Semen-derived enhancer of viral infection (SEVI) is composed of amyloid fibrils that can greatly enhance HIV-1 infectivity.By its cationic property,SEVI promotes viral sexual transmission by facilitating the attachment and internalization of HIV-1 to target cells.Therefore,semen-derived amyloid fibrils are potential targets for microbicide design.ADS-J1 is an anionic HIV-1 entry inhibitor.In this study,we explored an additional function of ADS-J1 :inhibition of SEVI fibril formation and blockage of SEVI-mediated enhancement of viral infection.