FIG. 6.

Expression of capsid proteins follows expression of E4 in lesions caused by different papillomavirus types. Tissue sections of lesions caused by COPV, ROPV, HPV11, CRPV, and HPV2 were double stained using antibodies to the L1 capsid protein (red) and E4 (green) before being counterstained with DAPI (blue). The merged images (m) are shown on the left. Although E4 expression always precedes the expression of L1, the distance between the first appearance of E4 and the first appearance of L1 varied considerably. The positions of the basal layers are indicated by broken lines. The images were taken using a 10× (HPV2, HPV11, and COPV) or 20× (CRPV) objective.