Complementing nuclear techniques with DNA vaccine technologies for improving animal health

The use of nuclear methods can enhance several features of DNA vaccines in protecting livestock against pathogens. While DNA vaccines already have several advantages over their traditional predecessors (e.g. cheap production, stability over a wide range of temperature, amenability to genetic manipulation, and no risk of reversion to pathogenicity), conventional gene delivery systems make immunization of livestock and aquaculture populations tedious. For this reason, we are developing radiation-synthesized intelligent delivery systems for DNA vaccines. We encapsulated a reporter construct pCMV center dot SPORT-beta-gal in radiation-synthesized kappa-carrageenan-polyvinylpyrrolidone microspheres IP20 (for stomach release) and IP18 (for intestinal release). The DNA-loaded polymers were orally administered to Oreochromis niloticus (black Nile tilapia), and whole organs were stained with X-gal to observe beta-galactosidase activity. Intense staining was observed in the stomach regions with IP20, while minimal staining was observed with IP18. The gills, in contrast, did not express beta-galactosidase activity. Our results show evidence of the successful gene delivery capabilities of radiation-synthesized microspheres.