Figure 7.

Exosome inhibitors suppress replication of enterovirus A71 (EV-A71) in differentiated C2BBe1 cells and improve survival rates of infected animals. (A) Differentiated C2BBe1 cells were treated with GW4869 (1 and 3 μM) or ketotifen (5 and 10 μM) and then infected with EV-A71 at a multiplicity of infection (MOI) of 10. Total cell lysates (supernatants and infected cells) were collected at 24 hours postinfection (h p.i.), and viral titers were quantified. (B) The plaque assay was also performed to quantify the released virus particles in the culture supernatants. (C) RD cells were treated with GW4869 (1 and 3 μM) or ketotifen (5 and 10 μM) and then infected with EV-A71 at an MOI of 2, and total cell lysates were collected at 24 h p.i. Plaque assays were performed to quantify the viral titers. (D) The released virus particles in the culture supernatants of RD cells were quantified with plaque-performing assay. (E) Transgenic mice expressing hSCARB-2 (hSCARB2-TG) mice were intragastrically administered 50 μL phosphate-buffered saline ([PBS] n = 9) or GW4869 (3 mM) (n = 10) 2 hours before EV-A71 challenge (2 × 10⁶ plaque-performing units [PFU]) via the oral route. The PBS or GW4869 were administered again at 1 day and 2 days p.i. The survival rates of infected animals were observed. Significant differences between 2 groups were determined by Student’s t test (*, P < .05; **, P < .01). DAPI, 4’,6-diamidino-2-phenylindole.