Figure 6.

Heparin ameliorates histone-induced endothelial inflammation. A: HPAECs were pretreated with acetylated heparin (30 or 60 U/mL) for 30 min followed by stimulation with histone H3 (20 µg/mL) alone or in combination with TNFα (0.1 ng/mL). ICAM-1 and VCAM-1 protein levels in cell lysates were determined by Western blotting. Probing for α-tubulin was used as a loading control. Bar graphs depict quantitative densitometry analysis of Western blot data; *P < 0.01 vs. H3 or TNFα alone; **P < 0.01 vs. combined treatment with H3 and TNFα; n = 3. B: sICAM-1, IL-6, and IL-8 were determined by ELISA in conditioned media from cells treated with H3 alone or combined with LPS or TNFα in the presence or absence of heparin or acetylated heparin. Data are means ± SD, n = 3, *P < 0.05 vs. LPS or TNFα alone; **P < 0.05 vs. combined agonist/H3 treatment without heparin. HPAEC, human pulmonary artery endothelial cell; LPS, lipopolysaccharide; TNF-α, tumor necrosis factor-α.