Published online Mar 7, 2023. doi: 10.3748/wjg.v29.i9.1475
Peer-review started: December 5, 2022
First decision: January 2, 2023
Revised: January 11, 2023
Accepted: February 22, 2023
Article in press: February 22, 2023
Published online: March 7, 2023
Processing time: 92 Days and 6.6 Hours
Persistent low level of inflammation due to immune dysfunction is regarded as one of the prime pathogenic mechanisms of post-infectious irritable bowel syndrome (PI-IBS). γδ T cells play a key role in innate and adaptive immunity. Adenosine and its receptors expressed on γδ T cells are involved in intestinal inflammation and immune regulation.
To unveil the role of γδ T cells regulated by adenosine 2A receptor (A2AR) in the pathogenesis of PI-IBS.
This study aims to investigate the role of A2AR in γδ T cells and γδ T cells in PI-IBS.
A PI-IBS mouse model was established with Trichinella spiralis (T. spiralis) infection. Intestinal A2AR and A2AR in γδ T cells were detected through immunohistochemistry, and inflammatory cytokines were detected through western blot. The role of A2AR on isolated γδ T cells, including γδ T cell proliferation, apoptosis and γδ T cell-mediated cytokine secretion, was assessed in vitro. A2AR expression in γδ T cells was determined by western blot and reverse transcription polymerase chain reaction (RT-PCR). Mice were injected with A2AR agonist or A2AR antagonist and cultured γδ T cells were also reinfused into the animals, and then the above parameters and clinical features were examined again. In addition, alterations in A2AR-related signaling pathway molecules were detected by western blot and RT-PCR.
The expression levels of ATP and A2AR were increased in PI-IBS mice (P < 0.01), and inhibition of A2AR further enhanced the clinical features of PI-IBS, as reflected by the abdominal withdrawal reflex and colonic transport test results. The development of PI-IBS was associated with an increase in intestinal γδ T cells and cytokines including interleukin-1 (IL-1), IL-6, IL-17A and interferon-α (IFN-α). In addition, γδ T cells obtained by purification in vitro could express A2AR and promote IL-1, IL-6, IL-17A and IFN-α secretion, which is also regulated by A2AR agonists and antagonists. We also found that A2AR antagonists improved γδ T cell function through the PKA/CREB/NF-κB signaling pathway.
Our results suggested that A2AR contributes to the development of PI-IBS after T. spiralis infection via the PKA/CREB/NF-κB signaling pathway by γδ T cells.
Hypo-inflammation caused by immune dysfunction is considered to be one of the main pathogenic mechanisms of PI-IBS. In this study, we discovered that A2AR on the surface of γδ T cells can regulate the function of γδ T cell, thereby increasing inflammatory factor secretion and promoting PI-IBS progression. Luckily, the utilization of A2AR antagonists can improve PI-IBS symptoms by promoting γδ T cells’ function. Through our study, we identified A2AR, a key protein that promotes PI-IBS disease progression, and demonstrated the feasibility of antagonizing A2AR to intervene in PI-IBS, thus providing a novel therapeutic target and an effective intervention strategy for PI-IBS treatment.