Enterovirus A71 and Coxsackievirus A16 capsid proteins (EV-A71/CVA16 capsid antigens)

Enterovirus A71 (EV-A71) and Coxsackievirus A16 (CVA16) are the primary causative agents of Hand, Foot, and Mouth Disease (HFMD), a common pediatric illness (CDC, 2023). The capsid of these viruses is composed of four structural proteins: VP1, VP2, VP3, and VP4, which assemble to form an icosahedral shell (UniProt, 2024). These proteins are critical for protecting the viral RNA genome and recognizing host cell receptors, such as Scavenger Receptor Class B Member 2 (SCARB2) and P-selectin Glycoprotein Ligand-1 (PSGL-1), to facilitate viral entry (PubMed, PMID: 25135936). Because the capsid proteins are the most exposed parts of the virus, they serve as the primary antigens for the host's immune system and are the focus of vaccine development (WHO, 2017). Therapeutic strategies primarily focus on inactivated whole-virus vaccines or recombinant virus-like particles (VLPs) that elicit neutralizing antibodies (PubMed, PMID: 31401191). Additionally, small-molecule capsid binders, such as V-073, are being explored to inhibit the viral uncoating process by binding to the hydrophobic pocket of the VP1 protein (PubMed, PMID: 22438551).

Other names

EV71/CVA16 antigensHand, foot, and mouth disease viral antigensVP1, VP2, VP3, and VP4 structural proteins

Vaccines elicit neutralizing antibodies that target the VP1-VP3 surface loops to prevent receptor binding and cell entry (PubMed, PMID: 31401191). Capsid binders occupy the hydrophobic pocket in VP1, preventing the conformational changes required for viral uncoating (PubMed, PMID: 22438551).