Norovirus genogroup I genotype 1 major capsid protein (VP1 antigen) (Norovirus GI.1 VP1 antigen)

The Norovirus genogroup I genotype 1 (GI.1) antigen refers specifically to the major capsid protein VP1 that forms the outer shell of the GI.1 norovirus particle, including the Norwalk virus strain (prototype GI.1). VP1 is the principal target of the host immune response and elicits neutralizing antibodies, particularly directed against the surface-exposed P (protruding) domain. The P domain mediates binding to human histo-blood group antigens (HBGAs), which are essential for cell attachment and infection initiation. Structural studies show that VP1 exhibits conformational epitopes that can vary between strains, affecting both HBGA binding specificity and sensitivity to neutralizing antibodies. The VP1 antigen is the focus of various norovirus diagnostics, vaccine development efforts, and structural studies seeking to understand immune protection and viral evolution.

Other names

Norwalk virus capsid protein VP1Norovirus GI.1 capsid proteinNorovirus GI.1 antigenGI.1 VP1

Neutralization via blockade of HBGA (histo-blood group antigen) binding by antibodies, preventing viral attachment to host cells. Antibody binding to conformational epitopes on the VP1 P domain, disrupting cell entry. Vaccine candidates induce protective immunity by targeting VP1.