Disruption of epithelial barrier integrity via altered GILZ/c-Rel/RACK1 signaling in inflammatory bowel disease (IBD).

Background And Aim: Given the role of Receptor for Activated C Kinase 1 (RACK1) in both immune cell activation and in the maintenance of the intestinal epithelial barrier integrity, we investigated whether it was involved in inflammatory bowel disease (IBD).

Methods: RACK1 expression was analyzed in intestinal mucosal samples of healthy and IBD patients, in mice with chemically-induced colitis and in diseased in vitro 2D and 3D co-culture models by luciferase assay, RT-qPCR, Western blotting, immunofluorescence and immunohistochemistry. Based on our finding that glucocorticoid-induced leucine zipper (GILZ or tsc22d3) positively correlates with RACK1 expression in IBD patients, GILZ knock-out mice and cell silencing experiments were performed.

An model to study immune activation, epithelial disruption and stromal remodelling in inflammatory bowel disease and fistulising Crohn's disease.

At present, preclinical models of inflammatory bowel disease (IBD) are insufficient, limiting translation between research and new therapeutics. This is especially true for fistulising Crohn's disease (CD), as the severe lack of relevant models hinders research progression. To address this, we present human IBD mucosal models that recapitulate multiple pathological hallmarks of IBD simultaneously in one model system - immune cell infiltration, stromal remodelling and epithelial disruption.

Applying Stirred Perfusion to 3D Tissue Equivalents to Mimic the Dynamic In Vivo Microenvironment.

Complex three-dimensional (3D) tissue equivalents have been widely developed with applications with a multitude of organs and tissues. While these systems lead to significant improvements over conventional two-dimensional culture, the static conditions of the surrounding medium still present a limitation to the physiological relevance of these models. Medium perfusion and convective mixing can be introduced to these models through a variety of techniques using equipment such as pumps and rockers.

Bioengineering Novel Co-culture Models That Represent the Human Intestinal Mucosa With Improved Caco-2 Structure and Barrier Function.

The Caco-2 monolayer is the most widely used model of the human intestinal mucosa to study absorption. However, models lack communication from other cells present in the native intestine, such as signals from fibroblasts in the lamina propria. In this study, we have investigated the effects of fibroblasts upon the Caco-2 epithelium through two mechanisms: indirect signaling from fibroblasts and direct contact with fibroblasts.