SBIR-STTR Award

Tilapia lake virus (TiLV) is an emerging viral pathogen of farmed tilapine fish such as nile tilapia (Oreochromis niloticus) that is already impacting global aquaculture and could have a significant impacton US aquaculture in the near future. Tilapia are the second most important farmed finfish worldwide and the emergence of this pathogen already in 16 countries is an indication that efforts should be intensified to provide an effective biocontrol methodology. There have already been three outbreaks of TiLVD in the US. During the Phase I research we will perform a bioinformatics study of all available genomes of this negative sense RNA virus in order to determine the most conserved regions of critical proteins. Since this is an RNA virus and known to mutate the bioinformatics study will be critical in selection of regions for production of a subunit vaccine based on recombinant peptides. We will use the protein from segment 8 as our first potential vaccine target. We will also clone three of the most conserved peptide regions identified in the bioinformatics study into yeast (single peptide containing yeast) to be used as an oral vaccine in rapid testing. The transgenic yeast containing the segment 8protein will be induced to produce the recombinant protein harvested and lysed by cavitation and freeze dried. The freeze dried yeast will be encapsulated in the proprietary MSP™ system (Matrix/Scaffold/Payload) with an oral immune stimulator derived from Lactobacillus for a formulation suitable to oral delivery to tilapia. During Phase I we will deliver the vaccine both orally and by injection into tilapia (versus control) and look for stimulation of specific antibodies against TiLV up regulation of immune related genes and determine by histology if any unexpected damage is induced by this approach. A successful Phase I will demonstrate a robust oral stimulation of an immune response in tilapia and set the stage for an expanded study in Phase II.