Fig 7.

Levels of 16E5 expressed from epithelial cell lines harboring episomal HPV-16 genomes. (A) Chromatograms of D5-FLIT/FLIT transitions for deuterated internal standard added to tryptic digests of parental NIKS cells or NIKS-4H and NIKS-2L clonal cell lines harboring episomal copies of the HPV-16 genome. (B) Chromatograms of FLIT/IT transitions for endogenous FLIT peptide in the tryptic digests. No endogenous FLIT was detected in the parental NIKS cells. All retention times of the deuterated internal standards and endogenous FLIT were 28.88 ± 0.1 min (25-cm column).