Intestinal models play a pivotal role in drug research and development. Their application includes drug adsorption studies, studying loss of barrier function due to drug induced toxicity as well as modelling a range of diseases including inflammatory bowel disease (IBD), Coeliac disease, Bile acid malabsorption, Ischemic colitis, Radiation colitis and infection colitis. The OrganoPlate® can be used to grow perfused intestinal tubules and interrogate membrane function. Intestinal tubules can be grown at almost any complexity, from monocultures to complex co-cultures with immune cells, bloodvessel and stromal tissue.
- Formation of 40 leak-tight intestinal tubes in the OrganoPlate®
- No interference by artificial membranes
- Real-time and high throughput barrier function measurement by microscopy or TEER
- Modelling inflammatory effects by addition of cytokines or immune cells
- Glomerular cells generate layer of extracellular matrix composed by collagen IV and laminin
- Complex co-culture increase the relevance of the model
The OrganoPlate® 3-lane comprises 40 microfluidic chips that can be used to culture miniaturized tissues and organs (Figure 1a-b). The gut tubule is grown against an extracellular matrix gel (middle channel). Figure 1e shows a tubule from Caco-2 cells, mimicking the colon. The tubules have a clear lumen representing the apical side and interface with the collagen gel with the basal side. Apical localization of Ezrin indicates correct polarization of these tubes. The third channel is used for basal access to the tube.
Barrier function & disease
Barrier function of the gut model can be assessed using trans epithelial electrical resistance (TEER) measured in the OrganoTEER . The OrganoTEER is capable of measuring all 40 tubes of the OrganoPlate 3-lane in parallel, and under flow conditions under a minute. Figure 2a shows increasing TEER values over the first 4 days of culture, followed by stabilization. Barrier integrity can also be assessed by microscopy. In this assay, a fluorescent dye is perfused through the lumen of the model’s endothelial vessel. Figure 2b shows disruption of the barrier by staurosporine exposure and figure 2c shows a dynamic EC50 curve demonstrating the impact of both dose as well as exposure time. In figure 2d barrier function is compromised through a cocktail of cytokines mimicking inflammatory bowel disease. The phenotype could be prevented by knockdown of an IBD specific gene or compound. Other assays that could be run on this model include transported assays, as described for the kidney and neuro-vascular unit.
Caco-2 cells have a phenotype resembling enterocytes of the small intestine. By adding goblet-likecells, it is possible to increase the mucus secretion in the lumen of the tubule (see figure 3). The in-vivo situation can be even further mimiced by increasing complexity through adding intestinal myofibroblasts in the gel and a blood vessel, as well as immune cells to the lumen of the blood vessel. The platform could also be used to grow intestinal organoids into a tube or primary intestinal material.
This work was supported by the European Union under grant agreements #674983 (ITN-MIMIC) and #641639 (ITN-BIOPOL)