- Volume 28 Issue 3
Previously, we had reported that some Miamiensis avidus, a major pathogen of scuticociliatosis in cultured olive flounder, strongly agglutinated by flounder immune sera could escape from the agglutinated mass within a few hours. In the present study, we observed that M. avidus not only escaped from the agglutinated mass but also conducted division(s) before shedding its old covering. Furthermore, ciliates that survived the antibody-dependent complement killing (ADCK) assay were not killed even when re-exposed to a freshly prepared ADCK assay. This result suggests that the liberated ciliates from the ADCK assay might change not only their i-antigen types but also the epitopes of major surface antigens, which debilitate antibody-mediated complement killing ability.
Miamiensis avidus;Agglutination;Antibody-dependent complement killing;Division;Survival
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- Iglesias, R., Parama, A., Alvarez, M.F., Leiro, J., Fernandez, J. and Sanmartin, M.L.: Philasterides dicentrarchi (Ciliophora, Scuticociliatida) as the causative agent of scuticociliatosis in farmed turbot Scophthalmus maximus in Galicia (NW Spain). Dis. Aquat. Org., 46: 47-55, 2001. https://doi.org/10.3354/dao046047
- Iglesias, R., Parama, A., Alvarez, M.F., Leiro, J., Ubeira, F.M. and Sanmartin, M.L.: Philasterides dicentrarchi (Ciliophora: Scuticociliatida) expresses surface immobilization antigens that probably induce protective immune responses in turbot. Parasitol., 126: 125-134, 2003. https://doi.org/10.1017/S0031182002002688
- Kim, S.M., Cho, J.B., Kim, S.K., Nam, Y.K. and Kim, K.H.: Occurrence of scuticociliatosis in olive flounder Paralichthys olivaceus by Philasterides dicentrarchi (Ciliophora: Scuticociitida). Dis. Aquat. Org., 62: 233-238, 2004. https://doi.org/10.3354/dao062233
- Lee, E.H. and Kim, K.H.: Can the surface immobilization antigens of Philasterides dicentrarchi (Ciliophora: Scuticociliatida) be used as target antigens to develop vaccines in cultured fish? Fish Shellfish Immunol., 24: 142-146, 2008. https://doi.org/10.1016/j.fsi.2007.08.004
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- Simon, M.C. and Schmidt, H.J.: Antigenic variation in ciliates: Antigen structure, function, expression. J. Eukaryot. Microbiol., 54: 1-7, 2007. https://doi.org/10.1111/j.1550-7408.2006.00226.x
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Grant : Development of Fish Vaccines and Human Resource Training
Supported by : Ministry of Oceans and Fisheries