TLR-4 mediates the expression of adhesion molecules in vascular endothelial cells from mice induced by anti-β2GPI–IgG. C3H/HeN mice (TLR-4 intact; n=8 in each group) and C3H/HeJ mice (TLR-4 defective; n=8 in each group) were treated by intraperitoneal injection of NR-IgG (100 µg antibody per injection), anti-β2GPI–IgG (100 µg antibody per injection) at time 0 and 48 h. Aortas were collected at 72 h after the first injection. Mice in positive control group were challenged with LPS (1 µg/g body-weight) 2 h before the experiment. The expression levels of (A) ICAM-1, (B) E-selectin and (C) VCAM-1 were detected by immunohistochemistry with corresponding antibodies. The images are representative of three separate experiments with similar results. Magnification, ×40. TLR-4, Toll-like receptor-4; NR-IgG, isotype control antibody; Anti-β2GPI, anti-β2-glycoprotein I; LPS, lipopolysaccharide; ICAM-1, intercellular cell adhesion molecule-1; VCAM-1, vascular cell adhesion molecule-1.