Tick-borne encephalitis virus envelope protein (TBEV E protein) (TBEV E protein)

The Tick-borne encephalitis virus (TBEV) envelope (E) protein is the primary surface glycoprotein of the virus and is essential for its infectivity and structural integrity (UniProt P08486). It functions as a class II viral fusion protein, mediating both the attachment to host cell receptors and the subsequent pH-dependent membrane fusion within endosomes (Heinz & Stiasny, 2014). As the most prominent protein on the virion surface, the E protein is the principal target for the host's immune response, specifically for neutralizing antibodies. Vaccines such as FSME-IMMUN and Encepur are designed to present the E protein in its native conformation to induce a broad repertoire of polyclonal antibodies (Pulkkinen et al., 2022). These vaccine-induced antibodies prevent infection by sterically hindering receptor binding or by blocking the conformational changes required for fusion. Monitoring the titers of these antibodies, particularly through neutralization assays, serves as a key biomarker for vaccine efficacy and long-term immunity (WHO, 2011). Understanding the antigenic structure of the E protein is also vital for addressing potential challenges such as antibody-dependent enhancement or cross-reactivity with other flaviviruses (Stiasny et al., 2006).

Other names

Envelope glycoprotein ETBEV ETBEV envelope proteinTick-borne encephalitis virus E protein

Neutralization of viral entry by binding to the E protein, which sterically hinders receptor attachment and prevents the pH-dependent conformational change required for membrane fusion within host endosomes.