Regulation of the expression of intercellular adhesion molecule 1 in cultured human endothelial cells derived from rheumatoid synovium.
OBJECTIVE
To examine the regulation of intercellular adhesion molecule 1 (ICAM-1) in human synovial microvascular endothelial cells (HSE) and human umbilical vein endothelial cells (HUVE) upon exposure to a variety of agents.


METHODS
Cultured endothelial cells were treated with various cytokines alone and in combination. The expression of ICAM-1 was evaluated at several levels, including an investigation of messenger RNA (mRNA) and surface protein expression.


RESULTS
Treatment of HSE with interleukin-1 alpha (IL-1 alpha) or tumor necrosis factor alpha (TNF alpha) resulted in minimal increases in ICAM-1 expression, in contrast to findings with HUVE. Incubation of HUVE or HSE with IL-1 or TNF in combination with interferon-gamma (IFN gamma) greatly potentiated the increase in ICAM-1 surface expression. The synergistic effect of IFN gamma and TNF was confirmed by several methods, including a cell-based enzyme-linked immunosorbent assay, fluorescence-activated cell sorting, immunofluorescence staining, and determination of mRNA levels. IFN gamma also augmented the actions of several other agonists on HSE, i.e., IL-4, lipopolysaccharide, and TNF beta/lymphotoxin. Immunoprecipitation of TNF alpha + IFN gamma-stimulated, 125I-labeled HSE cells with anti-ICAM-1 revealed a single 90-kd band, similar in size to ICAM-1 from HUVE treated in an identical manner. Unexpectedly, IFN gamma alone was a potent stimulus for HSE ICAM-1 mRNA synthesis, but was relatively ineffective in HUVE.


CONCLUSIONS
These studies indicate that IFN gamma plays a critical synergistic role in the regulation of ICAM-1 expression in human synovial endothelial cells.
Gerritsen
M E
ME
Institute for Inflammation and Autoimmunity, Miles Inc., West Haven, CT 06516.
Kelley
K A
KA
Ligon
G
G
Perry
C A
CA
Shen
C P
CP
Szczepanski
A
A
Carley
W W
WW
D000293:Adolescent; D000328:Adult; D001172:Arthritis, Rheumatoid / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D016207:Cytokines / Q000494:pharmacology*; D004727:Endothelium / Q000187:drug effects / Q000378:metabolism; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D018799:Intercellular Adhesion Molecule-1; D008875:Middle Aged; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism*; D013583:Synovial Membrane / Q000187:drug effects / Q000378:metabolism*; D013997:Time Factors; D014471:Umbilical Veins / Q000187:drug effects / Q000378:metabolism*
D015815:Cell Adhesion Molecules; D016207:Cytokines; D012333:RNA, Messenger; D018799:Intercellular Adhesion Molecule-1