Human papillomavirus minor capsid protein L2 (L2)

The human papillomavirus minor capsid protein L2 is a structural viral protein present at low copy number in the non-enveloped, icosahedral papillomavirus particle. While the major capsid protein L1 forms most of the capsid and can self-assemble, L2 co-assembles with L1, contributing critically to the encapsidation of the viral double-stranded DNA genome and enhancing capsid stability and assembly[1][4][5][7]. During infection, L2 is essential for mediating viral escape from endosomes and trafficking the viral genome to the nucleus by interacting with host cellular factors; a large portion of L2 is intrinsically disordered, providing flexibility for its roles in DNA binding, interaction with L1, and cytosolic trafficking[2][8]. L2-directed antibodies exhibit cross-neutralizing activities against a broad range of HPV types, making L2 an important investigational target for pan-HPV vaccine strategies, though its overall immunogenicity is lower than L1[5][6]. No direct therapeutic drugs currently target L2, but it is under active investigation as a component of broadly protective HPV vaccines[6].

Other names

Papillomavirus L2 proteinHPV L2Minor capsid protein L2

Antibody-mediated neutralization: L2-targeted antibodies can neutralize diverse HPV types by interfering with viral entry; Vaccine antigen: L2-based vaccines aim to elicit cross-protective immune responses by targeting conserved regions