Among differentially expressed genes, IL1B, IL17F, IL6R, CXCL2, CCL20 and CCL25
were selected based on their immunological functions and CD8B and CD81 may contribute to variations of blood T lymphocyte subsets.
Though, it is still not fully clear why there is a tropism for the gastro-intestinal tract, advancements have been made in this area, identifying the chemokine receptor 9 (CCR9) as a predisposing factor, due to its motility enhancing effects of the cells, in conjunction with the presence of its ligand, CCL25
, expressed predominantly in the thymus and the epithelium of the small intestine .
Women had about 20% less CCL25
and CCL26 than men, and 32% less CxCL1 (fracktalkine).
Based on the functional categorization of chemokines as described by Zlotnik and Yoshie , the elevated chemokines in TS-CONTROL compared to TS-COPD can be classified as follows: Inflammatory (CCL1, 7, and 15; CXCL2 and 9), homeostatic (CCL19, CCL25
), and dual function (CCL17).
[alpha]4[beta]7 and CCR9 can interact with mucosal vascular addressin cell adhesion molecule 1 (MAdCAM-1) and CC chemokine ligand 25 (CCL25
), respectively [41, 45].
(29) The [alpha]4[beta]7 specifically binds MAdCAM-1, and CCR9 is the receptor for the chemokine CCL25
secreted by small intestinal venules.
Receptors and their ligands necessary for T-cell homing in the intestine include MAdCAM-1, integrin a4b7, lymphocyte function-associated antigen-1, intercellular adhesion molecule-1, very late antigen-4 (a4b1), vascular cell adhesion protein 1, CCR9, CCL25
, P-selectin glycoprotein ligand-1, and P-selectin .
Cutaneous melanoma has a distinct pattern of metastasis, preferentially targeting the submucosa of the small intestine probably via the CCR9 lymphocytes, CCL25
thymus-expressed chemokine axis, and specific integrins .
More recently, they found that CXCL9, CXCL16, CCL20, and CCL25
were specifically involved in MSC transendothelial migration across murine aortic endothelial cells (MAECs) .
The most differentially expressed genes were related to signal transduction, such as c-jug NF-[kappa] Bp65, neurotrophic factors (e.g., Mdk), chemokine and chemokine receptors (e.g., TECKI CCL25
), and interleukins such as IL-10 and IL-5, indicating a possible involvement of DU in cancer development, autoimmune diseases, and T helper 2 polarization ofT cells.