UBC Theses and Dissertations
Factors contributing to the maintenance and activation of corynebacterial pseudotuberculosis in the laboratory mouse Bruce, David Lorne
Corynebacterial pseudotuberculosis, a murine disease caused by Corynebacterium kutscheri, occasionally developed in numbers of the departmental strain of random-bred Swiss white mice 3 to 5 weeks following intraperitoneal injection of the Rauscher leukemia virus. Virulent C. kutscheri, extremely difficult to isolate from apparently healthy animals, was frequently cultured from the organs of animals presenting symptoms of the Rauscher disease without active pseudotuberculosis. Representative groups of the departmental strain showed uniformly high resistance to intravenous injection of virulent C. kutscheri in comparison to imported pathogen-free strains, yet succumbed to pseudotuberculosis in large numbers following cortisone treatment; therefore the entire colony was assumed to be latently infected by this organism. Two strains of C. kutscheri were isolated and compared to strains ATCC 15677 and ATCC 15678. The latter strain, a presumed non-pathogenic variant of the former, was compared by cell wall sugar and deoxyribonucleic acid base analysis to the pathogenic strain. It was not possible by these methods to find support for the variant hypothesis. Transfer of the latent state from the departmental strain to a pathogen free strain of mice was attempted by injection of homogenates of visceral organs, but transfer of latency was not successfully demonstrated. The sera of latently infected mice stimulated in vivo phagocytosis of C. kutscheri by mouse peritoneal macrophage, but it was not possible to demonstrate circulating C. kutscheri specific antibody in non-immunized animals. Immunized normal mice of all strains developed high titers of specific circulating antibody following injections of either heat killed C. kutscheri cells or virulent organisms in numbers too low to initiate infection. Circulating antibody was demonstrated by passive bacterial hemagglutination and by indirect fluorescent antibody staining. When immunization was attempted during early Rauscher disease, C. kutscheri antibody production was inhibited. Clearance studies with labeled C. kutscheri showed that the organism is cleared with exceptional rapidity by the reticuloendothelial system of latently infected mice, pathogen free mice and mice with early Rauscher disease. The clearance constant decreased slightly in the above order.
Item Citations and Data