Interaction of human papillomavirus type 16 and adeno-associated virus type 2 co-infecting human cervical epithelium

Recently, we hypothesized that the tumour-suppressive, human helper-virus-dependent, adeno-associated parvoviruses (AAV) may interfere with transforming functions of human papillomaviruses (HPV) in the development of cervical carcinoma. Here, we demonstrate that in cervical epithelium containing papillomavirus DNA, AAV DNA can be detected in a replication-competent form and that AAV proteins are expressed. In cultured cells containing integrated AAV-2 DNA, transfection of HPV-16 DNA induced rescue of infectious AAV-2, revealing helper functions of HPV-16. Similarly, cotransfection of HPV-16 and AAV-2 DNAs into human epithelial cell lines led to replication of AAV-2, and, in keratinocytes, to a cytopathic effect. These data suggest an interaction of the two viruses, possibly influencing the development of HPV-related lesions.