Development of a DNA vaccine against Renibacterium salmoninarum in Atlantic salmon (Salmo salar)

by Simard, Nathalie C.

DNA-based immunization was investigated as a possible approach to prevent Renibactenum salmoninarum infection in Atlantic salmon (Salmo salar). Two DNA vaccine prototypes, pNCSV3 and pNCSV6, encoding a portion of R. salmoninarum p57 major protein antigen under the control of the simian virus 40 (SV40) late promoter and the cytomegalovirus (CMV) promoter respectively, were constructed. Transfection of chinook salmon embryonic (CHSE-214) cell cultures with either prototypes resulted in detectable transcriptional activity. lmmunocytochernical analysis revealed that authentic epitopes were conserved in the protein expressed by pNCSV6, however, no perceptible signal was obtained from pNCSV3. Efficiency of the DNA vaccines to protect Atlantic salmon was evaluated in a CO-habitation challenge. Microbiological examination of the kidneys revealed similar bacterial counts for both vaccinated and control groups indicating that the vaccinated fish where not protected from infection. Nonetheless, transcriptional activity in the fish apical musclewas detected for both prototypes 68 days following vaccination. I would like to thank my parents, Mariette and Guy, and my younger sibling Christine for their continuous encouragementand their belief in me. My recognition also goes to Lenora Fanjoy & family who have adopted me as one of their own. I am forever grateful for al1the warmth and happiness you have brought into my life. I would also like to thank my supervisor, Dr. William Lynch, and the other members of my supervisory committee, Dr. Steve Griffiths and Dr. Denise Clark, for their help and guidance. I would also like to acknowledge Roger Smith. Nancy MacAfee, Jana Olmstead. Sun Yong Lee, Jane Lovely, Lynn Hutchin, and Krista Melville for their technical assistance and expertise. A special thank you also goes to r.iy lab mates, Marcia Cook and Troy Barton, who have helped with sample processing and analysis. Last but not least, a special thank you to Debby Bani, Patricia Edwards and Todd Harper. three wonderful friends who always brighten my days. Thank you al1 for having made my stay at UN0 a mernorable one. Abstract ....................................................... ii