Review of HPV antigenic epitope and its application in vaccines development

Cervical cancer,caused by human papilloma virus (HPV),is the fourth most susceptible cancer in women all over the world,so the research and development of its corresponding vaccine has also been a hot spot in many studies.The main pathogenic proteins of HPV include two capsid proteins L1,L2 and two oncoproteins E6,E7.As the main antigen of HPV,the epitope of L1 can be divided into linear epitope,conformation epitope and B/T cell epitope.Some of the linear epitopes (HPV16-L1 protein RHGEEYDLQFIFQLCKITLTA,HPV 18-L1 protein PVPGQYDATK and other epitopes) and conformation epitopes (H16U4,H16V5,etc.),and B and T cell epitopes in HPV16-L1 fragments (H2,H3,H4,H9,H11,H12) have the potential to become the targets of developing a vaccine with L1 as the main antigen.Recently,the focus of many studies has been changed to L2 protein due to its protective effect on different types of HPV,especially for L2 N-terminal protein that can get different characteristics when combined with different virus-like particles and adjuvants.Moreover,the protective range of L2 vaccine is more extensive than L1.E6 and E7-specific phenotypic peptides and CpG vaccine are also new directions for the study of HPV therapeutic vaccine.This article will elaborate on the latest research progress of HPV vaccine and its related epitopes.