Biomedical Engineering Reference
In-Depth Information
ICAM-2
Fig. 3
Ef ect of OPG on HUVEC gene expression detected using SuperArray membranes. Results
are representative of one of three independent experiments. Endothelial cells were incubated
with 0 treatment (i), TNF-a(50 U/mL) (ii), OPG (10 ng/mL) (iii), and OPG (10 ng/mL)/
TNF-a(50 U/mL) (iv). Dif erences in the expression of genes such as 1, angiopoietin-2; 2,
VCAM-1; 3 E-selectin are noted by an arrowhead. (B) Bars and error bars represent mean
± standard error of intensities for specii c genes from three independent membranes. OPG
signii cantly increased expression of E-selectin and ICAM-2 on activated HUVECs. *p < 0.05.
Reproduced with permission from Mangan
et al.
(2007).
In view of these published i ndings, we reasoned that the ability of OPG to
upregulate Ang-2 could underlie its TNF-α sensitizing ef ect on endothelial cells.
We used small interfering RNA (siRNA) to reduce Ang-2 expression in cultured
endothelial cells. When endothelial cell Ang-2 expression was attenuated, the
ability of OPG to upregulate adhesion molecules in TNF-α-activated HUVECs
