Inhibition of rotavirus in vitro transcription by optimal concentrations of monoclonal antibodies specific for rotavirus VP6

The 1 Ohio State University, Department of Medical Microbiology and Immunology, 5072 Graves Hall, 333 W. 10th Avenue, Columbus, Ohio 43210 and 2 James N. Gamble Institute of Medical Research, 2141 Auburn Avenue, Cincinnati, Ohio 45219, U.S.A. Three monoclonal antibodies (MAbs) obtained from inoculation of mice with either a serotype 1 human rotavirus or rotavirus SA11 (serotype 3) inhibited the in vitro transcription of rotavirus SA11. Two of the MAbs exhibited a biphasic inhibitory response. Removal of antibody from MAb preparations by adsorption with Sepharose-Protein G reduced the inhibitory activity completely for all three MAb preparations. Analysis by radioimmunoprecipitation and Western blotting indicated that all three MAbs reacted with VP6. All MAbs also reacted with four group A rotavirus serotypes by ELISA, but did not cross-react with reovirus type 1, poliovirus type 2 or MA-104 cell lysates. Transcription of four rotavirus serotypes as well as epizootic diarrhoea of infant mice rotavirus was inhibited when tested with two of the MAbs. Transcription of both purified single-shelled virus and purified heat-activated double-shelled SA11 rotavirus was inhibited by purified MAb. Our results indicate that these MAbs can be used effectively to study the events associated with rotavirus transcription. Received 13 March 1992; accepted 7 July 1992.