A pathological study on the virulence of Salmonella choleraesuis associated with 50-kilobase plasmid in mice.
The virulence of Salmonella choleraesuis associated with 50-kilobase plasmid was assessed by the pathology produced in mice. The strains used in this study were plasmid-contained RF-1, plasmid-cured 31N-1 and plasmid-reintroduced 31N-1-T. Mice were intraperitoneally inoculated with sublethal doses of these bacteria and chronologically necropsied. Pathologically, the plasmid-positive (P+) cases were distinctly different from the plasmid-negative (P-) ones, especially in the peritoneal fluids and peritoneum. The P+ cases were characterized by extensive, granulomatous peritoneal lesions composed of abundant macrophages frequently with neutrophils, sero-fibrinous exudates and vasculitis and the bacterial antigens were detected in such sites. By contrast, the peritonea in the P- cases were mildly involved and had scattered granulomas. The bacterial antigens were hardly visible in all tissues examined. It is suggested that spread preparations of the mesentery may be a useful tool for observing the distribution of peritoneal lesions.
Moriguchi
R
R
Kitasato Institute, Tokyo, Japan.
Kawahara
K
K
Haraguchi
Y
Y
Danbara
H
H
D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology; D001202:Ascitic Fluid / Q000276:immunology; D005260:Female; D007124:Immunoenzyme Techniques; D008643:Mesentery / Q000473:pathology; D051379:Mice; D008813:Mice, Inbred ICR; D010957:Plasmids / Q000235:genetics*; D012475:Salmonella / Q000235:genetics / Q000276:immunology / Q000472:pathogenicity*; D012481:Salmonella Infections, Animal / Q000235:genetics / Q000276:immunology / Q000473:pathology*; D014774:Virulence
D000942:Antigens, Bacterial