Fig. 1.

Effect of PPMO on HeLa-H cells persistently infected with EAV (strain VB). Persistently infected HeLa-H cells (83rd passage, PI83) were subcultured for 10 passages in the presence of 0 μM, 1 μM, 5 μM, or 10 μM of EAV5′24 PPMO or SCR PPMO. Supernatants from each passage were harvested and titrated by plaque assay as described in the text. The average results from two experiments are presented (A, EAV5′24 PPMO; B, SCR PPMO). In parallel, standard RT-PCR (sRT-PCR) and real-time RT-PCR (rRT-PCR) analysis were carried out with RNA extracted from cell lysates at each passage and the results are shown below each graph (+RT-PCR, positive; −RT-PCR, negative). Representative sRT-PCR (expected PCR product size is 185 bp) and rRT-PCR results of persistently infected HeLa-H cells treated with 5 μM EAV5′24 PPMO (PI83 to PI92) are shown in C and D, respectively. Also included is RT-PCR analysis of PPMO-cured PI97 HeLa-H cells in which the 5 μM EAV5′24 PPMO treatment was stopped after passage 90.