An in vitro intestinal platform with a self-sustaining oxygen gradient to study the human gut/microbiome interface

Area of Science:

• Gastroenterology
• Microbiology
• Biomedical Engineering

Background:

• Colonic crypts exhibit an oxygen gradient crucial for stem cell proliferation and microbial colonization.
• Understanding this gradient is key to studying intestinal homeostasis and disease.

Purpose of the Study:

• To develop an in vitro model that replicates the physiological oxygen gradient found in colonic crypts.
• To investigate the impact of this gradient on epithelial cell behavior and microbial growth.

Main Methods:

• Primary human colonic epithelial cells were cultured in a device with tailored oxygen permeability.
• An oxygen gradient was established between luminal (0.8% O2) and basal (11.1% O2) compartments.
• Co-culture with anaerobic bacteria (Lactobacillus rhamnosus, Bifidobacterium adolescentis, Clostridium difficile) was performed.

Main Results:

• A stable oxygen gradient was maintained across viable and polarized colonic epithelial cells.
• Facultative and obligate anaerobes successfully colonized the oxygen-depleted luminal compartment.
• The oxygen gradient promoted compartmentalization of proliferative cells to the crypt base in vitro.

Conclusions:

• The developed platform effectively mimics the physiological oxygen gradient of colonic crypts.
• This system supports both epithelial cell function and anaerobic microbial co-culture.
• It offers a valuable tool for studying intestinal physiology and the gut microbiome.