Induction of endothelial-leukocyte interaction by interferon-gamma requires coactivation of nuclear factor-kappaB.
To determine whether nuclear factor (NF)-kappaB is necessary to confer endothelial cell responsiveness to interferon (INF)-gamma in terms of vascular cell adhesion molecule (VCAM)-1 expression and leukocyte adhesion, human endothelial cells were treated with IFN-gamma in the presence of low concentrations (LCs) of interleukin (IL)-1alpha (</=100 pg/mL), which activates NF-kappaB but does not induce VCAM-1 expression. Although IFN-gamma induced major histocompatibility complex class II antigen expression and although a high concentration of IL-1alpha (10 ng/mL) induced leukocyte adhesion and VCAM-1 expression, neither IFN-gamma nor LC IL-1alpha was able to induce VCAM-1 expression or leukocyte adhesion. However, the combination of IFN-gamma and LC IL-1alpha induced VCAM-1 expression and increased leukocyte adhesion (67% and 49% of high-concentration IL-1alpha, respectively). Electrophoretic mobility shift assays and immunoblotting of nuclear extracts showed that IFN-gamma activated signal transducers and activators of transcription (STAT)-1alpha and interferon regulatory factor (IRF)-1 but not NF-kappaB, whereas LC IL-1alpha activated NF-kappaB but not STAT-1alpha or IRF-1. Nuclear run-on studies showed that LC IL-1alpha is necessary but not sufficient for inducing VCAM-1 gene transcription and that the combination of IFN-gamma and LC IL-1alpha is required for full VCAM-1 gene transcription. These findings suggest that factors that activate NF-kappaB can synergize with IFN-gamma in promoting endothelial-leukocyte interaction.
De Caterina
R
R
Vascular Medicine Unit, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
Bourcier
T
T
Laufs
U
U
La Fata
V
V
Lazzerini
G
G
Neish
A S
AS
Libby
P
P
Liao
J K
JK
D000818:Animals; D015815:Cell Adhesion Molecules; D002450:Cell Communication / Q000187:drug effects* / Q000502:physiology; D004268:DNA-Binding Proteins / Q000502:physiology; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D050835:Interferon Regulatory Factors; D050832:Interferon-Stimulated Gene Factor 3; D007371:Interferon-gamma / Q000494:pharmacology* / Q000502:physiology; D007375:Interleukin-1; D007962:Leukocytes / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D008297:Male; D016328:NF-kappa B / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D014157:Transcription Factors / Q000502:physiology; D019010:Vascular Cell Adhesion Molecule-1 / Q000502:physiology; D000099218:Interferon Regulatory Factor-4
D015815:Cell Adhesion Molecules; D004268:DNA-Binding Proteins; D050835:Interferon Regulatory Factors; D050832:Interferon-Stimulated Gene Factor 3; D007371:Interferon-gamma; D007375:Interleukin-1; D016328:NF-kappa B; D014157:Transcription Factors; D019010:Vascular Cell Adhesion Molecule-1; D000099218:Interferon Regulatory Factor-4; C079868:gamma interferon activation factor