TRPV1 and irritable bowel syndrome: However, in another study of colonic biopsies from healthy individuals and patients with active IBD (including UC as well as Crohn’s disease), TRPV1 expression in colonic epithelium and infiltrated inflammatory cells was found significantly upregulated in IBD patients vs. controls (Luo et al., 2017) with no significant correlation detected between the level of TRPV1 expression and disease severity.