Major capsid protein L1, Human papillomavirus type 45 (HPV45 L1)

The **major capsid protein L1 of human papillomavirus type 45** is the principal structural protein forming the outer shell (capsid) of the virus. L1 assembles into pentamers that self-organize into an icosahedral capsid comprising 72 pentamers linked by disulfide bonds, encapsidating the viral genome and mediating virus stability and infectivity[1][6]. When expressed recombinantly, L1 can form virus-like particles that mimic the native virion surface and serve as immunogens in prophylactic HPV vaccines[3]. The immune response to L1 virus-like particles is highly protective, inducing type-specific neutralizing antibodies that prevent HPV infection[3]. The protein also plays a role in stabilizing the viral genome and in processes required for viral entry into host cells[2]. L1 is highly conserved among papillomaviruses and has been central to the success of HPV vaccines in preventing cervical and other HPV-associated cancers[3][5][6].

Other names

L1 protein, Human papillomavirus type 45HPV45 L1 capsid proteinHPV type 45 L1

Vaccines containing recombinant L1 virus-like particles elicit neutralizing antibodies that block HPV infection by preventing viral entry into host cells[3].