Use of a 35.5 kDa cell membrane composition of Pasteurella multocida and an anti-idiotype antibody to induce protective immunity in leghorn chickens.

Using polyacrylamide gel electrophoresis and Western blot analysis, a 35.5 kDa cell membrane composition of Pasteurella multocida ATCC 11039 was identified as a dominant epitope of the bacterium. Mice inoculated with inactivated whole bacteria produce antisera primary reactive with the 35.5 kDa component (Pm35.5) in Western blot analysis. The outer membrane component was composed primarily of protein but did have lipopolysaccharide present at 133 micrograms mg-1 protein. In challenge trials (Trial 2), groups of white leghorn chickens vaccinated with Pm35.5 or an anti-idiotypic antibody (using Pm35.5 as the original antigen) had significant difference in mortality of 3.2% and 48.3%, respectively, when compared with unvaccinated controls (99%). Mortality in a group of chickens receiving a commercially available bacterin (9.2%) was higher but not significantly different from the mortality of the Pm35.5 vaccinated group (3.2%).