Figure 2From: Avian influenza virus H5N1 induces rapid interferon-beta production but shows more potent inhibition to retinoic acid-inducible gene I expression than H1N1 in vitroH5N1 infection induced low level endogenous RIG-I expression. The A549 cells were infected with H5N1 or H1N1 (m.o.i = 2) for 1 h, then the supernatant was replaced with fresh medium and culturing was continued. At the indicated time, the cells were collected. Half of the cells were used to detect endogenous RIG-I expression, and human β-actin was used as the loading control. The other half of the cells was used to extract total RNA and synthesize cDNA as previously demonstrated. Semiquantitative PCR was used to detect the RIG-I and human β-actin mRNA level.Back to article page