SERPINE1 and Crohn disease: SERPINE1, encoding plasminogen activator inhibitor-1 (PAI-1), has been previously observed to be up-regulated in inflamed Crohn’s disease mucosa.40 Increased PAI-1 transcripts have been detected in active fibrotic bowel lesions, and inhibition through TM5275 has demonstrated efficacy in attenuating fibrogenesis in mouse models,41 suggesting promise as an anti-fibrotic drug.