Toll-like receptor 7 a novel non-invasive inflammatory genetic sensor for ulcerative colitis remission monitoring


1 Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran

2 Mahak Hematology Oncology Research Center (Mahak-HORC), Mahak Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran

3 Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran

4 Department of Regenerative Medicine, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran


Background: Ulcerative colitis (UC) and Crohn's disease (CD) are two major types of inflammatory bowel diseases (IBDs). Toll-like receptors (TLRs) are expressed in the innate immune system compartments, in charge of identifying a wide range of microorganisms. The aim of the present study was to evaluate the expression of TLR-2, -7, and -8 in peripheral blood mononuclear cells (PBMC) of UC patients as a novel non-invasive primary inflammation sensor for monitoring the clinical course of UC candidates.
Materials and Methods: In this cross-sectional study, total RNA was extracted from the PBMC of 42 UC patients along with 20 healthy donors. The mRNA levels of TLR-2, -7, and -8 were assessed using the quantitative real-time polymerase chain (qRT-PCR) reaction.
Results: The present research study demonstrated no significant changes in TLR-2 mRNA expression in UC patients in comparison with the control group (P = 0.1264), whereas significant elevation (P = 0.0008) was distinguished in the TLR-7 expression of UC participants specifically during the remission course compared with healthy donors and flareup patients (P = 0.0004 and P = 0.0063, respectively). The last selected TLR, TLR-8 was not shown remarkable changes either between UC patients and the control group or between clinical courses of the disease.
Conclusion: Here, among three nominated TLRs for predicting UC patients, TLR-7 was potentially selected according to the significant difference in mRNA expression in flareup UC patients and control donors. TLR-7 could be used as a novel non-invasive biomarker for monitoring UC patients in the active course of the disease.


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