Expression of Toll-like receptor 2 (TLR2), TLR4, and CD14 in biopsy samples of patients with inflammatory bowel diseases: upregulated expression of TLR2 in terminal ileum of patients with ulcerative colitis.
Dysregulation of innate and adaptive intestinal immune responses to bacterial microbiota is supposed to be involved in pathogenetic mechanisms of inflammatory bowel diseases (IBDs). We investigated expression of Toll-like receptor 2 (TLR2), TLR4, and their transmembrane coreceptor CD14 in biopsy samples from patients with IBD and in non-inflamed gut mucosa from controls. Small intestine and colon samples were obtained by colonoscopy from patients with Crohn's disease (CD), ulcerative colitis (UC), and controls. Immunohistochemical analysis of cryostat sections using polyclonal and monoclonal antibodies specific for TLR2, TLR4, and CD14 showed a significant increase in TLR2 expression in the terminal ileum of patients with inactive and active UC against controls. Significant upregulation of TLR4 expression relative to controls was found in the terminal ileum and rectum of UC patients in remission and in the terminal ileum of CD patients with active disease. CD14 expression was upregulated in the terminal ileum of CD patients in remission and with active disease, in the cecum of UC patients in remission and with active disease, and in rectum of UC patients with active disease. Hence, dysregulation of TLR2, TLR4, and CD14 expression in different parts of the intestinal mucosa may be crucial in IBD pathogenesis.
Frolova
Lenka
L
Department of Immunology and Gnotobiology, Institute of Microbiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic.
Drastich
Pavel
P
Rossmann
Pavel
P
Klimesova
Klara
K
Tlaskalova-Hogenova
Helena
H
D001706:Biopsy; D002432:Cecum / Q000378:metabolism / Q000473:pathology; D003093:Colitis, Ulcerative / Q000378:metabolism* / Q000473:pathology; D003424:Crohn Disease / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007082:Ileum / Q000378:metabolism / Q000473:pathology; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000378:metabolism / Q000473:pathology; D018950:Lipopolysaccharide Receptors / Q000096:biosynthesis*; D012007:Rectum / Q000378:metabolism / Q000473:pathology; D051195:Toll-Like Receptor 2 / Q000096:biosynthesis*; D051197:Toll-Like Receptor 4 / Q000096:biosynthesis*
D018950:Lipopolysaccharide Receptors; C495342:TLR2 protein, human; C495345:TLR4 protein, human; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4