Lactobacillus Isolates That Stop the Growth of Shigella in Culture and Increase the Resistance of Cultured Epithelial Cells to Disruption by Shigella

Abstract

Diarrheal disease is one of the leading causes of death among young children in low income regions of the world, and may be due to multiple factors, one such factor being microbial infection. Among the leading causes of microbial diarrhea is Shigella; at the moment there is no vaccine or probiotic treatment to counter the threat posed by Shigella. Our ultimate goal is to generate an effective and accessible probiotic treatment. Our group recently identified that the presence of certain Lactobacillus strains in the intestinal tract protect the human host from the effects of Shigella (p<0.02). Thus, we hypothesized that some strains of Lactobacillus from children with diarrhea in Kenya would either inhibit the growth of Shigella in culture, or increase the resistance of cultured intestinal epithelial cells to attack by Shigella. We collected six strains of Lactobacillus from children in Lwak, Kenya with diarrhea. Four produce soluble compounds that stopped the growth of Shigella in culture (p=10-136). One strain also produced a soluble compound(s) that increased the resistance of a cultured intestinal epithelial monolayer (T-84 cells) to disruption by Shigella (p=0.04). Once identified, these soluble compounds may be useful for treating or preventing Shigella infections and the Lactobacillus strains may be probiotic treatments for diarrhea caused by Shigella.