Orthopoxvirus structural and envelope antigen (OPV antigen) (OPV antigen)

Orthopoxvirus structural and envelope antigens are a diverse group of proteins essential for the viral life cycle, including attachment, entry, and egress. These antigens are found on the two infectious forms of the virus: the Mature Virion (MV) and the Extracellular Virion (EV). Key MV antigens such as L1, A27, and H3 facilitate host cell binding and fusion, while EV-specific antigens like A33 and B5 are critical for cell-to-cell spread and immune evasion (Hooper et al., 2004; Moss, 2016). These proteins are the primary targets for neutralizing antibodies induced by vaccines like JYNNEOS and ACAM2000, which provide protection against smallpox and mpox (CDC, 2024). Additionally, the envelope wrapping protein VP37, encoded by the F13L gene, is the specific target of the antiviral drug tecovirimat, which prevents the dissemination of the virus by blocking EV formation (Grosenbach et al., 2018). Therapeutic use of Vaccinia Immune Globulin (VIGIV) also relies on antibodies directed against these surface antigens to provide passive immunity. Monitoring these antigens and their corresponding antibodies is vital for assessing vaccine efficacy and the emergence of drug-resistant viral strains. These antigens are highly conserved across the Orthopoxvirus genus, allowing for cross-protective immunity and broad-spectrum antiviral activity.

Other names

Poxvirus surface proteinOrthopoxvirus membrane proteinOrthopoxvirus virion proteinOrthopoxvirus envelope protein

Inhibition of viral envelope wrapping and egress by targeting the VP37 protein, neutralization of virions by antibodies, and induction of active immunity through vaccine-mediated antigen presentation.