TWENTY-SECOND ANNUAL EASTERN FISH HEALTH WORKSHOP ROYAL PAVILLION RESORT, ATLANTIC BEACH, NC MARCH 18 - 20, 1997 DNA-Mediated Vaccination in Channel Catfish Steven E. Poet and Victoria V. Burnley University of Georgia, College of Veterinary Medicine,Department of Medical Microbiology Athens, Georgia 30602 DNA-mediated vaccination is a new weapon in the battle against infectious diseases. The parameters responsible for effective genetic immunization in channel catfish have not been studied. The objectives of this project are to demonstrate the activity of mammalian promoter sequences in the channel catfish, and to evaluate the parameters controlling the magnitude of expression. Channel catfish ovary (CCO) cells were transfected with eukaryotic expression plasmid constructs containing either no gene, or a b-galactosidase reporter gene in order to demonstrate the activity of the mammalian cytomegalovirus (CMV) immediate-early enhancer/promoter in catfish cells in vitro. Enzyme activity was only observed in cells transfected with the CMV promoter/b-galactosidase gene plasmid construct. Channel catfish (Ictalurus punctatus) were injected intramuscularly with 50 ug of the CMV expression plasmid constructs containing either no gene or a b-galactosidase reporter gene. At 7 days post injection, the musculature surrounding the injection site, anterior kidney, posterior kidney, liver, spleen, gill, and intestine were processed for immunohistochemical analysis. In addition, flanking tissue at the injection site musculature was collected, lysed, and assayed for b-galactosidase activity. Positive-staining muscle bundles were observed in fish injected with the b-galactosidase gene. No staining was observed in control fish. In addition, enzyme activity was only observed in the muscle flanking the injection site of the fish inoculated with the b-galactosidase plasmid. Return to 22nd Annual Eastern Fish Health Workshop Return to Leetown Science Center Home Page