TL1A as a Target in Inflammatory Bowel Disease: Exploring Mechanisms and Therapeutic Potential.

Inflammatory bowel diseases (IBD) are chronic disorders characterized by persistent inflammation of the gastrointestinal tract. Despite advances in treatment, a significant proportion of patients remain refractory to current therapies and develop complications, particularly fibrosis, leading to strictures and fistulae. Tumor necrosis factor-like ligand 1A (TL1A) has emerged as a promising new target for IBD treatment, due to its dual role in inflammatory and fibrotic pathways. TL1A, acting through its receptor death receptor 3 (DR3), orchestrates mucosal inflammation by enhancing T-cell activation and promoting pro-inflammatory mediator secretion. TL1A also drives intestinal fibrosis by activating fibroblasts and increasing collagen deposition. Clinical trials evaluating anti-TL1A monoclonal antibodies have shown encouraging efficacy and safety, with significant improvements in clinical remission rates, endoscopic healing, and histologic outcomes. Beyond IBD, TL1A overexpression has been implicated in other immune-mediated inflammatory diseases, highlighting its broader therapeutic potential. This review explores TL1A's role in IBD pathogenesis, the latest clinical trial data, and its involvement in extraintestinal inflammatory disorders, underscoring its potential as a novel precision-medicine target across multiple diseases.