Recently, the research team led by Pro. Xiao Gengfu from WIV, CAS, has identified a 12-peptide P3 which inhibited Japanese encephalitis virus (JEV) infection of BHK-21 cells by interfering with viral attachment to host cells.

A phage display peptide library was panned against E DIII of JEV envelope protein, which plays an important role in the interaction of viral particles with host cell receptors, resulted in the identification of several peptides. One peptide, named P3, inhibited JEV infection of BHK-21 cells with an IC50 of ~1 μM and an IC90 at ~100 μM. Further characterization revealed that P3 bound to E DIII with a KD of 6.06×10-6 M and inhibited JEV infection by interfering with viral attachment to cells. Based on in silico prediction by ZDOCK, P3 was found to interact with E DIII via a hydrophobic pocket, which was confirmed by the binding assay of P3 to the V357A mutant. P3 was hypothesized to bind to E DIII by interacting with the sties adjacent to the BC and DE loops, which might interfere with the binding of JEV to cellular receptors, thus impeding viral infection. This newly isolated peptide may represent a new therapeutic candidate for treatment of JEV.