Metabolic Dependency Shapes Bivalent Antiviral Response in Host Cells: The Role of Glutamine

The establishment of effective antiviral responses within host cells is intricately related to their metabolic status, shedding light on immunometabolism. In this study, we investigated the hypothesis that cellular reliance on glutamine metabolism contributes to the development of a potent antiviral response. We evaluated the antiviral response in the presence or absence of L-glutamine in the culture medium, revealing a bivalent response hinging on cellular metabolism. While certain interferon-stimulated genes (ISGs) exhibited higher expression in an oxidative phosphorylation (OXPHOS)-dependent manner, others were surprisingly upregulated in a glycolytic-dependent manner. This metabolic dichotomy was influenced in part by variations in IFN-β expression. We initially demonstrated that the presence of L-glutamine induced an enhancement of oxidative phosphorylation in A549 cells. Furthermore, in cells stimulated poly:IC, a marked increase in ISGs expression was observed in a dose-dependent manner with L-glutamine supplementation. Interestingly, our findings unveiled a metabolic dependency in the expression of specific ISGs. In particular, genes such as ISG54, ISG12 and ISG15 exhibited heightened expression in cells cultured with L-glutamine, corresponding to higher OXPHOS rates and IFN-β signaling. Conversely, the expression of viperin and 2’-5’-oligoadenylate synthetase 1 was inversely related to L-glutamine concentration, suggesting a glycolysis-dependent regulation, confirmed by inhibition experiments. This study highlights the intricate interplay between cellular metabolism, especially glutaminergic and glycolytic, and the establishment of the canonical antiviral response characterized by the expression of antiviral effectors, potentially paving the way for novel strategies to modulate antiviral responses through metabolic interventions. ### Competing Interest Statement The authors have declared no competing interest. * 2-DG : 2-deoxyglucose A549Dual : A549-Dual™, expressing NF-κB-SEAP and IRF-Luc reporters GAS : Gamma interferon activation site IFN : Interferon IFNAR : IFNs 12/β receptor IRF : Interferon Regulatory Factor ISG : Interferon Stimulated Gene ISRE : IFN-stimulated response element mROS : Mitochondrial reactive oxygen species OXPHOS : Oxidative phosphorylation PIC : Poly(I:C) (HMW) / LyoVec™