EXPERIMENTAL SALMONELLOSIS

Abstract

Infection in vitro with Salmonella enteritidis of mononuclear phagocytes derived from the abdominal cavity of mice showed that the intracellular multiplication of virulent strain 116-54 was rapid, and phagocytes were destroyed within 3 days of incubation. However, the intracellular growth of attenuated strain was inhibited after a slight increase in number of bacteria, and reached a "carrier state." Serum obtained from normal mice or from mice immunized with live or dead vaccine had no inhibitory effect on intracellular growth of virulent strain 116-54. Cells obtained from mice immunized with live vaccine inhibited intracellular multiplication of virulent strain 116-54, regardless of the presence of antibody in the medium, whereas the cells of mice immunized with dead vaccine did not.