Department of Pharmacology and Toxicology, School of Pharmacy, University of Arizona, Tucson, AZ 85721, USA.
Department of Biosystems Engineering, University of Arizona, Tucson, AZ 85721, USA.
Int J Mol Sci. 2022 May 16;23(10):5557. doi: 10.3390/ijms23105557.
Current options for preventing or treating influenza are still limited, and new treatments for influenza viral infection are urgently needed. In the present study, we serendipitously found that a small-molecule inhibitor (AG1478), previously used for epidermal growth factor receptor (EGFR) inhibition, demonstrated a potent activity against influenza both in vitro and in vivo. Surprisingly, the antiviral effect of AG1478 was not mediated by its EGFR inhibitory activity, as influenza virus was insensitive to EGFR blockade by other EGFR inhibitors or by siRNA knockdown of EGFR. Its antiviral activity was also interferon independent as demonstrated by a Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) knockout approach. Instead, AG1478 was found to target the Golgi-specific brefeldin A-resistance guanine nucleotide exchange factor 1 (GBF1)-ADP-ribosylation factor 1 (ARF1) system by reversibly inhibiting GBF1 activity and disrupting its Golgi-cytoplasmic trafficking. Compared to known GBF1 inhibitors, AG1478 demonstrated lower cellular toxicity and better preservation of Golgi structure. Furthermore, GBF1 was found to interact with a specific set of viral proteins including M1, NP, and PA. Additionally, the alternation of GBF1 distribution induced by AG1478 treatment disrupted these interactions. Because targeting host factors, instead of the viral component, imposes a higher barrier for developing resistance, GBF1 modulation may be an effective approach to treat influenza infection.
目前预防或治疗流感的选择仍然有限，迫切需要新的流感病毒感染治疗方法。在本研究中，我们偶然发现一种小分子抑制剂（AG1478），以前用于表皮生长因子受体（EGFR）抑制，在体外和体内均对流感具有强大的活性。令人惊讶的是，AG1478 的抗病毒作用不是通过其 EGFR 抑制活性介导的，因为流感病毒对其他 EGFR 抑制剂或 EGFR 的 siRNA 敲低阻断 EGFR 不敏感。其抗病毒活性也不依赖干扰素，如通过规律成簇间隔短回文重复序列（CRISPR）敲除方法证明的那样。相反，AG1478 被发现通过可逆抑制 GBF1 活性并破坏其高尔基体-细胞质运输来靶向高尔基体特异性布雷菲德菌素 A 抗性鸟嘌呤核苷酸交换因子 1（GBF1）-ADP-核糖基化因子 1（ARF1）系统。与已知的 GBF1 抑制剂相比，AG1478 表现出更低的细胞毒性和更好的高尔基体结构保存。此外，GBF1 被发现与一组特定的病毒蛋白相互作用，包括 M1、NP 和 PA。此外，AG1478 处理诱导的 GBF1 分布改变破坏了这些相互作用。因为针对宿主因子而不是病毒成分会增加产生耐药性的难度，因此调节 GBF1 可能是治疗流感感染的有效方法。
