Mechanisms of MAdCAM-1 gene expression in human intestinal microvascular endothelial cells. Am J Physiol Cell Physiol 2005 Feb;288(2):C272-81
Date
10/16/2004Pubmed ID
15483224DOI
10.1152/ajpcell.00406.2003Scopus ID
2-s2.0-12144271043 (requires institutional sign-in at Scopus site) 54 CitationsAbstract
Mucosal addressin cell adhesion molecule-1 (MAdCAM-1) is a homing receptor preferentially expressed on gut-associated endothelial cells that plays a central role in leukocyte traffic into the mucosal immune compartment. Although the molecular mechanisms underlying endothelial ICAM-1 or E-selectin expression have been intensively investigated, the mechanisms that regulate human MAdCAM-1 expression have not been defined. We report MAdCAM-1 gene and protein expression in primary cultures of human intestinal microvascular endothelial cells (HIMEC) that was not demonstrated in human umbilical vein endothelial cells. Similar to ICAM-1 and E-selectin expression, MAdCAM-1 gene expression in HIMEC was inducible with TNF-alpha, IL-1beta, or LPS activation. However, in striking contrast to ICAM-1 and E-selectin expression, MAdCAM-1 mRNA and protein expression in HIMEC was heavily dependent on culture duration and/or cellular density, suggesting a prominent role for cell-cell interaction among these endothelial cells in the expression of the mucosal addressin. MAdCAM-1 expression was inhibited by both SN-50 (NF-kappaB inhibitor) and LY-294002 [phosphatidylinositol 3-kinase (PI3-K) inhibitor], whereas ICAM-1 and E-selectin expression was inhibited by SN-50 but not by LY-294002. The Akt phosphorylation by TNF-alpha or LPS was greater at higher cell density, demonstrating a pattern similar to that of MAdCAM-1 expression. NF-kappaB activation was not affected by cellular density in HIMEC. MAdCAM-1 expression in human gut endothelial cells is regulated by distinct signaling mechanisms involving both NF-kappaB and PI3-K/Akt. These data also suggest that PI3-K/Akt is involved in the gut-specific differentiation of HIMEC, which results in expression of the mucosal addressin MAdCAM-1.
Author List
Ogawa H, Binion DG, Heidemann J, Theriot M, Fisher PJ, Johnson NA, Otterson MF, Rafiee PAuthor
Mary F. Otterson MS, MD Emeritus Professor in the Surgery department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Antigens, SurfaceBlotting, Western
Cell Adhesion Molecules
Cells, Cultured
E-Selectin
Electrophoretic Mobility Shift Assay
Endothelial Cells
Fluorescent Antibody Technique
Gene Expression
Humans
Immunoglobulins
Intercellular Adhesion Molecule-1
Intestinal Mucosa
Membrane Proteins
Mucoproteins
NF-kappa B
Phosphatidylinositol 3-Kinases
RNA, Messenger
Reverse Transcriptase Polymerase Chain Reaction
Signal Transduction









