Rotavirus outer capsid spike protein VP4 VP8* domain (VP4 (VP8* domain))

The rotavirus outer capsid spike protein VP4 is cleaved by trypsin into two fragments, VP8* (N-terminal) and VP5* (C-terminal). VP8* forms the outermost globular head of the rotavirus spike and is responsible for primary attachment of rotavirus to host epithelial cells by binding specific cell surface glycans, including sialic acid (in animal strains) or histo-blood group antigens (in most human strains). This initial binding step is essential for viral entry and is a determinant of host range, tissue tropism, and cross-species transmission. VP8* is highly antigenic and elicits neutralizing antibodies; it is a key target for vaccine development and monoclonal antibody therapies. Antigenic diversity in VP8*, divided into multiple P genotypes, underlies differences in rotavirus epidemiology and can contribute to immune escape. The function of VP8* and the structure of its glycan-binding pocket have been resolved for several genotypes, revealing adaptation to host glycan polymorphism. No small-molecule drugs directly target VP8*, but it is commonly used as a subunit antigen in vaccine research and diagnostics. Safety concerns include high genetic diversity and the possibility of immune evasion.

Other names

Rotavirus VP4Rotavirus VP8*Outer capsid spike protein VP4Spike protein VP4VP4/VP8* antigens

For neutralizing antibodies: Block binding of VP8* to cell surface carbohydrates (sialic acid or histo-blood group antigens), preventing cell entry and fusion. Vaccination: Induce neutralizing antibody response targeting VP8*/VP4