Characterization of α-hemolysin-specific monoclonal antibodies for detection in the culture supernatant of pathogenic <i>Escherichia coli</i> strains

α-Hemolysin (α-Hly) is produced by pathogenic Escherichia coli and is implicated in a variety of diseases. In the swine, enterotoxigenic E. coli (ETEC) and Shiga toxin-producing E. coli (STEC) strains cause post-weaning diarrhea and edema disease, respectively, and most of these strains are hemolytic. However, the role of α-Hly in ETEC and STEC infection is unclear. Here, we prepared α-Hly-specific monoclonal antibodies by immunizing animals with one-third of the carboxy end of recombinant α-Hly. The four α-Hly-specific antibodies obtained reacted with α-Hly in the culture supernatant of clinical isolates in enzyme-linked immunosorbent assay and western blot analysis. In addition, because these four monoclonal antibodies inhibited E. coli-induced hemolysis, these antibodies might be useful tools for investigating the significance of α-Hly in pathogenic strains.