Immunotherapy of human papillomavirus-associated malignancies and the challenges posed by T-cell tolerance.

Human papillomaviruses are associated with a broad range of carcinomas, including cervical cancer. Although the delivery of immunogenic tumor-associated antigens represents a promising approach in the treatment of these malignancies, the imposition of T cell tolerance poses a significant challenge in this endeavor. The purpose of this review is to discuss T cell tolerance and the role of T cell costimulation in the immunotherapy of HPV-associated malignancies.