Fig 1. 7-Ketocholesterol enhances monocyte adhesion to human umbilical vascular endothelial cells (HUVECs).

HUVECs were pretreated with 50 μM 7-ketocholesterol or cholesterol or ethanol alone for 18 h, followed by stimulation with or without 0.1 ng/ml tumor necrosis factor (TNF)-α for an additional 4 h. A non-static adhesion assay was subsequently performed. Fluorescently labeled THP-1 cells were added to the HUVECs and allowed to adhere for 10 min under rotating conditions. Data are shown as means ± standard errors of the means (SEM). **p < 0.01 by a one-way analysis of variance (ANOVA) followed by Tukey’s test. (B) A monocyte adhesion assay was performed under laminar flow condition. Representative photos from three independent experiments are shown. (C) A monocyte adhesion assay was performed under laminar flow condition. Cells were perfused over activated HUVEC monolayers at a flow rate of 1.0 dyne/cm² as described in the Materials and Methods. Adherent and rolling cells were counted as described in the Materials and Methods. Data are representative of the results of three separate experiments and are shown as means ± SEM. **p < 0.01, ***p < 0.001 by one-way ANOVA followed by Tukey's test.