MAdCAM-1 expression and regulation in murine colonic endothelial cells in vitro.
BACKGROUND
Although the mucosal addressin cell adhesion molecule-1 (MAdCAM-1) is associated with the etiology of inflammatory bowel diseases, few studies have directly examined MAdCAM-1 using microvascular endothelium derived from the colon. This study measured the expression of MAdCAM-1 in a novel colon endothelial line MJC-1, as well as MAdCAM-1 regulation and function in vitro.


METHODS
We cloned microvascular endothelial cells from primary colon cultures using ImmortoMice mice (whose cells express a temperature-sensitive SV40 large T antigen, H-2Kb-tsA58 mice). Expression of MAdCAM-1 after stimulation with cytokines [tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, or interferon (IFN)-gamma] was determined by Western blotting. Signal paths regulating MAdCAM-1 expression were examined using pharmacological blockers before cytokines. We also examined lymphocyte adhesion using lymphocytes that constitutively express alpha4beta7 integrin.


RESULTS
TNF-alpha induced MAdCAM-1 in a dose-dependent manner by 24 hours. MAdCAM-1 induction was protein kinase C, tyrosine kinase, p38 mitogen activated protein kinase, and nuclear-factor kappa-B/poly adenosine diphosphate ribose polymerase dependent. Lymphocyte adhesion was increased 2.6-fold after TNF-alpha stimulation and was inhibited by anti-MAdCAM-1 antibody before treatment (P < 0.05 control versus TNF-alpha).


CONCLUSIONS
In vitro, MAdCAM-1 can be induced on colon endothelial cells by TNF-alpha stimulation and may represent a useful model to study microvascular injury in the large intestine.
Ando
T
T
LSU Health Sciences Center, Shreveport, Louisiana 71130-3932, USA.
Jordan
P
P
Wang
Y
Y
Itoh
M
M
Joh
T
T
Sasaki
M
M
Elrod
J W
JW
Carpenter
A
A
Jennings
M H
MH
Minagar
A
A
Alexander
J S
JS
D000818:Animals; D000952:Antigens, Polyomavirus Transforming / Q000235:genetics; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules; D018929:Cell Culture Techniques; D003106:Colon / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000502:physiology; D020869:Gene Expression Profiling; D007136:Immunoglobulins / Q000096:biosynthesis* / Q000494:pharmacology*; D007413:Intestinal Mucosa / Q000502:physiology; D008214:Lymphocytes / Q000502:physiology*; D051379:Mice; D008822:Mice, Transgenic; D009088:Mucoproteins / Q000096:biosynthesis* / Q000494:pharmacology*; D011493:Protein Kinase C / Q000494:pharmacology; D016201:Receptors, Lymphocyte Homing; D015290:Second Messenger Systems / Q000502:physiology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
D000952:Antigens, Polyomavirus Transforming; D015815:Cell Adhesion Molecules; D007136:Immunoglobulins; C489082:Madcam1 protein, mouse; D009088:Mucoproteins; D016201:Receptors, Lymphocyte Homing; D014409:Tumor Necrosis Factor-alpha; D011493:Protein Kinase C