Figure 4.

(A) HPV-18 DNA amplification in differentiated keratinocytes lags behind cellular DNA replication. HPV-18-containing PHK raft cultures were harvested on days 8, 10, 12, and 14, each following a 12-h incubation with BrdU. Sections were probed for HPV-18 DNA (red) and incorporated BrdU (green). Cellular DNA was revealed by DAPI (blue). (Left column) For better visualization of tissue morphology, DAPI staining is also presented in black-and-white images. (B) Detection of viral DNA (red) and the major capsid protein L1 (green) in a 14-d-old culture.