Vaccinia virus B5 protein (B5R) (B5R)

The Vaccinia virus B5 protein (B5R) is a critical 42 kDa type I transmembrane glycoprotein found on the outer membrane of the extracellular enveloped virus (EEV) particle (UniProt P04300). It plays a pivotal role in the viral life cycle by mediating the formation of EEV and facilitating actin-based motility, which is essential for efficient cell-to-cell spread and systemic dissemination within the host (PubMed: 18077716). Structurally, B5 contains four complement control protein (CCP) domains, which contribute to immune evasion by potentially modulating the host's complement system (PubMed: 10823891). As EEV is the primary form responsible for long-range viral spread, B5 is a major target for neutralizing antibodies and is a key antigen in smallpox and mpox vaccines like ACAM2000 and JYNNEOS. Therapeutic strategies targeting B5, such as monoclonal antibodies or vaccine-induced immunity, aim to block the release and spread of the virus, thereby limiting the severity of the infection (PubMed: 15596814).

Other names

B5R proteinEnvelope glycoprotein B542 kDa glycoproteinComplement control protein B5

Neutralization of the extracellular enveloped virus (EEV) form and inhibition of viral dissemination and cell-to-cell spread.