Sensitivity of smooth Salmonella cholerae-suis var kunzendorf to killing by porcine polymorphonuclear neutrophils and its relation to mouse virulence.
Twenty-two selected strains of Salmonella cholerae-suis var kunzendorf were evaluated for their in vitro susceptibility to the actions of porcine peripheral blood polymorphonuclear neutrophils (PMNs) and/or antibody (Ab). Strains were divided into 2 groups based on their previously reported sensitivity or resistance to antibody-complement (Ab-C) lysis. Strains resistant to Ab-C lysis resisted killing by PMNs to a greater extent than strains susceptible to Ab-C lysis. In the absence of PMNs, dilute Ab alone enhanced the growth of the Ab-C sensitive strains over that of the Ab-C resistant strains. Each of the strains was also injected intraperitoneally into a group of 5 mice. Four strains were totally avirulent for mice and the other 18 strains had a mean time to death of 5.1 +/- 1.8 d. PMNs killed bacteria in both the virulent and avirulent groups but no significant differences were observed. Antibody alone had a stimulating effect on the virulent strains but no effect on the avirulent strains. The difference between these groups was highly significant P = .005.
D000818:Animals; D000907:Antibodies, Bacterial / Q000276:immunology*; D051379:Mice; D009504:Neutrophils / Q000276:immunology*; D010587:Phagocytosis; D012481:Salmonella Infections, Animal / Q000276:immunology*; D012482:Salmonella paratyphi A / Q000276:immunology* / Q000472:pathogenicity; D013045:Species Specificity; D013552:Swine / Q000276:immunology; D013553:Swine Diseases / Q000276:immunology
D000907:Antibodies, Bacterial