Oral vaccine delivery for control of Tilapia Lake Virus (TiLV)

Title: Oral vaccine delivery for control of Tilapia Lake Virus (TiLV)USDA Phase I application Due October 22 2020.Topic Area 8.7 - AquacultureBudget: Total $100000(NuLode $66667; UAZ $33333)AbstractTilapia 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 worldwideand the emergence of this pathogen already in 16 countries is an indication that efforts should beintensified to provide an effective biocontrol methodology. There have already been three outbreaks ofTiLVD in the US.During the Phase I research we will perform a bioinformatics study of all availablegenomes of this negative sense RNA virus in order to determine the most conserved regions of criticalproteins. Since this is an RNA virus and known to mutate the bioinformatics study will be critical inselection of regions for production of a subunit vaccine based on recombinant peptides. We will use theprotein from segment 8 as our first potential vaccine target. We will also clone three of the mostconserved peptide regions identified in the bioinformatics study into yeast (single peptide containingyeast) to be used as an oral vaccine in rapid testng. The transgenic yeast containing the segment 8protein will be induced to produce the recombinant protein harvested and lysed by cavitation andfreeze dried. The freeze dried yeast will be encapsulated in the proprietary MSPâ„¢ system(Matrix/Scaffold/Payload) with an oral immunostimulator derived from Lactobacillus for a formulationsuitable to oral delivery to tilapia. During Phase I we will deliver the vaccine both orally and by injectioninto tilapia (versus control) and look for stimulation of specific antibodies against TiLV upregulation ofimmune related genes and determine by histology if any unexpected damage is induced by thisapproach. A successful Phase I will demonstrate a robust oral stimulation of an immune response intilapia and set the stage for an expanded study in Phase II.