FIG. 2.

RT-PCR and ELISA of differential expression of IFN-inducible genes in cluster II. (A) RT-PCR analysis of IFN-regulated genes after infection of keratinocytes with HPV E6 and/or E7. Duplicate data are from two independent experiments. 2′-5′-OAS, 2′-5′ oligoadenylate synthase. (B) RT-PCR analysis of IFN-α and -β RNAs using consensus primer pairs for IFN. NC indicates the negative control in which no enzyme was added to the RT reaction. (C) ELISA analysis of intracellular IFN-α from one representative experiment. Keratinocytes were infected with HPV-16 E6, E6/E7, or p53DN. (D) ELISA analysis of intracellular IFN-α from three independent experiments. Cells were infected with HPV-16 oncogenes or p53DN mutant as above, with low-risk HPV-6 E6 or E7, or with sense p53 (p53+). Bars depict the means of three experiments, and brackets indicate standard errors. Changes other than HPV-6 E7 were statistically significant (Fisher's exact test).