Identification of VP7 serotypes of human rotaviruses by enzyme-linked immunosorbent assay and reverse transcription-polymerase chain reaction.

Serotype specificity of human rotaviruses in Taiwan remained unclear. This study has established three methods for identification of G serotypes, fluorescent focus neutralization test (FFN), enzyme-linked immunosorbent assay by incorporating VP7 (G) serotype-specific monoclonal antibodies (ELISA-MAb) and reverse transcription-polymerase chain reaction (RT-PCR). FFN is a reference standard test for determination of G serotype. RT-PCR and ELISA-MAb were used for serotyping of rotavirus isolates and appeared to be accurate and more sensitive than FFN. Nevertheless, for serotyping the rotaviruses present in clinical stool samples, ELISA-MAb was not satisfactory, only 65.5% of the 264 specimens could be serotyped. The sensitivity of serotype prediction by RT-PCR was 89.4%. When both ELISA-MAb and RT-PCR were taken into account, G serotype could be predicted for 93.2% of the specimens. Serotyping results were comparable with the RNA profiles. Rotaviruses with similar RNA electrophoretic pattern had the same serotype specificity. RNA patterns could be used as a reference for prediction of serotypes. Because ELISA is easy to perform and less expensive, it would be suggested as a screening test. RT-PCR could be used for samples which could not be serotyped by ELISA-MAb. Furthermore, RT-PCR is especially valuable when serotype-specific monoclonal antibodies are not available.