Interaction of Shigella with Bifidobacteria

Abstract

We examined the effects of normal components of intestinal microflora on Shigella infection, using tissue culture infection assay. A Bifidobacterium infantis strain, both viable cells and culture supernatant, interfered strongly with the invasion and/or intracellular multiplication of Shigella organisms. Viable cells of Escherichia coli, Streptococcus faecalis, and Bifidobacterium breve also reduced, to a lesser degree, the percentage of infected HeLa or Henle 407 cells by Shigella, but those of Bacteroides fragilis had no inhibitory effect.