Molecular Approaches to Immunological Biosensors: Phage Displayed Antibodies for the Detection of Foodborne Pathogenic Bacteria

Abstract

Traditional methods for the detection of microbial food-borne pathogens require 3-7 days to obtain a result. The introduction of HACCP plans and the desire to hold raw meat products in inventory until test results are confirmed have increased the need for more rapid detection methods. Recently, a variety of rapid methods (8-48 hours) have been developed. Many of these rapid methods utilize antibody molecules to capture and detect food-borne pathogens. Thus, the development of these immunosensor methods depends on the availability of antibodies with sufficient specificity. Rapid detection of Listeria monocytogenes has been hampered by the lack of polyclonal serum or monoclonal antibodies that can specifically detect the organism at the species level. Recently, antibody phage display has been employed to isolate a single-chain antibody fragment specific for L. monocytogenes and this single-chain antibody is being used to develop immunosensors for the detection of L. monocytogenes in food. The techniques should be applicable to other foodborne and emerging pathogens.