Trial of toxicity of Yersinia ruckeri membrane vesicles as potential vaccine candidate
Fish farming is a fast growing industry; it is an important source for proteins and the production rates will continue to grow in line with the growth of the world population. The increased fish production comes, however, with problems such as the development and the spread of diseases. Diseases caused by intracellular bacteria are especially hard to treat and prevent. The long-term use of antibiotics should be avoided, due to the high possibility of development of antibiotic resistances. Therefore is the development of vaccines an important preventive measurement.
One intracellular bacterium that is causing problems in fish farms is Yersinia ruckeri (Y. ruckeri). Y. ruckeri is the causative agent of the red mouth disease, or yersioniosis, in salmonids and rainbow trout. The endemic red mouth disease leads to the formation of inner and outer hemorrhages, which leads to suffering of the fish and can result in a high mortality rates (Tobback et al., 2007).
Y. ruckeri produces membrane vesicles (MVs) which are small vesicles of approximately 20-250 nm in diameter. MVs contain membrane proteins, lipids, toxins, DNA and RNA and are usually secreted by the bacterium for biofilm production, pathogenesis or cell communication. MVs have increasingly been in focus of vaccination studies, due to their shown ability to induce immune responses (Toyofuku, Nomura and Eberl, 2019). This study will evaluate the possible use of MVs as targeted vaccine against Y. ruckeri infection. For this, the zebrafish model will be used. First, we need to evaluate the potential toxicity of the MVs in the fish. The fish will be exposed to different concentrations of the MVs isolated from Y.ruckeri. The MV toxicity will be evaluated by IP injection. The effect of the injected MVs to the immune system of fish will be evaluated and potential differences in response to the respective doses will be assessed. The amount of 160 fish for this trial is the minimal needed amount in order to be able to evaluate the effect of the MVs in a statistically relevant fashion. The fish will be monitored daily and any signs of abnormal behavior will lead to euthanasia of the fish to prevent it from suffering.
E. Tobback, A. Decostere, K. Hermans, F. Haesebrouck, K. Chiers. Yersinia ruckeri infections in salmonid fish; Journal of Fish Diseases 2007, 30, 257–268.
M. Toyofuku, N. Nomura and L. Eberl. Types and origins of bacterial membrane vesicles; Nature Reviews Microbiology 2019, 17, 13–24.
One intracellular bacterium that is causing problems in fish farms is Yersinia ruckeri (Y. ruckeri). Y. ruckeri is the causative agent of the red mouth disease, or yersioniosis, in salmonids and rainbow trout. The endemic red mouth disease leads to the formation of inner and outer hemorrhages, which leads to suffering of the fish and can result in a high mortality rates (Tobback et al., 2007).
Y. ruckeri produces membrane vesicles (MVs) which are small vesicles of approximately 20-250 nm in diameter. MVs contain membrane proteins, lipids, toxins, DNA and RNA and are usually secreted by the bacterium for biofilm production, pathogenesis or cell communication. MVs have increasingly been in focus of vaccination studies, due to their shown ability to induce immune responses (Toyofuku, Nomura and Eberl, 2019). This study will evaluate the possible use of MVs as targeted vaccine against Y. ruckeri infection. For this, the zebrafish model will be used. First, we need to evaluate the potential toxicity of the MVs in the fish. The fish will be exposed to different concentrations of the MVs isolated from Y.ruckeri. The MV toxicity will be evaluated by IP injection. The effect of the injected MVs to the immune system of fish will be evaluated and potential differences in response to the respective doses will be assessed. The amount of 160 fish for this trial is the minimal needed amount in order to be able to evaluate the effect of the MVs in a statistically relevant fashion. The fish will be monitored daily and any signs of abnormal behavior will lead to euthanasia of the fish to prevent it from suffering.
E. Tobback, A. Decostere, K. Hermans, F. Haesebrouck, K. Chiers. Yersinia ruckeri infections in salmonid fish; Journal of Fish Diseases 2007, 30, 257–268.
M. Toyofuku, N. Nomura and L. Eberl. Types and origins of bacterial membrane vesicles; Nature Reviews Microbiology 2019, 17, 13–24.