Functional and morphological characterisation of human colonoid-derived monolayers under inflammatory conditions

Abstract

Despite progress in the diagnosis and treatment of inflammatory bowel disease (IBD), its incidence and prevalence continue to rise. The lack of human preclinical models limits the ability to study disease mechanisms and develop effective therapies. Human colonoids provide a physiologically relevant in vitro system that closely mimics the colonic epithelium. In this study, we established an in vitro IBD model using colonoid-derived monolayers and induced inflammation through exposure to TNF-α and IFN-γ. This treatment significantly impaired epithelial barrier integrity and increased the secretion of inflammatory mediators, like IL-8 and CCL20. Although cell metabolic activity was largely preserved, a cytotoxic effect was observed: the increased apoptosis, revealed also by confocal microscopy, and a compromised epithelial renewal, suggested by lower LGR5 mRNA transcription, were evidenced. Functionally, inflammatory conditions led to a significant increase in the paracellular transport of atenolol, while the transport of propranolol remained unaffected, highlighting the impact of intestinal inflammation on oral drug absorption and bioavailability. This model provides a robust platform for studying IBD-related epithelial dysfunctions and evaluating potential therapeutic interventions.