Inflammation-independent TL1A-mediated intestinal fibrosis is dependent on the gut microbiome.

Tumor necrosis factor-like cytokine 1A (TL1A, TNFSF15) is implicated in inflammatory bowel disease (IBD), modulating the location and severity of intestinal inflammation and fibrosis. TL1A expression is increased in inflamed gut mucosa and associated with fibrostenosing Crohn's disease. Tl1a-overexpression in mice lead to spontaneous ileitis, and exacerbated induced proximal colitis and fibrosis.