Importance of CCL25 in the attraction of T cells and the role of IL-7 on the signaling pathways in intestinal epithelial cells

• Published in: Immunobiology (1979) Vol. 214; no. 6; pp. 403 - 409
• Main Authors: Calabrese, Graciela C, Luczak, Erica N, Estela Roux, M
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier GmbH 2008
• Subjects: Advanced Basic Science; Allergy and Immunology; Animals; Apoptosis; Bcl-2; CCL25; Chemokines, CC - genetics; Chemokines, CC - metabolism; Chemotaxis, Leukocyte; IL-7; Immunologic Deficiency Syndromes - immunology; Immunologic Deficiency Syndromes - metabolism; Immunologic Deficiency Syndromes - pathology; Interleukin-7 - genetics; Interleukin-7 - metabolism; Intestinal epithelial cells; Intestinal Mucosa - cytology; Intestinal Mucosa - immunology; Intestinal Mucosa - metabolism; Male; Malnutrition - immunology; Malnutrition - metabolism; Malnutrition - pathology; NF-kappa B - metabolism; NF-κB; Proto-Oncogene Proteins c-bcl-2 - metabolism; Rats; Rats, Wistar; Receptors, Antigen, T-Cell, gamma-delta - metabolism; RNA, Messenger - genetics; RNA, Messenger - metabolism; Secondary immunodeficiency; Signal Transduction - immunology; Stat3; STAT3 Transcription Factor - metabolism; T-Lymphocyte Subsets - immunology; T-Lymphocyte Subsets - metabolism; Bcl-2; CCL25; intestinal epithelial cells; LP; thymus-expressed chemokine; Secondary immunodeficiency; R 21; experimental group; intestinal intra-epithelial lymphocytes; C 60; control group; IECs; IL-7; NF-κB; TECK and CCL25; RT-PCR; iIEL; lamina propria; reverse transcriptase polymerase chain reaction; Stat3; Intestinal epithelial cells
• ISSN: 0171-2985; 1878-3279
• DOI: 10.1016/j.imbio.2008.12.008

Abstract We have demonstrated an inflammatory process triggered by a dietary antigen accompanied with an increase of TNF-α in an experimental model of secondary immunodeficiency. TNF-α regulates the increase of γδ T subpopulation both in lamina propria and in the intestinal intraepithelium, where IL-7 influences γδ T cells development. TECK (CCL25) is important in the attraction and generation of T and B lymphocytes to the small intestine, lamina propria and intraepithelium. In the present study we evaluate CCL25 and IL-7 mRNA levels, by semiquantitative RT-PCR in intestinal epithelial cells. Lower levels of CCL25 mRNA were detected in animals after re-feeding compared to the well-nourished ones ( P <0.05), whereas an increase of 1.5 fold of IL-7 mRNA was registered in the experimental group ( P <0.05). When studying the intestinal epithelial cell distribution of the transcriptional factors NF-κB and Stat3, they were predominantly accumulated in the nucleus of cells isolated from the malnourished group, whereas they remain in the cytosol of the control one. The finding of an apoptosis decrease in intestinal epithelial cells isolated from malnourished animals was in agreement with the increased amount of Bcl-2 found in the mitochondrial fraction of this experimental group. All the above findings may lead us to conclude that we are in the presence of a mechanism by which γδ+T cells are increased in the intestinal villi, through different signaling pathways mediated by CCl25 and IL-7.