Anti-algal toxin antibodies


The shellfish sector represents a significant portion of the US $78 billion (first sale value, 2002) global fish and fish products market, with aquaculture production far exceeding capture production and growing steadily at approximately 6% per annum. Molluscs account for 85% of the total world marine or brackish water shellfish production, with an estimated value of US $11.5 billion in 2003. The biggest threat facing the molluscan shellfish industry is the sporadic and often unpredictable occurrence of substances that are toxic to human in the phytoplankton feedstock. Toxins accumulate in the shellfish tissue and pose a serious risk to human health. Rapid and early detection of these toxins would significantly reduce the economic consequences for shellfish producers of a toxic episode. Antibody-based immunoassay procedures offer the possibility of rapid on-site detection of toxins in shellfish and water samples and also rapid high-throughput screening of large sample numbers. A number of highly sensitive anti-algal toxin antibodies, which have been shown to be suitable for both rapid and high-throughput assay systems for the detection of algal toxins, have been produced and are now available in unlimited quantities.

Background

The diarrhetic shellfish poisoning (DSP) toxins, okadaic acid acid and its analogues, and the amnesic shellfish poisoning (ASP) toxin, domoic acid, are among the most widely occurring toxin groups to occur in shellfish worldwide. The current testing protocol used routinely to screen shellfish for the presence of DSP toxins is either the IFREMER modification of the Yasumoto mouse bioassay involving intra-peritoneal injection of shellfish extracts and monitoring the time to death or a HPLC method and domoic acid is measured by HPLC. Both these methods are inappropriate for high throughput screening or on-site testing and are not sufficiently sensitive to enable toxin detection in environmental samples. Immunoassay methods have been described for these toxins and some are commercially available, but they tend to be based on limited supplies of polyclonal antibodies that will limit the lifespan of these products.

Technology Description

An anti-domoic acid sheep scFv (recombinant single chain antibody variable region fragment) is available, that is highly stable, can be conjugated, and can detect down to 500 pg/ml domoic acid in microtitre plate format and to 100 ng/ml in high-throughput surface plasmon resonance (SPR)-based biosensor format.

Anti-domoic acid chicken scFv and mouse monoclonal antibodies are also available with detection limits of approximately 500 ng/ml domoic acid. The monoclonal antibody has been shown to be suitable for lateral flow format.

A panel of 8 highly sensitive mouse monoclonal anti-okadaic antibodies are available. These antibodies have been shown to be able to detect down to 1 ng/ml okadaic acid in microtitre plate immunoassay format and to 10 ng/ml in high-throughput surface plasmon resonance (SPR)-based biosensor format. The antibodies cross-react almost 80% with the major okadaic acid analogue, DTX 1. Cross-reactivity study with DTX-2 is pending.

Principal Investigator:

Dr. Marian Kane NDC, NUI, Galway.

Competitive Advantage

The scFvs are expressed by stable recombinant E. coli clones and can be produced quickly and cheaply in unlimited supplies. The monoclonals are produced by stable monoclonals and again are available in unlimited supplies. All antibodies have desirable cross-reactivity profiles and sensitivities.

Type of Business Sought

Partners for further development and validation of different assay formats using these antibodies sought. The antibodies can also be purchased directly.

Contacts
Dr. Ruairi Friel,
Commercialisation Executive, TTO
Ruairi.Friel@nuigalway.ie
Tel: +353 (0)91 495826

Dr. Maura Glennon Enterprise Ireland, Biotechnology Commercialisation Directorate (EI Bio), NUI, Galway.
Phone: +353-91 492093, Fax: +353-91-586570
Maura.Glennon@enterprise-ireland.com

NUI, Galway is the owner of all IP. EI Bio works in partnership with NUI, Galway to commercialise the technology.

EI Bio is building the biotechnology sector through the strategic commercialisation of research in Ireland