JEM: Scientists have revealed for the first time the molecular mechanism by which intestinal corted cells regulate T-cell differentiation

February 9, 2021 // -- The intestinal immune cells contain a large number of immune cells, because they will continue to be exposed to a variety of antigens, such as bacteria and food, so the appropriate induction of intestinal immune cells in the intestinal stability of China plays a key role.
recently, in a study published in the international journal Journal of Engineering Medicine, scientists from possum University of Science and Technology and others revealed for the first time the molecular mechanisms that regulate T-cell differentiation (IEL, endothystic lymphocytes) through small intestine endosthal cells (IEC).
Endoder lymphocytes are located in the endocystral tissue, which is located outside the body of a layer of endothial cells, in other words, endoder lymphocytes are located in the outer body of the immune cells, when they encounter bacteria such as symbic microorganisms can regulate the host body's immune response, therefore, the proper differentiation of endostrophal lymphocytes is essential to regulate the intestinal immune stability, however, researchers are currently very little knowledge of the small upper cortical cell layer of the upper cortical lymphocytes.
photo source: CC0 Public Domain To uncover the mystery, in this study, researchers looked for specific environmental factors at the far end of the small intestine, because endotental lymphocytes are rich in the far end of the organ, and through further study and analysis, the researchers found that the small intestine endotent Cells are able to express the primary tissue fusion complex II (MHC II) and death ligand 1 (PD-L1) induced by small intestine far-end microorganisms, and at the small intestine far-end point, CD4-T cells can be converted into endostrophy lymphocytes.
Through these molecules, small intestine endotrine cells can induce small intestinal endotrine cells to mature into endotrine lymphocytes by providing antigen-specific T-cellular stimulation (TCR) stimulation and programmed cell death protein 1 (PD-1) signals.
PD-1 signal can induce CD4-plus T cells to differentiate into endostroin lymphocytes by inhibiting the expression of ThPOK, the main transcription regulator of CD4-plus T cells, and researchers have not previously reported on ThPOK's new role in PD-1 signals.
researchers point out that T-cell differentiation, or co-stimulation induced by TCR stimulation and co-stimulation from specialized antigen delivery cells (APCs), is also induced by tissue cells, and that even within small intestine tissue, molecular expression of small intestine endocellulum cells can show regional differences between the near and far ends due to environmental factors such as symbicular microorganisms, suggesting that this process plays an important role in the regulation of immune cells in each region of the small intestine.
Finally, researcher Seung-Woo Lee explains that small intestinal endocysts can inhibit the entry of intestinal bacteria by creating CD4-plus endocial lymphocytes and placing them in the endoskin cell layer, similar to training special personnel and deploying them on the battlefield.
Actually, the occurrence of T-cell differentiation through small intestine endocial cells is not only applicable to the intestines, but also to most of the body's tissues, which may in the future help researchers delve into the role of tissue cells in them.
original source: Sookin Moon, Yunji Park, Sumin Hyeon, et al. Niche-specific MHC II and PD-L1 regulate CD4+CD8αα+ intraepithelial lymphocyte differentiation, Journal of Experimental Medicine (2021). DOI:10.1084/jem.20201665