Rotavirus A outer capsid protein VP7 and spike protein VP4 (RVA VP7/VP4)

Rotavirus A VP7 and VP4 are the two outer capsid proteins that constitute the primary targets for the host's neutralizing antibody response during infection (Crawford et al., 2017). VP7 is a 37-kDa glycoprotein that forms the virion's outer shell and defines the G-serotype, while VP4 is an 87-kDa spike protein that defines the P-serotype and mediates viral attachment and penetration into host cells (Desselberger, 2014; Settembre et al., 2011). The antigenic epitopes on these proteins are the specific sites recognized by B-cells and antibodies; for VP7, these are categorized into regions such as 7-1a, 7-1b, and 7-2, whereas VP4 epitopes are located on its cleaved subunits, VP8* and VP5* (Aoki et al., 2009). These epitopes are the functional targets for all current rotavirus vaccines, including Rotarix and RotaTeq, which aim to elicit protective immunity by preventing the virus from infecting enterocytes (Angel et al., 2007). Because rotaviruses undergo frequent genetic reassortment and antigenic drift, monitoring changes in these epitopes is crucial for assessing vaccine efficacy and the emergence of escape mutants (Patton, 2012). Consequently, these proteins are central to the development of next-generation vaccines and therapeutic monoclonal antibodies intended to provide broad protection against diverse rotavirus strains (Gentsch et al., 1992).

Other names

VP7 glycoproteinVP4 spike proteinG proteinP proteinRotavirus A antigenic epitopesRotavirus A antigenic determinants

Induction of neutralizing antibodies (primarily secretory IgA and serum IgG) that bind to specific epitopes on VP7 and VP4, thereby blocking viral attachment to host cell receptors and preventing membrane penetration into intestinal enterocytes.