Location of stem cells for the enteric nervous system

Area of Science:

• Developmental Biology
• Neuroscience
• Gastroenterology

Background:

• Hirschsprung disease results from incomplete colonization of the embryonic gut by neural crest-derived cells (NCC).
• Previous research indicated a small group of NCC at the leading edge of migration can innervate the entire distal gut.
• The distribution and stem cell potential of NCC throughout the developing enteric nervous system (ENS) remain largely unknown.

Purpose of the Study:

• To investigate whether NCC capable of acting as stem cells are present throughout the developing enteric nervous system (ENS).
• To determine if the stem cell capacity of NCC is unique to those at the leading edge of migration.

Main Methods:

• Mouse gut at embryonic day 11.5 was used, with terminal colon explants cultured with proximal small intestine or cecum.
• Explants were cultured on nitrocellulose filters for 120 hours to allow fusion and colonization.
• Immunohistochemistry for neuronal markers (PGP9.5, NOS) was performed to assess enteric ganglia development.

Main Results:

• NCC successfully migrated from proximal gut segments into the aganglionic terminal colon, colonizing its entire length.
• The pattern of NCC colonization and differentiation into nitric-oxide synthase (NOS)-positive neurons was consistent regardless of NCC origin (leading edge vs. proximal).
• Vagal NCC demonstrated equivalent capacity for migration and differentiation in the terminal rectum.

Conclusions:

• Neural crest-derived cells (NCC) from both the leading edge and more proximal regions of the gut possess the ability to colonize and differentiate within the aganglionic terminal colon.
• These findings suggest that the stem cell potential for enteric nervous system (ENS) development may be distributed more broadly among NCC than previously thought.
• Further research is needed to definitively identify which migrating NCC exhibit ENS stem cell properties.