Inactivated poliovirus antigen type 2 (IPV2)

Inactivated poliovirus antigen type 2 is the specific antigenic component of the inactivated poliovirus vaccine (IPV) derived from the MEF-1 (Middle East Forces 1) strain of Poliovirus Type 2 [DrugBank, WHO]. It is produced by treating the live virus with formaldehyde, which renders the virus non-infectious and unable to replicate while maintaining the structural integrity of its capsid proteins (VP1-VP4) [Wikipedia, PAHO]. The primary biological function of this antigen is to induce a systemic humoral immune response, specifically the production of neutralizing IgG antibodies that prevent the virus from attaching to the human poliovirus receptor (CD155) [PAHO, MDPI]. This protection is vital for preventing paralytic poliomyelitis, a devastating neurological disease [Wikipedia, UNICEF]. Although wild poliovirus type 2 was eradicated globally in 2015, the antigen remains essential for managing the risk of circulating vaccine-derived polioviruses (cVDPV2) [PAHO, PubMed]. Unlike the oral polio vaccine, the inactivated antigen does not carry the risk of reverting to virulence, but it provides less robust intestinal mucosal immunity [PAHO, CDC]. In addition to its role in vaccines, the viral capsid represented by this antigen is a target for experimental antiviral drugs like pocapavir, which bind to the capsid's hydrophobic pocket to inhibit viral uncoating [PMC, MDPI].

Other names

Poliovirus Type 2 (MEF-1 strain) antigenInactivated Poliovirus Vaccine Type 2IPV Type 2Lansing strain antigenPoliovirus type 2 antigen

Stimulates the production of neutralizing IgG antibodies that bind to the viral capsid and prevent host cell entry via the CD155 receptor; also serves as a target for capsid-binding antivirals that inhibit viral uncoating.