Use of monoclonal antibodies for the serological differentiation of wheat and oat furoviruses

Twenty monoclonal antibodies (MAbs) to Chinese wheat mosaic virus (CWMV) were produced by immunizing BALB/c mice with purified CWMV. These MAbs and polyclonal antisera against CWMV and soil-borne wheat mosaic virus Oklahoma isolate (SBWMV-Ok1) were used to differentiate the wheat and oat furoviruses, CWMV, SBWMV, oat golden stripe virus (OGSV) and European wheat mosaic virus (EWMV), Enzyme-linked immunosorbent assays and Western blotting showed that the dominant epitope(s) of CWMV was shared partially with OGSV whereas those of SBWMV were shared with CWMV, OGSV and EWMV in varying degrees. When CWMV virions were briefly digested with trypsin, coat protein fragments of about 12, 10 and 8 kDa were produced and these reacted with the polyclonal antisera and some MAbs, indicating that they contained dominant epitopes of CWM V and SBWMV. Computer analysis of the coat protein sequences suggested that the epitope shared between CWMV and OGSV was located at amino acids 35-40, whereas the dominant epitopes of SBWMV, which were shared with CWMV, EWMV and OGSV, were in the C terminal half of the coat protein.