Table 1.

Antiviral Activity of Interferon Measured with Measles Virus in Cells Stably Deficient for either ADAR1 or PKR Compared to Control Cells^a

		Virus Yield
Cell	Virus	Untreated (TICD50/ml)	IFN-treated (TICD50/ml)
CONkd	WT	1.4 ± 0.3 × 106	1.3 ± 0.2 × 105
	Vko	1.0 ± 0.1 × 106	6.6 ± 1.7 × 104
	Cko	2.8 ± 0.1 × 104	2.6 ± 0.6 × 103
PKRkd	WT	1.0 ± 1.0 × 106	1.4 ± 0.1 × 105
	Vko	1.5 ± 0.3 × 106	1.1 ± 0.1 × 105
	Cko	8.0 ± 0.8 × 104	3.5 ± 0.3 × 103
ADAR1kd	WT	1.0 ± 0.1 × 106	1.4 ± 0.1 × 105
	Vko	4.3 ± 0.1 × 105	2.8 ± 0.2 × 104
	Cko	2.0 ± 0.5 × 104	6.8 ± 0.2 × 102

^aVirus yields were measured with the Moraten parental strain and mutants deficient in the expression of either V protien (V^ko) or C protein (C^ko) in puromycin-resistant control knockdown cells (CON^KD), ADAR1 stable knockdown (ADAR1^KD) and PKR stable knockdown (PKR^KD) HeLa cell clones either untreated or pretreated with 1000 units/mL IFNβ prior to infection. Yields were determined by 50% TICD₅₀ titation on Vero cells according to the Spearman-Karber method (Devaux 2008, Karber 1931). Results are means and standard errors (n=3).