Natural Adjuvants to Enhance Efficacy of Viral Vaccines for Mariculture

Marine aquaculture production now exceeds 20 million metric tons annually (FAO 2010) but viral diseases are still a major threat to the expansion of sustainable mariculture systems (National Marine Fisheries Service 2007). Pathogenic viruses continue to devastate many fish and shellfish operations every year (ICES Mariculture Committee 2004, Lightner 2011). To date, vaccines against aquatic animal viruses have generally provided poor protection, are too expensive, and/or must be injected intramuscularly (e.g., DNA vaccines). In response, we will expand and intensify development of innovative biological adjuvant systems initiated in our Phase I trials. We discovered that unique natural marine and terrestrial micro-structures bound to viral antigens can be delivered to gills and mucosal surfaces of salmon to boost specific immune responses against a viral pathogen. We use a nanotechnology-based dynamic light scattering laser instrument to verify attachment of viral antigens or DNA vaccines. Interferon-associated genes and specific antibody titers will be measured by quantitative PCR, ELISA, and virus neutralization tests. Needle-less, immersion immunizations with test formulations will be assessed in fish for safety and efficacy. Multiple, additional in vivo pathogen challenges will be conducted to evaluate new prototype vaccines for relative efficacy and commercialization potential in Phase III field trials.