EP533 - Modeling Inflammatory Bowel Disease Using Human-Derived Intestinal Monolayers for Drug Discovery

Purpose/Background: Inflammatory bowel disease affects millions worldwide and is characterized by chronic intestinal inflammation, epithelial barrier dysfunction, and disrupted mucosal homeostasis. Relapsing symptoms, hospitalizations, and diminished quality of life, coupled with limited treatments and high nonresponse rates, emphasize the urgent need for novel therapies and scalable, human-relevant preclinical models. To address this challenge, we established a primary human intestinal monolayer platform derived from healthy human ileum and colon tissues and developed functional assays to quantify inflammation-induced changes in barrier integrity and mucus production. We hypothesize that these primary monolayers reproduce hallmark disease-associated changes in epithelial physiology, providing a robust platform for preclinical drug screening.

Methods/Interventions: Primary intestinal epithelial cells were isolated from ileum and colon tissues of human organ donors and cultured as polarized monolayers on transwell inserts. To model inflammation, monolayers were treated with the proinflammatory cytokines IFNγ, IL-1β, and TNFα. Barrier integrity was assessed using transepithelial electrical resistance (TEER) and fluorescent dextran permeability assays.

Results/Outcomes: Inflamed monolayers exhibited markedly reduced barrier function, with TEER values approximately 50% lower than controls (p < 0.001) and ~2.5-fold higher dextran permeability (p < 0.001). Monolayer mucus production was quantified biochemically using Alcian blue staining and was found to be elevated by ~35% in inflamed monolayers (p < 0.02). Inflamed monolayers consistently exhibited reduced TEER, increased dextran permeability, and elevated mucus secretion, capturing key features of IBD such as epithelial barrier compromise and, in some cases, excessive mucus production.

Conclusion/Discussion: These results demonstrate that primary human intestinal monolayers provide a quantifiable, physiologically relevant model of inflammation-induced epithelial dysfunction. Importantly, patient-derived monolayers could retain the genetic, epigenetic, and disease-specific characteristics of the donor tissue, offering a platform that can faithfully model individual IBD phenotypes. This scalable, human-derived system enables the evaluation of candidate therapeutics aimed at restoring barrier integrity and modulating mucus production, supporting the development of more effective IBD treatments.

Primary human intestinal monolayers derived from healthy donor tissues.
(a) Human ileum-derived and (b) human colon-derived epithelial monolayers cultured on transwell inserts under noninflammatory conditions. Both form confluent, polarized epithelial layers with intact morphology, demonstrating the successful establishment of primary human intestinal monolayers from donor tissue.
Cytokine-induced inflammation disrupts epithelial barrier integrity in primary human colon monolayers.
(a) Transepithelial electrical resistance (TEER) measurements showing a notable reduction in TEER in cytokine-treated (IFNγ, IL-1β, TNFα) inflamed monolayers compared to untreated controls (p < 0.001). (b) Fluorescent dextran permeability assays using lucifer yellow, 10 kDa, and 70 kDa dextrans demonstrate significantly increased permeability for lucifer yellow and 10 kDa dextrans in inflamed monolayers, with minimal change for 70 kDa dextran, indicating cytokine-induced compromise of epithelial barrier integrity in human colon monolayers.