Submitted to: Veterinary Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 23, 1995
Publication Date: N/A
Interpretive Summary: Pasteurella multocida is a bacterium that causes diseases in a wide variety of domesticated and wild animals. The bacterium produces a capsule that interferes with serological reactions and host defense mechanisms. This study describes the use of an enzyme, chondroitinase, to remove the capsule from Pasteurella multocida. The findings of this study will benefit diagnostic laboratories by providing an improved test for serological classification of Pasteurella multocida. Additionally, the use of chondroitinase in serologic tests will result in improved methods for veterinary clinicians and scientists to measure specific serologic responses of animals vaccinated with Pasteurella multocida.
Capsules of Pasteurella multocida serogroups A, D and F contain mucopolysaccharides which block antigenic determinants and prevent phagocytosis. In this study, capsules of serogroup A, D and F strains of P. multocida were depolymerized by enzyme treatment. Capsule depolymerization of serogroup D and F strains with chondroitinase increased indirect hemagglutination (IHA) test titers and enhanced phagocytosis by swine neutrophils. Capsule depolymerization of serogroup A strains with hyaluronidase increased IHA titers, but depolymerization with chondroitinase did not. When serogroup A strains were treated with a combination of chondroitinase and hyaluronidase, IHA test titers were lower than titers of the same strains treated with hyaluronidase alone. Combined enzyme treatment of serogroup D strains resulted in IHA test titers similar to those of chondroitinase treatment alone.