FIG 1.

HPV38 E6 and E7 downregulate TLR9 expression. (A) RPMI 8226 cells were cotransfected with the TLR9 promoter construct (−3227/−1) fused with the luciferase reporter gene and with pLXSN empty vector (pLXSN), pLXSN HPV16 E6/E7 (HPV16), or HPV38 E6/E7 (HPV38). After 48 h, cells were harvested and luciferase activity was measured. Data are the means from three independent experiments performed in triplicate. **, P < 0.01. (B) Total RNA and total proteins from HFK and HPV38 E6/E7 HFK were extracted, and TLR9 expression levels were measured by RT-qPCR and normalized to glyceraldehyde-3-phosphate dehydrogenase (GAPDH) levels (left); in addition, TLR9 protein levels were determined by immunoblotting (right). Error bars on the left side represent standard deviations from three biological replicates. **, P < 0.01. (C) Total RNA from control HFK or the indicated transduced HFK was extracted. TLR9 expression levels were measured by RT-qPCR. Error bars represent standard deviations from three biological replicates. (D) HFK transduced with pLXSN, HPV38 E6/E7, or HPV16 E6/E7 were treated with GpC or CpG 2006. After 24 h, the supernatants were collected to measure IL-8 or MIP3α secretion. Data are the means from three independent experiments performed in triplicate. **, P < 0.01.