Production and characterization of a monoclonal antibody against recombinant thermolabile hemolysin and its application to screen for Vibrio parahaemolyticus contamination in raw seafood

• Published in: Food control Vol. 23; no. 1; pp. 171 - 176
• Main Authors: Sakata, Junko, Kawatsu, Kentaro, Kawahara, Ryuji, Kanki, Masashi, Iwasaki, Tadashi, Kumeda, Yuko, Kodama, Hiroshi
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-01-2012
• Subjects: Contamination; ELISA; enzyme-linked immunosorbent assay; monoclonal antibodies; Monoclonal antibody; raw seafoods; recombinant antibodies; Screening method; Seafood; Thermolabile hemolysin; Vibrio parahaemolyticus; Vibrio parahaemolyticus; Seafood; Screening method; Thermolabile hemolysin; Monoclonal antibody; ELISA
• ISSN: 0956-7135; 1873-7129
• DOI: 10.1016/j.foodcont.2011.07.005

Thermolabile hemolysin gene (tlh) is regarded as a species-specific marker for Vibrio parahaemolyticus. To assess the utility of the tlh gene product, thermolabile hemolysin (TLH), as a marker to screen for V. parahaemolyticus-contamination in raw seafood, we generated a monoclonal antibody (MAb) against recombinant TLH and established with an enzyme-linked immunosorbent assay using the MAb (TLH-ELISA). TLH-ELISA testing of broth cultures for 78 V. parahaemolyticus strains showed positive results all around. In contrast, most broth cultures of 53 non-V. parahaemolyticus species tested yielded negative results.
We devised a screening method using TLH-ELISA to check for low-level contamination of V. parahaemolyticus in raw seafood within 24 h and evaluated its ability. In testing of V. parahaemolyticus-spiked raw seafood, results suggested that our screening method can detect 100 most-probable-number (MPN) of V. parahaemolyticus/g. Further, on testing 119 commercial raw seafood samples with our screening method, 117 samples were determined to contain less than 100 MPN of V. parahaemolyticus/g. All of the 117 samples were also estimated by the MPN method to contain less than 100 MPN of V. parahaemolyticus/g. Taken together, these results suggest that our screening method using TLH-ELISA is useful to check for low-level (<100 MPN/g) of V. parahaemolyticus in raw seafood.
► We generated a monoclonal antibody against recombinant thermolabile hemolysin (TLH). ► The ELISA (TLH-ELISA) using this monoclonal antibody was established. ► TLH-ELISA demonstrated that all V. parahaemolyticus strains tested produce TLH. ► The screening method using TLH-ELISA was devised to ensure food safety. ► The method could check for contamination of the bacterium in seafood within 24 h.