Edema disease in piglets is caused by
Shiga toxin 2e (Stx2e)-producing Escherichia coli. However, there is currently no available Stx2e-specific immunochromatographic test strip to differentiate Stx2e from other types of
Shiga toxin 2. In the present study, to develop an Stx2e-specific immunochromatographic test strip, we isolated nine different
monoclonal antibody-producing hybridoma clones from Stx2e
toxoid-immunized mice and confirmed that six
antibodies were A subunit-specific whereas three
antibodies were B subunit-specific. Only one A subunit-specific
monoclonal antibody (45B2) was cross-reactive with prototype Stx2 (Stx2a) at the same sensitivity, but the remaining eight
monoclonal antibodies were not. In immunochromatographic tests using the highly sensitive
antibodies, test strips using some combinations of
gold colloid-conjugated
monoclonal antibody with the B subunit-specific
monoclonal antibody on the membrane detected Stx2e, but not other types of
Shiga toxin 2. These test strips had the ability to detect Stx2e in the culture supernatant of clinically isolated Stx2e gene-positive strains, but not in those of Stx2e gene-negative strains. These results indicate that our test strip is practical for the specific detection of Stx2e to diagnose
swine edema disease.