CONICET | Buscador de Institutos y Recursos Humanos

Ver pagina 245 del adjunto Superantigens(SAgs) interact with TCRβ and MHC-II molecules promoting a deregulated and nonspecific immune response which can produce toxic shock syndrome, immunosuppression that favors the spread of the pathogen and sepsis. SAg presence in food, especially dairy products, is related to food poisoning and it can be lethal in a couple of hours. Consequently, it is highly important to detect Sags rapidly in any biological matrix. Currently, standard food microbiological testing does not include the detection of bacterial enterotoxins, even knowing that they are heat-stable and can resist pasteurization. Classical methods such as ELISA or Western blotting can detect SAgs, but they do not provide real-time information. In order to find a rapid, sensitive and specific method for the detection of SAgs, we developed an optimized assay using Surface Plasmon Resonance(SPR) methodology in a Biacore T100 instrument. The response enhancement is based on a ?sandwich? approach using polyclonal specific antibodies. The first antibody, previously immobilized on a sensor chip, captures the toxin in a liquid sample and, subsequently, a secondary antibody is run in solution enabling the corresponding signal amplification. We demonstrated that this novel method reaches a lower detection limit compared to other immunoassays. While ELISA is able to detect levels of 1.10-9M of SEG, our SPR approach can detect concentrations as low as 1.10-12M. The cutoff values found for each methodology were 0,02±0,02AU and 49±4RU, respectively. Both high sensitivity and real-time sample processing are the key features of this simple methodology that can be of potential use for the detection of enterotoxins in food industries, laboratories and regulatory agencies.