Evidence for the coexistence of two genital HPV types within the same host cell in vitro.

Studies on the presence of human papillomavirus (HPV) DNA in cervical samples show that 10% or more of all clinical lesions contain at least two different HPV types. We have investigated if multiple HPV types can exist in the same cell and interact with one another or if they merely exist in the same tissue. Combinations of genital HPV genomes were electroporated into primary keratinocytes. Southern analyses of the electroporated cultures indicate that while a subset of high-risk HPV types can be stably maintained and replicate episomally in the same cell, interactions between types do occur, often to the detriment of one or both viruses in question. These studies provide insight into the interactions that may occur between HPV types in naturally occurring lesions.