Beneficial Bacteria

When newborn babies first experience the world, bacteria swoop in to make a home in their guts. This is vital for a healthy digestive system. However in premature babies this process can be harmful. To understand why, researchers first investigated how normal newborn guts react. They modelled the immature gut epithelium of newborns using human stem cells that were encouraged in the lab, using chemicals, to become intestinal organoids (pictured). Next they added Escherichia coli bacteria and found they helped the gut epithelium develop by reducing oxygen levels (second panel) as when oxygen was limited artificially without E. coli (fourth panel). This was detected using a marker for low oxygen, PMDZ (red), absent in epithelium that had no (first panel) or defective (third panel) E. coli. Reduced oxygen spurred on antimicrobial production, mucus layer development and barrier formation – all measures that would help protect a newborn gut.

Written by Lux Fatimathas

• Image from work by David R Hill and colleagues
• Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
• Image originally published under a Creative Commons Licence (BY 4.0)
• Published in eLife, November 2017