Fig. 2

The effect of secreted porcine β -IFN on cell cycle progression

(A) Supernatants from vsmc infected with ADV-β-IFN (■) or ADV-ΔE1 (♦) were analyzed for antiproliferative effects at the indicated concentrations of conditioned media. Cell proliferation was measured using the MTT colorimetric assay, detecting optical density at 570–650 to determine relative rates of proliferation as described previously (3). (B) Propidium iodide staining was used to determine cell cycle distribution of vsmc after infection using the indicated antiviral vectors. The percentage of cells in G0/G1, S, and G2/M are shown for each vector, respectively. (C) Western blot analysis for β-IFN protein in control (pCMV) or β-IFN (pCMV-β-IFN) transfected 293 cells. Western blots were performed as previously described (11, 13) using a sheep anti-human β-IFN antibody (Biosource International, Camerillo, CA).