FIG. 1.

Expression of E6 proteins extends the life span of primary keratinocytes in culture. A. Primary keratinocytes expressing beta-E6 proteins were grown in culture to compare their growth properties to control cells containing an LXSN empty vector. Cells were passaged at 80% confluence and recorded for population doublings under normal cell growth conditions. Error bars were calculated using the standard deviation of three independent experiments. B. P values for each E6 cell line compared to each other and to an LXSN control are shown. The P values were calculated using a one-way analysis of variance with Bonferroni post hoc analysis. NS, not significant.