Glutathione-Capped Ag2S Nanoclusters Inhibit Coronavirus Proliferation through Blockage of Viral RNA Synthesis and Budding

Development of novel antiviral reagents is of great importance for the control of virus spread. Here, Ag2S nanoclusters (NCs) were proved for the first time to possess highly efficient antiviral activity by using porcine epidemic diarrhea virus (PEDV) as a model of coronavirus. Analyses of virus titers showed that Ag2S NCs significantly suppressed the infection of PEDV by about 3 orders of magnitude at the noncytotoxic concentration at 12 h postinfection, which was further confirmed by the expression of viral proteins. Mechanism investigations indicated that Ag2S NCs treatment inhibits the synthesis of viral negative-strand RNA and viral budding. Ag2S NCs treatment was also found to positively regulate the generation of IFN-stimulating genes (ISGs) and the expression of proinflammation cytokines, which might prevent PEDV infection. This study suggest the novel underlying of Ag2S NCs as a promising therapeutic drug for coronavirus.