Blood regulatory T cells in inflammatory bowel disease, a systematic review, and meta-analysis

Mobina Jalalvand; Samaneh Enayati; Maryam Akhtari; Elham Madreseh; Ahmadreza Jamshidi; Elham Farhadi; Mahdi Mahmoudi; Aliakbar Amirzargar

doi:10.1016/j.intimp.2023.109824

Blood regulatory T cells in inflammatory bowel disease, a systematic review, and meta-analysis

Int Immunopharmacol. 2023 Apr:117:109824. doi: 10.1016/j.intimp.2023.109824. Epub 2023 Feb 22.

Authors

Mobina Jalalvand¹, Samaneh Enayati¹, Maryam Akhtari², Elham Madreseh³, Ahmadreza Jamshidi¹, Elham Farhadi², Mahdi Mahmoudi⁴, Aliakbar Amirzargar⁵

Affiliations

¹ Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran.
² Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran; Inflammation Research Center, Tehran University of Medical Sciences, Tehran, Iran.
³ Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran; Inflammation Research Center, Tehran University of Medical Sciences, Tehran, Iran; Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
⁴ Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran; Inflammation Research Center, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: mahmoudim@tums.ac.ir.
⁵ Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: amirzara@tums.ac.ir.

PMID: 36827916
DOI: 10.1016/j.intimp.2023.109824

Abstract

Introduction: Inflammatory bowel disease (IBD) is an autoimmune disease involving various parts of the gastrointestinal (GI) tract, which includes Crohn's disease (CD) and ulcerative colitis (UC). Due to the contradictory results regarding the percentage of peripheral blood (PB) regulatory T cells (Tregs) in IBD patients, this meta-analysis aimed to determine the Tregs frequency in IBD patients.

Method: We searched PubMed, Web of Science, SCOPUS, and Google Scholar databases for relevant observational articles that analyzed and reported the frequency of PB Tregs in IBD patients and healthy control groups. After choosing the related articles by two reviewers, the data regarding the definition of Tregs and their frequencies in different groups were recorded.

Result: In 22 studies, the results showed a nonsignificant difference in the frequency of PB Tregs between IBD cases and control subjects (SMD: -0.27, 95 % CI: -0.78, 0.23). However, the frequency of CD4⁺CD25⁺CD127^- (SMD: -0.89, 95 % CI: -1.52, -0.26) and CD4⁺CD25⁺FoxP3⁺ (SMD: -1.32, 95 % CI: -2.37, -0.26) Tregs were significantly lower in IBD cases, compared to healthy subjects. Also, UC cases and active IBD cases showed a significantly lower frequency of Treg cells, compared to controls and remission IBD cases, respectively (SMD: -0.68, 95 % CI: -1.24, -0.11 and SMD: -0.60, 95 % CI: -0.93, -0.27).

Conclusion: Our study highlighted a probable decrease of Tregs in IBD patients, especially the patients with active states of the disease. The decrease of Treg cells might cause an imbalance in the immune system and the over-activation of auto-immune responses against the digestive tract.

Keywords: Crohn's disease; Inflammatory bowel disease; Meta-analysis; Regulatory T cells; Ulcerative colitis.

Publication types

Systematic Review
Meta-Analysis

MeSH terms

Colitis, Ulcerative*
Crohn Disease*
Humans
Inflammatory Bowel Diseases*
T-Lymphocytes, Regulatory