A Novel Microphysiological Colon Platform to Decipher Mechanisms Driving Human Intestinal Permeability

Cellular and Molecular Gastroenterology and Hepatology (2021)

Abstract

Background & Aims
The limited availability of organoid systems that mimic the molecular signatures and architecture of human intestinal epithelium has been an impediment to allowing them to be harnessed for the development of therapeutics as well as physiological insights. We developed a microphysiological Organ-on-Chip platform designed to mimic properties of human intestinal epithelium leading to insights into barrier integrity.

Methods
We combined the human biopsy-derived LGR5+ organoids and Organ-on-Chip technologies to establish a micro-engineered human Colon Intestine-Chip. We characterized the proximity of the model to human tissue and organoids maintained in suspension by RNAseq analysis, and their differentiation to IECs on the Colon Intestine-Chip under variable conditions. Furthermore, organoids from different donors were evaluated to understand variability in the system. Our system was applied to understanding epithelial barrier and characterizing mechanisms driving the cytokine-induced barrier disruption.

Results
Our data highlight the importance of the endothelium and the in vivo tissue-relevant dynamic microenvironment in the Colon Intestine-Chip in the establishment of a tight monolayer of differentiated, polarized organoid-derived intestinal epithelial cells. We confirmed the effect of interferon-gamma (IFNγ) on the colonic barrier and identified reorganization of apical junctional complexes, and induction of apoptosis in the IECs as mediating mechanisms. We demonstrate that in the human Colon Intestine-Chip exposure to interleukin 22 (IL-22) induces disruption of the barrier, unlike its described protective role in experimental colitis in mice.

Conclusion
We developed a human Colon Intestine-Chip platform and demonstrated its value in the characterization of the mechanism of action of IL-22 in the human epithelial barrier. This system can be used to elucidate, in a time- and challenge-dependent manner, the mechanism driving the development of leaky gut in humans and to identify associated biomarkers.