Derivation of neutralizing monoclonal antibodies to human rotaviruses and evidence that an immunodominant neutralization site is shared between serotypes 1 and 3.

Neutralizing monoclonal antibodies were derived to human rotaviruses RV-4 (serotype 1), RV-5 (serotype 2), and ST-3 (serotype 4). By enzyme immunoassay and fluorescent focus neutralization, eight of the antibodies appeared to be specific for the immunizing serotype, and so have potential as reagents for rotavirus serotyping by enzyme immunoassay. Seven of these were shown by Western blotting, enzyme immunoassay for antibody additivity, and reaction with rotavirus reassortants, to be directed against the major outer capsid glycoprotein. The remaining serotype-specific antibody immunoprecipitated the 84-kD outer capsid protein. One antibody reacted with all serotype 1 and 3 rotaviruses but not with serotypes 2 or 4. When tested with virus mutants, this antibody recognized an immunodominant determinant of neutralization shared between serotypes 1 and 3 on the major outer shell glycoprotein. Our results suggest that two outer capsid proteins possess determinants of neutralization, and that viruses of different serotypes may share immunodominant neutralization sites.