Tumamao, J.Q. and Bowles, R.E. and van den Bosch, H. and Klassen, H.B.L.M. and Fenwick, B.W. and Blackall, P.J. (2003) An evaluation of the role of antibodies to Actinobacillus pleuropneumoniae serovar 1 and 15 in the protection provided by sub-unit and live streptomycin-dependent pleuropneumonia vaccines. Australian Veterinary Journal, 82 (12). pp. 773-780.
Article Link(s): http://dx.doi.org/10.1111/j.1751-0813.2004.tb13248...
Publisher URL: http://www3.interscience.wiley.com/cgi-bin/home
Objective To evaluate the serological response of pigs receiving either the Porcilis APP vaccine or a modified live vaccine based on a streptomycin-dependent (SD) strain of Actinobacillus pleuropneumoniae, and then challenged with an Australian isolate of A pleuropneumoniae of either serovar 1 or 15 as a means of understanding the protection provided by both vaccines against serovar 1 but not against serovar 15.
Design The serological tests evaluated were serovar-specific polysaccharide ELISA tests (for serovar 1 and 15), ELISA tests for antibodies to three A pleuropneumoniae toxins (ApxI, ApxII and ApxIII) as well as to a 42 kDa outer membrane protein (OMP), a haemolysin neutralisation (HN) assay and immunoblotting. The tests were used to detect antibodies in vaccinated pigs that had been shown to be protected against serovar 1 but not serovar 15.
Results In the polysaccharide antigen ELISA assays, both vaccines resulted in a significant rise in the titre in the serovar 1 ELISA but not the serovar 15 ELISA. The Porcilis APP vaccinated pigs showed a significant response in the ApxI, ApxIII and 42 kDa OMP ELISA. In the ApxII ELISA, all pigs tested (ie the Porcilis APP vaccinates and the controls) were positive on entry to the trial. In the HN assay, the Porcilis APP vaccinated pigs showed a significant response after one dose while the SD vaccinated pigs required two doses of vaccine before a marked rise in titre was induced. Immunoblotting revealed that neither vaccine generated antibodies that recognised the ApxIII produced by serovar 15.
Conclusions The failure of these vaccines to provide protection against serovar 15 may be due to novel virulence factors possessed by serovar 15, significant differences between the ApxIII toxin of serovar 15 and those present in the Porcilis APP vaccine and the live vaccine or failure to induce antibodies to the serovar 15 specific polysaccharide.
|Corporate Creators:||Animal Science|
|Additional Information:||Author version © Queensland Department of Primary Industries and Fisheries. Reproduced in accordance with the copyright policy of the publisher. © Blackwell Publishing. Access to published version may be available via Publisher’s website.|
|Keywords:||Actinobacillus pleuropneumoniae; serology; ELISA.|
|Subjects:||Veterinary medicine > Diseases of special classes of animals > Swine|
Veterinary medicine > Veterinary bacteriology
|Deposited On:||05 Aug 2004|
|Last Modified:||10 Sep 2010 03:38|
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