Translational Animal Models in Colitis: From Rodents to Pig and Minipig Platforms.

Inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), is a chronic relapsing inflammatory disorder characterized by epithelial barrier dysfunction, immune dysregulation, microbiota imbalance, and progressive tissue remodeling. Because the pathogenesis of IBD involves complex interactions among genetic, immunological, microbial, and environmental factors, experimental animal models have become indispensable tools for investigating disease mechanisms and evaluating therapeutic strategies. Various experimental colitis models have been developed to reproduce distinct pathological features of human IBD, including chemically induced models, genetically engineered systems, adoptive immune-transfer models, and infectious or microbiota-associated models. Rodent models remain the most widely used experimental platforms because of their accessibility, reproducibility, and well-established genetic manipulation technologies. These systems have significantly contributed to understanding inflammatory signaling pathways, epithelial barrier injury, immune cell dysregulation, and gut microbial crosstalk. However, important species-specific differences in intestinal anatomy, immune responses, microbiota composition, and pharmacokinetics limit direct translation of rodent findings into clinical applications. To overcome these limitations, increasing attention has been directed toward large-animal models, particularly pig and minipig systems, which more closely resemble human gastrointestinal anatomy, digestive physiology, immune regulation, and microbiome-related characteristics. Porcine models additionally support clinically relevant procedures, including repeated colonoscopy, serial biopsy sampling, pharmacokinetic evaluation, and longitudinal therapeutic monitoring. Recent advances in genome-editing technologies and multi-omics approaches have further enhanced the translational utility of porcine IBD models. This review summarizes major experimental colitis animal models, discusses their pathological and translational characteristics, and highlights the growing importance of pig and minipig systems as human-applicable platforms for preclinical therapeutic evaluation and translational IBD research.