FIG 8.

A deficiency of ISG20 leads to increased CHIKV and VEEV-G3A replication in primary cells. Primary cells were isolated from age- and sex-matched B6 and Isg20^−/− mice. Cells were treated with 0, 10, or 100 IU/ml IFN-α4/β (1:1 ratio) for 4 h and then infected with (A and B) CHIKV or (C and D) VEEV-G3A (MOI = 1). Virus titers were determined at 24 h.p.i. by plaque assay. (E) ISG induction was measured in uninfected, 6-h IFN-treated B6 or Isg20^−/− MEFs by qPCR. *, P < 0.05; **, P < 0.01; ***, P < 0.001 (multiple Student’s t tests). (A to D) n = 6, 2 independent experiments. (E and F) n = 3, 2 independent experiments.