Monoclonal antibodies against Stx1B subunit of Escherichia coli O157:H7 distinguish the bacterium from other bacteria

Aims: The Shiga-like toxins (Stx) are critical virulence factors of enterohaemorrhagic Escherichia coli (EHEC). Stx1B subunit plays important roles in EHEC infection. This work aims to generate and characterize monoclonal antibodies (mAbs) against the Stx1B and to investigate their utility in discrimination ELISA. Methods and Results: Two newly identified mAbs (designated 2H8 and 1B10, respectively) against the Stx1B protein were prepared via hybridoma techniques. The immunoreactivity of both mAbs to the Stx1B protein was confirmed in ELISA and Western blot. Moreover, they differentiate EHEC from Salmonella enteritis, non-Stx1-producing E. coli, Mycobacterium tuberculosis, Listeria monocytogenes, Streptococcus agalactiae and Staphylococcus aureus. Conclusions: The anti-STx1B mAbs are valuable diagnostic reagents for distinguishing EHEC from other bacteria. Significance and Impact of the Study: This is the first report regarding the usage of anti-STx1B mAbs in discrimination ELISA. The established ELISA may have potential in clinical surveillance of EHEC infection.