Assessment of equine intestinal epithelial junctional complexes and barrier permeability using a monolayer culture system.

The research article presents a study on the development of a novel intestinal epithelial monolayer cell culture for equine jejunum to help find new treatments for gastrointestinal disease in horses.

Study Objectives

• The research aimed to develop and characterize a small intestinal monolayer cell culture derived from the equine jejunum.
• It intended to establish normal measurements of intestinal permeability and restitution.

Methodology

• The researchers used three-dimensional enteroids derived from postmortem sampling of the equine jejunum to develop confluent epithelial monolayers.
• Various methods like histology, RT-PCR, RNAscope, protein immunofluorescence and transmission electron microscopy were used to confirm the presence of differentiated intestinal epithelial cell types and tight junctions.
• Measurements of paracellular and transcellular permeability was done by assessing transepithelial resistance (TER) and macromolecule flux.
• Scratch assays were used to assess intestinal restitution and model it.

Findings

• The monolayer cell cultures reached 100% confluency by approximately 5-7 days.
• The equine jejunum monolayers were confirmed as epithelial in origin, with identification of differentiated intestinal epithelial cell types and evidence of tight junction proteins.
• The study reported normal TER values (179.9 ± 33.7 ohms*cm) and limited macromolecule flux (22 ± 8.8% at 60 min), indicating the proper functioning of the intestinal barrier.
• The monolayers were able to close gap defects within 24 hours following a scratch wound, suggesting their potential use in testing therapies for gastrointestinal diseases like equine colic.

Conclusion

• The research successfully established a novel intestinal epithelial monolayer cell culture model for the equine jejunum.
• This model provides valuable insights into intestinal epithelial cell differentiation, the formation of physiologically relevant barrier function and the ability of these cells to self-heal following wound.
• This model could be an effective tool in testing potential therapeutics for equine colic.