Chandipura virus replication in Vero cells is inhibited by host restriction factors APOBEC3G and IFITM3

Chandipura virus (CHPV) is an emerging pathogen of Indian subcontinent and in some West African countries. The virus causes fever, encephalitis and death among young children and there is no vaccine or drug available till date to treat CHPV infection. The present study aims to investigate if CHPV replication is inhibited by interferon induced proteins, human APOBEC3G (hA3G) and IFITM3, which are known as antiviral host factors. Virus infectivity was determined by plaque assays and results showed that CHPV replication in Vero E6 cells was significantly inhibited by both hA3G and IFITM3 (90 % and 75 % respectively). Western blotting results showed that CHPV N proteins levels in the supernatants are in agreement with the plaque assays. Further analysis of CHPV infected and hA3G transfected cell supernatants showed that hA3G was not incorporated into CHPV virus particles. Analysis of virus RNA sequences indicated that hA3G does not cause induced mutation of CHPV genome during virus transcription/replication. This is the first report about the host factor mediated restrictions of CHPV and the present study warrant further in-depth studies to understand the mechanisms of inhibition of CHPV and other negative stranded RNA viruses by these factors.