The FDA-Approved Oral Drug Nitazoxanide Amplifies Host Antiviral Responses and Inhibits Ebola Virus

Jasenosky, Luke D.; Cadena, Cristhian; Mire, Chad E.; Borisevich, Viktoriya; Haridas, Viraga; Ranjbar, Shahin; Nambu, Aya; Bavari, Sina; Soloveva, Veronica; Sadukhan, Supriya; Cassell, Gail H.; Geisbert, Thomas W.; Hur, Sun; Goldfeld, Anne E.

The A549 cells with CRISPR/dCas9-KRAB-based knock down of: i) PKR, ii) RIG-I, or iii) GADD34 were used to assess the mechanism of NTZ EBOV inhibition through these genes. For this analysis, we infected cells in duplicate with the Zaire ebolavirus Kikwit strain (EBOV). After 1 hour in DMEM+1%FBS cells were treated with 20 µM NTZ for 4 hours before EBOV infection. After the 4-hour pre-treatment, the supernatants from the NTZ-treated cells were removed and then used to make up the EBOV inocula per condition. Cells were inoculated at an MOI of 0.01, which was rocked at 37°C for one hour. The inocula were left on the cells and had fresh media containing 20 µM NTZ added. Supernatants were collected at 1, 48, and 72 hours post infection and analyzed for production of infectious virus by plaque assay analysis.