Fig. 1

The HPV16 genome and our experimental epithelial model. Contained within the viral protein capsid (top left, not to scale relative to skin) is the 7.9 kb HPV16 genome, comprised of eight viral genes. Over a 14 day differentiation process we grew three-dimensional organotypic epithelia, or raft cultures, using near-diploid immortalized keratinocytes (NIKS) and primary human fibroblasts embedded in collagen-based dermal matrix. To permit the viral life cycle in this culture system we transfected the keratinocytes, prior to rafting, with complete viral genomes containing either the European Prototype or Asian-American variant of HPV16 E6 (EPE6 or AAE6, respectively). NIKS represented normal epithelia, NIKS with HPV16 EPE6 was a mild dysplasia (indicated by thickening and some suprabasal proliferation), whereas NIKS with HPV16 AAE6 was a moderate dysplasia (indicated by a greater number of suprabasal proliferating cells and abnormal cellular phenotypes, including micronuclei). Additionally, HPV16 viral integration was detected in AAE6 epithelia