Poliovirus type 3 (Sabin strain) antigen (PV3 (Sabin))

Sabin poliovirus type 3 antigen is a live-attenuated viral component derived from the Leon 12a1b strain, primarily used in the production of the oral poliovirus vaccine (OPV) (Sutter et al., 2018, Plotkin's Vaccines). It functions as a primary immunogen, presenting viral capsid proteins (VP1, VP2, VP3, and VP4) to the host immune system to elicit the production of neutralizing antibodies and mucosal IgA (Minor, 1992, Nature). This immune response provides protection against poliomyelitis, a debilitating disease caused by wild-type poliovirus type 3 (WHO, 2023). Unlike types 1 and 2, the Sabin type 3 strain is characterized by a specific set of mutations, notably at position 472 in the 5' untranslated region, which reduce its neurovirulence (Evans et al., 1985, Nature). However, it is the most genetically unstable of the Sabin strains, frequently undergoing back-mutations that can lead to vaccine-associated paralytic poliomyelitis (VAPP) or circulating vaccine-derived polioviruses (cVDPV) (CDC, 2022). In clinical practice, it is administered to ensure comprehensive coverage against poliovirus serotypes, though many countries have transitioned to inactivated polio vaccines (IPV) to mitigate the risk of reversion (Global Polio Eradication Initiative).

Other names

Poliovirus type 3 (Sabin strain)Sabin 3OPV3 antigenLive-attenuated poliovirus type 3

Induction of neutralizing antibodies and mucosal immunity (IgA) through active immunization.