Non-polio enterovirus capsid protein (NPEV capsid)

Non-polio enteroviruses (NPEVs) are a diverse group of pathogens within the Picornaviridae family, encompassing species such as Coxsackievirus, Echovirus, and numbered Enteroviruses like EV-A71 and EV-D68 (CDC, 2024). The viral capsid is a pseudo-icosahedral shell composed of 60 copies each of four structural proteins: VP1, VP2, VP3, and VP4, which protect the viral RNA and mediate host cell attachment and entry (Baggen et al., 2018). Epitopes on the capsid surface, particularly the "canyon" region and the VP1 loops, are the primary targets for neutralizing antibodies and are central to the development of vaccines and therapeutic monoclonal antibodies (Xu et al., 2019). Additionally, the capsid contains a conserved hydrophobic "pocket" beneath the canyon floor that is the target for small-molecule antiviral drugs known as capsid binders, such as pleconaril (Pevear et al., 1999). These drugs stabilize the capsid to prevent the uncoating process necessary for genome release. Because NPEVs are responsible for a wide range of clinical manifestations, including hand, foot, and mouth disease, myocarditis, and acute flaccid myelitis, the capsid remains a critical focus for both preventative and curative medical interventions (Puenpa et al., 2019).

Other names

Enterovirus capsidNPEV structural proteinsVP1, VP2, VP3, and VP4 proteinsEnterovirus capsid antigen

Capsid binders occupy a hydrophobic pocket within the VP1 protein, stabilizing the capsid and preventing the conformational changes required for viral uncoating and genome release into the host cell (Pevear et al., 1999). Neutralizing antibodies bind to surface epitopes to block receptor attachment or viral entry (Xu et al., 2019).