IMMUNOAFFINITY PURIFICATION OF BACULOVIRUS-EXPRESSED RUBELLA-VIRUS E1FOR DIAGNOSTIC PURPOSES

Three monoclonal antibodies, termed 4E10, 1E11:10, and 2D9:1, were gen erated against rubella virus. Immunoblot analysis with purified authen tic rubella virus or recombinant baculovirus-expressed rubella virus s tructural proteins E1, E2, and C demonstrated that they were directed against the E1 envelope glycoprotein of the rubella virus particle. By using the yeast Ty virus-like particle system, it was possible to map the binding site of 1E11:10 within amino acids 236 to 286 of the E1 p rotein and the binding sites of 2D9:1 and 4E10 outside this region. Im munoaffinity purification with these monoclonal antibodies made it evi dent that they are useful for obtaining large quantities of pure bacul ovirus-expressed rubella virus envelope protein E1. The diagnostic pot ential of this immunoaffinity-purified recombinant rubella virus E1 pr otein compared with that of authentic rubella virus is demonstrated.