Poliovirus type 2 inactivated virion antigens (IPV Type 2)

Poliovirus type 2 inactivated virion antigens are the structural components of the poliovirus (typically the MEF-1 strain) that have been rendered non-infectious through chemical inactivation, usually with formaldehyde [4, 10]. These antigens consist of the viral capsid proteins VP1, VP2, VP3, and VP4, which maintain their three-dimensional "D-antigen" structure to ensure high immunogenicity [1, 5]. As a primary component of the Inactivated Poliovirus Vaccine (IPV), these antigens are designed to stimulate the host's immune system to produce specific neutralizing antibodies without the risk of causing the disease itself [6, 8]. These antibodies circulate in the blood and can neutralize wild-type or vaccine-derived poliovirus type 2 by blocking its ability to bind to the CD155 receptor on human cells [1, 12]. The inclusion of type 2 antigens is particularly critical in the current global eradication phase, as wild poliovirus type 2 has been eradicated, but vaccine-derived strains continue to pose a threat [11, 15]. Consequently, transitioning from oral vaccines to inactivated antigens is a key strategy to eliminate the risk of vaccine-associated paralytic polio [6, 14]. In addition to their role in vaccines, these capsid proteins are also the target of experimental antiviral agents like pocapavir, which bind to the hydrophobic pocket of the capsid to prevent viral uncoating [13]. Monitoring the potency of these antigens is essential for vaccine efficacy, often measured by the presence of D-antigen units in the final product [10].

Other names

Inactivated Poliovirus Type 2Poliovirus Type 2 (MEF-1 strain) antigenSalk vaccine type 2 componentPV-2 inactivated antigenD-antigen of Poliovirus Type 2

Induction of humoral immunity through the production of neutralizing antibodies against the Poliovirus type 2 capsid proteins, preventing viral attachment and entry into host cells.