Poliovirus type 1 (Sabin) capsid protein (PV1 (Sabin) capsid)

The Poliovirus Sabin type 1 capsid neutralizing epitopes are specific antigenic regions on the surface of the poliovirus type 1 (Sabin strain) virion, primarily located on the structural proteins VP1, VP2, and VP3 (PubMed: 2470444). These epitopes are organized into distinct neutralizing antigenic sites (N-Ag I, II, IIIa, and IIIb) that are recognized by the host's B-cell receptors and antibodies (PubMed: 1695466). The primary biological function of the capsid is to protect the viral RNA genome and facilitate entry into host cells by binding to the poliovirus receptor, CD155 (UniProt: P03300). In the context of immunization, these epitopes are the targets of the Oral Poliovirus Vaccine (OPV) and Inactivated Poliovirus Vaccine (IPV), which stimulate the production of neutralizing antibodies to prevent poliomyelitis (PubMed: 30115705). While the Sabin 1 strain is attenuated, it remains genetically unstable, and mutations within or near these capsid regions can contribute to the reversion of the virus to a neurovirulent phenotype (PubMed: 8295330). Therapeutic interventions, such as the antiviral drug Pocapavir, target the hydrophobic pocket within the VP1 protein to inhibit viral uncoating (PubMed: 25332251). Consequently, these epitopes are central to both the efficacy of current vaccines and the challenges associated with vaccine-derived poliovirus outbreaks.

Other names

Sabin 1 capsidPV1 Sabin epitopesPoliovirus type 1 structural proteinsPoliovirus type 1 (Sabin) neutralizing antigenic sitesVP1/VP2/VP3/VP4 complex

Induction of neutralizing antibodies that bind to capsid epitopes, sterically hindering the interaction between the virus and the host receptor CD155, thereby preventing viral internalization (PubMed: 1695466). Antiviral drugs like Pocapavir bind to the hydrophobic pocket of the VP1 protein to prevent viral uncoating (PubMed: 25332251).