Human papillomavirus L1 capsid protein (HPV L1)

The Human papillomavirus (HPV) L1 capsid protein is the primary structural component of the HPV virion, playing a critical role in viral attachment and entry into host cells (UniProt P03101). When recombinantly expressed, L1 proteins spontaneously self-assemble into virus-like particles (VLPs) that are morphologically and antigenically identical to the native virus but lack the viral genome, rendering them non-infectious (PubMed: 10666279). These VLPs serve as the potent antigenic target in prophylactic vaccines such as Gardasil 9 and Cervarix (FDA, 2014). The primary mechanism of action involves the induction of a robust humoral immune response, generating neutralizing antibodies that bind to conformational epitopes on the L1 protein (StatPearls: NBK548037). This binding prevents the virus from interacting with heparan sulfate proteoglycans on the basement membrane, thereby blocking the infection of basal keratinocytes (PubMed: 17164776). By preventing persistent infection with high-risk HPV types, these L1-targeted interventions effectively reduce the incidence of cervical, anogenital, and oropharyngeal cancers (WHO, 2022).

Other names

Major capsid protein L1HPV L1 virus-like particlesHPV L1 VLPL1 protein

Induction of a humoral immune response that produces high-affinity neutralizing antibodies; these antibodies bind to the L1 protein on the viral surface, sterically hindering viral attachment to host cell receptors and preventing entry into basal keratinocytes.