Yupingfeng Formula Exerts Antiviral Property by Promoting IFN-I Production and IgG1 Antibody Response.

Yupingfeng (YPF) is a classic formula of traditional Chinese medicine and has been widely used to prevent and treat respiratory virus infectious diseases. However, the pharmacological mechanism underlying the antiviral activity of YPF remains elusive. In the present study, we evaluated the ability of YPF to promote type I interferon (IFN-I) production in vitro, subsequently inducing expression of numerous interferon-stimulated genes that exert antiviral activities. In addition, by employing an advanced bioluminescence imaging-based mouse model of influenza virus infection, we monitored the alteration of viral kinetics in vivo upon YPF treatment in real time. As a result, our findings demonstrated that YPF predominantly reduces the viral load in animals at later stages of infection. Further mechanistic studies suggested that YPF can especially enhance the Th2 polarization and IgG1 antibody response, accelerating the elimination of invading viruses. Our study provides consolidated evidence for the antiviral properties of YPF and will facilitate its clinical use and further development.