Human papillomavirus L1 and L2 capsid proteins (HPV L1 and L2)

The **L1 and L2 capsid proteins of human papillomavirus (HPV)** are the major (L1) and minor (L2) structural proteins that self-assemble into the virus's outer icosahedral capsid, which is essential both for protecting the viral DNA genome and for mediating infection of host epithelial cells[1][2][6]. L1 forms 72 pentamers that create the main framework of the capsid, stabilized by disulfide bonds, while L2 is incorporated at substoichiometric levels, interacting with L1 and positioned centrally within capsomers[1][3][6]. L1 mediates initial attachment and entry into cells and is the dominant antigen in current prophylactic vaccines; L2 plays critical roles in viral genome encapsidation, proper trafficking through the endocytic and endosomal systems during infection, and also exposes conserved epitopes that are of growing interest for broader vaccine strategies[2][3][5]. Both proteins are foundational to HPV biology, vaccine design, and molecular screening strategies in cervical and other HPV-associated cancers[2][5].

Other names

HPV major capsid protein L1HPV minor capsid protein L2papillomavirus capsid proteins

Induction of neutralizing antibodies (L1 VLP vaccines), blockade of virus entry/trafficking, prevention of capsid assembly