A scalable human gut-immune co-culture model for evaluating inflammatory bowel disease anti-inflammatory therapies

Current treatments for inflammatory bowel disease (IBD) are often ineffective long-term, as many patients ultimately become unresponsive to anti-inflammatory drugs. The need for improved therapeutics is urgent. Animal models utilized for drug development are limited by interspecies variability and poor translatability. However, most in vitro models lack the sophistication to model the key interplay of the immune system with the intestinal epithelium in line with the known role of the immune system in the etiology of the disease. To address this gap, we developed a primary intestinal epithelial cell co-culture system to incorporate elements of innate immune signaling. This system models immune-epithelial interactions using RepliGut^Ⓡ - Planar Transverse Colon cultured on a Transwell™ system with THP-1 derived macrophages in a receiver compartment of a 96-well plate format, compatible with high-throughput screening (HTS) workflows. Epithelial barrier integrity and cell viability were maintained in co-culture with unstimulated macrophages. However, similar to the pathology associated with IBD, epithelial integrity was compromised in co-culture with LPS + IFN-γ pre-stimulated macrophages as evidenced by declining TEER and cell viability and increased inflammatory cytokine release. Cotreatment with anti-inflammatory IBD therapeutics adalimumab or tofacitinib mitigated these effects, demonstrating the model's ability to replicate key inflammatory responses and prevention. Reproducibility and scalability of the model system further position the model for screening and/or mechanistic interrogation of anti-inflammatory drugs, improving drug discovery, and accelerating the translation of new IBD therapies into clinical practice.