Induction of type I IFN by C3.

<p>To confirm the production of type I IFN A549 (<b>A</b>) or VERO (<b>B</b>) cells were incubated with increasing concentrations of C3 for 24 hrs, the media with the compound was then removed, the cells washed with PBS (2×) and new media containing VSV-GFP was added. Twenty-four hrs later the GFP (as an indirect estimation of the viral replication, dashed gray line) and the ATP (as marker for the cell viability, solid line) were measured. ATP and GFP values in non-treated cells were set to 100%. Error bars represent standard deviation of three replicates. <b>C.</b> C3 induction of luciferase in the IFN-β MDCK reporter cell line. MDCK cells expressing firefly luciferase under the control of the IFN-β promoter were treated with C3 at the indicated concentration. After 24 hrs the luciferase signal was analyzed and standardized based on the values obtained in the mock treated cells.