A POLYCLONAL ANTISERUM AGAINST A RECOMBINANT VIRAL PROTEIN COMBINES SPECIFICITY WITH VERSATILITY

A polyclonal rabbit antiserum was obtained to the nucleoprotein of tom ato spotted wilt tospovirus expressed as a recombinant fusion protein in E. coli. In indirect plate trapping ELISA, the antiserum gave simil ar titres against purified TSWV nucleocapsids in native form, the fusi on protein and the carrier protein. The crude antiserum was also teste d by Western blotting, indirect plate trapping ELISA and immunogold el ectron microscopy of thin sections; purified immunoglobulins were test ed by DAS-ELISA. In all cases, with both glasshouse and field material , the antibodies had good detectability and specificity. By ELISA and Western blots against other tospoviruses, impatiens necrotic spot and groundnut bud necrosis viruses did not react but there was a reaction with groundnut ringspot virus, reflecting the nucleoprotein amino acid sequence similarity. These antibodies combine specificity to the targ et protein and versatility with regard to all the more important serol ogical techniques. There were no undesired reactions resulting from im munization using a complex virus purified from infected host material.