傳染性脾臟與腎臟壞死病毒（infectious spleen and kidney necrosis virus, ISKNV），隸屬於虹彩病毒科（Iridoviridae）巨噬細胞病毒屬（Megalocytivirus），為水產養殖魚類重要病原之一，常造成宿主高死亡率及造成嚴重的經濟損失。已有研究指出，ISKNV 感染可誘發多種程序性細胞死亡（programmed cell death, PCD）反應，包括細胞凋亡、細胞自噬及鐵凋亡（Ferroptosis）；然而，其於感染過程中是否亦涉及程序性壞死（Necroptosis）之調控，至今仍未完全釐清。因此，本研究以石斑魚鰭細胞株 GF-1 為體外(in vitro)感染模型，並輔以實驗室既有之活體感染石斑魚轉錄體學與代謝體學資料作為延伸分析，探討 ISKNV 感染過程中鐵凋亡與程序性壞死之可能參與機制。此外，本研究以鐵凋亡抑制劑 Ferrostatin-1（Fer-1）進行處理，以評估其對 ISKNV 感染所引發細胞損傷之緩解效果。
研究結果顯示，ISKNV 感染可於 GF-1 細胞中誘發明顯細胞病變，並伴隨活性氧（reactive oxygen species, ROS）累積增加。於程序性壞死相關分析中，終端執行分子 MLKL 之表現受感染影響而上升，顯示 ISKNV 感染可能活化程序性壞死路徑。於鐵凋亡相關分析中，GPX4 等關鍵分子表現出現變化，並與氧化壓力增加及脂質累積量相關現象相互呼應，顯示 ISKNV 感染可能亦涉及鐵凋亡之調控。另一方面，活體轉錄體學分析結果亦支持病毒感染後宿主氧化還原平衡、脂質代謝與細胞壓力反應途徑發生改變，進一步提供 ISKNV 感染可能涉及多重細胞死亡與氧化壓力調控之佐證。經 Fer-1處理後，部分與氧化壓力及細胞死亡相關指標呈下降趨勢，顯示抑制脂質累積量與降低氧化壓力可能有助於緩解 ISKNV 所造成之細胞損傷。
綜合上述結果，ISKNV 感染 GF-1 細胞可能透過擾亂細胞內氧化還原平衡，進而誘導鐵凋亡與程序性壞死之發生；而 Ferrostatin-1處理則對此病理過程具有一定程度之緩解作用。本研究不僅有助於釐清 ISKNV 感染與宿主細胞死亡調控間之關聯，亦可作為未來發展石斑魚病毒感染防治策略及抗氧化干預應用之參考。

Infectious spleen and kidney necrosis virus (ISKNV), a double-stranded DNA virus belonging to the family Iridoviridae and genus Megalocytivirus, is a major pathogen in aquaculture that causes high mortality and economic loss in grouper. Although ISKNV has been reported to induce oxidative stress and programmed cell death, whether Ferroptosis and Necroptosis are simultaneously involved remains unclear. This study investigated the roles of Ferroptosis and Necroptosis during ISKNV infection in GF-1 cells and evaluated the protective effects of Ferrostatin-1 treatments. Western blotting and quantitative PCR were used to examine cell death-related markers, while supportive transcriptomic and metabolomic datasets from experimentally infected grouper were analyzed to assess changes in oxidative stress, lipid metabolism, and cell death-related pathways using antioxidant treatment. The results showed that ISKNV infection increased reactive oxygen species accumulation and altered the expression of key Ferroptosis and Necroptosis-related molecules. Treatment with Ferrostatin-1 reduced some of these infection-associated changes. These findings suggest that ISKNV may induce both Ferroptosis and Necroptosis through disruption of redox homeostasis, and that antioxidant-based treatments may help alleviate ISKNV-induced cellular damage.

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