Human papillomavirus type 45 L1 capsid protein (L1)

The Human papillomavirus type 45 L1 capsid protein is the primary structural component of the HPV-45 virion, self-assembling into an icosahedral shell with T=7 symmetry that protects the viral genome [2, 10]. Its central biological function is mediating the initial attachment of the virus to heparan sulfate proteoglycans on the basement membrane and host cell surface, which triggers conformational changes required for viral entry into keratinocytes [5, 12, 18]. As a high-risk HPV genotype, persistent infection with HPV-45 is a significant cause of cervical cancer, particularly adenocarcinoma, as well as vulvar, vaginal, and anal malignancies [1, 6, 15]. The L1 protein serves as the active antigen in the 9-valent HPV vaccine (Gardasil 9), where it is formulated as recombinant virus-like particles (VLPs) to stimulate the production of neutralizing antibodies [3, 7, 8]. These antibodies bind to the L1 capsid and prevent the virus from infecting the host epithelium, providing high prophylactic efficacy [9, 11, 13]. However, L1-targeted vaccines are strictly preventive and do not provide therapeutic benefits for patients with pre-existing HPV-45 infections or established cancerous lesions [3, 17].

Other names

Major capsid protein L1HPV45 L1HPV-45 major capsid proteinL1 major capsid proteinL1 protein

Induces the production of neutralizing antibodies that bind to the viral L1 capsid, preventing viral attachment to host cell receptors and subsequent infection