Characterization of Piscirickettsia salmonis membrane vesicles and their use as a vaccine for aquaculture
Appears in the following Collection
- Farmasøytisk institutt 
AbstractThe results presented in this thesis describe the investigation of Piscirickettsia salmonis derived membrane vesicles (MVs) as a vaccine candidate against salmonid rickettsial septicemia. MVs are small spherical structures known to contain a variety of bacterial components, including proteins, LPS, DNA and RNA, which makes the vesicles similar to their mother cell in many aspects. Comparative characterization of MVs from three different isolates of the bacterium revealed several strain specific differences, both in vivo and in vitro. When used for immunization in an adult zebrafish model the vesicles induced a protective response against P. salmonis. Incorporation of chitosan as an adjuvant, by MV encapsulation, did furthermore enhance the protective effect of the vesicles in adult zebrafish. Histological analysis indicated a reduced bacterial load upon challenge in the MV immunized group, and the RNA expression of several immune related genes altered, including mpeg1.1, tnfα, il1b, il10 and il6. MVs induced the secretion of IgM upon immunization, suggesting an immunogenic effect of the vesicles. Taken together, the data indicate a vaccine potential of MVs against SRS.
List of papers
|Paper I: Comparative analysis of membrane vesicles from three Piscirickettsia salmonis isolates reveals differences in vesicle characteristics. Tandberg JI, Lagos LX, Langlete P, Berger E, Rishovd AL, Roos N, Varkey D, Paulsen IT, Winther-Larsen HC. PLoS One, 2016 Oct 20; 11(10):e0165099. The article is included in the thesis. Also available at http://urn.nb.no/URN:NBN:no-63032|
|Paper II: Membrane vesicles from Piscirickettsia salmonis induce protective immunity and reduce development of salmonid rickettsial septicemia in an adult zebrafish model. Tandberg JI, Oliver C, Lagos LX, Gaarder M, Yáñez A, Ropstad E, Winther-Larsen HC. Fish and Shellfish Immunology, 2017 Jun 6; pii: S1050-4648(17)30336-4. The article is included in the thesis. Also available at http://urn.nb.no/URN:NBN:no-62950|
|Paper III: Use of chitosan coated membrane vesicles for immunization against salmonid rickettsial septicemia in an adult zebrafish model. Tandberg JI, Lagos LX, Ropstad E, Smistad G, Hiorth M, Winther-Larsen HC. Manuscript. To be published. The paper is not available in DUO awaiting publishing.|