Screening Potential Anti‐Respiratory Syncytial Virus Substances From Forsythia suspensa Using a High‐Expressing Fusion Protein Cell Membrane Chromatography

Respiratory syncytial virus (RSV) imposes a substantial health burden, particularly among pediatric and elderly populations. The RSV fusion (F) protein, a critical mediator of viral entry and syncytium formation, represents a promising and rational target for antiviral drug development. Forsythia suspensa (Lianqiao in Chinese), a traditional Chinese medicinal herb, has been empirically employed for decades in the prevention of viral infections; however, its pharmacologically active constituents remain poorly characterized. The present investigation developed a high-expression F protein cell membrane chromatography system, and integrated with UHPLC-MS, to screen pharmacological substances from FS and verified the anti-viral potential against RSV in vivo. Our study pinpointed Forsythoside A, Forsythoside B, Phillygenin, and Phillyrin as potential anti-RSV compounds in FS. The research findings suggest that Forsythoside A, Forsythoside B, and Phillygenin exhibit considerable suppressive effects on cell fusion induced by RSV, concurrently effectively diminishing the expression level of the F protein gene. In contrast, the inhibitory impact of Phillyrin seems relatively less potent. In conclusion, our findings provide a convenient, fast, and accurate method to screen potential anti-RSV ingredients in natural herbal medicines. These results may facilitate the development of RSV treatment.