Xu Jinxian, Zhang Xinyan, Liao Yi, Shi Ting, Marshall Brendan, Zhang Ming
Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA.
James and Jean Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA.
Viruses. 2025 Sep 3;17(9):1206. doi: 10.3390/v17091206.
(1) Background: Retinal degeneration develops upon caspase-12 activation in aged BALB/c mice following systemic neonatal infection. (2) Methods: MCMV or medium was injected intraperitoneally (i.p.) into caspase-12 and caspase-12 mice (on BALB/c background) at <3 days after birth. At 8 and 12 months post infection (p.i.), eyes were analyzed by SD-OCT before eyes and extraocular tissues were collected and analyzed by plaque assay, H&E staining, TUNEL assay, Western blot and real-time RT-PCR. (3) Results: Virus DNA, but not replicating virus, was present in eyes and extraocular tissues at 8 and 12 months p.i. Several MCMV genes were expressed in eyes of both MCMV-infected caspase-12 and caspase-12 mice, while mean retinal thickness was significantly higher in MCMV latently infected aged caspase-12 mice compared to age-matched infected caspase-12 mice. Although similar levels of cleaved caspase-1 were detected in eyes of both infected caspase-12 and control mice, significantly higher levels of activated NF-κB, cleaved caspase-8, MLKL, p-RIP3 and p53 were observed in eyes of infected caspase-12 mice compared to eyes of infected caspase-12 mice. (4) Conclusions: Our results suggest that caspase-12 contributes to retinal degeneration during MCMV ocular latency via multiple pathways including apoptosis and necroptosis.
(1) 背景：在新生期全身性感染后的老年BALB/c小鼠中，视网膜变性在半胱天冬酶 - 12激活后发生。(2) 方法：在出生后<3天，将巨细胞病毒（MCMV）或培养基腹腔内注射到（BALB/c背景的）半胱天冬酶 - 12基因敲除和野生型半胱天冬酶 - 12小鼠体内。在感染后8个月和12个月，通过光谱域光学相干断层扫描（SD - OCT）分析眼睛，然后收集眼内和眼外组织，通过蚀斑测定、苏木精 - 伊红（H&E）染色、末端脱氧核苷酸转移酶介导的缺口末端标记（TUNEL）测定、蛋白质免疫印迹和实时逆转录 - 聚合酶链反应（RT - PCR）进行分析。(3) 结果：在感染后8个月和12个月，病毒DNA而非复制型病毒存在于眼内和眼外组织中。在感染MCMV的半胱天冬酶 - 12基因敲除和野生型半胱天冬酶 - 12小鼠的眼睛中均表达了多个MCMV基因，而与年龄匹配的感染野生型半胱天冬酶 - 12小鼠相比，MCMV潜伏感染的老年半胱天冬酶 - 12基因敲除小鼠的平均视网膜厚度显著更高。尽管在感染野生型半胱天冬酶 - 12和对照小鼠的眼睛中检测到相似水平的裂解半胱天冬酶 - 1，但与感染野生型半胱天冬酶 - 12小鼠的眼睛相比，在感染半胱天冬酶 - 12基因敲除小鼠的眼睛中观察到显著更高水平的活化核因子 - κB（NF - κB）、裂解半胱天冬酶 - 8、混合谱系激酶结构域样蛋白（MLKL）、磷酸化受体相互作用蛋白3（p - RIP3）和p53。(4) 结论：我们的结果表明，半胱天冬酶 - 12通过包括凋亡和坏死性凋亡在内的多种途径，在MCMV眼部潜伏期间促成视网膜变性。
