iba1和促炎介质的表达未观察到显著变化。总体而言，我们的结果表明AAV8成功介导了小鼠大脑中mTFEB的过表达，而不会诱导明显的局部炎症，这支持了基于TFEB的基因疗法在治疗神经退行性疾病方面的安全性。
